Sample records for humanized anti-her2 monoclonal

  1. Development of an Anti-HER2 Monoclonal Antibody H2Mab-139 Against Colon Cancer.

    PubMed

    Kaneko, Mika K; Yamada, Shinji; Itai, Shunsuke; Kato, Yukinari

    2018-02-01

    Human epidermal growth factor receptor 2 (HER2) expression has been reported in several cancers, such as breast, gastric, lung, pancreatic, and colorectal cancers. HER2 is overexpressed in those cancers and is associated with poor clinical outcomes. Trastuzumab, a humanized anti-HER2 antibody, provides significant survival benefits for patients with HER2-overexpressing breast cancers and gastric cancers. In this study, we developed a novel anti-HER2 monoclonal antibody (mAb), H 2 Mab-139 (IgG 1 , kappa) and investigated it against colon cancers using flow cytometry, western blot, and immunohistochemical analyses. Flow cytometry analysis revealed that H 2 Mab-139 reacted with colon cancer cell lines, such as Caco-2, HCT-116, HCT-15, HT-29, LS 174T, COLO 201, COLO 205, HCT-8, SW1116, and DLD-1. Although H 2 Mab-139 strongly reacted with LN229/HER2 cells on the western blot, we did not observe a specific signal for HER2 in colon cancer cell lines. Immunohistochemical analyses revealed sensitive and specific reactions of H 2 Mab-139 against colon cancers, indicating that H 2 Mab-139 is useful in detecting HER2 overexpression in colon cancers using flow cytometry and immunohistochemical analyses.

  2. H2Mab-77 is a Sensitive and Specific Anti-HER2 Monoclonal Antibody Against Breast Cancer.

    PubMed

    Itai, Shunsuke; Fujii, Yuki; Kaneko, Mika K; Yamada, Shinji; Nakamura, Takuro; Yanaka, Miyuki; Saidoh, Noriko; Chang, Yao-Wen; Handa, Saori; Takahashi, Maki; Suzuki, Hiroyoshi; Harada, Hiroyuki; Kato, Yukinari

    2017-08-01

    Human epidermal growth factor receptor 2 (HER2) plays a critical role in the progression of breast cancers, and HER2 overexpression is associated with poor clinical outcomes. Trastuzumab is an anti-HER2 humanized antibody that leads to significant survival benefits in patients with HER2-positive metastatic breast cancers. In this study, we developed novel anti-HER2 monoclonal antibodies (mAbs) and characterized their efficacy in flow cytometry, Western blot, and immunohistochemical analyses. Initially, we expressed the full length or ectodomain of HER2 in LN229 glioblastoma cells and then immunized mice with ectodomain of HER2 or LN229/HER2, and performed the first screening by enzyme-linked immunosorbent assays using ectodomain of HER2. Subsequently, we selected mAbs according to their efficacy in flow cytometry (second screening), Western blot (third screening), and immunohistochemical analyses (fourth screening). Among 100 mAb clones, only three mAbs reacted with HER2 in Western blot, and clone H 2 Mab-77 (IgG 1 , kappa) was selected. Finally, immunohistochemical analyses with H 2 Mab-77 showed sensitive and specific reactions against breast cancer cells, warranting the use of H 2 Mab-77 to detect HER2 in pathological analyses of breast cancers.

  3. Anti-tumor immunity induced by an anti-idiotype antibody mimicking human Her-2/neu.

    PubMed

    Mohanty, Kartik; Saha, Asim; Pal, Smarajit; Mallick, Palash; Chatterjee, Sunil K; Foon, Kenneth A; Bhattacharya-Chatterjee, Malaya

    2007-07-01

    Our goal is to apply an anti-idiotype (Id) antibody based vaccine approach for the treatment of Her-2/neu-positive human cancer. Amplification and/or over-expression of Her-2/neu occur in multiple human malignancies and are associated with poor prognosis. Her-2/neu proto-oncogene is a suitable target for cancer immunotherapy. We have developed and characterized a murine monoclonal anti-Id antibody, 6D12 that mimics a specific epitope of Her-2/neu and can be used as a surrogate antigen for Her-2/neu. In this study, the efficacy of 6D12 as a tumor vaccine was evaluated in a murine tumor model. Immunization of immunocompetent C57BL/6 mice with 6D12 conjugated to keyhole limpet hemocyanin and mixed with Freund's adjuvant or 6D12 combined with the adjuvant QS21 induced anti-6D12 as well as anti-Her-2/neu immunity. Her-2/neu-positive human breast carcinoma cells, SK-BR-3 reacted with immunized mice sera as determined by ELISA and flow cytometry. Flow cytometry analysis also demonstrated strong reactivity of immunized mice sera with human Her-2/neu transfected EL4 cells (EL4-Her-2), but no reactivity with nontransfected parental EL4 cells. Antibody dependent cellular cytotoxicity against EL4-Her-2 cells was also observed in presence of immune sera. Mice immunized with 6D12 were protected against a challenge with lethal doses of EL4-Her-2 cells, whereas no protection was observed against parental EL4 cells or when mice were immunized with an unrelated anti-Id antibody and challenged with EL4-Her-2 cells. These data suggest that anti-Id 6D12 vaccine can induce protective Her-2/neu specific antitumor immunity and may serve as a potential network antigen for the treatment of patients with Her-2/neu-positive tumors.

  4. Overview of the trastuzumab (Herceptin) anti-HER2 monoclonal antibody clinical program in HER2-overexpressing metastatic breast cancer. Herceptin Multinational Investigator Study Group.

    PubMed

    Shak, S

    1999-08-01

    The recombinant humanized anti-HER2 monoclonal antibody trastuzumab (Herceptin; Genentech, San Francisco, CA) was evaluated in human clinical trials for treatment of women with metastatic breast cancer who have tumors that overexpress HER2. The trastuzumab clinical program consisted of a series of phase I, phase II, and phase III clinical trials. Clinical experience with this novel biologic has been obtained in more than 1,000 women with HER2-overexpressing metastatic breast cancer. Two pivotal trials were performed to evaluate trastuzumab efficacy and safety: (1) trastuzumab in combination with chemotherapy as first-line therapy and (2) trastuzumab as a single agent in second- and third-line chemotherapy. Preliminary results of the pivotal clinical trials that have been presented at national meetings are summarized below. The data suggest that trastuzumab will be an important new treatment option for women with HER2-overexpressing metastatic breast cancer.

  5. Establishment of H2Mab-119, an Anti-Human Epidermal Growth Factor Receptor 2 Monoclonal Antibody, Against Pancreatic Cancer.

    PubMed

    Yamada, Shinji; Itai, Shunsuke; Nakamura, Takuro; Chang, Yao-Wen; Harada, Hiroyuki; Suzuki, Hiroyoshi; Kaneko, Mika K; Kato, Yukinari

    2017-12-01

    Human epidermal growth factor receptor 2 (HER2) is overexpressed in breast cancer and is associated with poor clinical outcomes. In addition, HER2 expression has been reported in other cancers, such as gastric, colorectal, lung, and pancreatic cancers. An anti-HER2 humanized antibody, trastuzumab, leads to significant survival benefits in patients with HER2-overexpressing breast cancers and gastric cancers. Herein, we established a novel anti-HER2 monoclonal antibody (mAb), H 2 Mab-119 (IgG 1 , kappa), and characterized its efficacy against pancreatic cancers using flow cytometry, Western blot, and immunohistochemical analyses. H 2 Mab-119 reacted with pancreatic cancer cell lines, such as KLM-1, Capan-2, and MIA PaCa-2, but did not react with PANC-1 in flow cytometry analysis. Western blot analysis also revealed a moderate signal for KLM-1 and a weak signal for MIA PaCa-2, although H 2 Mab-119 reacted strongly with LN229/HER2 cells. Finally, immunohistochemical analyses with H 2 Mab-119 revealed sensitive and specific reactions against breast and colon cancers but did not react with pancreatic cancers, indicating that H 2 Mab-119 is useful for detecting HER2 overexpression in pancreatic cancers using flow cytometry and Western blot analyses.

  6. A single-domain antibody-linked Fab bispecific antibody Her2-S-Fab has potent cytotoxicity against Her2-expressing tumor cells.

    PubMed

    Li, Aifen; Xing, Jieyu; Li, Li; Zhou, Changhua; Dong, Bin; He, Ping; Li, Qing; Wang, Zhong

    2016-12-01

    Her2, which is frequently overexpressed in breast cancer, is one of the most studied tumor-associated antigens for cancer therapy. Anti-HER2 monoclonal antibody, trastuzumab, has achieved significant clinical benefits in metastatic breast cancer. In this study, we describe a novel bispecific antibody Her2-S-Fab targeting Her2 by linking a single domain anti-CD16 VHH to the trastuzumab Fab. The Her2-S-Fab antibody can be efficiently expressed and purified from Escherichia coli, and drive potent cancer cell killing in HER2-overexpressing cancer cells. In xenograft model, the Her2-S-Fab suppresses tumor growth in the presence of human immune cells. Our results suggest that the bispecific Her2-S-Fab may provide a valid alternative to Her2 positive cancer therapy.

  7. Targeting multiple Her-2 epitopes with monoclonal antibodies results in improved antigrowth activity of a human breast cancer cell line in vitro and in vivo.

    PubMed

    Spiridon, Camelia I; Ghetie, Maria-Ana; Uhr, Jonathan; Marches, Radu; Li, Jia-Ling; Shen, Guo-Liang; Vitetta, Ellen S

    2002-06-01

    Her-2 (p185(erbB-2)) is a transmembrane tyrosine kinase receptor, which is encoded by the Her-2/neu proto-oncogene. Her-2 is overexpressed on 30% of highly malignant breast cancers. Monoclonal antibodies (MAbs) against Her-2 inhibit the growth of Her-2-overexpressing tumor cells and this occurs by a variety of mechanisms. One such MAb, Herceptin (Trastuzumab), has been approved for human use. We have generated a panel of murine anti-Her-2 MAbs against nine different epitopes on the extracellular domain of Her-2 and have evaluated the antitumor activity of three of these MAbs alone and in combination, both in vitro and in vivo. We found that MAbs (against different epitopes) make a highly effective mixture, which was more effective than the individual MAbs in treating s.c. tumor nodules of BT474 cells in SCID mice. In vitro, the MAb mixture was also more effective than the single MAbs in inducing antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity, inhibiting cell growth and inducing apoptosis, and inhibiting the secretion of vascular endothelial growth factor. Taken together, these activities might explain the superior performance of the MAb mixture in vivo.

  8. The anti-HER3 antibody in combination with trastuzumab exerts synergistic antitumor activity in HER2-positive gastric cancer.

    PubMed

    Wang, Qiwei; Zhang, Xiaotian; Shen, Enyun; Gao, Jing; Cao, Fengqi; Wang, Xiaojuan; Li, Yilin; Tian, Tiantian; Wang, Jingyuan; Chen, Zuhua; Wang, Jiayuan; Shen, Lin

    2016-09-28

    The anti-HER2 monoclonal antibody trastuzumab is central to the treatment of HER2-positive gastric cancer (GC); however, its responses are limited. HER3 seems to be the preferred dimerization partner with HER2 and is emerging as a key target for complete blockade of downstream pathways and better clinical response. In this study, we report that novel anti-HER3 antibodies (1A5-3D4) that can neutralize multiple modes of HER3 activation, combined with trastuzumab, exhibited synergistic inhibitory effect on the cell proliferation in HER2-positive GC cell lines. Follow-up studies revealed that the combination treatment significantly inhibited phosphorylation of HER3 as well as AKT and ERK signals. In vivo experiments further showed that the anti-tumor effect of trastuzumab was enhanced by its combination with 1A5-3D4 in NCI-N87 xenograft and patient derived xenografts (PDX). Particularly in an HER2-negative whereas neuregulin1 (a ligand of HER3) positive PDX, the combination was also superior to monotherapy. 1A5-3D4 in combination with trastuzumab exhibits a synergistic inhibitory effect on tumor activity, suggesting that targeting both HER2 and HER3 resulted in an improved treatment effects on HER2-positive GC. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. PE38KDEL-loaded anti-HER2 nanoparticles inhibit breast tumor progression with reduced toxicity and immunogenicity.

    PubMed

    Gao, Jie; Kou, Geng; Wang, Hao; Chen, Huaiwen; Li, Bohua; Lu, Ying; Zhang, Dapeng; Wang, Shuhui; Hou, Sheng; Qian, Weizhu; Dai, Jianxin; Zhao, Jian; Zhong, Yanqiang; Guo, Yajun

    2009-05-01

    The clinical use of Pseudomonas exotoxin A (PE)-based immunotoxins is limited by the toxicity and immunogenicity of PE. To overcome the limitations, we have developed PE38KDEL-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles conjugated with Fab' fragments of a humanized anti-HER2 monoclonal antibody (rhuMAbHER2). The PE38KDEL-loaded nanoparticles-anti-HER2 Fab' bioconjugates (PE-NP-HER) were constructed modularly with Fab' fragments of rhuMAbHER2 covalently linked to PLGA nanoparticles containing PE38KDEL. Compared with nontargeted nanoparticles that lack anti-HER2 Fab', PE-NP-HER specifically bound to and were sequentially internalized into HER2 overexpressing breast cancer cells, which result in significant cytotoxicity in vitro. In HER2 overexpressing tumor xenograft model system, administration of PE-NP-HER showed a superior efficacy in inhibiting tumor growth compared with PE-HER referring to PE38KDEL conjugated directly to rhuMAbHER2. Moreover, PE-NP-HER was well tolerated in mice with a higher LD(50) (LD(50) of 6.86 +/- 0.47 mg/kg vs. 2.21 +/- 0.32 mg/kg for PE-NP-HER vs. PE-HER (mean +/- SD); n = 3), and had no influence on the plasma level of plasma alanine aminotransferase (ALT) of animals when injected at a dose of 1 mg/kg where PE-HER caused significant increase of serum ALT in the treated mice. Notably, PE-NP-HER was of low immunogenicity in development of anti-PE38KDEL neutralizing antibodies and was less susceptible to inactivation by anti-PE38KDEL antibodies compared with PE-HER. This novel bioconjugate, PE-NP-HER, may represent a useful strategy for cancer treatment.

  10. Gallium-68-labeled anti-HER2 single-chain Fv fragment: development and in vivo monitoring of HER2 expression.

    PubMed

    Ueda, Masashi; Hisada, Hayato; Temma, Takashi; Shimizu, Yoichi; Kimura, Hiroyuki; Ono, Masahiro; Nakamoto, Yuji; Togashi, Kaori; Saji, Hideo

    2015-02-01

    We aimed to develop a gallium-68 (Ga-68)-labeled single-chain variable fragment (scFv) targeting the human epidermal growth factor receptor 2 (HER2) to rapidly and noninvasively evaluate the status of HER2 expression. Anti-HER2 scFv was labeled with Ga-68 by using deferoxamine (Df) as a bifunctional chelate. Biodistribution of [(68)Ga]Df-anti-HER2 scFv was examined with tumor-bearing mice and positron emission tomography (PET) imaging was performed. The changes in HER2 expression after anti-HER2 therapy were monitored by PET imaging. [(68)Ga]Df-anti-HER2 scFv was obtained with high radiochemical yield after only a 5-min reaction at room temperature. The probe showed high accumulation in HER2-positive xenografts and the intratumoral distribution of radioactivity coincided with HER2-positive regions. Furthermore, [(68)Ga]Df-anti-HER2 scFv helped visualize HER2-positive xenografts and monitor the changes in HER2 expression after anti-HER2 therapy. [(68)Ga]Df-anti-HER2 scFv could be a promising probe to evaluate HER2 status by in vivo PET imaging, unless trastuzumab is prescribed as part of the therapy.

  11. Preparation and biological activities of anti-HER2 monoclonal antibodies with fully core-fucosylated homogeneous bi-antennary complex-type glycans.

    PubMed

    Tsukimura, Wataru; Kurogochi, Masaki; Mori, Masako; Osumi, Kenji; Matsuda, Akio; Takegawa, Kaoru; Furukawa, Kiyoshi; Shirai, Takashi

    2017-12-01

    Recently, the absence of a core-fucose residue in the N-glycan has been implicated to be important for enhancing antibody-dependent cellular cytotoxicity (ADCC) activity of immunoglobulin G monoclonal antibodies (mAbs). Here, we first prepared anti-HER2 mAbs having two core-fucosylated N-glycan chains with the single G2F, G1aF, G1bF, or G0F structure, together with those having two N-glycan chains with a single non-core-fucosylated corresponding structure for comparison, and determined their biological activities. Dissociation constants of mAbs with core-fucosylated N-glycans bound to recombinant Fcγ-receptor type IIIa variant were 10 times higher than those with the non-core-fucosylated N-glycans, regardless of core glycan structures. mAbs with the core-fucosylated N-glycans had markedly reduced ADCC activities, while those with the non-core-fucosylated N-glycans had high activities. These results indicate that the presence of a core-fucose residue in the N-glycan suppresses the binding to the Fc-receptor and the induction of ADCC of anti-HER2 mAbs.

  12. [Targeted detecting HER2 expression with recombinant anti HER2 ScFv-GFP fusion antibody].

    PubMed

    Gao, Guohui; Chen, Chong; Yang, Yanmei; Yang, Han; Wang, Jindan; Zheng, Yi; Huang, Qidi; Hu, Xiaoqu

    2012-08-01

    To verify the reliability of targeted detecting HER2 positive cancer cells and clinical pathological tissue specimens with a recombinant anti HER2 single chain antibody in single chain Fv fragment (scFv) format, we have constructed the fusion variable regions of the ScFv specific for HER2/neu. labeled a green-fluorescent protein(GFP). The humanized recombinant Anti HER2 ScFv-GFP gene was inserted into pFast Bac HT A, and expressed in insect cells sf9. Then the recombinant fusion protein Anti HER2 ScFv-GFP was properly purified with Ni2+-NTA affinity chromatography from the infected sf9 cells used to test the specificity of the fusion antibody for HER2 positive cancer cells. Firstly, the purified antibody incubated with HER2 positive breast cancer cells SKBR3, BT474 and HER2 negative breast cancer cells MCF7 for 12 h/24 h/48 h at 37 degrees C, in order to confirm targeted detecting HER2 positive breast cancer cells by Laser Confocal Microscopy. Furthermore, the same clinical pathological tissue samples were assessed by immunohistochemistry (IHC) and the fusion antibody Anti HER2 ScFv-GFP in the meanwhile. The data obtained indicated that the recombinant eukaryotic expression plasmid pFast Bac HT A/Anti HER2 ScFv-GFP was constructed successfully In addition, obvious green fluorescent was observed in insect cells sf9. When the purified fusion antibody was incubated with different cancer cells, much more green fluorescent was observed on the surface of the HER2 positive cancer cells SKBR3 and BT474. In contrast, no green fluorescent on the surface of the HER2 negative cancer cells MCF7 was detected. The concentration of the purified fusion antibody was 115.5 microg/mL, of which protein relative molecular weight was 60 kDa. The analysis showed the purity was about 97% and the titer was about 1:64. The detection results of IHC and fusion antibody testing indicated the conformity. In summary, the study showed that the new fusion antibody Anti HER2 ScFv-GFP can test HER2

  13. EGFR, HER2 and VEGF pathways: validated targets for cancer treatment.

    PubMed

    Press, Michael F; Lenz, Heinz-Josef

    2007-01-01

    Targeted therapies are rationally designed to interfere with specific molecular events that are important in tumour growth, progression or survival. Several targeted therapies with anti-tumour activity in human cancer cell lines and xenograft models have now been shown to produce objective responses, delay disease progression and, in some cases, improve survival of patients with advanced malignancies. These targeted therapies include cetuximab, an anti-epidermal growth factor receptor (EGFR) monoclonal antibody; gefitinib and erlotinib, EGFR-specific tyrosine kinase inhibitors; trastuzumab, an anti-human EGFR type 2 (HER2)-related monoclonal antibody; lapatinib, a dual inhibitor of both EGFR- and HER2-associated tyrosine kinases; and bevacizumab, an anti-vascular endothelial growth factor (VEGF) monoclonal antibody. On the basis of preclinical and clinical evidence, EGFR, HER2 and VEGF represent validated targets for cancer therapy and remain the subject of intensive investigation. Both EGFR and HER2 are targets found on cancer cells, whereas VEGF is a target that acts in the tumour microenvironment. Clinical studies are focusing on how to best incorporate targeted therapy into current treatment regimens and other studies are exploring whether different strategies for inhibiting these targets will offer greater benefit. It is clear that optimal use of targeted therapy will depend on understanding how these drugs work mechanistically, and recognising that their activities may differ across patient populations, tumour types and disease stages, as well as when and how they are used in cancer treatment. The results achieved with targeted therapies to date are promising, although they illustrate the need for additional preclinical and clinical study.

  14. HER2 specific delivery of methotrexate by dendrimer conjugated anti-HER2 mAb

    NASA Astrophysics Data System (ADS)

    Shukla, Rameshwer; Thomas, Thommey P.; Desai, Ankur M.; Kotlyar, Alina; Park, Steve J.; Baker, James R., Jr.

    2008-07-01

    Herceptin, a humanized monoclonal antibody that binds to human growth factor receptor-2 (HER2), was covalently attached to a fifth-generation (G5) polyamidoamine dendrimer containing the cytotoxic drug methotrexate. The specific binding and internalization of this conjugate labeled with FITC was clearly demonstrated in cell lines overexpressing HER2 by flow cytometry as well as confocal microscopic analysis. In addition, binding and uptake of antibody conjugated dendrimers was completely blocked by excess non-conjugated herceptin. The dendrimer conjugate was also shown to inhibit the dihydrofolate reductase with similar activity to methotrexate. Co-localization experiments with lysotracker red indicate that antibody conjugate, although internalized efficiently into cells, has an unusually long residence time in the lysosome. Somewhat lower cytotoxicity of the conjugate in comparison to free methotrexate was attributed to the slow release of methotrexate from the conjugate and its long retention in the lysosomal pocket.

  15. Generation of HER2 monoclonal antibodies using epitopes of a rabbit polyclonal antibody.

    PubMed

    Hu, Francis Jingxin; Uhlen, Mathias; Rockberg, Johan

    2014-01-25

    One of the issues in using polyclonal antibodies is the limited amount of reagent available from an immunisation, leading to batch-to-batch variation and difficulties in obtaining the same antibody performance when the same antigen is re-immunised into several separate animals. This led to the development of hybridoma technology allowing, at least theoretically, for an unlimited production of a specific binder. Nevertheless, polyclonal antibodies are widely used in research and diagnostics and there exists a need for robust methods to convert a polyclonal antibody with good binding performance into a renewable monoclonal with identical or similar binding specificity. Here we have used precise information regarding the functional recognition sequence (epitope) of a rabbit polyclonal antibody with attractive binding characteristics as the basis for generation of a renewable mouse monoclonal antibody. First, the original protein fragment antigen was used for immunisation and generation of mouse hybridoma, without obtaining binders to the same epitope region. Instead a peptide designed using the functional epitope and structural information was synthesised and used for hybridoma production. Several of the monoclonal antibodies generated were found to have similar binding characteristics to those of the original polyclonal antibody. These monoclonal antibodies detected native HER2 on cell lines and were also able to stain HER2 in immunohistochemistry using xenografted mice, as well as human normal and cancer tissues. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. DaMab-2: Anti-Human DGKα Monoclonal Antibody for Immunocytochemistry.

    PubMed

    Nakano, Tomoyuki; Ogasawara, Satoshi; Tanaka, Toshiaki; Hozumi, Yasukazu; Mizuno, Satoru; Satoh, Eri; Sakane, Fumio; Okada, Naoki; Taketomi, Akinobu; Honma, Ryusuke; Nakamura, Takuro; Saidoh, Noriko; Yanaka, Miyuki; Itai, Shunsuke; Handa, Saori; Chang, Yao-Wen; Yamada, Shinji; Kaneko, Mika K; Kato, Yukinari; Goto, Kaoru

    2017-08-01

    Diacylglycerol kinase (DGK) is responsible for the enzymatic conversion of diacylglycerol to phosphatidic acid. Since both diacylglycerol and phosphatidic acid serve as signaling molecules, DGK is regarded as a hub between diacylglycerol-mediated and phosphatidic acid-mediated signaling. One of the 10 DGK isozymes, DGKα, is shown to be involved in T cell function. Transfection studies using tagged expression vectors revealed that DGKα localizes to the cytoplasm and nucleus and translocates to the plasma membrane in response to T cell receptor stimulation. However, a limited number of studies reported the localization of native protein of DGKα in tissues and cells. In this study, we immunized mice with recombinant DGKα and developed several anti-DGKα monoclonal antibodies (mAbs). One of the established anti-DGKα mAbs is a clone DaMab-2 (mouse IgG 1 , kappa). In enzyme-linked immunosorbent assay, DaMab-2 recognized only DGKα, and did not react with the other isozymes, such as DGKγ, DGKζ, DGKη, and DGKδ. Importantly, DaMab-2 is very useful in immunocytochemical analysis of human cultured cells, indicating that DaMab-2 is advantageous to analyze the localization and function of DGKα.

  17. Neural Stem Cells Secreting Anti-HER2 Antibody Improve Survival in a Preclinical Model of HER2 Overexpressing Breast Cancer Brain Metastases.

    PubMed

    Kanojia, Deepak; Balyasnikova, Irina V; Morshed, Ramin A; Frank, Richard T; Yu, Dou; Zhang, Lingjiao; Spencer, Drew A; Kim, Julius W; Han, Yu; Yu, Dihua; Ahmed, Atique U; Aboody, Karen S; Lesniak, Maciej S

    2015-10-01

    The treatment of human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer has been revolutionized by trastuzumab. However, longer survival of these patients now predisposes them to forming HER2 positive brain metastases, as the therapeutic antibodies cannot cross the blood brain barrier. The current oncologic repertoire does not offer a rational, nontoxic targeted therapy for brain metastases. In this study, we used an established human neural stem cell line, HB1.F3 NSCs and generated a stable pool of cells secreting a high amount of functional full-length anti-HER2 antibody, equivalent to trastuzumab. Anti-HER2Ab secreted by the NSCs (HER2Ab-NSCs) specifically binds to HER2 overexpressing human breast cancer cells and inhibits PI3K-Akt signaling. This translates to HER2Ab-NSC inhibition of breast cancer cell growth in vitro. Preclinical in vivo experiments using HER2Ab overexpressing NSCs in a breast cancer brain metastases (BCBM) mouse model demonstrate that intracranial injection of HER2Ab-NSCs significantly improves survival. In effect, these NSCs provide tumor localized production of HER2Ab, minimizing any potential off-target side effects. Our results establish HER2Ab-NSCs as a novel, nontoxic, and rational therapeutic approach for the successful treatment of HER2 overexpressing BCBM, which now warrants further preclinical and clinical investigation. © 2015 AlphaMed Press.

  18. Brain metastases in Asian HER2-positive breast cancer patients: anti-HER2 treatments and their impact on survival.

    PubMed

    Yap, Y S; Cornelio, G H; Devi, B C R; Khorprasert, C; Kim, S B; Kim, T Y; Lee, S C; Park, Y H; Sohn, J H; Sutandyo, N; Wong, D W Y; Kobayashi, M; Landis, S H; Yeoh, E M; Moon, H; Ro, J

    2012-09-25

    In Asia, large-scale studies on anti-HER2 treatment in HER2-positive breast cancer patients with brain metastases are limited. We studied the treatment patterns of these patients in Asia to evaluate the impact of anti-HER2 treatment on the time to occurrence of brain metastases (TTBM) and survival after brain metastasis (BM). A retrospective study of HER2-positive breast cancer patients diagnosed with BM between January 2006 and December 2008 in six Asian countries was conducted. Demographics, tumour characteristics, treatment details, and events dates were collected from medical records. Data from 280 patients were analysed. Before BM, 63% received anti-HER2 treatment. These patients had significantly longer TTBM than those without anti-HER2 treatment (median 33 vs 19 months; P<0.002). After BM, 93% received radiotherapy, 57% received chemotherapy, and 41% received anti-HER2 treatment (trastuzumab and/or lapatinib). Use of both anti-HER2 agents, primarily sequentially, after BM demonstrated the longest survival after BM and was associated with a significant survival benefit over no anti-HER2 treatment (median 26 vs 6 months; hazard ratio 0.37; 95% CI 0.19-0.72). Anti-HER2 treatment before BM was associated with longer TTBM. Anti-HER2 treatment after BM was associated with a survival benefit, especially when both trastuzumab and lapatinib were utilised.

  19. Multiepitope HER2 targeting enhances photoimmunotherapy of HER2-overexpressing cancer cells with pyropheophorbide-a immunoconjugates.

    PubMed

    Savellano, Mark D; Pogue, Brian W; Hoopes, P Jack; Vitetta, Ellen S; Paulsen, Keith D

    2005-07-15

    Multi-targeting strategies improve the efficacy of antibody and immunotoxin therapies but have not yet been thoroughly explored for HER2-based cancer treatments. We investigated multi-epitope HER2 targeting to boost photosensitizer immunoconjugate uptake as a way of enhancing photoimmunotherapy. Photoimmunotherapy may allow targeted photodynamic destruction of malignancies and may also potentiate anticancer antibodies. However, one obstacle preventing its clinical use is the delivery of enough photosensitizer immunoconjugates to target cells. Anti-HER2 photosensitizer immunoconjugates were constructed from two monoclonal antibodies (mAb), HER50 and HER66, using a novel method originally developed to label photosensitizer immunoconjugates with the photosensitizer, benzoporphyrin derivative verteporfin. Photosensitizer immunoconjugates were labeled instead with a promising alternative photosensitizer, pyropheophorbide-a (PPa), which required only minor changes to the conjugation procedure. Uptake and phototoxicity experiments using human cancer cells were conducted with the photosensitizer immunoconjugates and, for comparison, with free PPa. SK-BR-3 and SK-OV-3 cells served as HER2-overexpressing target cells. MDA-MB-468 cells served as HER2-nonexpressing control cells. Photosensitizer immunoconjugates with PPa/mAb molar ratios up to approximately 10 specifically targeted and photodynamically killed HER2-overexpressing cells. On a per mole basis, photosensitizer immunoconjugates were less phototoxic than free PPa, but photosensitizer immunoconjugates were selective for target cells whereas free PPa was not. Multiepitope targeted photoimmunotherapy with a HER50 and HER66 photosensitizer immunoconjugate mixture was significantly more effective than single-epitope targeted photoimmunotherapy with a single anti-HER2 photosensitizer immunoconjugate, provided photosensitizer immunoconjugate binding was saturated. This study shows that multiepitope targeting enhances HER2

  20. Anti-HER2 Therapy Beyond Second-Line for HER2-Positive Metastatic Breast Cancer: A Short Review and Recommendations for Several Clinical Scenarios from a Spanish Expert Panel

    PubMed Central

    Martínez-Jañez, Noelia; Chacón, Ignacio; de Juan, Ana; Cruz-Merino, Luis; del Barco, Sònia; Fernández, Isaura; García-Teijido, Paula; Gómez-Bernal, Amalia; Plazaola, Arrate; Ponce, José; Servitja, Sonia; Zamora, Pilar

    2016-01-01

    Summary Background The aim of this project was to provide an expert opinion regarding anti-human epidermal growth factor receptor 2 (HER2) therapy beyond second-line treatment of metastatic breast cancer (mBC). Methods A group of experts discussed specific issues concerning anti-HER2 therapy in late-line settings in mBC. Results Trastuzumab emtansine (T-DM1) or dual HER2 blockade appeared to be good options for HER2-positive mBC after ≥ 2 HER2-targeted therapies. Once an objective response has been achieved with anti-HER2-containing therapy, the anti-HER2 agent can be continued until progression of the disease, unacceptable toxicity or patient decision. mBC treated with ≥ 3 consecutive lines of anti-HER therapy, ≥ 1 being a dual HER2 blockade and with early progression of disease during a fourth or later-line treatment, are clinically resistant to anti-HER therapy. For progression of metastasis in the brain after anti-HER2 therapy, lapatinib and chemotherapy appear to be a good alternative after best local treatment. Conclusions Further clinical trials are needed to provide valuable knowledge about the best treatment options in the later settings of mBC. PMID:27239176

  1. Survival benefit of anti-HER2 therapy after whole-brain radiotherapy in HER2-positive breast cancer patients with brain metastasis.

    PubMed

    Zhang, Qian; Chen, Jian; Yu, Xiaoli; Cai, Gang; Yang, Zhaozhi; Cao, Lu; Hu, Chaosu; Guo, Xiaomao; Sun, Jing; Chen, Jiayi

    2016-09-01

    We aimed to assess the survival benefit of epidermal growth factor receptor 2 (HER2)-positive breast cancer patients with brain metastasis (BM) after whole-brain radiotherapy (WBRT) in combination with systemic treatments, especially anti-HER2 therapy. This retrospective study analyzed the overall survival (OS) of 60 HER2-positive breast cancer patients with BM after WBRT in combination with systemic treatments. Among them, 42 patients received chemotherapy while 18 patients did not receive after WBRT. With regard to anti-HER2 therapy, after WBRT, 17 patients received anti-HER2 treatment without prior adjuvant trastuzumab-based therapy, 7 patients received anti-HER2 treatment with prior adjuvant trastuzumab-based therapy, and 36 patients did not receive further anti-HER2 treatment. All patients were followed up regularly until January 23, 2013. The median OS of patients with BM was 12 months. Patients who received anti-HER2 therapy and chemotherapy after WBRT had significantly better survival compared with patients who did not receive further treatment. Patients who received anti-HER2 treatment after WBRT but did not receive adjuvant trastuzumab-based therapy for early breast cancer had better OS, followed by patients who received anti-HER2 agent both in adjuvant treatment and after WBRT and patients who did not receive anti-HER2 treatment. Multivariate analysis showed that Karnofsky Performance Status, control of extracranial metastases, chemotherapy after WBRT, and anti-HER2 therapy combined with WBRT were all independent predictors for OS. Both chemotherapy and anti-HER2 therapy after WBRT could improve OS. Moreover, patients without prior exposure to adjuvant anti-HER2 treatment may have survival benefit superior to those of patients with prior exposure.

  2. Comparison of humanized IgG and FvFc anti-CD3 monoclonal antibodies expressed in CHO cells.

    PubMed

    Serpieri, Flavia; Inocencio, Andre; de Oliveira, Jose Marcelino; Pimenta, Alécio A; Garbuio, Angélica; Kalil, Jorge; Brigido, Marcelo M; Moro, Ana Maria

    2010-07-01

    Two humanized monoclonal antibody constructs bearing the same variable regions of an anti-CD3 monoclonal antibody, whole IgG and FvFc, were expressed in CHO cells. Random and site-specific integration were used resulting in similar expression levels. The transfectants were selected with appropriate selection agent, and the surviving cells were plated in semi-solid medium for capture with FITC-conjugated anti-human IG antibody and picked with the robotic ClonePix FL. Conditioned media from selected clones were purified by affinity chromatography and characterized by SDS-PAGE, Western-blot, SEC-HPLC, and isoelectric focusing. Binding to the target present in healthy human mononuclear cells was assessed by flow cytometry, as well as by competition between the two constructs and the original murine monoclonal antibody. The humanized constructs were not able to dislodge the murine antibody while the murine anti-CD3 antibody could dislodge around 20% of the FvFc or IgG humanized versions. Further in vitro and in vivo pre-clinical analyses will be carried out to verify the ability of the humanized versions to demonstrate the immunoregulatory profile required for a humanized anti-CD3 monoclonal antibody.

  3. ICG-loaded polymeric nanocapsules functionalized with anti-HER2 for targeted fluorescence imaging and photodestruction of ovarian cancer cells

    NASA Astrophysics Data System (ADS)

    Bahmani, Baharak; Guerrero, Yadir; Vullev, Valentine; Singh, Sheela P.; Kundra, Vikas; Anvari, Bahman

    2013-03-01

    Optical nano-materials present a promising platform for targeted molecular imaging of cancer biomarkers and its photodestruction. Our group is investigating the use of polymeric nanoparticles, loaded with indocyanine green, an FDA-approved chromophore, as a theranostic agent for targeted intraoperative optical imaging and laser-mediated destruction of ovarian cancer. These ICG-loaded nanocapsules (ICG-NCs) can be functionalized by covalent attachment of targeting moieties onto their surface. Here, we investigate ICG-NCs functionalized with anti-HER2 for targeted fluorescence imaging and laser-mediated destruction of ovarian cancer cells in vitro. ICG-NCs are formed through ionic cross-linking between polyallylamine hydrochloride chains and sodium phosphate ions followed by diffusion-mediated loading with ICG. Before functionalization with antibodies, the surface of ICG-NCs is coated with single and double aldehyde terminated polyethylene glycol (PEG). The monoclonal anti-HER2 is covalently coupled to the PEGylated ICG-NCs using reductive amination to target the HER2 receptor, a biomarker whose over-expression is associated with increased risk of cancer progression. We quantify uptake of anti-HER2 conjugated ICG-NCs by ovarian cancer cells using flow cytometery. The in-vitro laser-mediated destruction of SKOV3 cells incubated with anti-HER2 functionalized ICG-NCs is performed using an 808 nm diode laser. Cell viability is characterized using the Calcein and Ethidium homodimer-1 assays following laser irradiation. Our results indicate that anti-HER2 functionalized ICG-NCs can be used as theranostic agents for optical molecular imaging and photodestruction of ovarian cancers in-vitro.

  4. Immunization with a novel chimeric peptide representing B and T cell epitopes from HER2 extracellular domain (HER2 ECD) for breast cancer.

    PubMed

    Mahdavi, Manijeh; Keyhanfar, Mehrnaz; Jafarian, Abbas; Mohabatkar, Hassan; Rabbani, Mohammad

    2014-12-01

    Because of direct stimulating immune system against disease, vaccination or active immunotherapy is preferable compared to passive immunotherapy. For this purpose, a newly designed chimeric peptide containing epitopes for both B and T cells from HER2 ECD subdomain III was proposed. To evaluate the effects of the active immunization, a discontinuous B cell epitope peptide was selected based on average antigenicity by bioinformatics analysis. The selected peptide was collinearly synthesized as a chimera with a T helper epitope from the protein sequence of measles virus fusion (208-302) using the GPSL linker. Three mice were immunized with the chimeric peptide. Reactive antibodies with HER2 protein in ELISA and immunofluorescence assays with no cross-reactivity were generated. The 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay indicated that the anti-peptide sera had inhibitory effects on proliferation of SK-BR-3 cells. Hence, the newly designed, discontinuous chimeric peptide representing B and T cell epitopes from subdomain III of HER2-ECD can form the basis for future vaccines design, where these data can be applied for monoclonal antibody production targeting the distinct epitope of HER2 receptor compared to the two broadly used anti-HER2 monoclonal antibodies, Herceptin and pertuzumab.

  5. Anti-HER2 CD4(+) T-helper type 1 response is a novel immune correlate to pathologic response following neoadjuvant therapy in HER2-positive breast cancer.

    PubMed

    Datta, Jashodeep; Berk, Erik; Xu, Shuwen; Fitzpatrick, Elizabeth; Rosemblit, Cinthia; Lowenfeld, Lea; Goodman, Noah; Lewis, David A; Zhang, Paul J; Fisher, Carla; Roses, Robert E; DeMichele, Angela; Czerniecki, Brian J

    2015-05-23

    A progressive loss of circulating anti-human epidermal growth factor receptor-2/neu (HER2) CD4(+) T-helper type 1 (Th1) immune responses is observed in HER2(pos)-invasive breast cancer (IBC) patients relative to healthy controls. Pathologic complete response (pCR) following neoadjuvant trastuzumab and chemotherapy (T + C) is associated with decreased recurrence and improved prognosis. We examined differences in anti-HER2 Th1 responses between pCR and non-pCR patients to identify modifiable immune correlates to pathologic response following neoadjuvant T + C. Anti-HER2 Th1 responses in 87 HER2(pos)-IBC patients were examined using peripheral blood mononuclear cells pulsed with 6 HER2-derived class II peptides via IFN-γ ELISPOT. Th1 response metrics were anti-HER2 responsivity, repertoire (number of reactive peptides), and cumulative response across 6 peptides (spot-forming cells [SFC]/10(6) cells). Anti-HER2 Th1 responses of non-pCR patients (n = 4) receiving adjuvant HER2-pulsed type 1-polarized dendritic cell (DC1) vaccination were analyzed pre- and post-immunization. Depressed anti-HER2 Th1 responses observed in treatment-naïve HER2(pos)-IBC patients (n = 22) did not improve globally in T + C-treated HER2(pos)-IBC patients (n = 65). Compared with adjuvant T + C receipt, neoadjuvant T + C - utilized in 61.5 % - was associated with higher anti-HER2 Th1 repertoire (p = 0.048). While pCR (n = 16) and non-pCR (n = 24) patients did not differ substantially in demographic/clinical characteristics, pCR patients demonstrated dramatically higher anti-HER2 Th1 responsivity (94 % vs. 33 %, p = 0.0002), repertoire (3.3 vs. 0.3 peptides, p < 0.0001), and cumulative response (148.2 vs. 22.4 SFC/10(6), p < 0.0001) versus non-pCR patients. After controlling for potential confounders, anti-HER2 Th1 responsivity remained independently associated with pathologic response (odds ratio 8.82, p = 0.016). This IFN-γ(+) immune disparity was mediated by anti-HER2 CD4(+)T

  6. Development of a highly specific HER2 monoclonal antibody for immunohistochemistry using protein microarray chips

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Qi, Lili; Zhou, Lixin; Lu, Mingmin

    HER2 is an orphan receptor tyrosine kinase of the EGFR families and is considered to be a key tumor driver gene [1]. Breast cancer and gastric cancer with HER2 amplification can be effectively treated by its neutralizing antibody, Herceptin. In clinic, Immunohistochemistry (IHC) was used as the primary screening method to diagnose HER2 amplification [2]. However, recent evidence suggested that the frequently used rabbit HER2 antibody 4B5 cross reacted with another family member HER4 [3]. IHC staining with 4B5 also indicated that there was strong non-specific cytoplasmic and nuclear signals in normal gastric mucosal cells and some gastric cancer samples.more » Using a protein lysate array which covers 85% of the human proteome, we have confirmed that the 4B5 bound to HER4 and a nuclear protein ZSCAN18 besides HER2. The non-specific binding accounts for the unexpected cytoplasmic and nuclear staining of 4B5 of normal gastric epithelium. Finally, we have developed a novel mouse HER2 monoclonal antibody UMAB36 with similar sensitivity to 4B5 but only reacted to HER2 across the 17,000 proteins on the protein chip. In 129 breast cancer and 158 gastric cancer samples, UMAB36 showed 100% sensitivity and specificity comparing to the HER2 FISH reference results with no unspecific staining in the gastric mucosa layer. Therefore, UMAB36 could provide as an alternative highly specific IHC reagent for testing HER2 amplification in gastric cancer populations. - Highlights: • HER2 antibody 4B5 cross-interacts with HER4 and ZSCAN18, which would interfere with the accuracy of IHC diagnosis of HER2. • A HER2 antibody UMAB36 has been developed with high sensitivity and specificity and can be utilized in HER2 diagnosis. • Protein lysate array is a novel strategy to screen for highly specific antibody.« less

  7. Tribody [(HER2)2xCD16] Is More Effective Than Trastuzumab in Enhancing γδ T Cell and Natural Killer Cell Cytotoxicity Against HER2-Expressing Cancer Cells.

    PubMed

    Oberg, Hans H; Kellner, Christian; Gonnermann, Daniel; Sebens, Susanne; Bauerschlag, Dirk; Gramatzki, Martin; Kabelitz, Dieter; Peipp, Matthias; Wesch, Daniela

    2018-01-01

    An enhanced expression of human epidermal growth factor receptor 2 (HER2, ErbB2) often occurs in an advanced stage of breast, ovarian, gastric or esophageal cancer, and pancreatic ductal adenocarcinoma (PDAC). Commonly, HER2 expression is associated with poor clinical outcome or chemoresistance in ovarian and breast cancer patients. Treatment with humanized anti-HER2 monoclonal antibodies, such as trastuzumab or pertuzumab, has improved the outcome of patients with HER2-positive metastatic gastric or breast cancer, but not all patients benefit. In this study, the bispecific antibody [(HER2) 2 xCD16] in the tribody format was employed to re-direct CD16-expressing γδ T lymphocytes as well as natural killer (NK) cells to the tumor-associated cell surface antigen HER2 to enhance their cytotoxic anti-tumor activity. Tribody [(HER2) 2 xCD16] comprises two HER2-specific single chain fragment variable fused to a fragment antigen binding directed to the CD16 (FcγRIII) antigen expressed on γδ T cells and NK cells. Our results revealed the superiority of tribody [(HER2) 2 xCD16] compared to trastuzumab in triggering γδ T cell and NK cell-mediated lysis of HER2-expressing tumor cells, such as PDAC, breast cancer, and autologous primary ovarian tumors. The increased efficacy of [(HER2) 2 xCD16] can be explained by an enhanced degranulation of immune cells. Although CD16 expression was decreased on γδ T cells in several PDAC patients and the number of tumor-infiltrating NK cells and γδ T cells was impaired in ovarian cancer patients, [(HER2) 2 xCD16] selectively enhanced cytotoxicity of cells from these patients. Here, unique anti-tumor properties of tribody [(HER2) 2 xCD16] are identified which beyond addressing HER2 overexpressing solid tumors may allow to treat with similar immunoconstructs combined with the adoptive transfer of γδ T cells and NK cells refractory hematological malignancies. A major advantage of γδ T cells and NK cells in the transplant

  8. Tribody [(HER2)2xCD16] Is More Effective Than Trastuzumab in Enhancing γδ T Cell and Natural Killer Cell Cytotoxicity Against HER2-Expressing Cancer Cells

    PubMed Central

    Oberg, Hans H.; Kellner, Christian; Gonnermann, Daniel; Sebens, Susanne; Bauerschlag, Dirk; Gramatzki, Martin; Kabelitz, Dieter; Peipp, Matthias; Wesch, Daniela

    2018-01-01

    An enhanced expression of human epidermal growth factor receptor 2 (HER2, ErbB2) often occurs in an advanced stage of breast, ovarian, gastric or esophageal cancer, and pancreatic ductal adenocarcinoma (PDAC). Commonly, HER2 expression is associated with poor clinical outcome or chemoresistance in ovarian and breast cancer patients. Treatment with humanized anti-HER2 monoclonal antibodies, such as trastuzumab or pertuzumab, has improved the outcome of patients with HER2-positive metastatic gastric or breast cancer, but not all patients benefit. In this study, the bispecific antibody [(HER2)2xCD16] in the tribody format was employed to re-direct CD16-expressing γδ T lymphocytes as well as natural killer (NK) cells to the tumor-associated cell surface antigen HER2 to enhance their cytotoxic anti-tumor activity. Tribody [(HER2)2xCD16] comprises two HER2-specific single chain fragment variable fused to a fragment antigen binding directed to the CD16 (FcγRIII) antigen expressed on γδ T cells and NK cells. Our results revealed the superiority of tribody [(HER2)2xCD16] compared to trastuzumab in triggering γδ T cell and NK cell-mediated lysis of HER2-expressing tumor cells, such as PDAC, breast cancer, and autologous primary ovarian tumors. The increased efficacy of [(HER2)2xCD16] can be explained by an enhanced degranulation of immune cells. Although CD16 expression was decreased on γδ T cells in several PDAC patients and the number of tumor-infiltrating NK cells and γδ T cells was impaired in ovarian cancer patients, [(HER2)2xCD16] selectively enhanced cytotoxicity of cells from these patients. Here, unique anti-tumor properties of tribody [(HER2)2xCD16] are identified which beyond addressing HER2 overexpressing solid tumors may allow to treat with similar immunoconstructs combined with the adoptive transfer of γδ T cells and NK cells refractory hematological malignancies. A major advantage of γδ T cells and NK cells in the transplant situation of

  9. Anti-leukemic activity and tolerability of anti-human CD47 monoclonal antibodies

    PubMed Central

    Pietsch, E C; Dong, J; Cardoso, R; Zhang, X; Chin, D; Hawkins, R; Dinh, T; Zhou, M; Strake, B; Feng, P-H; Rocca, M; Santos, C Dos; Shan, X; Danet-Desnoyers, G; Shi, F; Kaiser, E; Millar, H J; Fenton, S; Swanson, R; Nemeth, J A; Attar, R M

    2017-01-01

    CD47, a broadly expressed cell surface protein, inhibits cell phagocytosis via interaction with phagocyte-expressed SIRPα. A variety of hematological malignancies demonstrate elevated CD47 expression, suggesting that CD47 may mediate immune escape. We discovered three unique CD47-SIRPα blocking anti-CD47 monoclonal antibodies (mAbs) with low nano-molar affinity to human and cynomolgus monkey CD47, and no hemagglutination and platelet aggregation activity. To characterize the anti-cancer activity elicited by blocking CD47, the mAbs were cloned into effector function silent and competent Fc backbones. Effector function competent mAbs demonstrated potent activity in vitro and in vivo, while effector function silent mAbs demonstrated minimal activity, indicating that blocking CD47 only leads to a therapeutic effect in the presence of Fc effector function. A non-human primate study revealed that the effector function competent mAb IgG1 C47B222-(CHO) decreased red blood cells (RBC), hematocrit and hemoglobin by >40% at 1 mg/kg, whereas the effector function silent mAb IgG2σ C47B222-(CHO) had minimal impact on RBC indices at 1 and 10 mg/kg. Taken together, our findings suggest that targeting CD47 is an attractive therapeutic anti-cancer approach. However, the anti-cancer activity observed with anti-CD47 mAbs is Fc effector dependent as are the side effects observed on RBC indices. PMID:28234345

  10. A phase I open-label dose-escalation study of the anti-HER3 monoclonal antibody LJM716 in patients with advanced squamous cell carcinoma of the esophagus or head and neck and HER2-overexpressing breast or gastric cancer.

    PubMed

    Reynolds, Kerry Lynn; Bedard, Philippe L; Lee, Se-Hoon; Lin, Chia-Chi; Tabernero, Josep; Alsina, Maria; Cohen, Ezra; Baselga, José; Blumenschein, George; Graham, Donna M; Garrido-Laguna, Ignacio; Juric, Dejan; Sharma, Sunil; Salgia, Ravi; Seroutou, Abdelkader; Tian, Xianbin; Fernandez, Rose; Morozov, Alex; Sheng, Qing; Ramkumar, Thiruvamoor; Zubel, Angela; Bang, Yung-Jue

    2017-09-12

    Human epidermal growth factor receptor 3 (HER3) is important in maintaining epidermal growth factor receptor-driven cancers and mediating resistance to targeted therapy. A phase I study of anti-HER3 monoclonal antibody LJM716 was conducted with the primary objective to identify the maximum tolerated dose (MTD) and/or recommended dose for expansion (RDE), and dosing schedule. Secondary objectives were to characterize safety/tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity. This open-label, dose-finding study comprised dose escalation, followed by expansion in patients with squamous cell carcinoma of the head and neck or esophagus, and HER2-overexpressing metastatic breast cancer or gastric cancer. During dose escalation, patients received LJM716 intravenous once weekly (QW) or every two weeks (Q2W), in 28-day cycles. An adaptive Bayesian logistic regression model was used to guide dose escalation and establish the RDE. Exploratory pharmacodynamic tumor studies evaluated modulation of HER3 signaling. Patients received LJM716 3-40 mg/kg QW and 20 mg/kg Q2W (54 patients; 36 patients at 40 mg/kg QW). No dose-limiting toxicities (DLTs) were reported during dose-escalation. One patient experienced two DLTs (diarrhea, hypokalemia [both grade 3]) in the expansion phase. The RDE was 40 mg/kg QW, providing drug levels above the preclinical minimum effective concentration. One patient with gastric cancer had an unconfirmed partial response; 17/54 patients had stable disease, two lasting >30 weeks. Down-modulation of phospho-HER3 was observed in paired tumor samples. LJM716 was well tolerated; the MTD was not reached, and the RDE was 40 mg/kg QW. Further development of LJM716 is ongoing. Clinicaltrials.gov registry number NCT01598077 (registered on 4 May, 2012).

  11. Emerging treatments for HER2-positive early-stage breast cancer: focus on neratinib.

    PubMed

    Kourie, Hampig Raphael; El Rassy, Elie; Clatot, Florian; de Azambuja, Evandro; Lambertini, Matteo

    2017-01-01

    Over the last decades, a better understanding of breast cancer heterogeneity provided tools for a biologically based personalization of anticancer treatments. In particular, the overexpression of the human epidermal growth factor receptor 2 (HER2) by tumor cells provided a specific target in these HER2-positive tumors. The development of the monoclonal antibody trastuzumab, and its approval in 1998 for the treatment of patients with metastatic disease, radically changed the natural history of this aggressive subtype of breast cancer. These findings provided strong support for the continuous research in targeting the HER2 pathway and implementing the development of new anti-HER2 targeted agents. Besides trastuzumab, a series of other anti-HER2 agents have been developed and are currently being explored for the treatment of breast cancer patients, including those diagnosed with early-stage disease. Among these agents, neratinib, an oral tyrosine kinase inhibitor that irreversibly inhibits HER1, HER2, and HER4 at the intracellular level, has shown promising results, including when administered to patients previously exposed to trastuzumab-based treatment. This article aims to review the available data on the role of the HER2 pathway in breast cancer and on the different targeted agents that have been studied or are currently under development for the treatment of patients with early-stage HER2-positive disease with a particular focus on neratinib.

  12. Emerging treatments for HER2-positive early-stage breast cancer: focus on neratinib

    PubMed Central

    Kourie, Hampig Raphael; El Rassy, Elie; Clatot, Florian; de Azambuja, Evandro; Lambertini, Matteo

    2017-01-01

    Over the last decades, a better understanding of breast cancer heterogeneity provided tools for a biologically based personalization of anticancer treatments. In particular, the overexpression of the human epidermal growth factor receptor 2 (HER2) by tumor cells provided a specific target in these HER2-positive tumors. The development of the monoclonal antibody trastuzumab, and its approval in 1998 for the treatment of patients with metastatic disease, radically changed the natural history of this aggressive subtype of breast cancer. These findings provided strong support for the continuous research in targeting the HER2 pathway and implementing the development of new anti-HER2 targeted agents. Besides trastuzumab, a series of other anti-HER2 agents have been developed and are currently being explored for the treatment of breast cancer patients, including those diagnosed with early-stage disease. Among these agents, neratinib, an oral tyrosine kinase inhibitor that irreversibly inhibits HER1, HER2, and HER4 at the intracellular level, has shown promising results, including when administered to patients previously exposed to trastuzumab-based treatment. This article aims to review the available data on the role of the HER2 pathway in breast cancer and on the different targeted agents that have been studied or are currently under development for the treatment of patients with early-stage HER2-positive disease with a particular focus on neratinib. PMID:28744140

  13. Development of anti-HER2 conjugated ICG-loaded polymeric nanoparticles for targeted optical imaging of ovarian cancer

    NASA Astrophysics Data System (ADS)

    Bahmani, Baharak; Vullev, Valentine; Anvari, Bahman

    2012-03-01

    Targeted delivery of therapeutic and imaging agents using surface modified nanovectors has been explored immensely in recent years. The growing demand for site-specific and efficient delivery of nanovectors entails stable surface conjugation of targeting moieties. We have developed a polymeric nanocapsule doped with Indocyanine green (ICG) with potential for targeted and deep tissue optical imaging and phototherapy. Our ICG-loaded nanocapsules (ICG-NCs) have potential for covalent coupling of various targeting moieties and materials due to presence of amine groups on the surface. Here, we covalently bioconjugate polyethylene glycol(PEG)-coated ICG-NCs with monoclonal antibody against HER2 through reductive amination-mediated procedures. The irreversible and stable bonds are formed between anti- EGFR and aldehyde termini of PEG chains on the surface of ICG-NCs. We confirm the uptake of conjugated ICG-NCs by ovarian cancer cells over-expressing HER2 using fluorescent confocal microscopy. The proposed process for covalent attachment of anti-HER2 to PEGylated ICG-NCs can be used as a methodology for bioconjugation of various antibodies to such nano-constrcuts, and provides the capability to use these optically active nano-probes for targeted optical imaging of ovarian and other cancer types.

  14. Generation and testing anti-influenza human monoclonal antibodies in a new humanized mouse model (DRAGA: HLA-A2. HLA-DR4. Rag1 KO. IL-2Rγc KO. NOD).

    PubMed

    Mendoza, Mirian; Ballesteros, Angela; Qiu, Qi; Pow Sang, Luis; Shashikumar, Soumya; Casares, Sofia; Brumeanu, Teodor-D

    2018-02-01

    Pandemic outbreaks of influenza type A viruses have resulted in numerous fatalities around the globe. Since the conventional influenza vaccines (CIV) provide less than 20% protection for individuals with weak immune system, it has been considered that broadly cross-neutralizing antibodies may provide a better protection. Herein, we showed that a recently generated humanized mouse (DRAGA mouse; HLA-A2. HLA-DR4. Rag1KO. IL-2Rgc KO. NOD) that lacks the murine immune system and expresses a functional human immune system can be used to generate cross-reactive, human anti-influenza monoclonal antibodies (hu-mAb). DRAGA mouse was also found to be suitable for influenza virus infection, as it can clear a sub-lethal infection and sustain a lethal infection with PR8/A/34 influenza virus. The hu-mAbs were designed for targeting a human B-cell epitope ( 180 WGIHHPPNSKEQ QNLY 195 ) of hemagglutinin (HA) envelope protein of PR8/A/34 (H1N1) virus with high homology among seven influenza type A viruses. A single administration of HA 180-195 specific hu-mAb in PR8-infected DRAGA mice significantly delayed the lethality by reducing the lung damage. The results demonstrated that DRAGA mouse is a suitable tool to (i) generate heterotype cross-reactive, anti-influenza human monoclonal antibodies, (ii) serve as a humanized mouse model for influenza infection, and (iii) assess the efficacy of anti-influenza antibody-based therapeutics for human use.

  15. Predominant antitumor effects by fully human anti-TRAIL-receptor2 (DR5) monoclonal antibodies in human glioma cells in vitro and in vivo

    PubMed Central

    Nagane, Motoo; Shimizu, Saki; Mori, Eiji; Kataoka, Shiro; Shiokawa, Yoshiaki

    2010-01-01

    Tumor necrosis factor–related apoptosis-inducing ligand (TRAIL/Apo2 L) preferentially induces apoptosis in human tumor cells through its cognate death receptors DR4 or DR5, thereby being investigated as a potential agent for cancer therapy. Here, we applied fully human anti-human TRAIL receptor monoclonal antibodies (mAbs) to specifically target one of death receptors for TRAIL in human glioma cells, which could also reduce potential TRAIL-induced toxicity in humans. Twelve human glioma cell lines treated with several fully human anti-human TRAIL receptor mAbs were sensitive to only anti-DR5 mAbs, whereas they were totally insensitive to anti-DR4 mAb. Treatment with anti-DR5 mAbs exerted rapid cytotoxicity and lead to apoptosis induction. The cellular sensitivity was closely associated with cell-surface expression of DR5. Expression of c-FLIPL, Akt, and Cyclin D1 significantly correlated with sensitivity to anti-DR5 mAbs. Primary cultures of glioma cells were also relatively resistant to anti-DR5 mAbs, exhibiting both lower DR5 and higher c-FLIPL expression. Downregulation of c-FLIPL expression resulted in the sensitization of human glioma cells to anti-DR5 mAbs, whereas overexpression of c-FLIPL conferred resistance to anti-DR5 mAb. Treatment of tumor-burden nude mice with the direct agonist anti-DR5 mAb KMTR2 significantly suppressed growth of subcutaneous glioma xenografts leading to complete regression. Similarly, treatment of nude mice bearing intracerebral glioma xenografts with KMTR2 significantly elongated lifespan without tumor recurrence. These results suggest that DR5 is the predominant TRAIL receptor mediating apoptotic signals in human glioma cells, and sensitivity to anti-DR5 mAbs was determined at least in part by the expression level of c-FLIPL and Akt. Specific targeting of death receptor pathway through DR5 using fully human mAbs might provide a novel therapeutic strategy for intractable malignant gliomas. PMID:20511188

  16. Upregulation of ER signaling as an adaptive mechanism of cell survival in HER2-positive breast tumors treated with anti-HER2 therapy

    PubMed Central

    Giuliano, Mario; Hu, Huizhong; Wang, Yen-Chao; Fu, Xiaoyong; Nardone, Agostina; Herrera, Sabrina; Mao, Sufeng; Contreras, Alejandro; Gutierrez, Carolina; Wang, Tao; Hilsenbeck, Susan G.; De Angelis, Carmine; Wang, Nicholas J.; Heiser, Laura M.; Gray, Joe W.; Lopez-Tarruella, Sara; Pavlick, Anne C.; Trivedi, Meghana V.; Chamness, Gary C.; Chang, Jenny C.; Osborne, C. Kent; Rimawi, Mothaffar F.; Schiff, Rachel

    2015-01-01

    Purpose To investigate the direct effect and therapeutic consequences of epidermal growth factor receptor 2 (HER2)-targeting therapy on expression of estrogen receptor (ER) and Bcl2 in preclinical models and clinical tumor samples. Experimental design Archived xenograft tumors from two preclinical models (UACC812 and MCF7/HER2-18) treated with ER and HER2-targeting therapies, and also HER2+ clinical breast cancer specimens collected in a lapatinib neoadjuvant trial (baseline and week 2 post treatment), were used. Expression levels of ER and Bcl2 were evaluated by immunohistochemistry and western blot. The effects of Bcl2 and ER inhibition, by ABT-737 and fulvestrant respectively, were tested in parental versus lapatinib-resistant UACC812 cells in vitro. Results Expression of ER and Bcl2 was significantly increased in xenograft tumors with acquired resistance to anti-HER2 therapy, compared with untreated tumors, in both preclinical models (UACC812: ER p=0.0014; Bcl2 p<0.001. MCF7/HER2-18: ER p=0.0007; Bcl2 p=0.0306). In the neoadjuvant clinical study, lapatinib treatment for two weeks was associated with parallel upregulation of ER and Bcl2 (Spearman’s coefficient: 0.70; p=0.0002). Importantly, 18% of tumors originally ER-negative (ER−) converted to ER+ upon anti-HER2 therapy. In ER−/HER2+ MCF7/HER2-18 xenografts, ER re-expression was primarily observed in tumors responding to potent combination of anti-HER2 drugs. Estrogen deprivation added to this anti-HER2 regimen significantly delayed tumor progression (p=0.018). In the UACC812 cells, fulvestrant, but not ABT-737, was able to completely inhibit anti-HER2-resistant growth (p<0.0001). Conclusion HER2 inhibition can enhance or restore ER expression with parallel Bcl2 upregulation, representing an ER-dependent survival mechanism potentially leading to anti-HER2 resistance. PMID:26015514

  17. Assessment of the systemic distribution of a bioconjugated anti-Her2 magnetic nanoparticle in a breast cancer model by means of magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Huerta-Núñez, L. F. E.; Villanueva-Lopez, G. Cleva; Morales-Guadarrama, A.; Soto, S.; López, J.; Silva, J. G.; Perez-Vielma, N.; Sacristán, E.; Gudiño-Zayas, Marco E.; González, C. A.

    2016-09-01

    The aim of this study was to determine the systemic distribution of magnetic nanoparticles of 100 nm diameter (MNPs) coupled to a specific monoclonal antibody anti-Her2 in an experimental breast cancer (BC) model. The study was performed in two groups of Sprague-Dawley rats: control ( n = 6) and BC chemically induced ( n = 3). Bioconjugated "anti-Her2-MNPs" were intravenously administered, and magnetic resonance imaging (MRI) monitored its systemic distribution at seven times after administration. Non-heme iron presence associated with the location of the bioconjugated anti-Her2-MNPs in splenic, hepatic, cardiac and tumor tissues was detected by Perl's Prussian blue (PPB) stain. Optical density measurements were used to semiquantitatively determine the iron presence in tissues on the basis of a grayscale values integration of T1 and T2 MRI sequence images. The results indicated a delayed systemic distribution of MNPs in cancer compared to healthy conditions with a maximum concentration of MNPs in cancer tissue at 24 h post-infusion.

  18. Novel agents that downregulate EGFR, HER2, and HER3 in parallel

    PubMed Central

    Ferreira, Renan Barroso; Law, Mary Elizabeth; Jahn, Stephan Christopher; Davis, Bradley John; Heldermon, Coy Don; Reinhard, Mary; Castellano, Ronald Keith; Law, Brian Keith

    2015-01-01

    EGFR, HER2, and HER3 contribute to the initiation and progression of human cancers, and are therapeutic targets for monoclonal antibodies and tyrosine kinase inhibitors. An important source of resistance to these agents arises from functional redundancy among EGFR, HER2, and HER3. EGFR family members contain conserved extracellular structures that are stabilized by disulfide bonds. Compounds that disrupt extracellular disulfide bonds could inactivate EGFR, HER2, and HER3 in unison. Here we describe the identification of compounds that kill breast cancer cells that overexpress EGFR or HER2. Cell death parallels downregulation of EGFR, HER2, and HER3. These compounds disrupt disulfide bonds and are termed Disulfide Bond Disrupting Agents (DDAs). DDA RBF3 exhibits anticancer efficacy in vivo at 40 mg/kg without evidence of toxicity. DDAs may complement existing EGFR-, HER2-, and HER3-targeted agents that function through alternate mechanisms of action, and combination regimens with these existing drugs may overcome therapeutic resistance. PMID:25865227

  19. Construction and evaluation of a novel humanized HER2-specific chimeric receptor

    PubMed Central

    2014-01-01

    Introduction The human epidermal growth factor receptor 2 (HER2) represents one of the most studied tumor-associated antigens (TAAs) for cancer immunotherapy. The monoclonal antibody (mAb) trastuzumab has improved the outcomes of patients with HER2+ breast cancer. However, a large number of HER2+ tumors are not responsive to, or become resistant to, trastuzumab-based therapy, and thus more effective therapies targeting HER2 are needed. Methods HER2-specific T cells were generated by the transfer of genes that encode chimeric antigen receptor (CAR). Using a multistep overlap extension PCR method, we constructed a novel, humanized HER2 CAR-containing, chA21 single-chain variable fragment (scFv) region of antigen-specific mAb and T-cell intracellular signaling chains made up of CD28 and CD3ζ. An interferon γ and interleukin 2 enzyme-linked immunosorbent assay and a chromium-51 release assay were used to evaluate the antitumor immune response of CAR T cells in coculture with tumor cells. Furthermore, SKBR3 tumor–bearing nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice were treated with HER2 CAR T cells to evaluate antitumor activity. Human CD3+ T cell accumulation in tumor xenograft was detected by immunohistochemistry. Results chA21-28z CAR was successfully constructed, and both CD4+ and CD8+ T cells were transduced. The expanded HER2 CAR T cells expressed a central memory phenotype and specifically reacted against HER2+ tumor cell lines. Furthermore, the SKBR3 tumor xenograft model revealed that HER2 CAR T cells significantly inhibited tumor growth in vivo. Immunohistochemical analysis showed robust accumulation of human CD3+ T cells in regressing SKBR3 lesions. Conclusions The results of this study show that novel chA21 scFv-based, HER2-specific CAR T cells not only recognized and killed HER2+ breast and ovarian cancer cells ex vivo but also induced regression of experimental breast cancer in vivo. Our data support further exploration of the

  20. Use of chemotherapy plus a monoclonal antibody against HER2 for metastatic breast cancer that overexpresses HER2.

    PubMed

    Slamon, D J; Leyland-Jones, B; Shak, S; Fuchs, H; Paton, V; Bajamonde, A; Fleming, T; Eiermann, W; Wolter, J; Pegram, M; Baselga, J; Norton, L

    2001-03-15

    The HER2 gene, which encodes the growth factor receptor HER2, is amplified and HER2 is overexpressed in 25 to 30 percent of breast cancers, increasing the aggressiveness of the tumor. We evaluated the efficacy and safety of trastuzumab, a recombinant monoclonal antibody against HER2, in women with metastatic breast cancer that overexpressed HER2. We randomly assigned 234 patients to receive standard chemotherapy alone and 235 patients to receive standard chemotherapy plus trastuzumab. Patients who had not previously received adjuvant (postoperative) therapy with an anthracycline were treated with doxorubicin (or epirubicin in the case of 36 women) and cyclophosphamide alone (138 women) or with trastuzumab (143 women). Patients who had previously received adjuvant anthracycline were treated with paclitaxel alone (96 women) or paclitaxel with trastuzumab (92 women). The addition of trastuzumab to chemotherapy was associated with a longer time to disease progression (median, 7.4 vs. 4.6 months; P<0.001), a higher rate of objective response (50 percent vs. 32 percent, P<0.001), a longer duration of response (median, 9.1 vs. 6.1 months; P<0.001), a lower rate of death at 1 year (22 percent vs. 33 percent, P=0.008), longer survival (median survival, 25.1 vs. 20.3 months; P=0.01), and a 20 percent reduction in the risk of death. The most important adverse event was cardiac dysfunction of New York Heart Association class III or IV, which occurred in 27 percent of the group given an anthracycline, cyclophosphamide, and trastuzumab; 8 percent of the group given an anthracycline and cyclophosphamide alone; 13 percent of the group given paclitaxel and trastuzumab; and 1 percent of the group given paclitaxel alone. Although the cardiotoxicity was potentially severe and, in some cases, life-threatening, the symptoms generally improved with standard medical management. Trastuzumab increases the clinical benefit of first-line chemotherapy in metastatic breast cancer that

  1. Detection of Signal Regulatory Protein α in Saimiri sciureus (Squirrel Monkey) by Anti-Human Monoclonal Antibody

    PubMed Central

    de Souza, Hugo Amorim dos Santos; Costa-Correa, Edmar Henrique; Bianco-Junior, Cesare; Andrade, Márcia Cristina Ribeiro; Lima-Junior, Josué da Costa; Pratt-Riccio, Lilian Rose; Daniel-Ribeiro, Cláudio Tadeu; Totino, Paulo Renato Rivas

    2017-01-01

    Non-human primates (NHP) are suitable models for studying different aspects of the human system, including pathogenesis and protective immunity to many diseases. However, the lack of specific immunological reagents for neo-tropical monkeys, such as Saimiri sciureus, is still a major factor limiting studies in these models. An alternative strategy to circumvent this obstacle has been the selection of immunological reagents directed to humans, which present cross-reactivity with NHP molecules. In this context and considering the key role of inhibitory immunoreceptors—such as the signal regulatory protein α (SIRPα)—in the regulation of immune responses, in the present study, we attempted to evaluate the ability of anti-human SIRPα monoclonal antibodies to recognize SIRPα in antigen-presenting S. sciureus peripheral blood mononuclear cells (PBMC). As shown by flow cytometry analysis, the profile of anti-SIRPα staining as well as the levels of SIRPα-positive cells in PBMC from S. sciureus were similar to those observed in human PBMC. Furthermore, using anti-SIRPα monoclonal antibody, it was possible to detect a decrease of the SIRPα levels on surface of S. sciureus cells after in vitro stimulation with lipopolysaccharides. Finally, using computed-based analysis, we observed a high degree of conservation of SIRPα across six species of primates and the presence of shared epitopes in the extracellular domain between humans and Saimiri genus that could be targeted by antibodies. In conclusion, we have identified a commercially available anti-human monoclonal antibody that is able to detect SIRPα of S. sciureus monkeys and that, therefore, can facilitate the study of the immunomodulatory role of SIRPα when S. sciureus is used as a model. PMID:29312325

  2. Immunotherapy of Alzheimer's disease (AD): from murine models to anti-amyloid beta (Abeta) human monoclonal antibodies.

    PubMed

    Geylis, Valeria; Steinitz, Michael

    2006-01-01

    The deposition of amyloid beta (Abeta) protein is a key pathological feature in Alzheimer's disease (AD). In murine models of AD, both active and passive immunization against Abeta induce a marked reduction in amyloid brain burden and an improvement in cognitive functions. Preliminary results of a prematurely terminated clinical trial where AD patients were actively vaccinated with aggregated Abeta bear resemblance to those documented in murine models. Passive immunization of AD patients with anti-Abeta antibodies, in particular human antibodies, is a strategy that provides a more cautious management and control of any undesired side effects. Sera of all healthy adults contain anti-Abeta IgG autoimmune antibodies. Hence antigen-committed human B-cells are easily immortalized by Epstein-Barr virus (EBV) into anti-Abeta secreting cell lines. Two anti-Abeta human monoclonal antibodies which we recently prepared bind to the N-terminus of Abeta peptide and were shown to stain amyloid plaques in non-fixed brain sections from an AD patient. It is anticipated that specifically selected anti-Abeta human monoclonal antibodies could reduce and inhibit deposits of amyloid in brain while avoiding the cognitive decline that characterizes AD. In the future, this type of antibody may prove to be a promising immune therapy for the disease.

  3. Pertuzumab: a new targeted therapy for HER2-positive metastatic breast cancer.

    PubMed

    Malenfant, Stephanie J; Eckmann, Karen R; Barnett, Chad M

    2014-01-01

    Trastuzumab, a humanized monoclonal antibody, has become an important targeted therapy for patients with all stages of human epidermal growth factor receptor-2 (HER2)-positive breast cancer. However, primary and acquired resistance to trastuzumab remains a significant problem. Pertuzumab, a humanized monoclonal antibody that binds to a domain of the HER2 receptor separate from trastuzumab, may have the potential to overcome trastuzumab resistance. Clinical trials have shown that pertuzumab can be effectively combined with other biologic therapy or chemotherapy in patients with metastatic HER2-positive breast cancer. Pertuzumab is relatively well tolerated with minimal increases in hematologic and cardiac toxicity observed when added to trastuzumab and/or docetaxel. In addition to becoming the standard of care in combination with docetaxel and trastuzumab in patients with newly diagnosed HER2-positive metastatic breast cancer, clinical trials continue to evaluate pertuzumab in combination with other targeted therapy, chemotherapy, and in patients with early stage breast cancer. These trials will help to further determine the role of pertuzumab in the treatment of HER2-positive breast cancer. © 2013 Pharmacotherapy Publications, Inc.

  4. Suppressors for Human Epidermal Growth Factor Receptor 2/4 (HER2/4): A New Family of Anti-Toxoplasmic Agents in ARPE-19 Cells

    PubMed Central

    Kim, Yeong Hoon; Bhatt, Lokraj; Ahn, Hye-Jin; Yang, Zhaoshou; Lee, Won-Kyu; Nam, Ho-Woo

    2017-01-01

    The effects of tyrosine kinase inhibitors (TKIs) were evaluated on growth inhibition of intracellular Toxoplasma gondii in host ARPE-19 cells. The number of tachyzoites per parasitophorous vacuolar membrane (PVM) was counted after treatment with TKIs. T. gondii protein expression was assessed by western blot. Immunofluorescence assay was performed using Programmed Cell Death 4 (PDCD4) and T. gondii GRA3 antibodies. The TKIs were divided into 3 groups; non-epidermal growth factor receptor (non-EGFR), anti-human EGFR 2 (anti-HER2), and anti-HER2/4 TKIs, respectively. Group I TKIs (nintedanib, AZD9291, and sunitinib) were unable to inhibit proliferation without destroying host cells. Group II TKIs (lapatinib, gefitinib, erlotinib, and AG1478) inhibited proliferation up to 98% equivalent to control pyrimethamine (5 μM) at 20 μM and higher, without affecting host cells. Group III TKIs (neratinib, dacomitinib, afatinib, and pelitinib) inhibited proliferation up to 98% equivalent to pyrimethamine at 1–5 μM, but host cells were destroyed at 10–20 μM. In Group I, TgHSP90 and SAG1 inhibitions were weak, and GRA3 expression was moderately inhibited. In Group II, TgHSP90 and SAG1 expressions seemed to be slightly enhanced, while GRA3 showed none to mild inhibition; however, AG1478 inhibited all proteins moderately. Protein expression was blocked in Group III, comparable to pyrimethamine. PDCD4 and GRA3 were well localized inside the nuclei in Group I, mildly disrupted in Group II, and were completely disrupted in Group III. This study suggests the possibility of a vital T. gondii TK having potential HER2/4 properties, thus anti-HER2/4 TKIs may inhibit intracellular parasite proliferation with minimal adverse effects on host cells. PMID:29103264

  5. Suppressors for Human Epidermal Growth Factor Receptor 2/4 (HER2/4): A New Family of Anti-Toxoplasmic Agents in ARPE-19 Cells.

    PubMed

    Kim, Yeong Hoon; Bhatt, Lokraj; Ahn, Hye-Jin; Yang, Zhaoshou; Lee, Won-Kyu; Nam, Ho-Woo

    2017-10-01

    The effects of tyrosine kinase inhibitors (TKIs) were evaluated on growth inhibition of intracellular Toxoplasma gondii in host ARPE-19 cells. The number of tachyzoites per parasitophorous vacuolar membrane (PVM) was counted after treatment with TKIs. T. gondii protein expression was assessed by western blot. Immunofluorescence assay was performed using Programmed Cell Death 4 (PDCD4) and T. gondii GRA3 antibodies. The TKIs were divided into 3 groups; non-epidermal growth factor receptor (non-EGFR), anti-human EGFR 2 (anti-HER2), and anti-HER2/4 TKIs, respectively. Group I TKIs (nintedanib, AZD9291, and sunitinib) were unable to inhibit proliferation without destroying host cells. Group II TKIs (lapatinib, gefitinib, erlotinib, and AG1478) inhibited proliferation up to 98% equivalent to control pyrimethamine (5 μM) at 20 μM and higher, without affecting host cells. Group III TKIs (neratinib, dacomitinib, afatinib, and pelitinib) inhibited proliferation up to 98% equivalent to pyrimethamine at 1-5 μM, but host cells were destroyed at 10-20 μM. In Group I, TgHSP90 and SAG1 inhibitions were weak, and GRA3 expression was moderately inhibited. In Group II, TgHSP90 and SAG1 expressions seemed to be slightly enhanced, while GRA3 showed none to mild inhibition; however, AG1478 inhibited all proteins moderately. Protein expression was blocked in Group III, comparable to pyrimethamine. PDCD4 and GRA3 were well localized inside the nuclei in Group I, mildly disrupted in Group II, and were completely disrupted in Group III. This study suggests the possibility of a vital T. gondii TK having potential HER2/4 properties, thus anti-HER2/4 TKIs may inhibit intracellular parasite proliferation with minimal adverse effects on host cells.

  6. Human Papillomavirus Regulates HER3 Expression in Head and Neck Cancer: Implications for Targeted HER3 Therapy in HPV+ Patients.

    PubMed

    Brand, Toni M; Hartmann, Stefan; Bhola, Neil E; Peyser, Noah D; Li, Hua; Zeng, Yan; Isaacson Wechsler, Erin; Ranall, Max V; Bandyopadhyay, Sourav; Duvvuri, Umamaheswar; LaVallee, Theresa M; Jordan, Richard C K; Johnson, Daniel E; Grandis, Jennifer R

    2017-06-15

    Purpose: Human papillomavirus (HPV) 16 plays an etiologic role in a growing subset of head and neck squamous cell carcinomas (HNSCC), where viral expression of the E6 and E7 oncoproteins is necessary for tumor growth and maintenance. Although patients with HPV + tumors have a more favorable prognosis, there are currently no HPV-selective therapies. Recent studies identified differential receptor tyrosine kinase (RTK) profiles in HPV + versus HPV - tumors. One such RTK, HER3, is overexpressed and interacts with phosphoinositide-3-kinase (PI3K) in HPV + tumors. Therefore, we investigated the role of HPV oncoproteins in regulating HER3-mediated signaling and determined whether HER3 could be a molecular target in HPV + HNSCC. Experimental Design: HER3 was investigated as a molecular target in HPV + HNSCC using established cell lines, patient-derived xenografts (PDX), and human tumor specimens. A mechanistic link between HPV and HER3 was examined by augmenting E6 and E7 expression levels in HNSCC cell lines. The dependency of HPV + and HPV - HNSCC models on HER3 was evaluated with anti-HER3 siRNAs and the clinical stage anti-HER3 monoclonal antibody KTN3379. Results: HER3 was overexpressed in HPV + HNSCC, where it was associated with worse overall survival in patients with pharyngeal cancer. Further investigation indicated that E6 and E7 regulated HER3 protein expression and downstream PI3K pathway signaling. Targeting HER3 with siRNAs or KTN3379 significantly inhibited the growth of HPV + cell lines and PDXs. Conclusions: This study uncovers a direct relationship between HPV infection and HER3 in HNSCC and provides a rationale for the clinical evaluation of targeted HER3 therapy for the treatment of HPV + patients. Clin Cancer Res; 23(12); 3072-83. ©2016 AACR . ©2016 American Association for Cancer Research.

  7. Remarkable response with pembrolizumab plus albumin-bound paclitaxel in 2 cases of HER2-positive metastatic breast cancer who have failed to multi-anti-HER2 targeted therapy.

    PubMed

    Li, Bian; Tao, Wang; Shao-Hua, Zhang; Ze-Rui, Qu; Fu-Quan, Jin; Fan, Li; Ze-Fei, Jiang

    2018-04-03

    In clinical practice, one subgroup patients of breast cancer might have developed resistance to multi-anti-HER2 targeted drugs(trastuzumab, lapatinib and/or T-DM1) and can not benefit from the anti-HER2 targeted therapy continuously. We attempt to change the next therapic way for these patients. Two patients with metastatic breast cancer who have failed to multi-anti-HER2 targeted therapy were treated with pembrolizumab (2 mg/Kg, day1) plus albumin-bound paclitaxel (125 mg/m 2 , day1,8) every 3 weeks. CT evaluation and HER2 ECD test were performed every 2 cycles. Both of the two patients achieved remarkable response with Partial Remission (PR), meanwhile serum HER2 ECD levels (the upper normal limit is 15 ng/ml) showed a remarkable decreases(compared to the base line decreases 75% and 60% respectively). The results indicate that regimen of pembrolizumab combination with albumin-bound paclitaxel might produce response in patients with HER2-positive metastatic breast cancer who have failed to multi-anti-HER2 targeted therapy.

  8. A human anti-dsDNA monoclonal antibody caused hyaline thrombi formation in kidneys of ‘leaky’ SCID mice

    PubMed Central

    Mason, L J; Ravirajan, C T; Latchman, D S; Isenberg, D A

    2001-01-01

    There are few studies assessing the pathogenicity of human monoclonal anti-DNA antibodies. The use of SCID mice avoids the problem of rejection of the human hybridoma cells thus allowing in vivo assessment of human immunoglobulins. Using electron microscopy we have shown that the human IgG anti-dsDNA monoclonal antibody, RH14, is nephritogenic in SCID mice, causing morphological changes in the kidney due to immunoglobulin deposition. The problem with using SCID mice is that they have an abnormal immune system; normally they are used at about 2 months of age, at which time they have virtually no functional T or B cells. It is known that older SCID mice become increasingly ‘leaky’, that is they develop some mature lymphocyte clones. Our aim was to assess if implanting anti-DNA antibodies into older ‘leaky’ SCID mice would result in pathology which was observable by light microscopy. Eight-month-old SCID mice were implanted with human hybridoma cells secreting either RH14 an anti-dsDNA IgG, CL24, an antiphospholipid antibody or an irrelevant human IgG control. As previously, RH14 deposited in the kidney and caused proteinuria but unexpectedly we also observed hyaline thrombi in the kidney glomeruli and peritubular capillaries. These thrombi occurred only in the case of RH14 implanted mice and were found to stain positively for human IgG and fibrin. However, apart from the interesting thrombi, we did not observe any greater pathological damage resulting from the anti-dsDNA antibody deposition than we had seen in the younger mice; indeed, the electron microscopic findings were more limited. PMID:11678910

  9. Effects of simultaneous knockdown of HER2 and PTK6 on malignancy and tumor progression in human breast cancer cells.

    PubMed

    Ludyga, Natalie; Anastasov, Natasa; Rosemann, Michael; Seiler, Jana; Lohmann, Nadine; Braselmann, Herbert; Mengele, Karin; Schmitt, Manfred; Höfler, Heinz; Aubele, Michaela

    2013-04-01

    Breast cancer is the most common malignancy in women of the Western world. One prominent feature of breast cancer is the co- and overexpression of HER2 and protein tyrosine kinase 6 (PTK6). According to the current clinical cancer therapy guidelines, HER2-overexpressing tumors are routinely treated with trastuzumab, a humanized monoclonal antibody targeting HER2. Approximately, 30% of HER2-overexpressing breast tumors at least initially respond to the anti-HER2 therapy, but a subgroup of these tumors develops resistance shortly after the administration of trastuzumab. A PTK6-targeted therapy does not yet exist. Here, we show for the first time that the simultaneous knockdown in vitro, compared with the single knockdown of HER2 and PTK6, in particular in the trastuzumab-resistant JIMT-1 cells, leads to a significantly decreased phosphorylation of crucial signaling proteins: mitogen-activated protein kinase 1/3 (MAPK 1/3, ERK 1/2) and p38 MAPK, and (phosphatase and tensin homologue deleted on chromosome ten) PTEN that are involved in tumorigenesis. In addition, dual knockdown strongly reduced the migration and invasion of the JIMT-1 cells. Moreover, the downregulation of HER2 and PTK6 led to an induction of p27, and the dual knockdown significantly diminished cell proliferation in JIMT-1 and T47D cells. In vivo experiments showed significantly reduced levels of tumor growth following HER2 or PTK6 knockdown. Our results indicate a novel strategy also for the treatment of trastuzumab resistance in tumors. Thus, the inhibition of these two signaling proteins may lead to a more effective control of breast cancer. ©2013 AACR.

  10. Near-infrared quantum dots for HER2 localization and imaging of cancer cells.

    PubMed

    Rizvi, Sarwat B; Rouhi, Sepideh; Taniguchi, Shohei; Yang, Shi Yu; Green, Mark; Keshtgar, Mo; Seifalian, Alexander M

    2014-01-01

    Quantum dots are fluorescent nanoparticles with unique photophysical properties that allow them to be used as diagnostic, therapeutic, and theranostic agents, particularly in medical and surgical oncology. Near-infrared-emitting quantum dots can be visualized in deep tissues because the biological window is transparent to these wavelengths. Their small sizes and free surface reactive groups that can be conjugated to biomolecules make them ideal probes for in vivo cancer localization, targeted chemotherapy, and image-guided cancer surgery. The human epidermal growth factor receptor 2 gene (HER2/neu) is overexpressed in 25%-30% of breast cancers. The current methods of detection for HER2 status, including immunohistochemistry and fluorescence in situ hybridization, are used ex vivo and cannot be used in vivo. In this paper, we demonstrate the application of near-infrared-emitting quantum dots for HER2 localization in fixed and live cancer cells as a first step prior to their in vivo application. Near-infrared-emitting quantum dots were characterized and their in vitro toxicity was established using three cancer cell lines, ie, HepG2, SK-BR-3 (HER2-overexpressing), and MCF7 (HER2-underexpressing). Mouse antihuman anti-HER2 monoclonal antibody was conjugated to the near-infrared-emitting quantum dots. In vitro toxicity studies showed biocompatibility of SK-BR-3 and MCF7 cell lines with near-infrared-emitting quantum dots at a concentration of 60 μg/mL after one hour and 24 hours of exposure. Near-infrared-emitting quantum dot antiHER2-antibody bioconjugates successfully localized HER2 receptors on SK-BR-3 cells. Near-infrared-emitting quantum dot bioconjugates can be used for rapid localization of HER2 receptors and can potentially be used for targeted therapy as well as image-guided surgery.

  11. Cardiotoxicity of novel HER2-targeted therapies.

    PubMed

    Sendur, Mehmet A N; Aksoy, Sercan; Altundag, Kadri

    2013-08-01

    Trastuzumab, an anti-HER2 humanized monoclonal antibody, is the standard treatment for both early and metastatic HER2-positive breast cancer. In addition to other chemotherapeutic agents, trastuzumab significantly improves response rate and survival in HER2-positive early and metastatic breast cancer. Although it is well known that trastuzumab therapy is closely associated with both symptomatic and asymptomatic cardiotoxicity, less is known about novel HER2-targeted therapies. The aim of this review is to discuss the cardiac safety data from recent studies of novel anti-HER2 drugs other than trastuzumab. Novel HER2-targeted therapies showed favorable results in HER2 positive metastatic breast cancer patients. Pubmed database, ASCO and San Antonio Breast Cancer Symposium Meeting abstracts were searched until January 2013 using the following search keywords; 'trastuzumab, trastuzumab cardiotoxicity, HER-2 targeted therapies, lapatinib, pertuzumab, trastuzumab emtansine, afatinib and neratinib'; papers which were considered relevant for the aim of this review were selected by the authors. Lapatinib, pertuzumab, T-DM1, neratinib and afatinib molecules are evaluated in the study. In a comprehensive analysis, 3689 lapatinib treated patients enrolled in 49 trials; asymptomatic cardiac events were reported in 53 patients (1.4%) and symptomatic grade III and IV systolic dysfunction was observed only in 7 patients (0.2%) treated with lapatinib. In phase I-III trials of pertuzumab, cardiac dysfunction was seen in 4.5-14.5% of patients with pertuzumab treatment and cardiac dysfunction was usually grade I and II. Cardiotoxicity of pertuzumab was usually reported with the trastuzumab combination and no additive cardiotoxicity was reported with addition of pertuzumab to trastuzumab. T-DM1 had a better safety profile compared to trastuzumab, no significant cardiotoxicity was observed with T-DM1 in heavily pre-treated patients. In the EMILIA study, only in 1.7% of patients in the T

  12. Adoptive transfer of autologous, HER2-specific, cytotoxic T lymphocytes for the treatment of HER2-overexpressing breast cancer.

    PubMed

    Bernhard, Helga; Neudorfer, Julia; Gebhard, Kerstin; Conrad, Heinke; Hermann, Christine; Nährig, Jörg; Fend, Falko; Weber, Wolfgang; Busch, Dirk H; Peschel, Christian

    2008-02-01

    The human epidermal growth factor receptor 2 (HER2) has been targeted as a breast cancer-associated antigen by immunotherapeutical approaches based on HER2-directed monoclonal antibodies and cancer vaccines. We describe the adoptive transfer of autologous HER2-specific T-lymphocyte clones to a patient with metastatic HER2-overexpressing breast cancer. The HLA/multimer-based monitoring of the transferred T lymphocytes revealed that the T cells rapidly disappeared from the peripheral blood. The imaging studies indicated that the T cells accumulated in the bone marrow (BM) and migrated to the liver, but were unable to penetrate into the solid metastases. The disseminated tumor cells in the BM disappeared after the completion of adoptive T-cell therapy. This study suggests the therapeutic potential for HER2-specific T cells for eliminating disseminated HER2-positive tumor cells and proposes the combination of T cell-based therapies with strategies targeting the tumor stroma to improve T-cell infiltration into solid tumors.

  13. The anti-malarial chloroquine overcomes primary resistance and restores sensitivity to trastuzumab in HER2-positive breast cancer.

    PubMed

    Cufí, Sílvia; Vazquez-Martin, Alejandro; Oliveras-Ferraros, Cristina; Corominas-Faja, Bruna; Cuyàs, Elisabet; López-Bonet, Eugeni; Martin-Castillo, Begoña; Joven, Jorge; Menendez, Javier A

    2013-01-01

    Autophagy may control the de novo refractoriness of HER2 gene-amplified breast carcinomas to the monoclonal antibody trastuzumab (Herceptin). Tumor cells originally obtained from a patient who rapidly progressed on trastuzumab ab initio display increased cellular levels of the LC3-II protein--a finding that correlates with increased numbers of autophagosomes--and decreased levels of the autophagy receptor p62/SQSTM1, a protein selectively degraded by autophagy. Trastuzumab-refractory cells are in a state of "autophagy addiction" because genetic ablation of autophagy-specific genes (ATG8, ATG5, ATG12) notably reduces intrinsic refractoriness to trastuzumab. When the anti-malarial lysosomotropic drug chloroquine impedes autophagic resolution of the accumulation of autophagolysosomes formed in the presence of trastuzumab, cells commit to die by apoptosis. Accordingly, combination treatment with trastuzumab and chloroquine radically suppresses tumor growth by > 90% in a tumor xenograft completely refractory to trastuzumab. Adding chloroquine to trastuzumab-based regimens may therefore improve outcomes among women with autophagy-addicted HER2-positive breast cancer.

  14. Anti-HER2 immunoliposomes for selective delivery of electron paramagnetic resonance imaging probes to HER2-overexpressing breast tumor cells

    PubMed Central

    Burks, Scott R.; Macedo, Luciana F.; Barth, Eugene D.; Tkaczuk, Katherine H.; Martin, Stuart S.; Rosen, Gerald M.; Halpern, Howard J.; Brodie, Angela M.

    2014-01-01

    Electron paramagnetic resonance (EPR) imaging is an emerging modality that can detect and localize paramagnetic molecular probes (so-called spin probes) in vivo. We previously demonstrated that nitroxide spin probes can be encapsulated in liposomes at concentrations exceeding 100 mM, at which nitroxides exhibit a concentration-dependent quenching of their EPR signal that is analogous to the self-quenching of fluorescent molecules. Therefore, intact liposomes encapsulating high concentrations of nitroxides exhibit greatly attenuated EPR spectral signals, and endocytosis of such liposomes represents a cell-activated contrast-generating mechanism. After endocytosis, the encapsulated nitroxide is liberated and becomes greatly diluted in the intracellular milieu. This dequenches the nitroxides to generate a robust intracellular EPR signal. It is therefore possible to deliver a high concentration of nitroxides to cells while minimizing background signal from unendocytosed liposomes. We report here that intracellular EPR signal can be selectively generated in a specific cell type by exploiting its expression of Human Epidermal Growth Factor Receptor 2 (HER2). When targeted by anti-HER2 immunoliposomes encapsulating quenched nitroxides, Hc7 cells, which are novel HER2-overexpressing cells derived from the MCF7 breast tumor cell line, endocytose the liposomes copiously, in contrast to the parent MCF7 cells or control CV1 cells, which do not express HER2. HER2-dependent liposomal delivery enables Hc7 cells to accumulate 750 μM nitroxide intracellularly. Through the use of phantom models, we verify that this concentration of nitroxides is more than sufficient for EPR imaging, thus laying the foundation for using EPR imaging to visualize HER2-overexpressing Hc7 tumors in animals. PMID:20066490

  15. HER2-positive breast cancer, how far away from the cure?-on the current situation of anti-HER2 therapy in breast cancer treatment and survival of patients.

    PubMed

    Liao, Ning

    2016-06-01

    With the diagnosis and treatment of tumor enter into the area of precision medical, based on selected targeted molecular typing of patients with individualized diagnosis and treatment play an important role. HER gene encoded epidermal growth factor receptor 2 (HER2) leading to increased early distant metastasis of breast cancer in patients and poor prognosis. However, a number of clinical studies provided evidence-based anti-HER2 targeted therapy and confirmed the benefit of anti-HER2 targeted therapy in patient survival. In recent years, through the tireless efforts of scholars in the field of breast cancer in our country, the whole diagnosis and treatment of breast cancer has accomplished an international standard. But based on a variety of factors, the anti-HER2 targeted therapy between China and the developed countries, and between different areas in China still exists certain gaps, is now a problem need to be solved. This article will analyzing the diagnostic and treatment on HER2-positive breast cancer in the United States and China, exploring reasons and looking for answers to narrow down the gap in the treatment of HER2-positive breast cancer between China and the United States. Improve the anti-HER2 targeted therapy in our country, let the patients get maximum benefit from anti-HER2 targeted therapy.

  16. Mechanisms of disease: understanding resistance to HER2-targeted therapy in human breast cancer.

    PubMed

    Nahta, Rita; Yu, Dihua; Hung, Mien-Chie; Hortobagyi, Gabriel N; Esteva, Francisco J

    2006-05-01

    Trastuzumab is a monoclonal antibody targeted against the human epidermal growth factor receptor (HER) 2 tyrosine kinase receptor, which is overexpressed in approximately 25% of invasive breast cancers. The majority of patients with metastatic breast cancer who initially respond to trastuzumab, however, demonstrate disease progression within 1 year of treatment initiation. Preclinical studies have indicated several molecular mechanisms that could contribute to the development of trastuzumab resistance. Increased signaling via the phosphatidylinositol 3-kinase/Akt pathway could contribute to trastuzumab resistance because of activation of multiple receptor pathways that include HER2-related receptors or non-HER receptors such as the insulin-like growth factor 1 receptor, which appears to be involved in a cross-talk with HER2 in resistant cells. Additionally, loss of function of the tumor suppressor PTEN gene, the negative regulator of Akt, results in heightened Akt signaling that leads to decreased sensitivity to trastuzumab. Decreased interaction between trastuzumab and its target receptor HER2, which is due to steric hindrance of HER2 by cell surface proteins such as mucin-4 (MUC4), may block the inhibitory actions of trastuzumab. Novel therapies targeted against these aberrant molecular pathways offer hope that the effectiveness and duration of response to trastuzumab can be greatly improved.

  17. A combination of two antibodies recognizing non-overlapping epitopes of HER2 induces kinase activity-dependent internalization of HER2.

    PubMed

    Szymanska, Monika; Fosdahl, Anne M; Nikolaysen, Filip; Pedersen, Mikkel W; Grandal, Michael M; Stang, Espen; Bertelsen, Vibeke

    2016-10-01

    The human epidermal growth factor receptor 2 (HER2/ErbB2) is overexpressed in a number of human cancers. HER2 is the preferred heterodimerization partner for other epidermal growth factor receptor (EGFR) family members and is considered to be resistant to endocytic down-regulation, properties which both contribute to the high oncogenic potential of HER2. Antibodies targeting members of the EGFR family are powerful tools in cancer treatment and can function by blocking ligand binding, preventing receptor dimerization, inhibiting receptor activation and/or inducing receptor internalization and degradation. With respect to antibody-induced endocytosis of HER2, various results are reported, and the effect seems to depend on the HER2 expression level and whether antibodies are given as individual antibodies or as mixtures of two or more. In this study, the effect of a mixture of two monoclonal antibodies against non-overlapping epitopes of HER2 was investigated with respect to localization and stability of HER2. Individual antibodies had limited effect, but the combination of antibodies induced internalization and degradation of HER2 by multiple endocytic pathways. In addition, HER2 was phosphorylated and ubiquitinated upon incubation with the antibody combination, and the HER2 kinase activity was found to be instrumental in antibody-induced HER2 down-regulation. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  18. [False positive of DUPAN-2 caused by IgM-human anti mouse antibody].

    PubMed

    Abe, Masaki; Hyoki, Miyuki; Abe, Ikurou; Kaito, Ken; Takagi, Ichirou

    2012-11-01

    We investigated a case in our experience presenting false-positive for DUPAN-2 by IgM-human anti mouse antibody (HAMA). A female aged 40s has been treated in our hospital from 2003. Her serum level of DUPAN-2 in 2005 and 2006 were 110 U/mL and 140 U/mL respectively. While this level was increased to 770 U/ml in 2007, and kept in the higher level so far. Around years of 2007, no meaning changes was detected by radiological and laboratory tests, and there was no significant change in her clinical signs and symptoms and medications. The elevation of DUPAN-2 was thought as a false-positive phenomenon and the mechanism was investigated. As results, no dilution lineality was found, and absorption test showed a 95% reduction of DUPAN-2 levels not by IgG and IgA, but IgM-specific antiserum. Dithiothreitoldeacylation test with neuraminidase, and absorption test with HBR-1, IIR, and mouse IgM serum, it was suggested that the IgM with HAMA activity of the patient reacted with mouse monoclonal antibodies in reagents. Moreover, the HPLC-eluted fraction of DUPAN-2 of this patients was detected in the fraction of IgM, which as different from that of a control pancreatic cancer patient. Above these data, elevation of DUPAN-2 in this patient was a false positive phenomenon by IgM-HAMA reacting with mouse monoclonal antibodies in reagents. Although there are few reported cases of false positive phenomenon in DUPAN-2 measurement, we have to pay attention to such phenomenon when detecting an unlikely higher levels that could not be explained by clinical information.

  19. Human Anti-Plague Monoclonal Antibodies Protect Mice from Yersinia pestis in a Bubonic Plague Model

    PubMed Central

    Xiao, Xiaodong; Zhu, Zhongyu; Dankmeyer, Jennifer L.; Wormald, Michael M.; Fast, Randy L.; Worsham, Patricia L.; Cote, Christopher K.; Amemiya, Kei; Dimitrov, Dimiter S.

    2010-01-01

    Yersinia pestis is the etiologic agent of plague that has killed more than 200 million people throughout the recorded history of mankind. Antibiotics may provide little immediate relief to patients who have a high bacteremia or to patients infected with an antibiotic resistant strain of plague. Two virulent factors of Y. pestis are the capsid F1 protein and the low-calcium response (Lcr) V-protein or V-antigen that have been proven to be the targets for both active and passive immunization. There are mouse monoclonal antibodies (mAbs) against the F1- and V-antigens that can passively protect mice in a murine model of plague; however, there are no anti-Yersinia pestis monoclonal antibodies available for prophylactic or therapeutic treatment in humans. We identified one anti-F1-specific human mAb (m252) and two anti-V-specific human mAb (m253, m254) by panning a naïve phage-displayed Fab library against the F1- and V-antigens. The Fabs were converted to IgG1s and their binding and protective activities were evaluated. M252 bound weakly to peptides located at the F1 N-terminus where a protective mouse anti-F1 mAb also binds. M253 bound strongly to a V-antigen peptide indicating a linear epitope; m254 did not bind to any peptide from a panel of 53 peptides suggesting that its epitope may be conformational. M252 showed better protection than m253 and m254 against a Y, pestis challenge in a plague mouse model. A synergistic effect was observed when the three antibodies were combined. Incomplete to complete protection was achieved when m252 was given at different times post-challenge. These antibodies can be further studied to determine their potential as therapeutics or prophylactics in Y. pestis infection in humans. PMID:20976274

  20. Human anti-plague monoclonal antibodies protect mice from Yersinia pestis in a bubonic plague model.

    PubMed

    Xiao, Xiaodong; Zhu, Zhongyu; Dankmeyer, Jennifer L; Wormald, Michael M; Fast, Randy L; Worsham, Patricia L; Cote, Christopher K; Amemiya, Kei; Dimitrov, Dimiter S

    2010-10-13

    Yersinia pestis is the etiologic agent of plague that has killed more than 200 million people throughout the recorded history of mankind. Antibiotics may provide little immediate relief to patients who have a high bacteremia or to patients infected with an antibiotic resistant strain of plague. Two virulent factors of Y. pestis are the capsid F1 protein and the low-calcium response (Lcr) V-protein or V-antigen that have been proven to be the targets for both active and passive immunization. There are mouse monoclonal antibodies (mAbs) against the F1- and V-antigens that can passively protect mice in a murine model of plague; however, there are no anti-Yersinia pestis monoclonal antibodies available for prophylactic or therapeutic treatment in humans. We identified one anti-F1-specific human mAb (m252) and two anti-V-specific human mAb (m253, m254) by panning a naïve phage-displayed Fab library against the F1- and V-antigens. The Fabs were converted to IgG1s and their binding and protective activities were evaluated. M252 bound weakly to peptides located at the F1 N-terminus where a protective mouse anti-F1 mAb also binds. M253 bound strongly to a V-antigen peptide indicating a linear epitope; m254 did not bind to any peptide from a panel of 53 peptides suggesting that its epitope may be conformational. M252 showed better protection than m253 and m254 against a Y, pestis challenge in a plague mouse model. A synergistic effect was observed when the three antibodies were combined. Incomplete to complete protection was achieved when m252 was given at different times post-challenge. These antibodies can be further studied to determine their potential as therapeutics or prophylactics in Y. pestis infection in humans.

  1. The anti-malarial chloroquine overcomes Primary resistance and restores sensitivity to Trastuzumab in HER2-positive breast cancer

    PubMed Central

    Cufí, Sílvia; Vazquez-Martin, Alejandro; Oliveras-Ferraros, Cristina; Corominas-Faja, Bruna; Cuyàs, Elisabet; López-Bonet, Eugeni; Martin-Castillo, Begoña; Joven, Jorge; Menendez, Javier A.

    2013-01-01

    Autophagy may control the de novo refractoriness of HER2 gene-amplified breast carcinomas to the monoclonal antibody trastuzumab (Herceptin). Tumor cells originally obtained from a patient who rapidly progressed on trastuzumab ab initio display increased cellular levels of the LC3-II protein—a finding that correlates with increased numbers of autophagosomes—and decreased levels of the autophagy receptor p62/SQSTM1, a protein selectively degraded by autophagy. Trastuzumab-refractory cells are in a state of “autophagy addiction” because genetic ablation of autophagy-specific genes (ATG8, ATG5, ATG12) notably reduces intrinsic refractoriness to trastuzumab. When the anti-malarial lysosomotropic drug chloroquine impedes autophagic resolution of the accumulation of autophagolysosomes formed in the presence of trastuzumab, cells commit to die by apoptosis. Accordingly, combination treatment with trastuzumab and chloroquine radically suppresses tumor growth by > 90% in a tumor xenograft completely refractory to trastuzumab. Adding chloroquine to trastuzumab-based regimens may therefore improve outcomes among women with autophagy-addicted HER2-positive breast cancer. PMID:23965851

  2. Adjuvant Anti-HER2 Therapy, Treatment-Related Amenorrhea, and Survival in Premenopausal HER2-Positive Early Breast Cancer Patients.

    PubMed

    Lambertini, Matteo; Campbell, Christine; Bines, José; Korde, Larissa A; Izquierdo, Miguel; Fumagalli, Debora; Del Mastro, Lucia; Ignatiadis, Michail; Pritchard, Kathleen; Wolff, Antonio C; Jackisch, Christian; Lang, Istvan; Untch, Michael; Smith, Ian; Boyle, Frances; Xu, Binghe; Barrios, Carlos H; Baselga, José; Moreno-Aspitia, Alvaro; Piccart, Martine; Gelber, Richard D; de Azambuja, Evandro

    2018-06-05

    In premenopausal patients with human epidermal growth factor receptor 2 (HER2)-positive early breast cancer, the gonadotoxicity of trastuzumab and lapatinib remains largely uncertain, and the prognostic effect of treatment-related amenorrhea (TRA) is unknown. In the Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization (BIG 2-06) phase III trial, HER2-positive early breast cancer patients were randomized (1:1:1:1) to receive one year of trastuzumab, lapatinib, their sequence, or their combination. As per study protocol, menopausal status was collected in all patients at random assignment and at week 37 visit. We investigated TRA rates and whether TRA in patients with hormone receptor-positive and -negative tumors would impact disease-free survival (DFS) and overall survival (OS). Landmark and time-dependent modeling were used to account for guarantee-time bias. All statistical tests were two-sided. A total of 2862 premenopausal women were included, of whom 1679 (58.7%) had hormone receptor-positive disease. Median age was 43 (interquartile range = 38-47) years. Similar TRA rates were observed in the trastuzumab (72.6%), lapatinib (74.0%), trastuzumab→lapatinib (72.1%), and trastuzumab+lapatinib (74.8%) arms (P = .64). The association between TRA and survival outcomes differed according to hormone-receptor status (Pinteraction for DFS = .007; Pinteraction for OS = .003). For hormone receptor-positive patients, the TRA cohort had statistically significantly better DFS (adjusted hazard ratio [aHR] = 0.58, 95% confidence interval [CI] = 0.45 to 0.76) and OS (aHR = 0.63, 95% CI = 0.40 to 0.99) than the no TRA cohort. No difference was observed in hormone receptor-negative patients. In this unplanned analysis, no association between TRA rate and type of anti-HER2 treatment was observed. TRA was associated with statistically significant survival benefits in premenopausal hormone receptor-positive/HER2-positive early breast cancer patients.

  3. In vitro and in vivo studies of the combination of IGF1R inhibitor figitumumab (CP-751,871) with HER2 inhibitors trastuzumab and neratinib.

    PubMed

    Chakraborty, Ashok K; Zerillo, Cynthia; DiGiovanna, Michael P

    2015-08-01

    The insulin-like growth factor I receptor (IGF1R) has been linked to resistance to HER2-directed therapy with trastuzumab (Herceptin). We examined the anti-tumor activity of figitumumab (CP-751,871), a human monoclonal antibody that blocks IGF1R ligand binding, alone and in combination with the therapeutic anti-HER2 antibody trastuzumab and the pan-HER family tyrosine kinase inhibitor neratinib, using in vitro and in vivo breast cancer model systems. In vitro assays of proliferation, apoptosis, and signaling, and in vivo anti-tumor experiments were conducted in HER2-overexpressing (BT474) and HER2-normal (MCF7) models. We find single-agent activity of the HER2-targeting drugs but not figitumumab in the BT474 model, while the reverse is true in the MCF7 model. However, in both models, combining figitumumab with HER2-targeting drugs shows synergistic anti-proliferative and apoptosis-inducing effects, and optimum inhibition of downstream signaling. In murine xenograft models, synergistic anti-tumor effects were observed in the HER2-normal MCF7 model for the combination of figitumumab with trastuzumab, and, in the HER2-overexpressing BT474 model, enhanced anti-tumor effects were observed for the combination of figitumumab with either trastuzumab or neratinib. Analysis of tumor extracts from the in vivo experiments showed evidence of the most optimal inhibition of downstream signaling for the drug combinations over the single-agent therapies. These results suggest promise for such combinations in treating patients with breast cancer, and that, unlike the case for single-agent therapy, the therapeutic effects of such combinations may be independent of expression levels of the individual receptors or the single-agent activity profile.

  4. ER and HER2 expression are positively correlated in HER2 non-overexpressing breast cancer.

    PubMed

    Pinhel, Isabel; Hills, Margaret; Drury, Suzanne; Salter, Janine; Sumo, Georges; A'Hern, Roger; Bliss, Judith M; Sestak, Ivana; Cuzick, Jack; Barrett-Lee, Peter; Harris, Adrian; Dowsett, Mitch

    2012-03-14

    Estrogen receptor-α (ER) and human epidermal growth factor receptor 2 (HER2) positivity are inversely correlated by standard criteria. However, we investigated the quantitative relation between ER and HER2 expression at both RNA and protein levels in HER2+ve and HER2-ve breast carcinomas. ER and HER2 levels were assessed with immunohistochemistry (IHC) and (for HER2) fluorescent in situ hybridization (FISH) and by quantitative reverse transcription-polymerase chain reaction (q-RT-PCR) in formalin-fixed primary breast cancers from 448 patients in the National Cancer Research Institute (NCRI) Adjuvant Breast Cancer Trial (ABC) tamoxifen-only arm. Relations at the RNA level were assessed in 1,139 TransATAC tumors. ER and HER2 RNA levels were negatively correlated as expected in HER2+ve (IHC 3+ and/or FISH-amplified) tumors (r = -0.45; P = 0.0028). However, in HER2-ve tumors (ER+ve and ER-ve combined), a significant positive correlation was found (r = 0.43; P < 0.0001), HER2 RNA levels being 1.74-fold higher in ER+ve versus ER-ve tumors. This correlation was maintained in the ER+veHER2-ve subgroup (r = 0.24; P = 0.0023) and confirmed in this subgroup in 1,139 TransATAC tumours (r = 0.25; P < 0.0001). The positive relation extended to IHC-detected ER in ABC: mean ± 95% confidence interval (CI) H-scores were 90 ± 19 and 134 ± 19 for 0 and 1+ HER2 IHC categories, respectively (P = 0.0013). A trend toward lower relapse-free survival (RFS) was observed in patients with the lowest levels of ER and HER2 RNA levels within the ER+veHER2-ve subgroup both for ABC and TransATAC cohorts. ER and HER2 expression is positively correlated in HER2-ve tumors. The distinction between HER2+ve and HER2-ve is greater in ER-ve than in ER+ve tumors. These findings are important to consider in clinical trials of anti-HER2 and anti-endocrine therapy in HER2-ve disease. Clinical trial identifier: ISRCTN31514446.

  5. Antitumor activity of pan-HER inhibitors in HER2-positive gastric cancer.

    PubMed

    Yoshioka, Takahiro; Shien, Kazuhiko; Namba, Kei; Torigoe, Hidejiro; Sato, Hiroki; Tomida, Shuta; Yamamoto, Hiromasa; Asano, Hiroaki; Soh, Junichi; Tsukuda, Kazunori; Nagasaka, Takeshi; Fujiwara, Toshiyoshi; Toyooka, Shinichi

    2018-04-01

    Molecularly targeted therapy has enabled outstanding advances in cancer treatment. Whereas various anti-human epidermal growth factor receptor 2 (HER2) drugs have been developed, trastuzumab is still the only anti-HER2 drug presently available for gastric cancer. In this study, we propose novel treatment options for patients with HER2-positive gastric cancer. First, we determined the molecular profiles of 12 gastric cancer cell lines, and examined the antitumor effect of the pan-HER inhibitors afatinib and neratinib in those cell lines. Additionally, we analyzed HER2 alteration in 123 primary gastric cancers resected from Japanese patients to clarify possible candidates with the potential to respond to these drugs. In the drug sensitivity analysis, both afatinib and neratinib produced an antitumor effect in most of the HER2-amplified cell lines. However, some cells were not sensitive to the drugs. When the molecular profiles of the cells were compared based on the drug sensitivities, we found that cancer cells with lower mRNA expression levels of IGFBP7, a tumor suppressor gene that inhibits the activation of insulin-like growth factor-1 receptor (IGF-1R), were less sensitive to pan-HER inhibitors. A combination therapy consisting of pan-HER inhibitors and an IGF-1R inhibitor, picropodophyllin, showed a notable synergistic effect. Among 123 clinical samples, we found 19 cases of HER2 amplification and three cases of oncogenic mutations. In conclusion, afatinib and neratinib are promising therapeutic options for the treatment of HER2-amplified gastric cancer. In addition to HER2 amplification, IGFBP7 might be a biomarker of sensitivity to these drugs, and IGF-1R-targeting therapy can overcome drug insensitiveness in HER2-amplified gastric cancer. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  6. Dual blockade of HER2 in HER2-overexpressing tumor cells does not completely eliminate HER3 function.

    PubMed

    Garrett, Joan T; Sutton, Cammie R; Kuba, María Gabriela; Cook, Rebecca S; Arteaga, Carlos L

    2013-02-01

    Dual blockade of HER2 with trastuzumab and lapatinib or with pertuzumab is a superior treatment approach compared with single-agent HER2 inhibitors. However, many HER2-overexpressing breast cancers still escape from this combinatorial approach. Inhibition of HER2 and downstream phosphoinositide 3-kinase (PI3K)/AKT causes a transcriptional and posttranslational upregulation of HER3 which, in turn, counteracts the antitumor action of the HER2-directed therapies. We hypothesized that suppression of HER3 would synergize with dual blockade of HER2 in breast cancer cells sensitive and refractory to HER2 antagonists. Inhibition of HER2/HER3 in HER2(+) breast cancer cell lines was evaluated by Western blotting. We analyzed drug-induced apoptosis and two- and three-dimensional growth in vitro. Growth inhibition of PI3K was examined in vivo in xenografts treated with combinations of trastuzumab, lapatinib, and the HER3-neutralizing monoclonal antibody U3-1287. Treatment with U3-1287 blocked the upregulation of total and phosphorylated HER3 that followed treatment with lapatinib and trastuzumab and, in turn, enhanced the antitumor action of the combination against trastuzumab-sensitive and -resistant cells. Mice bearing HER2(+) xenografts treated with lapatinib, trastuzumab, and U3-1287 exhibited fewer recurrences and better survival than mice treated with lapatinib and trastuzumab. Dual blockade of HER2 with trastuzumab and lapatinib does not eliminate the compensatory upregulation of HER3. Therapeutic inhibitors of HER3 should be considered as part of multidrug combinations aimed at completely and rapidly disabling the HER2 network in HER2-overexpressing breast cancers.

  7. Effects of passage number on growth and productivity of hybridoma secreting MRSA anti-PBP2a monoclonal antibodies.

    PubMed

    Corrêa, Arthur Luiz; Senna, José Procópio Moreno; de Sousa, Álvaro Paiva Braga

    2016-05-01

    Monoclonal antibodies (mAb) are high added value glycoproteins recommended for immunotherapy, diagnosis, and also for the treatment of bacterial infections resistant to multiple drugs such as Methicillin Resistant Staphylococcus aureus (MRSA). In addition to environmental conditions related to cell cultures, the intrinsic characteristics of hybridoma cells, like the secretion stability of monoclonal antibodies by the cells through successive subcultures, are relevant for the characterization of cell lines related to the productivity of mAb. The rate of mAb production differs significantly between different cell lines and different passage numbers, and it is an important variable in characterization of cell lines. In order to find a more robust, faster-growing, and higher-productivity cell line of hybridoma, cultivations in 24-well plates were performed in different subculture periods, or cell passages (P), of hybridoma cells producing MRSA anti-PBP2a monoclonal antibodies [MRSA-antiPBP2a (mAb)]. The objective of this study was to study the effects of cell growth and production of MRSA-antiPBP2a mAb secreted by murine hybridoma cells grown in different passages as well as determine the which passages the hybridomas can be cultivated without harming their growth and productivity. So, cell growth profiles of hybridomas secreting MRSA-antiPBP2a (mAb) and the production of MRSA-antiPBP2a mAb in different subculture periods or cell passages (P) were studied. Cell growth tests, monoclonal antibody productivity, and metabolite characteristics revealed substantial differences in those cells kept between P10 and P50. Similarities in the secretion of monoclonal antibody, growth, and metabolic profiles, were noted in the MRSA-antiPBP2a mAb producing hybridoma cells kept between P10 and P20. Also, glucose consumption (g/L) and lactate production (g/L) in the latter cell cultures were monitored daily through biochemical analyzer. As of P30, it was observed a 4.4 times reduction

  8. The combination of anti-KIR monoclonal antibodies with anti-PD-1/PD-L1 monoclonal antibodies could be a critical breakthrough in overcoming tumor immune escape in NSCLC.

    PubMed

    He, Yayi; Liu, Sangtian; Mattei, Jane; Bunn, Paul A; Zhou, Caicun; Chan, Daniel

    2018-01-01

    The anti-programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) monoclonal antibody has a good effect in the treatment of non-small cell lung cancer (NSCLC), but not all PD-1/PD-L1 positive patients can get benefit from it. Compensatory expression of other immune checkpoints may be correlated with the poor efficacy of anti-PD-1/PD-L1 monoclonal antibodies. The inhibitory human leukocyte antigen (HLA)/killer cell Ig-like receptor (KIR) can effectively block the killing effect of natural killer (NK) cells on tumors. Our previous studies have confirmed that high expression of KIR was correlated with poor prognosis of NSCLC. Inhibitory KIR expression was positively correlated with the expression of PD-1. The expressions of KIR 2D (L1, L3, L4, S4) (BC032422/ADQ31987/NP_002246/NP_036446, Abcam) and PD-1 (NAT 105, Cell marque) proteins was assessed by immunohistochemistry. The expression of inhibitory KIR in tumor cells or tumor infiltrating lymphocytes (TILs) is associated with PD-1 expression. Among PD-1 positive patients, 76.3% were KIR 2D (L1, L3, L4, S4) positive on tumor cells, and 74.6% were KIR 2D (L1, L3, L4, S4) positive on TILs. We compared the expression of inhibitory KIR before and after treatment with nivolumab in 11 patients with NSCLC. We found that five (45.5%) patients had positive expression of inhibitory KIR in tumor tissue after being treated with anti-PD-1 monoclonal antibodies, two of whom exhibited a significant increase in expression of inhibitory KIR, and three showed no change. PD-1 expression was correlated with KIR 2D (L1, L3, L4, S4) on tumor cells or TILs. The resistance to anti-PD-1 monoclonal antibody treatment might be related to KIR. The inhibitory HLA/KIR could combine with the PD-1/PD-L1 signaling pathway negatively regulating NSCLC tumor immunity.

  9. In vivo examination of (188)Re(I)-tricarbonyl-labeled trastuzumab to target HER2-overexpressing breast cancer.

    PubMed

    Chen, Kuo-Ting; Lee, Te-Wei; Lo, Jem-Mau

    2009-05-01

    Trastuzumab (Herceptin), a humanized IgG1 monoclonal antibody directed against the extracellular domain of the HER2 protein, acts as an immunotherapeutic agent for HER2-overexpressing human breast cancers. Radiolabeled trastuzumab with beta- or alpha emitters can be used as radioimmunotherapeutic agent for the similar purpose but with additional radiation effect. In this study, trastuzumab was labeled with (188)Re for radioimmunotherapy of HER2/neu-positive breast cancer. (188)Re(I)-tricarbonyl ion, [(188)Re(OH(2))(3)(CO)(3)](+), was employed as a precursor for directly labeling the monoclonal antibody with (188)Re. The immunoreactivity of (188)Re(I)-trastuzumab was estimated by competition receptor-binding assay using HER2/neu-overexpressive BT-474 human breast cancer cells. The localization properties of (188)Re(I)-trastuzumab within both tumor and normal tissues of athymic mice bearing BT-474 human breast cancer xenografts (HER2/neu-overexpressive) and similar mice bearing MCF-7 human breast cancer xenografts (HER2/neu-low expressive) were investigated. When incubated with human serum albumin and histidine at 25 degrees C, (188)Re(I)-trastuzumab was found to be stable within 24 h. The IC(50) of (188)Re(I)-trastuzumab was found to be 22.63+/-4.57 nM. (188)Re(I)-trastuzumab was shown to accumulate specifically in BT-474 tumor tissue in in vivo biodistribution studies. By microSPECT/CT, the image of (188)Re localized BT-474 tumor was clearly visualized within 24 h. In contrast, (188)Re(I)-trastuzumab uptake in HER2-low-expressing MCF-7 tumor was minimal, and the (188)Re image at the localization of the tumor was dim. These results reveal that (188)Re(I)-trastuzumab could be an appropriate radioimmunotherapeutic agent for the treatment of HER2/neu-overexpressing cancers.

  10. First human study of a chimeric anti-methamphetamine monoclonal antibody in healthy volunteers.

    PubMed

    Stevens, Misty W; Henry, Ralph L; Owens, S Michael; Schutz, Ralph; Gentry, W Brooks

    2014-01-01

    This first-in-human study examined the safety and pharmacokinetics of ch-mAb7F9, an anti-methamphetamine monoclonal antibody, in healthy volunteers. Single, escalating doses of ch-mAb7F9 over the range of 0.2 to 20 mg/kg were administered to 42 subjects who were followed for 147 d. Safety was measured by physical examinations, adverse events, vital signs, electrocardiograms, and clinical laboratory testing. Serum ch-mAb7F9 concentration and immunogenicity analyses were performed. There were no serious adverse reactions or discontinuations from the study due to adverse events. No trends emerged in the frequency, relatedness, or severity of adverse events with increased dose or between active and placebo treated subjects. Ch-mAb7F9 displayed expected IgG pharmacokinetic parameters, including a half-life of 17-19 d in the 3 highest dose groups and volume of distribution of 5-6 L, suggesting the antibody is confined primarily to the vascular compartment. Four (12.5%) of the 32 subjects receiving ch-mAb7F9 were confirmed to have developed a human anti-chimeric antibody response by the end of the study; however, this response did not appear to be dose related. Overall, no apparent safety or tolerability concerns were identified; a maximum tolerated dose was not reached in this Phase 1 study. Ch-mAb7F9 therefore appears safe for human administration.

  11. Dual-colour HER2/chromosome 17 chromogenic in situ hybridisation enables accurate assessment of HER2 genomic status in ovarian tumours.

    PubMed

    Yan, Benedict; Choo, Shoa Nian; Mulyadi, Patricia; Srivastava, Supriya; Ong, Chee Wee; Yong, Kol Jia; Putti, Thomas; Salto-Tellez, Manuel; Lim, Gkeok Stzuan Diana

    2011-12-01

    Ovarian cancer is a leading cause of gynaecological cancer-related morbidity and mortality. There has been increasing interest in the potential utility of anti-human epidermal growth factor receptor 2 (anti-HER2) agents in the treatment of this disease, with the attendant need to identify suitable predictive biomarkers of response to treatment. The authors studied the prevalence of HER2 genomic amplification and overexpression in 85 ovarian tumours in the local patient cohort of this study, as well as the concordance rate between immunohistochemistry, fluorescent in situ hybridisation (FISH) and a dual-colour HER2/chromosome 17 centromere chromogenic in situ hybridisation (CISH) assay. The authors identified HER2 genomic amplification and protein overexpression in 35.3% (6/17) and 29.4% (5/17), respectively, of primary ovarian mucinous carcinomas. No other cancer subtypes displayed HER2 amplification or protein overexpression. The authors also found a perfect concordance between FISH and dual-colour CISH analysis (κ coefficient 1.0, p<0.001). The results of this study support existing reports that HER2 genomic amplification and protein overexpression are predominantly found in primary ovarian mucinous carcinomas. Given the perfect concordance between the FISH and dual-colour CISH assays and the advantages of CISH over FISH analysis, future clinical trials investigating the use of anti-HER2 therapeutics in ovarian carcinomas should incorporate dual-colour CISH as part of the HER2 status assessment algorithm.

  12. Tyrosine kinase inhibitors for brain metastases in HER2-positive breast cancer.

    PubMed

    Duchnowska, Renata; Loibl, Sibylle; Jassem, Jacek

    2018-06-01

    Approximately 30-50% of advanced HER2-positive breast cancer patients will develop central nervous system (CNS) metastases, with an annual risk of around 10%, and a half of them will die from brain progression. An increased risk of brain metastases is also seen in patients with early HER2-positive breast cancer administered curative therapy. Brain metastases in HER2-positive breast cancer patients usually constitute the first site of recurrence. The administration of anti-HER2 monoclonal antibodies, trastuzumab and pertuzumab, considerably delays the onset of symptomatic brain disease: however, the limited penetration of these compounds into the CNS hinders their efficacy. The small-molecule tyrosine kinase inhibitors of epidermal growth factor receptors family have established activity in HER2-positive breast cancer in both advanced disease and neoadjuvant setting. Favorable physico-chemical properties of these compounds allow them for a more efficient penetration through the blood-brain barrier, and hold the promise for more effective prevention and treatment of brain metastases. In this article we review the role of currently available or investigational HER2 tyrosine kinase inhibitors: lapatinib, neratinib, afatinib and tucatinib in the treatment of brain metastases in HER2-positive breast cancer patients. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Characterization of a recombinant humanized anti-cocaine monoclonal antibody and its Fab fragment.

    PubMed

    Kirley, Terence L; Norman, Andrew B

    2015-01-01

    Variations of post-translational modifications are important for stability and in vivo behavior of therapeutic antibodies. A recombinant humanized anti-cocaine monoclonal antibody (h2E2) was characterized for heterogeneity of N-linked glycosylation and disulfide bonds. In addition, charge heterogeneity, which is partially due to the presence or absence of C-terminal lysine on the heavy chains, was examined. For cocaine overdose therapy, Fab fragments may be therapeutic, and thus, a simplified method of generation, purification, and characterization of the Fab fragment generated by Endoproteinase Lys-C digestion was devised. Both the intact h2E2 antibody and purified Fab fragments were analyzed for their affinities for cocaine and 2 of its metabolites, benzoylecgonine and cocaethylene, by fluorescence quenching of intrinsic antibody tyrosine and tryptophan fluorescence resulting from binding of these drugs. Binding constants obtained from fluorescence quenching measurements are in agreement with recently published radioligand and ELISA binding assays. The dissociation constants determined for the h2E2 monoclonal and its Fab fragment are approximately 1, 5, and 20 nM for cocaethylene, cocaine, and benzoylecgonine, respectively. Tryptophan fluorescence quenching (emission at 330 nm) was measured after either excitation of tyrosine and tryptophan (280 nm) or selective excitation of tryptophan alone (295 nm). More accurate binding constants are obtained using tryptophan selective excitation at 295 nm, likely due to interfering absorption of cocaine and metabolites at 280 nm. These quenching results are consistent with multiple tryptophan and tyrosine residues in or near the predicted binding location of cocaine in a previously published 3-D model of this antibody's variable region.

  14. Development of EMab-51, a Sensitive and Specific Anti-Epidermal Growth Factor Receptor Monoclonal Antibody in Flow Cytometry, Western Blot, and Immunohistochemistry.

    PubMed

    Itai, Shunsuke; Kaneko, Mika K; Fujii, Yuki; Yamada, Shinji; Nakamura, Takuro; Yanaka, Miyuki; Saidoh, Noriko; Handa, Saori; Chang, Yao-Wen; Suzuki, Hiroyoshi; Harada, Hiroyuki; Kato, Yukinari

    2017-10-01

    The epidermal growth factor receptor (EGFR) is a member of the human epidermal growth factor receptor (HER) family of receptor tyrosine kinases and is involved in cell growth and differentiation. EGFR homodimers or heterodimers with other HER members, such as HER2 and HER3, activate downstream signaling cascades in many cancers. In this study, we developed novel anti-EGFR monoclonal antibodies (mAbs) and characterized their efficacy in flow cytometry, Western blot, and immunohistochemical analyses. First, we expressed the full-length or ectodomain of EGFR in LN229 glioblastoma cells and then immunized mice with LN229/EGFR or ectodomain of EGFR, and performed the first screening using enzyme-linked immunosorbent assays. Subsequently, we selected mAbs according to their efficacy in flow cytometry (second screening), Western blot (third screening), and immunohistochemical (fourth screening) analyses. Among 100 mAbs, only one clone EMab-51 (IgG 1 , kappa) reacted with EGFR in Western blot analysis. Finally, immunohistochemical analyses with EMab-51 showed sensitive and specific reactions against oral cancer cells, warranting the use of EMab-51 to detect EGFR in pathological analyses of EGFR-expressing cancers.

  15. Anti-ErbB-2 mAb therapy requires type I and II interferons and synergizes with anti-PD-1 or anti-CD137 mAb therapy.

    PubMed

    Stagg, John; Loi, Sherene; Divisekera, Upulie; Ngiow, Shin Foong; Duret, Helene; Yagita, Hideo; Teng, Michele W; Smyth, Mark J

    2011-04-26

    Trastuzumab, a monoclonal antibody targeting human epidermal growth factor receptor-2 (HER2/ErbB-2), has become the mainstay of treatment for HER2-positive breast cancer. Nevertheless, its exact mechanism of action has not been fully elucidated. Although several studies suggest that Fc receptor-expressing immune cells are involved in trastuzumab therapy, the relative contribution of lymphocyte-mediated cellular cytotoxicity and antitumor cytokines remains unknown. We report here that anti-ErbB-2 mAb therapy is dependent on the release of type I and type II IFNs but is independent of perforin or FasL. Our study thus challenges the notion that classical antibody-dependent, lymphocyte-mediated cellular cytotoxicity is important for trastuzumab. We demonstrate that anti-ErbB-2 mAb therapy of experimental tumors derived from MMTV-ErbB-2 transgenic mice triggers MyD88-dependent signaling and primes IFN-γ-producing CD8+ T cells. Adoptive cell transfer of purified T cell subsets confirmed the essential role of IFN-γ-producing CD8+ T cells. Notably, anti-ErbB-2 mAb therapy was independent of IL-1R or IL-17Ra signaling. Finally, we investigated whether immunostimulatory approaches with antibodies against programmed death-1 (PD-1) or 41BB (CD137) could be used to capitalize on the immune-mediated effects of trastuzumab. We demonstrate that anti-PD-1 or anti-CD137 mAb can significantly improve the therapeutic activity of anti-ErbB-2 mAb in immunocompetent mice.

  16. A PI3K p110α-selective inhibitor enhances the efficacy of anti-HER2/neu antibody therapy against breast cancer in mice.

    PubMed

    Choi, Jae-Hyeog; Kim, Ki Hyang; Roh, Kug-Hwan; Jung, Hana; Lee, Anbok; Lee, Ji-Young; Song, Joo Yeon; Park, Seung Jae; Kim, Ilhwan; Lee, Won-Sik; Seo, Su-Kil; Choi, Il-Whan; Fu, Yang-Xin; Yea, Sung Su; Park, SaeGwang

    2018-01-01

    Combination therapies with phosphoinositide 3-kinase (PI3K) inhibitors and trastuzumab (anti-human epidermal growth factor receptor [HER]2/neu antibody) are effective against HER2+ breast cancer. Isoform-selective PI3K inhibitors elicit anti-tumor immune responses that are distinct from those induced by inhibitors of class I PI3K isoforms (pan-PI3K inhibitors). The present study investigated the therapeutic effect and potential for stimulating anti-tumor immunity of combined therapy with an anti-HER2/neu antibody and pan-PI3K inhibitor (GDC-0941) or a PI3K p110α isoform-selective inhibitor (A66) in mouse models of breast cancer. The anti-neu antibody inhibited tumor growth and enhanced anti-tumor immunity in HER2/neu+ breast cancer TUBO models, whereas GDC-0941 or A66 alone did not. Anti-neu antibody and PI3K inhibitor synergistically promoted anti-tumor immunity by increasing functional T cell production. In the presence of the anti-neu antibody, A66 was more effective than GDC-0941 at increasing the fraction of CD4 + , CD8 + , and IFN-γ + CD8 + T cells in the tumor-infiltrating lymphocyte population. Detection of IFN-γ levels by enzyme-linked immunospot assay showed that the numbers of tumor-specific T cells against neu and non-neu tumor antigens were increased by combined PI3K inhibitor plus anti-neu antibody treatment, with A66 exhibiting more potent effects than GDC-0941. In a TUBO (neu+) and TUBO-P2J (neu-) mixed tumor model representing immunohistochemistry 2+ tumors, A66 suppressed tumor growth and prolonged survival to a greater extent than GDC-0941 when combined with anti-neu antibody. These results demonstrate that a PI3K p110α-isoform-selective inhibitor is an effective adjunct to trastuzumab in the treatment of HER2-positive breast cancer.

  17. Human epidermal growth factor receptor 2 overexpression in breast cancer of patients with anti-Yo--associated paraneoplastic cerebellar degeneration.

    PubMed

    Rojas-Marcos, Iñigo; Picard, Geraldine; Chinchón, David; Gelpi, Ellen; Psimaras, Dimitri; Giometto, Bruno; Delattre, J Y; Honnorat, J; Graus, F

    2012-04-01

    Isolated case reports suggest that breast tumors from patients with paraneoplastic cerebellar degeneration (PCD) and Yo antibodies overexpress human epidermal growth factor receptor 2 (HER2). HER2 overexpression is present in 15%-25% of breast cancers and is associated with poor prognosis. We retrospectively analyzed the status of HER2 in breast tumors of 27 patients with anti-Yo-associated PCD to evaluate whether HER2 overexpression in this group of patients is higher than expected. In addition, we analyzed HER2 status of 19 breast tumors from patients with paraneoplastic neurological syndromes and Ri antibodies to see whether HER2 was specifically related to anti-Yo-associated PCD. We also assessed cdr2 expression (the onconeural antigen recognized by Yo antibodies) in 21 HER2-positive breast tumors from patients without paraneoplastic neurological syndromes. HER2 was overexpressed in 26 patients (96.3%) with anti-Yo-associated PCD but only in 2 patients (10.5%) with paraneoplastic neurological syndromes associated with Ri antibodies (P< .0001). Only 5 (23.8%) of the 21 HER2-positive breast tumors showed cdr2 immunoreactivity. This study shows a very high frequency of HER2 overexpression in breast cancers in patients with anti-Yo-associated PCD but not in those from patients with Ri antibodies. Although the expression of cdr2 onconeural antigen is not high in HER2-positive breast cancers, HER2 overexpression seems to be an important requirement to develop an anti-Yo-associated PCD.

  18. Mechanisms of resistance to anti-human epidermal growth factor receptor 2 agents in breast cancer.

    PubMed

    Mukohara, Toru

    2011-01-01

    Approximately 20% of breast cancers are characterized by overexpression of human epidermal growth factor receptor 2 (HER2) protein and associated gene amplification, and the receptor tyrosine kinase is believed to play a critical role in the pathogenesis of these tumors. The development and implementation of trastuzumab, a humanized monoclonal antibody against the extracellular domain of HER2 protein, has significantly improved treatment outcomes in patients with HER2-overexpressing breast cancer. However, despite this clinical usefulness, unmet needs for better prediction of trastuzumab's response and overcoming primary and acquired resistance remain. In this review, we discuss several potential mechanisms of resistance to trastuzumab that have been closely studied over the last decade. Briefly, these mechanisms include: impaired access of trastuzumab to HER2 by expression of extracellular domain-truncated HER2 (p95 HER2) or overexpression of MUC4; alternative signaling from insulin-like growth factor-1 receptor, other epidermal growth factor receptor family members, or MET; aberrant downstream signaling caused by loss of phosphatase and tensin homologs deleted from chromosome 10 (PTEN), PIK3CA mutation, or downregulation of p27; or FCGR3A polymorphisms. In addition, we discuss potential strategies for overcoming resistance to trastuzumab. Specifically, the epidermal growth factor receptor/HER2 tyrosine kinase inhibitor lapatinib partially overcame trastuzumab resistance in a clinical setting, so its efficacy results and limited data regarding potential mechanisms of resistance to the drug are also discussed. © 2010 Japanese Cancer Association.

  19. Establishment of two new cell lines derived from human breast carcinomas with HER-2/neu amplification.

    PubMed Central

    Meltzer, P.; Leibovitz, A.; Dalton, W.; Villar, H.; Kute, T.; Davis, J.; Nagle, R.; Trent, J.

    1991-01-01

    Two human cell lines (UACC-812 and 893), both containing significant amplification of the HER-2/neu gene, were established from biopsy specimens of breast carcinomas. One patient had Stage II breast carcinoma; the other had metastatic disease. Characterisation of these lines has revealed that both are highly aneuploid containing multiple clonal chromosome alterations, have doubling times near 100 h, and are oestrogen and progesterone receptor negative. Electron microscopy demonstrates that both lines contain numerous microvilli, cytoplasmic filaments, multivesicular bodies, and desmosomes. Immunoblot analysis for P-glycoprotein using the monoclonal antibody C219 was negative for both patient cell lines. These relatively rare cell lines may represent a useful model to investigate human breast carcinomas. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:1674877

  20. Anti-Neoplastic Cytotoxicity of Gemcitabine-(C4-amide)-[anti-EGFR] in Dual-combination with Epirubicin-(C3-amide)-[anti-HER2/neu] against Chemotherapeutic-Resistant Mammary Adenocarcinoma (SKBr-3) and the Complementary Effect of Mebendazole

    PubMed Central

    Coyne, CP; Jones, Toni; Bear, Ryan

    2015-01-01

    Aims Delineate the feasibility of simultaneous, dual selective “targeted” chemotherapeutic delivery and determine if this molecular strategy can promote higher levels anti-neoplastic cytotoxicity than if only one covalent immunochemotherapeutic is selectively “targeted” for delivery at a single membrane associated receptor over-expressed by chemotherapeutic-resistant mammary adenocarcinoma. Methodology Gemcitabine and epirubicin were covalently bond to anti-EGFR and anti-HER2/neu utilizing a rapid multi-phase synthetic organic chemistry reaction scheme. Determination that 96% or greater gemcitabine or epirubicin content was covalently bond to immunoglobulin fractions following size separation by micro-scale column chromatography was established by methanol precipitation analysis. Residual binding-avidity of gemcitabine-(C4-amide)-[anti-EG-FR] applied in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu] was determined by cell-ELIZA utilizing chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) populations. Lack of fragmentation or polymerization was validated by SDS-PAGE/immunodetection/chemiluminescent autoradiography. Anti-neoplastic cytotoxic potency was determined by vitality stain analysis of chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) monolayers known to uniquely over-express EGFR (2 × 105/cell) and HER2/neu (1 × 106/cell) receptor complexes. The covalent immunochemotherapeutics gemcitabine-(C4-amide)-[anti-EGFR] and epirubicin-(C3-amide)-[anti-HER2/neu] were applied simultaneously in dual-combination to determine their capacity to collectively evoke elevated levels of anti-neoplastic cytotoxicity. Lastly, the tubulin/microtubule inhibitor mebendazole evaluated to determine if it’s potential to complemented the anti-neoplastic cytotoxic properties of gemcitabine-(C4-amide)-[anti-EGFR] in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu]. Results Dual-combination of gemcitabine-(C4-amide)-[anti-EGFR] with

  1. Dual HER2 blockade in the neoadjuvant and adjuvant treatment of HER2-positive breast cancer

    PubMed Central

    Advani, Pooja; Cornell, Lauren; Chumsri, Saranya; Moreno-Aspitia, Alvaro

    2015-01-01

    Human epidermal growth factor receptor 2 (HER2) is a tyrosine kinase transmembrane receptor that is overexpressed on the surface of 15%–20% of breast tumors and has been associated with poor prognosis. Consistently improved pathologic response and survival rates have been demonstrated with use of trastuzumab in combination with standard chemotherapy in both early and advanced breast cancer. However, resistance to trastuzumab may pose a major problem in the effective treatment of HER2-positive breast cancer. Dual HER2 blockade, using agents that work in a complimentary fashion to trastuzumab, has more recently been explored to evade resistance in both the preoperative (neoadjuvant) and adjuvant settings. Increased effectiveness of dual anti-HER2 agents over single blockade has been recently reported in clinical studies. Pertuzumab in combination with trastuzumab and taxane is currently approved in the metastatic and neoadjuvant treatment of HER2-positive breast cancer. Various biomarkers have also been investigated to identify subsets of patients with HER2-positive tumors who would likely respond best to these targeted therapy combinations. In this article, available trial data regarding efficacy and toxicity of treatment with combination HER2 agents in the neoadjuvant and adjuvant setting have been reviewed, and relevant correlative biomarker data from these trials have been discussed. PMID:26451122

  2. HER2-targeted liposomal doxorubicin displays enhanced anti-tumorigenic effects without associated cardiotoxicity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reynolds, Joseph G.; Geretti, Elena; Hendriks, Bart S.

    2012-07-01

    Anthracycline-based regimens are a mainstay of early breast cancer therapy, however their use is limited by cardiac toxicity. The potential for cardiotoxicity is a major consideration in the design and development of combinatorial therapies incorporating anthracyclines and agents that target the HER2-mediated signaling pathway, such as trastuzumab. In this regard, HER2-targeted liposomal doxorubicin was developed to provide clinical benefit by both reducing the cardiotoxicity observed with anthracyclines and enhancing the therapeutic potential of HER2-based therapies that are currently available for HER2-overexpressing cancers. While documenting the enhanced therapeutic potential of HER2-targeted liposomal doxorubicin can be done with existing models, there hasmore » been no validated human cardiac cell-based assay system to rigorously assess the cardiotoxicity of anthracyclines. To understand if HER2-targeting of liposomal doxorubicin is possible with a favorable cardiac safety profile, we applied a human stem cell-derived cardiomyocyte platform to evaluate the doxorubicin exposure of human cardiac cells to HER2-targeted liposomal doxorubicin. To the best of our knowledge, this is the first known application of a stem cell-derived system for evaluating preclinical cardiotoxicity of an investigational agent. We demonstrate that HER2-targeted liposomal doxorubicin has little or no uptake into human cardiomyocytes, does not inhibit HER2-mediated signaling, results in little or no evidence of cardiomyocyte cell death or dysfunction, and retains the low penetration into heart tissue of liposomal doxorubicin. Taken together, this data ultimately led to the clinical decision to advance this drug to Phase I clinical testing, which is now ongoing as a single agent in HER2-expressing cancers. -- Highlights: ► Novel approach using stem cell-derived cardiomyocytes to assess preclinical safety. ► HER2-targeted liposomal doxorubicin has improved safety profile vs free

  3. A Randomized Phase 2 Trial of 177Lu Radiolabeled Anti-PSMA Monoclonal Antibody J591 in Patients With High-Risk Castrate Biochemically Relapsed Prostate Cancer

    DTIC Science & Technology

    2015-09-01

    Award Number: W81XWH-09-1-0596 TITLE: A Randomized Phase 2 Trial of 177Lu Radiolabeled Anti- PSMA Monoclonal Antibody J591 in Patients With High...1-0596 A Randomized Phase 2 Trial of 177Lu Radiolabeled Anti- PSMA Monoclonal Antibody J591 in Patients With High-Risk Castrat Biochemically Relapsed...in December 2014 with approval to proceed without modifications. 15. SUBJECT TERMS Prostate cancer, PSA, PSMA , monoclonal antibody

  4. HER2 monoclonal antibodies that do not interfere with receptor heterodimerization-mediated signaling induce effective internalization and represent valuable components for rational antibody-drug conjugate design.

    PubMed

    de Goeij, Bart E C G; Peipp, Matthias; de Haij, Simone; van den Brink, Edward N; Kellner, Christian; Riedl, Thilo; de Jong, Rob; Vink, Tom; Strumane, Kristin; Bleeker, Wim K; Parren, Paul W H I

    2014-01-01

    The human epidermal growth factor receptor (HER)2 provides an excellent target for selective delivery of cytotoxic drugs to tumor cells by antibody-drug conjugates (ADC) as has been clinically validated by ado-trastuzumab emtansine (Kadcyla(TM)). While selecting a suitable antibody for an ADC approach often takes specificity and efficient antibody-target complex internalization into account, the characteristics of the optimal antibody candidate remain poorly understood. We studied a large panel of human HER2 antibodies to identify the characteristics that make them most suitable for an ADC approach. As a model toxin, amenable to in vitro high-throughput screening, we employed Pseudomonas exotoxin A (ETA') fused to an anti-kappa light chain domain antibody. Cytotoxicity induced by HER2 antibodies, which were thus non-covalently linked to ETA', was assessed for high and low HER2 expressing tumor cell lines and correlated with internalization and downmodulation of HER2 antibody-target complexes. Our results demonstrate that HER2 antibodies that do not inhibit heterodimerization of HER2 with related ErbB receptors internalize more efficiently and show greater ETA'-mediated cytotoxicity than antibodies that do inhibit such heterodimerization. Moreover, stimulation with ErbB ligand significantly enhanced ADC-mediated tumor kill by antibodies that do not inhibit HER2 heterodimerization. This suggests that the formation of HER2/ErbB-heterodimers enhances ADC internalization and subsequent killing of tumor cells. Our study indicates that selecting HER2 ADCs that allow piggybacking of HER2 onto other ErbB receptors provides an attractive strategy for increasing ADC delivery and tumor cell killing capacity to both high and low HER2 expressing tumor cells.

  5. Development of a Targeted anti-HER2 scFv Chimeric Peptide for Gene Delivery into HER2-Positive Breast Cancer Cells.

    PubMed

    Cheraghi, Roya; Nazari, Mahboobeh; Alipour, Mohsen; Majidi, Asia; Hosseinkhani, Saman

    2016-12-30

    Chimeric polymers are known as suitable carriers for gene delivery. Certain properties are critical for a polymer to be used as a gene delivery vector. A new polymer was designed for the targeted delivery of genes into breast cancer cell lines, based on MPG peptide. It is composed of different functional domains, including HIV gp41, nuclear localization sequence of SV40 T-antigen, two C-terminus repeats of histone H1, and the scFv of anti-HER2 antibody. The results demonstrated that the vector can effectively condense plasmid DNA into nanoparticles with an average size of 250nm. Moreover, fusion of the scFv portion to the carrier brought about the specific recognition of HER2. Overall, the transfection efficiency of the vector demonstrated that it could deliver the desired gene into BT-474 HER2-positive breast cancer cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Synergistic anti-tumor activity of Nimotuzumab in combination with Trastuzumab in HER2-positive breast cancer.

    PubMed

    Yang, Yun; Guo, Rui; Tian, Xiaoting; Zhang, Ziheng; Zhang, Pengfei; Li, Changzheng; Feng, Zhiwei

    2017-08-05

    Breast cancer is characterized with poor prognosis and high recurrence. HER2 is highly expressed in breast cancer and is a target for cancer therapy and prevention. Here, we investigated the anti-tumor activity of the combination of an HER2 inhibitor, trastuzumab with an EGFR-inhibitor, nimotuzumab in HER2-overexpressing breast cancer. Our data showed that a greater anti-tumor activity from the combination of trastuzumab and nimotuzumab than any alone usage of above antibody both in vitro and in vivo. Based on the combination index value, our data demonstrated that nimotuzumab synergistically enhanced trastuzumab-induced cell growth inhibition. Furthermore, we investigated the possible mechanism of this synergistic efficacy induced by trastuzumab plus nimotuzumab. Data showed that the combination was more potent in reducing the phosphorylation of HER2 and ERK1/2. We also found that the synergistic inhibition was partly attributed to the ROS generation and repression of NRF2 pathway that is known to promote cell growth. These results support the clinical development of this two-drug regimen for the treatment of HER2-amplified breast cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Anti-influenza M2e antibody

    DOEpatents

    Bradbury, Andrew M.

    2013-04-16

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  8. Anti-influenza M2e antibody

    DOEpatents

    Bradbury, Andrew M [Santa Fe, NM

    2011-12-20

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  9. Dual HER2 targeting impedes growth of HER2 gene-amplified uterine serous carcinoma xenografts.

    PubMed

    Groeneweg, Jolijn W; Hernandez, Silvia F; Byron, Virginia F; DiGloria, Celeste M; Lopez, Hector; Scialabba, Vanessa; Kim, Minji; Zhang, Ling; Borger, Darrell R; Tambouret, Rosemary; Foster, Rosemary; Rueda, Bo R; Growdon, Whitfield B

    2014-12-15

    Uterine serous carcinoma (USC) is an aggressive subtype of endometrial cancer that commonly harbors HER2 gene amplification. We investigated the effectiveness of HER2 inhibition using lapatinib and trastuzumab in vitro and in xenografts derived from USC cell lines and USC patient-derived xenografts. Immunohistochemistry and FISH were performed to assess HER2 expression in 42 primary USC specimens. ARK1, ARK2, and SPEC2 cell lines were treated with trastuzumab or lapatinib. Cohorts of mice harboring xenografts derived from ARK2 and SPEC2 cell lines and EnCa1 and EnCa2 primary human USC samples were treated with either vehicle, trastuzumab, lapatinib, or the combination of trastuzumab and lapatinib. Acute and chronic posttreatment tumor samples were assessed for downstream signaling alterations and examined for apoptosis and proliferation. HER2 gene amplification (24%) correlated significantly with HER2 protein overexpression (55%). All models were impervious to single-agent trastuzumab treatment. Lapatinib decreased in vitro proliferation of all cell lines and in vivo growth of HER2-amplified xenografts (ARK2, EnCa1). In addition, dual therapy with trastuzumab and lapatinib resulted in significant antitumor activity only in ARK2 and EnCa1 tumors. Dual HER2 therapy induced on target alteration of downstream MAPK and PI3K pathway mediators only in HER2-amplified models, and was associated with increased apoptosis and decreased proliferation. Although trastuzumab alone did not impact USC growth, dual anti-HER2 therapy with lapatinib led to improved inhibition of tumor growth in HER2-amplified USC and may be a promising avenue for future investigation. ©2014 American Association for Cancer Research.

  10. Label-free LC-MS analysis of HER2+ breast cancer cell line response to HER2 inhibitor treatment.

    PubMed

    Di Luca, Alessio; Henry, Michael; Meleady, Paula; O'Connor, Robert

    2015-08-04

    Human epidermal growth-factor receptor (HER)-2 is overexpressed in 25 % of breast-cancers and is associated with an aggressive form of the disease with significantly shortened disease free and overall survival. In recent years, the use of HER2-targeted therapies, monoclonal-antibodies and small molecule tyrosine-kinase inhibitors has significantly improved the clinical outcome for HER2-positive breast-cancer patients. However, only a fraction of HER2-amplified patients will respond to therapy and the use of these treatments is often limited by tumour drug insensitivity or resistance and drug toxicities. Currently there is no way to identify likely responders or rational combinations with the potential to improve HER2-focussed treatment outcome. In order to further understand the molecular mechanisms of treatment-response with HER2-inhibitors, we used a highly-optimised and reproducible quantitative label-free LC-MS strategy to characterize the proteomes of HER2-overexpressing breast-cancer cell-lines (SKBR3, BT474 and HCC1954) in response to drug-treatment with HER2-inhibitors (lapatinib, neratinib or afatinib). Following 12 ours treatment with different HER2-inhibitors in the BT474 cell-line; compared to the untreated cells, 16 proteins changed significantly in abundance following lapatinib treatment (1 μM), 21 proteins changed significantly following neratinib treatment (150 nM) and 38 proteins changed significantly following afatinib treatment (150 nM). Whereas following 24 hours treatment with neratinib (200 nM) 46 proteins changed significantly in abundance in the HCC1954 cell-line and 23 proteins in the SKBR3 cell-line compared to the untreated cells. Analysing the data we found that, proteins like trifunctional-enzyme subunit-alpha, mitochondrial; heterogeneous nuclear ribonucleoprotein-R and lamina-associated polypeptide 2, isoform alpha were up-regulated whereas heat shock cognate 71 kDa protein was down-regulated in 3 or more comparisons. This proteomic

  11. Regression of experimental medulloblastoma following transfer of HER2-specific T cells.

    PubMed

    Ahmed, Nabil; Ratnayake, Maheshika; Savoldo, Barbara; Perlaky, Laszlo; Dotti, Gianpietro; Wels, Winfried S; Bhattacharjee, Meenakshi B; Gilbertson, Richard J; Shine, H David; Weiss, Heidi L; Rooney, Cliona M; Heslop, Helen E; Gottschalk, Stephen

    2007-06-15

    Medulloblastoma is a common malignant brain tumor of childhood. Human epidermal growth factor receptor 2 (HER2) is expressed by 40% of medulloblastomas and is a risk factor for poor outcome with current aggressive multimodal therapy. In contrast to breast cancer, HER2 is expressed only at low levels in medulloblastomas, rendering monoclonal antibodies ineffective. We determined if T cells grafted with a HER2-specific chimeric antigen receptor (CAR; HER2-specific T cells) recognized and killed HER2-positive medulloblastomas. Ex vivo, stimulation of HER2-specific T cells with HER2-positive medulloblastomas resulted in T-cell proliferation and secretion of IFN-gamma and interleukin 2 (IL-2) in a HER2-dependent manner. HER2-specific T cells killed autologous HER2-positive primary medulloblastoma cells and medulloblastoma cell lines in cytotoxicity assays, whereas HER2-negative tumor cells were not killed. No functional difference was observed between HER2-specific T cells generated from medulloblastoma patients and healthy donors. In vivo, the adoptive transfer of HER2-specific T cells resulted in sustained regression of established medulloblastomas in an orthotopic, xenogenic severe combined immunodeficiency model. In contrast, delivery of nontransduced T cells did not change the tumor growth pattern. Adoptive transfer of HER2-specific T cells may represent a promising immunotherapeutic approach for medulloblastoma.

  12. Production of anti-CD14 monoclonal antibody using synthetic peptide of human CD14 as immunizing antigen.

    PubMed

    Maleki, Leili Aghebati; Shanehbandi, Dariush; Majidi, Jafar; Yusefi, Mehdi; Abdolalizadeh, Jalal; Orangi, Mona; Baradaran, Behzad

    2013-01-01

    CD14 is a myeloid differentiation antigen expressed primarily on peripheral blood monocytes, dendritic cells and macrophages. It is a key regulator of inflammatory responses to gram-negative bacteria, oxidative burst and septic shock. The aim of this study was to produce and characterize monoclonal antibody against CD14 for use in detection and diagnosis of monocytes. To produce MAb against CD14 protein, mice were immunized with two KLH-conjugated CD14 peptides. The spleen cells of the immunized mice were then fused with SP2/0 by hybridoma technique. Fused cells were grown in selective medium and cloned by limiting dilution method. The desired clones were selected and supernatants of hybridoma cells were screened by ELISA for antibody. Monoclonal antibody was purified by chromatography and confirmed by SDS-PAGE. Finally, immunoblotting and flowcytometry were recruited to explore the specificity of the MAb. Our results showed successful production and characterization of anti CD14 monoclonal antibody. The MAb was IgG2a with Kappa light chain and immunobloting and flowcytometry results demonstrated specific reactivity of this MAb with CD14. The results show that, the produced anti- CD14 MAb is highly specific and functional in biomedical applications such as flow cytometry and western blotting and could be utilized for identification of monocytes.

  13. Anti-HER2 antibody and ScFvEGFR-conjugated antifouling magnetic iron oxide nanoparticles for targeting and magnetic resonance imaging of breast cancer

    PubMed Central

    Chen, Hongwei; Wang, Liya; Yu, Qiqi; Qian, Weiping; Tiwari, Diana; Yi, Hong; Wang, Andrew Y; Huang, Jing; Yang, Lily; Mao, Hui

    2013-01-01

    Antifouling magnetic iron oxide nanoparticles (IONPs) coated with block copolymer poly(ethylene oxide)-block-poly(γ-methacryloxypropyltrimethoxysilane) (PEO-b-PγMPS) were investigated for improving cell targeting by reducing nonspecific uptake. Conjugation of a HER2 antibody, Herceptin®, or a single chain fragment (ScFv) of antibody against epidermal growth factor receptor (ScFvEGFR) to PEO-b-PγMPS-coated IONPs resulted in HER2-targeted or EGFR-targeted IONPs (anti-HER2-IONPs or ScFvEGFR-IONPs). The anti-HER2-IONPs bound specifically to SK-BR-3, a HER2-overexpressing breast cancer cell line, but not to MDA-MB-231, a HER2-underexpressing cell line. On the other hand, the ScFvEGFR-IONPs showed strong reactivity with MDA-MB-231, an EGFR-positive human breast cancer cell line, but not with MDA-MB-453, an EGFR-negative human breast cancer cell line. Transmission electron microscopy revealed internalization of the receptor-targeted nanoparticles by the targeted cancer cells. In addition, both antibody-conjugated and non-antibody-conjugated IONPs showed reduced nonspecific uptake by RAW264.7 mouse macrophages in vitro. The developed IONPs showed a long blood circulation time (serum half-life 11.6 hours) in mice and low accumulation in both the liver and spleen. At 24 hours after systemic administration of ScFvEGFR-IONPs into mice bearing EGFR-positive breast cancer 4T1 mouse mammary tumors, magnetic resonance imaging revealed signal reduction in the tumor as a result of the accumulation of the targeted IONPs. PMID:24124366

  14. Treatment of oral squamous cell carcinoma using anti-HER2 immunonanoshells

    PubMed Central

    Fekrazad, Reza; Hakimiha, Neda; Farokhi, Enice; Rasaee, Mohammad Javad; Ardestani, Mehdi Shafiee; Kalhori, Katayoun AM; Sheikholeslami, Farzaneh

    2011-01-01

    Background Worldwide, oral squamous cell carcinoma (potentially mediated by HER2) is recognized as the most commonly occurring malignant neoplasm of the oral cavity. Anti-HER2 nanobodies conjugated to gold-silica nanoshells and used as photothermal treatment for oral squamous cell carcinoma may provide a novel therapeutic alternative to current treatment for this disease. Methods KB epithelial or HeLaS3 cell cultures (controls) were exposed to these immunonanoshells, and plasmon resonance electron initiation specific to gold was employed to burn the tumor cells. Results Following this treatment, significant cell death occurred in the KB tumor cell cultures while there was no evidence of cellular damage or death in the HeLaS3 cell cultures. Conclusion These findings suggest that photothermal treatment of oral squamous cell carcinoma has considerable advantages. PMID:22131825

  15. Treatment of oral squamous cell carcinoma using anti-HER2 immunonanoshells.

    PubMed

    Fekrazad, Reza; Hakimiha, Neda; Farokhi, Enice; Rasaee, Mohammad Javad; Ardestani, Mehdi Shafiee; Kalhori, Katayoun A M; Sheikholeslami, Farzaneh

    2011-01-01

    Worldwide, oral squamous cell carcinoma (potentially mediated by HER2) is recognized as the most commonly occurring malignant neoplasm of the oral cavity. Anti-HER2 nanobodies conjugated to gold-silica nanoshells and used as photothermal treatment for oral squamous cell carcinoma may provide a novel therapeutic alternative to current treatment for this disease. KB epithelial or HeLaS3 cell cultures (controls) were exposed to these immunonanoshells, and plasmon resonance electron initiation specific to gold was employed to burn the tumor cells. Following this treatment, significant cell death occurred in the KB tumor cell cultures while there was no evidence of cellular damage or death in the HeLaS3 cell cultures. These findings suggest that photothermal treatment of oral squamous cell carcinoma has considerable advantages.

  16. Expression of full-length HER2 protein in Sf9 insect cells and its presentation on the surface of budded virus-like particles.

    PubMed

    Nika, Lisa; Wallner, Jakob; Palmberger, Dieter; Koczka, Krisztina; Vorauer-Uhl, Karola; Grabherr, Reingard

    2017-08-01

    Biomarkers of cancer are often glycosylated membrane receptor proteins present on the cellular surface. In order to develop new antibodies for cancer diagnostics or treatment, it is a main pre-requisite that these target proteins are available in a native conformation. However, membrane receptor proteins are notoriously difficult to produce due to their hydrophobic nature and complex architecture. Here, we used the baculovirus-insect cell expression system to produce budded virus-like particles (VLPs) as the scaffold for the presentation of complex membrane proteins. Since the human epidermal growth factor receptor 2 (HER2) is known to be overexpressed in a number of cancers it was chosen as model for a tumor antigen. VLPs displaying full-length HER2 on the surface were produced in Spodoptera frugiperda 9 (Sf9) insect cells and purified by sucrose gradient ultracentrifugation. The number of secreted particles was quantified by nanoparticle tracking analysis. To confirm the presence of HER2 protein on the surface, VLPs were labeled with gold-conjugated antibodies and analyzed by transmission electron microscopy. Functionality of displayed HER2 was investigated by ELISA and a newly established biolayer interferometry based technique. Detection was accomplished using the specific monoclonal antibody Herceptin and filamentous phages displaying a single-chain variable fragment of an anti-HER2 antibody. Significant stronger binding of Herceptin and anti-HER2 phages to HER2-displaying VLPs as compared to control VLPs was demonstrated. Thus, we suggest that Sf9 insect cells are highly feasible for the fast and easy production of various budded VLPs that serve as a platform for full-length membrane receptor presentation. Copyright © 2017. Published by Elsevier Inc.

  17. Anti-tumor activity of the ATR inhibitor AZD6738 in HER2 positive breast cancer cells.

    PubMed

    Kim, Hee-Jun; Min, Ahrum; Im, Seock-Ah; Jang, Hyemin; Lee, Kyung Hun; Lau, Alan; Lee, Miso; Kim, Seongyeong; Yang, Yaewon; Kim, Jungeun; Kim, Tae Yong; Oh, Do-Youn; Brown, Jeffrey; O'Connor, Mark J; Bang, Yung-Jue

    2017-01-01

    Ataxia telangiectasia and Rad3-related (ATR) proteins are sensors of DNA damage, which induces homologous recombination (HR)-dependent repair. ATR is a master regulator of DNA damage repair (DDR), signaling to control DNA replication, DNA repair and apoptosis. Therefore, the ATR pathway might be an attractive target for developing new drugs. This study was designed to investigate the antitumor effects of the ATR inhibitor, AZD6738 and its underlying mechanism in human breast cancer cells. Growth inhibitory effects of AZD6738 against human breast cancer cell lines were studied using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (methyl thiazolyl tetrazolium, MTT) assay. Cell cycle analysis, Western blotting, immunofluorescence and comet assays were also performed to elucidate underlying mechanisms of AZD6738 action. Anti-proliferative and DDR inhibitory effects of AZD6738 were demonstrated in human breast cancer cell lines. Among 13 cell lines, the IC 50 values of nine cell lines were less than 1 μmol/L using MTT assay. Two cell lines, SK-BR-3 and BT-474, were chosen for further evaluation focused on human epidermal growth factor receptor 2 (HER2)-positive breast cancer cells. Sensitive SK-BR-3 but not the less sensitive BT-474 breast cancer cells showed increased level of apoptosis and S phase arrest and reduced expression levels of phosphorylated check-point kinase 1 (CHK1) and other repair markers. Decreased functional CHK1 expression induced DNA damage accumulation due to HR inactivation. AZD6738 showed synergistic activity with cisplatin. Understanding the antitumor activity and mechanisms of AZD6738 in HER2-positive breast cancer cells creates the possibility for future clinical trials targeting DDR in HER2-positive breast cancer treatment. © 2016 UICC.

  18. Combined use of anti-ErbB monoclonal antibodies and erlotinib enhances antibody-dependent cellular cytotoxicity of wild-type erlotinib-sensitive NSCLC cell lines

    PubMed Central

    2012-01-01

    Background The epidermal growth factor receptor (EGFR) is an established target for anti-cancer treatment in different tumour types. Two different strategies have been explored to inhibit this pivotal molecule in epithelial cancer development: small molecules TKIs and monoclonal antibodies. ErbB/HER-targeting by monoclonal antibodies such as cetuximab and trastuzumab or tyrosine-kinase inhibitors as gefitinib or erlotinib has been proven effective in the treatment of advanced NSCLC. Results In this study we explored the potential of combining either erlotinib with cetuximab or trastuzumab to improve the efficacy of EGFR targeted therapy in EGFR wild-type NSCLC cell lines. Erlotinib treatment was observed to increase EGFR and/or HER2 expression at the plasma membrane level only in NSCLC cell lines sensitive to the drug inducing protein stabilization. The combined treatment had marginal effect on cell proliferation but markedly increased antibody-dependent, NK mediated, cytotoxicity in vitro. Moreover, in the Calu-3 xenograft model, the combination significantly inhibited tumour growth when compared with erlotinib and cetuximab alone. Conclusion Our results indicate that erlotinib increases surface expression of EGFR and/or HER2 only in EGFR-TKI sensitive NSCLC cell lines and, in turns, leads to increased susceptibility to ADCC both in vitro and in a xenograft models. The combination of erlotinib with monoclonal antibodies represents a potential strategy to improve the treatment of wild-type EGFR NSCLC patients sensitive to erlotinib. PMID:23234355

  19. Dual-targeting hybrid nanoparticles for the delivery of SN38 to Her2 and CD44 overexpressed human gastric cancer

    NASA Astrophysics Data System (ADS)

    Yang, Zhe; Luo, Huiyan; Cao, Zhong; Chen, Ya; Gao, Jinbiao; Li, Yingqin; Jiang, Qing; Xu, Ruihua; Liu, Jie

    2016-06-01

    Gastric cancer (GC), particularly of the type with high expression of both human epidermal growth factor receptor 2 (Her2) and cluster determinant 44 (CD44), is one of the most malignant human tumors which causes a high mortality rate due to rapid tumor growth and metastasis. To develop effective therapeutic treatments, a dual-targeting hybrid nanoparticle (NP) system was designed and constructed to deliver the SN38 agent specifically to human solid gastric tumors bearing excessive Her2 and CD44. The hybrid NPs consist of a particle core made of the biodegradable polymer PLGA and a lipoid shell prepared by conjugating the AHNP peptides and n-hexadecylamine (HDA) to the carboxyl groups of hyaluronic acid (HA). Upon encapsulation of the SN38 agent in the NPs, the AHNP peptides and HA on the NP surface allow preferential delivery of the drug to gastric cancer cells (e.g., HGC27 cells) by targeting Her2 and CD44. Cellular uptake and in vivo biodistribution experiments verified the active targeting and prolonged in vivo circulation properties of the dual-targeting hybrid NPs, leading to enhanced accumulation of the drug in tumors. Furthermore, the anti-proliferation mechanism studies revealed that the inhibition of the growth and invasive activity of HGC27 cells was not only attributed to the enhanced cellular uptake of dual-targeting NPs, but also benefited from the suppression of CD44 and Her2 expression by HA and AHNP moieties. Finally, intravenous administration of the SN38-loaded dual-targeting hybrid NPs induced significant growth inhibition of HGC27 tumor xenografted in nude mice compared with a clinical antitumor agent, Irinotecan (CPT-11), and the other NP formulations. These results demonstrate that the designed dual-targeting hybrid NPs are promising for targeted anti-cancer drug delivery to treat human gastric tumors over-expressing Her2 and CD44.Gastric cancer (GC), particularly of the type with high expression of both human epidermal growth factor receptor

  20. Basal/HER2 breast carcinomas

    PubMed Central

    Martin-Castillo, Begoña; Oliveras-Ferraros, Cristina; Vazquez-Martin, Alejandro; Cufí, Silvia; Moreno, José Manuel; Corominas-Faja, Bruna; Urruticoechea, Ander; Martín, Ángel G.; López-Bonet, Eugeni; Menendez, Javier A.

    2013-01-01

    High rates of inherent primary resistance to the humanized monoclonal antibody trastuzumab (Herceptin) are frequent among HER2 gene-amplified breast carcinomas in both metastatic and adjuvant settings. The clinical efficacy of trastuzumab is highly correlated with its ability to specifically and efficiently target HER2-driven populations of breast cancer stem cells (CSCs). Intriguingly, many of the possible mechanisms by which cancer cells escape trastuzumab involve many of the same biomarkers that have been implicated in the biology of CS-like tumor-initiating cells. In the traditional, one-way hierarchy of CSCs in which all cancer cells descend from special self-renewing CSCs, HER2-positive CSCs can occur solely by self-renewal. Therefore, by targeting CSC self-renewal and resistance, trastuzumab is expected to induce tumor shrinkage and further reduce breast cancer recurrence rates when used alongside traditional therapies. In a new, alternate model, more differentiated non-stem cancer cells can revert to trastuzumab-refractory, CS-like cells via the activation of intrinsic or microenvironmental paths-to-stemness, such as the epithelial-to-mesenchymal transition (EMT). Alternatively, stochastic transitions of trastuzumab-responsive CSCs might also give rise to non-CSC cellular states that lack major attributes of CSCs and, therefore, can remain “hidden” from trastuzumab activity. Here, we hypothesize that a better understanding of the CSC/non-CSC social structure within HER2-overexpressing breast carcinomas is critical for trastuzumab-based treatment decisions in the clinic. First, we decipher the biological significance of CSC features and the EMT on the molecular effects and efficacy of trastuzumab in HER2-positive breast cancer cells. Second, we reinterpret the genetic heterogeneity that differentiates trastuzumab-responders from non-responders in terms of CSC cellular states. Finally, we propose that novel predictive approaches aimed at better

  1. Polyethylene glycol-conjugated HER2-targeted peptides as a nuclear imaging probe for HER2-overexpressed gastric cancer detection in vivo.

    PubMed

    Guan, Siao-Syun; Wu, Cheng-Tien; Chiu, Chen-Yuan; Luo, Tsai-Yueh; Wu, Jeng-Yih; Liao, Tse-Zung; Liu, Shing-Hwa

    2018-06-19

    The human epidermal growth factor receptor 2 (HER2) involved proliferation, angiogenesis, and reduced apoptosis in gastric cancer (GC), which is a common target for tumor therapy. HER2 is usually overexpressed in more than 15% GC patients, developing a reliable diagnostic tool for tumor HER2 detection is important. In this study, we attend to use polyethylene glycol (PEG) linked anti-HER2/neu peptide (AHNP-PEG) as a nuclear imaging agent probe for HER2 detection in GC xenograft animal model. The HER2 expression of human sera and tissues were detected in GC patients and normal subjects. GC cell lines NCI-N87 (high HER2 levels) and MKN45 (low HER2 levels) were treated with AHNP-PEG to assess the cell viability and HER2 binding ability. The NCI-N87 was treated with AHNP-PEG to observe the level and phosphorylation of HER2. The MKN45 and NCI-N87-induced xenograft mice were intravenous injection with fluorescence labeled AHNP-PEG for detecting in vivo fluorescence imaging properties and biodistribution. The AHNP-PEG was conjugated with diethylenetriaminopentaacetic acid (DTPA) for indium-111 labeling ( 111 In-DTPA-AHNP-PEG). The stability of was assessed in vitro. The imaging properties and biodistribution of 111 In-DTPA-AHNP-PEG were observed in NCI-N87-induced xenograft mice. The serum HER2 (sHER2) levels in GC patients were significantly higher than the normal subjects. The sHER2 levels were correlated with the tumor HER2 levels in different stages of GC patients. The AHNP-PEG inhibited the cell growth and down-regulated HER2 phosphorylation in HER2-overexpressed human GC cells (NCI-N87) via specific HER2 interaction of cell surface. In addition, the GC tumor tissues from HER2-postive xenograft mice presented higher HER2 fluorescence imaging as compared to HER2-negative group. The HER2 levels in the tumor tissues were also higher than other organs in NCI-N87-induced xenograft mice. Finally, we further observed that the 111 In-DTPA-AHNP-PEG was significantly enhanced

  2. Common idiotypes expressed on human, monoclonal, abnormal immunoglobulins and cryoglobulins with polyreactive autoantibody activities.

    PubMed Central

    Barbouche, M R; Guilbert, B; Makni, S; Gorgi, Y; Ayed, K; Avrameas, S

    1993-01-01

    Several human monoclonal immunoglobulins with the same autoantibody activity have been shown to have cross-reactive idiotypes (CRI). In this study, using polyclonal anti-idiotypic antibodies, we found that 28% of human monoclonal immunoglobulins with polyreactive autoantibody activity from myeloma, Waldenström's macroglobulinaemia and cryoglobulinaemia patients shared common idiotype(s). Furthermore, the latter were expressed on human and murine natural MoAbs (respectively in 12% and 22% of the clones tested) and on human IgG preparations used for therapeutic intravenous injections (IVIg) and which contain natural antibodies. These findings suggest that monoclonal immunoglobulins could arise from the proliferation of a clone that normally produces a natural antibody. The existence of common idiotype(s) between monoclonal immunoglobulins and IVIg could be relevant to the improvement noted after treatment with IVIg in patients suffering from peripheral neuropathies associated with monoclonal gammopathy. PMID:8428386

  3. Evaluation of dry blood spot technique for quantification of an Anti-CD20 monoclonal antibody drug in human blood samples.

    PubMed

    Lin, Yong-Qing; Zhang, Yilu; Li, Connie; Li, Louis; Zhang, Kelley; Li, Shawn

    2012-01-01

    To evaluate the dried blood spot (DBS) technique in ELISA quantification of larger biomolecular drugs, an anti-CD20 monoclonal antibody drug was used as an example. A method for the quantification of the anti-CD20 drug in human DBS was developed and validated. The drug standard and quality control samples prepared in fresh human blood were spotted on DBS cards and then extracted. A luminescent ELISA was used for quantification of the drug from DBS samples. The assay range of the anti-CD20 drug standards in DBS was 100-2500ng/mL. The intra-assay precision (%CV) ranged from 0.4% to 10.1%, and the accuracy (%Recovery) ranged from 77.9% to 113.9%. The inter assay precision (%CV) ranged from 5.9% to 17.4%, and the accuracy ranged from 81.5% to 110.5%. The DBS samples diluted 500 and 50-fold yielded recovery of 88.7% and 90.7%, respectively. The preparation of DBS in higher and lower hematocrit (53% and 35%) conditions did not affect the recovery of the drug. Furthermore, the storage stability of the anti-CD20 drug on DBS cards was tested at various conditions. It was found that the anti-CD20 drug was stable for one week in DBS stored at room temperature. However, it was determined that the stability was compro]mised in DBS stored at high humidity, high temperature (55°C), and exposed to direct daylight for a week, as well as for samples stored at room temperature and high humidity conditions for a month. Stability did not change significantly in samples that underwent 3 freeze/thaw cycles. Our results demonstrated a successful use of DBS technique in ELISA quantification of an anti-CD20 monoclonal antibody drug in human blood. The stability data provides information regarding sample storage and shipping for future clinical studies. It is, therefore, concluded that the DBS technique is applicable in the quantification of other large biomolecule drugs or biomarkers. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Evaluation of monoclonal anti-A and anti-B and affinity-purified Ulex europaeus lectin I for forensic blood grouping.

    PubMed

    Gaensslen, R E; Lee, H C; Carroll, J E

    1984-01-01

    Two different monoclonal anti-A and anti-B and several different affinity purified Ulex europaeus lectin I reagents were evaluated and compared with conventional anti-A and anti-B sera and Ulex anti-H for serologic properties, in inhibition tests with secretor salivas, and in elution tests with bloodstains. The monoclonal and purified reagents were found to be comparable to conventional ones, and accordingly suitable for forensic inhibition and elution procedures.

  5. [Diagnostic and therapeutic use of human anti-D (Rho) monoclonal antibodies. Evaluation and perspectives].

    PubMed

    Rouger, P; Goossens, D; Champomier, F; Tsikas, G; Liberge, G; Leblanc, J; Richard, C; Bailleul, C; Salmon, C

    1985-12-01

    Human monoclonal antibodies will be essential in medicine. They are valuable tools for biological diagnosis and therapeutics. Our model, human monoclonal antibodies directed against the Rhesus D antigen can be used for the determination of the Rhesus D phenotype and for the suppression of Rh(D) immunisation in women. These new products require new procedures of preparation, new regulations for the quality controls, which will be discussed in this paper.

  6. In situ demonstration of tissue proliferative activity using anti-bromo-deoxyuridine monoclonal antibody.

    PubMed Central

    Veronese, S; Gambacorta, M; Falini, B

    1989-01-01

    Immunohistochemical staining with anti-bromo-deoxyuridine (BrdU) monoclonal antibody was performed on a variety of human tissues following in vitro incubation with BrdU. The effect of different fixatives and DNA denaturation techniques on the reactivity with anti-BrdU was investigated. Optimal preservation of the antigenicity of BrdU incorporated into the DNA of proliferating cells was seen in tissues fixed in Bouin's fluid, while samples which had been fixed with cross-linking reagents, such as formalin, were usually unreactive. Positivity for BrdU was restored in formalin fixed tissues after digestion with pepsin, but this was usually associated with loss of morphological details. Acid and thermal DNA denaturation techniques gave similar results. It is concluded that Bouin fixation followed by acid or thermal denaturation of DNA is the method of choice for the in situ detection of cells in S-phase using anti-BrdU monoclonal antibody. Images Fig 1 Fig 1 PMID:2475528

  7. Grb2-SH3 ligand inhibits the growth of HER2+ cancer cells and has antitumor effects in human cancer xenografts alone and in combination with docetaxel

    PubMed Central

    Gril, Brunilde; Vidal, Michel; Assayag, Franck; Poupon, Marie-France; Liu, Wang-Qing; Garbay, Christiane

    2007-01-01

    HER2 represents an important signaling pathway in breast and other cancers. Herceptin has demonstrated clinical activity, but resistance is common. Thus, new therapeutic approaches to the HER2 pathway are needed. Grb2 is an adaptor protein involved in Ras-dependent signaling induced by HER2 receptors. A specific Grb2-SH3 ligand, designed and synthesized in our laboratory, called peptidimer-c, inhibited colony formation in HER2 over-expressing SKBr3 cancer cells. Combined treatment of peptidimer-c with docetaxel further inhibited both colony formation and tumor cell survival compared to docetaxel treatment alone. Efficacy of this combined treatment was correlated with a reduction in the phosphorylation of MAPK and AKT. Finally, peptidimer-c reduced the growth of a HER2+ human breast cancer (BK111) xenograft in nude mice and potentiated the anti-tumor effect of docetaxel in a HER2+ hormone-independent human prostate adenocarcinoma (PAC120 HID28) xenograft. These results validate Grb2 as a new target for the HER2 pathway. PMID:17372910

  8. Anti-respiratory syncytial virus (RSV) G monoclonal antibodies reduce lung inflammation and viral lung titers when delivered therapeutically in a BALB/c mouse model.

    PubMed

    Caidi, Hayat; Miao, Congrong; Thornburg, Natalie J; Tripp, Ralph A; Anderson, Larry J; Haynes, Lia M

    2018-06-01

    RSV continues to be a high priority for vaccine and antiviral drug development. Unfortunately, no safe and effective RSV vaccine is available and treatment options are limited. Over the past decade, several studies have focused on the role of RSV G protein on viral entry, viral neutralization, and RSV-mediated pathology. Anti-G murine monoclonal antibody (mAb) 131-2G treatment has been previously shown to reduce weight loss, bronchoalveolar lavage (BAL) cell number, airway reactivity, and Th2-type cytokine production in RSV-infected mice more rapidly than a commercial humanized monoclonal antibody (mAb) against RSV F protein (Palivizumab). In this study, we have tested two human anti-RSV G mAbs, 2B11 and 3D3, by both prophylactic and therapeutic treatment for RSV in the BALB/c mouse model. Both anti-G mAbs reduced viral load, leukocyte infiltration and IFN-γ and IL-4 expression in cell-free BAL supernatants emphasizing the potential of anti-G mAbs as anti-inflammatory and antiviral strategies. Published by Elsevier B.V.

  9. Aloe-emodin inhibits HER-2 expression through the downregulation of Y-box binding protein-1 in HER-2-overexpressing human breast cancer cells.

    PubMed

    Ma, Jui-Wen; Hung, Chao-Ming; Lin, Ying-Chao; Ho, Chi-Tang; Kao, Jung-Yie; Way, Tzong-Der

    2016-09-13

    Human epidermal growth factor receptor-2 (HER-2)-positive breast cancer tends to be aggressive, highly metastatic, and drug resistant and spreads rapidly. Studies have indicated that emodin inhibits HER-2 expression. This study compared the HER-2-inhibitory effects of two compounds extracted from rhubarb roots: aloe-emodin (AE) and rhein. Our results indicated that AE exerted the most potent inhibitory effect on HER-2 expression. Treatment of HER-2-overexpressing breast cancer cells with AE reduced tumor initiation, cell migration, and cell invasion. AE was able to suppress YB-1 expression, further suppressing downstream HER-2 expression. AE suppressed YB-1 expression through the inhibition of Twist in HER-2-overexpressing breast cancer cells. Our data also found that AE inhibited cancer metastasis and cancer stem cells through the inhibition of EMT. Interestingly, AE suppressed YB-1 expression through the downregulation of the intracellular integrin-linked kinase (ILK)/protein kinase B (Akt)/mTOR signaling pathway in HER-2-overexpressing breast cancer cells. In vivo study showed the positive result of antitumor activity of AE in nude mice injected with human HER-2-overexpressing breast cancer cells. These findings suggest the possible application of AE in the treatment of HER-2-positive breast cancer.

  10. [Targeting of membrane receptor tyrosine kinases: is there resistance in the HER?].

    PubMed

    Monnier, Lucile; Milano, Gérard; Penault-Llorca, Frédérique; Merlin, Jean-Louis

    2004-09-01

    Human Epidermal growth factor Receptors (HER) play an important role in cellular proliferation, and differentiation. Their overexpression in tumor tissues is often associated with a poor prognosis. Consequently, HER receptors are interesting therapeutic targets for cancer treatment. Two strategies are proposed. First, monoclonal antibodies can be used to inhibit the binding of one ligand to its receptor. The second approach is based upon the designing of tyrosine kinase inhibitors capable to bind into the phosphorylation site of the receptor. Consequently, both approaches block the signal transduction downstream. Resistance to anti receptor tyrosine kinase therapy can lead to enhanced morbidity associated with high therapeutic cost. Different mechanisms can be implicated. Non specific mechanisms include alterations of the signal transduction pathways (PI3K/AKT), recruitment of alternative receptor tyrosine kinase pathways (IGFR, VEGFR) and proteasome degradation inhibition. Other mechanisms are specific to HER and rely on inhibition of the binding of monoclonal antibodies (sialomucin-MUC4), heterodimerisation of HER, truncated soluble receptors intervention and mutated variants, as demonstrated very recently with EGF receptors, or genetic polymorphism. This paper reviews these different resistance mechanisms that have been identified in preclinical and clinical situations.

  11. HER2 induces expression of leptin in human breast epithelial cells.

    PubMed

    Cha, Yujin; Kang, Youjin; Moon, Aree

    2012-12-01

    A close association between the obesity hormone leptin and breast cancer progression has been suggested. The present study investigated the molecular mechanism for enhanced leptin expression in breast cancer cells and its functional significance in breast cancer aggressiveness. We examined whether leptin expression level is affected by the oncoprotein human epidermal growth factor receptor2 (HER2), which is overexpressed in ∼30% of breast tumors. Here, we report, for the first time, that HER2 induces transcriptional activation of leptin in MCF10A human breast epithelial cells. We also showed that p38 mitogen-activated protein kinase signaling was involved in leptin expression induced by HER2. We showed a crucial role of leptin in the invasiveness of HER2-MCF10A cells using an siRNA molecule targeting leptin. Taken together, the results indicate a molecular link between HER2 and leptin, providing supporting evidence that leptin represents a target for breast cancer therapy. [BMB Reports 2012; 45(12): 719-723].

  12. HER2 induces expression of leptin in human breast epithelial cells

    PubMed Central

    Cha, Yujin; Kang, Youjin; Moon, Aree

    2012-01-01

    A close association between the obesity hormone leptin and breast cancer progression has been suggested. The present study investigated the molecular mechanism for enhanced leptin expression in breast cancer cells and its functional significance in breast cancer aggressiveness. We examined whether leptin expression level is affected by the oncoprotein human epidermal growth factor receptor2 (HER2), which is overexpressed in ∼30% of breast tumors. Here, we report, for the first time, that HER2 induces transcriptional activation of leptin in MCF10A human breast epithelial cells. We also showed that p38 mitogen-activated protein kinase signaling was involved in leptin expression induced by HER2. We showed a crucial role of leptin in the invasiveness of HER2-MCF10A cells using an siRNA molecule targeting leptin. Taken together, the results indicate a molecular link between HER2 and leptin, providing supporting evidence that leptin represents a target for breast cancer therapy. [BMB Reports 2012; 45(12): 719-723] PMID:23261058

  13. HER2 mutated breast cancer responds to treatment with single agent neratinib, a second generation HER2/EGFR tyrosine kinase inhibitor

    PubMed Central

    Ben–Baruch, Noa Efrat; Bose, Ron; Kavuri, Shyam M.; Ma, Cynthia X.; Ellis, Matthew J.

    2015-01-01

    Activating mutations in the HER2 tyrosine kinase have been identified in human breast cancers that lack HER2 gene amplification. These patients are not candidates for HER2 targeted drugs under current standards of care, but preclinical data strongly suggest that these patients will benefit from anti-HER2 drugs. In this case report, we describe a young woman with metastatic breast cancer whose tumor was found to carry a HER2 L755S mutation, which is in the kinase domain of HER2. Treatment with the second generation HER2/EGFR tyrosine kinase inhibitor, neratinib, resulted in partial response and dramatic improvement in the patient’s function status. This partial response lasted 11 months and when the patient’s cancer progressed, she was treated with neratinib plus capecitabine and her cancer again responded. This second response parallels the benefit seen with continuing trastuzumab in HER2 amplified breast cancer after disease progression. This case is the first report, to our knowledge, of successful single agent treatment of HER2 mutated breast cancer. Two clinical trials of neratinib for HER2 mutated, metastatic breast cancer are currently enrolling patients. Further, data from The Cancer Genome Atlas project have identified HER2 mutations in a wide range of solid tumors, including bladder, colorectal, and non-small cell lung cancer, suggesting that clinical trials of neratinib or neratinib-based combinations for HER2 mutated solid tumors is warranted. PMID:26358790

  14. HER2-Mutated Breast Cancer Responds to Treatment With Single-Agent Neratinib, a Second-Generation HER2/EGFR Tyrosine Kinase Inhibitor.

    PubMed

    Ben-Baruch, Noa Efrat; Bose, Ron; Kavuri, Shyam M; Ma, Cynthia X; Ellis, Matthew J

    2015-09-01

    Activating mutations in the HER2 tyrosine kinase have been identified in human breast cancers that lack HER2 gene amplification. These patients are not candidates for HER2-targeted drugs under current standards of care, but preclinical data strongly suggest that these patients will benefit from anti-HER2 drugs. This case report describes a young woman with metastatic breast cancer whose tumor was found to carry a HER2 L755S mutation, which is in the kinase domain of HER2. Treatment with the second-generation HER2/EGFR tyrosine kinase inhibitor neratinib resulted in partial response and dramatic improvement in the patient's functional status. This partial response lasted 11 months, and when the patient's cancer progressed, she was treated with neratinib plus capecitabine and her cancer again responded. This second response parallels the benefit seen with continuing trastuzumab in HER2-amplified breast cancer after disease progression. This case represents the first report, to our knowledge, of successful single-agent treatment of HER2-mutated breast cancer. Two clinical trials of neratinib for HER2-mutated metastatic breast cancer are currently enrolling patients. Further, data from The Cancer Genome Atlas project have identified HER2 mutations in a wide range of solid tumors, including bladder, colorectal, and non-small cell lung cancers, suggesting that clinical trials of neratinib or neratinib-based combinations for HER2-mutated solid tumors is warranted. Copyright © 2015 by the National Comprehensive Cancer Network.

  15. Quantification and imaging of HER2 protein using nanocrystals conjugated with single-domain antibodies

    NASA Astrophysics Data System (ADS)

    Glukhov, S.; Berestovoy, M.; Chames, P.; Baty, D.; Nabiev, I.; Sukhanova, A.

    2017-01-01

    This study dealt with quantification and imaging of human epidermal growth factor receptor 2 (HER2), an important prognostic marker for cancer diagnosis and treatment, using specific quantum-dot-based conjugates. Fluorescent inorganic nanocrystals or quantum dots (QDs) are extremely highly resistant to photobleaching and have a high emission quantum yield and a continuous range of emission spectra, from the ultraviolet to the infrared regions. Ultrasmall nanoprobes consisting of highly affine anti-HER2 single-domain antibodies (sdAbs or "nanobodies") conjugated with QDs in a strictly oriented manner have been designed. QDs with a fluorescence peak maxima at wavelengths of 562 nm, 569 nm, 570 nm or in the near-infrared region were used. Here, we present our results of ISA quantification of HER2 protein, in situ imaging of HER2 protein on the surface of HER2-positive SK-BR-3 cells in immunohistochemical experiments, and counting of stained with anti-HER2 conjugates HER2-positive SK-BR-3 cells in their mixture with unstained cells of the same culture in flow cytometry experiments. The data demonstrate that the anti-HER2 QD-sdAb conjugates obtained are highly specific and sensitive and could be used in numerous applications for advanced integrated diagnosis.

  16. Validation of a fully automated HER2 staining kit in breast cancer.

    PubMed

    Moelans, Cathy B; Kibbelaar, Robby E; van den Heuvel, Marius C; Castigliego, Domenico; de Weger, Roel A; van Diest, Paul J

    2010-01-01

    Testing for HER2 amplification and/or overexpression is currently routine practice to guide Herceptin therapy in invasive breast cancer. At present, HER2 status is most commonly assessed by immunohistochemistry (IHC). Standardization of HER2 IHC assays is of utmost clinical and economical importance. At present, HER2 IHC is most commonly performed with the HercepTest which contains a polyclonal antibody and applies a manual staining procedure. Analytical variability in HER2 IHC testing could be diminished by a fully automatic staining system with a monoclonal antibody. 219 invasive breast cancers were fully automatically stained with the monoclonal antibody-based Oracle HER2 Bond IHC kit and manually with the HercepTest. All cases were tested for amplification with chromogenic in situ hybridization (CISH). HercepTest yielded an overall sharper membrane staining, with less cytoplasmic and stromal background than Oracle in 17% of cases. Overall concordance between both IHC techniques was 89% (195/219) with a kappa value of 0.776 (95% CI 0.698-0.854), indicating a substantial agreement. Most (22/24) discrepancies between HercepTest and Oracle showed a weaker staining for Oracle. Thirteen of the 24 discrepant cases were high-level HER2 amplified by CISH, and in 12 of these HercepTest IHC better reflected gene amplification status. All the 13 HER2 amplified discrepant cases were at least 2+ by HercepTest, while 10/13 of these were at least 2+ for Oracle. Considering CISH as gold standard, sensitivity of HercepTest and Oracle was 91% and 83%, and specificity was 94% and 98%, respectively. Positive and negative predictive values for HercepTest and Oracle were 90% and 95% for HercepTest and 96% and 91% for Oracle, respectively. Fully-automated HER2 staining with the monoclonal antibody in the Oracle kit shows a high level of agreement with manual staining by the polyclonal antibody in the HercepTest. Although Oracle shows in general some more cytoplasmic staining and may

  17. Antibody-mediated immune suppression is improved when blends of anti-RBC monoclonal antibodies are used in mice.

    PubMed

    Bernardo, Lidice; Amash, Alaa; Marjoram, Danielle; Lazarus, Alan H

    2016-08-25

    Although the prevention of hemolytic disease of the fetus and newborn is highly effective using polyclonal anti-D, a recombinant alternative is long overdue. Unfortunately, anti-D monoclonal antibodies have been, at best, disappointing. To determine the primary attribute defining an optimal antibody, we assessed suppression of murine red blood cell (RBC) immunization by single-monoclonal antibodies vs defined blends of subtype-matched antibodies. Allogeneic RBCs expressing the HOD antigen (hen egg lysozyme [HEL]-ovalbumin-human transmembrane Duffy(b)) were transfused into naïve mice alone or together with selected combinations of HEL-specific antibodies, and the resulting suppressive effect was assessed by evaluating the antibody response. Polyclonal HEL antibodies dramatically inhibited the antibody response to the HOD antigen, whereas single-monoclonal HEL antibodies were less effective despite the use of saturating doses. A blend of monoclonal HEL-specific antibodies reactive with different HEL epitopes significantly increased the suppressive effect, whereas a blend of monoclonal antibodies that block each other's binding to the HEL protein did not increase suppression. In conclusion, these data show that polyclonal antibodies are superior to monoclonal antibodies at suppressing the immune response to the HOD cells, a feature that can be completely recapitulated using monoclonal antibodies to different epitopes. © 2016 by The American Society of Hematology.

  18. Study of blood group B antigen with a specific monoclonal antibody (anti-B, b-183).

    PubMed Central

    Rouger, P; Edelman, L; Doinel, C; Reviron, J; Salmon, C; Bach, J F

    1983-01-01

    A murine anti-B monoclonal antibody was obtained by the hybridoma technique. This antibody called anti-B (b-183) is of IgM nature; it is capable of agglutinating normal B, B3, Bx, cis AB and some acquired B red cells. Its association constant is 1.1 X 10(8) l/mol, and appears high compared to those of the monoclonal anti-A. This monoclonal anti-B was used to determine the number of B sites on B3 and Bx red cells. PMID:6840810

  19. Peptide probes derived from pertuzumab by molecular dynamics modeling for HER2 positive tumor imaging.

    PubMed

    Yang, Xiaoliang; Wang, Zihua; Xiang, Zhichu; Li, Dan; Hu, Zhiyuan; Cui, Wei; Geng, Lingling; Fang, Qiaojun

    2017-04-01

    A high level of HER2 expression in breast cancer correlates with a higher tumor growth rate, high metastatic potential, and a poor long-term patient survival rate. Pertuzumab, a human monoclonal antibody, can reduce the effect of HER2 overexpression by preventing HER2 dimerization. In this study, a combination protocol of molecular dynamics modeling and MM/GBSA binding free energy calculations was applied to design peptides that interact with HER2 based on the HER2/pertuzumab crystal structure. Based on a β hairpin in pertuzumab from Glu46 to Lys65-which plays a key role in interacting with HER2-mutations were carried out in silico to improve the binding free energy of the hairpin that interacts with the Phe256-Lys314 of the HER2 protein. Combined the use of one-bead-one-compound library screening, among all the mutations, a peptide (58F63Y) with the lowest binding free energy was confirmed experimentally to have the highest affinity, and it may be used as a new probe in diagnosing and treating HER2-positive breast cancer.

  20. Human Epidermal Growth Factor Receptor 2 (HER-2/neu)-Directed Therapy for Rare Metastatic Epithelial Tumors with HER-2 Amplification

    PubMed Central

    Shin, Daniel Sanghoon; Sherry, Timothy; Kallen, Michael E.; Wong, Steven; Drakaki, Alexandra

    2016-01-01

    Case 1 A 67-year-old Asian female was diagnosed with locally advanced high-grade salivary duct carcinoma in June 2011. Molecular analysis revealed human epidermal growth factor receptor 2 (HER-2) amplification. She received adjuvant therapy with carboplatin/paclitaxel/ trastuzumab and maintenance of trastuzumab. Upon disease progression, trastuzumab could not be continued due to lack of financial coverage. Instead, she was treated with compassionate use of lapatinib from April 2013 and standard 5-fluorouracil. Her disease ultimately progressed and she expired later in 2013. Case 2 A 68-year-old Asian male was diagnosed with extramammary Paget's disease of the scrotum with HER-2 amplification in May 2011. He received 6 cycles of adjuvant trastuzumab/docetaxel/carboplatin followed by maintenance trastuzumab, which was changed to compassionate use of lapatinib as his insurance did not cover further administration of trastuzumab. He showed clinical benefits from single-agent lapatinib and a combination of lapatinib/capecitabine upon progression to the single-agent lapatinib. Ultimately, he was started on ado-trastuzumab emtansine, which was approved at that time by the FDA for HER-2-positive breast cancer progressed on trastuzumab. He is having clinical and radiographic complete response based on current imaging and normalization of his tumor markers. Conclusion HER-2-targeted therapy should be considered for tumors with HER-2 amplification. In our case series, we would like to emphasize this approach in other rare histologies. Specifically, our patient with extramammary Paget's disease of the scrotum represents the first reported case of a non-breast, non-gastric tumor with HER-2 overexpression with complete clinical and radiographic response to HER-2-targeted therapy PMID:27403128

  1. Phase II Study of S-1 plus Trastuzumab for HER2-positive Metastatic Breast Cancer (GBCCSG-01).

    PubMed

    Fujii, Takaaki; Horiguchi, Jun; Yanagita, Yasuhiro; Koibuchi, Yukio; Ikeda, Fumihiro; Uchida, Nobuyuki; Kimura, Morihiko

    2018-02-01

    Treatment strategies for patients with human epidermal growth factor 2 (HER2)-positive metastatic breast cancer (MBC) have significantly progressed. The use of trastuzumab, a monoclonal antibody targeting the HER2 (human epidermal growth factor 2) protein, in combination with chemotherapy improves survival in patients with HER2-positive breast cancer. S-1, an oral combination of fluorouracil derivatives, is widely used in Japan and is more convenient than intravenous drugs. However, little is known about the combination of S-1 and trastuzumab in patients with HER2-positive MBC. We conducted a single-arm, open-label, multicenter prospective phase II study to evaluate the efficacy of an S-1 plus trastuzumab regimen for HER2-positive MBC. S-1 was administered orally [80-120 mg, based on body surface area (BSA)] twice a day for 14 consecutive days in a 3-week cycle. Patients with BSA of <1.25 m 2 received a total of 80 mg of S-1, those with BSA ≥1.5 m 2 received 120 mg, and the remaining received 100 mg daily in two divided doses. Trastuzumab was administered intravenously at 8 mg/kg on day 1 of the first cycle and at 6 mg/kg on day 1 of subsequent cycles, i.e., every 3 weeks. Between December 2008 and March 2013, 10 patients were enrolled and received a median of 17 (range=3-76) cycles of treatment. Overall response and clinical benefit rates were 60.0% and 90.0%, respectively. Progression-free survival was 15.8 (95% confidence interval=9.4-29.6) months and overall survival was 45.5 (95% confidence interval=37.1-62.2) months. Grade 3/4 adverse events included were neutropenia and hyperglycemia in one patient each (10.0%). There was no clinically significant cardiotoxicity. The combination of S-1 and trastuzumab was tolerable and had excellent efficacy with good response and disease control in this study. S-1 plus anti-HER2 therapy is a feasible treatment option for HER2-positive MBC. Copyright© 2018, International Institute of Anticancer Research (Dr. George J

  2. Estimation of Premature Deaths From Lack of Access to Anti-HER2 Therapy for Advanced Breast Cancer in the Brazilian Public Health System.

    PubMed

    Debiasi, Márcio; Reinert, Tomás; Kaliks, Rafael; Amorim, Gilberto; Caleffi, Maira; Sampaio, Carlos; Fernandes, Gustavo Dos Santos; Barrios, Carlos H

    2017-06-01

    Patients with human epidermal growth factor receptor 2 (HER2) -positive metastatic tumors treated in the public health system in Brazil do not have access to trastuzumab. This study aimed to estimate the impact of the lack of access to anti-HER2 therapies on the mortality of these patients. On the basis of published data, the number of patients with HER2-positive advanced breast cancer in 2016 who should receive anti-HER2 targeted therapy was estimated. Three different treatment groups were considered for this hypothetical cohort: chemotherapy alone, chemotherapy plus trastuzumab, and chemotherapy plus trastuzumab and pertuzumab. The number of patients alive after 2 years of follow-up was estimated on the basis of the efficacy results of the pivotal trials considering these interventions. It was calculated that 2,008 women will be diagnosed with advanced HER2-positive breast cancer in Brazil in 2016. It was estimated that only 808 women would be alive in 2018 if they receive only chemotherapy (which is the treatment offered by the public health system). On the other hand, the bar rises to 1,408 women alive in 2018 if they receive chemotherapy plus trastuzumab and 1,576 women alive in 2018 if they receive the gold standard of chemotherapy plus trastuzumab and pertuzumab. Trastuzumab is included in the WHO's list of essential medications, but the Brazilian public health system does not yet provide this treatment to its population with advanced disease. The introduction of trastuzumab and pertuzumab would have a positive effect, preventing premature deaths in women with metastatic HER2-positive breast cancer in Brazil.

  3. Estimation of Premature Deaths From Lack of Access to Anti-HER2 Therapy for Advanced Breast Cancer in the Brazilian Public Health System

    PubMed Central

    Debiasi, Márcio; Reinert, Tomás; Kaliks, Rafael; Amorim, Gilberto; Caleffi, Maira; Sampaio, Carlos; Fernandes, Gustavo dos Santos

    2017-01-01

    Purpose Patients with human epidermal growth factor receptor 2 (HER2) -positive metastatic tumors treated in the public health system in Brazil do not have access to trastuzumab. This study aimed to estimate the impact of the lack of access to anti-HER2 therapies on the mortality of these patients. Methods On the basis of published data, the number of patients with HER2-positive advanced breast cancer in 2016 who should receive anti-HER2 targeted therapy was estimated. Three different treatment groups were considered for this hypothetical cohort: chemotherapy alone, chemotherapy plus trastuzumab, and chemotherapy plus trastuzumab and pertuzumab. The number of patients alive after 2 years of follow-up was estimated on the basis of the efficacy results of the pivotal trials considering these interventions. Results It was calculated that 2,008 women will be diagnosed with advanced HER2-positive breast cancer in Brazil in 2016. It was estimated that only 808 women would be alive in 2018 if they receive only chemotherapy (which is the treatment offered by the public health system). On the other hand, the bar rises to 1,408 women alive in 2018 if they receive chemotherapy plus trastuzumab and 1,576 women alive in 2018 if they receive the gold standard of chemotherapy plus trastuzumab and pertuzumab. Conclusion Trastuzumab is included in the WHO’s list of essential medications, but the Brazilian public health system does not yet provide this treatment to its population with advanced disease. The introduction of trastuzumab and pertuzumab would have a positive effect, preventing premature deaths in women with metastatic HER2-positive breast cancer in Brazil. PMID:28717761

  4. Antibody-Dependent Cell-Mediated Cytotoxicity Effector-Enhanced EphA2 Agonist Monoclonal Antibody Demonstrates Potent Activity against Human Tumors1

    PubMed Central

    Bruckheimer, Elizabeth M; Fazenbaker, Christine A; Gallagher, Sandra; Mulgrew, Kathy; Fuhrmann, Stacy; Coffman, Karen T; Walsh, William; Ready, Shannon; Cook, Kim; Damschroder, Melissa; Kinch, Michael; Kiener, Peter A; Woods, Rob; Gao, Changshou; Dall'Acqua, William; Wu, Herren; Coats, Steven

    2009-01-01

    EphA2 is a receptor tyrosine kinase that has been shown to be overexpressed in a variety of human tumor types. Previous studies demonstrated that agonist monoclonal antibodies targeting EphA2 induced the internalization and degradation of the receptor, thereby abolishing its oncogenic effects. In this study, the in vitro and in vivo antibody-dependent cell-mediated cytotoxicity (ADCC) activity of EphA2 effector-enhanced agonist monoclonal antibodies was evaluated. With tumor cell lines and healthy human peripheral blood monocytes, the EphA2 antibodies demonstrated ∼80% tumor cell killing. In a dose-dependent manner, natural killer (NK) cells were required for the in vitro ADCC activity and became activated as demonstrated by the induction of cell surface expression of CD107a. To assess the role of NK cells on antitumor efficacy in vivo, the EphA2 antibodies were evaluated in xenograft models in severe compromised immunodeficient (SCID) mice (which have functional NK cells and monocytes) and SCID nonobese diabetic (NOD) mice (which largely lack functional NK cells and monocytes). Dosing of EphA2 antibody in the SCID murine tumor model resulted in a 6.2-fold reduction in tumor volume, whereas the SCID/nonobese diabetic model showed a 1.6-fold reduction over the isotype controls. Together, these results demonstrate that the anti-EphA2 monoclonal antibodies may function through at least two mechanisms of action: EphA2 receptor activation and ADCC-mediated activity. These novel EphA2 monoclonal antibodies provide additional means by which host effector mechanisms can be activated for selective destruction of EphA2-expressing tumor cells. PMID:19484140

  5. HER2-positive male breast cancer: an update

    PubMed Central

    Ottini, Laura; Capalbo, Carlo; Rizzolo, Piera; Silvestri, Valentina; Bronte, Giuseppe; Rizzo, Sergio; Russo, Antonio

    2010-01-01

    Although rare, male breast cancer (MBC) remains a substantial cause for morbidity and mortality in men. Based on age frequency distribution, age-specific incidence rate pattern, and prognostic factor profiles, MBC is considered similar to postmenopausal breast cancer (BC). Compared with female BC (FBC), MBC cases are more often hormonal receptor (estrogen receptor/progesterone receptor [ER/PR]) positive and human epidermal growth factor receptor 2 (HER2) negative. Treatment of MBC patients follows the same indications as female postmenopausal with surgery, systemic therapy, and radiotherapy. To date, ER/PR and HER2 status provides baseline predictive information used in selecting optimal adjuvant/neoadjuvant therapy and in the selection of therapy for recurrent or metastatic disease. HER2 represents a very interesting molecular target and a number of compounds (trastuzumab [Herceptin®; F. Hoffmann-La Roche, Basel, Switzerland] and lapatinib [Tykerb®, GlaxoSmithKline, London, UK]) are currently under clinical evaluation. Particularly, trastuzumab, a monoclonal antibody which selectively binds the extracellular domain of HER2, has become an important therapeutic agent for women with HER2-positive (HER2+) BC. Currently, data regarding the use of trastuzumab in MBC patients is limited and only few case reports exist. In all cases, MBC patients received trastuzumab concomitantly with other drugs and no severe toxicity above grade 3 was observed. However, MBC patients that would be candidate for trastuzumab therapy (ie, HER2+/ER+ or HER2+/ER− MBCs) represent only a very small percentage of MBC cases. This is noteworthy, when taking into account that trastuzumab is an important and expensive component of systemic BC therapy. Since there is no data supporting the fact that response to therapy is different for men or women, we concluded that systemic therapy in MBC should be considered on the same basis as for FBC. Particularly in male patients, trastuzumab should be

  6. Canakinumab: a human anti-IL-1β monoclonal antibody for the treatment of cryopyrin-associated periodic syndromes.

    PubMed

    Church, Leigh D; McDermott, Michael F

    2010-11-01

    The cryopyrin-associated periodic syndromes (CAPS) are a group of rare inherited inflammatory diseases associated with overproduction of IL-1β. Canakinumab, developed by Novartis AG (Basel, Switzerland), is an intravenously or subcutaneously administered, fully human monoclonal antibody that neutralizes the bioactivity of human IL-1β. Canakinumab has promising clinical safety and pharmacokinetic properties, and has demonstrated potential for the treatment of CAPS. Canakinumab was recently granted EU orphan drug status for systemic-onset juvenile idiopathic arthritis, and early clinical trials have established that administration of canakinumab every 2 weeks is both safe and effective. Subcutaneous canakinumab (approved formulation) offers some advantages over the existing IL-1β-blocking treatment, anakinra, which must be injected daily and is often not well tolerated by patients. The long-term safety of all targeted anti-IL-1 therapies in CAPS remains an unanswered question owing to the relatively short clinical experience with these agents; as canakinumab produces sustained IL-1 suppression, vigilance is necessary to diagnose the development of adverse events, especially any associated infections.

  7. Cryo-EM structures elucidate neutralizing mechanisms of anti-chikungunya human monoclonal antibodies with therapeutic activity

    DOE PAGES

    Long, Feng; Fong, Rachel H.; Austin, Stephen K.; ...

    2015-10-26

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes severe acute and chronic disease in humans. Although highly inhibitory murine and human monoclonal antibodies (mAbs) have been generated, the structural basis of their neutralizing activity remains poorly characterized. In this paper, we determined the cryo-EM structures of chikungunya virus-like particles complexed with antibody fragments (Fab) of two highly protective human mAbs, 4J21 and 5M16, that block virus fusion with host membranes. Both mAbs bind primarily to sites within the A and B domains, as well as to the B domain’s β-ribbon connector of the viral glycoprotein E2. The footprints ofmore » these antibodies on the viral surface were consistent with results from loss-of-binding studies using an alanine scanning mutagenesis-based epitope mapping approach. The Fab fragments stabilized the position of the B domain relative to the virus, particularly for the complex with 5M16. Finally, this finding is consistent with a mechanism of neutralization in which anti-CHIKV mAbs that bridge the A and B domains impede movement of the B domain away from the underlying fusion loop on the E1 glycoprotein and therefore block the requisite pH-dependent fusion of viral and host membranes.« less

  8. [The preliminary analysis of the recognition epitopes of anti-HEV monoclonal antibodies on HEV ORF2].

    PubMed

    Xiong, Jun-Hui; Guo, Qing-Shun; Ge, Sheng-Xiang; Gu, Ying; Chen, Yi-Xin; Miao, Ji; Du, Hai-Lian; Shi, Wei-Guo; Zhang, Jun; Xia, Ning-Shao

    2008-06-01

    Western blot, capture-PCR, blocking ELISA and synthetic polypeptides were used to systematically study the recognition epitopes on HEV ORF2 of 23 anti-HEV monoclonal antibodies(McAbs) which were previously generated in our laboratory directed against HEV ORF2. Results showed that seven McAbs recognized linear epitopes that located at aa408-458 of HEV ORF2 and 16 conformation-dependent McAbs, most of which recognized the surface epitopes of native HEV, located at aa459-606 of HEV ORF2. The systematical study of the recognition epitopes of anti-HEV McAbs on HEV ORF2 provides important information for the investigation of virus receptor and HEV infection mechanism, as well as its vaccine and diagnostics development.

  9. Monoclonal antibodies against human angiotensinogen, their characterization and use in an angiotensinogen enzyme linked immunosorbent assay.

    PubMed

    Rubin, I; Lykkegaard, S; Olsen, A A; Selmer, J; Ballegaard, M

    1988-01-01

    Monoclonal antibodies were produced against human angiotensinogen. An enzyme linked immunosorbent assay (ELISA) was developed using a high affinity monoclonal antibody as catching antibody and a polyclonal rabbit anti human angiotensinogen antibody as detecting antibody in a "sandwich" ELISA. Linear range of the ELISA was 15-450 pmol/l of human angiotensinogen. Intra- and inter- assay variation coefficients were in the range of 2% to 8%. A correlation coefficient, r = 0.97, (n = 20), with values obtained by radioimmunoassay. This correlation coefficient, obtained by using both normal and pregnant sera, confirmed that the ELISA fulfill the requirements for clinical useful assay. Characterization of the antibodies were performed with respect to affinity constant and epitopes.

  10. A Unique Report: Development of Super Anti-Human IgG Monoclone with Optical Density Over Than 3

    PubMed Central

    Aghebati Maleki, Leili; Baradaran, Behzad; Abdolalizadeh, Jalal; Ezzatifar, Fatemeh; Majidi, Jafar

    2013-01-01

    Purpose: Monoclonal antibodies and related conjugates are key reagents used in biomedical researches as well as, in treatment, purification and diagnosis of infectious and non- infectious diseases. Methods: Balb/c mice were immunized with purified human IgG. Spleen cells of the most immune mouse were fused with SP2/0 in the presence of Poly Ethylene Glycol (PEG). Supernatant of hybridoma cells was screened for detection of antibody by ELISA. Then, the sample was assessed for cross-reactivity with IgM & IgA by ELISA and confirmed by immunoblotting. The subclasses of the selected mAbs were determined. The best clone was injected intraperitoneally to some pristane-injected mice. Anti-IgG mAb was purified from the animals' ascitic fluid by Ion exchange chromatography and then, mAb was conjugated with HRP. Results: In the present study, over than 50 clones were obtained that 1 clone had optical density over than 3. We named this clone as supermonoclone which was selected for limiting dilution. The result of the immunoblotting, showed sharp band in IgG position and did not show any band in IgM&IgA position. Conclusion: Based on the findings of this study, the conjugated monoclonal antibody could have application in diagnosis of infectious diseases like Toxoplasmosis, Rubella and IgG class of other infectious and non- infectious diseases. PMID:24312857

  11. Targeting Sirna Missiles to Her2+ Breast Cancer

    DTIC Science & Technology

    2008-06-01

    intact and appears to be protected from serum nucleases (Fig. 1) . T7 -transcribed siRNA induces higher breast cancer cell cytotoxicity than synthetic...cytotoxicity of T7 transcribed vs s y n t h e t i c anti-HER2 siRNA on HER2+ cells. We acquired a 21 nucleotide (nt) s y n t h e t i c anti-HER2...ErbB2) siRNA and also produced a T7 -transcribed molecule (Silencer Principal Investigator: Medina-Kauwe, Lali K. 2 siRNA construction kit; Ambion) using

  12. Melatonin Represses Metastasis in Her2-postive Human Breast Cancer Cells by Suppressing RSK2 Expression

    PubMed Central

    Mao, Lulu; Summers, Whitney; Xiang, Shulin; Yuan, Lin; Dauchy, Robert T.; Reynolds, Amberly; Wren-Dail, Melissa A.; Pointer, David; Frasch, Tripp; Blask, David E.; Hill, Steven M.

    2016-01-01

    The importance of the circadian/melatonin signal in suppressing the metastatic progression of breast and other cancers has been reported by numerous laboratories including our own. Currently, the mechanisms underlying the anti-metastatic actions of melatonin have not been well established. In the present study, the anti-metastatic actions of melatonin were evaluated and compared on the ERα-negative, Her2-positive SKBR-3 breast tumor cell line and ERα-positive MCF-7 cells overexpressing a constitutively active HER2.1 construct (MCF-7Her2.1 cells). Activation of Her2 is reported to induce the expression and/or phosphorylation-dependent activation of numerous kinases and transcription factors that drive drug resistance and metastasis in breast cancer. A key signaling node activated by the Her2/Mapk/Erk pathway is Rsk2, which has been shown to induce numerous signaling pathways associated with the development of epithelial-to-mesenchymal transition (EMT) and metastasis including: Creb, Stat3, cSrc, Fak, Pax, Fascin, and actin polymerization. The data demonstrate that melatonin (both endogenous and exogenous) significantly represses this invasive/metastatic phenotype through a mechanism that involves the suppression of EMT, either by promoting mesenchymal-to-epithelial transition (MET), and/or by inhibiting key signaling pathways involved in later stages of metastasis. These data, combined with our earlier in vitro studies, support the concept that maintenance of elevated and extended duration of nocturnal melatonin levels plays a critical role in repressing the metastatic progression of breast cancer. PMID:27535706

  13. Large Scale Generation and Characterization of Anti-Human CD34 Monoclonal Antibody in Ascetic Fluid of Balb/c Mice

    PubMed Central

    Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Abdolalizadeh, Jalal; Kazemi, Tohid; Aghebati Maleki, Ali; Sineh sepehr, Koushan

    2013-01-01

    Purpose: Monoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells. Methods: For large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. 5 ml ascitic fluid was harvested from each mouse in two times. Evaluation of mAb titration was assessed by ELISA method. The ascitic fluid was examined for class and subclasses by ELISA mouse mAb isotyping Kit. mAb was purified from ascitic fluid by affinity chromatography on Protein A-Sepharose. Purity of monoclonal antibody was monitored by SDS -PAGE and the purified monoclonal antibody was conjugated with FITC. Results: Monoclonal antibodies with high specificity and sensitivity against human CD34 by hybridoma technology were prepared. The subclass of antibody was IgG1 and its light chain was kappa. Conclusion: The conjugated monoclonal antibody could be a useful tool for isolation, purification and characterization of human hematopoietic stem cells. PMID:24312838

  14. Renal toxicity of anticancer agents targeting HER2 and EGFR.

    PubMed

    Cosmai, Laura; Gallieni, Maurizio; Porta, Camillo

    2015-12-01

    EGFR and HER2 are found overexpressed and/or activated in many different human malignancies (e.g. breast and colon cancer), and a number of drugs specifically targeting these two tyrosine kinases have been developed over the years as anticancer agents. In the present review, the renal safety profile of presently available agents targeting either HER2 or EGFR will be discussed, together with the peculiarities related to their clinical use in patients with impaired renal function, or even in dialysis. Indeed, even though renal toxicity is not so common with these agents, it may nevertheless happen, especially when these agents are combined with traditional chemotherapeutic agents. As a whole, kidney impairment or dialysis should not be regarded per se as reasons not to administer or to stop an active anti-HER or anti-EGFR anticancer treatment, especially given the possibility of significantly improving the life expectancy of many cancer patients with the use of these agents.

  15. Application of four anti-human interferon-alpha monoclonal antibodies for immunoassay and comparative analysis of natural interferon-alpha mixtures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Andersson, G.; Lundgren, E.; Ekre, H.P.

    Four different mouse monoclonal antibodies to human interferon-alpha (IFN-alpha) were evaluated for application in quantitative and comparative analysis of natural IFN-alpha mixtures. Binding to IFN-alpha subtypes in solution revealed individual reactivity patterns. These patterns changed if the IFN-alpha molecules were immobilized either passively to a surface or bound by another antibody. Also, substitution of a single amino acid in IFN-alpha 2 affected the binding, apparently by altering the conformation. Isoelectric focusing of three natural IFN-alpha preparations from different sources, followed by immunoblotting, resulted in individual patterns with each of the four mAbs and also demonstrated variation in the composition ofmore » the IFN-alpha preparations. None of the mAbs was subtype specific, but by combining the different mAbs, and also applying polyclonal anti-human IFN-alpha antibodies, it was possible to design sensitive sandwich ELISAs with broad or more limited IFN-alpha subtype specificity.« less

  16. Monoclonal antibodies to human vitamin D-binding protein.

    PubMed Central

    Pierce, E A; Dame, M C; Bouillon, R; Van Baelen, H; DeLuca, H F

    1985-01-01

    Monoclonal antibodies to vitamin D-binding protein isolated from human serum have been produced. The antibodies obtained have been shown to be specific for human vitamin D-binding protein by three independent assays. The antibodies recognize human vitamin D-binding protein specifically in an enzyme-linked immunosorbent assay. Human vitamin D-binding protein is detected specifically in both pure and crude samples by a radiometric immunosorbent assay (RISA) and by an immunoprecipitation assay. The anti-human vitamin D-binding protein antibodies cross-react with monkey and pig vitamin D-binding protein, but not with vitamin D-binding protein from rat, mouse, or chicken, as determined by the RISA and immunoprecipitation assays. Images PMID:3936035

  17. The Therapeutic Effect of Anti-HER2/neu Antibody Depends on Both Innate and Adaptive Immunity

    PubMed Central

    Park, SaeGwang; Jiang, Zhujun; Mortenson, Eric D.; Deng, Liufu; Radkevich-Brown, Olga; Yang, Xuanming; Sattar, Husain; Wang, Yang; Brown, Nicholas K.; Greene, Mark; Liu, Yang; Tang, Jie; Wang, Shengdian; Fu, Yang-Xin

    2010-01-01

    SUMMARY Anti-HER2/neu antibody therapy is reported to mediate tumor regression by interrupting oncogenic signals and/or inducing FcR-mediated cytotoxicity. Here, we demonstrate that the mechanisms of tumor regression by this therapy also require the adaptive immune response. Activation of innate immunity and T cells, initiated by antibody treatment, was necessary. Intriguingly, the addition of chemotherapeutic drugs, while capable of enhancing the reduction of tumor burden, could abrogate antibody-initiated immunity leading to decreased resistance to re-challenge or earlier relapse. Increased influx of both innate and adaptive immune cells into the tumor microenvironment by a selected immunotherapy further enhanced subsequent antibody-induced immunity, leading to increased tumor eradication and resistance to re-challenge. Therefore, this study proposes a model and strategy for anti-HER2/neu antibody-mediated tumor clearance. PMID:20708157

  18. LJM716 in Japanese patients with head and neck squamous cell carcinoma or HER2-overexpressing breast or gastric cancer.

    PubMed

    Takahashi, Shunji; Kobayashi, Takayuki; Tomomatsu, Junichi; Ito, Yoshinori; Oda, Hisanobu; Kajitani, Tatsuhiro; Kakizume, Tomoyuki; Tajima, Takeshi; Takeuchi, Hiromi; Maacke, Heiko; Esaki, Taito

    2017-01-01

    Human epidermal growth factor receptor 3 (HER3) has been identified as an important component of many receptor tyrosine kinase-driven cancers. LJM716 is a human IgG monoclonal antibody that binds HER3, trapping it in an inactive conformation. In this study, a phase I dose escalation was performed with a primary objective to establish the maximum tolerated dose and/or the recommended dose of LJM716 in Japanese patients with selected advanced solid tumors. Secondary objectives included the evaluation of the safety and tolerability, preliminary antitumor activity, and pharmacokinetics of LJM716 in Japanese patients. LJM716 was administered intravenously at doses of 10, 20, or 40 mg/kg once weekly, in 28-day cycles, to 12 patients with HER2-amplified breast cancer or gastric cancer, or with esophageal squamous cell carcinoma or squamous cell carcinoma of the head and neck, regardless of HER2 status. The maximum tolerated dose was not reached, and the recommended dose was established at 40 mg/kg. No dose-limiting toxicities were observed in the first cycle. The most frequently reported adverse events were diarrhea, fatigue, stomatitis, pyrexia, and paronychia. One unconfirmed partial response was observed in a patient with breast cancer, and 50% of the patients achieved stable disease as the best overall response. Exposure increased with ascending dose, and half-life was estimated to be 11-14 days. No anti-LJM716 antibodies were detected. LJM716 was well tolerated in Japanese patients, and a degree of tumor shrinkage was observed. ClinicalTrials.gov NCT01911936.

  19. CTLs directed against HER2 specifically cross-react with HER3 and HER4.

    PubMed

    Conrad, Heinke; Gebhard, Kerstin; Krönig, Holger; Neudorfer, Julia; Busch, Dirk H; Peschel, Christian; Bernhard, Helga

    2008-06-15

    The human epidermal growth factor receptor 2 (HER2) has been targeted as a breast cancer-associated Ag by T cell-based immunotherapeutical strategies such as cancer vaccines and adoptive T cell transfer. The prerequisite for a successful T cell-based therapy is the induction of T cells capable of recognizing the HER2-expressing tumor cells. In this study, we generated human cytotoxic T cell clones directed against the HER2(369-377) epitope known to be naturally presented with HLA-A*0201. Those HER2-reactive CTLs, which were also tumor lytic, exhibited a similar lysis pattern dividing the targets in lysable and nonlysable tumor cells. Several HER2-expressing tumor cells became susceptible to CTL-mediated lysis after IFN-gamma treatment and, in parallel, up-regulated molecules of the Ag-presenting machinery, indicating that the tumor itself also contributes to the success of CTL-mediated killing. Some of the HER2(369-377)-reactive T cells specifically cross-reacted with the corresponding peptides derived from the family members HER3 and/or HER4 due to a high sequence homology. The epitopes HER3(356-364) and HER4(361-369) were endogenously processed and contributed to the susceptibility of cell lysis by HER cross-reacting CTLs. The principle of "double" or "triple targeting" the HER Ags by cross-reacting T cells will impact the further development of T cell-based therapies.

  20. Advantages and disadvantages of technologies for HER2 testing in breast cancer specimens.

    PubMed

    Furrer, Daniela; Sanschagrin, François; Jacob, Simon; Diorio, Caroline

    2015-11-01

    Human epidermal growth factor receptor 2 (HER2) plays a central role as a prognostic and predictive marker in breast cancer specimens. Reliable HER2 evaluation is central to determine the eligibility of patients with breast cancer to targeted anti-HER2 therapies such as trastuzumab and lapatinib. Presently, several methods exist for the determination of HER2 status at different levels (protein, RNA, and DNA level). In this review, we discuss the main advantages and disadvantages of the techniques developed so far for the evaluation of HER2 status in breast cancer specimens. Each technique has its own advantages and disadvantages. It is therefore not surprising that no consensus has been reached so far on which technique is the best for the determination of HER2 status. Currently, emphasis must be put on standardization of procedures, internal and external quality control assessment, and competency evaluation of already existing methods to ensure accurate, reliable, and clinically meaningful test results. Development of new robust and accurate diagnostic assays should also be encouraged. In addition, large clinical trials are warranted to identify the technique that most reliably predicts a positive response to anti-HER2 drugs. Copyright© by the American Society for Clinical Pathology.

  1. Is the skin a sanctuary for breast cancer cells during treatment with anti-HER2 antibodies?

    PubMed

    Graziano, Vincenzo; Scognamiglio, Maria Teresa; Zilli, Marinella; Giampietro, Jamara; Vici, Patrizia; Natoli, Clara; Grassadonia, Antonino

    2015-01-01

    The occurrence of skin metastases is a common event in patients affected by advanced breast cancer, usually associated with systemic disease progression. Here we describe 2 cases of diffuse cutaneous metastases from HER2-overexpressing breast cancer occurring despite a dramatic response in liver and bone, respectively, during treatment with anti-HER2 antibodies Trastuzumab and Pertuzumab. We discuss the reasons for this discrepancy and suggest a possible implication of impaired immune response in the skin. Future research should provide strategies to overcome the induction of immune privilege in the skin in order to avoid discontinuation of effective treatments.

  2. Isolation of breast cancer and gastric cancer circulating tumor cells by use of an anti HER2-based microfluidic device.

    PubMed

    Galletti, Giuseppe; Sung, Matthew S; Vahdat, Linda T; Shah, Manish A; Santana, Steven M; Altavilla, Giuseppe; Kirby, Brian J; Giannakakou, Paraskevi

    2014-01-07

    Circulating tumor cells (CTCs) have emerged as a reliable source of tumor cells, and their concentration has prognostic implications. CTC capture offers real-time access to cancer tissue without the need of an invasive biopsy, while their phenotypic and molecular interrogation can provide insight into the biological changes of the tumor that occur during treatment. The majority of the CTC capture methods are based on EpCAM expression as a surface marker of tumor-derived cells. However, EpCAM protein expression levels can be significantly down regulated during cancer progression as a consequence of the process of epithelial to mesenchymal transition. In this paper, we describe a novel HER2 (Human Epidermal Receptor 2)-based microfluidic device for the isolation of CTCs from peripheral blood of patients with HER2-expressing solid tumors. We selected HER2 as an alternative to EpCAM as the receptor is biologically and therapeutically relevant in several solid tumors, like breast cancer (BC), where it is overexpressed in 30% of the patients and expressed in 90%, and gastric cancer (GC), in which HER2 presence is identified in more than 60% of the cases. We tested the performance of various anti HER2 antibodies in a panel of nine different BC cell lines with varying HER2 protein expression levels, using immunoblotting, confocal microscopy, live cells imaging and flow cytometry analyses. The antibody associated with the highest capture efficiency and sensitivity for HER2 expressing cells on the microfluidic device was the one that performed best in live cells imaging and flow cytometry assays as opposed to the fixed cell analyses, suggesting that recognition of the native conformation of the HER2 extracellular epitope on living cells was essential for specificity and sensitivity of CTC capture. Next, we tested the performance of the HER2 microfluidic device using blood from metastatic breast and gastric cancer patients. The HER2 microfluidic device exhibited CTC capture

  3. Targeting the human epidermal growth factor receptor 2 (HER2) oncogene in colorectal cancer

    PubMed Central

    Siena, S; Sartore-Bianchi, A; Marsoni, S; Hurwitz, H I; McCall, S J; Penault-Llorca, F; Srock, S; Bardelli, A; Trusolino, L

    2018-01-01

    Abstract Human epidermal growth factor receptor 2 (HER2) is an oncogenic driver, and a well-established therapeutic target in breast and gastric cancers. Using functional and genomic analyses of patient-derived xenografts, we previously showed that a subset (approximately 5%) of metastatic colorectal cancer (CRC) tumors is driven by amplification or mutation of HER2. This paper reviews the role of HER2 amplification as an oncogenic driver, a prognostic and predictive biomarker, and a clinically actionable target in CRC, considering the specifics of HER2 testing in this tumor type. While the role of HER2 as a biomarker for prognosis in CRC remains uncertain, its relevance as a therapeutic target has been established. Indeed, independent studies documented substantial clinical benefit in patients treated with biomarker-driven HER2-targeted therapies, with an impact on response rates and duration of response that compared favorably with immunotherapy and other examples of precision oncology. HER2-targeted therapeutic strategies have the potential to change the treatment paradigm for a clinically relevant subgroup of metastatic CRC patients. PMID:29659677

  4. The chemiluminescent response of human monocytes to red cells sensitized with monoclonal anti-Rh(D) antibodies.

    PubMed

    Hadley, A G; Kumpel, B M; Merry, A H

    1988-01-01

    Luminol-enhanced chemiluminescence (CL) was used to assess the metabolic response of human monocytes to red cells sensitized with known amounts of anti-Rh(D). Monoclonal antibodies were used to facilitate a comparison between the functional activities of IgG1 and IgG3 subclasses. The detection of CL provided a simple, rapid and semi-quantitative means of measuring monocyte response to sensitized red cells (IgG-RBC). Monocyte response to IgG3-RBC was quantitatively greater, more rapid and less susceptible to inhibition by fluid phase IgG than monocyte response to IgG1-RBC. The minimum levels of sensitization required to elicit CL from monocytes were approximately 2500 IgG3 molecules per red cell, or approximately 5000 IgG1 molecules per cell.

  5. An immunogen synthesis strategy for the development of specific anti-deoxynivalenol monoclonal antibodies.

    PubMed

    Sanders, Melanie; Guo, Yirong; Iyer, Abhishek; García, Yara Ruiz; Galvita, Anastasia; Heyerick, Arne; Deforce, Dieter; Risseeuw, Martijn D P; Van Calenbergh, Serge; Bracke, Marc; Eremin, Sergei; Madder, Annemieke; De Saeger, Sarah

    2014-01-01

    An immunogen synthesis strategy was designed to develop anti-deoxynivalenol (DON) monoclonal antibodies with low cross-reactivity against structurally similar trichothecenes. A total of eight different DON immunogens were synthesised, differing in the type and position of the linker on the DON molecule. After immunisation, antisera from mice immunised with different DON immunogens were checked for the presence of relevant antibodies. Then, both homologous and heterologous enzyme-linked immunosorbent assays (ELISAs) were performed for hybridoma screening. Finally, three monoclonal antibodies against DON and its analogues were generated. In addition, monoclonal antibody 13H1 could recognise DON and its analogues in the order of HT-2 toxin > 15-acetyldeoxynivalenol (15-ADON) > DON, with IC₅₀ ranging from 1.14 to 2.13 µg ml⁻¹. Another monoclonal antibody 10H10 manifested relatively close sensitivities to DON, 3-acetyldeoxynivalenol (3-ADON) and 15-ADON, with IC₅₀ values of 22, 15 and 34 ng ml⁻¹, respectively. Using an indirect ELISA format decreases the 10H10 sensitivity to 15-ADON with 92%. A third monoclonal antibody 2A9 showed to be very specific and sensitive to 3-ADON, with IC₅₀ of 0.38 ng ml⁻¹. Using both 2A9 and 10H10 monoclonal antibodies allows determining sole DON contamination.

  6. EV20-Sap, a novel anti-HER-3 antibody-drug conjugate, displays promising antitumor activity in melanoma

    PubMed Central

    Ponziani, Sara; Lamolinara, Alessia; Iezzi, Manuela; Cimini, Annamaria; Angelucci, Francesco; Sorda, Rossana La; Laurenzi, Vincenzo De; Natali, Pier Giorgio; Ippoliti, Rodolfo; Iacobelli, Stefano; Sala, Gianluca

    2017-01-01

    Melanoma is the most biologically aggressive skin cancer of well established constitutive and induced resistance to pharmacological treatment. Despite the recent progresses in immunotherapies, many advanced metastatic melanoma patients still face a significant mortality risk. The aggressive nature of this disease sustains an urgent need for more successful, effective drugs. HER-3 - one of the four member of the tyrosin kinase epidermal growth factor receptors (EGFRs) family- is frequently overexpressed in solid tumors, including melanoma. Moreover, up-regulation of HER-3 and its ligand NRGβ-1 are associated with poor prognosis, thus suggesting this receptor as a suitable target for cancer therapy. Several monoclonal antibodies targeting HER-3 are currently available, but preliminary results from clinical testing of these agents reveal a modest efficacy. Thus, a substantial improvement over this immunotherapeutic approach could be offered by an anti-HER-3 based Antibody-Drug Conjugate (ADC). In the present paper, we describe the generation of an ADC obtained by coupling the HER-3 targeting antibody EV20 linked to the plant toxin Saporin (Sap). In vitro, this ADC displays a powerful, specific and target-dependent cytotoxic activity which correlates with the degree of expression and internalization of HER-3 on tumor cells. Furthermore, in a murine melanoma model, EV20-Sap treatment leads to a significant reduction of the number of pulmonary metastasis. PMID:29221137

  7. Human Epidermal Growth Factor Receptor 2 (HER2) -Specific Chimeric Antigen Receptor-Modified T Cells for the Immunotherapy of HER2-Positive Sarcoma.

    PubMed

    Ahmed, Nabil; Brawley, Vita S; Hegde, Meenakshi; Robertson, Catherine; Ghazi, Alexia; Gerken, Claudia; Liu, Enli; Dakhova, Olga; Ashoori, Aidin; Corder, Amanda; Gray, Tara; Wu, Meng-Fen; Liu, Hao; Hicks, John; Rainusso, Nino; Dotti, Gianpietro; Mei, Zhuyong; Grilley, Bambi; Gee, Adrian; Rooney, Cliona M; Brenner, Malcolm K; Heslop, Helen E; Wels, Winfried S; Wang, Lisa L; Anderson, Peter; Gottschalk, Stephen

    2015-05-20

    The outcome for patients with metastatic or recurrent sarcoma remains poor. Adoptive therapy with tumor-directed T cells is an attractive therapeutic option but has never been evaluated in sarcoma. We conducted a phase I/II clinical study in which patients with recurrent/refractory human epidermal growth factor receptor 2 (HER2) -positive sarcoma received escalating doses (1 × 10(4)/m(2) to 1 × 10(8)/m(2)) of T cells expressing an HER2-specific chimeric antigen receptor with a CD28.ζ signaling domain (HER2-CAR T cells). We enrolled 19 patients with HER2-positive tumors (16 osteosarcomas, one Ewing sarcoma, one primitive neuroectodermal tumor, and one desmoplastic small round cell tumor). HER2-CAR T-cell infusions were well tolerated with no dose-limiting toxicity. At dose level 3 (1 × 10(5)/m(2)) and above, we detected HER2-CAR T cells 3 hours after infusion by quantitative polymerase chain reaction in 14 of 16 patients. HER2-CAR T cells persisted for at least 6 weeks in seven of the nine evaluable patients who received greater than 1 × 10(6)/m(2) HER2-CAR T cells (P = .005). HER2-CAR T cells were detected at tumor sites of two of two patients examined. Of 17 evaluable patients, four had stable disease for 12 weeks to 14 months. Three of these patients had their tumor removed, with one showing ≥ 90% necrosis. The median overall survival of all 19 infused patients was 10.3 months (range, 5.1 to 29.1 months). This first evaluation of the safety and efficacy of HER2-CAR T cells in patients with cancer shows the cells can persist for 6 weeks without evident toxicities, setting the stage for studies that combine HER2-CAR T cells with other immunomodulatory approaches to enhance their expansion and persistence. © 2015 by American Society of Clinical Oncology.

  8. Fully-human Monoclonal Antibodies Against Human EphrinB2 and EphB4 | NCI Technology Transfer Center | TTC

    Cancer.gov

    The National Cancer Institute's Cancer and Inflammation Program is seeking statements of capability or interest from parties interested in licensing fully-human monoclonal antibodies against human EphrinB2 and EphB4.

  9. Large Scale Generation and Characterization of Anti-Human IgA Monoclonal Antibody in Ascitic Fluid of Balb/c Mice

    PubMed Central

    Ezzatifar, Fatemeh; Majidi, Jafar; Baradaran, Behzad; Aghebati Maleki, Leili; Abdolalizadeh, Jalal; Yousefi, Mehdi

    2015-01-01

    Purpose: Monoclonal antibodies are potentially powerful tools used in biomedical research, diagnosis, and treatment of infectious diseases and cancers. The monoclonal antibody against Human IgA can be used as a diagnostic application to detect infectious diseases. The aim of this study was to improve an appropriate protocol for large-scale production of mAbs against IgA. Methods: For large-scale production of the monoclonal antibody, hybridoma cells that produce monoclonal antibodies against Human IgA were injected intraperitoneally into Balb/c mice that were previously primed with 0.5 ml Pristane. After ten days, ascitic fluid was harvested from the peritoneum of each mouse. The ELISA method was carried out for evaluation of the titration of produced mAbs. The ascitic fluid was investigated in terms of class and subclass by a mouse mAb isotyping kit. MAb was purified from the ascitic fluid by ion exchange chromatography. The purity of the monoclonal antibody was confirmed by SDS-PAGE, and the purified monoclonal antibody was conjugated with HRP. Results: Monoclonal antibodies with high specificity and sensitivity against Human IgA were prepared by hybridoma technology. The subclass of antibody was IgG1 and its light chain was the kappa type. Conclusion: This conjugated monoclonal antibody could have applications in designing ELISA kits in order to diagnose different infectious diseases such as toxoplasmosis and H. Pylori. PMID:25789225

  10. Anti-Semaphorin 3A neutralization monoclonal antibody prevents sepsis development in lipopolysaccharide-treated mice.

    PubMed

    Yamashita, Naoya; Jitsuki-Takahashi, Aoi; Ogawara, Miyuki; Ohkubo, Wataru; Araki, Tomomi; Hotta, Chie; Tamura, Tomohiko; Hashimoto, Shu-ichi; Yabuki, Takashi; Tsuji, Toru; Sasakura, Yukie; Okumura, Hiromi; Takaiwa, Aki; Koyama, Chika; Murakami, Koji; Goshima, Yoshio

    2015-09-01

    Semaphorin 3A (Sema3A), originally identified as a potent growth cone collapsing factor in developing sensory neurons, is now recognized as a key player in immune, cardiovascular, bone metabolism and neurological systems. Here we established an anti-Sema3A monoclonal antibody that neutralizes the effects of Sema3A both in vitro and in vivo. The anti-Sema3A neutralization chick IgM antibodies were screened by combining an autonomously diversifying library selection system and an in vitro growth cone collapse assay. We further developed function-blocking chick-mouse chimeric and humanized anti-Sema3A antibodies. We found that our anti-Sema3A antibodies were effective for improving the survival rate in lipopolysaccharide-induced sepsis in mice. Our antibody is a potential therapeutic agent that may prevent the onset of or alleviate symptoms of human diseases associated with Sema3A. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Establishment of Anti-Human ATRX Monoclonal Antibody AMab-6

    PubMed Central

    Ogasawara, Satoshi; Fujii, Yuki; Kaneko, Mika K.; Oki, Hiroharu; Sabit, Hemragul; Nakada, Mitsutoshi; Suzuki, Hiroyoshi; Ichimura, Koichi; Komori, Takashi

    2016-01-01

    Gliomas are the most frequently occurring brain tumors with a heterogeneous molecular background. The molecular subgrouping of gliomas more prognostically stratifies patients into distinct groups compared with conventional histological classification. The most important molecules for the subtype diagnosis of diffuse gliomas are mutations of isocitrate dehydrogenase (IDH), TERT promoter, and α-thalassemia/mental-retardation-syndrome-X-linked (ATRX) and the codeletion of 1p/19q. Among them, IDH and ATRX mutations can be diagnosed using specific monoclonal antibodies (mAbs). We have developed many mAbs against IDH mutants, including HMab-1/HMab-2 against IDH1-R132H and multispecific mAbs MsMab-1/MsMab-2 against IDH1/2 mutations. In contrast, highly sensitive mAbs against ATRX remain to be established. In this study, we immunized mice with recombinant human ATRX and developed a novel mAb, AMab-6. The dissociation constant of AMab-6 was determined to be 9.7 × 10−10 M, indicating that the binding affinity of AMab-6 is very high. Furthermore, AMab-6 sensitively detects ATRX in Western blot and immunohistochemical analyses, indicating that AMab-6 could become the standard marker to determine the ATRX mutation status of gliomas in immunohistochemical analyses. PMID:27788029

  12. Establishment of Anti-Human ATRX Monoclonal Antibody AMab-6.

    PubMed

    Ogasawara, Satoshi; Fujii, Yuki; Kaneko, Mika K; Oki, Hiroharu; Sabit, Hemragul; Nakada, Mitsutoshi; Suzuki, Hiroyoshi; Ichimura, Koichi; Komori, Takashi; Kato, Yukinari

    2016-10-01

    Gliomas are the most frequently occurring brain tumors with a heterogeneous molecular background. The molecular subgrouping of gliomas more prognostically stratifies patients into distinct groups compared with conventional histological classification. The most important molecules for the subtype diagnosis of diffuse gliomas are mutations of isocitrate dehydrogenase (IDH), TERT promoter, and α-thalassemia/mental-retardation-syndrome-X-linked (ATRX) and the codeletion of 1p/19q. Among them, IDH and ATRX mutations can be diagnosed using specific monoclonal antibodies (mAbs). We have developed many mAbs against IDH mutants, including HMab-1/HMab-2 against IDH1-R132H and multispecific mAbs MsMab-1/MsMab-2 against IDH1/2 mutations. In contrast, highly sensitive mAbs against ATRX remain to be established. In this study, we immunized mice with recombinant human ATRX and developed a novel mAb, AMab-6. The dissociation constant of AMab-6 was determined to be 9.7 × 10 -10 M, indicating that the binding affinity of AMab-6 is very high. Furthermore, AMab-6 sensitively detects ATRX in Western blot and immunohistochemical analyses, indicating that AMab-6 could become the standard marker to determine the ATRX mutation status of gliomas in immunohistochemical analyses.

  13. Treatment of advanced HER2-positive breast cancer: 2018 and beyond.

    PubMed

    Pondé, Noam; Brandão, Mariana; El-Hachem, Georges; Werbrouck, Emilie; Piccart, Martine

    2018-05-02

    In the 1980s the importance of HER2 signalling to the aberrant behaviour of a subset of breast cancer cells was recognized for the first time and, consequently, a hitherto unknown subtype of breast cancer - HER2-positive (HER2+) breast cancer was identified. The development of the anti-HER2 class of drugs, first with trastuzumab, followed closely by lapatinib, pertuzumab, and T-DM1, has improved outcomes dramatically. Nevertheless, metastatic HER2+ breast cancer remains an incurable disease and new therapeutic options are needed. Additionally, the rapid changes in treatment standards 5 years ago have left unanswered numerous questions, including the "real-life" benefit of pertuzumab and T-DM1, since both the CLEOPATRA and EMILIA trials were conducted in populations that no longer exist in practice and, moreover, on the role of endocrine therapy in HER2+ disease. Furthermore, despite significant research efforts, including translational efforts and new imaging techniques, no predictive biomarkers have been clinically validated and therefore a more refined approach to treatment tailoring remains beyond our reach. Finally, a better understanding of resistance to currently existing anti-HER2 agents and of the role played by the microenvironment (e.g. immune system) and of interconnected signalling pathways (e.g. PI3K-mTOR-AKT) is at the core of clinical trials exploring new drugs and new regimens. These include the combination of anti-HER2 agents and anti-PD-1/PDL-1, PI3K inhibitors and CDK 4/6 inhibitors, as well as a host of new panHER inhibitors, drug antibody conjugates and anti-HER antibodies, which may, in coming years further push the boundaries of what we can do for our patients. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Treatment of metastatic breast cancer: a large observational study on adherence to French prescribing guidelines and financial cost of the anti-HER2 antibody trastuzumab.

    PubMed

    Poncet, Bénédicte; Colin, Cyrille; Bachelot, Thomas; Jaisson-Hot, Isabelle; Derain, Laure; Magaud, Laurent; Fournel-Federico, Cécile; Mousseau, Mireille; Tigaud, Jean-Dominique; Jacquin, Jean-Philippe; Trillet-Lenoir, Véronique

    2009-08-01

    This observational study aimed at analyzing adherence to prescribing guidelines of anti-HER2 monoclonal antibody trastuzumab treatment for metastatic breast cancer. Efficacy and costs were also evaluated. The adherence to the trastuzumab treatment plan was analyzed according to both the French postlicensing guidelines published in 2001 and clinical guidelines from the regional cancer network in a cohort of 131 consecutive patients. The level of appropriateness to the molecular target was very high (92% of the patients showed a positive HER2 status, defined as HER2 3+ confirmed by immunohistochemistry or 2+ confirmed by fluorescent in situ hybridization). The treatment plan was made according to the French postlicensing guidelines in 41 patients (31.3%) and to the regional clinical guidelines for 109 patients (83.2%). The main reason for the difference was the type of molecules authorized for combination to trastuzumab. The median overall survival of the studied population was 18.6 months and the median progression-free survival rate was 7.7 months. Up to death or end of the study, the overall cost for the treatment of breast cancer with trastuzumab per patient and per year was 47,832 euro. This quite low adherence of clinicians to the French postlicensing guidelines is in contrast with the high level of adherence to the regional clinical guidelines. The reason is that the latter are less rigid about previously received treatments and enlarge the potential associated cytotoxics to vinorelbine. This supports the French National Cancer Institute decision to get expert clinicians involved together with the French agency for sanitary security of health products and the high health authority in a common elaboration of guidelines.

  15. Human Monoclonal Antibodies Targeting Glypican-2 in Neuroblastoma | NCI Technology Transfer Center | TTC

    Cancer.gov

    Researchers at the National Cancer Institute’s Laboratory of Molecular Biology (NCI LMB) have developed and isolated several single domain monoclonal human antibodies against GPC2. NCI seeks parties interested in licensing or co-developing GPC2 antibodies and/or conjugates.

  16. The dynamics of HER2 status in esophageal adenocarcinoma.

    PubMed

    Creemers, Aafke; Ebbing, Eva A; Hooijer, Gerrit K J; Stap, Lisanne; Jibodh-Mulder, Rajni A; Gisbertz, Susanne S; van Berge Henegouwen, Mark I; van Montfoort, Maurits L; Hulshof, Maarten C C M; Krishnadath, Kausilia K; van Oijen, Martijn G H; Bijlsma, Maarten F; Meijer, Sybren L; van Laarhoven, Hanneke W M

    2018-06-01

    Trastuzumab, a monoclonal antibody against HER2, has become standard of care for metastatic HER2-overexpressing esophagogastric adenocarcinoma and is currently investigated as (neo)adjuvant treatment option in HER2-positive esophagogastric adenocarcinoma. The HER2 status is commonly determined on archived material of the primary tumor. However, this status may change over the course of treatment or disease progression. The aim of this study was to assess the dynamics of HER2 status in esophageal adenocarcinoma (EAC) in patients with resectable and recurrent disease, and to determine the associations of these changes with clinical outcome. Discordance, defined as any change in HER2 status between matched biopsy and post-neoadjuvant chemoradiation therapy resection specimen ( N = 170), or between matched resection specimen and recurrence of patients not eligible for curative treatment ( N = 61), was determined using the standardized HER2 status scoring system. Clinically relevant positive discordance was defined as a change to HER2 positive status, as this would imply eligibility for HER2-targeted therapy. A difference in HER2 status between biopsy and resection specimen and resection specimen and metachronous recurrence was observed in 2.1% ( n = 3) and 3.3% ( n = 2) of the paired cases, respectively. Clinically relevant discordance was detected in 1.4% ( n = 2) of the resectable patients and 1.6% ( n = 1) of the patients with recurrent disease. Patients with HER2-positive status tumors before start of neoadjuvant treatment showed better overall survival, but not statistically significant. No association between HER2 status discordance and survival was found. Clinically relevant HER2 status discordance was observed and in order to prevent under-treatment of patients, the assessment of HER2 status in the metastatic setting should preferably be performed on the most recently developed lesions if the previous HER2 assessment on archival material of the primary tumor

  17. Preparation of monoclonal antibody of anti-feline calicivirus and establishment of double-antibody sandwich enzyme-linked immunosorbent assay detecting method.

    PubMed

    Yuan, B; Ai, C-X; Yuan, L; Gao, W; Hu, J-P; Chen, J; Ren, W-Z

    2014-09-12

    This study aimed to prepare monoclonal antibody of feline calicivirus (FCV) and identify its basic biological characteristics. Saturated ammonium sulfate precipitation, combined differential centrifugation, and cesium chloride density gradient centrifugation were used for the purification of FCV. The purified FCV was used as antigen to immunize BALB/c mice. The hybridoma lines of anti-FCV monoclonal antibodies were established using cell fusion and hybridoma screening techniques. The subtypes of the monoclonal antibody were identified. The results showed that 3 strains of hybridoma cell lines stably secreted anti-FCV monoclonal antibody; they were named as D8, E5, and H4. The D8 and E5 were IgM subtype antibodies, and H4 was IgG2b subtype antibody. The monoclonal antibody obtained shared no cross-reactivity with feline parvovirus, canine parvovirus, and canine distemper virus. According to the different recognition sites of 2 monoclonal antibodies E5 and H4 to the FCV, they were used to coat microtiter plates and prepare 2 enzyme-labeled secondary antibodies to establish double-antibody sandwich enzyme-linked immunosorbent assay detecting method.

  18. Ta1, a novel 105 KD human T cell activation antigen defined by a monoclonal antibody.

    PubMed

    Fox, D A; Hussey, R E; Fitzgerald, K A; Acuto, O; Poole, C; Palley, L; Daley, J F; Schlossman, S F; Reinherz, E L

    1984-09-01

    By using a murine monoclonal antibody produced against an IL 2-dependent human T cell line, we defined a T lineage-specific molecule, termed Ta1, that is expressed strongly on activated T lymphocytes of both the T4 and T8 subsets, as well as on T cell lines and clones, but only weakly on a fraction of resting T cells. SDS-PAGE analysis of immunoprecipitates from 125I-labeled, activated T cells demonstrates a single major band of apparent m.w. 105 KD under both reducing and nonreducing conditions. Unlike anti-IL 2 receptor antibodies, anti-Ta1 does not inhibit T cell proliferative responses to mitogen, antigen, or IL 2-containing medium. Moreover, anti-Ta1 has no effect on T cell-mediated cytotoxicity. Ta1 appears to be a novel human T cell-specific activation antigen that may serve as a useful marker of T cell activation in human disease.

  19. Human Epidermal Growth Factor Receptor 2 (HER2) –Specific Chimeric Antigen Receptor–Modified T Cells for the Immunotherapy of HER2-Positive Sarcoma

    PubMed Central

    Ahmed, Nabil; Brawley, Vita S.; Hegde, Meenakshi; Robertson, Catherine; Ghazi, Alexia; Gerken, Claudia; Liu, Enli; Dakhova, Olga; Ashoori, Aidin; Corder, Amanda; Gray, Tara; Wu, Meng-Fen; Liu, Hao; Hicks, John; Rainusso, Nino; Dotti, Gianpietro; Mei, Zhuyong; Grilley, Bambi; Gee, Adrian; Rooney, Cliona M.; Brenner, Malcolm K.; Heslop, Helen E.; Wels, Winfried S.; Wang, Lisa L.; Anderson, Peter; Gottschalk, Stephen

    2015-01-01

    Purpose The outcome for patients with metastatic or recurrent sarcoma remains poor. Adoptive therapy with tumor-directed T cells is an attractive therapeutic option but has never been evaluated in sarcoma. Patients and Methods We conducted a phase I/II clinical study in which patients with recurrent/refractory human epidermal growth factor receptor 2 (HER2) –positive sarcoma received escalating doses (1 × 104/m2 to 1 × 108/m2) of T cells expressing an HER2-specific chimeric antigen receptor with a CD28.ζ signaling domain (HER2-CAR T cells). Results We enrolled 19 patients with HER2-positive tumors (16 osteosarcomas, one Ewing sarcoma, one primitive neuroectodermal tumor, and one desmoplastic small round cell tumor). HER2-CAR T-cell infusions were well tolerated with no dose-limiting toxicity. At dose level 3 (1 × 105/m2) and above, we detected HER2-CAR T cells 3 hours after infusion by quantitative polymerase chain reaction in 14 of 16 patients. HER2-CAR T cells persisted for at least 6 weeks in seven of the nine evaluable patients who received greater than 1 × 106/m2 HER2-CAR T cells (P = .005). HER2-CAR T cells were detected at tumor sites of two of two patients examined. Of 17 evaluable patients, four had stable disease for 12 weeks to 14 months. Three of these patients had their tumor removed, with one showing ≥ 90% necrosis. The median overall survival of all 19 infused patients was 10.3 months (range, 5.1 to 29.1 months). Conclusion This first evaluation of the safety and efficacy of HER2-CAR T cells in patients with cancer shows the cells can persist for 6 weeks without evident toxicities, setting the stage for studies that combine HER2-CAR T cells with other immunomodulatory approaches to enhance their expansion and persistence. PMID:25800760

  20. A Recombinant Humanized Anti-Cocaine Monoclonal Antibody Inhibits the Distribution of Cocaine to the Brain in Rats

    PubMed Central

    Gooden, Felicia C. T.; Tabet, Michael R.; Ball, William J.

    2014-01-01

    The monoclonal antibody (mAb), h2E2, is a humanized version of the chimeric human/murine anti-cocaine mAb 2E2. The recombinant h2E2 protein was produced in vitro from a transfected mammalian cell line and retained high affinity (4 nM Kd) and specificity for cocaine over its inactive metabolites benzoylecgonine (BE) and ecgonine methyl ester. In rats, pharmacokinetic studies of h2E2 (120 mg/kg i.v.) showed a long terminal elimination half-life of 9.0 days and a low volume of distribution at steady state (Vdss) of 0.3 l/kg. Pretreatment with h2E2 produced a dramatic 8.8-fold increase in the area under the plasma cocaine concentration-time curve (AUC) and in brain a concomitant decrease of 68% of cocaine’s AUC following an i.v. injection of an equimolar cocaine dose. Sequestration of cocaine in plasma by h2E2, shown via reduction of cocaine’s Vdss, indicates potential clinical efficacy. Although the binding of cocaine to h2E2 in plasma should inhibit distribution and metabolism, the elimination of cocaine remained multicompartmental and was still rapidly eliminated from plasma despite the presence of h2E2. BE was the major cocaine metabolite, and brain BE concentrations were sixfold higher than in plasma, indicating that cocaine is normally metabolized in the brain. In the presence of h2E2, brain BE concentrations were decreased and plasma BE was increased, consistent with the observed h2E2-induced changes in cocaine disposition. The inhibition of cocaine distribution to the brain confirms the humanized mAb, h2E2, as a lead candidate for development as an immunotherapy for cocaine abuse. PMID:24733787

  1. c-Myc dependent expression of pro-apoptotic Bim renders HER2-overexpressing breast cancer cells dependent on anti-apoptotic Mcl-1.

    PubMed

    Campone, Mario; Noël, Bélinda; Couriaud, Cécile; Grau, Morgan; Guillemin, Yannis; Gautier, Fabien; Gouraud, Wilfried; Charbonnel, Catherine; Campion, Loïc; Jézéquel, Pascal; Braun, Frédérique; Barré, Benjamin; Coqueret, Olivier; Barillé-Nion, Sophie; Juin, Philippe

    2011-09-07

    Anti-apoptotic signals induced downstream of HER2 are known to contribute to the resistance to current treatments of breast cancer cells that overexpress this member of the EGFR family. Whether or not some of these signals are also involved in tumor maintenance by counteracting constitutive death signals is much less understood. To address this, we investigated what role anti- and pro-apoptotic Bcl-2 family members, key regulators of cancer cell survival, might play in the viability of HER2 overexpressing breast cancer cells. We used cell lines as an in vitro model of HER2-overexpressing cells in order to evaluate how anti-apoptotic Bcl-2, Bcl-xL and Mcl-1, and pro-apoptotic Puma and Bim impact on their survival, and to investigate how the constitutive expression of these proteins is regulated. Expression of the proteins of interest was confirmed using lysates from HER2-overexpressing tumors and through analysis of publicly available RNA expression data. We show that the depletion of Mcl-1 is sufficient to induce apoptosis in HER2-overexpressing breast cancer cells. This Mcl-1 dependence is due to Bim expression and it directly results from oncogenic signaling, as depletion of the oncoprotein c-Myc, which occupies regions of the Bim promoter as evaluated in ChIP assays, decreases Bim levels and mitigates Mcl-1 dependence. Consistently, a reduction of c-Myc expression by inhibition of mTORC1 activity abrogates occupancy of the Bim promoter by c-Myc, decreases Bim expression and promotes tolerance to Mcl-1 depletion. Western blot analysis confirms that naïve HER2-overexpressing tumors constitutively express detectable levels of Mcl-1 and Bim, while expression data hint on enrichment for Mcl-1 transcripts in these tumors. This work establishes that, in HER2-overexpressing tumors, it is necessary, and maybe sufficient, to therapeutically impact on the Mcl-1/Bim balance for efficient induction of cancer cell death.

  2. A mathematical model of a recombinant humanized anti-cocaine monoclonal antibody's effects on cocaine pharmacokinetics in mice.

    PubMed

    Wetzel, Hanna N; Zhang, Tongli; Norman, Andrew B

    2017-09-01

    A recombinant humanized anti-cocaine monoclonal antibody (mAb), h2E2, is at an advanced stage of pre-clinical development as an immunotherapy for cocaine abuse. It is hypothesized that h2E2 binds to and sequesters cocaine in the blood. A three-compartment model of the effects of h2E2 on cocaine's distribution was constructed. The model assumes that h2E2 binds to cocaine and that the h2E2-cocaine complex does not enter the brain but distributes between the central and peripheral compartments. Free cocaine is eliminated from both the central and peripheral compartments, and h2E2 and the h2E2-cocaine complex are eliminated from the central compartment only. This model was tested against a new dataset measuring cocaine concentrations in the brain and plasma over 1h in the presence and absence of h2E2. The mAb significantly increased plasma cocaine concentrations with a concomitant significant decrease in brain concentration. Plasma concentrations declined over the 1-hour sampling period in both groups. With a set of parameters within reasonable physiological ranges, the three-compartment model was able to qualitatively and quantitatively simulate the increased plasma concentration in the presence of the antibody and the decreased peak brain concentration in the presence of antibody. Importantly, the model explained the decline in plasma concentrations over time as distribution of the cocaine-h2E2 complex into a peripheral compartment. This model will facilitate the targeting of ideal mAb PK/PD properties thus accelerating the identification of lead candidate anti-drug mAbs. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. The Human Splice Variant Δ16HER2 Induces Rapid Tumor Onset in a Reporter Transgenic Mouse

    PubMed Central

    Iezzi, Manuela; Zenobi, Santa; Montani, Maura; Pietrella, Lucia; Kalogris, Cristina; Rossini, Anna; Ciravolo, Valentina; Castagnoli, Lorenzo; Tagliabue, Elda; Pupa, Serenella M.; Musiani, Piero; Monaci, Paolo; Menard, Sylvie; Amici, Augusto

    2011-01-01

    Several transgenic mice models solidly support the hypothesis that HER2 (ERBB2) overexpression or mutation promotes tumorigenesis. Recently, a HER2 splice variant lacking exon-16 (Δ16HER2) has been detected in human breast carcinomas. This alternative protein, a normal byproduct of HER2, has an increased transforming potency compared to wild-type (wt) HER2 receptors. To examine the ability of Δ16HER2 to transform mammary epithelium in vivo and to monitor Δ16HER2-driven tumorigenesis in live mice, we generated and characterized a mouse line that transgenically expresses both human Δ16HER2 and firefly luciferase under the transcriptional control of the MMTV promoter. All the transgenic females developed multifocal mammary tumors with a rapid onset and an average latency of 15.11 weeks. Immunohistochemical analysis revealed the concurrent expression of luciferase and the human Δ16HER2 oncogene only in the mammary gland and in strict correlation with tumor development. Transgenic Δ16HER2 expressed on the tumor cell plasma membrane from spontaneous mammary adenocarcinomas formed constitutively active homodimers able to activate the oncogenic signal transduction pathway mediated through Src kinase. These new transgenic animals demonstrate the ability of the human Δ16HER2 isoform to transform “per se” mammary epithelium in vivo. The high tumor incidence as well as the short latency strongly suggests that the Δ16HER2 splice variant represents the transforming form of the HER2 oncoprotein. PMID:21559085

  4. Microglial internalization and degradation of pathological tau is enhanced by an anti-tau monoclonal antibody

    PubMed Central

    Luo, Wenjie; Liu, Wencheng; Hu, Xiaoyan; Hanna, Mary; Caravaca, April; Paul, Steven M.

    2015-01-01

    Microglia have been shown to contribute to the clearance of brain amyloid β peptides (Aβ), the major component of amyloid plaques, in Alzheimer’s disease (AD). However, it is not known whether microglia play a similar role in the clearance of tau, the major component of neurofibrillary tangles (NFTs). We now report that murine microglia rapidly internalize and degrade hyperphosphorylated pathological tau isolated from AD brain tissue in a time-dependent manner in vitro. We further demonstrate that microglia readily degrade human tau species released from AD brain sections and eliminate NFTs from brain sections of P301S tauopathy mice. The anti-tau monoclonal antibody MC1 enhances microglia-mediated tau degradation in an Fc-dependent manner. Our data identify a potential role for microglia in the degradation and clearance of pathological tau species in brain and provide a mechanism explaining the potential therapeutic actions of passively administered anti-tau monoclonal antibodies. PMID:26057852

  5. Anti-Tumor Effects of Peptide Therapeutic and Peptide Vaccine Antibody Co-targeting HER-1 and HER-2 in Esophageal Cancer (EC) and HER-1 and IGF-1R in Triple-Negative Breast Cancer (TNBC).

    PubMed

    Overholser, Jay; Ambegaokar, Kristen Henkins; Eze, Siobhan M; Sanabria-Figueroa, Eduardo; Nahta, Rita; Bekaii-Saab, Tanios; Kaumaya, Pravin T P

    2015-07-06

    Despite the promise of targeted therapies, there remains an urgent need for effective treatment for esophageal cancer (EC) and triple-negative breast cancer (TNBC). Current FDA-approved drugs have significant problems of toxicity, safety, selectivity, efficacy and development of resistance. In this manuscript, we demonstrate that rationally designed peptide vaccines/mimics are a viable therapeutic strategy for blocking aberrant molecular signaling pathways with high affinity, specificity, potency and safety. Specifically, we postulate that novel combination treatments targeting members of the EGFR family and IGF-1R will yield significant anti-tumor effects in in vitro models of EC and TNBC possibly overcoming mechanisms of resistance. We show that the combination of HER-1 and HER-2 or HER-1 and IGF-1R peptide mimics/vaccine antibodies exhibited enhanced antitumor properties with significant inhibition of tumorigenesis in OE19 EC and MDA-MB-231 TNBC cell lines. Our work elucidates the mechanisms of HER-1/IGF-1R and HER-1/HER-2 signaling in these cancer cell lines, and the promising results support the rationale for dual targeting with HER-1 and HER-2 or IGF-1R as an improved treatment regimen for advanced therapy tailored to difference types of cancer.

  6. Altered antigenicity of human monoclonal antibodies derived from human-mouse heterohybridomas.

    PubMed

    Kan-Mitchell, J; Andrews, K L; Gallardo, D; Mitchell, M S

    1987-04-01

    We have generated milligram quantities of human monoclonal antibodies (Hu-MAbs) in the ascites of pristane-primed nude mice injected with human-mouse heterohybridomas. After contaminating mouse immunoglobulins were removed by affinity chromatography, an enzyme immunosorbent assay (EIA) was used to measure the concentrations of human immunoglobulins. Ten different partially purified preparations were tested. The titration curves with all 5 IgG Hu-MAbs were unusual, reaching a plateau at a very low apparent maximum concentration of antibody. In contrast, the EIA yielded more usual titration curves and thus apparently more reliable estimates of the concentrations of 4 IgM and 1 IgA monoclonal antibodies. An analogous EIA for the quantitation of mouse IgG monoclonal antibodies also gave accurate estimates. To understand the nature of the discrepancy with human IgG, 5 Hu-MAbs of the 3 classes (2 IgG, 2 pentameric IgM and 1 IgA) were purified to homogeneity for a more detailed analysis. The inability to quantitate the human IgG monoclonal antibodies by EIA was not due to defective molecules, as shown by SDS polyacrylamide gel electrophoresis. The human IgG monoclonal antibodies were found to consist of intact heavy and light chains, as were the IgM and IgA antibodies. The possibility that the human IgG monoclonal antibodies differed antigenically from polyclonal IgG was explored by comparing the concentrations by EIA with the protein concentrations determined by absorbance at 280 nm. This analysis permitted a comparison of the detectability of antigenic determinants on Hu-MAbs with those on polyclonal Ig with goat antibodies to Ig or Ig subclass. The IgG monoclonal antibodies differed from polyclonal IgG in both their heavy and light chains. Goat antiserum monospecific for the gamma chain in fact underestimated the concentration by as much as one hundred-fold. IgM and IgA monoclonal antibodies were less antigenically distinct from their polyclonal counterparts even

  7. Blockade of a key region in the extracellular domain inhibits HER2 dimerization and signaling.

    PubMed

    Menendez, Javier A; Schroeder, Barbara; Peirce, Susan K; Vellon, Luciano; Papadimitropoulou, Adriana; Espinoza, Ingrid; Lupu, Ruth

    2015-06-01

    Several treatment strategies target the human epidermal growth factor receptor 2 (HER2) in breast carcinomas, including monoclonal antibodies directed against HER2's extracellular domain (ECD) and small molecule inhibitors of its tyrosine kinase activity. Yet, novel therapies are needed that prevent HER2 dimerization with other HER family members, because current treatments are only partially effective. To test the hypothesis that HER2 activation requires a protein sequence in the HER2-ECD that mediates HER2 homo- and heterodimerization, we introduced a series of deletion mutations in the third subdomain of HER2-ECD. These deletion mutants were retrovirally expressed in breast cancer (BC) cells that naturally overexpress HER2 and in noncancerous, HER2-negative breast epithelial cells. One-factor analysis of variance or Student's t test were used to analyze differences. All statistical tests were two-sided. The smallest deletion in the ECD domain of HER2, which removed only 16 amino acids (HER2-ECDΔ451-466), completely disrupted the oncogenic potential of HER2. In contrast to wild-type HER2, the mutant-inhibited anchorage-independent growth (mean number of colonies: mutant, 70, 95% confidence interval [CI] = 55 to 85; wild-type, 400, 95% CI = 320 to 480, P < .001) increased sensitivity to paclitaxel treatment in both transformed and nontransformed cells. Overexpression of HER2Δ451-466 efficiently inhibited activation of HER1, HER2, and HER3 in all cell lines tested. These findings reveal that an essential "activating" sequence exists in the extracellular domain of HER2. Disruption of this sequence disables the HER2 dimerization loop, blocks subsequent activation of HER2-driven oncogenic signaling, and generates a dominant-negative form of HER2. Reagents specifically against this molecular activation switch may represent a novel targeted approach for the management of HER2-overexpressing carcinomas. © The Author 2015. Published by Oxford University Press. All

  8. Variables influencing anti-human immunodeficiency virus type 1 neutralizing human monoclonal antibody (NhMAb) production among infected Thais.

    PubMed

    Akapirat, Siriwat; Avihingsanon, Anchalee; Ananworanich, Jintanat; Schuetz, Alexandra; Ramasoota, Pongrama; Luplertlop, Natthanej; Ono, Ken-Ichiro; Ikuta, Kazuyoshi; Utachee, Piraporn; Kameoka, Masanori; Leaungwutiwong, Pornsawan

    2013-09-01

    We conducted this study to determine the clinical variables associated with the production of human immunodeficiency virus type 1 (HIV-1) circulating recombinant form (CRF) 01_AE neutralizing human monoclonal antibodies (NhMAbs) using a hybridoma technique. This cross sectional study was performed in 20 asymptomatic HIV-1-infected Thais. Peripheral blood mononuclear cells (PBMCs) were obtained from each study participant and fused with SPYMEG cells. Culture supernatant collected from growing hybridomas was tested for neutralizing activity against HIV-1 CRF01_AE Env-recombinant viruses. Fifty hybridomas expressing anti-HIV-1 NhMAbs with strong neutralizing activity against at least 1 CRF01_AE Env-recombinant virus were found. A positive association between the numbers of hybridomas produced and the CD4 counts of study participants (p = 0.019) was observed. NhMAb-producing hybridomas with strong neutralizing activity were mostly found in participans diagnosed with HIV-1 infection within the previous 1 year. The HIV-1 viral load was not significantly correlated with the numbers of either established hybridomas or clones expressing anti-HIV-1 NhMAbs with strong neutralizing activity. To our knowledge, this is the first study of NhMAb-producing hybridomas obtained from HIV-1 CRF01_AE-infected populations identified by antibody binding to HIV-1 V3 loop peptide enzyme-linked immunosorbent assay (ELISA) or TRUGENE HIV-1 Genotyping Assay (HIV-1 pol sequence). It provides important criterion to slect study participants with high CD4 counts who produce large numbers of hybridoma clones. The results are valuable for further studies related to nurtalizing antibodies production and HIV-1 vaccine development.

  9. HER2 over-expressing high grade endometrial cancer expresses high levels of p95HER2 variant.

    PubMed

    Growdon, Whitfield B; Groeneweg, Jolijn; Byron, Virginia; DiGloria, Celeste; Borger, Darrell R; Tambouret, Rosemary; Foster, Rosemary; Chenna, Ahmed; Sperinde, Jeff; Winslow, John; Rueda, Bo R

    2015-04-01

    Subsets of high grade endometrial cancer (EnCa) over-express HER2 (ERBB2), yet clinical trials have failed to demonstrate any anti-tumor activity utilizing trastuzumab, an approved platform for HER2 positive breast cancer (BrCa). A truncated p95HER2 variant lacking the trastuzumab binding site may confer resistance. The objective of this investigation was to characterize the expression of the p95HER2 truncated variant in EnCa. With institutional approval, 86 high grade EnCa tumors were identified with tumor specimens from surgeries performed between 2000 and 2011. Clinical data were collected and all specimens underwent tumor genotyping, HER2 immunohistochemistry (IHC, HercepTest®), HER2 fluorescent in situ hybridization (FISH), along with total HER2 (H2T) and p95HER2 assessment with VeraTag® testing. Regression models were used to compare a cohort of 86 breast tumors selected for equivalent HER2 protein expression. We identified 44 high grade endometrioid and 42 uterine serous carcinomas (USC). IHC identified high HER2 expression (2+ or 3+) in 59% of the tumors. HER2 gene amplification was observed in 16 tumors (12 USC, 4 endometrioid). Both HER2 gene amplification and protein expression correlated with H2T values. High p95HER2 expression above 2.8RF/mm2 was observed in 53% (n=54) with significant correlation with H2T levels. When matched to a cohort of 107 breast tumors based on HercepTest HER2 expression, high grade EnCa presented with higher p95 levels (p<0.001). These data demonstrate that compared to BrCa, high grade EnCa expresses higher levels of p95HER2 possibly providing rationale for the trastuzumab resistance observed in EnCa. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Docetaxel immunonanocarriers as targeted delivery systems for HER 2-positive tumor cells: preparation, characterization, and cytotoxicity studies.

    PubMed

    Koopaei, Mona Noori; Dinarvand, Rassoul; Amini, Mohsen; Rabbani, Hojatollah; Emami, Shaghayegh; Ostad, Seyed Nasser; Atyabi, Fatemeh

    2011-01-01

    The objective of this study was to develop pegylated poly lactide-co-glycolide acid (PLGA) immunonanocarriers for targeting delivery of docetaxel to human breast cancer cells. The polyethylene glycol (PEG) groups on the surface of the PLGA nanoparticles were functionalized using maleimide groups. Trastuzumab, a monoclonal antibody against human epidermal growth factor receptor 2 (HER2) antigens of cancer cells, used as the targeting moiety, was attached to the maleimide groups on the surface of pegylated PLGA nanoparticles. Nanoparticles prepared by a nanoprecipitation method were characterized for their size, size distribution, surface charge, surface morphology, drug-loading, and in vitro drug release profile. The average size of the trastuzumab-decorated nanoparticles was 254 ± 16.4 nm and their zeta potential was -11.5 ± 1.4 mV. The average size of the nontargeted PLGA nanoparticles was 183 ± 22 nm and their zeta potential was -2.6 ± 0.34 mV. The cellular uptake of nanoparticles was studied using both HER2-positive (SKBR3 and BT-474) and HER2-negative (Calu-6) cell lines. The cytotoxicity of the immunonanocarriers against HER2-positive cell lines was significantly higher than that of nontargeted PLGA nanoparticles and free docetaxel.

  11. Recent advances in systemic therapy: Advances in systemic therapy for HER2-positive metastatic breast cancer.

    PubMed

    Morrow, Phuong Khanh H; Zambrana, Francisco; Esteva, Francisco J

    2009-01-01

    Human epidermal growth factor receptor (HER)2 over-expression is associated with a shortened disease-free interval and poor survival. Although the addition of trastuzumab to chemotherapy in the first-line setting has improved response rates, progression-free survival, and overall survival, response rates declined when trastuzumab was used beyond the first-line setting because of multiple mechanisms of resistance. Studies have demonstrated the clinical utility of continuing trastuzumab beyond progression, and further trials to explore this concept are ongoing. New tyrosine kinase inhibitors, monoclonal antibodies, PTEN (phosphatase and tensin homolog) pathway regulators, HER2 antibody-drug conjugates, and inhibitors of heat shock protein-90 are being evaluated to determine whether they may have a role to play in treating trastuzumab-resistant metastatic breast cancer.

  12. HER2 induced EMT and tumorigenicity in breast epithelial progenitor cells is inhibited by coexpression of EGFR.

    PubMed

    Ingthorsson, S; Andersen, K; Hilmarsdottir, B; Maelandsmo, G M; Magnusson, M K; Gudjonsson, T

    2016-08-11

    The members of the epidermal growth factor receptor (EGFR) kinase family are important players in breast morphogenesis and cancer. EGFR2/HER2 and EGFR expression have a prognostic value in certain subtypes of breast cancer such as HER2-amplified, basal-like and luminal type B. Many clinically approved small molecular inhibitors and monoclonal antibodies have been designed to target HER2, EGFR or both. There is, however, still limited knowledge on how the two receptors are expressed in normal breast epithelium, what effects they have on cellular differentiation and how they participate in neoplastic transformation. D492 is a breast epithelial cell line with stem cell properties that can undergo epithelial to mesenchyme transition (EMT), generate luminal- and myoepithelial cells and form complex branching structures in three-dimensional (3D) culture. Here, we show that overexpression of HER2 in D492 (D492(HER2)) resulted in EMT, loss of contact growth inhibition and increased oncogenic potential in vivo. HER2 overexpression, furthermore, inhibited endogenous EGFR expression. Re-introducing EGFR in D492(HER2) (D492(HER2/EGFR)) partially reversed the mesenchymal state of the cells, as an epithelial phenotype reappeared both in 3D cultures and in vivo. The D492(HER2/EGFR) xenografts grow slower than the D492(HER2) tumors, while overexpression of EGFR alone (D492(EGFR)) was not oncogenic in vivo. Consistent with the EGFR-mediated epithelial phenotype, overexpression of EGFR drove the cells toward a myoepithelial phenotype in 3D culture. The effect of two clinically approved anti-HER2 and EGFR therapies, trastuzumab and cetuximab, was tested alone and in combination on D492(HER2) xenografts. While trastuzumab had a growth inhibitory effect compared with untreated control, the effect of cetuximab was limited. When administered in combination, the growth inhibitory effect of trastuzumab was less pronounced. Collectively, our data indicate that in HER2-overexpressing D492

  13. HER2 induced EMT and tumorigenicity in breast epithelial progenitor cells is inhibited by coexpression of EGFR

    PubMed Central

    Ingthorsson, S; Andersen, K; Hilmarsdottir, B; Maelandsmo, G M; Magnusson, M K; Gudjonsson, T

    2016-01-01

    The members of the epidermal growth factor receptor (EGFR) kinase family are important players in breast morphogenesis and cancer. EGFR2/HER2 and EGFR expression have a prognostic value in certain subtypes of breast cancer such as HER2-amplified, basal-like and luminal type B. Many clinically approved small molecular inhibitors and monoclonal antibodies have been designed to target HER2, EGFR or both. There is, however, still limited knowledge on how the two receptors are expressed in normal breast epithelium, what effects they have on cellular differentiation and how they participate in neoplastic transformation. D492 is a breast epithelial cell line with stem cell properties that can undergo epithelial to mesenchyme transition (EMT), generate luminal- and myoepithelial cells and form complex branching structures in three-dimensional (3D) culture. Here, we show that overexpression of HER2 in D492 (D492HER2) resulted in EMT, loss of contact growth inhibition and increased oncogenic potential in vivo. HER2 overexpression, furthermore, inhibited endogenous EGFR expression. Re-introducing EGFR in D492HER2 (D492HER2/EGFR) partially reversed the mesenchymal state of the cells, as an epithelial phenotype reappeared both in 3D cultures and in vivo. The D492HER2/EGFR xenografts grow slower than the D492HER2 tumors, while overexpression of EGFR alone (D492EGFR) was not oncogenic in vivo. Consistent with the EGFR-mediated epithelial phenotype, overexpression of EGFR drove the cells toward a myoepithelial phenotype in 3D culture. The effect of two clinically approved anti-HER2 and EGFR therapies, trastuzumab and cetuximab, was tested alone and in combination on D492HER2 xenografts. While trastuzumab had a growth inhibitory effect compared with untreated control, the effect of cetuximab was limited. When administered in combination, the growth inhibitory effect of trastuzumab was less pronounced. Collectively, our data indicate that in HER2-overexpressing D492 cells, EGFR can

  14. Assessment of ability of murine and human anti-lipid A monoclonal antibodies to bind and neutralize lipopolysaccharide

    PubMed Central

    1993-01-01

    The use of monoclonal antibodies (mAbs) directed to lipid A for the therapy of gram-negative sepsis is controversial. In an attempt to understand their biologic basis of action, we used a fluid-phase radioimmunoassay to measure binding between bacterial lipopolysaccharide (LPS) and two IgM mAbs directed to lipid A that are being evaluated for the treatment of gram-negative bacterial sepsis. Both antibodies bound 3H-LPS prepared from multiple strains of gram- negative bacteria when large excesses of antibody were used, although binding was modest and only slightly greater than control preparations. We also studied the ability of each anti-lipid A antibody to neutralize some of the biological effects of LPS in vitro. Despite large molar excesses, neither antibody neutralized LPS as assessed by the limulus lysate test, by a mitogenic assay for murine splenocytes, or by the production of cytokines interleukin (IL)-1, IL-6, or tumor necrosis factor from human monocytes in culture medium or in whole blood. Our experiments do not support the hypothesis that either of these anti- lipid A mAbs function by neutralizing the toxic effects of LPS. PMID:8418211

  15. HER2-family signalling mechanisms, clinical implications and targeting in breast cancer.

    PubMed

    Elster, N; Collins, D M; Toomey, S; Crown, J; Eustace, A J; Hennessy, B T

    2015-01-01

    Approximately 20 % of human breast cancers (BC) overexpress HER2 protein, and HER2-positivity is associated with a worse prognosis. Although HER2-targeted therapies have significantly improved outcomes for HER2-positive BC patients, resistance to trastuzumab-based therapy remains a clinical problem. In order to better understand resistance to HER2-targeted therapies in HER2-positive BC, it is necessary to examine HER family signalling as a whole. An extensive literature search was carried out to critically assess the current knowledge of HER family signalling in HER2-positive BC and response to HER2-targeted therapy. Known mechanisms of trastuzumab resistance include reduced receptor-antibody binding (MUC4, p95HER2), increased signalling through alternative HER family receptor tyrosine kinases (RTK), altered intracellular signalling involving loss of PTEN, reduced p27kip1, or increased PI3K/AKT activity and altered signalling via non-HER family RTKs such as IGF1R. Emerging strategies to circumvent resistance to HER2-targeted therapies in HER2-positive BC include co-targeting HER2/PI3K, pan-HER family inhibition, and novel therapies such as T-DM1. There is evidence that immunity plays a key role in the efficacy of HER-targeted therapy, and efforts are being made to exploit the immune system in order to improve the efficacy of current anti-HER therapies. With our rapidly expanding understanding of HER2 signalling mechanisms along with the repertoire of HER family and other targeted therapies, it is likely that the near future holds further dramatic improvements to the prognosis of women with HER2-positive BC.

  16. [Construction of human phage antibody library and screening for human monoclonal antibodies of amylin].

    PubMed

    Gong, Qian; Li, Chang-ying; Chang, Ji-wu; Zhu, Tie-hong

    2012-06-01

    To screen monoclonal antibodies to amylin from a constructed human phage antibody library and identify their antigenic specificity and combining activities. The heavy chain Fd fragment and light chain of human immunoglobulin genes were amplified from peripheral blood lymphocytes of healthy donors using RT-PCR, and then inserted into phagemid pComb3XSS to generate a human phage antibody library. The insertion of light chain or heavy chain Fd genes were identified by PCR after the digestion of Sac I, Xba I, Xho Iand Spe I. One of positive clones was analyzed by DNA sequencing. The specific anti-amylin clones were screened from antibody library against human amylin antigens and then the positive clones were determined by Phage-ELISA analysis. A Fab phage antibody library with 0.8×10(8); members was constructed with the efficacy of about 70%. DNA sequence analysis indicated V(H); gene belonged to V(H);3 gene family and V(λ); gene belonged to the V(λ); gene family. Using human amylin as panning antigen, specific anti-amylin Fab antibodies were enriched by screening the library for three times. Phage-ELISA assay showed the positive clones had very good specificity to amylin antigen. The successful construction of a phage antibody library and the identification of anti-amylin Fab antibodies provide a basis for further study and preparation of human anti-amylin antibodies.

  17. Antibody targeting of HER2/HER3 signaling overcomes heregulin-induced resistance to PI3K inhibition in prostate cancer.

    PubMed

    Poovassery, Jayakumar S; Kang, Jeffrey C; Kim, Dongyoung; Ober, Raimund J; Ward, E Sally

    2015-07-15

    Dysregulated expression and/or mutations of the various components of the phosphoinositide 3-kinase (PI3K)/Akt pathway occur with high frequency in prostate cancer and are associated with the development and progression of castration resistant tumors. However, small molecule kinase inhibitors that target this signaling pathway have limited efficacy in inhibiting tumor growth, primarily due to compensatory survival signals through receptor tyrosine kinases (RTKs). Although members of the epidermal growth factor receptor (EGFR), or HER, family of RTKs are strongly implicated in the development and progression of prostate cancer, targeting individual members of this family such as EGFR or HER2 has resulted in limited success in clinical trials. Multiple studies indicate a critical role for HER3 in the development of resistance against both HER-targeted therapies and PI3K/Akt pathway inhibitors. In this study, we found that the growth inhibitory effect of GDC-0941, a class I PI3K inhibitor, is markedly reduced in the presence of heregulin. Interestingly, this effect is more pronounced in cells lacking phosphatase and tensin homolog function. Heregulin-mediated resistance to GDC-0941 is associated with reactivation of Akt downstream of HER3 phosphorylation. Importantly, combined blockade of HER2 and HER3 signaling by an anti-HER2/HER3 bispecific antibody or a mixture of anti-HER2 and anti-HER3 antibodies restores sensitivity to GDC-0941 in heregulin-treated androgen-dependent and -independent prostate cancer cells. These studies indicate that the combination of PI3K inhibitors with HER2/HER3 targeting antibodies may constitute a promising therapeutic strategy for prostate cancer. © 2014 UICC.

  18. The dynamics of HER2 status in esophageal adenocarcinoma

    PubMed Central

    Creemers, Aafke; Ebbing, Eva A.; Hooijer, Gerrit K.J.; Stap, Lisanne; Jibodh-Mulder, Rajni A.; Gisbertz, Susanne S.; van Berge Henegouwen, Mark I.; van Montfoort, Maurits L.; Hulshof, Maarten C.C.M.; Krishnadath, Kausilia K.; van Oijen, Martijn G.H.; Bijlsma, Maarten F.; Meijer, Sybren L.; van Laarhoven, Hanneke W.M.

    2018-01-01

    Trastuzumab, a monoclonal antibody against HER2, has become standard of care for metastatic HER2-overexpressing esophagogastric adenocarcinoma and is currently investigated as (neo)adjuvant treatment option in HER2-positive esophagogastric adenocarcinoma. The HER2 status is commonly determined on archived material of the primary tumor. However, this status may change over the course of treatment or disease progression. The aim of this study was to assess the dynamics of HER2 status in esophageal adenocarcinoma (EAC) in patients with resectable and recurrent disease, and to determine the associations of these changes with clinical outcome. Discordance, defined as any change in HER2 status between matched biopsy and post-neoadjuvant chemoradiation therapy resection specimen (N = 170), or between matched resection specimen and recurrence of patients not eligible for curative treatment (N = 61), was determined using the standardized HER2 status scoring system. Clinically relevant positive discordance was defined as a change to HER2 positive status, as this would imply eligibility for HER2-targeted therapy. A difference in HER2 status between biopsy and resection specimen and resection specimen and metachronous recurrence was observed in 2.1% (n = 3) and 3.3% (n = 2) of the paired cases, respectively. Clinically relevant discordance was detected in 1.4% (n = 2) of the resectable patients and 1.6% (n = 1) of the patients with recurrent disease. Patients with HER2-positive status tumors before start of neoadjuvant treatment showed better overall survival, but not statistically significant. No association between HER2 status discordance and survival was found. Clinically relevant HER2 status discordance was observed and in order to prevent under-treatment of patients, the assessment of HER2 status in the metastatic setting should preferably be performed on the most recently developed lesions if the previous HER2 assessment on archival material of the primary tumor was

  19. Production of human monoclonal IgG antibodies against Rhesus (D) antigen.

    PubMed Central

    Bron, D; Feinberg, M B; Teng, N N; Kaplan, H S

    1984-01-01

    An Epstein-Barr virus (EBV)-transformed human B-cell line ( LB4r ) producing anti-Rhesus [Rho(D) antigen] antibody was fused with a non-immunoglobulin-producing mouse-human heteromyeloma ( SHM - D33 ) and selected in hypoxanthine/aminopterin/thymidine medium containing 0.5 microM ouabain. Surviving hybrids found to secrete specific anti-Rho(D) antibody were cloned by limiting dilution. Two clones (D4-B2 and E10-C1) producing high levels (12 and 20 micrograms/ml per 10(6) cells per 24 hr, respectively) of monospecific antibody (IgG3, lambda chain) were selected for expansion and further characterization. Compared to the parental cell line ( LB4r ), these hybridoma cell lines presented several advantages: antibody production was increased 10-fold, cloning efficiency was improved, and the EBV genome was not retained. Antibody production has been stable for greater than 8 months. These human monoclonal anti-Rho(D) antibodies have demonstrated utility in routine blood-group typing. They may also prove useful in the biochemical and genetic characterization of the Rh antigen system. Most important, they offer a source of Rh-immune globulin for the prevention of Rh immunization and alloimmune hemolytic disease of the newborn. Images PMID:6427767

  20. Reactivity of human monoclonal IgM with nerve glycosphingolipids.

    PubMed Central

    Hauttecoeur, B; Schmitt, C; Dubois, C; Danon, F; Brouet, J C

    1990-01-01

    We examined the reactivity of monoclonal IgM of sera from patients with neuropathy and monoclonal IgM, with or without antibody activity to myelin-associated glycoprotein (MAG), as well as sera from non-neurologic patients with Waldenström's macroglobulinaemia, with various nerve glycolipids extracts or with purified gangliosides. As expected from previous studies, all (five cases) anti-MAG IgM stained two glycolipids, the chemical characteristics of which corresponded to sulphated glucuronyl-paragloboside (SGPG) and sulphated glucuronyl-lactosaminyl-paragloboside (SGLPG). Five of 12 sera from patients with neuropathy whose IgM was devoid of anti-MAG reactivity stained nerve extracts greatly enriched (98%) with SGPG and SGLPG. Three of these five sera reacted with additional glycolipids and/or gangliosides. Two of 16 sera from patients with macroglobulinaemia without neuropathy reacted strongly with both SGPG and SGLPG. The latter finding as well as the detection of low titre of anti-sphingolipid antibodies in normal sera may cast a doubt on the pathogenetic significance of this antibody activity. Images Fig. 1 Fig. 2 Fig. 3 PMID:1694117

  1. A virosomal formulated Her-2/neu multi-peptide vaccine induces Her-2/neu-specific immune responses in patients with metastatic breast cancer: a phase I study.

    PubMed

    Wiedermann, Ursula; Wiltschke, C; Jasinska, J; Kundi, M; Zurbriggen, R; Garner-Spitzer, E; Bartsch, R; Steger, G; Pehamberger, H; Scheiner, O; Zielinski, C C

    2010-02-01

    We have previously shown in mice that vaccination with three Her-2-peptides representing B-cell epitopes of the extracellular domain of Her-2/neu induces Her-2/neu-specific IgG antibodies with strong anti-tumor activity in vitro and in vivo. We have now finalized a phase I clinical trial with an anti-Her-2/neu vaccine-construct of immunopotentiating reconstituted influenza virosomes with the three peptides in patients with metastatic breast cancer (MBC). Ten MBC patients with low protein overexpression of Her-2/neu of MBC (+ or ++ upon immunohistochemistry, FISH negative) and positive hormone receptor status were enrolled in a single center phase I study. The virosomal formulated vaccine, consisting of 10 microg/peptide, was intramuscularly applied three times on days 1, 28, and 56. The primary endpoint of the study, which lasted 12 weeks, was safety, the secondary endpoint immunogenicity. Local erythema at the injection site was the only vaccine-related side effect occurring in four patients. In 8 of 10 patients an increase in peptide-specific antibody titer measured by ELISA was found. Importantly, the induced antibodies were also directed against the native Her-2/neu protein. Cellular immune responses, as measured by in vitro production of IL-2, IFN-c, and TNF-a of PBMCs showed a marked increase after vaccination in the majority of vaccinees. Notably, the number of CD4+CD25+Foxp3+T regulatory cells, which were significantly increased compared to healthy controls prior to vaccination, was markedly reduced following vaccination. In all, the immunological responses after vaccination indicated that the patients in stage IV of disease were immunocompetent and susceptible to vaccination. The Her-2/neu multipeptide vaccine was safe, well tolerated and effective in overcoming immunological tolerance to Her-2/neu. The induction of anti-Her-2-specific antibodies could result in clinical benefit comparable to passive anti-Her-2 antibody therapy.

  2. Molecular analysis of HER2 signaling in human breast cancer by functional protein pathway activation mapping

    PubMed Central

    Wulfkuhle, Julia D.; Berg, Daniela; Wolff, Claudia; Langer, Rupert; Tran, Kai; Illi, Julie; Espina, Virginia; Pierobon, Mariaelena; Deng, Jianghong; DeMichele, Angela; Walch, Axel; Bronger, Holger; Becker, Ingrid; Waldhör, Christine; Höfler, Heinz; Esserman, Laura; Liotta, Lance A.; Becker, Karl-Friedrich; Petricoin, Emanuel F.

    2017-01-01

    Purpose Targeting of the HER2 protein in human breast cancer represents a major advance in oncology, but relies on measurements of total HER2 protein and not HER2 signaling network activation. We utilized reverse phase protein microarrays (RPMAs) to measure total and phosphorylated HER2 in the context of HER family signaling to understand correlations between phosphorylated and total levels of HER2 and downstream signaling activity. Experimental Design Three independent study sets, comprising a total of 415 individual patient samples from flash frozen core biopsy samples and FFPE surgical and core samples, were analyzed via RPMA. The phosphorylation and total levels of the HER receptor family proteins and downstream signaling molecules were measured in laser capture microdissected (LCM) enriched tumor epithelium from 127 frozen pre-treatment core biopsy samples and whole tissue lysates from 288 FFPE samples and these results were compared to FISH and IHC. Results RPMA measurements of total HER2 were highly concordant (> 90% all sets) with FISH and/or IHC data, as was phosphorylation of HER2 in the FISH/IHC+ population. Phosphorylation analysis of HER family signaling identified HER2 activation in some FISH/IHC- tumors and, identical to that seen with FISH/IHC+ tumors, the HER2 activation was concordant with EGFR and HER3 phosphorylation and downstream signaling endpoint activation. Conclusions Molecular profiling of HER2 signaling of a large cohort of human breast cancer specimens using a quantitative and sensitive functional pathway activation mapping technique reveals IHC-/FISH-/pHER2+ tumors with HER2 pathway activation independent of total HER2 levels and functional signaling through HER3 and EGFR. PMID:23045247

  3. Upregulation of mucin4 in ER-positive/HER2-overexpressing breast cancer xenografts with acquired resistance to endocrine and HER2-targeted therapies.

    PubMed

    Chen, Albert C; Migliaccio, Ilenia; Rimawi, Mothaffar; Lopez-Tarruella, Sara; Creighton, Chad J; Massarweh, Suleiman; Huang, Catherine; Wang, Yen-Chao; Batra, Surinder K; Gutierrez, M Carolina; Osborne, C Kent; Schiff, Rachel

    2012-07-01

    We studied resistance to endocrine and HER2-targeted therapies using a xenograft model of estrogen receptor positive (ER)/HER2-overexpressing breast cancer. Here, we report a novel phenotype of drug resistance in this model. MCF7/HER2-18 xenografts were treated with endocrine therapy alone or in combination with lapatinib and trastuzumab (LT) to inhibit HER2. Archival tumor tissues were stained with hematoxylin and eosin and with mucicarmine. RNA extracted from tumors at early time points and late after acquired resistance were analyzed for mucin4 (MUC4) expression by microarray and quantitative reverse transcriptase-PCR. Protein expression of the MUC4, ER, and HER2 signaling pathways was measured by immunohistochemistry and western blotting. The combination of the potent anti-HER2 regimen LT with either tamoxifen (Tam + LT) or estrogen deprivation (ED + LT) can cause complete eradication of ER-positive/HER2-overexpressing tumors in mice. Tumors developing resistance to this combination, as well as those acquiring resistance to endocrine therapy alone, exhibited a distinct histological and molecular phenotype-a striking increase in mucin-filled vacuoles and upregulation of several mucins including MUC4. At the onset of resistance, MUC4 mRNA and protein were increased. These tumors also showed upregulation and reactivation of HER2 signaling, while losing ER protein and the estrogen-regulated gene progesterone receptor. Mucins are upregulated in a preclinical model of ER-positive/HER2-overexpressing breast cancer as resistance develops to the combination of endocrine and anti-HER2 therapy. These mucin-rich tumors reactivate the HER2 pathway and shift their molecular phenotype to become more ER-negative/HER2-positive.

  4. Upregulation of Mucin4 in ER-positive/HER2-Overexpressing Breast Cancer Xenografts with Acquired Resistance to Endocrine and HER2-Targeted Therapies

    PubMed Central

    Chen, Albert C.; Migliaccio, Ilenia; Rimawi, Mothaffar; Lopez-Tarruella, Sara; Creighton, Chad J.; Massarweh, Suleiman; Huang, Catherine; Wang, Yen-Chao; Batra, Surinder K.; Gutierrez, M. Carolina; Osborne, C. Kent; Schiff, Rachel

    2012-01-01

    Background We studied resistance to endocrine and HER2-targeted therapies using a xenograft model of estrogen receptor positive (ER)/HER2-overexpressing breast cancer. Here, we report a novel phenotype of drug resistance in this model. Methods MCF7/HER2-18 xenografts were treated with endocrine therapy alone or in combination with lapatinib and trastuzumab (LT) to inhibit HER2. Archival tumor tissues were stained with hematoxylin & eosin and mucicarmine. RNA extracted from tumors at early time points and late after acquired resistance were analyzed for mucin4 (MUC4) expression by microarray and quantitative reverse transcriptase-PCR. Protein expression of the MUC4, ER and HER2 signaling pathways was measured by immunohistochemistry and Western blotting. Results The combination of the potent anti-HER2 regimen LT with either tamoxifen (Tam+LT) or estrogen deprivation (ED+LT) can cause complete eradication of ER-positive/HER2-overexpressing tumors in mice. Tumors developing resistance to this combination, as well as those acquiring resistance to endocrine therapy alone, exhibited a distinct histological and molecular phenotype—a striking increase in mucin-filled vacuoles and upregulation of several mucins including MUC4. At the onset of resistance, MUC4 mRNA and protein were increased. These tumors also showed upregulation and reactivation of HER2 signaling, while losing ER protein and the estrogen-regulated gene, progesterone receptor. Conclusions Mucins are upregulated in a preclinical model of ER-positive/HER2-overexpressing breast cancer as resistance develops to the combination of endocrine and anti-HER2 therapy. These mucin-rich tumors reactivate the HER2 pathway and shift their molecular phenotype to become more ER-negative/HER2-positive. PMID:22644656

  5. Virus-resembling nano-structures for near infrared fluorescence imaging of ovarian cancer HER2 receptors

    NASA Astrophysics Data System (ADS)

    Guerrero, Yadir A.; Bahmani, Baharak; Singh, Sheela P.; Vullev, Valentine I.; Kundra, Vikas; Anvari, Bahman

    2015-10-01

    Ovarian cancer remains the dominant cause of death due to malignancies of the female reproductive system. The capability to identify and remove all tumors during intraoperative procedures may ultimately reduce cancer recurrence, and lead to increased patient survival. The objective of this study is to investigate the effectiveness of an optical nano-structured system for targeted near infrared (NIR) imaging of ovarian cancer cells that over-express the human epidermal growth factor receptor 2 (HER2), an important biomarker associated with ovarian cancer. The nano-structured system is comprised of genome-depleted plant-infecting brome mosaic virus doped with NIR chromophore, indocyanine green, and functionalized at the surface by covalent attachment of monoclonal antibodies against the HER2 receptor. We use absorption and fluorescence spectroscopy, and dynamic light scattering to characterize the physical properties of the constructs. Using fluorescence imaging and flow cytometry, we demonstrate the effectiveness of these nano-structures for targeted NIR imaging of HER2 receptors in vitro. These functionalized nano-materials may provide a platform for NIR imaging of ovarian cancer.

  6. Combination therapies for the treatment of HER2-positive breast cancer: current and future prospects.

    PubMed

    Brandão, Mariana; Pondé, Noam F; Poggio, Francesca; Kotecki, Nuria; Salis, Mauren; Lambertini, Matteo; de Azambuja, Evandro

    2018-05-24

    HER2-positive disease is an aggressive subtype of breast cancer that has been revolutionized by anti-HER2 directed therapies. Multiple drugs have been developed and are currently in clinical use, including trastuzumab, lapatinib, pertuzumab, T-DM1, and neratinib, alone or combined in 'dual HER2-blockade' regimens. Areas covered: A comprehensive literature review was performed regarding the current state and the future of combination regimens containing anti-HER2 agents, focusing on their efficacy, toxicity, and cost-effectiveness. Expert commentary: The combination of trastuzumab/pertuzumab is approved in all disease settings, while trastuzumab/neratinib is approved in the adjuvant setting and trastuzumab/lapatinib in metastatic disease. Meanwhile, as breast cancer biology and resistance mechanisms become clearer, combinations with drugs like PI3K/Akt/mTOR inhibitors, CDK4/6 inhibitors, anti-PD(L)1 antibodies, endocrine therapy, and new anti-HER2 agents (panHER and HER2 tyrosine kinase inhibitors, bispecific antibodies, anti-HER3 antibodies, and antibody-drug conjugates) are being extensively tested in clinical trials. More specific strategies for the 'triple-positive' (estrogen receptor-positive/HER2-positive) disease are also being explored. However, there is an urgent need for the development of predictive biomarkers for a better tailoring of anti-HER2 directed therapy. This is the only way to further improve clinical outcomes and quality of life and to decrease costs and toxicities of unnecessary treatments.

  7. NSCLC and HER2: between lights and shadows.

    PubMed

    Ricciardi, Giuseppina Rosaria Rita; Russo, Alessandro; Franchina, Tindara; Ferraro, Giuseppa; Zanghì, Mariangela; Picone, Antonio; Scimone, Antonino; Adamo, Vincenzo

    2014-12-01

    The therapeutic landscape of non-small-cell lung cancer (NSCLC) has dramatically changed in the last few years with the introduction of molecularly targeted agents, leading to unprecedented results in lung tumors with a paradigmatic shift from a "one size fits all" approach to an histologic and molecular-based approach. The discovery of epidermal growth factor receptor (EGFR) mutations in NSCLC in 2004 and the marked response to the EGFR tyrosine kinase inhibitor gefitinib, in a small subset of patients harboring these genetic abnormalities, stimulated the study of other kinase mutants involvement in NSCLC. The incredible story of ALK rearranged tumors, with the rapid Food and Drug Administration approval of Crizotinib after only 4 years from the discovery of EML4-ALK translocation in NSCLC, has profoundly influenced the concept of drug development in NSCLC, paving the way to a novel series of molecularly selected studies with specific inhibitors. The identification of these oncogenic drivers has dramatically changed the genetic landscape of NSCLC moving away from the old concept of a large indistinct histological entity to a combination of rare clinically relevant molecular subsets. Recently, a renewed interest has been emerging on the human epidermal growth factor-2 (HER2) pathway. Genetic aberrations of this signaling pathway have been reported over time to be associated in NSCLC with different sensitivity to the EGFR tyrosine kinase inhibitors, to have a possible prognostic role and more recently HER2 amplification has been emerged as a possible mechanism in EGFR-mutated tumors of acquired resistance to the EGFR tyrosine kinase inhibitors. In addition, dysregulation of the HER2 pathway, in particular HER2 mutations (mostly, in-frame exon 20 insertions), may represent a possible novel therapeutic target in NSCLC, paving the way for a new generation of targeted agents in NSCLC. Since anecdotal case reports of clinical activity of anti-HER2 agents in NSCLC

  8. Mutations in the Kinase Domain of the HER2/ERBB2 Gene Identified in a Wide Variety of Human Cancers.

    PubMed

    Wen, Wenhsiang; Chen, Wangjuh Sting; Xiao, Nick; Bender, Ryan; Ghazalpour, Anatole; Tan, Zheng; Swensen, Jeffrey; Millis, Sherri Z; Basu, Gargi; Gatalica, Zoran; Press, Michael F

    2015-09-01

    The HER2 (official name ERBB2) gene encodes a membrane receptor in the epidermal growth factor receptor family amplified and overexpressed in adenocarcinoma. Activating mutations also occur in several cancers. We report mutation analyses of the HER2 kinase domain in 7497 histologically diverse cancers. Forty-five genes, including the kinase domain of HER2 with HER2 IHC and dual in situ hybridization, were analyzed in tumors from 7497 patients with cancer, including 850 breast, 770 colorectal, 910 non-small cell lung, 823 uterine or cervical, 1372 ovarian, and 297 pancreatic cancers, as well as 323 melanomas and 2152 other solid tumors. Sixty-nine HER2 kinase domain mutations were identified in tumors from 68 patients (approximately 1% of all cases, ranging from absent in sarcomas to 4% in urothelial cancers), which included previously published activating mutations and 13 novel mutations. Fourteen cases with coexisting HER2 mutation and amplification and/or overexpression were identified. Fifty-two of 68 patients had additional mutations in other analyzed genes, whereas 16 patients (23%) had HER2 mutations identified as the sole driver mutation. HER2 mutations coexisted with HER2 gene amplification and overexpression and with mutations in other functionally important genes. HER2 mutations were identified as the only driver mutation in a significant proportion of solid cancers. Evaluation of anti-HER2 therapies in nonamplified, HER2-mutated cancers is warranted. Copyright © 2015 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  9. HER2 Amplification and HER2 Mutation Are Distinct Molecular Targets in Lung Cancers.

    PubMed

    Li, Bob T; Ross, Dara S; Aisner, Dara L; Chaft, Jamie E; Hsu, Meier; Kako, Severine L; Kris, Mark G; Varella-Garcia, Marileila; Arcila, Maria E

    2016-03-01

    Human epidermal growth factor receptor 2 gene (HER2 [also known as ERBB2]) alterations have been identified as oncogenic drivers and potential therapeutic targets in lung cancers. The molecular associations of HER2 gene amplification, mutation, and HER2 protein overexpression in lung cancers have not been distinctly defined. To explore these associations, Memorial Sloan Kettering Cancer Center and the University of Colorado combined their data on HER2 alterations in lung cancers. Tumor specimens from 175 patients with lung adenocarcinomas and no prior targeted therapy were evaluated for the presence of HER2 amplification and mutation and HER2 protein overexpression. Amplification was assessed by fluorescence in situ hybridization (FISH) and defined as an HER2-to-chromosome enumeration probe 17 ratio of at least 2.0. Mutation was assessed by fragment analysis, mass spectrometry genotyping, and Sanger sequencing. Overexpression was assessed by immunohistochemical (IHC) staining. The frequencies of HER2 amplification and mutation and HER2 overexpression were calculated and their overlap examined. HER2 amplification was detected by FISH in 5 of 175 cases (3%). HER2 mutation was detected in 4 of 148 specimens (3%), including three identical 12-base pair insertions (p.A775_G776insYVMA) and a 9-base pair insertion, all in exon 20. None of the HER2-mutant cases was amplified. HER2 overexpression (2+ or 3+) on IHC staining was not detected in the 25 specimens available for testing, and negative IHC staining correlated with the negative results according to FISH. HER2 mutations are not associated with HER2 amplification, thus suggesting a distinct entity and therapeutic target. HER2-positive lung cancer may not be an adequate term, and patient cohorts for the study of HER2-targeted agents should be defined by the specific HER2 alteration present. Copyright © 2015 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

  10. HER2 loss in HER2-positive gastric or gastroesophageal cancer after trastuzumab therapy: Implication for further clinical research.

    PubMed

    Pietrantonio, F; Caporale, M; Morano, F; Scartozzi, M; Gloghini, A; De Vita, F; Giommoni, E; Fornaro, L; Aprile, G; Melisi, D; Berenato, R; Mennitto, A; Volpi, C C; Laterza, M M; Pusceddu, V; Antonuzzo, L; Vasile, E; Ongaro, E; Simionato, F; de Braud, F; Torri, V; Di Bartolomeo, M

    2016-12-15

    Mechanisms of acquired resistance to trastuzumab-based treatment in gastric cancer are largely unknown. In this study, we analyzed 22 pairs of tumor samples taken at baseline and post-progression in patients receiving chemotherapy and trastuzumab for advanced HER2-positive [immunohistochemistry (IHC) 3+ or 2+ with in-situ hybridization (ISH) amplification] gastric or gastroesophageal cancers. Strict clinical criteria for defining acquired trastuzumab resistance were adopted. Loss of HER2 positivity and loss of HER2 over-expression were defined as post-trastuzumab IHC score <3+ and absence of ISH amplification, and IHC "downscoring" from 2+/3+ to 0/1+, respectively. HER2 IHC was always performed, while ISH was missing in 3 post-progression samples. Patients with initial HER2 IHC score 3+ and 2+ were 14 (64%) and 8 (36%), respectively. Loss of HER2 positivity and HER2 over-expression was observed in 32 and 32% samples, respectively. The chance of HER2 loss was not associated with any of the baseline clinicopathological variables. The only exception was in patients with initial IHC score 2+ versus 3+, for both endpoints of HER2 positivity (80 vs. 14%; p = 0.008) and HER2 over-expression (63 vs. 14%; p = 0.025). As already shown in breast cancer, loss of HER2 may be observed also in gastric cancers patients treated with trastuzumab-based chemotherapy in the clinical practice. This phenomenon may be one of the biological reasons explaining the failure of anti-HER2 second-line strategies in initially HER2-positive disease. © 2016 UICC.

  11. Limiting the protein corona: A successful strategy for in vivo active targeting of anti-HER2 nanobody-functionalized nanostars.

    PubMed

    D'Hollander, Antoine; Jans, Hilde; Velde, Greetje Vande; Verstraete, Charlotte; Massa, Sam; Devoogdt, Nick; Stakenborg, Tim; Muyldermans, Serge; Lagae, Liesbet; Himmelreich, Uwe

    2017-04-01

    Gold nanoparticles hold great promise as anti-cancer theranostic agents against cancer by actively targeting the tumor cells. As this potential has been supported numerously during in vitro experiments, the effective application is hampered by our limited understanding and control of the interactions within complex in vivo biological systems. When these nanoparticles are exposed to a biological environment, their surfaces become covered with proteins and biomolecules, referred to as the protein corona, reducing the active targeting capabilities. We demonstrate a chemical strategy to overcome this issue by reducing the protein corona's thickness by blocking the active groups of the self-assembled monolayer on gold nanostars. An optimal blocking agent, 2-mercapto ethanol, has been selected based on charge and length of the carbon chain. By using a nanobody as a biological ligand of the human epidermal growth factor 2 receptor (HER2), the active targeting is demonstrated in vitro and in vivo in an experimental tumor model by using darkfield microscopy and photoacoustic imaging. In this study, we have established gold nanostars as a conceivable theranostic agent with a specificity for HER2-positive tumors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Novel anti-c-Mpl monoclonal antibodies identified multiple differentially glycosylated human c-Mpl proteins in megakaryocytic cells but not in human solid tumors.

    PubMed

    Zhan, Jinghui; Felder, Barbara; Ellison, Aaron R; Winters, Aaron; Salimi-Moosavi, Hossein; Scully, Sheila; Turk, James R; Wei, Ping

    2013-06-01

    Thrombopoietin and its cognate receptor, c-Mpl, are the primary molecular regulators of megakaryocytopoiesis and platelet production. To date the pattern of c-Mpl expression in human solid tumors and the distribution and biochemical properties of c-Mpl proteins in hematopoietic tissues are largely unknown. We have recently developed highly specific mouse monoclonal antibodies (MAb) against human c-Mpl. In this study we used these antibodies to demonstrate the presence of full-length and truncated human c-Mpl proteins in various megakaryocytic cell types, and their absence in over 100 solid tumor cell lines and in the 12 most common primary human tumor types. Quantitative assays showed a cell context-dependent distribution of full-length and truncated c-Mpl proteins. All forms of human c-Mpl protein were found to be modified with extensive N-linked glycosylation but different degrees of sialylation and O-linked glycosylation. Of note, different variants of full-length c-Mpl protein exhibiting differential glycosylation were expressed in erythromegakaryocytic leukemic cell lines and in platelets from healthy human donors. This work provides a comprehensive analysis of human c-Mpl mRNA and protein expression on normal and malignant hematopoietic and non-hematopoietic cells and demonstrates the multiple applications of several novel anti-c-Mpl antibodies.

  13. Validation of a new classifier for the automated analysis of the human epidermal growth factor receptor 2 (HER2) gene amplification in breast cancer specimens

    PubMed Central

    2013-01-01

    Amplification of the human epidermal growth factor receptor 2 (HER2) is a prognostic marker for poor clinical outcome and a predictive marker for therapeutic response to targeted therapies in breast cancer patients. With the introduction of anti-HER2 therapies, accurate assessment of HER2 status has become essential. Fluorescence in situ hybridization (FISH) is a widely used technique for the determination of HER2 status in breast cancer. However, the manual signal enumeration is time-consuming. Therefore, several companies like MetaSystem have developed automated image analysis software. Some of these signal enumeration software employ the so called “tile-sampling classifier”, a programming algorithm through which the software quantifies fluorescent signals in images on the basis of square tiles of fixed dimensions. Considering that the size of tile does not always correspond to the size of a single tumor cell nucleus, some users argue that this analysis method might not completely reflect the biology of cells. For that reason, MetaSystems has developed a new classifier which is able to recognize nuclei within tissue sections in order to determine the HER2 amplification status on nuclei basis. We call this new programming algorithm “nuclei-sampling classifier”. In this study, we evaluated the accuracy of the “nuclei-sampling classifier” in determining HER2 gene amplification by FISH in nuclei of breast cancer cells. To this aim, we randomly selected from our cohort 64 breast cancer specimens (32 nonamplified and 32 amplified) and we compared results obtained through manual scoring and through this new classifier. The new classifier automatically recognized individual nuclei. The automated analysis was followed by an optional human correction, during which the user interacted with the software in order to improve the selection of cell nuclei automatically selected. Overall concordance between manual scoring and automated nuclei-sampling analysis was 98

  14. Studies of the HER-2/neu proto-oncogene in human breast and ovarian cancer.

    PubMed

    Slamon, D J; Godolphin, W; Jones, L A; Holt, J A; Wong, S G; Keith, D E; Levin, W J; Stuart, S G; Udove, J; Ullrich, A

    1989-05-12

    Carcinoma of the breast and ovary account for one-third of all cancers occurring in women and together are responsible for approximately one-quarter of cancer-related deaths in females. The HER-2/neu proto-oncogene is amplified in 25 to 30 percent of human primary breast cancers and this alteration is associated with disease behavior. In this report, several similarities were found in the biology of HER-2/neu in breast and ovarian cancer, including a similar incidence of amplification, a direct correlation between amplification and over-expression, evidence of tumors in which overexpression occurs without amplification, and the association between gene alteration and clinical outcome. A comprehensive study of the gene and its products (RNA and protein) was simultaneously performed on a large number of both tumor types. This analysis identified several potential shortcomings of the various methods used to evaluate HER-2/neu in these diseases (Southern, Northern, and Western blots, and immunohistochemistry) and provided information regarding considerations that should be addressed when studying a gene or gene product in human tissue. The data presented further support the concept that the HER-2/neu gene may be involved in the pathogenesis of some human cancers.

  15. Anti-sphingosine-1-phosphate monoclonal antibodies inhibit angiogenesis and sub-retinal fibrosis in a murine model of laser-induced choroidal neovascularization

    PubMed Central

    Caballero, Sergio; Swaney, James; Moreno, Kelli; Afzal, Aqeela; Kielczewski, Jennifer; Stoller, Glenn; Cavalli, Amy; Garland, William; Hansen, Geneviève; Sabbadini, Roger; Grant, Maria B.

    2013-01-01

    The efficacy of novel monoclonal antibodies that neutralize the pro-angiogenic mediator, sphingosine-1-phosphate (S1P), were tested using in vitro and in vivo angiogenesis models, including choroidal neovascularization (CNV) induced by laser disruption of Bruch’s membrane. S1P receptor levels in human brain choroid plexus endothelial cells (CPEC), human lung microvascular endothelial cells, human retinal vascular endothelial cells, and circulating endothelial progenitor cells were examined by semi-quantitative PCR. The ability of murine or humanized anti-S1P monoclonal antibodies (mAbs) to inhibit S1P-mediated microvessel tube formation by CPEC on Matrigel was evaluated and capillary density in subcutaneous growth factor-loaded Matrigel plugs was determined following anti-S1P treatment. S1P promoted in vitro capillary tube formation in CPEC consistent with the presence of cognate S1P1–5 receptor expression by these cells and the S1P antibody induced a dose-dependent reduction in microvessel tube formation. In a murine model of laser-induced rupture of Bruch’s membrane, S1P was detected in posterior cups of mice receiving laser injury, but not in uninjured controls. Intravitreous injection of anti-S1P mAbs dramatically inhibited CNV formation and sub-retinal collagen deposition in all treatment groups (p < 0.05 compared to controls), thereby identifying S1P as a previously unrecognized mediator of angiogenesis and subretinal fibrosis in this model. These findings suggest that neutralizing S1P with anti-S1P mAbs may be a novel method of treating patients with exudative age-related macular degeneration by reducing angiogenesis and sub-retinal fibrosis, which are responsible for visual acuity loss in this disease. PMID:18723015

  16. Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kubota-Koketsu, Ritsuko; Mizuta, Hiroyuki; Oshita, Masatoshi

    2009-09-11

    Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizingmore » ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.« less

  17. Determination of HER2 status using both serum HER2 levels and circulating tumor cells in patients with recurrent breast cancer whose primary tumor was HER2 negative or of unknown HER2 status

    PubMed Central

    Fehm, Tanja; Becker, Sven; Duerr-Stoerzer, Silke; Sotlar, Karl; Mueller, Volkmar; Wallwiener, Diethelm; Lane, Nancy; Solomayer, Erich; Uhr, Jonathan

    2007-01-01

    Introduction At the time when metastatic disease is identified, assessment of human epidermal growth factor receptor (HER)2 status might help to optimize treatment decisions if HER2 status was not determined at first diagnosis and if HER2 positivity has been acquired during disease progression. Within this context, determination of serum HER2 or evaluation of HER2 status in circulating tumor cells (CTCs) may be of clinical relevance because metastatic tissue may be difficult to obtain for analysis as a result of its localization. The aim of this study was therefore to determine the HER2 status in serum and corresponding CTCs in patients with metastatic breast cancer whose primary tumors were HER2 negative or of unknown HER2 status. Methods Blood samples were obtained from 77 metastatic breast cancer patients with negative (n = 44) or unknown (n = 33) HER2 status. Serum HER2 was determined using a commercial HER2/neu ELISA kit. CTCs were detected by slide-based assay using immunomagnetic enrichment and characterized by phenotyping and genotyping. Alternatively, a commercial kit, based on RT-PCR, was used to detect and characterize CTCs. Results Twenty out of 77 patients with metastatic disease had elevated serum levels of HER2. Blood samples could be analyzed for the presence of CTCs in 67 patients. Eight out of 21 patients with detectable CTCs exhibited HER2 amplification. Twenty-three out of 77 patients were HER2 positive using at least one method. Concordance between HER2 status of CTCs and serum HER2 was observed in 15 of 21 patients (71%). In six patients conflicting results were obtained. Three patients with elevated serum HER2 status had HER2-negative CTCs, whereas three patients with HER2-positive CTCs had normal serum HER2 levels. Conclusion A subgroup of patients with initially negative or unknown HER2 status can have elevated serum HER2 levels and/or HER2-positive CTCs at the time of development of metastatic disease. Although only a small number of

  18. Induction of protective anti-CTL epitope responses against HER-2-positive breast cancer based on multivalent T7 phage nanoparticles.

    PubMed

    Pouyanfard, Somayeh; Bamdad, Taravat; Hashemi, Hamidreza; Bandehpour, Mojgan; Kazemi, Bahram

    2012-01-01

    We report here the development of multivalent T7 bacteriophage nanoparticles displaying an immunodominant H-2k(d)-restricted CTL epitope derived from the rat HER2/neu oncoprotein. The immunotherapeutic potential of the chimeric T7 nanoparticles as anti-cancer vaccine was investigated in BALB/c mice in an implantable breast tumor model. The results showed that T7 phage nanoparticles confer a high immunogenicity to the HER-2-derived minimal CTL epitope, as shown by inducing robust CTL responses. Furthermore, the chimeric nanoparticles protected mice against HER-2-positive tumor challenge in both prophylactic and therapeutic setting. In conclusion, these results suggest that CTL epitope-carrying T7 phage nanoparticles might be a promising approach for development of T cell epitope-based cancer vaccines.

  19. Induction of Protective Anti-CTL Epitope Responses against HER-2-Positive Breast Cancer Based on Multivalent T7 Phage Nanoparticles

    PubMed Central

    Pouyanfard, Somayeh; Bamdad, Taravat; Hashemi, Hamidreza; Bandehpour, Mojgan; Kazemi, Bahram

    2012-01-01

    We report here the development of multivalent T7 bacteriophage nanoparticles displaying an immunodominant H-2kd-restricted CTL epitope derived from the rat HER2/neu oncoprotein. The immunotherapeutic potential of the chimeric T7 nanoparticles as anti-cancer vaccine was investigated in BALB/c mice in an implantable breast tumor model. The results showed that T7 phage nanoparticles confer a high immunogenicity to the HER-2-derived minimal CTL epitope, as shown by inducing robust CTL responses. Furthermore, the chimeric nanoparticles protected mice against HER-2-positive tumor challenge in both prophylactic and therapeutic setting. In conclusion, these results suggest that CTL epitope-carrying T7 phage nanoparticles might be a promising approach for development of T cell epitope-based cancer vaccines. PMID:23166703

  20. Pharmacodynamics, pharmacokinetics and clinical efficacy of neratinib in HER2-positive breast cancer and breast cancer with HER2 mutations.

    PubMed

    Kourie, Hampig Raphael; Chaix, Marie; Gombos, Andrea; Aftimos, Phillippe; Awada, Ahmad

    2016-08-01

    Despite the availability of several potent HER2-directed targeted agents, primary and acquired resistance continues to influence patient outcomes in HER2-positive breast cancer. Neratinib is an irreversible pan-HER tyrosine kinase inhibitor in late-phase clinical development. This review article focuses on neratinib in the treatment of HER2-positive breast cancer - early and metastatic stage - and HER2-mutant breast cancer, with particular emphasis on the pharmacokinetics and pharmacodynamics of the drug. The phase III ExteNET trial shows that neratinib improves 2-year invasive disease-free survival after trastuzumab-based adjuvant therapy in early-stage HER2-positive breast cancer, and in particular HER2+/HR+ tumors. Survival data are awaited. The investigational role of neratinib in high-risk patients or conversely in de-escalation dual regimens with other anti-HER2 therapies and without chemotherapy are of interest. Phase II trials show that neratinib has efficacy, either as monotherapy or in combination with other chemotherapeutic or endocrine agents, in patients with HER2-positive metastatic breast cancer and in tumors harboring HER2 mutations. The role of neratinib in therapeutic algorithms of HER2-positive patients, as well as delaying CNS events, awaits the results of ongoing trials such as NALA. Diarrhea, the main toxicity of neratinib, can be effectively managed with early loperamide prophylaxis.

  1. Prolonged Response to Trastuzumab in a Patient With HER2-Nonamplified Breast Cancer With Elevated HER2 Dimerization Harboring an ERBB2 S310F Mutation.

    PubMed

    Chumsri, Saranya; Weidler, Jodi; Ali, Siraj; Balasubramanian, Sohail; Wallweber, Gerald; DeFazio-Eli, Lisa; Chenna, Ahmed; Huang, Weidong; DeRidder, Angela; Goicocheal, Lindsay; Perez, Edith A

    2015-09-01

    In the current genomic era, increasing evidence demonstrates that approximately 2% of HER2-negative breast cancers, by current standard testings, harbor activating mutations of ERBB2. However, whether patients with HER2-negative breast cancer with activating mutations of ERBB2 also experience response to anti-HER2 therapies remains unclear. This case report describes a patient with HER2-nonamplified heavily pretreated breast cancer who experienced prolonged response to trastuzumab in combination with pertuzumab and fulvestrant. Further molecular analysis demonstrated that her tumors had an elevated HER2 dimerization that corresponded to ERBB2 S310F mutation. Located in the extracellular domain of the HER2 protein, this mutation was reported to promote noncovalent dimerization that results in the activation of the downstream signaling pathways. This case highlights the fact that HER2-targeted therapy may be valuable in patients harboring an ERBB2 S310F mutation. Copyright © 2015 by the National Comprehensive Cancer Network.

  2. A Neutralizing Anti-gH/gL Monoclonal Antibody Is Protective in the Guinea Pig Model of Congenital CMV Infection

    PubMed Central

    Auerbach, Marcy R.; Yan, Donghong; Vij, Rajesh; Hongo, Jo-Anne; Nakamura, Gerald; Vernes, Jean-Michel; Meng, Y. Gloria; Lein, Samantha; Chan, Pamela; Ross, Jed; Carano, Richard; Deng, Rong; Lewin-Koh, Nicholas; Xu, Min; Feierbach, Becket

    2014-01-01

    Human cytomegalovirus (HCMV) is the most common cause of congenital virus infection. Congenital HCMV infection occurs in 0.2–1% of all births, and causes birth defects and developmental abnormalities, including sensorineural hearing loss and developmental delay. Several key studies have established the guinea pig as a tractable model for the study of congenital HCMV infection and have shown that polyclonal antibodies can be protective [1]–[3]. In this study, we demonstrate that an anti-guinea pig CMV (GPCMV) glycoprotein H/glycoprotein L neutralizing monoclonal antibody protects against fetal infection and loss in the guinea pig. Furthermore, we have delineated the kinetics of GPCMV congenital infection, from maternal infection (salivary glands, seroconversion, placenta) to fetal infection (fetus and amniotic fluid). Our studies support the hypothesis that a neutralizing monoclonal antibody targeting an envelope GPCMV glycoprotein can protect the fetus from infection and may shed light on the therapeutic intervention of HCMV congenital infection in humans. PMID:24722349

  3. Model-based Analysis of HER Activation in Cells Co-Expressing EGFR, HER2 and HER3.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shankaran, Harish; Zhang, Yi; Tan, Yunbing

    2013-08-22

    The HER/ErbB family of receptor tyrosine kinases drive critical responses in normal physiology and cancer, and the expression levels of the various HER receptors are critical determinants of clinical outcomes. HER activation is driven by the formation of various dimer complexes between members of this receptor family. The HER dimer types can have differential effects on downstream signaling and phenotypic outcomes. We constructed an integrated mathematical model of HER activation and trafficking to quantitatively link receptor expression levels to dimerization and activation. We parameterized the model with a comprehensive set of HER phosphorylation and abundance data collected in a panelmore » of human mammary epithelial cells expressing varying levels of EGFR, HER2 and HER3. Although parameter estimation yielded multiple solutions, predictions for dimer phosphorylation were in agreement with each other. We validated the model using experiments where pertuzumab was used to block HER2 dimerization. We used the model to predict HER dimerization and activation patterns in a panel of epithelial cells lines with known HER expression levels. Simulations over the range of expression levels seen in various cell lines indicate that: i) EGFR phosphorylation is driven by HER1/1 and HER1/2 dimers, and not HER1/3 dimers, ii) HER1/2 and HER2/3 dimers both contribute significantly to HER2 activation with the EGFR expression level determining the relative importance of these species, and iii) the HER2/3 dimer is largely responsible for HER3 activation. The model can be used to predict phosphorylated dimer levels for any given HER expression profile. This information in turn can be used to quantify the potencies of the various HER dimers, and can potentially inform personalized therapeutic approaches.« less

  4. Genetic heterogeneity in HER2 testing may influence therapy eligibility.

    PubMed

    Bernasconi, Barbara; Chiaravalli, Anna Maria; Finzi, Giovanna; Milani, Katia; Tibiletti, Maria Grazia

    2012-05-01

    Prospective studies have demonstrated that approximately 20% of HER2 testing may be inaccurate. When carefully validated testing is conducted, available data do not clearly demonstrate the superiority of either IHC or fluorescence in situ hybridization (FISH) as a predictor of benefit from anti-HER2 therapy. In addition, the interpretation of the findings of HER2 tests according to international guidelines is not uniform. The American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) recently published practice guidelines for a definition of HER2 amplification heterogeneity that can give rise to discrepant results between IHC and FISH assays for HER2. In this article, we compare the HER2 status of 291 non consecutive breast cancers. The status is determined by both IHC and FISH approaches, using a specific FISH strategy to investigate genetic heterogeneity. Our data demonstrate that HER2 amplified cells may be found as diffuse, clustered in a specific area or section, intermingled with non-amplified cells or confined to metastatic nodules. The correct evaluation of ratio value in the presence of genetic heterogeneity and of polysomy contributes to the accurate assessment of HER2 status and potentially affects the selection of appropriate anti-HER2 therapy. By taking into account the presence of different genetic cell populations, the immunotherapy eligibility criteria for HER2 FISH scoring proposed in the CAP (2009) and SIGU guidelines identify an additional subset of cases for trastuzumab or lapatinib therapy compared to the ASCO/CAP (2007) guidelines.

  5. Novel anti-Sialyl-Tn monoclonal antibodies and antibody-drug conjugates demonstrate tumor specificity and anti-tumor activity.

    PubMed

    Prendergast, Jillian M; Galvao da Silva, Ana Paula; Eavarone, David A; Ghaderi, Darius; Zhang, Mai; Brady, Dane; Wicks, Joan; DeSander, Julie; Behrens, Jeff; Rueda, Bo R

    Targeted therapeutics that can differentiate between normal and malignant tumor cells represent the ideal standard for the development of a successful anti-cancer strategy. The Sialyl-Thomsen-nouveau antigen (STn or Sialyl-Tn, also known as CD175s) is rarely seen in normal adult tissues, but it is abundantly expressed in many types of human epithelial cancers. We have identified novel antibodies that specifically target with high affinity the STn glycan independent of its carrier protein, affording the potential to recognize a wider array of cancer-specific sialylated proteins. A panel of murine monoclonal anti-STn therapeutic antibodies were generated and their binding specificity and efficacy were characterized in vitro and in in vivo murine cancer models. A subset of these antibodies were conjugated to monomethyl auristatin E (MMAE) to generate antibody-drug conjugates (ADCs). These ADCs demonstrated in vitro efficacy in STn-expressing cell lines and significant tumor growth inhibition in STn-expressing tumor xenograft cancer models with no evidence of overt toxicity.

  6. Antitumour effects of single or combined monoclonal antibodies directed against membrane antigens expressed by human B cells leukaemia

    PubMed Central

    2011-01-01

    Background The increasing availability of different monoclonal antibodies (mAbs) opens the way to more specific biologic therapy of cancer patients. However, despite the significant success of therapy in breast and ovarian carcinomas with anti-HER2 mAbs as well as in non-Hodkin B cell lymphomas with anti-CD20 mAbs, certain B cell malignancies such as B chronic lymphocytic leukaemia (B-CLL) respond poorly to anti-CD20 mAb, due to the low surface expression of this molecule. Thus, new mAbs adapted to each types of tumour will help to develop personalised mAb treatment. To this aim, we analyse the biological and therapeutic properties of three mAbs directed against the CD5, CD71 or HLA-DR molecules highly expressed on B-CLL cells. Results The three mAbs, after purification and radiolabelling demonstrated high and specific binding capacity to various human leukaemia target cells. Further in vitro analysis showed that mAb anti-CD5 induced neither growth inhibition nor apoptosis, mAb anti-CD71 induced proliferation inhibition with no early sign of cell death and mAb anti-HLA-DR induced specific cell aggregation, but without evidence of apoptosis. All three mAbs induced various degrees of ADCC by NK cells, as well as phagocytosis by macrophages. Only the anti-HLA-DR mAb induced complement mediated lysis. Coincubation of different pairs of mAbs did not significantly modify the in vitro results. In contrast with these discrete and heterogeneous in vitro effects, in vivo the three mAbs demonstrated marked anti-tumour efficacy and prolongation of mice survival in two models of SCID mice, grafted either intraperitoneally or intravenously with the CD5 transfected JOK1-5.3 cells. This cell line was derived from a human hairy cell leukaemia, a type of malignancy known to have very similar biological properties as the B-CLL, whose cells constitutively express CD5. Interestingly, the combined injection of anti-CD5 with anti-HLA-DR or with anti-CD71 led to longer mouse survival, as

  7. The reactivities of human erythrocyte autoantibodies anti-Pr2, anti-Gd, Fl and Sa with gangliosides in a chromatogram binding assay.

    PubMed Central

    Uemura, K; Roelcke, D; Nagai, Y; Feizi, T

    1984-01-01

    The thin layer chromatogram binding assay was used to study the reaction of several natural-monoclonal autoantibodies which recognize sialic acid-dependent antigens of human erythrocytes. Immunostaining of gangliosides derived from human and bovine erythrocytes was achieved with four autoantibodies designated anti-Pr2, anti-Gd, Sa and Fl, each of which has a different haemagglutination pattern with untreated and proteinase-treated erythrocytes and with cells of I and i antigen types. From the chromatogram binding patterns of anti-Pr2 with gangliosides of the neolacto and the ganglio series, it is deduced that this antibody reacts best with N-acetylneuraminic acid when it is alpha 2-3- or alpha 2-6-linked to a terminal Gal(beta 1-4)Glc/GlcNAc GlcNAc sequence and to a lesser extent when it is alpha 2-3-linked to a terminal Gal(beta 1-3)GalNAc sequence or to an internal galactose and when it is alpha 2-8-linked to another, internal N-acetylneuraminic acid residue. The other three antibodies differ from anti-Pr2 in their lack of reaction with glycolipids of the ganglio series. They react with the NeuAc(alpha 2-3)Gal(beta 1-4)Glc/GlcNAc sequence as found in GM3 and in glycolipids of the neolacto series, but show a preference for the latter, longer sequences. Thus all four antibodies react with sialylated oligosaccharides containing i type (linear) and I type (branched) neolacto backbones. Fl antibody differs from the other three in its stronger reaction with branched neolacto sequences in accordance with its stronger agglutination of erythrocytes of I rather than i type. The four antibodies show a specificity for N-acetyl- rather than N-glycolyl-neuraminic acid. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:6204642

  8. Synthesis, characterization, and biological verification of anti-HER2 indocyanine green-doxorubicin-loaded polyethyleneimine-coated perfluorocarbon double nanoemulsions for targeted photochemotherapy of breast cancer cells.

    PubMed

    Lee, Yu-Hsiang; Ma, Yun-Ting

    2017-05-18

    Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females worldwide. Among various types of breast cancer, the human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer is known to be more aggressive and often resistant to medicinal treatment, leading to an insufficient prognosis and poor susceptibility to chemotherapy and/or hormonal therapy in the current clinic. These circumstances implicate that developing an improved therapeutic strategy rather than persistently changing the anticancer drugs for trying is truly needed to successfully cure this type of breast cancer. In this study, we aimed to fabricate anti-HER2 indocyanine green (ICG)-doxorubicin (DOX)-loaded polyethyleneimine-coated perfluorocarbon double nanoemulsions (HIDPPDNEs) to explore the co-administration of phototherapy and chemotherapy for HER2-overexpressing breast cancer in vitro. The HIDPPDNE was first characterized as a sphere-like nanoparticle with surface charge of -57.1 ± 5.6 mV and size of 340.6 ± 4.5 nm, whereas the DOX release rates for the nanodroplets within 48 h in 4 and 37 °C were obtained by 8.13 ± 2.46% and 19.88 ± 2.75%, respectively. We then examined the target-ability of the nanostructure and found that the adhesion efficiency of the HIDPPDNEs onto HER2+ MDA-MB-453 cells was threefold higher than the nanodroplets without anti-HER2 antibody, indicating that the HIDPPDNEs are the product with HER2 binding specificity. In comparison to freely dissolved ICG, the HIDPPDNEs conferred an enhanced thermal stability to the entrapped ICG, and were able to provide a comparable hyperthermia effect and markedly increased production of singlet oxygen under near infrared irradiation (808 nm; 6 W/cm 2 ). Based on the viability analyses, the results showed that the HIDPPDNEs were effective on cell eradication upon near infrared irradiation (808 nm; 6 W/cm 2 ), and the resulting cell mortality was even higher

  9. Generation and characterization of anti-MUC4 monoclonal antibodies reactive with normal and cancer cells in humans.

    PubMed

    Moniaux, Nicolas; Varshney, Grish Chandra; Chauhan, Subhash Chand; Copin, Marie Christine; Jain, Maneesh; Wittel, Uwe A; Andrianifahanana, Mahefatiana; Aubert, Jean-Pierre; Batra, Surinder Kumar

    2004-02-01

    We have previously cloned the full-length cDNA (approximately 28 Kb) and established the complete genomic organization (25 exons/introns over 100 kb) of the human MUC4 mucin. This large molecule is predicted to protrude over 2 microm above the cell surface, in which MUC4alpha is an extracellular mucin-type glycoprotein subunit and MUC4beta is the transmembrane subunit. Over two thirds of the encoded protein sequence consists of 16-amino-acid tandem repeats (TR), which are flanked by unique sequences. In this study we generated and characterized monoclonal antibodies (MAbs) directed against the TR region of MUC4. Mice were immunized with a KLH-conjugated MUC4 TR peptide, STGDTTPLPVTDTSSV. Several clones were purified by three rounds of limited dilutions and stable clones presenting a sustained antibody production were selected for subsequent characterization. Antibodies were tested for their reactivity and specificity to recognize the MUC4 peptide and further screened by enzyme-linked immunosorbent assay (ELISA) and Western blotting analyses. One of the MAbs (8G7) was strongly reactive against the MUC4 peptide and with native MUC4 from human tissues or pancreatic cancer cells in Western blotting, immunohistochemistry, and confocal analysis. Anti-MUC4 MAb may represent a powerful tool for the study of MUC4 function under normal and pathological conditions and for diagnosis of solid tumors including those in the breast, pancreas, lungs, and ovaries.

  10. Enzyme-linked immunosorbent assay for total sennosides using anti-sennside A and anti-sennoside B monoclonal antibodies.

    PubMed

    Morinaga, Osamu; Uto, Takuhiro; Sakamoto, Seiichi; Tanaka, Hiroyuki; Shoyama, Yukihiro

    2009-01-01

    Total sennosides concentration is a very important factor when rhubarb and senna will be used as crude drugs. However, one-step analytical technique for total sennosides has not been reported except HPLC. An enzyme-linked immunosorbent assay (ELISA) for total sennosides concentration by using the combination of anti-sennoside A (SA) and anti-sennoside B (SB) monoclonal antibodies (MAbs) in a single assay has been investigated. Total sennosides concentration in rhubarb and senna samples determined by newly developed assay system showed good agreement with those analyzed by ELISA using anti-SA MAb and anti-SB MAb, respectively.

  11. Efficacy and safety of treatment with an anti-m2e monoclonal antibody in experimental human influenza.

    PubMed

    Ramos, Eleanor L; Mitcham, Jennifer L; Koller, Teri D; Bonavia, Aurelio; Usner, Dale W; Balaratnam, Ganesh; Fredlund, Paul; Swiderek, Kristine M

    2015-04-01

    The efficacy of TCN-032, a human monoclonal antibody targeting a conserved epitope on M2e, was explored in experimental human influenza. Healthy volunteers were inoculated with influenza A/Wisconsin/67/2005 (H3N2) and received a single dose of the study drug, TCN-032, or placebo 24 hours later. Subjects were monitored for symptoms, viral shedding, and safety, including cytokine measurements. Oseltamivir was administered 7 days after inoculation. Although the primary objective of reducing the proportion of subjects developing any grade ≥2 influenza symptom or pyrexia, was not achieved, TCN-032-treated subjects showed 35% reduction (P = .047) in median total symptom area under the curve (days 1-7) and 2.2 log reduction in median viral load area under the curve (days 2-7) by quantitative polymerase chain reaction (P = .09) compared with placebo-treated subjects. TCN-032 was safe and well tolerated with no additional safety signals after administration of oseltamivir. Serum cytokine levels (interferon γ, tumor necrosis factor α, and interleukin 8 and 10) were similar in both groups. Genotypic and phenotypic analyses showed no difference between virus derived from subjects after TCN-032 treatment and parental strain. These data indicate that TCN-032 may provide immediate immunity and therapeutic benefit in influenza A infection, with no apparent emergence of resistant virus. TCN-032 was safe with no evidence of immune exacerbation based on serum cytokine expression. Clinicaltrials.gov registry number. NCT01719874. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Demonstration of monoclonal anti-carcinoembryonic antigen (CEA) antibody internalization by electron microscopy, western blotting and radioimmunoassay.

    PubMed

    Tsaltas, G; Ford, C H; Gallant, M

    1992-01-01

    One of the important factors affecting the action of monoclonal antibodies (Mabs) or immunoconjugates on tumour sites depends on whether the Mab is internalized by the cancer cells in question. The underexplored subject of internalization is discussed in this paper, and a number of in vitro techniques for investigating internalization are evaluated, using a model which consists of a well characterized anti-carcinoembryonic antigen (anti-CEA) Mab and a number of CEA expressing human cancer cell lines. Employing two alternative radiolabeling assays, evidence for internalization of the anti-CEA Mab by a CEA-positive colorectal cancer cell line (LS174T) was obtained throughout the time intervals examined (5 min to 150 min). Electronmicroscopy employing horseradish-peroxidase labeled anti-CEA Mab and control antibody permitted direct visualization of anti-CEA Mab-related staining in intracellular compartments of a high CEA-expressor human colorectal cell line (SKCO1). Finally Western blots of samples derived from cytosolic and membrane components of solubilized cells from lung and colonic cancer cell lines provided evidence for internalized anti-CEA Mab throughout seven half hour intervals, starting at 5 minutes. Internalized anti-CEA was detected in all CEA expressing cell lines (LS174T, SKCO1, BENN) but not in the case of a very low CEA expressor line (COLO 320).

  13. Mouse monoclonal antibodies against human c-Mpl and characterization for flow cytometry applications.

    PubMed

    Abbott, Christina; Huang, Guo; Ellison, Aaron R; Chen, Ching; Arora, Taruna; Szilvassy, Stephen J; Wei, Ping

    2010-04-01

    Mouse monoclonal antibodies (MAbs) against human c-Mpl, the cognate receptor for thrombopoietin (TPO), were generated using hybridoma technology and characterized by various assays to demonstrate their specificity and affinity. Two such MAbs, 1.6 and 1.75, were determined to be superior for flow cytometry studies and exhibited double-digit picomolar (pM) affinities to soluble human c-Mpl protein. Both MAbs specifically bound to cells engineered to overexpress human c-Mpl protein, immortalized human hematopoietic cell lines that express endogenous c-Mpl, primary human bone marrow and peripheral blood-derived CD34(+) cells, and purified human platelets. No binding was detected on cell lines that did not express c-Mpl. Receptor competition and siRNA knock-down studies further confirmed the specificity of antibodies 1.6 and 1.75 for human c-Mpl. In contrast to these newly generated MAbs, none of eight commercially available anti-c-Mpl antibodies tested were found to bind specifically to human c-Mpl and were thus shown to be unsuitable for flow cytometry studies. Monoclonal antibodies 1.6 and 1.75 will therefore be useful flow cytometry reagents to detect cell surface c-Mpl expression.

  14. Bone marrow transplantation across major histocompatibility barriers. V. Protection of mice from lethal graft-vs. -host disease by pretreatment of donor cells with monoclonal anti-Thy-1. 2 coupled to the toxin ricin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vallera, D.A.; Youle, R.J.; Neville, D.M. Jr.

    1982-03-01

    A new method has been devised to eliminate T cells from murine bone marrow grafts across major histocompatibility barriers and thus prevent graft-vs.-host disease (GVHD). The method utilizes a monoclonal antibody directed at the Thy-1.2 antigen but is complement independent. To make anti-Thy-1.2 toxic, the antibody is covalently linked to the toxin ricin. Ricin ordinarily binds, enters, and kills cells through receptors containing galactose. The hybrid protein, anti-Thy-1.2-ricin, can enter and kill cells via the Thy-1.2 receptor. In the presence of lactose the usual entry route for ricin is largely blocked and the hybrid is shown to be a highlymore » selective reagent that is T cell specific in its inhibition of mitogen-stimulated splenocytes. We have used a model of severe and fatal GVHD where BALB/c splenocytes and bone marrow cells are given to irradiated C57BL/6 recipients. Over 90% of these mice die by day 70, exhibiting signs of GVHD. When donor cells are pretreated with 0.5 microgram/ml of anti-Thy-1.2-ricin plus 200 mM lactose before injection, 10 of 11 animals survive through day 70 without signs of GVHD. These studies demonstrate that ricin linked to monoclonal antibodies may have utility related to the prevention of GVHD in human bone marrow transplantation.« less

  15. Comparative Evaluation of Anti-HER2 Affibody Molecules Labeled with 64Cu Using NOTA and NODAGA

    PubMed Central

    Yim, Cheng-Bin; Rajander, Johan; Perols, Anna; Karlström, Amelie Eriksson; Haaparanta-Solin, Merja; Grönroos, Tove J.; Solin, Olof; Orlova, Anna

    2017-01-01

    Imaging using affibody molecules enables discrimination between breast cancer metastases with high and low expression of HER2, making appropriate therapy selection possible. This study aimed to evaluate if the longer half-life of 64Cu (T1/2 = 12.7 h) would make 64Cu a superior nuclide compared to 68Ga for PET imaging of HER2 expression using affibody molecules. The synthetic ZHER2:S1 affibody molecule was conjugated with the chelators NOTA or NODAGA and labeled with 64Cu. The tumor-targeting properties of 64Cu-NOTA-ZHER2:S1 and 64Cu-NODAGA-ZHER2:S1 were evaluated and compared with the targeting properties of 68Ga-NODAGA-ZHER2:S1 in mice. Both 64Cu-NOTA-ZHER2:S1 and 64Cu-NODAGA-ZHER2:S1 demonstrated specific targeting of HER2-expressing xenografts. At 2 h after injection of 64Cu-NOTA-ZHER2:S1, 64Cu-NODAGA-ZHER2:S1, and 68Ga-NODAGA-ZHER2:S1, tumor uptakes did not differ significantly. Renal uptake of 64Cu-labeled conjugates was dramatically reduced at 6 and 24 h after injection. Notably, radioactivity uptake concomitantly increased in blood, lung, liver, spleen, and intestines, which resulted in decreased tumor-to-organ ratios compared to 2 h postinjection. Organ uptake was lower for 64Cu-NODAGA-ZHER2:S1. The most probable explanation for this biodistribution pattern was the release and redistribution of renal radiometabolites. In conclusion, monoamide derivatives of NOTA and NODAGA may be suboptimal chelators for radiocopper labeling of anti-HER2 affibody molecules and, possibly, other scaffold proteins with high renal uptake. PMID:29097939

  16. Perspectives of HER2-targeting in gastric and esophageal cancer.

    PubMed

    Gerson, James N; Skariah, Sam; Denlinger, Crystal S; Astsaturov, Igor

    2017-05-01

    The blockade of HER2 signaling has significantly improved the outlook for esophagogastric cancer patients. However, targeting HER2 still remains challenging due to complex biology of this receptor in gastric and esophageal cancers. Areas covered: Here, we review complex HER2 biology, current methods of HER2 testing and tumor heterogeneity of gastroesophageal cancer. Ongoing and completed clinical research data are discussed. Expert opinion: HER2 overexpression is a validated target in gastroesophageal cancer, with therapeutic implications resulting in prolonged survival when inhibited in the front-line setting. With standardized HER2 testing in gastro-esophageal cancer, the ongoing trials are testing newer agents and combinations including combination of anti-HER2 antibodies with immunotherapy. Clonal heterogeneity and emergence of resistance will challenge our approach to treating these patients beyond the frontline settings.

  17. Monitoring therapeutic response of human ovarian cancer to trastuzumab by SPECT imaging with (99m)Tc-peptide-Z(HER2:342).

    PubMed

    Zhang, Jingmian; Zhao, Xinming; Wang, Shijie; Wang, Na; Han, Jingya; Jia, Lizhuo; Ren, Xiuchun

    2015-06-01

    Patients with human epidermal growth factor receptor 2 (HER2)-positive cancer are candidates for treatment with the anti-HER2 antibody trastuzumab. How to systemically assess tumor HER2 expression and identifying appropriate use of anti-HER2 therapies by noninvasive imaging in vivo is an urgent issue. The purpose of this study was to evaluate SPECT imaging of (99m)Tc-Gly-(D)Ala-Gly-Gly-Z(HER2:342) ((99m)Tc-peptide-Z(HER2:342)) for monitoring therapeutic response to trastuzumab in nude mice bearing HER2-positive SKOV-3 xenografts. Nude mice bearing HER2-positive SKOV-3 xenografts were treated with trastuzumab (treatment group) or saline (control) with ten mice in each group. Mice in trastuzumab-treated group were given trastuzumab intraperiotoneally 4 mg/kg on day 1 and 2 mg/kg on day 8; Mice in control group were given physiological saline on day 1 and 8. Mice body weights and tumour volume were monitored every three days during treatment. In vivo SPECT imaging was performed in mice of the two groups using (99m)Tc-peptide-Z(HER2:342) before treatment, on day 8 and 15 after treatment. Radiolabeled probe uptake in tumours was measured as the ratio of radioactive counts in the tumour to that in the contralateral equivalent region (T/NT). After SPECT imaging on day 15, all the mice were euthanized, biodistribution studies of the SKOV-3 xenografts were carried out to validate the imaging results and HER2 expression of the transplanted tumours was analyzed by immunohistochemistry (IHC). Correlation analysis was performed between T/NT ratios acquired by in vivo SPECT imaging on day 15 and the HER2 level of tumours. In vitro cell binding capacity of (99m)Tc-Z(HER2:342) with SKOV-3 cells in the absence and presence of varying amount of trastuzumab were also conducted in the study. Twenty mice body weight in the two groups gradually increased during treatment, but there was no statistical difference (p > 0.05). Though volumes of SKOV-3 xenografts gradually increased in each

  18. Influence of Alternative Tubulin Inhibitors on the Potency of a Epirubicin-Immunochemotherapeutic Synthesized with an Ultra Violet Light-Activated Intermediate: Influence of incorporating an internal/integral disulfide bond structure and Alternative Tubulin/Microtubule Inhibitors on the Cytotoxic Anti-Neoplastic Potency of Epirubicin-(C3-amide)-Anti-HER2/neu Synthesized Utilizing a UV-Photoactivated Anthracycline Intermediate.

    PubMed

    Coyne, C P; Jones, Toni; Bear, Ryan

    2012-11-01

    Immunochemotherapeutics, epirubicin-(C 3 - amide )-SS-[anti-HER2/ neu ] with an internal disulfide bond, and epirubicin-(C 3 - amide )-[anti-HER2/ neu ] were synthesized utilizing succinimidyl 2-[(4,4'-azipentanamido) ethyl]-1,3'-dithioproprionate or succinimidyl 4,4-azipentanoate respectively. Western blot analysis was used to determine the presence of any immunoglobulin fragmentation or IgG-IgG polymerization. Retained HER2/ neu binding characteristics of epirubicin-(C 3 - amide )-[anti-HER2/ neu ] and epirubicin-(C 3 - amide )-SS-[anti-HER2/ neu ] were validated by cell-ELISA using a mammary adenocarcinoma (SKBr-3) population that highly over-expresses trophic HER2/ neu receptor complexes. Cytotoxic anti-neoplastic potency of epirubicin-(C 3 - amide )-[anti-HER2/ neu ] and epirubicin-(C 3 - amide )-SS-[anti-HER2/ neu ] between epirubicin-equivalent concentrations of 10 -10 M and 10 -6 M was determined by measuring the vitality/proliferation of chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3 cell type). Cytotoxic anti-neoplastic potency of benzimidazoles (albendazole, flubendazole, membendazole) and griseofulvin were assessed between 0-to-2 μg/ml and 0-to-100 μg/ml respectively while mebendazole and griseofulvin were analyzed at fixed concentrations of 0.35 μg/ml and 35 g/ml respectively in dual combination with gradient concentrations of epirubicin-(C 3 - amide )-[anti-HER2/ neu ] and epirubicin-(C 3 - amide )-SS-[anti-HER2/ neu ]. Cytotoxic anti-neoplastic potency for epirubicin-(C 3 - amide )-[anti-HER2/ neu ] and epirubicin-(C 3 - amide )-SS-[anti-HER2/ neu ] against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) was nearly identical at epirubicin-equivalent concentrations of 10 -10 M and 10 -6 M. The benzimadazoles also possessed cytotoxic anti-neoplastic activity with flubendazole and albendazole being the most and least potent respectively. Similarly, griseofulvin had cytotoxic anti-neoplastic activity and was more potent than

  19. Blockade of human P2X7 receptor function with a monoclonal antibody.

    PubMed

    Buell, G; Chessell, I P; Michel, A D; Collo, G; Salazzo, M; Herren, S; Gretener, D; Grahames, C; Kaur, R; Kosco-Vilbois, M H; Humphrey, P P

    1998-11-15

    A monoclonal antibody (MoAb) specific for the human P2X7 receptor was generated in mice. As assessed by flow cytometry, the MoAb labeled human blood-derived macrophage cells natively expressing P2X7 receptors and cells transfected with human P2X7 but not other P2X receptor types. The MoAb was used to immunoprecipitate the human P2X7 receptor protein, and in immunohistochemical studies on human lymphoid tissue, P2X7 receptor labeling was observed within discrete areas of the marginal zone of human tonsil sections. The antibody also acted as a selective antagonist of human P2X7 receptors in several functional studies. Thus, whole cell currents, elicited by the brief application of 2',3'-(4-benzoyl)-benzoyl-ATP in cells expressing human P2X7, were reduced in amplitude by the presence of the MoAb. Furthermore, preincubation of human monocytic THP-1 cells with the MoAb antagonized the ability of P2X7 agonists to induce the release of interleukin-1beta.

  20. Anti-claudin 18.2 antibody as new targeted therapy for advanced gastric cancer.

    PubMed

    Singh, Prabhsimranjot; Toom, Sudhamshi; Huang, Yiwu

    2017-05-12

    Targeted therapy and immunotherapy have revolutionized treatment of various cancers in the past decade. Despite targeted therapy with trastuzumab in Her2-positive gastric cancer patients, survival has been dismal, mostly due to disease progression and toxicity related to the treatments. One area of active development is looking for ideal monoclonal antibodies (IMAB) specific to the proteins only on the tumor and hence avoiding unnecessary side effects. Claudin proteins with isoform 2 are one such protein, specific for several cancers, particularly gastric cancer and its metastases, leading to the development of anti-claudin 18.2 specific antibody, claudiximab. This review will highlight the latest development of claudiximab as first in class IMAB for the treatment of gastric cancer.

  1. Paraneoplastic cerebellar degeneration with anti-Yo antibody in a patient with HER2/neu overexpressing breast cancer: a case report with a current literature review.

    PubMed

    Ogita, Shin; Llaguna, Omar H; Feldman, Sheldon M; Blum, Ronald

    2008-01-01

    Paraneoplastic cerebellar degeneration (PCD) is a rare paraneoplastic syndrome, occurring in <1% of breast cancers. We describe a 32-year-old female presenting with ataxia subsequently diagnosed with poorly differentiated breast cancer. She was serum anti-Yo antibody positive, with estrogen/progesterone receptor negative and HER2/neu receptor positive breast cancer. Neurological symptoms progressed despite modified radical mastectomy, supraclavicular lymphadenectomy, intravenous immunoglobulin, corticosteroids, transtuzumab, and combination chemotherapy. We performed a literature search, which found a possible association between anti-Yo positive PCD and HER2/neu-expressing breast cancer.

  2. Anti-Podocalyxin Monoclonal Antibody 47-mG2a Detects Lung Cancers by Immunohistochemistry.

    PubMed

    Yamada, Shinji; Itai, Shunsuke; Kaneko, Mika K; Kato, Yukinari

    2018-04-01

    Lung cancer is one of the leading causes of cancer-related deaths in the world. Regardless of the advances in lung cancer treatments, the prognosis is still poor. Podocalyxin (PODXL) is a highly glycosylated type I transmembrane protein that is expressed in normal tissues, including the heart, pancreas, and breast. It is also found and used as a diagnostic marker in many cancers, such as renal, brain, breast, oral, and lung cancers. We previously developed specific and sensitive anti-PODXL monoclonal antibodies, PcMab-47 (mouse IgG 1 , kappa) and its mouse IgG 2a -type (47-mG 2a ), both of which were suitable for immunohistochemical analyses of oral cancers. In this study, we investigated the utility of PcMab-47 and 47-mG 2a for the immunohistochemical analyses of lung cancers. PcMab-47 stained 51/70 (72.9%) cases of lung cancer, whereas 47-mG 2a stained 59/70 (84.3%) cases, indicating that the latter antibody is more sensitive and is useful for detecting PODXL in lung cancers.

  3. Bystander killing effect of DS-8201a, a novel anti-human epidermal growth factor receptor 2 antibody-drug conjugate, in tumors with human epidermal growth factor receptor 2 heterogeneity.

    PubMed

    Ogitani, Yusuke; Hagihara, Katsunobu; Oitate, Masataka; Naito, Hiroyuki; Agatsuma, Toshinori

    2016-07-01

    Antibody-drug conjugates deliver anticancer agents selectively and efficiently to tumor tissue and have significant antitumor efficacy with a wide therapeutic window. DS-8201a is a human epidermal growth factor receptor 2 (HER2)-targeting antibody-drug conjugate prepared using a novel linker-payload system with a potent topoisomerase I inhibitor, exatecan derivative (DX-8951 derivative, DXd). It was effective against trastuzumab emtansine (T-DM1)-insensitive patient-derived xenograft models with both high and low HER2 expression. In this study, the bystander killing effect of DS-8201a was evaluated and compared with that of T-DM1. We confirmed that the payload of DS-8201a, DXd (1), was highly membrane-permeable whereas that of T-DM1, Lys-SMCC-DM1, had a low level of permeability. Under a coculture condition of HER2-positive KPL-4 cells and negative MDA-MB-468 cells in vitro, DS-8201a killed both cells, whereas T-DM1 and an antibody-drug conjugate with a low permeable payload, anti-HER2-DXd (2), did not. In vivo evaluation was carried out using mice inoculated with a mixture of HER2-positive NCI-N87 cells and HER2-negative MDA-MB-468-Luc cells by using an in vivo imaging system. In vivo, DS-8201a reduced the luciferase signal of the mice, indicating suppression of the MDA-MB-468-Luc population; however, T-DM1 and anti-HER2-DXd (2) did not. Furthermore, it was confirmed that DS-8201a was not effective against MDA-MB-468-Luc tumors inoculated at the opposite side of the NCI-N87 tumor, suggesting that the bystander killing effect of DS-8201a is observed only in cells neighboring HER2-positive cells, indicating low concern in terms of systemic toxicity. These results indicated that DS-8201a has a potent bystander effect due to a highly membrane-permeable payload and is beneficial in treating tumors with HER2 heterogeneity that are unresponsive to T-DM1. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer

  4. A novel rabbit anti-hepatocyte growth factor monoclonal neutralizing antibody inhibits tumor growth in prostate cancer cells and mouse xenografts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Yanlan; Chen, Yicheng; Ding, Guoqing

    The hepatocyte growth factor and its receptor c-Met are correlated with castration-resistance in prostate cancer. Although HGF has been considered as an attractive target for therapeutic antibodies, the lack of cross-reactivity of monoclonal antibodies with human/mouse HGFs is a major obstacle in preclinical developments. We generated a panel of anti-HGF RabMAbs either blocking HGF/c-Met interaction or inhibiting c-Met phosphorylation. We selected one RabMAb with mouse cross-reactivity and demonstrated that it blocked HGF-stimulated downstream activation in PC-3 and DU145 cells. Anti-HGF RabMAb inhibited not only the growth of PC-3 cells but also HGF-dependent proliferation in HUVECs. We further demonstrated the efficacymore » and potency of the anti-HGF RabMAb in tumor xenograft mice models. Through these in vitro and in vivo experiments, we explored a novel therapeutic antibody for advanced prostate cancer. - Highlights: • HGF is an attractive target for castration-refractory prostate cancer. • We generated and characterized a panel of anti-HGF rabbit monoclonal antibodies. • More than half of these anti-HGF RabMAbs was cross-reactive with mouse HGF. • Anti-HGF RabMAb blocks HGF-stimulated phosphorylation and cell growth in vitro. • Anti-HGF RabMAb inhibits tumor growth and angiogenesis in xenograft mice.« less

  5. Lapatinib with trastuzumab for HER2-positive early breast cancer (NeoALTTO): a randomised, open-label, multicentre, phase 3 trial

    PubMed Central

    Baselga, José; Bradbury, Ian; Eidtmann, Holger; Di Cosimo, Serena; de Azambuja, Evandro; Aura, Claudia; Gómez, Henry; Dinh, Phuong; Fauria, Karine; Van Dooren, Veerle; Aktan, Gursel; Goldhirsch, Aron; Chang, Tsai-Wang; Horváth, Zsolt; Coccia-Portugal, Maria; Domont, Julien; Tseng, Ling-Min; Kunz, Georg; Sohn, Joo Hyuk; Semiglazov, Vladimir; Lerzo, Guillermo; Palacova, Marketa; Probachai, Volodymyr; Pusztai, Lajos; Untch, Michael; Gelber, Richard D; Piccart-Gebhart, Martine

    2017-01-01

    Summary Background The anti-HER2 monoclonal antibody trastuzumab and the tyrosine kinase inhibitor lapatinib have complementary mechanisms of action and synergistic antitumour activity in models of HER2-overexpressing breast cancer. We argue that the two anti-HER2 agents given together would be better than single-agent therapy. Methods In this parallel groups, randomised, open-label, phase 3 study undertaken between Jan 5, 2008, and May 27, 2010, women from 23 countries with HER2-positive primary breast cancer with tumours greater than 2 cm in diameter were randomly assigned to oral lapatinib (1500 mg), intravenous trastuzumab (loading dose 4 mg/kg, subsequent doses 2 mg/kg), or lapatinib (1000 mg) plus trastuzumab. Treatment allocation was by stratified, permuted blocks randomisation, with four stratification factors. Anti-HER2 therapy alone was given for the first 6 weeks; weekly paclitaxel (80 mg/m2) was then added to the regimen for a further 12 weeks, before definitive surgery was undertaken. After surgery, patients received adjuvant chemotherapy followed by the same targeted therapy as in the neoadjuvant phase to 52 weeks. The primary endpoint was the rate of pathological complete response (pCR), analysed by intention to treat. This trial is registered with ClinicalTrials.gov, NCT00553358. Findings 154 patients received lapatinib, 149 trastuzumab, and 152 the combination. pCR rate was significantly higher in the group given lapatinib and trastuzumab (78 of 152 patients [51·3%; 95% CI 43·1–59·5]) than in the group given trastuzumab alone (44 of 149 patients [29·5%; 22·4–37·5]; difference 21·1%, 9·1–34·2, p=0·0001). We recorded no significant difference in pCR between the lapatinib (38 of 154 patients [24·7%, 18·1–32·3]) and the trastuzumab (difference −4·8%, −17·6 to 8·2, p=0·34) groups. No major cardiac dysfunctions occurred. Frequency of grade 3 diarrhoea was higher with lapatinib (36 patients [23·4%]) and lapatinib plus

  6. Detecting fish parvalbumin with commercial mouse monoclonal anti-frog parvalbumin IgG.

    PubMed

    Chen, Lingyun; Hefle, Sue L; Taylor, Steve L; Swoboda, Ines; Goodman, Richard E

    2006-07-26

    Parvalbumin is a calcium-binding muscle protein that is highly conserved across fish species and amphibians. It is the major cross-reactive allergen associated with both fish and frog allergy. We used two-dimensional electrophoretic and immunoblotting techniques to investigate the utility of a commercial monoclonal anti-frog parvalbumin IgG for detecting parvalbumin present in some commonly consumed fish species. The 2D electrophoresis and immunoblots revealed species-specific differences in proteins that appear to represent various numbers of isoforms of parvalbumin in carp (5), catfish (3), cod (1) and tilapia (2). No parvalbumin was detected in yellowfin tuna. Based on minor differences in relative intensities of protein staining and immunodetection, parvalbumin isoforms may have slight differences in the epitope region recognized by the anti-frog parvalbumin antibody. These results suggest that the frog anti-parvalbumin antibody can be used as a valuable tool to detect parvalbumins from the fish tested in this study, except yellowfin tuna.

  7. Detection of the Argonaute Protein Ago2 and microRNAs in the RNA Induced Silencing Complex (RISC) Using a Monoclonal Antibody

    PubMed Central

    Ikeda, Keigo; Satoh, Minoru; Pauley, Kaleb M.; Fritzler, Marvin J.; Reeves, Westley H.; Chan, Edward K.L.

    2007-01-01

    MicroRNAs (miRNAs) are short RNA molecules responsible for post-transcriptional gene silencing by the degradation or translational inhibition of their target messenger RNAs (mRNAs). This process of gene silencing, known as RNA interference (RNAi), is mediated by highly conserved Argonaute (Ago) proteins which are the key components of the RNA induced silencing complex (RISC). In humans, Ago2 is responsible for the endonuclease cleavage of targeted mRNA and it interacts with the mRNA-binding protein GW182, which is a marker for cytoplasmic foci referred to as GW bodies (GWBs). We demonstrated that the anti-Ago2 monoclonal antibody 4F9 recognized GWBs in a cell cycle dependent manner and was capable of capturing miRNAs associated with Ago2. Since Ago2 protein is the effector protein of RNAi, anti-Ago2 monoclonal antibody may be useful in capturing functional miRNAs. PMID:17054975

  8. Detection of the argonaute protein Ago2 and microRNAs in the RNA induced silencing complex (RISC) using a monoclonal antibody.

    PubMed

    Ikeda, Keigo; Satoh, Minoru; Pauley, Kaleb M; Fritzler, Marvin J; Reeves, Westley H; Chan, Edward K L

    2006-12-20

    MicroRNAs (miRNAs) are short RNA molecules responsible for post-transcriptional gene silencing by the degradation or translational inhibition of their target messenger RNAs (mRNAs). This process of gene silencing, known as RNA interference (RNAi), is mediated by highly conserved Argonaute (Ago) proteins which are the key components of the RNA induced silencing complex (RISC). In humans, Ago2 is responsible for the endonuclease cleavage of targeted mRNA and it interacts with the mRNA-binding protein GW182, which is a marker for cytoplasmic foci referred to as GW bodies (GWBs). We demonstrated that the anti-Ago2 monoclonal antibody 4F9 recognized GWBs in a cell cycle dependent manner and was capable of capturing miRNAs associated with Ago2. Since Ago2 protein is the effector protein of RNAi, anti-Ago2 monoclonal antibody may be useful in capturing functional miRNAs.

  9. Synthesis, Characterization, and Biological Evaluation of Anti-HER2 Indocyanine Green-Encapsulated PEG-Coated PLGA Nanoparticles for Targeted Phototherapy of Breast Cancer Cells.

    PubMed

    Lee, Yu-Hsiang; Lai, Yun-Han

    2016-01-01

    Human epidermal growth factor receptor 2 (HER2)-overexpressed breast cancer is known to be more aggressive and resistant to medicinal treatment and therefore to whom an alternative therapeutics is needed. Indocyanine green (ICG) has been widely exploited in breast cancer phototherapy. However, drawbacks of accelerated degradation and short half-life (2-4 min) in blood seriously hamper its use in the clinic. To overcome these challenges, an anti-HER2 ICG-encapsulated polyethylene glycol-coated poly(lactic-co-glycolic acid) nanoparticles (HIPPNPs) were developed in this study. Through the analyses of degradation rate coefficients of ICG with and without polymeric encapsulation, the photostability of HIPPNP-entrapped ICG significantly enhanced 4 folds (P < 0.05) while its thermal stabilities at 4 and 37°C significantly enhanced 5 and 3 (P < 0.05 for each) folds, respectively, under equal lighting and/or heating treatment for 48 h. The target specificity of HIPPNPs to HER2-positive cells was demonstrated based on a 6-fold (P < 0.05) enhancement of uptake efficiency of HIPPNPs in MDA-MB-453/HER2(+) cells within 4 h as compared with that in MCF7/HER2(-) cells. Moreover, the HIPPNPs with ≤ 25 μM ICG equivalent were nontoxic to cells in the absence of light illumination, and enabled to generate similar amount of singlet oxygen and hyperthermia effect as compared with that used by free ICG upon NIR irradiation. After 808 nm-laser irradiation with intensity of 6 W/cm2 for 5 min, the viability of MDA-MB-453 cells pre-treated by HIPPNPs with ≥ 5 μM ICG equivalent for 4 h significantly reduced as compared with that treated by equal concentration of free ICG (P < 0.05) and > 90% of the cells were eradicated while the dose of HIPPNPs was increased to 25 μM ICG equivalent. In summary, the developed HIPPNPs are anticipated as a feasible tool for use in phototherapy of breast cancer cells with HER2 expression.

  10. Imaging biomarkers to predict response to anti-HER2 (ErbB2) therapy in preclinical models of breast cancer

    PubMed Central

    Shah, Chirayu; Miller, Todd W.; Wyatt, Shelby K.; McKinley, Eliot T.; Olivares, Maria Graciela; Sanchez, Violeta; Nolting, Donald D.; Buck, Jason R.; Zhao, Ping; Ansari, M. Sib; Baldwin, Ronald M.; Gore, John C.; Schiff, Rachel; Arteaga, Carlos L.; Manning, H. Charles

    2010-01-01

    Purpose To evaluate non-invasive imaging methods as predictive biomarkers of response to trastuzumab in mouse models of HER2-overexpressing breast cancer. The correlation between tumor regression and molecular imaging of apoptosis, glucose metabolism, and cellular proliferation was evaluated longitudinally in responding and non-responding tumor-bearing cohorts. Experimental Design Mammary tumors from MMTV/HER2 transgenic female mice were transplanted into syngeneic female mice. BT474 human breast carcinoma cell line xenografts were grown in athymic nude mice. Tumor cell apoptosis (NIR700-Annexin-V accumulation), glucose metabolism ([18F]FDG-PET), and proliferation ([18F]FLT-PET) were evaluated throughout a bi-weekly trastuzumab regimen. Imaging metrics were validated by direct measurement of tumor size and immunohistochemical (IHC) analysis of cleaved caspase-3, phosphorylated AKT (p-AKT) and Ki67. Results NIR700-Annexin-V accumulated significantly in trastuzumab-treated MMTV/HER2 and BT474 tumors that ultimately regressed, but not in non-responding or vehicle-treated tumors. Uptake of [18F]FDG was not affected by trastuzumab treatment in MMTV/HER2 or BT474 tumors. [18F]FLT PET imaging predicted trastuzumab response in BT474 tumors but not in MMTV/HER2 tumors, which exhibited modest uptake of [18F]FLT. Close agreement was observed between imaging metrics and IHC analysis. Conclusions Molecular imaging of apoptosis accurately predicts trastuzumab-induced regression of HER2(+) tumors and may warrant clinical exploration to predict early response to neoadjuvant trastuzumab. Trastuzumab does not appear to alter glucose metabolism substantially enough to afford [18F]FDG-PET significant predictive value in this setting. Although promising in one preclinical model, further studies are required to determine the overall value of [18F]FLT-PET as a biomarker of response to trastuzumab in HER2+ breast cancer. PMID:19584166

  11. HER Story: The Next Chapter in HER-2-Directed Therapy for Advanced Breast Cancer

    PubMed Central

    Joy, Anil A.; Rayson, Daniel; McLeod, Deanna; Brezden-Masley, Christine; Boileau, Jean-François; Gelmon, Karen A.

    2013-01-01

    Untreated human epidermal growth factor receptor-2 (HER-2)-positive advanced breast cancer (ABC) is an aggressive disease, associated with a poor prognosis and short overall survival. HER-2-directed therapy prolongs both time to disease progression and overall survival when combined with chemotherapy and has become the standard of care for those with HER-2-positive breast cancer in the early and advanced settings. Despite the remarkable therapeutic impact HER-2-directed therapy has had on disease outcomes, some patients with HER-2-positive disease will have primary resistant disease and others will respond initially but will eventually have progression, underscoring the need for other novel therapeutic options. This article reviews recent phase III trial data and discusses a practical approach to sequencing of HER-2-directed therapy in patients with HER-2-positive ABC. The significant cumulative survival gains seen in these trials are slowly reshaping the landscape of HER-2-positive ABC outcomes. PMID:24212500

  12. Generation, characterization and in vivo biological activity of two distinct monoclonal anti-PEG IgMs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hashimoto, Yosuke; Shimizu, Taro; Mima, Yu

    PEGylation, the attachment of polyethylene glycol (PEG) to nanocarriers and proteins, is a widely accepted approach to improving the in vivo efficacy of the non-PEGylated products. However, both PEGylated liposomes and PEGylated proteins reportedly trigger the production of specific antibodies, mainly IgM, against the PEG moiety, which possibly leads to a reduction in safety and therapeutic efficacy of the PEGylated products. In the present study, two monoclonal anti-PEG IgMs — HIK-M09 via immunization with an intravenous injection of PEGylated liposomes (SLs) and HIK-M11 via immunization with a subcutaneous administration of PEGylated ovalbumin (PEG-OVA) were successfully generated. The generated IgMs showedmore » efficient reactivity to mPEG{sub 2000} conjugated to 1,2-distearoyl-sn-glycero-3-phospho-ethanolamine (DSPE), PEGylated liposome (SL) and PEG-OVA. It appears that HIK-M09 recognizes ethoxy (OCH{sub 2}CH{sub 2}) repeat units along with a terminal motif of PEG, while HIK-M11 recognizes only ethoxy repeat units of PEG. Such unique properties allow HIK-M09 to bind with dense PEG. In addition, their impact on the in vivo clearance of the PEGylated products was investigated. It was found that the generated ant-PEG IgMs induced a clearance of SL as they were intravenously administered with SL. Interestingly, the HIK-M11, generated by PEG-OVA, induced the clearance of both SL and PEG-OVA, while the HIK-M09, generated by SL, induced the clearance of SL only. We here revealed that the presence of serum anti-PEG IgM and the subsequent binding of anti-PEG IgM to the PEGylated products are not necessarily related to the enhanced clearance of the products. It appears that subsequent complement activation following anti-PEG IgM binding is the most important step in dictating the in vivo fate of PEGylated products. This study may have implications for the design, development and clinical application of PEGylated products and therapeutics. - Highlights: • Two

  13. Anti-Ebola therapies based on monoclonal antibodies: current state and challenges ahead.

    PubMed

    González-González, Everardo; Alvarez, Mario Moisés; Márquez-Ipiña, Alan Roberto; Trujillo-de Santiago, Grissel; Rodríguez-Martínez, Luis Mario; Annabi, Nasim; Khademhosseini, Ali

    2017-02-01

    The 2014 Ebola outbreak, the largest recorded, took us largely unprepared, with no available vaccine or specific treatment. In this context, the World Health Organization declared that the humanitarian use of experimental therapies against Ebola Virus (EBOV) is ethical. In particular, an experimental treatment consisting of a cocktail of three monoclonal antibodies (mAbs) produced in tobacco plants and specifically directed to the EBOV glycoprotein (GP) was tested in humans, apparently with good results. Several mAbs with high affinity to the GP have been described. This review discusses our current knowledge on this topic. Particular emphasis is devoted to those mAbs that have been assayed in animal models or humans as possible therapies against Ebola. Engineering aspects and challenges for the production of anti-Ebola mAbs are also briefly discussed; current platforms for the design and production of full-length mAbs are cumbersome and costly.

  14. Suppression of allo-human leucocyte antigen (HLA) antibodies secreted by B memory cells in vitro: intravenous immunoglobulin (IVIg) versus a monoclonal anti-HLA-E IgG that mimics HLA-I reactivities of IVIg.

    PubMed

    Zhu, D; Ravindranath, M H; Terasaki, P I; Miyazaki, T; Pham, T; Jucaud, V

    2014-08-01

    B memory cells remain in circulation and secrete alloantibodies without antigen exposure > 20 years after alloimmunization postpartum or by transplantation. These long-lived B cells are resistant to cytostatic drugs. Therapeutically, intravenous immunoglobulin (IVIg) is administered to reduce allo-human leucocyte antigen (HLA) antibodies pre- and post-transplantation, but the mechanism of reduction remains unclear. Recently, we reported that IVIg reacts with several HLA-I alleles and the HLA reactivity of IVIg is lost after its HLA-E reactivity is adsorbed out. Therefore, we have generated an anti-HLA-E monoclonal antibody that mimics the HLA-reactivity of IVIg to investigate whether this antibody suppresses IgG secretion, as does IVIg. B cells were purified from the blood of a woman in whose blood the B memory cells remained without antigen exposure > 20 years after postpartum alloimmunization. The B cells were stimulated with cytokines using a well-defined culture system. The anti-HLA-E monoclonal antibody (mAb) significantly suppressed the allo-HLA class-II IgG produced by the B cells, and that this suppression was far superior to that by IVIg. These findings were confirmed with HLA-I antibody secreted by the immortalized B cell line, developed from the blood of another alloimmunized woman. The binding affinity of the anti-HLA-E mAb for peptide sequences shared (i.e. shared epitopes) between HLA-E and other β2-microglobulin-free HLA heavy chains (open conformers) on the cell surface of B cells may act as a ligand and signal suppression of IgG production of activated B memory cells. We propose that anti-HLA-E monoclonal antibody may also be useful to suppress allo-HLA IgG production in vivo. © 2014 British Society for Immunology.

  15. Her-2-neu expression and progression toward androgen independence in human prostate cancer.

    PubMed

    Signoretti, S; Montironi, R; Manola, J; Altimari, A; Tam, C; Bubley, G; Balk, S; Thomas, G; Kaplan, I; Hlatky, L; Hahnfeldt, P; Kantoff, P; Loda, M

    2000-12-06

    Human prostate cancers are initially androgen dependent but ultimately become androgen independent. Overexpression of the Her-2-neu receptor tyrosine kinase has been associated with the progression to androgen independence in prostate cancer cells. We examined the expression of Her-2-neu in normal and cancerous prostate tissues to assess its role in the progression to androgen independence. Prostate cancer tissue sections were obtained from 67 patients treated by surgery alone (UNT tumors), 34 patients treated with total androgen ablation therapy before surgery (TAA tumors), and 18 patients in whom total androgen ablation therapy failed and who developed bone metastases (androgen-independent [AI] disease). The sections were immunostained for Her-2-neu, androgen receptor (AR), prostate-specific antigen (PSA), and Ki-67 (a marker of cell proliferation) protein expression. Messenger RNA (mRNA) levels and gene amplification of Her-2-neu were examined by RNA in situ hybridization and fluorescent in situ hybridization(FISH), respectively, in a subset of 27 tumors (nine UNT, 11 TAA, and seven AI). All statistical tests were two-sided. Her-2-neu protein expression was statistically significantly higher in TAA tumors than in UNT tumors with the use of two different scoring methods (P =.008 and P =.002). The proportion of Her-2-neu-positive tumors increased from the UNT group (17 of 67) to the TAA group (20 of 34) to the AI group (14 of 18) (P<.001). When compared with UNT tumors, tumor cell proliferation was higher in AI tumors (P =.014) and lower in TAA tumors (P<.001). All tumors expressed AR and PSA proteins. Although Her-2-neu mRNA expression was high in TAA and AI tumors, no Her-2-neu gene amplification was detected by FISH in any of the tumor types. Her-2-neu expression appears to increase with progression to androgen independence. Thus, therapeutic targeting of this tyrosine kinase in prostate cancer may be warranted.

  16. Analyses of the peripheral immunome following multiple administrations of avelumab, a human IgG1 anti-PD-L1 monoclonal antibody.

    PubMed

    Donahue, Renee N; Lepone, Lauren M; Grenga, Italia; Jochems, Caroline; Fantini, Massimo; Madan, Ravi A; Heery, Christopher R; Gulley, James L; Schlom, Jeffrey

    2017-01-01

    Multiple anti-PD-L1/PD-1 checkpoint monoclonal antibodies (MAb) have shown clear evidence of clinical benefit. All except one have been designed or engineered to omit the possibility to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) as a second potential mode of anti-tumor activity; the reason for this is the concern of lysis of PD-L1 positive immune cells. Avelumab is a fully human IgG1 MAb which has been shown in prior in vitro studies to mediate ADCC versus a range of human tumor cells, and clinical studies have demonstrated anti-tumor activity versus a range of human cancers. This study was designed to investigate the effect on immune cell subsets in the peripheral blood of cancer patients prior to and following multiple administrations of avelumab. One hundred twenty-three distinct immune cell subsets in the peripheral blood of cancer patients ( n  = 28) in a phase I trial were analyzed by flow cytometry prior to and following one, three, and nine cycles of avelumab. Changes in soluble (s) CD27 and sCD40L in plasma were also evaluated. In vitro studies were also performed to determine if avelumab would mediate ADCC of PBMC. No statistically significant changes in any of the 123 immune cell subsets analyzed were observed at any dose level, or number of doses, of avelumab. Increases in the ratio of sCD27:sCD40L were observed, suggesting potential immune activation. Controlled in vitro studies also showed lysis of tumor cells by avelumab versus no lysis of PBMC from five donors. These studies demonstrate the lack of any significant effect on multiple immune cell subsets, even those expressing PD-L1, following multiple cycles of avelumab. These results complement prior studies showing anti-tumor effects of avelumab and comparable levels of adverse events with avelumab versus other anti-PD-1/PD-L1 MAbs. These studies provide the rationale to further exploit the potential ADCC mechanism of action of avelumab as well as other human IgG1 checkpoint

  17. Generation of HER2-specific antibody immunity during trastuzumab adjuvant therapy associates with reduced relapse in resected HER2 breast cancer.

    PubMed

    Norton, Nadine; Fox, Nicholas; McCarl, Christie-Ann; Tenner, Kathleen S; Ballman, Karla; Erskine, Courtney L; Necela, Brian M; Northfelt, Donald; Tan, Winston W; Calfa, Carmen; Pegram, Mark; Colon-Otero, Gerardo; Perez, Edith A; Clynes, Raphael; Knutson, Keith L

    2018-06-14

    Resected HER2 breast cancer patients treated with adjuvant trastuzumab and chemotherapy have superior survival compared to patients treated with chemotherapy alone. We previously showed that trastuzumab and chemotherapy induce HER2-specific antibodies which correlate with improved survival in HER2 metastatic breast cancer patients. It remains unclear whether the generation of immunity required trastuzumab and whether endogenous antibody immunity is associated with improved disease-free survival in the adjuvant setting. In this study, we addressed this question by analyzing serum anti-HER2 antibodies from a subset of patients enrolled in the NCCTG trial N9831, which includes an arm (Arm A) in which trastuzumab was not used. Arms B and C received trastuzumab sequentially or concurrently to chemotherapy, respectively. Pre-and post-treatment initiation sera were obtained from 50 women enrolled in N9831. Lambda IgG antibodies (to avoid detection of trastuzumab) to HER2 were measured and compared between arms and with disease-free survival. Prior to therapy, across all three arms, N9831 patients had similar mean anti-HER2 IgG levels. Following treatment, the mean levels of antibodies increased in the trastuzumab arms but not the chemotherapy-only arm. The proportion of patients who demonstrated antibodies increased by 4% in Arm A and by 43% in the Arms B and C combined (p = 0.003). Cox modeling demonstrated that larger increases in antibodies were associated with improved disease-free survival in all patients (HR = 0.23; p = 0.04). These results show that the increased endogenous antibody immunity observed in adjuvant patients treated with combination trastuzumab and chemotherapy is clinically significant, in view of its correlation with improved disease-free survival. The findings may have important implications for predicting treatment outcomes in patients treated with trastuzumab in the adjuvant setting. ClinicalTrials.gov, NCT00005970 . Registered on July

  18. Single-cell quantitative HER2 measurement identifies heterogeneity and distinct subgroups within traditionally defined HER2-positive patients.

    PubMed

    Onsum, Matthew D; Geretti, Elena; Paragas, Violette; Kudla, Arthur J; Moulis, Sharon P; Luus, Lia; Wickham, Thomas J; McDonagh, Charlotte F; MacBeath, Gavin; Hendriks, Bart S

    2013-11-01

    Human epidermal growth factor receptor 2 (HER2) is an important biomarker for breast and gastric cancer prognosis and patient treatment decisions. HER2 positivity, as defined by IHC or fluorescent in situ hybridization testing, remains an imprecise predictor of patient response to HER2-targeted therapies. Challenges to correct HER2 assessment and patient stratification include intratumoral heterogeneity, lack of quantitative and/or objective assays, and differences between measuring HER2 amplification at the protein versus gene level. We developed a novel immunofluorescence method for quantitation of HER2 protein expression at the single-cell level on FFPE patient samples. Our assay uses automated image analysis to identify and classify tumor versus non-tumor cells, as well as quantitate the HER2 staining for each tumor cell. The HER2 staining level is converted to HER2 protein expression using a standard cell pellet array stained in parallel with the tissue sample. This approach allows assessment of HER2 expression and heterogeneity within a tissue section at the single-cell level. By using this assay, we identified distinct subgroups of HER2 heterogeneity within traditional definitions of HER2 positivity in both breast and gastric cancers. Quantitative assessment of intratumoral HER2 heterogeneity may offer an opportunity to improve the identification of patients likely to respond to HER2-targeted therapies. The broad applicability of the assay was demonstrated by measuring HER2 expression profiles on multiple tumor types, and on normal and diseased heart tissues. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  19. Expression of HER2/Neu in B-Cell Acute Lymphoblastic Leukemia.

    PubMed

    Rodriguez-Rodriguez, Sergio; Pomerantz, Alan; Demichelis-Gomez, Roberta; Barrera-Lumbreras, Georgina; Barrales-Benitez, Olga; Aguayo-Gonzalez, Alvaro

    2016-01-01

    The expression of HER2/neu in B-cell acute lymphoblastic leukemia has been reported in previous studies. The objective of this research was to study the expression of HER2/neu on the blasts of patients with acute leukemia from the Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran. From June 2015 to February 2016, a HER2/neu monoclonal antibody was added to the panel of antibodies that we routinely use in patients with acute leukemia. An expression of ≥ 30% was considered positive. We studied 33 patients: 19 had de novo leukemia (57.6%), three (9.1%) were in relapse, and in 11 (33.3%) their status could not be specified. Seventeen patients (51.5%) were classified as B-cell acute lymphoblastic leukemia with a median expression of HER2/neu of 0.3% (range 0-90.2). Three patients with B-cell acute lymphoblastic leukemia were positive for HER2/neu: 89.4%, 90.9%, and 62.4%. The first and third patient had de novo B-cell acute lymphoblastic leukemia. The second patient was in second relapse after allogeneic stem cell transplant. All three patients were categorized as high-risk at the time of diagnosis. In the studied Mexican population, we found a positive expression of HER2/neu in 17% of the B-cell acute lymphoblastic leukemia patients, similar to previous studies in which the expression was found in 15-50%.

  20. Induction of HER2 Immunity in Outbred Domestic Cats by DNA Electrovaccination

    PubMed Central

    Gibson, Heather; Veenstra, Jesse; Jones, Richard; Vaishampayan, Ulka; Sauerbrey, Michele; Bepler, Gerold; Lum, Lawrence; Reyes, Joyce; Weise, Amy; Wei, Wei-Zen

    2015-01-01

    Domestic cats share human living environments and genetic traits. They develop spontaneous feline mammary carcinoma (FMC) with histopathology similar to human breast cancer. HER2 and AKT phosphorylation was demonstrated in primary FMC by immunoblot, indicating HER2 as a therapeutic target. FMC lines K12 and K248 expressing HER1, HER2 and HER3 were sensitive to receptor tyrosine kinase (RTK) inhibitors gefitinib and lapatinib. To test HER2 vaccine response in cats, purpose-bred, healthy cats were electrovaccinated with heterologous (xenogeneic) or point-mutated feline HER2 DNA. T-cell reactivity to feline self-HER2 was detected in 4 of 10 cats that received bear HER2, human/rat fusion HER2 (E2Neu) or mutant feline HER2 (feHER2-K) which contains a single amino acid substitution. The variable T-cell responses may resemble that in the genetically heterogeneous human population. All immune sera to heterologous HER2 recognized feline HER2 expressed in 3T3 cells (3T3/HER2), but not that in FMC K12 or K248. Immune sera to mutant pfeHER2-K bound 3T3/HER2 cells weakly, but they demonstrated better recognition of K12 and K248 cells that also express HER1 and HER3, suggesting distinct HER2 epitopes displayed by FMC that may be simulated by feHER2-K. In summary, HER2 DNA electroporation overcomes T-cell immune tolerance in ~40% healthy cats and induces antibodies with distinct specificity. Vaccination studies in domestic cats can expedite vaccine iteration to guide human vaccine design and better predict outcome, with the added benefit of helping feline mammary tumor patients. PMID:25711535

  1. Therapeutic potential of an anti-high mobility group box-1 monoclonal antibody in epilepsy.

    PubMed

    Zhao, Junli; Wang, Yi; Xu, Cenglin; Liu, Keyue; Wang, Ying; Chen, Liying; Wu, Xiaohua; Gao, Feng; Guo, Yi; Zhu, Junming; Wang, Shuang; Nishibori, Masahiro; Chen, Zhong

    2017-08-01

    Brain inflammation is a major factor in epilepsy, and the high mobility group box-1 (HMGB1) protein is known to contribute significantly to the generation of seizures. Here, we investigated the therapeutic potential of an anti-HMGB1 monoclonal antibody (mAb) in epilepsy. anti-HMGB1 mAb attenuated both acute seizure models (maximal electroshock seizure, pentylenetetrazole-induced and kindling-induced), and chronic epilepsy model (kainic acid-induced) in a dose-dependent manner. Meanwhile, the anti-HMGB1 mAb also attenuated seizure activities of human brain slices obtained from surgical resection from drug-resistant epilepsy patients. The mAb showed an anti-seizure effect with a long-term manner and appeared to be minimal side effects at even very high dose (no disrupted physical EEG rhythm and no impaired basic physical functions, such as body growth rate and thermoregulation). This anti-seizure effect of mAb results from its inhibition of translocated HMGB1 from nuclei following seizures, and the anti-seizure effect was absent in toll-like receptor 4 knockout (TLR4 -/- ) mice. Interestingly, the anti-HMGB1 mAb also showed a disease-modifying anti-epileptogenetic effect on epileptogenesis after status epileptics, which is indicated by reducing seizure frequency and improving the impaired cognitive function. These results indicate that the anti-HMGB1 mAb should be viewed as a very promising approach for the development of novel therapies to treat refractory epilepsy. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Interplay between Natural Killer Cells and Anti-HER2 Antibodies: Perspectives for Breast Cancer Immunotherapy

    PubMed Central

    Muntasell, Aura; Cabo, Mariona; Servitja, Sonia; Tusquets, Ignasi; Martínez-García, María; Rovira, Ana; Rojo, Federico; Albanell, Joan; López-Botet, Miguel

    2017-01-01

    Overexpression of the human epidermal growth factor receptor 2 (HER2) defines a subgroup of breast tumors with aggressive behavior. The addition of HER2-targeted antibodies (i.e., trastuzumab, pertuzumab) to chemotherapy significantly improves relapse-free and overall survival in patients with early-stage and advanced disease. Nonetheless, considerable proportions of patients develop resistance to treatment, highlighting the need for additional and co-adjuvant therapeutic strategies. HER2-specific antibodies can trigger natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity and indirectly enhance the development of tumor-specific T cell immunity; both mechanisms contributing to their antitumor efficacy in preclinical models. Antibody-dependent NK cell activation results in the release of cytotoxic granules as well as the secretion of pro-inflammatory cytokines (i.e., IFNγ and TNFα) and chemokines. Hence, NK cell tumor suppressive functions include direct cytolytic killing of tumor cells as well as the regulation of subsequent antitumor adaptive immunity. Albeit tumors with gene expression signatures associated to the presence of cytotoxic lymphocyte infiltrates benefit from trastuzumab-based treatment, NK cell-related biomarkers of response/resistance to HER2-specific therapeutic antibodies in breast cancer patients remain elusive. Several variables, including (i) the configuration of the patient NK cell repertoire; (ii) tumor molecular features (i.e., estrogen receptor expression); (iii) concomitant therapeutic regimens (i.e., chemotherapeutic agents, tyrosine kinase inhibitors); and (iv) evasion mechanisms developed by progressive breast tumors, have been shown to quantitatively and qualitatively influence antibody-triggered NK cell responses. In this review, we discuss possible interventions for restoring/enhancing the therapeutic activity of HER2 therapeutic antibodies by harnessing NK cell antitumor potential through combinatorial

  3. HER-3 peptide vaccines/mimics: Combined therapy with IGF-1R, HER-2, and HER-1 peptides induces synergistic antitumor effects against breast and pancreatic cancer cells.

    PubMed

    Miller, Megan Jo; Foy, Kevin C; Overholser, Jay P; Nahta, Rita; Kaumaya, Pravin Tp

    2014-11-01

    The human epidermal growth factor receptor 3 (HER-3/ErbB3) is a unique member of the human epidermal growth factor family of receptors, because it lacks intrinsic kinase activity and ability to heterodimerize with other members. HER-3 is frequently upregulated in cancers with epidermal growth factor receptor (EGFR/HER-1/ErbB1) or human epidermal growth factor receptor 2 (HER-2/ErBB2) overexpression, and targeting HER-3 may provide a route for overcoming resistance to agents that target EGFR or HER-2. We have previously developed vaccines and peptide mimics for HER-1, HER-2 and vascular endothelial growth factor (VEGF). In this study, we extend our studies by identifying and evaluating novel HER-3 peptide epitopes encompassing residues 99-122, 140-162, 237-269 and 461-479 of the HER-3 extracellular domain as putative B-cell epitopes for active immunotherapy against HER-3 positive cancers. We show that the HER-3 vaccine antibodies and HER-3 peptide mimics induced antitumor responses: inhibition of cancer cell proliferation, inhibition of receptor phosphorylation, induction of apoptosis and antibody dependent cellular cytotoxicity (ADCC). Two of the HER-3 epitopes 237-269 (domain II) and 461-479 (domain III) significantly inhibited growth of xenografts originating from both pancreatic (BxPC3) and breast (JIMT-1) cancers. Combined therapy of HER-3 (461-471) epitope with HER-2 (266-296), HER-2 (597-626), HER-1 (418-435) and insulin-like growth factor receptor type I (IGF-1R) (56-81) vaccine antibodies and peptide mimics show enhanced antitumor effects in breast and pancreatic cancer cells. This study establishes the hypothesis that combination immunotherapy targeting different signal transduction pathways can provide effective antitumor immunity and long-term control of HER-1 and HER-2 overexpressing cancers.

  4. Internalization and Recycling of the HER2 Receptor on Human Breast Adenocarcinoma Cells Treated with Targeted Phototoxic Protein DARPinminiSOG

    PubMed Central

    Shilova, O. N.; Proshkina, G. M.; Lebedenko, E. N.; Deyev, S. M.

    2015-01-01

    Design and evaluation of new high-affinity protein compounds that can selectively and efficiently destroy human cancer cells are a priority research area in biomedicine. In this study we report on the ability of the recombinant phototoxic protein DARPin-miniSOG to interact with breast adenacarcinoma human cells overexpressing the extracellular domain of human epidermal growth factor receptor 2 (HER2). It was found that the targeted phototoxin DARPin-miniSOG specifically binds to the HER2 with following internalization and slow recycling back to the cell membrane. An insight into the role of DARPin-miniSOG in HER2 internalization could contribute to the treatment of HER2-positive cancer using this phototoxic protein. PMID:26483969

  5. Anti-Ebola therapies based on monoclonal antibodies: Current state and challenges ahead

    PubMed Central

    González-González, E; Alvarez, MM; Márquez-Ipiña, AR; Santiago, G Trujillo-de; Rodríguez-Martínez, LM; Annabi, N; Khademhosseini, A

    2017-01-01

    The 2014 Ebola outbreak, the largest recorded, took us largely unprepared, with no available vaccine or specific treatment. In this context, the World Health Organization (WHO) declared that the humanitarian use of experimental therapies against Ebola Virus (EBOV) is ethical. In particular, an experimental treatment consisting of a cocktail of three monoclonal antibodies (mAbs) produced in tobacco plants and specifically directed to the Ebola virus glycoprotein (GP) was tested in humans, apparently with good results. Several mAbs with high affinity to the GP have been described. This review discusses our current knowledge on this topic. Particular emphasis is devoted to those mAbs that have been assayed in animal models or humans as possible therapies against Ebola. Engineering aspects and challenges for the production of anti-Ebola mAbs are also briefly discussed; current platforms for the design and production of full-length mAbs are cumbersome and costly. PMID:26611830

  6. Monoclonal antibody binding to the macrophage-specific receptor sialoadhesin alters the phagocytic properties of human and mouse macrophages.

    PubMed

    De Schryver, Marjorie; Cappoen, Davie; Elewaut, Dirk; Nauwynck, Hans J; Maes, Louis; Caljon, Guy; Cos, Paul; Delputte, Peter L

    2017-02-01

    Sialoadhesin (Sn) is a surface receptor expressed on macrophages in steady state conditions, but during inflammation, Sn can be upregulated both on macrophages and on circulating monocytes. It was shown for different species that Sn becomes internalized after binding with monoclonal antibodies. These features suggest that Sn is a potential target for immunotherapies. In this study, human and mouse macrophages were treated with anti-Sn monoclonal antibodies or F(ab') 2 fragments and the effect of their binding to Sn on phagocytosis was analyzed. Binding of antibodies to Sn resulted in delayed and reduced phagocytosis of fluorescent beads. No effect was observed on Fc-mediated phagocytosis or phagocytosis of bacteria by human macrophages. In contrast, an enhanced phagocytosis of bacteria by mouse macrophages was detected. These results showed that stimulation of Sn could have different effects on macrophage phagocytosis, depending both on the type of phagocytosis and cellular background. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. A SPR strategy for high-throughput ligand screenings based on synthetic peptides mimicking a selected subdomain of the target protein: a proof of concept on HER2 receptor.

    PubMed

    Monfregola, Luca; Vitale, Rosa Maria; Amodeo, Pietro; De Luca, Stefania

    2009-10-01

    The discovery of pharmaceutical agents is a complex, lengthy and costly process, critically depending on the availability of rapid and efficient screening methods. In particular, when targets are large, multidomain proteins, their complexity may affect unfavorably technical feasibility, costs and unambiguity of binding test interpretation. A possible strategy to overcome these problems relies on molecular design of receptor fragments that are: sensible targets for ligand screenings, conformationally stable also as standalone domains, easily synthesized and immobilized on chip for Biacore experiments. An additional desirable feature for new ligands is the ability of selectively targeting alternative conformational states typical of many proteins. To test the feasibility of such approach on a case with potential applicative interest, we developed a surface plasmon resonance (SPR)-based screening method for drug candidates toward HER2, a Tyr-kinase receptor targeted in anticancer therapies. HER2 was mimicked by HER2-DIVMP, a modified fragment of it immobilized onto the sensor surface specifically modeling HER2 domain IV in its bounded form, designed by structural comparison of HER2 alone and in complex with Herceptin, a monoclonal therapeutic anti-HER2 antibody. This design and its implementation in SPR devices was validated by investigating Herceptin- HER2-DIVMP affinity, measuring its dissociation constant (K(D)=19.2 nM). An efficient synthetic procedure to prepare the HER2-DIVMP peptide was also developed. The HER2-DIVMP conformational stability suggested by experimental and computational results, makes it also a valuable candidate as a mold to design new molecules selectively targeting domain IV of HER2.

  8. Long-term remission of a Her2/neu positive primary breast cancer under double monoclonal antibody therapy with trastuzumab and bevacizumab

    PubMed Central

    Königsberg, Robert; Maierhofer, Julia; Steininger, Tanja; Kienzer, Gabriele; Dittrich, Christian

    2014-01-01

    Background The attempt to act on several signalling pathways involved in tumour development simultaneously appears to be more attractive than attacking a single target structure alone. Vascular endothelial growth factor (VEGF) over-expression is frequently observed in human epidermal growth factor receptor 2 (Her2/neu) positive patients with breast cancer and over-expression of the proto-oncogene Her2/neu is associated with an up-regulation of VEGF. Case report The case of a Her2/neu positive patient with breast cancer who refused cytotoxic chemotherapy with its potential side effects as well as mastectomy is presented. Our patient has been receiving the combined double administration of bevacizumab and trastuzumab for more than 4 years. Conclusions This case report shows that (a) the combined double administration of bevacizumab and trastuzumab was be clinically effective. (b) The combination of bevacizumab and trastuzumab is safe and non-toxic. (c) Bevacizumab and trastuzumab can be used as a long-term application. PMID:24991208

  9. Sensitivity of HER-2/neu antibodies in archival tissue samples: potential source of error in immunohistochemical studies of oncogene expression.

    PubMed

    Press, M F; Hung, G; Godolphin, W; Slamon, D J

    1994-05-15

    HER-2/neu oncogene amplification and overexpression of breast cancer tissue has been correlated with poor prognosis in women with both node-positive and node-negative disease. However, several studies have not confirmed this association. Review of these studies reveals the presence of considerable methodological variability including differences in study size, follow-up time, techniques and reagents. The majority of papers with clinical follow-up information are immunohistochemical studies using archival, paraffin-embedded breast cancers, and a variety of HER-2/neu antibodies have been used in these studies. Very little information, however, is available about the ability of the antibodies to detect overexpression following tissue processing for paraffin-embedding. Therefore, a series of antibodies, reported in the literature or commercially available, were evaluated to assess their sensitivity and specificity as immunohistochemical reagents. Paraffin-embedded samples of 187 breast cancers, previously characterized as frozen specimens for HER-2/neu amplification by Southern blot and for overexpression by Northern blot, Western blot, and immunohistochemistry, were used. Two multitumor paraffin-embedded tissue blocks were prepared from the previously analyzed breast cancers as a panel of cases to test a series of previously studied and/or commercially available anti-HER-2/neu antibodies. Immunohistochemical staining results obtained with 7 polyclonal and 21 monoclonal antibodies in sections from paraffin-embedded blocks of these breast cancers were compared. The ability of these antibodies to detect overexpression was extremely variable, providing an important explantation for the variable overexpression rate reported in the literature.

  10. Pathobiological implications of the d16HER2 splice variant for stemness and aggressiveness of HER2-positive breast cancer

    PubMed Central

    Castagnoli, L; Ghedini, G C; Koschorke, A; Triulzi, T; Dugo, M; Gasparini, P; Casalini, P; Palladini, A; Iezzi, M; Lamolinara, A; Lollini, P L; Nanni, P; Chiodoni, C; Tagliabue, E; Pupa, S M

    2017-01-01

    We have previously shown that the d16HER2 splice variant is linked to HER2-positive breast cancer (BC) tumorigenesis, progression and response to Trastuzumab. However, the mechanisms by which d16HER2 contributes to HER2-driven aggressiveness and targeted therapy susceptibility remain uncertain. Here, we report that the d16HER2-positive mammary tumor cell lines MI6 and MI7, derived from spontaneous lesions of d16HER2 transgenic (tg) mice and resembling the aggressive features of primary lesions, are enriched in the expression of Wnt, Notch and epithelial–mesenchymal transition pathways related genes compared with full-length wild-type (WT) HER2-positive cells (WTHER2_1 and WTHER2_2) derived from spontaneous tumors arising in WTHER2 tg mice. MI6 cells exhibited increased resistance to anoikis and significantly higher mammosphere-forming efficiency (MFE) and self-renewal capability than the WTHER2-positive counterpart. Furthermore, d16HER2-positive tumor cells expressed a higher fraction of CD29High/CD24+/SCA1Low cells and displayed greater in vivo tumor engraftment in serial dilution conditions than WTHER2_1 cells. Accordingly, NOTCH inhibitors impaired mammosphere formation only in MI6 cells. A comparative analysis of stemness-related features driven by d16HER2 and WTHER2 in ad hoc engineered human BC cells (MCF7 and T47D) revealed a higher MFE and aldehyde dehydrogenase-positive staining in d16HER2- vs WTHER2-infected cells, sustaining consistent BC-initiating cell enrichment in the human setting. Moreover, marked CD44 expression was found in MCF7_d16 and T47D_d16 cells vs their WTHER2 and Mock counterparts. Clinically, BC cases from two distinct HER2-positive cohorts characterized by high levels of expression of the activated-d16HER2 metagene were significantly enriched in the Notch family and signal transducer genes vs those with low levels of the metagene. PMID:27641338

  11. Viral transduction of the HER2-extracellular domain expands trastuzumab-based photoimmunotherapy for HER2-negative breast cancer cells.

    PubMed

    Shimoyama, Kyoko; Kagawa, Shunsuke; Ishida, Michihiro; Watanabe, Shinichiro; Noma, Kazuhiro; Takehara, Kiyoto; Tazawa, Hiroshi; Hashimoto, Yuuri; Tanabe, Shunsuke; Matsuoka, Junji; Kobayashi, Hisataka; Fujiwara, Toshiyoshi

    2015-02-01

    The prognosis of HER2-positive breast cancer has been improved by trastuzumab therapy, which features high specificity and limited side effects. However, trastuzumab-based therapy has shortcomings. Firstly, HER2-targeted therapy is only applicable to HER2-expressing tumors, which comprise only 20-25% of primary breast cancers. Secondly, many patients who initially respond to trastuzumab ultimately develop disease progression. To overcome these problems, we employed virus-mediated HER2 transduction and photoimmunotherapy (PIT) which involves trastuzumab conjugated with a photosensitizer, trastuzumab-IR700, and irradiation of near-infrared light. We hypothesized that the gene transduction technique together with PIT would expand the range of tumor entities suitable for trastuzumab-based therapy and improve its antitumor activity. The HER2-extracellular domain (ECD) was transduced by the adenoviral vector, Ad-HER2-ECD, and PIT with trastuzumab-IR700 was applied in the HER2-negative cancer cells. Ad-HER2-ECD can efficiently transduce HER2-ECD into HER2-negative human cancer cells. PIT with trastuzumab-IR700 induced direct cell membrane destruction of Ad-HER2-ECD-transduced HER2-negative cancer cells. Novel combination of viral transduction of a target antigen and an antibody-based PIT would expand and potentiate molecular-targeted therapy even for target-negative or attenuated cancer cells.

  12. Correlation of monoclonal and polyclonal somatostatin receptor 5 antibodies in pancreatic neuroendocrine tumors

    PubMed Central

    Kaemmerer, Daniel; Lupp, Amelie; Peter, Luisa; Fischer, Elke; Schulz, Stefan; Klöppel, Günter; Hommann, Merten

    2013-01-01

    Aims: To evaluate the frequency of somatostatin-receptor 5 (SSTR 5) in pancreatic neuroendocrine tumors by using monoclonal and polyclonal antibodies. Material and Method: we analyzed 66 proven pancreatic neuroendocrine tumors immunohistochemically with monoclonal (clone UMB-4) and polyclonal SSTR 5-antibodies. Immunoreactive score (IRS) and DAKO-score Her2/neu were evaluated. Results: Immunohistochemistry analysis demonstrated for the IRS a significant higher staining of all specimen using the monoclonal antibodies ( IRS SSTR5 poly vs IRS SSTR 5 mono; 20.0% vs 30.3% p < 0.001) by a correlation of 0.21; p = 0.04. For the HER2 score there was also a significant higher staining in the monoclonal group (Her2 SSTR 5 poly vs Her2 SSTR 5 mono; 21.5% vs 28.8% p < 0.001) by a correlation of 0.20; p = 0.08. Conclusion: Both antibodies are useful in staining of SSTR, although UMB-4 demonstrated a 10% higher SSTR 5 staining. Due to the previous underestimated expression rate of SSTR 5, current standards in diagnostics and therapy should be reconsidered. The increasing usage of long-acting pansomatostatin receptor analogues will rise the adverse effects connected to SSTR5 binding. PMID:23236542

  13. Growth inhibition of tumor cells in vitro by using monoclonal antibodies against gonadotropin-releasing hormone receptor.

    PubMed

    Lee, Gregory; Ge, Bixia

    2010-07-01

    As the continuation of a previous study, synthetic peptides corresponding to the extracellular domains of human gonadotropin-releasing hormone (GnRH) receptor were used to generate additional monoclonal antibodies which were further characterized biochemically and immunologically. Among those identified to recognize GnRH receptor, monoclonal antibodies designated as GHR-103, GHR-106 and GHR-114 were found to exhibit high affinity (Kd < or = 1 x 10(-8) M) and specificity to GnRH receptor as judged by the whole cell binding immunoassay and Western blot assay. Both anti-GnRH receptor monoclonal antibodies and GnRH were shown to compete for the same binding site of GnRH receptor on the surface of cultured cancer cells. Growth inhibitions of cancer cells cultured in vitro were demonstrated by cellular apoptosis experiments (TUNEL and MTT assays) under different conditions of treatment with GHR-106 monoclonal antibody or GnRH analogs. It was generally observed that both GnRH I and GHR-106 effectively induce the apoptosis of cultured cancer cells as determined by TUNEL and MTT assays. Consistently, suppressions of gene expressions at mRNA levels were demonstrated with several ribosomal proteins (P0, P1, P2 and L37), when cancer cells were incubated with GnRH or GHR-106. The widespread expressions of GnRH receptor in almost all of the studied human cancer cell lines were also demonstrated by RT-PCR and Western blot assay, as well as indirect immunofluorescence assay with either of these monoclonal antibodies as the primary antibody. In view of the longer half life of antibodies as compared to that of GnRH or its analogs, anti-GnRH receptor monoclonal antibodies in humanized forms could function as GnRH analogs and serve as an ideal candidate of anti-cancer drugs for therapeutic treatments of various cancers in humans as well as for fertility regulations.

  14. In vivo targeting of HER2-positive tumor using 2-helix affibody molecules.

    PubMed

    Ren, Gang; Webster, Jack M; Liu, Zhe; Zhang, Rong; Miao, Zheng; Liu, Hongguang; Gambhir, Sanjiv S; Syud, Faisal A; Cheng, Zhen

    2012-07-01

    Molecular imaging of human epidermal growth factor receptor type 2 (HER2) expression has drawn significant attention because of the unique role of the HER2 gene in diagnosis, therapy and prognosis of human breast cancer. In our previous research, a novel cyclic 2-helix small protein, MUT-DS, was discovered as an anti-HER2 Affibody analog with high affinity through rational protein design and engineering. MUT-DS was then evaluated for positron emission tomography (PET) of HER2-positive tumor by labeling with two radionuclides, 68Ga and 18F, with relatively short half-life (t1/2<2 h). In order to fully study the in vivo behavior of 2-helix small protein and demonstrate that it could be a robust platform for labeling with a variety of radionuclides for different applications, in this study, MUT-DS was further radiolabeled with 64Cu or 111In and evaluated for in vivo targeting of HER2-positive tumor in mice. Design 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) conjugated MUT-DS (DOTA-MUT-DS) was chemically synthesized using solid phase peptide synthesizer and I2 oxidation. DOTA-MUT-DS was then radiolabeled with 64Cu or 111In to prepare the HER2 imaging probe (64Cu/111In-DOTA-MUT-DS). Both biodistribution and microPET imaging of the probe were evaluated in nude mice bearing subcutaneous HER2-positive SKOV3 tumors. DOTA-MUT-DS could be successfully synthesized and radiolabeled with 64Cu or 111In. Biodistribution study showed that tumor uptake value of 64Cu or 111In-labeled DOTA-MUT-DS was 4.66±0.38 or 2.17±0.15%ID/g, respectively, in nude mice bearing SKOV3 xenografts (n=3) at 1 h post-injection (p.i.). Tumor-to-blood and tumor-to-muscle ratios for 64Cu-DOTA-MUT-DS were attained to be 3.05 and 3.48 at 1 h p.i., respectively, while for 111In-DOTA-MUT-DS, they were 2.04 and 3.19, respectively. Co-injection of the cold Affibody molecule ZHER2:342 with 64Cu-DOTA-MUT-DS specifically reduced the SKOV3 tumor uptake of the probe by 48%. 111In

  15. Rat brain xenografts reverse hypogonadism in mice immunosuppressed with anti-CD4 monoclonal antibody.

    PubMed

    Honey, C R; Charlton, H M; Wood, K J

    1991-01-01

    This study examines the effect of immunosuppression with monoclonal antibodies (MAb) against the murine CD4 (L3T4), a cell surface glycoprotein expressed primarily on helper T-lymphocytes, on the viability and function of rat neural xenografts placed in the third ventricle of hypogonadal (hpg) mice. The hpg mouse fails to synthesize hypothalamic gonadotrophin releasing hormone (GnRH) and consequently there is a drastic reduction in pituitary gonadotrophic hormone content and a failure of postnatal gonadal development (Cattanach et al. 1977). Three groups of male hpg mice received xenografts of day 1 post natal rat preoptic area (POA) tissue, a source of GnRH neurons, to their third ventricle. Those immunosuppressed with anti-CD4 MAb all showed surviving graft tissue thirty days post-transplant and half of this group had enlarged testes with all stages of spermatogenesis. In those hpg mice which were injected with saline alone, or with an anti-CD8 (Lyt-2) antibody there was no xenograft survival. These results suggest that the injection of monoclonal antibodies against the T-helper subset may provide an alternative means of immunosuppression aimed at the enhancement of survival of tissue grafts in the CNS.

  16. Brain metastasis in gastroesophageal adenocarcinoma and HER2 status.

    PubMed

    Limon, Dror; Gal, Omer; Gordon, Noa; Katz, Lior; Perl, Gali; Purim, Ofer; Amit, Limor; Stemmer, Salomon M; Kundel, Yulia; Ben-Aharon, Irit; Brenner, Baruch; Siegal, Tali; Yust-Katz, Shlomit

    2018-06-01

    The increased survival of patients with gastroesophageal adenocarcinoma (GAD) following improvements in treatment has been accompanied by a rising incidence of secondary brain metastasis. HER2 amplification/overexpression, which has been associated with an increased risk of brain metastasis in breast cancer, is found in about 20% of patients with GAD. The aim of this study was to evaluate the effect of HER2 status on brain metastasis in GAD. The database of a tertiary cancer center was searched for patients with GAD diagnosed in 2011-2015, and data were collected on clinical characteristics, brain metastasis, HER2 status, and outcome. We identified 404 patients with a confirmed diagnosis of GAD. HER2 results were available for 298: 69 (23.2%) positive and 227 negative. Brain metastasis developed in 15 patients with GAD (3.7%); HER2 results, available in 13, were positive in 6, negative in 6, and equivocal in 1. The brain metastasis rate was significantly higher in HER2-positive than HER2-negative patients with GAD (6/69, 8.7% vs. 6/227, 2.6%; RR = 3.3, 95% CI 1.1-9.9, p = 0.034). Median overall survival from diagnosis of brain metastasis was 2.3 months, with no significant difference by HER2 status. HER2 positive GAD patients may be at increased risk to develop BM. Clinicians should maintain a lower threshold for performing brain imaging in patients with HER2-positive GAD given their increased risk of brain metastasis. The role of anti-HER2 agents in the development and treatment of brain metastasis in GAD warrants further study.

  17. Potency of a human monoclonal antibody to diphtheria toxin relative to equine diphtheria anti-toxin in a guinea pig intoxication model.

    PubMed

    Smith, Heidi L; Cheslock, Peter; Leney, Mark; Barton, Bruce; Molrine, Deborah C

    2016-08-17

    Prompt administration of anti-toxin reduces mortality following Corynebacterium diphtheriae infection. Current treatment relies upon equine diphtheria anti-toxin (DAT), with a 10% risk of serum sickness and rarely anaphylaxis. The global DAT supply is extremely limited; most manufacturers have ceased production. S315 is a neutralizing human IgG1 monoclonal antibody to diphtheria toxin that may provide a safe and effective alternative to equine DAT and address critical supply issues. To guide dose selection for IND-enabling pharmacology and toxicology studies, we dose-ranged S315 and DAT in a guinea pig model of diphtheria intoxication based on the NIH Minimum Requirements potency assay. Animals received a single injection of antibody premixed with toxin, were monitored for 30 days, and assigned a numeric score for clinical signs of disease. Animals receiving ≥ 27.5 µg of S315 or ≥ 1.75 IU of DAT survived whereas animals receiving ≤ 22.5 µg of S315 or ≤ 1.25 IU of DAT died, yielding a potency estimate of 17 µg S315/IU DAT (95% CI 16-21) for an endpoint of survival. Because some surviving animals exhibited transient limb weakness, likely a systemic sign of toxicity, DAT and S315 doses required to prevent hind limb paralysis were also determined, yielding a relative potency of 48 µg/IU (95% CI 38-59) for this alternate endpoint. To support advancement of S315 into clinical trials, potency estimates will be used to evaluate the efficacy of S315 versus DAT in an animal model with antibody administration after toxin exposure, more closely modeling anti-toxin therapy in humans.

  18. Development and characterization of a monoclonal antibody to human embryonal carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khazaeli, M.B.; Beierwaltes, W.H.; Pitt, G.S.

    1987-06-01

    A monoclonal anti-testicular carcinoma antibody was obtained via the somatic cell fusion technique by immunization of BALB/c mice with freshly prepared single cell suspension from a patient with testicular embryonal carcinoma with choriocarcinoma components. The hybridoma supernates were screened against the testicular carcinoma cells used in the immunization as well as normal mononuclear white blood cells isolated from the same patient. An antibody (5F9) was selected which bound to fresh tumor cells from two patients with embryonal testicular carcinoma and failed to bind to fresh tumor cells from 24 patients (2 seminoma, 2 melanoma, 3 neck, 2 esophageal, 1 ovarian,more » 3 colon, 1 prostate, 2 breast, 1 liposarcoma, 3 endometrial, 1 kidney, 1 adrenal, 1 larynx and 1 bladder tumors) or cell suspensions prepared from normal liver, lung, spleen, ovary, testes, kidney, red blood cells or white blood cells. The antibody was tested for its binding to several well established cancer cell lines, and was found to bind to the BeWo human choriocarcinoma and two human embryonal carcinoma cell lines. The antibody did not react with 22 other cell lines or with hCG. The antibody was labeled with /sup 131/I and injected into nude mice bearing BeWo tumors and evaluated for tumor localization by performing whole body scans with a gamma camera 5 days later. Six mice injected with the antibody showed positive tumor localization without the need for background subtraction while six mice injected with MOPC-21, a murine myeloma immunoglobulin, demonstrated much less tumor localization. Tissue distribution studies performed after scanning showed specific tumor localization (8:1 tumor: muscle) for the monoclonal antibody and no specific localization for MOPC-21.« less

  19. Alteration of Electrostatic Surface Potential Enhances Affinity and Tumor Killing Properties of Anti-ganglioside GD2 Monoclonal Antibody hu3F8.

    PubMed

    Zhao, Qi; Ahmed, Mahiuddin; Guo, Hong-fen; Cheung, Irene Y; Cheung, Nai-Kong V

    2015-05-22

    Ganglioside GD2 is highly expressed on neuroectodermal tumors and an attractive therapeutic target for antibodies that have already shown some clinical efficacy. To further improve the current antibodies, which have modest affinity, we sought to improve affinity by using a combined method of random mutagenesis and in silico assisted design to affinity-mature the anti-GD2 monoclonal antibody hu3F8. Using yeast display, mutants in the Fv with enhanced binding over the parental clone were FACS-sorted and cloned. In silico modeling identified the minimal key interacting residues involved in the important charged interactions with the sialic acid groups of GD2. Two mutations, D32H (L-CDR1) and E1K (L-FR1) altered the electrostatic surface potential of the antigen binding site, allowing for an increase in positive charge to enhance the interaction with the negatively charged GD2-pentasaccharide headgroup. Purified scFv and IgG mutant forms were then tested for antigen specificity by ELISA, for tissue specificity by immunohistochemistry, for affinity by BIACORE, for antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-mediated cytotoxicity in vitro, and for anti-tumor efficacy in xenografted humanized mice. The nearly 7-fold improvement in affinity of hu3F8 with a single D32H (L-CDR1) mutation translated into a ∼12-fold improvement in NK92MI-transfected CD16-mediated ADCC, a 6-fold improvement in CD32-mediated ADCC, and a 2.5-fold improvement in complement-mediated cytotoxicity while maintaining restricted normal tissue cross-reactivity and achieving substantial improvement in tumor ablation in vivo. Despite increasing GD2 affinity, the double mutation D32H (L-CDR1) and E1K (L-FR1) did not further improve anti-tumor efficacy. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Divisional role of quantitative HER2 testing in breast cancer.

    PubMed

    Yamamoto-Ibusuki, Mutsuko; Yamamoto, Yutaka; Fu, Peifen; Yamamoto, Satoko; Fujiwara, Saori; Honda, Yumi; Iyama, Ken-ichi; Iwase, Hirotaka

    2015-03-01

    Human epidermal growth factor receptor 2 (HER2) is amplified in human breast cancers in which therapy targeted to HER2 significantly improves patient outcome. We re-visited the use of real-time quantitative polymerase chain reaction (qPCR)-based assays using formalin-fixed paraffin-embedded (FFPE) tissues as alternative methods and investigated their particular clinical relevance. DNA and RNA were isolated from FFPE specimens and HER2 status was assessed by qPCR in 249 consecutive patients with primary breast cancer. Concordance with results forg immunohistochemistry (IHC) and in situ hybridization (ISH), clinical characteristics and survival was assessed. HER2 gene copy number had a stronger correlation with clinicopathological characteristics and excellent concordance with IHC/ISH results (Sensitivity: 96.7 %; concordance: 99.2 %). HER2 gene expression showed inadequate sensitivity, rendering it unsuitable to determine HER2 status (Sensitivity: 46.7 %; concordance: 92.1 %), but lower HER2 gene expression, leading to the classification of many cases as "false negative", contributed to a prediction of better prognosis within the HER2-amplified subpopulation. Quantitative HER2 assessments are suggested to have evolved their accuracy in this decade, which can be a potential alternative for HER2 diagnosis in line with the in situ method, while HER2 gene expression levels could provide additional information regarding prognosis or therapeutic strategy within a HER2-amplified subpopulation.

  1. Probing HER2-PUMA and EGFR-PUMA Crosstalks in Aggressive Breast Cancer

    DTIC Science & Technology

    2013-09-01

    malignant biology and drug-resistant phenotype of EGFR- and/or HER2-overexpressing breast cancer and to use the acquired knowledge for the development...with PUMA, we first assessed whether HER2 can physically interact with PUMA using immunoprecipitation/western blotting (IP/WB). We used SK-BR3 and BT...activate HER2. We subjected the cell lysates to IP/WB using a PUMA antibody for IP and immunoblotted with anti-phospho-tyrosine antibodies. As shown

  2. Clinical and pathological characterization of HER2 mutations in human breast cancer: a systematic review of the literature.

    PubMed

    Petrelli, Fausto; Tomasello, Gianluca; Barni, Sandro; Lonati, Veronica; Passalacqua, Rodolfo; Ghidini, Michele

    2017-11-01

    HER2 gene is a member of the epidermal growth factor receptor (EGFR) family. Across different malignancies, aberrations of HER2 gene commonly correspond to gain-of-function alterations leading to increased receptor signaling. We have reviewed the literature currently available on HER2 mutations in human breast cancer (BC) evaluating type and frequency of such mutations. The primary objective was to determine the frequency and the number of patients with HER2-mut in the series analyzed. The secondary objectives were to assess characteristics of mutated cases (ER and HER2 status and stage of disease, type of mutations, and finally the clinical outcome if reported). We retrieved 31 published papers, and the pooled rate of HER2 mutations across 12,905 BC patients was calculated. Overall, the frequency of HER2 mutations was 2.7% with most involving the intracellular domain. About 4% of patients were finally mutated. The predictive role was not described. Only 30% of these patients were simultaneously HER2 positive and 63% were ER positive. We have found that the prevalence of HER2 mutations is about 3%. These genic alterations are independently associated with HER2 amplification status, occurring in both ER-positive/HER2-negative diseases or HER2-enriched cancers. Ongoing trials are investigating small molecules tyrosine kinase inhibitors in patients harboring these mutations.

  3. Membrane Estrogen and HER-2 Receptors in Human Breast Cancer

    DTIC Science & Technology

    2002-07-01

    activation of G-proteins, adenylate cyclase, inositol phosphate, calcium homeostasis and/or MAP kinase. These interactions may promote phosphorylation of ER...of breast cancer cells and interact with transmembrane HER-2 growth factor receptors. Expression of HER-2 receptors occurs in many breast cancers...reports of significant cross-talk and interaction between erb B (HER) pathways and estrogen receptor signaling (3,24,27,34-36). It is generally held

  4. Activating HER2 mutations in HER2 gene amplification negative breast cancer.

    PubMed

    Bose, Ron; Kavuri, Shyam M; Searleman, Adam C; Shen, Wei; Shen, Dong; Koboldt, Daniel C; Monsey, John; Goel, Nicholas; Aronson, Adam B; Li, Shunqiang; Ma, Cynthia X; Ding, Li; Mardis, Elaine R; Ellis, Matthew J

    2013-02-01

    Data from 8 breast cancer genome-sequencing projects identified 25 patients with HER2 somatic mutations in cancers lacking HER2 gene amplification. To determine the phenotype of these mutations, we functionally characterized 13 HER2 mutations using in vitro kinase assays, protein structure analysis, cell culture, and xenograft experiments. Seven of these mutations are activating mutations, including G309A, D769H, D769Y, V777L, P780ins, V842I, and R896C. HER2 in-frame deletion 755-759, which is homologous to EGF receptor (EGFR) exon 19 in-frame deletions, had a neomorphic phenotype with increased phosphorylation of EGFR or HER3. L755S produced lapatinib resistance, but was not an activating mutation in our experimental systems. All of these mutations were sensitive to the irreversible kinase inhibitor, neratinib. These findings show that HER2 somatic mutation is an alternative mechanism to activate HER2 in breast cancer and they validate HER2 somatic mutations as drug targets for breast cancer treatment. We show that the majority of HER2 somatic mutations in breast cancer patients are activating mutations that likely drive tumorigenesis. Several patients had mutations that are resistant to the reversible HER2 inhibitor lapatinib, but are sensitive to the irreversible HER2 inhibitor, neratinib. Our results suggest that patients with HER2 mutation–positive breast cancers could benefit from existing HER2-targeted drugs.

  5. Herceptin Enhances the Antitumor Effect of Natural Killer Cells on Breast Cancer Cells Expressing Human Epidermal Growth Factor Receptor-2.

    PubMed

    Tian, Xiao; Wei, Feng; Wang, Limei; Yu, Wenwen; Zhang, Naining; Zhang, Xinwei; Han, Ying; Yu, Jinpu; Ren, Xiubao

    2017-01-01

    Optimal adoptive cell therapy (ACT) should contribute to effective cancer treatment. The unique ability of natural killer (NK) cells to kill cancer cells independent of major histocompatibility requirement makes them suitable as ACT tools. Herceptin, an antihuman epidermal growth factor receptor-2 (anti-HER2) monoclonal antibody, is used to treat HER2 + breast cancer. However, it has limited effectiveness and possible severe cardiotoxicity. Given that Herceptin may increase the cytotoxicity of lymphocytes, we explored the possible augmentation of NK cell cytotoxicity against HER2 + breast cancer cells by Herceptin. We demonstrated that Herceptin could interact with CD16 on NK cells to expand the cytotoxic NK (specifically, CD56 dim ) cell population. Additionally, Herceptin increased NK cell migration and cytotoxicity against HER2 + breast cancer cells. In a pilot study, Herceptin-treated NK cells shrunk lung nodular metastasis in a woman with HER2 + breast cancer who could not tolerate the cardiotoxic side effects of Herceptin. Our findings support the therapeutic potential of Herceptin-treated NK cells in patients with HER2 + and Herceptin-intolerant breast cancer.

  6. The efficacy of adjuvant trastuzumab in HER-2 positive breast cancer with axillary lymph node metastases according to the treatment duration.

    PubMed

    Sendur, Mehmet A N; Aksoy, Sercan; Ozdemir, Nuriye Y; Yazici, Ozan; Zengin, Nurullah; Altundag, Kadri

    2014-12-01

    Trastuzumab is the first anti-HER-2 humanized monoclonal antibody. The benefit of adjuvant trastuzumab has been shown in randomized phase III trials. Despite trastuzumab being recommended for 52 weeks in the adjuvant treatment of HER-2 positive breast cancer according to the current breast cancer guidelines, there is still no consensus on the optimal duration of adjuvant trastuzumab. The aim of our study is to investigate the efficacy and safety of adjuvant trastuzumab for 9 weeks and 52 weeks in axillary lymph node positive HER-2 positive breast cancer patients. A total of 271 HER-2 and axillary node positive breast cancer patients who received trastuzumab in adjuvant treatment between the years 2005 and 2013 were retrospectively analyzed. Patients with axillary node positive HER-2 positive breast cancer who were non-metastatic were enrolled to the study. Patients were allocated to the 9 week trastuzumab group (n = 155) or the 52 week trastuzumab group (n = 116). Kaplan-Meier survival analysis was carried out for disease free survival (DFS) and overall survival (OS). Two-sided p values of <0.05 were considered statistically significant. The most important limitation of our manuscript is the retrospective design. The median follow-up time for this analysis was 34 (4-95) months. Patients' clinical and pathological characteristics were well balanced between the two treatment arms. In the 9 week trastuzumab treatment group, the DFS rate was 96.7%, 84.8% and 74.9% in the first, third and fifth years respectively, whereas in the 52 week trastuzumab treatment group it was 94.3%, 80.0% and 80.0% (P = 0.76). In the 9 week trastuzumab treatment group, the OS rate was 99.3%, 92.2% and 88.3% in the first, third and fifth years respectively, whereas in the 52 week trastuzumab treatment group it was 99.0%, 94.7% and 78.6% (P = 0.99). In both groups, symptomatic heart failure was not reported but asymptomatic left ventricular ejection fraction (LVEF) decline was observed 3 (1

  7. An anti-G protein monoclonal antibody treats RSV disease more effectively than an anti-F monoclonal antibody in BALB/c mice.

    PubMed

    Boyoglu-Barnum, Seyhan; Todd, Sean O; Chirkova, Tatiana; Barnum, Thomas R; Gaston, Kelsey A; Haynes, Lia M; Tripp, Ralph A; Moore, Martin L; Anderson, Larry J

    2015-09-01

    Respiratory syncytial virus (RSV) belongs to the family Paramyxoviridae and is the single most important cause of serious lower respiratory tract infections in young children, yet no highly effective treatment or vaccine is available. To clarify the potential for an anti-G mAb, 131-2G which has both anti-viral and anti-inflammatory effects, to effectively treat RSV disease, we determined the kinetics of its effect compared to the effect of the anti-F mAb, 143-6C on disease in mice. Treatment administered three days after RSV rA2-line19F (r19F) infection showed 131-2G decreased breathing effort, pulmonary mucin levels, weight loss, and pulmonary inflammation earlier and more effectively than treatment with mAb 143-6C. Both mAbs stopped lung virus replication at day 5 post-infection. These data show that, in mice, anti-G protein mAb is superior to treating disease during RSV infection than an anti-F protein mAb similar to Palivizumab. This combination of anti-viral and anti-inflammatory activity makes 131-2G a promising candidate for treating for active human RSV infection. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Updated 2013 College of American Pathologists/American Society of Clinical Oncology (CAP/ASCO) guideline recommendations for human epidermal growth factor receptor 2 (HER2) fluorescent in situ hybridization (FISH) testing increase HER2 positive and HER2 equivocal breast cancer cases; retrospective study of HER2 FISH results of 836 invasive breast cancers.

    PubMed

    Singh, Kamaljeet; Tantravahi, Umadevi; Lomme, Michele M; Pasquariello, Terese; Steinhoff, Margaret; Sung, C James

    2016-06-01

    For dual probe HER2 FISH assay, the 2013 CAP/ASCO guideline recommendations lowered the HER2/CEP17 ratio cut off for HER2 amplification to ≥2.0 and introduced an average HER2 copy number criterion for HER2 amplification (≥6.0/cell) and HER2 equivocal categories (≥4 and <6/cell). The HER2/CEP17 equivocal category is eliminated. The aim of this study is to assess the impact of 2013 HER2 FISH testing guideline recommendations update on the assignment of HER2 status with dual probe HER2 FISH assay. Dual probe HER2 FISH assay results on breast cancers from 09/2009 to 07/2015 that underwent reflex HER2 FISH testing after equivocal HER2 (2+) immunohistochemistry (IHC) were reviewed. HER2 copy number, CEP17 signals, and HER2/CEP ratios were noted. HER2 status was assigned as HER2 negative (HER2-), HER2 equivocal (HER2e), and HER2 amplified (HER2+) by applying both 2007 and 2013 CAP/ASCO HER2 FISH guideline recommendations and results were compared. New guidelines reclassified HER2 FISH status in a significant proportion of cases (8.3 %, 69/836; p = .021). There were 22 (2.6 %) more HER2+, 17 (2.1 %) more HER2e, and 39 (4.1 %) fewer HER2- tumors. Change of HER2 status correlated significantly with ≥3 CEP17 signals (38 vs. 2 %; p < .001). The 2013 CAP/ASCO guideline recommendations for HER2 FISH testing by dual probe assay increased the HER2 amplified and HER2 equivocal tumors. Increase in HER2 equivocal tumors would potentially increase the frequency of repeat HER2 testing. Tumors with ≥3 CEP17 signals, so-called chromosome 17 polysomy, are more likely to be impacted and classified as HER2 equivocal.

  9. A Comprehensive Outline of Trastuzumab Resistance Biomarkers in HER2 Overexpressing Breast Cancer.

    PubMed

    Menyhárt, Otília; Santarpia, Libero; Győrffy, Balázs

    2015-01-01

    The introduction of trastuzumab for anti-HER2 therapy dramatically changed the clinical outcome for HER2 (ERBB2, neu) positive breast cancer patients. Today, patients eligible for trastuzumab are selected using HER2 expression/amplification status of the primary tumor. However, acquired and inherent resistance to anti-HER2 therapy in these patients poses a significant challenge, and better patient stratification will be needed to improve clinical response. Here, we provide a wide-ranging overview of potential biomarkers capable of stratifying patients regarding their response to trastuzumab. These include HER2 amplification, impaired access to the binding site (p95HER2, Δ16HER-2, MUC4), augmented signaling through other ERBB family receptors (HER1, HER3, HER4) and their ligands, activation of HER2 targets by alternate heterodimers (EphA2, IGF-1R, GDF15, MUC1*), signaling triggered by downstream members (PIK3CA, PTEN, SRC, mTOR), altered expression of cell cycle and apoptotic regulators (CDKs, p27(kip1), Bcl-2), hormone receptor status, resistance to antibody-dependent cellular cytotoxicity (FcγR), and altered miRNA expression signatures. Multigenic molecular profile analyses have revealed further genes not directly associated with classical oncogenic pathways. Although numerous biomarkers have shown promise in pre-clinical studies, many have delivered controversial results when evaluated in clinical trials. One of the keys for targeting ERBB2 will be to consider the entire ERBB family and downstream associated pathways responsible for the malignant transformation. The heterogeneity of the disease is likely to represent a significant obstacle to accurately predicting the course of resistance. The future most probably involves the incorporation of multiple biomarkers into a unified predictor enabling selection of patients for superior targeted drug administration.

  10. The effects of a repeated dose of a recombinant humanized anti-cocaine monoclonal antibody on cocaine self-administration in rats.

    PubMed

    Wetzel, Hanna N; Tsibulsky, Vladimir L; Norman, Andrew B

    2016-11-01

    Immunotherapy has shown potential as a treatment for cocaine abuse. The humanized recombinant anti-cocaine monoclonal antibody (mAb) with the preclinical designation h2E2 has been shown to decrease cocaine concentrations in the brain in rats, but its effects on cocaine self-administration behavior have never been tested. The amount of cocaine needed to reinstate self-administration behavior (priming threshold) was calculated and the inter-injection intervals at unit doses of 0.3μmol/kg and 3μmol/kg during maintained self-administration were measured over a five-week baseline period. Rats trained to self-administer cocaine were infused with two doses of h2E2 (120mg/kg i.v.) 35days apart. Priming threshold and inter-injection intervals were measured for 35days after both injections. After both injections of h2E2, priming thresholds were significantly increased (3-fold) compared to expected baseline and then gradually declined over 35days. A significant decrease (15-33%) in inter-injection intervals during maintained self-administration was also observed following both h2E2 infusions at the lower dose, and after the first injection at the higher dose. No significant decreases in body weight were observed after either injection, indicating a lack of toxicity following a second injection. These data predict that the safety and effectiveness of h2E2 will be maintained after multiple treatments of this potential immunotherapy for cocaine abuse. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. The effects of a repeated dose of a recombinant humanized anti-cocaine monoclonal antibody on cocaine self-administration in rats

    PubMed Central

    Wetzel, Hanna N.; Tsibulsky, Vladimir L.; Norman, Andrew B.

    2016-01-01

    Background Immunotherapy has shown potential as a treatment for cocaine abuse. The humanized recombinant anti-cocaine monoclonal antibody (mAb) with the preclinical designation h2E2 has been shown to decrease cocaine concentrations in the brain in rats, but its effects on cocaine self-administration behavior have never been tested. Methods The amount of cocaine needed to reinstate self-administration behavior (priming threshold) was calculated and the inter-injection intervals at unit doses of 0.3 μmol/kg and 3 μmol/kg during maintained self-administration were measured over a five-week baseline period. Rats trained to self-administer cocaine were infused with two doses of h2E2 (120 mg/kg i.v.) 35 days apart. Priming threshold and inter-injection intervals were measured for 35 days after both injections. Results After both injections of h2E2, priming thresholds were significantly increased (3-fold) compared to expected baseline and then gradually declined over 35 days. A significant decrease (15–33%) in inter-injection intervals during maintained self-administration was also observed following both h2E2 at the lower dose, and after the first injection at the higher dose. No significant decreases in body weight were observed after either injection, indicating a lack of toxicity following a second injection. Conclusions These data predict that the safety and efficacy of h2E2 will be maintained after multiple treatments of this potential immunotherapy for cocaine abuse. PMID:27736682

  12. Antiproliferative effects of γ-tocotrienol are associated with lipid raft disruption in HER2-positive human breast cancer cells.

    PubMed

    Alawin, Osama A; Ahmed, Rayan A; Ibrahim, Baher A; Briski, Karen P; Sylvester, Paul W

    2016-01-01

    A large percentage of human breast cancers are characterized by excessive or aberrant HER2 activity. Lipid rafts are specialized microdomains within the plasma membrane that are required for HER2 activation and signal transduction. Since the anticancer activity of γ-tocotrienol is associated with suppression in HER2 signaling, studies were conducted to examine the effects of γ-tocotrienol on HER2 activation within the lipid raft microdomain in HER2-positive SKBR3 and BT474 human breast cancer cells. Treatment with 0-5μM γ-tocotrienol induced a significant dose-dependent inhibition in cancer cell growth after a 5-day culture period, and these growth inhibitory effects were associated with a reduction in HER2 dimerization and phosphorylation (activation). Phosphorylated HER2 was found to be primarily located in the lipid raft microdomain of the plasma membrane in vehicle-treated control groups, whereas γ-tocotrienol treatment significantly inhibited this effect. Assay of plasma membrane subcellular fractions showed that γ-tocotrienol also accumulates exclusively within the lipid raft microdomain. Hydroxypropyl-β-cyclodextrin (HPβCD) is an agent that disrupts lipid raft integrity. Acute exposure to 3mM HPβCD alone had no effect, whereas an acute 24-h exposure to 20μM γ-tocotrienol alone significantly decreased SKBR3 and BT474 cell viability. However, combined treatment with these agents greatly reduced γ-tocotrienol accumulation in the lipid raft microdomain and cytotoxicity. In summary, these findings demonstrate that the anticancer effects of γ-tocotrienol are associated with its accumulation in the lipid raft microdomain and subsequent interference with HER2 dimerization and activation in SKBR3 and BT474 human breast cancer cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Anti-myeloperoxidase autoantibodies react with native but not denatured myeloperoxidase.

    PubMed Central

    Falk, R J; Becker, M; Terrell, R; Jennette, J C

    1992-01-01

    We wondered whether anti-myeloperoxidase (MPO) autoantibodies (MPO-ANCA) found in patients with systemic vasculitis react with a conformational epitope or epitopes on the MPO molecule. Sera from 15 human MPO-ANCA, and a polyclonal and a monoclonal anti-MPO antibodies were reacted with MPO in native and denatured states. Human MPO-ANCA and mouse monoclonal anti-MPO reacted with native MPO, and a 120-kD band representing the MPO hologenzyme, but not with denatured MPO fragments; however, MPO-ANCA and mouse anti-MPO did not demonstrate competitive inhibition of binding to MPO. Polyclonal rabbit anti-MPO reacted with both native and denatured MPO. All MPO-ANCA tested showed the same patterns of reactivity with native and denatured MPO in dot blot and Western blot analyses. Both polyclonal and monoclonal anti-MPO antibodies inhibited MPO's protein iodination by over 90%, whereas MPO-ANCA IgGs, normal IgGs and disease control IgGs did not. These data suggest that (i) MPO-ANCA interact with a conformational epitope on the MPO molecule; and (ii) MPO-ANCA from different patients have similar reactivity with native versus denatured MPO. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:1379133

  14. HER2 missense mutations have distinct effects on oncogenic signaling and migration

    PubMed Central

    Zabransky, Daniel J.; Yankaskas, Christopher L.; Cochran, Rory L.; Wong, Hong Yuen; Croessmann, Sarah; Chu, David; Kavuri, Shyam M.; Red Brewer, Monica; Rosen, D. Marc; Dalton, W. Brian; Cimino-Mathews, Ashley; Cravero, Karen; Button, Berry; Kyker-Snowman, Kelly; Cidado, Justin; Erlanger, Bracha; Parsons, Heather A.; Manto, Kristen M.; Bose, Ron; Lauring, Josh; Arteaga, Carlos L.; Konstantopoulos, Konstantinos; Park, Ben Ho

    2015-01-01

    Recurrent human epidermal growth factor receptor 2 (HER2) missense mutations have been reported in human cancers. These mutations occur primarily in the absence of HER2 gene amplification such that most HER2-mutant tumors are classified as “negative” by FISH or immunohistochemistry assays. It remains unclear whether nonamplified HER2 missense mutations are oncogenic and whether they are targets for HER2-directed therapies that are currently approved for the treatment of HER2 gene-amplified breast cancers. Here we functionally characterize HER2 kinase and extracellular domain mutations through gene editing of the endogenous loci in HER2 nonamplified human breast epithelial cells. In in vitro and in vivo assays, the majority of HER2 missense mutations do not impart detectable oncogenic changes. However, the HER2 V777L mutation increased biochemical pathway activation and, in the context of a PIK3CA mutation, enhanced migratory features in vitro. However, the V777L mutation did not alter in vivo tumorigenicity or sensitivity to HER2-directed therapies in proliferation assays. Our results suggest the oncogenicity and potential targeting of HER2 missense mutations should be considered in the context of cooperating genetic alterations and provide previously unidentified insights into functional analysis of HER2 mutations and strategies to target them. PMID:26508629

  15. Mass-Production and Characterization of Anti-CD20 Monoclonal Antibody in Peritoneum of Balb/c Mice

    PubMed Central

    Sineh sepehr, Koushan; Baradaran, Behzad; Majidi, Jafar; Abdolalizadeh, Jalal; Aghebati, leili; Zare Shahneh, Fatemeh

    2013-01-01

    Purpose: Monoclonal antibodies are important tools are used in basic research as well as, in diagnosis, imaging and treatment of immunodeficiency diseases, infections and cancers. The purpose of this study was to produce large scale of monoclonal antibody against CD20 in order to diagnostic application in leukemia and lymphomas disorders. Methods: Hybridoma cells that produce monoclonal antibody against human CD20 were administered into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. After twelve days, approximately 7 ml ascetic fluid was harvested from the peritoneum of each mouse. Evaluation of mAb titration was assessed by ELISA method. In the present study, we describe a protocol for large scale production of MAbs. Results: We prepared monoclonal antibodies (mAbs) with high specificity and sensitivity against human CD20 by hybridoma method and characterized them by ELISA. The subclass of antibody was IgG2a and its light chain was kappa. Ascetic fluid was purified by Protein-A Sepharose affinity chromatography and the purified monoclonal antibody was conjugated with FITC and Immunofluorescence was done for confirming the specific binding. Conclusion: The conjugated monoclonal antibody could have application in diagnosis B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells. PMID:24312821

  16. Neratinib overcomes trastuzumab resistance in HER2 amplified breast cancer

    PubMed Central

    Mullooly, Maeve; Bennett, Ruth; Bouguern, Noujoude; Pedersen, Kasper; O'Brien, Neil A; Roxanis, Ioannis; Li, Ji-Liang; Bridge, Esther; Finn, Richard; Slamon, Dennis; McGowan, Patricia; Duffy, Michael J.

    2013-01-01

    Trastuzumab has been shown to improve the survival outcomes of HER2 positive breast cancer patients. However, a significant proportion of HER2-positive patients are either inherently resistant or develop resistance to trastuzumab. We assessed the effects of neratinib, an irreversible panHER inhibitor, in a panel of 36 breast cancer cell lines. We further assessed its effects with or without trastuzumab in several sensitive and resistant breast cancer cells as well as a BT474 xenograft model. We confirmed that neratinib was significantly more active in HER2-amplified than HER2 non-amplified cell lines. Neratinib decreased the activation of the 4 HER receptors and inhibited downstream pathways. However, HER3 and Akt were reactivated at 24 hours, which was prevented by the combination of trastuzumab and neratinib. Neratinib also decreased pHER2 and pHER3 in acquired trastuzumab resistant cells. Neratinib in combination with trastuzumab had a greater growth inhibitory effect than either drug alone in 4 HER2 positive cell lines. Furthermore, trastuzumab in combination with neratinib was growth inhibitory in SKBR3 and BT474 cells which had acquired resistance to trastuzumab as well as in a BT474 xenograft model. Innately trastuzumab resistant cell lines showed sensitivity to neratinib, but the combination did not enhance response compared to neratinib alone. Levels of HER2 and phospho-HER2 showed a direct correlation with sensitivity to neratinib. Our data indicate that neratinib is an effective anti-HER2 therapy and counteracted both innate and acquired trastuzumab resistance in HER2 positive breast cancer. Our results suggest that combined treatment with trastuzumab and neratinib is likely to be more effective than either treatment alone for both trastuzumab-sensitive breast cancer as well as HER2-positive tumors with acquired resistance to trastuzumab. PMID:24009064

  17. Neratinib overcomes trastuzumab resistance in HER2 amplified breast cancer.

    PubMed

    Canonici, Alexandra; Gijsen, Merel; Mullooly, Maeve; Bennett, Ruth; Bouguern, Noujoude; Pedersen, Kasper; O'Brien, Neil A; Roxanis, Ioannis; Li, Ji-Liang; Bridge, Esther; Finn, Richard; Siamon, Dennis; McGowan, Patricia; Duffy, Michael J; O'Donovan, Norma; Crown, John; Kong, Anthony

    2013-10-01

    Trastuzumab has been shown to improve the survival outcomes of HER2 positive breast cancer patients. However, a significant proportion of HER2-positive patients are either inherently resistant or develop resistance to trastuzumab. We assessed the effects of neratinib, an irreversible panHER inhibitor, in a panel of 36 breast cancer cell lines. We further assessed its effects with or without trastuzumab in several sensitive and resistant breast cancer cells as well as a BT474 xenograft model. We confirmed that neratinib was significantly more active in HER2-amplified than HER2 non-amplified cell lines. Neratinib decreased the activation of the 4 HER receptors and inhibited downstream pathways. However, HER3 and Akt were reactivated at 24 hours, which was prevented by the combination of trastuzumab and neratinib. Neratinib also decreased pHER2 and pHER3 in acquired trastuzumab resistant cells. Neratinib in combination with trastuzumab had a greater growth inhibitory effect than either drug alone in 4 HER2 positive cell lines. Furthermore, trastuzumab in combination with neratinib was growth inhibitory in SKBR3 and BT474 cells which had acquired resistance to trastuzumab as well as in a BT474 xenograft model. Innately trastuzumab resistant cell lines showed sensitivity to neratinib, but the combination did not enhance response compared to neratinib alone. Levels of HER2 and phospho-HER2 showed a direct correlation with sensitivity to neratinib. Our data indicate that neratinib is an effective anti-HER2 therapy and counteracted both innate and acquired trastuzumab resistance in HER2 positive breast cancer. Our results suggest that combined treatment with trastuzumab and neratinib is likely to be more effective than either treatment alone for both trastuzumab-sensitive breast cancer as well as HER2-positive tumors with acquired resistance to trastuzumab.

  18. Potency of a human monoclonal antibody to diphtheria toxin relative to equine diphtheria anti-toxin in a guinea pig intoxication model

    PubMed Central

    Smith, Heidi L.; Cheslock, Peter; Leney, Mark; Barton, Bruce; Molrine, Deborah C.

    2016-01-01

    ABSTRACT Prompt administration of anti-toxin reduces mortality following Corynebacterium diphtheriae infection. Current treatment relies upon equine diphtheria anti-toxin (DAT), with a 10% risk of serum sickness and rarely anaphylaxis. The global DAT supply is extremely limited; most manufacturers have ceased production. S315 is a neutralizing human IgG1 monoclonal antibody to diphtheria toxin that may provide a safe and effective alternative to equine DAT and address critical supply issues. To guide dose selection for IND-enabling pharmacology and toxicology studies, we dose-ranged S315 and DAT in a guinea pig model of diphtheria intoxication based on the NIH Minimum Requirements potency assay. Animals received a single injection of antibody premixed with toxin, were monitored for 30 days, and assigned a numeric score for clinical signs of disease. Animals receiving ≥ 27.5 µg of S315 or ≥ 1.75 IU of DAT survived whereas animals receiving ≤ 22.5 µg of S315 or ≤ 1.25 IU of DAT died, yielding a potency estimate of 17 µg S315/IU DAT (95% CI 16–21) for an endpoint of survival. Because some surviving animals exhibited transient limb weakness, likely a systemic sign of toxicity, DAT and S315 doses required to prevent hind limb paralysis were also determined, yielding a relative potency of 48 µg/IU (95% CI 38–59) for this alternate endpoint. To support advancement of S315 into clinical trials, potency estimates will be used to evaluate the efficacy of S315 versus DAT in an animal model with antibody administration after toxin exposure, more closely modeling anti-toxin therapy in humans. PMID:27070129

  19. AT-47PHASE I TRIAL OF INTRATHECAL TRASTUZUMAB IN HER2 POSITIVE LEPTOMENINGEAL METASTASES

    PubMed Central

    Raizer, Jeffrey; Pentsova, Elena; Omuro, Antonio; Lin, Nancy; Nayak, Lakshmi; Quant, Eudocia; Kumthekar, Priya

    2014-01-01

    INTRODUCTION: Trastuzimab is a humanized monoclonal antibody against Her2 whose limitation is central nervous system penetration that often leads to brain and leptomeningeal metastases (LM) in the setting to controlled systemic HER2 positive breast cancer. We performed a phase I clinical trial of intrathecal (IT) trastuzumab in patients with HER2 positive breast cancer and LM. METHODS: IRB consented patients were treated at defined dose levels; protocol was modified to accelerate dose escalation and increase IT dosage. Dose levels of IT treatment 10 mg, 20 mg, 40 mg, 60 mg and 80 mg were examined. Treatment was given twice a week x4 weeks, then once a week x4 weeks then every other week until progressive disease. MRI was done at 4 week intervals x2 then every 8 weeks. CSF was assessed every other week x2 then every 4 weeks. RESULTS: 13 women with HER2 positive breast cancer, 1 man with a glioblastoma, and one woman with anaplastic ependymoma were enrolled with a median age of 55 (42-67) and median KPS of 80 (60-90). Three patients were treated at the 10mg dose level, three at 20mg, one at 40mg, one at 60mg and 7 at 80mg. At the 80 mg dose level a patient was added as one patient was removed before complete evaluation and another patient had a grade 4 DLT of arachnoiditis. One patient had the Ommaya reservoir removed for infection unrelated to treatment. Data on CSF levels shows therapeutic levels in the patients treated with 10 mg, 20 mg and 40 mg; data analysis on CSF at 60 and 80 mg is pending. CONCLUSION: IT Trastuzumab is well tolerated up to 80 mg IT. Complete CSF PK data will be presented. A phase II study is underway at the 80 mg dose.

  20. Selective Inhibition of HER2-Positive Breast Cancer Cells by the HIV Protease Inhibitor Nelfinavir

    PubMed Central

    2012-01-01

    Background Human epidermal growth factor receptor 2 (HER2)–positive breast cancer is highly aggressive and has higher risk of recurrence than HER2-negative cancer. With few treatment options available, new drug targets specific for HER2-positive breast cancer are needed. Methods We conducted a pharmacological profiling of seven genotypically distinct breast cancer cell lines using a subset of inhibitors of breast cancer cells from a screen of the Johns Hopkins Drug Library. To identify molecular targets of nelfinavir, identified in the screen as a selective inhibitor of HER2-positive cells, we conducted a genome-wide screen of a haploinsufficiency yeast mutant collection. We evaluated antitumor activity of nelfinavir with xenografts in athymic nude mouse models (n = 4–6 per group) of human breast cancer and repeated mixed-effects regression analysis. All statistical tests were two-sided. Results Pharmacological profiling showed that nelfinavir, an anti-HIV drug, selectively inhibited the growth of HER2-positive breast cancer cells in vitro. A genome-wide screening of haploinsufficiency yeast mutants revealed that nelfinavir inhibited heat shock protein 90 (HSP90) function. Further characterization using proteolytic footprinting experiments indicated that nelfinavir inhibited HSP90 in breast cancer cells through a novel mechanism. In vivo, nelfinavir selectively inhibited the growth of HER2-positive breast cancer cells (tumor volume index of HCC1954 cells on day 29, vehicle vs nelfinavir, mean = 14.42 vs 5.16, difference = 9.25, 95% confidence interval [CI] = 5.93 to 12.56, P < .001; tumor volume index of BT474 cells on day 26, vehicle vs nelfinavir, mean = 2.21 vs 0.90, difference = 1.31, 95% CI = 0.83 to 1.78, P < .001). Moreover, nelfinavir inhibited the growth of trastuzumab- and/or lapatinib-resistant, HER2-positive breast cancer cells in vitro at clinically achievable concentrations. Conclusion Nelfinavir was found to be a new class of HSP90 inhibitor and

  1. A novel anti-EGFR monoclonal antibody inhibiting tumor cell growth by recognizing different epitopes from cetuximab.

    PubMed

    Hong, Kwang-Won; Kim, Chang-Goo; Lee, Seung-Hyun; Chang, Ki-Hwan; Shin, Yong Won; Ryoo, Kyung-Hwan; Kim, Se-Ho; Kim, Yong-Sung

    2010-01-01

    The epidermal growth factor receptor (EGFR) overexpressed in many epithelial tumors is an attractive target for tumor therapy since numerous blocking agents of EGFR signaling have proven their anti-tumor activity. Here we report a novel monoclonal antibody (mAb), A13, which was generated from mice immunized with human cervical carcinoma A431 cells. In addition to binding to soluble EGFR with affinity of K(D) approximately 5.8nM, mAb A13 specifically bound to a variety of tumor cells and human placenta tissues expressing EGFR. A13 efficiently inhibited both EGF-dependant EGFR tyrosine phosphorylation in cervical and breast tumor cells and also in vitro colony formation of EGFR-overexpressing lung tumors. Competition and sandwich ELISAs, competitive surface plasmon resonance, and domain-level epitope mapping analyses demonstrated that mAb A13 competitively bound to the domain III (amino acids 302-503) of EGFR with EGF, but recognized distinct epitopes from those of cetuximab (Erbitux). Our results demonstrated that anti-EGFR mAb A13 interfered with EGFR proliferation signaling by blocking EGF binding to EGFR with different epitopes from those of cetuximab, suggesting that combination therapies of mAb A13 with cetuximab may prove beneficial for anti-tumor therapy.

  2. Discovery of a Potential HER2 Inhibitor from Natural Products for the Treatment of HER2-Positive Breast Cancer

    PubMed Central

    Li, Jianzong; Wang, Haiyang; Li, Junjie; Bao, Jinku; Wu, Chuanfang

    2016-01-01

    Breast cancer is one of the most lethal types of cancer in women worldwide due to the late stage detection and resistance to traditional chemotherapy. The human epidermal growth factor receptor 2 (HER2) is considered as a validated target in breast cancer therapy. Even though a substantial effort has been made to develop HER2 inhibitors, only lapatinib has been approved by the U.S. Food and Drug Administration (FDA). Side effects were observed in a majority of the patients within one year of treatment initiation. Here, we took advantage of bioinformatics tools to identify novel effective HER2 inhibitors. The structure-based virtual screening combined with ADMET (absorption, distribution, metabolism, excretion and toxicity) prediction was explored. In total, 11,247 natural compounds were screened. The top hits were evaluated by an in vitro HER2 kinase inhibition assay. The cell proliferation inhibition effect of identified inhibitors was evaluated in HER2-overexpressing SKBR3 and BT474 cell lines. We found that ZINC15122021 showed favorable ADMET properties and attained high binding affinity against HER2. Moreover, ZINC15122021 showed high kinase inhibition activity against HER2 and presented outstanding cell proliferation inhibition activity against both SKBR3 and BT474 cell lines. Results reveal that ZINC15122021 can be a potential HER2 inhibitor. PMID:27376283

  3. Therapeutic implication of HER2 in advanced biliary tract cancer

    PubMed Central

    Cha, Yongjun; Ha, Hyerim; Park, Ji Eun; Bang, Ju-Hee; Jin, Mei Hua; Lee, Kyung-Hun; Kim, Tae-Yong; Han, Sae-Won; Im, Seock-Ah; Kim, Tae-You; Oh, Do-Youn; Bang, Yung-Jue

    2016-01-01

    Currently, there is no validated therapeutic target for biliary tract cancer (BTC). This study aimed to investigate the pre-clinical and clinical implication of HER2 as a therapeutic target in BTC. We established two novel HER2-amplified BTC cell lines, SNU-2670 and SNU-2773, from gallbladder cancer patients. SNU-2670 and SNU-2773 cells were sensitive to trastuzumab, dacomitinib, and afatinib compared with nine HER2-negative BTC cell lines. Dacomitinib and afatinib led to G1 cell cycle arrest in SNU-2773 cells and apoptosis in SNU-2670 cells. Furthermore, dacomitinib, afatinib, and trastuzumab showed synergistic cytotoxicity when combined with some cytotoxic drugs including gemcitabine, cisplatin, paclitaxel, and 5-fluorouracil. In a SNU-2670 mouse xenograft model, trastuzumab demonstrated a good anti-tumor effect as a monotherapy and in combination with gemcitabine increasing apoptosis. In our clinical data, 13.0% of patients with advanced BTC were defined as HER2-positive. Of these, three patients completed HER2-targeted chemotherapy. Two of them demonstrated a partial response, and the other one showed stable disease for 18 weeks. In summary, these pre-clinical and clinical data suggest that HER2 could be a therapeutic target, and that a HER2-targeting strategy should be developed further in patients with HER2-positive advanced BTC. PMID:27517322

  4. Anti-EGFR monoclonal antibody in cancer treatment: in vitro and in vivo evidence

    PubMed

    Quatrale, Anna Elisa; Petriella, Daniela; Porcelli, Letizia; Tommasi, Stefania; Silvestris, Nicola; Colucci, Giuseppe; Angelo, Angelo; Azzariti, Amalia

    2011-01-01

    The complexity of EGFR signaling network suggests that the receptor could be promising targets for new personalised therapy. In clinical practice two strategies targeting the receptor are available; they utilise monoclonal antibodies, directed towards the extracellular domain of EGFR, and small molecule tyrosine kinase inhibitors, which bind the catalytic kinase domain of the receptor. In this review, we summarise currently known pre-clinical data on the antitumor effects of monoclonal antibodies, which bind to EGFR in its inactive configuration, competing for ligand binding and thereby blocking ligand-induced EGFR tyrosine kinase activation. As a consequence of treatment, key EGFR-dependent intracellular signals in cancer cells are affected. Data explaining the mechanisms of action of anti-EGFR monoclonal antibodies, currently used in clinical setting and under development for the treatment of solid tumors, are revised with the aim to provide an overview of the most important preclinical studies showing the impact of this class of EGFR targeted agents on tumor biology.

  5. Monoclonal antibodies and human sera directed to the secreted glycoprotein G of herpes simplex virus type 2 recognize type-specific antigenic determinants.

    PubMed

    Liljeqvist, Jan-Ake; Trybala, Edward; Hoebeke, Johan; Svennerholm, Bo; Bergström, Tomas

    2002-01-01

    Glycoprotein G-2 (gG-2) of herpes simplex virus type 2 (HSV-2) is cleaved to a secreted amino-terminal portion (sgG-2) and to a cell-associated carboxy-terminal portion which is further O-glycosylated to constitute the mature gG-2 (mgG-2). In contrast to mgG-2, which is known to elicit a type-specific antibody response in the human host, information on the immunogenic properties of sgG-2 is lacking. Here the sgG-2 protein was purified on a heparin column and used for production of monoclonal antibodies (mAbs). Four anti-sgG-2 mAbs were mapped using a Pepscan technique and identified linear epitopes which localized to the carboxy-terminal part of the protein. One additional anti-sgG-2 mAb, recognizing a non-linear epitope, was reactive to three discrete peptide stretches where the most carboxy-terminally located stretch was constituted by the amino acids (320)RRAL(323). Although sgG-2 is rapidly secreted into the cell-culture medium after infection, the anti-sgG-2 mAbs identified substantial amounts of sgG-2 in the cytoplasm of HSV-2-infected cells. All of the anti-sgG-2 mAbs were HSV-2 specific showing no cross-reactivity to HSV-1 antigen or to HSV-1-infected cells. Similarly, sera from 50 HSV-2 isolation positive patients were all reactive to sgG-2 in an enzyme immunoassay whilst no reactivity was seen in 25 sera from HSV-1 isolation positive patients or in 25 serum samples from HSV-negative patients suggesting that sgG-2 is a novel antigen potentially suitable for type-discriminating serodiagnosis.

  6. Anti-HER2 IgY antibody-functionalized single-walled carbon nanotubes for detection and selective destruction of breast cancer cells

    PubMed Central

    2009-01-01

    Background Nanocarrier-based antibody targeting is a promising modality in therapeutic and diagnostic oncology. Single-walled carbon nanotubes (SWNTs) exhibit two unique optical properties that can be exploited for these applications, strong Raman signal for cancer cell detection and near-infrared (NIR) absorbance for selective photothermal ablation of tumors. In the present study, we constructed a HER2 IgY-SWNT complex and demonstrated its dual functionality for both detection and selective destruction of cancer cells in an in vitro model consisting of HER2-expressing SK-BR-3 cells and HER2-negative MCF-7 cells. Methods The complex was constructed by covalently conjugating carboxylated SWNTs with anti-HER2 chicken IgY antibody, which is more specific and sensitive than mammalian IgGs. Raman signals were recorded on Raman spectrometers with a laser excitation at 785 nm. NIR irradiation was performed using a diode laser system, and cells with or without nanotube treatment were irradiated by 808 nm laser at 5 W/cm2 for 2 min. Cell viability was examined by the calcein AM/ethidium homodimer-1 (EthD-1) staining. Results Using a Raman optical microscope, we found the Raman signal collected at single-cell level from the complex-treated SK-BR-3 cells was significantly greater than that from various control cells. NIR irradiation selectively destroyed the complex-targeted breast cancer cells without harming receptor-free cells. The cell death was effectuated without the need of internalization of SWNTs by the cancer cells, a finding that has not been reported previously. Conclusion We have demonstrated that the HER2 IgY-SWNT complex specifically targeted HER2-expressing SK-BR-3 cells but not receptor-negative MCF-7 cells. The complex can be potentially used for both detection and selective photothermal ablation of receptor-positive breast cancer cells without the need of internalization by the cells. Thus, the unique intrinsic properties of SWNTs combined with high

  7. Anti-HER2 IgY antibody-functionalized single-walled carbon nanotubes for detection and selective destruction of breast cancer cells.

    PubMed

    Xiao, Yan; Gao, Xiugong; Taratula, Oleh; Treado, Stephen; Urbas, Aaron; Holbrook, R David; Cavicchi, Richard E; Avedisian, C Thomas; Mitra, Somenath; Savla, Ronak; Wagner, Paul D; Srivastava, Sudhir; He, Huixin

    2009-10-02

    Nanocarrier-based antibody targeting is a promising modality in therapeutic and diagnostic oncology. Single-walled carbon nanotubes (SWNTs) exhibit two unique optical properties that can be exploited for these applications, strong Raman signal for cancer cell detection and near-infrared (NIR) absorbance for selective photothermal ablation of tumors. In the present study, we constructed a HER2 IgY-SWNT complex and demonstrated its dual functionality for both detection and selective destruction of cancer cells in an in vitro model consisting of HER2-expressing SK-BR-3 cells and HER2-negative MCF-7 cells. The complex was constructed by covalently conjugating carboxylated SWNTs with anti-HER2 chicken IgY antibody, which is more specific and sensitive than mammalian IgGs. Raman signals were recorded on Raman spectrometers with a laser excitation at 785 nm. NIR irradiation was performed using a diode laser system, and cells with or without nanotube treatment were irradiated by 808 nm laser at 5 W/cm2 for 2 min. Cell viability was examined by the calcein AM/ethidium homodimer-1 (EthD-1) staining. Using a Raman optical microscope, we found the Raman signal collected at single-cell level from the complex-treated SK-BR-3 cells was significantly greater than that from various control cells. NIR irradiation selectively destroyed the complex-targeted breast cancer cells without harming receptor-free cells. The cell death was effectuated without the need of internalization of SWNTs by the cancer cells, a finding that has not been reported previously. We have demonstrated that the HER2 IgY-SWNT complex specifically targeted HER2-expressing SK-BR-3 cells but not receptor-negative MCF-7 cells. The complex can be potentially used for both detection and selective photothermal ablation of receptor-positive breast cancer cells without the need of internalization by the cells. Thus, the unique intrinsic properties of SWNTs combined with high specificity and sensitivity of IgY antibodies

  8. Predictive value of quantitative HER2, HER3 and p95HER2 levels in HER2-positive advanced breast cancer patients treated with lapatinib following progression on trastuzumab.

    PubMed

    Duchnowska, Renata; Sperinde, Jeff; Czartoryska-Arłukowicz, Bogumiła; Myśliwiec, Paulina; Winslow, John; Radecka, Barbara; Petropoulos, Christos; Demlova, Regina; Orlikowska, Marlena; Kowalczyk, Anna; Lang, Istvan; Ziółkowska, Barbara; Dębska-Szmich, Sylwia; Merdalska, Monika; Grela-Wojewoda, Aleksandra; Żawrocki, Anton; Biernat, Wojciech; Huang, Weidong; Jassem, Jacek

    2017-11-28

    Lapatinib is a HER1 and HER2 tyrosine kinase inhibitor (TKI) approved in second line treatment of advanced or metastatic breast cancer following progression on trastuzumab-containing therapy. Biomarkers for activity of lapatinib and other TKIs are lacking. Formalin-fixed, paraffin-embedded primary tumor samples were obtained from 189 HER2-positive patients treated with lapatinib plus capecitabine following progression on trastuzumab. The HERmark ® Breast Cancer Assay was used to quantify HER2 protein expression. HER3 and p95HER2 protein expression was quantified using the VeraTag ® technology. Overall survival (OS) was inversely correlated with HER2 (HR = 1.9/log; P = 0.009) for patients with tumors above the cut-off positivity level by the HERmark assay. OS was significantly shorter for those with above median HER2 levels (HR = 1.7; P = 0.015) and trended shorter for those below the cut-off level of positivity by the HERmark assay (HR = 1.7; P = 0.057) compared to cases with moderate HER2 overexpression. The relationship between HER2 protein expression and OS was best captured with a U-shaped parabolic function (P = 0.004), with the best prognosis at moderate levels of HER2 protein overexpression. In a multivariate model including HER2, increasing p95HER2 expression was associated with longer OS (HR = 0.35/log; P = 0.027). Continuous HER3 did not significantly correlate with OS. Patients with moderately overexpressed HER2 levels and high p95HER2 expression may have best outcomes while receiving lapatinib following progression on trastuzumab. Further study is warranted to explore the predictive utility of quantitative HER2 and p95HER2 in guiding HER2-directed therapies.

  9. Clinical Translation and Validation of a Predictive Biomarker for Patritumab, an Anti-human Epidermal Growth Factor Receptor 3 (HER3) Monoclonal Antibody, in Patients With Advanced Non-small Cell Lung Cancer

    PubMed Central

    Mendell, Jeanne; Freeman, Daniel J.; Feng, Wenqin; Hettmann, Thore; Schneider, Matthias; Blum, Sabine; Ruhe, Jens; Bange, Johannes; Nakamaru, Kenji; Chen, Shuquan; Tsuchihashi, Zenta; von Pawel, Joachim; Copigneaux, Catherine; Beckman, Robert A.

    2015-01-01

    Background During early clinical development, prospective identification of a predictive biomarker and validation of an assay method may not always be feasible. Dichotomizing a continuous biomarker measure to classify responders also leads to challenges. We present a case study of a prospective–retrospective approach for a continuous biomarker identified after patient enrollment but defined prospectively before the unblinding of data. An analysis of the strengths and weaknesses of this approach and the challenges encountered in its practical application are also provided. Methods HERALD (NCT02134015) was a double-blind, phase 2 study in patients with non-small cell lung cancer (NSCLC) randomized to erlotinib with placebo or with high or low doses of patritumab, a monoclonal antibody targeted against human epidermal growth factor receptor 3 (HER3). While the primary objective was to assess safety and progression-free survival (PFS), a secondary objective was to determine a single predictive biomarker hypothesis to identify subjects most likely to benefit from the addition of patritumab. Although not identified as the primary biomarker in the study protocol, on the basis of preclinical results from 2 independent laboratories, expression levels of the HER3 ligand heregulin (HRG) were prospectively declared the predictive biomarker before data unblinding but after subject enrollment. An assay to measure HRG mRNA was developed and validated. Other biomarkers, such as epidermal growth factor receptor (EGFR) mutation status, were also evaluated in an exploratory fashion. The cutoff value for high vs. low HRG mRNA levels was set at the median delta threshold cycle. A maximum likelihood analysis was performed to evaluate the provisional cutoff. The relationship of HRG values to PFS hazard ratios (HRs) was assessed as a measure of internal validation. Additional NSCLC samples were analyzed to characterize HRG mRNA distribution. Results The subgroup of patients with high

  10. Development of a novel monoclonal antibody to human inducible co-stimulator ligand (ICOSL): Biological characteristics and application for enzyme-linked immunosorbent assay.

    PubMed

    Hu, Xiaohan; Wu, Jian; An, Jingnan; Hu, Yumin; Shen, Yu; Liu, Cuiping; Zhang, Xueguang

    2016-07-01

    ICOSL (B7-H2, CD275), a co-stimulatory molecule of the B7 superfamily, functions as a positive signal in immune response. To investigate whether ICOSL could be released into sera and the possible biological function of soluble ICOS (sICOSL), we generated and characterized a functional anti-human ICOSL monoclonal antibody (mAb), 20B10, and developed a novel enzyme-linked immunosorbent assay (ELISA) based on two anti-human ICOSL antibodies with different epitope specificities. Using the ELISA system, we found that sICOSL in the serum of healthy donors increases in an age-dependent manner and that the matrix metalloproteinase inhibitor (MMPI) could suppress sICOSL production. Together, these data demonstrate that the existence of circulating sICOSL in human serum might play an important role in immunoregulation. Copyright © 2016. Published by Elsevier B.V.

  11. Update on HER2 testing for breast and upper gastrointestinal tract cancers.

    PubMed

    Ross, Jeffrey S

    2011-06-01

    With the regulatory approvals in Europe and the USA of trastuzumab-based anti-HER2 targeted therapy for upper gastrointestinal cancers in 2010, HER2 testing has now become universal for newly diagnosed cases of both breast cancer and adenocarcinomas of esophagus, stomach and gastroesophageal origin. In the 12 years or more since the approval of trastuzumab for breast cancer, general refinements in approaches to HER2 testing, including a greater understanding of the implications of preanalytic factors impacting the test results and the application of standardization of reporting of HER2 test results, have taken place. There has also been continuing development in breast cancer with the introduction of new HER2 tests, including non-FISH tests, dimerization assays, phosphorylated HER2 receptor tests, mRNA-based tests, HER2 gene sequencing tests and the application of HER2 testing to circulating tumor cells. Most recently, the introduction of HER2 testing for upper gastrointentinal malignancies has emphasized the need for performing and interpreting slide-based assays in a manner unique to these specimens and not to apply the breast cancer testing protocols to esophageal and gastric adenocarcinomas.

  12. Activating HER2 mutations in HER2 gene amplification negative breast cancer

    PubMed Central

    Bose, Ron; Kavuri, Shyam M.; Searleman, Adam C.; Shen, Wei; Shen, Dong; Koboldt, Daniel C.; Monsey, John; Goel, Nicholas; Aronson, Adam B.; Li, Shunqiang; Ma, Cynthia X.; Ding, Li; Mardis, Elaine R.; Ellis, Matthew J.

    2012-01-01

    Data from eight breast cancer genome sequencing projects identified 25 patients with HER2 somatic mutations in cancers lacking HER2 gene amplification. To determine the phenotype of these mutations, we functionally characterized thirteen HER2 mutations using in vitro kinase assays, protein structure analysis, cell culture and xenograft experiments. Seven of these mutations are activating mutations, including G309A, D769H, D769Y, V777L, P780ins, V842I, and R896C. HER2 in-frame deletion 755-759, which is homologous to EGFR exon 19 in-frame deletions, had a neomorphic phenotype with increased phosphorylation of EGFR or HER3. L755S produced lapatinib resistance, but was not an activating mutation in our experimental systems. All of these mutations were sensitive to the irreversible kinase inhibitor, neratinib. These findings demonstrate that HER2 somatic mutation is an alternative mechanism to activate HER2 in breast cancer and they validate HER2 somatic mutations as drug targets for breast cancer treatment. PMID:23220880

  13. Efficacy of vaccination with plasmid DNA encoding for HER2/neu or HER2/neu-eGFP fusion protein against prostate cancer in rats.

    PubMed

    Bhattachary, R; Bukkapatnam, R; Prawoko, I; Soto, J; Morgan, M; Salup, R R

    2002-05-01

    Despite early diagnosis and improved therapy, 31,500 men will die from prostate cancer (PC) this year. The HER2/neu oncoprotein is an important effector of cell growth found in the majority of high-grade prostatic tumors and is capable of rendering immunogenicity. The antigenicity of this oncoprotein might prove useful in the development of PC vaccines. Our goal is to prove the principle that a single DNA vaccine can provide reliable immunity against PC in the MatLyLu (MLL) translational tumor model. The parental rat MatLyLu PC cell line expresses low to moderate levels of the rat neu protein. To simulate in vivo human PC, MatLyLu cells were transfected with a truncated sequence of human HER2/neu cDNA cloned into the pCI-neo vector. This HER2/neu cDNA sequence encodes the first 433 amino acids of the extracellular domain (ECD). MatLyLu cells were also transfected with the same HER2/neu cDNA sequence cloned into the N1-terminal sequence of EGFP reporter gene to produce a fusion protein. The partial ECD sequence of HER2/neu includes five rat major histocompatibility (MHC)-II-restricted peptides with complete human-to-rat cross-species homology. The HER2/neu protein overexpression was documented by Western Blot analysis, and the expression of fusion protein was monitored by confocal microscopy and fluorimetry. Vaccination with a single injection of HER2/neu cDNA protected 50% of animals against HER2/neu-MatLyLu tumors (P < 0.01). When the tumor cells were engineered to express HER2/neu-EGFP fusion protein, the antitumor immunity was enhanced, as following vaccination with HER2/neu-EGFP cDNA, 80% of these rats rejected HER2/neu-EGFP-MatLyLu (P<0.001). Both vaccines induced HER2/neu-specific antibody titers. Rats vaccinated with EGFP-cDNA rejected 80% of EGFP-MatLyLu tumors and, interestingly, 40% of HER2/neu-MatLyLu tumors. None of the cDNA vaccines induced immunity against parental MatLyLu cells. Our data clearly demonstrate that a single injection of HER2/neu-EGFP c

  14. Generation of monoclonal antibodies to a human natural killer clone. Characterization of two natural killer-associated antigens, NKH1A and NKH2, expressed on subsets of large granular lymphocytes.

    PubMed Central

    Hercend, T; Griffin, J D; Bensussan, A; Schmidt, R E; Edson, M A; Brennan, A; Murray, C; Daley, J F; Schlossman, S F; Ritz, J

    1985-01-01

    The initial characterization of two monoclonal antibodies directed at antigens selectively expressed on large granular lymphocytes (LGL) is reported in the present paper. These two reagents, anti-natural killer (NK) H1A and anti-NKH2, were obtained following immunization of mouse spleen cells with a cloned human NK cell line termed JT3. In fresh human peripheral blood, both anti-NKH1A and anti-NKH2 selectively reacted with cells that appeared morphologically as large granular lymphocytes. However, complement lysis studies and two color fluorescence analysis demonstrated that some LGL express both antigens and other cells express only NKH1A or NKH2. Functional analysis of these subsets indicated that the population of NKH1A+ cells contains the entire pool of NK active lymphocytes, whereas expression of NKH2 antigen appeared to delineate a unique subpopulation of LGL which, in a resting state, display a low degree of spontaneous cytotoxicity. Expression of NKH1A and NKH2 was also investigated using a series of nine well characterized human NK clones. All NK clones were found to be NKH1A+ and four out of nine also expressed NKH2. These results strongly supported the view that NKH1A is a "pan-NK" associated antigen, and indicated that at least a fraction of cloned NKH2 + LGL are strongly cytotoxic. Anti-NKH1A was shown to have the same specificity as the previously described N901 antibody and was found here to precipitate a 200,000-220,000-mol wt molecule in SDS-polyacrylamide gel electrophoresis (PAGE) analysis. Anti-NKH2 was specific for a structure that migrates at 60,000 mol wt in SDS-PAGE analysis under reducing conditions. Two color immunofluorescence analysis of NKH1A, NKH2, and other NK-associated antigens (Leu7 and B73.1) demonstrated variable degrees of coexpression of these antigens, which confirmed that NKH1A and NKH2 define distinct cell surface structures. Anti-NKH1A and anti-NKH2 appear to be useful reagents for characterizing LGL present in human

  15. A Randomized Phase 2 Trial of 177Lu Radiolabeled Anti-PSMA Monoclonal Antibody J591in Patients with High-Risk Castrate, Biochemically Relapsed Prostate Cancer

    DTIC Science & Technology

    2012-09-01

    micrometastases that may be targeted with radioimmunotherapy. Prostate specific membrane antigen (PSMA) is the single, most well-established, highly restricted...Radiolabeled anti- prostate specific membrane antigen (PSMA) monoclonal antibody J591 (177Lu-J591) for nonmetastatic castration-resistant prostate cancer...rationale for systemic salvage targeted anti- prostate specific membrane antigen radioimmunotherapy. Adv Urol 2012, Article ID 921674, doi:10.1155

  16. HER2, MET and FGFR2 oncogenic driver alterations define distinct molecular segments for targeted therapies in gastric carcinoma.

    PubMed

    Liu, Y J; Shen, D; Yin, X; Gavine, P; Zhang, T; Su, X; Zhan, P; Xu, Y; Lv, J; Qian, J; Liu, C; Sun, Y; Qian, Z; Zhang, J; Gu, Y; Ni, X

    2014-03-04

    Gastric cancer (GC) is a leading cause of cancer deaths worldwide. Since the approval of trastuzumab, targeted therapies are emerging as promising treatment options for the disease. This study aimed to explore the molecular segmentation of several known therapeutics targets, human epidermal growth factor receptor 2 (HER2), MET and fibroblast growth factor receptor 2 (FGFR2), within GC using clinically approved or investigational kits and scoring criteria. Knowledge of how these markers are segmented in the same cohort of GC patients could improve future clinical trial designs. Using immunohistochemistry (IHC) and FISH methods, overexpression and amplification of HER2, FGFR2 and MET were profiled in a cohort of Chinese GC samples. The correlations between anti-tumour sensitivity and the molecular segments of HER2, MET and FGFR2 alterations were further tested in a panel of GC cell lines and the patient-derived GC xenograft (PDGCX) model using the targeted inhibitors. Of 172 GC patients, positivity for HER2, MET and FGFR2 alternations was found in 23 (13.4%), 21 (12.2%) and 9 (5.2%) patients, respectively. Positivity for MET was found in 3 of 23 HER2-positive GC patients. Co-positivity for FGFR2 and MET was found in 1 GC patient, and amplification of the two genes was found in different tumour cells. Our study in a panel of GC cell lines showed that in most cell lines, amplification or high expression of a particular molecular marker was mutually exclusive and in vitro sensitivity to the targeted agents lapatinib, PD173074 and crizotinib was only observed in cell lines with the corresponding high expression of the drugs' target protein. SGC031, an MET-positive PDGCX mouse model, responded to crizotinib but not to lapatinib or PD173074. Human epidermal growth factor receptor 2, MET and FGFR2 oncogenic driver alterations (gene amplification and overexpression) occur in three largely distinct molecular segments in GC. A significant proportion of HER2-negative patients

  17. Functional Imaging of HER2-Positive Metastatic Breast Cancer Using 64Cu-DOTA-Trastuzumab Positron Emission Tomography

    PubMed Central

    Mortimer, Joanne E.; Bading, James R.; Colcher, David M.; Conti, Peter S.; Frankel, Paul H.; Carroll, Mary I.; Tong, Shan; Poku, Erasmus; Miles, Joshua K.; Shively, John E.; Raubitschek, Andrew A.

    2014-01-01

    Women with human epidermal growth factor receptor 2 (HER2)-positive breast cancer are candidates for treatment with the anti-HER2 antibody trastuzumab. Assessment of HER2 status in recurrent disease is usually made by core needle biopsy of a single lesion which may not be representative of the larger tumor mass or other sites of disease. Our long-range goal is to develop positron emission tomography (PET) of radiolabeled trastuzumab for systemically assessing tumor HER2 expression and identifying appropriate use of anti-HER2 therapies. The purpose of this study was to evaluate PET-CT of 64Cu-DOTA-trastuzumab for detecting and measuring tumor uptake of trastuzumab in patients with HER2-positive metastatic breast cancer. Methods Eight women with biopsy-confirmed HER2-positive metastatic breast cancer and no anti-HER2 therapy for ≥ 4 mo underwent complete staging, including 18F-fluorodeoxyglucose (FDG)/PET-CT. For 6 of the 8 patients, 64Cu-DOTA-trastuzumab injection (364-512 MBq, 5 mg trastuzumab) was preceded by trastuzumab infusion (45 mg). PET-CT (PET scan duration 1 h) was performed 21-25 (“Day 1”) and 47-49 (“Day 2”) h after 64Cu-DOTA-trastuzumab injection. Scan fields of view were chosen based on 18F-FDG/PET-CT. Lesions visualized relative to adjacent tissue on PET were considered PET-positive; analysis was limited to lesions identifiable on CT. Radiolabel uptake in prominent lesions was measured as maximum single-voxel standardized uptake value (SUVmax). Results Liver uptake of 64Cu was reduced approximately 75% with the 45 mg trastuzumab pre-dose, without significant effect on tumor uptake. The study included 89 CT-positive lesions; detection sensitivity was 77, 89 and 93% for Day 1, Day 2 and 18F-FDG, respectively. On average, tumor uptake was similar for 64Cu-DOTA-trastuzumab and 18F-FDG [SUVmax (mean, range): Day 1 (8.1, 3.0-22.5, n=48); Day 2 (8.9, 0.9-28.9, n=38); 18F-FDG (9.7, 3.3-25.4, n=56)], but the extent of same-lesion uptake was not

  18. Combination of two anti-CD5 monoclonal antibodies synergistically induces complement-dependent cytotoxicity of chronic lymphocytic leukaemia cells.

    PubMed

    Klitgaard, Josephine L; Koefoed, Klaus; Geisler, Christian; Gadeberg, Ole V; Frank, David A; Petersen, Jørgen; Jurlander, Jesper; Pedersen, Mikkel W

    2013-10-01

    The treatment of chronic lymphocytic leukaemia (CLL) has been improved by introduction of monoclonal antibodies (mAbs) that exert their effect through secondary effector mechanisms. CLL cells are characterized by expression of CD5 and CD23 along with CD19 and CD20, hence anti-CD5 Abs that engage secondary effector functions represent an attractive opportunity for CLL treatment. Here, a repertoire of mAbs against human CD5 was generated and tested for ability to induce complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC) both as single mAbs and combinations of two mAbs against non-overlapping epitopes on human CD5. The results demonstrated that combinations of two mAbs significantly increased the level of CDC compared to the single mAbs, while no enhancement of ADCC was seen with anti-CD5 mAb combinations. High levels of CDC and ADCC correlated with low levels of Ab-induced CD5 internalization and degradation. Importantly, an anti-CD5 mAb combination enhanced CDC of CLL cells when combined with the anti-CD20 mAbs rituximab and ofatumumab as well as with the anti-CD52 mAb alemtuzumab. These results suggest that an anti-CD5 mAb combination inducing CDC and ADCC may be effective alone, in combination with mAbs against other targets or combined with chemotherapy for CLL and other CD5-expressing haematological or lymphoid malignancies. © 2013 John Wiley & Sons Ltd.

  19. A Spectrum of Monoclonal Antibodies Reactive with Human Mammary Tumor Cells

    NASA Astrophysics Data System (ADS)

    Colcher, D.; Horan Hand, P.; Nuti, M.; Schlom, J.

    1981-05-01

    Splenic lymphocytes of mice, immunized with membrane-enriched fractions of metastatic human mammary carcinoma tissues, were fused with the NS-1 non-immunoglobulin-secreting murine myeloma cell line. This resulted in the generation of hybridoma cultures secreting immunoglobulins reactive in solid-phase radioimmunoassays with extracts of metastatic mammary carcinoma cells from involved livers, but not with extracts of apparently normal human liver. As a result of further screening of immunoglobulin reactivities and double cloning of cultures, 11 monoclonal antibodies were chosen that demonstrated reactivities with human mammary tumor cells and not with apparently normal human tissues. These monoclonal antibodies could be placed into at least five major groups on the basis of their differential binding to the surface of various live human mammary tumor cells in culture, to extracts of mammary tumor tissues, or to tissue sections of mammary tumor cells studied by the immunoperoxidase technique. Whereas a spectrum of reactivities to mammary tumors was observed with the 11 monoclonal antibodies, no reactivity was observed to apparently normal cells of the following human tissues: breast, lymph node, lung, skin, testis, kidney, thymus, bone marrow, spleen, uterus, thyroid, intestine, liver, bladder, tonsils, stomach, prostate, and salivary gland. Several of the antibodies also demonstrated a ``pancarcinoma'' reactivity, showing binding to selected non-breast carcinomas. None of the monoclonal antibodies showed binding to purified ferritin or carcinoembryonic antigen. Monoclonal antibodies of all five major groups, however, demonstrated binding to human metastatic mammary carcinoma cells both in axillary lymph nodes and at distal sites.

  20. Breast cancer stem cells in HER2-negative breast cancer cells contribute to HER2-mediated radioresistance and molecular subtype conversion: clinical implications for serum HER2 in recurrent HER2-negative breast cancer.

    PubMed

    Kim, Yun Gyoung; Yoon, Yi Na; Choi, Hyang Suk; Kim, Ji-Hyun; Seol, Hyesil; Lee, Jin Kyung; Seong, Min-Ki; Park, In Chul; Kim, Kwang Il; Kim, Hyun-Ah; Kim, Jae-Sung; Noh, Woo Chul

    2018-01-19

    Although it has been proposed that the beneficial effect of HER2-targeted therapy in HER2-negative breast cancer is associated with the molecular subtype conversion, the underlying mechanism and the clinical biomarkers are unclear. Our study showed that breast cancer stem cells (BCSCs) mediated HER2 subtype conversion and radioresistance in HER2-negative breast cancer cells and evaluated serum HER2 as a clinical biomarker for HER2 subtype conversion. We found that the CD44 + /CD24 -/low BCSCs from HER2-negative breast cancer MCF7 cells overexpressed HER2 and EGFR and showed the radioresistant phenotype. In addition, we showed that trastuzumab treatment sensitized the radioresistant phenotype of the CD44 + /CD24 -/low cells with decreased levels of HER2 and EGFR, which suggested that HER2-targeted therapy in HER2-negative breast cancer could be useful for targeting BCSCs that overexpress HER2/EGFR. Importantly, our clinical data showed that serial serum HER2 measurement synchronously reflected the disease relapse and the change in tumor burden in some patients who were initially diagnosed as HER2-negative breast cancer, which indicated that serum HER2 could be a clinical biomarker for the evaluation of HER2 subtype conversion in patients with recurrent HER2-negative breast cancer. Therefore, our data have provided in vitro and in vivo evidence for the molecular subtype conversion of HER2-negative breast cancer.

  1. New Agents for Taxol-Resistant Breast Adenocarcinoma

    DTIC Science & Technology

    2004-07-01

    mg/ mi2 (14) using 3 hr infusion schedules failed to demonstrate marked improvement in disease response or survival, despite incurring severe sensory...analyzed immediately by flow cytometry. Immunoblotting The anti-human HER-2/neu mouse monoclonal antibody , clone 3B5, isotype IgGI, was obtained from...carboxyl domain of the human c-neu gene product. An affinity-purified sheep anti-mouse IgG whole antibody preparation conjugated to horseradish peroxidase

  2. Generation and functional analysis of monoclonal antibodies against the second extracellular loop of human M3 muscarinic acetylcholine receptor.

    PubMed

    Tsuboi, Hiroto; Nakamura, Yumi; Iizuka, Mana; Matsuo, Naomi; Matsumoto, Isao; Sumida, Takayuki

    2012-04-01

    The M3 muscarinic acetylcholine receptor (M3R) plays a crucial role in the activation of salivary and lachrymal glands. The M3R contains four extracellular domains (the N-terminal, and the first, second, and third extracellular loops), and we recently detected antibodies against each of these four domains in a subgroup of patients with Sjögren's syndrome (SS). Functional analysis indicated that the influence of such anti-M3R antibodies on salivary secretion might differ based on the epitopes to which they bind. To clarify the relationship between B-cell epitopes on the M3R and its function, we generated two hybridomas producing anti-M3R monoclonal antibodies against the second extracellular loop of M3R (anti-M3R(2nd) mAbs) and analyzed their function by Ca(2+)-influx assays, using a human salivary gland (HSG) cell line. These two anti-M3R(2nd) mAbs suppressed Ca(2+)-influx in the HSG cells induced by cevimeline stimulation, suggesting that autoantibodies against the second extracellular loop of M3R could be involved in salivary dysfunction in patients with SS.

  3. Engineering multivalent antibodies to target heregulin-induced HER3 signaling in breast cancer cells

    PubMed Central

    Kang, Jeffrey C; Poovassery, Jayakumar S; Bansal, Pankaj; You, Sungyong; Manjarres, Isabel M; Ober, Raimund J; Ward, E Sally

    2014-01-01

    The use of antibodies in therapy and diagnosis has undergone an unprecedented expansion during the past two decades. This is due in part to innovations in antibody engineering that now offer opportunities for the production of “second generation” antibodies with multiple specificities or altered valencies. The targeting of individual components of the human epidermal growth factor receptor (HER)3-PI3K signaling axis, including the preferred heterodimerization partner HER2, is known to have limited anti-tumor effects. The efficacy of antibodies or small molecule tyrosine kinase inhibitors (TKIs) in targeting this axis is further reduced by the presence of the HER3 ligand, heregulin. To address these shortcomings, we performed a comparative analysis of two distinct approaches toward reducing the proliferation and signaling in HER2 overexpressing tumor cells in the presence of heregulin. These strategies both involve the use of engineered antibodies in combination with the epidermal growth factor receptor (EGFR)/HER2 specific TKI, lapatinib. In the first approach, we generated a bispecific anti-HER2/HER3 antibody that, in the presence of lapatinib, is designed to sequester HER3 into inactive HER2-HER3 dimers that restrain HER3 interactions with other possible dimerization partners. The second approach involves the use of a tetravalent anti-HER3 antibody with the goal of inducing efficient HER3 internalization and degradation. In combination with lapatinib, we demonstrate that although the multivalent HER3 antibody is more effective than its bivalent counterpart in reducing heregulin-mediated signaling and growth, the bispecific HER2/HER3 antibody has increased inhibitory activity. Collectively, these observations provide support for the therapeutic use of bispecifics in combination with TKIs to recruit HER3 into complexes that are functionally inert. PMID:24492289

  4. Complete response in HER2+ leptomeningeal carcinomatosis from breast cancer with intrathecal trastuzumab.

    PubMed

    Oliveira, Mafalda; Braga, Sofia; Passos-Coelho, José Luís; Fonseca, Ricardo; Oliveira, João

    2011-06-01

    Trastuzumab, a monoclonal antibody against the HER2 receptor, is a major breakthrough in the treatment of HER2+ breast cancer. However, its high molecular weight precludes it from crossing the intact blood-brain barrier, making the central nervous system a sanctuary to HER2+ breast cancer metastases. We prospectively assessed functional outcome and toxicity of administering trastuzumab directly into the cerebrospinal fluid of a patient with leptomeningeal carcinomatosis (LC) and brain metastases from HER2+ breast cancer that had already been treated with other intrathecal chemotherapy, with no benefit. Upon signed informed consent, weekly lumbar puncture with administration of trastuzumab 25 mg was begun to a 44 year-old women with metastatic breast cancer (lymph node, bone, lung, and liver involvement) previously treated with tamoxifen, letrozole, anthracyclines, taxanes, capecitabine, intravenous trastuzumab, and lapatinib. She received 67 weekly administrations of intrathecal trastuzumab with marked clinical improvement and no adverse events. She survived 27 months after LC diagnosis. A complete leptomeningeal response, with no evidence of leptomeningeal metastasis at necropsy, was achieved. We believe that intrathecal trastuzumab administration should be prospectively evaluated to confirm clinical activity and optimize dose, schedule, and duration of treatment.

  5. Systemic therapy for HER2-positive early-stage breast cancer.

    PubMed

    Mathew, Aju; Romond, Edward H

    The advent of the targeted monoclonal antbody trastuzumab for treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer marked a revolution in the understanding and management of mammary carcinoma and, in practice, separated this subtype from other kinds of primary breast malignancy. Long term follow-up from the initial large adjuvant trials continue to show remarkably positive results. Currently, at least four additional agents targeting this receptor, using different and complementary mechanisms of action compared with trastuzumab, have been incorporated into clinical trials. The small molecule tyrosine kinase inhibitors lapatinib and neratinib, in addition to the antibody pertuzumab and the antibody-drug conjugate trastuzumab-ematansine, have shown efficacy in metastatic breast cancer and are being evaluated both in neoadjuvant and adjuvant trials for early stage disease. The cytotoxic chemotherapy regimens used in combination with these agents also are evolving and different therapeutic approaches are emerging for patients depending on their relative level of risk from their cancers, thus moving clinical management toward individualized therapy. Much has been learned about managing the toxicities of treatment and pre-operative approaches have provided a means of assessing the sensitivity of individual patients' cancers to specific treatment regimens. This review traces the development of these studies and focuses on improvements in adjuvant and neoadjuvant therapy for patients with HER2-positive disease whose prognosis has changed in the last decade from dire to favorable. A path forward has been set by which the goal of cure is attainable for almost all patients faced with this aggressive form of breast cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. HER2-targeted recombinant protein immuno-caspase-6 effectively induces apoptosis in HER2-overexpressing GBM cells in vitro and in vivo.

    PubMed

    Zhang, Leiming; Ren, Junlin; Zhang, Hangyu; Cheng, Gang; Xu, Yanming; Yang, Shuangwu; Dong, Chao; Fang, Dandong; Zhang, Jianning; Yang, Angang

    2016-11-01

    Glioblastoma multiforme (GBM), which is associated with a high rate of morbidity and mortality, is among the most malignant and treatment-refractory neoplasms in human adults. As GBM is highly resistant to conventional therapies, immunotherapies are a promising treatment candidate. HER2 is an attractive target for GBM immunotherapy, as its expression is highly associated with various types of GBM. We previously reported that a novel HER2-targeted recombinant protein e23sFv-Fdt-casp6 has an antitumor effect on HER2-positive gastric cancer cells. In this study, we established a genetically modified Chinese hamster ovary cell line, which produced and secreted e23sFv-Fdt-casp6 proteins. Following specific binding to and internalization into HER2-overexpressing tumor cells, the e23sFv-Fdt-casp6 protein induced tumor cell apoptosis and inhibited the proliferation of HER2-overexpressing A172 and U251MG cells in vitro, but not in U87MG cells with undetectable HER2. The e23sFv-Fdt-casp6 gene was introduced into severe combined immunodeficient mice bearing human glioblastoma xenografts by using intramuscular injections of a liposome-encapsulated vector. The recombinant protein e23sFv-Fdt-casp6 specifically targeted tumor cells and induced apoptosis, thereby leading to potent inhibition of tumor growth and prolonged the survival time of tumor-bearing mice. We concluded that e23sFv‑Fdt‑casp6 represents a promising HER2-targeted treatment option for human gliomas.

  7. Enhancement of the p27Kip1-mediated antiproliferative effect of trastuzumab (Herceptin) on HER2-overexpressing tumor cells.

    PubMed

    Marches, Radu; Uhr, Jonathan W

    2004-11-10

    The oncogenic activity of the overexpressed HER2 tyrosine kinase receptor requires its localization in the plasma membrane. The antitumor effect of anti-HER2 antibodies (Abs) is mainly dependent on receptor downregulation and comprises p27Kip1-mediated G1 cell cycle arrest. However, one major limitation of anti-HER2 therapy is the reversibility of tumor growth inhibition after discontinuation of treatment caused by the mitogenic signaling associated with cell surface receptor re-expression. We found that the level of p27Kip1 upregulation, inhibition of Cdk2 activity and magnitude of G1 arrest induced by the humanized Ab trastuzumab (Herceptin, HCT) on BT474 and SKBr3 HER2-overexpressing breast cancer cells correlates with the level of cell surface receptor. Thus, continuous exposure of cells to HCT for 72 hr results in downregulation of the cell surface receptor and a concurrent increase in the level of p27Kip1 protein. Discontinuation of Ab exposure after the first 8 hr results in failure to upregulate p27Kip1 and arrest of cell cycle progression. We show that the lysosomotropic amine chloroquine (CQ) augments receptor internalization in HER2-overexpressing cells either pretreated or continuously treated with HCT and leads to an increased and sustained inhibitory effect. The enhanced CQ-dependent loss of functional HER2 from the cell surface resulted in sustained inactivation of the serine/threonine kinase Akt, upregulation of p27Kip1 protein and inhibition of cyclin E/Cdk2 activity. Potentiation of the inhibitory effect of HCT by CQ was directly related to loss of HER2 from the plasma membrane since prevention of Ab-mediated receptor endocytosis by engagement of the receptor with immobilized HCT abrogated the effect of CQ.

  8. Monitoring of antigen-specific CD8 T cells in patients with type 1 diabetes treated with antiCD3 monoclonal antibodies.

    PubMed

    Cernea, Simona; Herold, Kevan C

    2010-02-01

    The way in which anti-CD3 monoclonal antibodies (mAbs) modify human immune responses in type 1 diabetes (T1DM) is not known. We prepared a panel of Class I HLA-A2.1 tetramers with peptides from diabetes-associated antigens and studied the frequency and phenotype of the cells in patients with T1DM and blood donors and in patients treated with anti-CD3 mAb (Teplizumab). More patients with T1DM showed positive staining for at least 1 tetramer using frozen and fresh samples (p<0.05). Three months following treatment with anti-CD3 mAb, the proportion of GAD65- and InsB-peptide reactive CD8+ T cells increased (p<0.05). The phenotype of these cells was modulated from naïve to effector memoryRA+. We concludethat Class I MHC tetramers can identify antigen specific CD8+ T cells in patients with T1DM. The frequency of certain specificities increases after treatment with anti-CD3 mAb. Their modulated phenotype may have functional consequences for their pathogenicity. Copyright 2009 Elsevier Inc. All rights reserved.

  9. Lipopolysaccharide-Specific but Not Anti-Flagellar Immunoglobulin A Monoclonal Antibodies Prevent Salmonella enterica Serotype Enteritidis Invasion and Replication within HEp-2 Cell Monolayers

    PubMed Central

    Iankov, Ianko D.; Petrov, Dragomir P.; Mladenov, Ivan V.; Haralambieva, Iana H.; Mitov, Ivan G.

    2002-01-01

    The protective potential of immunoglobulin A (IgA) monoclonal antibodies (MAbs) directed against O and H antigens of Salmonella enterica serotype Enteritidis to prevent bacterial adhesion to and invasion of HEp-2 cells was evaluated. Although anti-flagellar IgA MAbs showed strong agglutinating capacities, they did not protect cell monolayers. In contrast, IgA MAbs specific for the O:9 epitope of Salmonella lipopolysaccharide antigen alone prevented S. enterica serotype Enteritidis entry and replication within HEp-2 cells, and the protection was not mediated by direct binding of antibodies to bacterial adhesins or by agglutination of microorganisms. PMID:11854252

  10. A novel anti-GPC3 monoclonal antibody (YP7) | Center for Cancer Research

    Cancer.gov

    Glypican-3 (GPC3) is an emerging therapeutic target in hepatoma. A novel anti-GPC3 monoclonal antibody (YP7) has been generated through a combination of peptide immunization and high-throughput flow cytometry screening. YP7 binds cell-surface-associated GPC3 with high affinity and exhibits significant hepatoma xenograft growth inhibition in nude mice. The new antibody may have

  11. Grb2-SH3 ligand inhibits the growth of HER2+ cancer cells and has antitumor effects in human cancer xenografts alone and in combination with docetaxel.

    PubMed

    Gril, Brunilde; Vidal, Michel; Assayag, Franck; Poupon, Marie-France; Liu, Wang-Qing; Garbay, Christiane

    2007-07-15

    HER2 represents an important signaling pathway in breast and other cancers. Herceptin has demonstrated clinical activity, but resistance is common. Thus, new therapeutic approaches to the HER2 pathway are needed. Grb2 is an adaptor protein involved in Ras-dependent signaling induced by HER2 receptors. A specific Grb2-SH3 ligand, designed and synthesized in our laboratory, called peptidimer-c, inhibited colony formation in HER2 overexpressing SKBr3 cancer cells. Combined treatment of peptidimer-c with docetaxel further inhibited both colony formation and tumor cell survival compared to docetaxel treatment alone. Efficacy of this combined treatment was correlated with a reduction in the phosphorylation of MAPK and AKT. Finally, peptidimer-c reduced the growth of a HER2(+) human breast cancer (BK111) xenograft in nude mice and potentiated the antitumor effect of docetaxel in a HER2+ hormone-independent human prostate adenocarcinoma (PAC120 HID28) xenograft. These results validate Grb2 as a new target for the HER2 pathway. (c) 2007 Wiley-Liss, Inc.

  12. SU-E-I-81: Targeting of HER2-Expressing Tumors with Dual PET-MR Imaging Probes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xu, P; Peng, Y; Sun, M

    2015-06-15

    Purpose: The detection of human epidermal growth factor receptor type 2 (HER2) expression in malignant tumors provides important information influencing patient management. Radionuclide in vivo imaging of HER2 may permit the detection of HER2 in both primary tumors and metastases by a single noninvasive procedure. Trastuzumab, effective in about 15 % of women with breast cancer, downregulates signalling through the Akt/PI3K and MAPK pathways.These pathways modulate metabolism which can be monitored by positron emission tomography (PET) and magnetic resonance imaging (MRI). Methods: The relationship between response of HER2 overexpressing tumours and changes in imaging PET or SPECT and MRI willmore » be examined by a integrated bimodal imaging probe.Small (7 kDa) high-affinity anti-HER2 Affibody molecules and KCCYSL targeting peptide may be suitable tracers for visualization of HER2-expressing tumors. Peptide-conjugated iron oxide nanoparticles (Fe3O4 NPs) as MRI imaging and CB-TE2A as PET imaging are integrated into a single synthetic molecule in the HER2 positive cancer. Results: One of targeted contrast bimodal imaging probe agents was synthesized and evaluated to target HER2-expressing tumors in a HER2 positive rat model. We will report the newest results regarding the development of bimodal imaging probes. Conclusion: The preliminary results of the bimodal imaging probe presents high correlation of MRI signal and PET imaging intensity in vivo. This unique feature can hardly be obtained by single model contrast agents. It is envisioned that this bimodal agents can hold great potential for accurate detection of HER2-expressing tumors which are critical for clinical management of the disease.« less

  13. The role of MAPK signaling pathway in the Her-2-positive meningiomas

    PubMed Central

    Wang, Zhaoyin; Wang, Weijia; Xu, Shan; Wang, Shanshan; Tu, Yi; Xiong, Yifeng; Mei, Jinhong; Wang, Chunliang

    2016-01-01

    Meningiomas are common types of adult nerve system tumors. Although most cases are considered benign, due to its high rate of recurrence and easy malignant progression to anaplastic meningioma they present a puzzle for the current treatment. The HER-2 oncogene has important value for meningioma cells development and progression. So far, little is known about the effect on the exact underlying signal pathway and molecular mechanisms of HER-2-positive meningioma cells. The goal of the present study was to determine the effects of HER-2 gene and possible involvement of MAPK signal pathway in human malignant meningioma. We applied q-PCR analysis, immunofluorescence (IF) staining, western blot analysis, animal model, MAPK inhibition, MTT assay and cell invasion analysis for the investigation. The results demonstrated that the downregulation of the expression of HER-2 significantly inhibited cell motility and proliferation of human meningioma cells in vivo. Accordingly, in the HER-2-overexpression meningioma cells with the inhibition of ERK1/2, ERK5, JNK, in the cells with the ERK1/2, ERK5 inhibition, protein expression was markedly suppressed as well as the cell proliferation resistance. No difference was observed in the HER-2-overexpression meningioma cells with the inhibition of JNK. These findings suggest that HER-2 gene can affect the proliferation ability of human meningioma cells in vivo and MAPK signal pathway may contribute to the carcinogenesis and development of human meningiomas combinating with HER-2. PMID:27279438

  14. Inhibition of anti-CD3 monoclonal antibody-induced T-cell proliferation and interleukin-2 secretion by physiologic combinations of dexamethasone and prostaglandin E2.

    PubMed

    Elliott, L; Brooks, W; Roszman, T

    1993-12-01

    1. The purpose of these studies was to characterize further previous observations from our laboratory indicating that physiologic concentrations of dexamethasone (DEX) and prostaglandin E2 (PGE2) added together result in synergistic inhibition of the proliferative response of T cells stimulated via the T-cell receptor CD3 signaling complex (TCR/CD3). 2. Various physiologic concentrations of DEX and PGE2 were added to T cells stimulated with immobilized anti-CD3 monoclonal antibody (mAb) and cultured at optimal and suboptimal cell densities. The results demonstrate that the proliferative response of anti-CD3 mAb-stimulated T cells cultured at a suboptimal cell density is more suppressed than that of T cells cultured at optimal concentrations. 3. The proliferative response of CD4+ T cells to immobilized anti-CD3 mAb was also determined in the presence of PGE2 and DEX. The data indicate that the CD4+ subset of T cells is more sensitive to the synergistic antiproliferative effects of DEX and PGE2 compared to whole T-cell populations. 4. Various concentrations of DEX and/or PGE2 were added to T cells stimulated with anti-CD3 mAb and the secretion of interleukin-2 (IL-2) was determined. The results demonstrate that concentrations of DEX and PGE2 which individually do not significantly suppress IL-2 synthesis act together to inhibit the synthesis of IL-2 synergistically. 5. The addition of an exogenous source of recombinant IL-2 (rIL-2) to T cells stimulated in the presence of DEX and PGE2 completely reversed the synergistic antiproliferative effect of these two compounds. This reversal was even more pronounced with T cells cultured at a suboptimal cell density. Additionally, PGE2 and DEX did not affect expression of the IL-2 receptor (IL-2R), as measured by upregulation of the alpha chain, on anti-CD3 mAb stimulated T cells. 6. Collectively these data indicate that physiologic concentrations of PGE2 and DEX, which alone have no effect on anti-CD3 mAb-induced T

  15. Increased Expression of HER2, HER3, and HER2:HER3 Heterodimers in HPV-Positive HNSCC Using a Novel Proximity-Based Assay: Implications for Targeted Therapies.

    PubMed

    Pollock, Netanya I; Wang, Lin; Wallweber, Gerald; Gooding, William E; Huang, Weidong; Chenna, Ahmed; Winslow, John; Sen, Malabika; DeGrave, Kara A; Li, Hua; Zeng, Yan; Grandis, Jennifer R

    2015-10-15

    In other cancer types, HPV infection has been reported to coincide with overexpression of HER2 (ERBB2) and HER3 (ERBB3); however, the association between HER2 or HER3 expression and dimer formation in HNSCC has not been reported. Overexpression of HER2 and HER3 may contribute to resistance to EGFR inhibitors, including cetuximab, although the contribution of HPV in modulating cetuximab response remains unknown. Determination of heterodimerization of HER receptors is challenging and has not been reported in HNSCC. The present study aimed to determine the expression of HER proteins in HPV(+) versus HPV(-) HNSCC tumors using a proximity-based protein expression assay (VeraTag), and to determine the efficacy of HER-targeting agents in HPV(+) and HPV(-) HNSCC cell lines. Expression of total HER1, HER2, and HER3, p95HER2, p-HER3, HER1:HER1 homodimers, HER2:HER3 heterodimers, and the HER3-PI3K complex in 88 HNSCC was determined using VeraTag, including 33 baseline tumors from individuals treated in a trial including cetuximab. Inhibition of cell growth and protein activation with cetuximab and afatinib was compared in HPV(+) and HPV(-) cetuximab-resistant cell lines. Expression of total HER2, total HER3, HER2:HER3 heterodimers, and the HER3:PI3K complex were significantly elevated in HPV(+) HNSCC. Total EGFR was significantly increased in HPV(-) HNSCC where VeraTag assay results correlated with IHC. Afatinib significantly inhibited cell growth when compared with cetuximab in the HPV(+) and HPV(-) cetuximab-resistant HNSCC cell lines. These findings suggest that agents targeting multiple HER proteins may be effective in the setting of HPV(+) HNSCC and/or cetuximab resistance. ©2015 American Association for Cancer Research.

  16. DS-8201a, a new HER2-targeting antibody-drug conjugate incorporating a novel DNA topoisomerase I inhibitor, overcomes HER2-positive gastric cancer T-DM1 resistance.

    PubMed

    Takegawa, Naoki; Nonagase, Yoshikane; Yonesaka, Kimio; Sakai, Kazuko; Maenishi, Osamu; Ogitani, Yusuke; Tamura, Takao; Nishio, Kazuto; Nakagawa, Kazuhiko; Tsurutani, Junji

    2017-10-15

    Anti-HER2 therapies are beneficial for patients with HER2-positive breast or gastric cancer. T-DM1 is a HER2-targeting antibody-drug conjugate (ADC) comprising the antibody trastuzumab, a linker, and the tubulin inhibitor DM1. Although effective in treating advanced breast cancer, all patients eventually develop T-DM1 resistance. DS-8201a is a new ADC incorporating an anti-HER2 antibody, a newly developed, enzymatically cleavable peptide linker, and a novel, potent, exatecan-derivative topoisomerase I inhibitor (DXd). DS-8201a has a drug-to-antibody-ratio (DAR) of 8, which is higher than that of T-DM1 (3.5). Owing to these unique characteristics and unlike T-DM1, DS-8201a is effective against cancers with low-HER2 expression. In the present work, T-DM1-resistant cells (N87-TDMR), established using the HER2-positive gastric cancer line NCI-N87 and continuous T-DM1 exposure, were shown to be susceptible to DS-8201a. The ATP-binding cassette (ABC) transporters ABCC2 and ABCG2 were upregulated in N87-TDMR cells, but HER2 overexpression was retained. Furthermore, inhibition of ABCC2 and ABCG2 by MK571 restored T-DM1 sensitivity. Therefore, resistance to T-DM1 is caused by efflux of its payload DM1, due to aberrant expression of ABC transporters. In contrast to DM1, DXd payload of DS-8201a inhibited the growth of N87-TDMR cells in vitro. This suggests that either DXd may be a poor substrate of ABCC2 and ABCG2 in comparison to DM1, or the high DAR of DS-8201a relative to T-DM1 compensates for increased efflux. Notably, N87-TDMR xenograft tumor growth was prevented by DS-8201a. In conclusion, the efficacy of DS-8201a as a treatment for patients with T-DM1-resistant breast or gastric cancer merits investigation. © 2017 UICC.

  17. C-Cbl reverses HER2-mediated tamoxifen resistance in human breast cancer cells.

    PubMed

    Li, Wei; Xu, Ling; Che, Xiaofang; Li, Haizhou; Zhang, Ye; Song, Na; Wen, Ti; Hou, Kezuo; Yang, Yi; Zhou, Lu; Xin, Xing; Xu, Lu; Zeng, Xue; Shi, Sha; Liu, Yunpeng; Qu, Xiujuan; Teng, Yuee

    2018-05-02

    Tamoxifen is a frontline therapy for estrogen receptor (ER)-positive breast cancer in premenopausal women. However, many patients develop resistance to tamoxifen, and the mechanism underlying tamoxifen resistance is not well understood. Here we examined whether ER-c-Src-HER2 complex formation is involved in tamoxifen resistance. MTT and colony formation assays were used to measure cell viability and proliferation. Western blot was used to detect protein expression and protein complex formations were detected by immunoprecipitation and immunofluorescence. SiRNA was used to examine the function of HER2 in of BT474 cells. An in vivo xenograft animal model was established to examine the role of c-Cbl in tumor growth. MTT and colony formation assay showed that BT474 cells are resistant to tamoxifen and T47D cells are sensitive to tamoxifen. Immunoprecipitation experiments revealed ER-c-Src-HER2 complex formation in BT474 cells but not in T47D cells. However, ER-c-Src-HER2 complex formation was detected after overexpressing HER2 in T47D cells and these cells were more resistant to tamoxifen. HER2 knockdown by siRNA in BT474 cells reduced ER-c-Src-HER2 complex formation and reversed tamoxifen resistance. ER-c-Src-HER2 complex formation was also disrupted and tamoxifen resistance was reversed in BT474 cells by the c-Src inhibitor PP2 and HER2 antibody trastuzumab. Nystatin, a lipid raft inhibitor, reduced ER-c-Src-HER2 complex formation and partially reversed tamoxifen resistance. ER-c-Src-HER2 complex formation was disrupted by overexpression of c-Cbl but not by the c-Cbl ubiquitin ligase mutant. In addition, c-Cbl could reverse tamoxifen resistance in BT474 cells, but the ubiquitin ligase mutant had no effect. The effect of c-Cbl was validated in BT474 tumor-bearing nude mice in vivo. Immunofluorescence also revealed ER-c-Src-HER2 complex formation was reduced in tumor tissues of nude mice with c-Cbl overexpression. Our results suggested that c-Cbl can reverse tamoxifen

  18. Recombinant nanocomposites by the clinical drugs of Abraxane® and Herceptin® as sequentially dual-targeting therapeutics for breast cancer.

    PubMed

    Ding, Shuang; Xiong, Jian; Lei, Dan; Zhu, Xiao-Li; Zhang, Hai-Jun

    2018-01-01

    Breast cancer greatly threatens the health of women all over the word despite of several effective drugs. Targeted therapy for breast cancer is limited to human epidermal growth factor receptor 2 (HER2). Herceptin ® , monoclonal antibody against HER2, is now widely used in HER2(+) breast cancer. Abraxane ® , the current gold standard for paclitaxel (PTX) delivery, has shown superiority in breast cancer based on nanoparticle albumin bound technology. Despite these advances, further novel targeted therapy with more improved anti-tumor efficacy for breast cancer is still urgently needed. Here, we report the recombinant nanocomposites (NPs) composed of the above two clinical drugs of Abraxane ® and Herceptin ® (Abra/anti-HER2), which at first migrates to the tumor region through the unique targeting mechanism of human serum albumin (HSA) of Abraxane ® , and sequentially further precisely recognize the HER2(+) breast cancer cells due to Herceptin ® . The Abra/anti-HER2 NPs were fabricated by a "one-step" synthesis using EDC/NHS. In vitro analysis of cell viability, apoptosis and cell cycle revealed that Abra/anti-HER2 NPs showed more anti-tumor efficacy against HER2(+) SK-BR-3 cells than Abraxane ® at equivalent PTX concentration. In addition, in HER2(+) breast cancer xenograft model, Abra/anti-HER2 NPs significantly inhibited tumor growth with less side effects. Moreover, the properties of more precise target and delayed release of PTX were proved by NIRF imaging. Thus, our results indicate that Abra/anti-HER2 NPs could represent a next-generation sequentially dual-targeting therapeutic agent for HER2(+) breast cancer.

  19. Collagen Sponge Functionalized with Chimeric Anti-BMP-2 Monoclonal Antibody Mediates Repair of Critical-Size Mandibular Continuity Defects in a Nonhuman Primate Model

    PubMed Central

    Xie, Yilin; Su, Yingying; Tang, Jianxia; Goh, Bee Tin; Saigo, Leonardo; Zhang, Chunmei; Wang, Jinsong; Khojasteh, Arash; Wang, Songlin

    2017-01-01

    Antibody-mediated osseous regeneration (AMOR) has been introduced by our research group as a tissue engineering approach to capture of endogenous growth factors through the application of specific monoclonal antibodies (mAbs) immobilized on a scaffold. Specifically, anti-Bone Morphogenetic Protein- (BMP-) 2 mAbs have been demonstrated to be efficacious in mediating bone repair in a number of bone defects. The present study sought to investigate the application of AMOR for repair of mandibular continuity defect in nonhuman primates. Critical-sized mandibular continuity defects were created in Macaca fascicularis locally implanted with absorbable collagen sponges (ACS) functionalized with chimeric anti-BMP-2 mAb or isotype control mAb. 2D and 3D analysis of cone beam computed tomography (CBCT) imaging demonstrated increased bone density and volume observed within mandibular continuity defects implanted with collagen scaffolds functionalized with anti-BMP-2 mAb, compared with isotype-matched control mAb. Both CBCT imaging and histologic examination demonstrated de novo bone formation that was in direct apposition to the margins of the resected bone. It is hypothesized that bone injury may be necessary for AMOR. This is evidenced by de novo bone formation adjacent to resected bone margins, which may be the source of endogenous BMPs captured by anti-BMP-2 mAb, in turn mediating bone repair. PMID:28401163

  20. Quantitative HER2 and p95HER2 levels in primary breast cancers and matched brain metastases.

    PubMed

    Duchnowska, Renata; Sperinde, Jeff; Chenna, Ahmed; Huang, Weidong; Weidler, Jodi M; Winslow, John; Haddad, Mojgan; Paquet, Agnes; Lie, Yolanda; Trojanowski, Tomasz; Mandat, Tomasz; Kowalczyk, Anna; Czartoryska-Arłukowicz, Bogumiła; Radecka, Barbara; Jarosz, Bożena; Staszkiewicz, Rafal; Kalinka-Warzocha, Ewa; Chudzik, Małgorzata; Biernat, Wojciech; Jassem, Jacek

    2015-09-01

    Patients with advanced breast cancer positive for human epidermal growth factor receptor 2 (HER2) are at high risk for brain metastasis (BM). The prevalence and significance of expression of HER2 and its truncated form p95HER2 (p95) in BM is unknown. Seventy-five pairs of formalin-fixed paraffin-embedded samples from matched primary breast cancers (PBCs) and BM were assayed for quantitative p95 and HER2-total (H2T) protein expression using the p95 VeraTag and HERmark assays, respectively. There was a net increase in p95 and H2T expression in BM relative to the matched PBC (median 1.5-fold, P = .0007 and 2.1-fold, P < .0001, respectively). Cases with H2T-positive tumors were more likely to have the largest (≥5-fold) increase in p95 (odds ratio = 6.3, P = .018). P95 positivity in PBC correlated with progression-free survival (hazard ratio [HR] = 2.2, P = .013), trended with shorter time to BM (HR = 1.8, P = .070), and correlated with overall survival (HR = 2.1, P = .042). P95 positivity in BM correlated with time to BM (HR = 2.0, P = .016) but did not correlate with overall survival from the time of BM diagnosis (HR = 1.2, P = .61). This is the first study of quantitative p95 and HER2 expression in matched PBC and BM. BM of breast cancer shows significant increases in expression of both biomarkers compared with matched PBC. These data provide a rationale for future correlative studies on p95 and HER2 levels in BM. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. HER-2 Pulsed Dendritic Cell Vaccine Can Eliminate HER-2 Expression and Impact DCIS

    PubMed Central

    Sharma, Anupama; Koldovsky, Ursula; Xu, Shuwen; Mick, Rosemarie; Roses, Robert; Fitzpatrick, Elizabeth; Weinstein, Susan; Nisenbaum, Harvey; Levine, Bruce L; Fox, Kevin; Zhang, Paul; Koski, Gary; Czerniecki, Brian J

    2011-01-01

    Background HER-2/neu over-expression plays a critical role in breast cancer development and its expression in ductal carcinoma in situ (DCIS) is associated with development of invasive breast cancer. A vaccine targeting HER-2/neu expression in DCIS may initiate immunity against invasive cancer. Methods A HER-2/neu dendritic cell (DC) vaccine was administered to 27 patients with HER-2/neu over-expressing DCIS. The HER-2/neu vaccine was administered prior to surgical resection and pre- and post-vaccination analysis was conducted to assess clinical results. Results At surgery, 5 of 27 (18.5%) vaccinated subjects had no evidence of remaining disease, while among 22 subjects with residual DCIS, HER-2/neu expression was eradicated in 11 (50%). When comparing ERneg with ERpos DCIS lesions, vaccination was more effective in hormone-independent DCIS. Following vaccination, no residual DCIS was found in 40% of ERneg subjects compared to 5.9% in ERpos subject. Sustained HER-2/neu expression was found in 10% of ERneg subjects compared to 47.1% in ERpos subjects (p=0.04). Post-vaccination phenotypes were significantly different between ERpos and ERneg subjects (p=0.01), with 7 of 16 (43.8%) initially presenting with ERpos HER-2/neupos Luminal B phenotype finishing with the ERpos HER-2/neuneg Luminal A phenotype, and 3 of 6 (50%) with the ERneg HER-2/neupos phenotype changing to the ERneg HER-2/neuneg phenotype. Conclusions Results suggest vaccination against HER-2/neu is safe, well-tolerated and induces decline and or eradication of HER-2/neu expression. These findings warrant further exploration of HER-2/neu vaccination in estrogen-independent breast cancer and highlight the need to target additional tumor associated antigens and pathways. PMID:22252842

  2. N-Acetylcysteine breaks resistance to trastuzumab caused by MUC4 overexpression in human HER2 positive BC-bearing nude mice monitored by 89Zr-Trastuzumab and 18F-FDG PET imaging

    PubMed Central

    Wimana, Zéna; Gebhart, Geraldine; Guiot, Thomas; Vanderlinden, Bruno; Larsimont, Denis; Doumont, Gilles; Van Simaeys, Gaetan; Goldman, Serge; Flamen, Patrick; Ghanem, Ghanem

    2017-01-01

    Trastuzumab remains an important drug in the management of human epidermal growth factor receptor 2 (HER2) overexpressing breast cancer (BC). Several studies reported resistance mechanisms to trastuzumab, including impaired HER2-accessibility caused by mucin 4 (MUC4). Previously, we demonstrated an increase of Zirconium-89-radiolabeled-trastuzumab (89Zr-Trastuzumab) accumulation when MUC4-overexpressing BC-cells were challenged with the mucolytic drug N-Acetylcysteine (NAC). Hereby, using the same approach we investigated whether tumor exposure to NAC would also enhance trastuzumab-efficacy. Dual SKBr3 (HER2+/MUC4-, sensitive to trastuzumab) and JIMT1 (HER2+/MUC4+, resistant to trastuzumab) HER2-BC-bearing-xenografts were treated with trastuzumab and NAC. Treatment was monitored by molecular imaging evaluating HER2-accessibility/activity (89Zr-Trastuzumab HER2-immunoPET) and glucose metabolism (18F-FDG-PET/CT), as well as tumor volume and the expression of key proteins. In the MUC4-positive JIMT1-tumors, the NAC-trastuzumab combination resulted in improved tumor-growth control compared to trastuzumab alone; with smaller tumor volume/weight, lower 18F-FDG uptake, lower %Ki67 and pAkt-expression. NAC reduced MUC4-expression, but did not affect HER2-expression or the trastuzumab-sensitivity of the MUC4-negative SKBr3-tumors. These findings suggest that improving HER2-accessibility by reducing MUC4-masking with the mucolytic drug NAC, results in a higher anti-tumor effect of trastuzumab. This provides a rationale for the potential benefit of this approach to possibly treat a subset of HER2-positive BC overexpressing MUC4. PMID:28915583

  3. N-Acetylcysteine breaks resistance to trastuzumab caused by MUC4 overexpression in human HER2 positive BC-bearing nude mice monitored by 89Zr-Trastuzumab and 18F-FDG PET imaging.

    PubMed

    Wimana, Zéna; Gebhart, Geraldine; Guiot, Thomas; Vanderlinden, Bruno; Larsimont, Denis; Doumont, Gilles; Van Simaeys, Gaetan; Goldman, Serge; Flamen, Patrick; Ghanem, Ghanem

    2017-08-22

    Trastuzumab remains an important drug in the management of human epidermal growth factor receptor 2 (HER2) overexpressing breast cancer (BC). Several studies reported resistance mechanisms to trastuzumab, including impaired HER2-accessibility caused by mucin 4 (MUC4). Previously, we demonstrated an increase of Zirconium-89-radiolabeled-trastuzumab ( 89 Zr-Trastuzumab) accumulation when MUC4-overexpressing BC-cells were challenged with the mucolytic drug N-Acetylcysteine (NAC). Hereby, using the same approach we investigated whether tumor exposure to NAC would also enhance trastuzumab-efficacy. Dual SKBr3 (HER2+/MUC4-, sensitive to trastuzumab) and JIMT1 (HER2+/MUC4+, resistant to trastuzumab) HER2-BC-bearing-xenografts were treated with trastuzumab and NAC. Treatment was monitored by molecular imaging evaluating HER2-accessibility/activity ( 89 Zr-Trastuzumab HER2-immunoPET) and glucose metabolism ( 18 F-FDG-PET/CT), as well as tumor volume and the expression of key proteins. In the MUC4-positive JIMT1-tumors, the NAC-trastuzumab combination resulted in improved tumor-growth control compared to trastuzumab alone; with smaller tumor volume/weight, lower 18F-FDG uptake, lower %Ki67 and pAkt-expression. NAC reduced MUC4-expression, but did not affect HER2-expression or the trastuzumab-sensitivity of the MUC4-negative SKBr3-tumors. These findings suggest that improving HER2-accessibility by reducing MUC4-masking with the mucolytic drug NAC, results in a higher anti-tumor effect of trastuzumab. This provides a rationale for the potential benefit of this approach to possibly treat a subset of HER2-positive BC overexpressing MUC4.

  4. Molecular assays in detecting EGFR gene aberrations: an updated HER2-dependent algorithm for interpreting gene signals; a short technical report.

    PubMed

    Tsiambas, Evangelos; Ragos, Vasileios; Lefas, Alicia Y; Georgiannos, Stavros N; Rigopoulos, Dimitrios N; Georgakopoulos, Georgios; Stamatelopoulos, Athanasios; Grapsa, Dimitra; Syrigos, Konstantinos

    2016-01-01

    Purpose: Among oncogenes that have already been identified and cloned, Epidermal Growth Factor Receptor (EGFR) remains one of the most significant. Understanding its deregulation mechanisms improves critically patients' selection for personalized therapies based on modern molecular biology and oncology guidelines. Anti-EGFR targeted therapeutic strategies have been developed based on specific genetic profiles and applied in subgroups of patients suffering by solid cancers of different histogenetic origin. Detection of specific EGFR somatic mutations leads to tyrosine kinase inhibitors (TKIs) application in subsets of them. Concerning EGFR gene numerical imbalances, identification of pure gene amplification is critical for targeting the molecule via monoclonal antibodies (mAbs). In the current technical paper we demonstrate the main molecular methods applied in EGFR analyses focused also on new data in interpreting numerical imbalances based on ASCO/ACAP guidelines for HER2 in situ hybridization (ISH) clarifications.

  5. A gene expression signature of Retinoblastoma loss-of-function predicts resistance to neoadjuvant chemotherapy in ER-positive/HER2-positive breast cancer patients.

    PubMed

    Risi, Emanuela; Grilli, Andrea; Migliaccio, Ilenia; Biagioni, Chiara; McCartney, Amelia; Guarducci, Cristina; Bonechi, Martina; Benelli, Matteo; Vitale, Stefania; Biganzoli, Laura; Bicciato, Silvio; Di Leo, Angelo; Malorni, Luca

    2018-07-01

    HER2-positive (HER2+) breast cancers show heterogeneous response to chemotherapy, with the ER-positive (ER+) subgroup deriving less benefit. Loss of retinoblastoma tumor suppressor gene (RB1) function has been suggested as a cardinal feature of breast cancers that are more sensitive to chemotherapy and conversely resistant to CDK4/6 inhibitors. We performed a retrospective analysis exploring RBsig, a gene signature of RB loss, as a potential predictive marker of response to neoadjuvant chemotherapy in ER+/HER2+ breast cancer patients. We selected clinical trials of neoadjuvant chemotherapy ± anti-HER2 therapy in HER2+ breast cancer patients with available information on gene expression data, hormone receptor status, and pathological complete response (pCR) rates. RBsig expression was computed in silico and correlated with pCR. Ten studies fulfilled the inclusion criteria and were included in the analysis (514 patients). Overall, of 211 ER+/HER2+ breast cancer patients, 49 achieved pCR (23%). The pCR rate following chemotherapy ± anti-HER2 drugs in patients with RBsig low expression was significantly lower compared to patients with RBsig high expression (16% vs. 30%, respectively; Fisher's exact test p = 0.015). The area under the ROC curve (AUC) was 0.62 (p = 0.005). In the 303 ER-negative (ER-)/HER2+ patients treated with chemotherapy ± anti-HER2 drugs, the pCR rate was 43%. No correlation was found between RBsig expression and pCR rate in this group. Low expression of RBsig identifies a subset of ER+/HER2+ patients with low pCR rates following neoadjuvant chemotherapy ± anti-HER2 therapy. These patients may potentially be spared chemotherapy in favor of anti-HER2, endocrine therapy, and CDK 4/6 inhibitor combinations.

  6. A human recombinant monoclonal antibody to cocaine: Preparation, characterization and behavioral studies

    PubMed Central

    Eubanks, Lisa M.; Ellis, Beverly A.; Cai, Xiaoqing; Schlosburg, Joel E.; Janda, Kim D.

    2014-01-01

    Cocaine abuse remains prevalent worldwide and continues to be a major health concern; nonetheless, there is no effective therapy. Immunopharmacothery has emerged as a promising treatment strategy by which anti-cocaine antibodies bind to the drug blunting its effects. Previous passive immunization studies using our human monoclonal antibody, GNCgzk, resulted in protection against cocaine overdose and acute toxicity. To further realize the clinical potential of this antibody, a recombinant IgG form of the antibody has been produced in mammalian cells. This antibody displayed a high binding affinity for cocaine (low nanomolar) in line with the superior attributes of the GNCgzk antibody and reduced cocaine-induced ataxia in a cocaine overdose model. PMID:25205191

  7. Novel anti-EPHA2 antibody, DS-8895a for cancer treatment.

    PubMed

    Hasegawa, Jun; Sue, Mayumi; Yamato, Michiko; Ichikawa, Junya; Ishida, Saori; Shibutani, Tomoko; Kitamura, Michiko; Wada, Teiji; Agatsuma, Toshinori

    2016-11-01

    Overexpression of EPHA2 has been observed in multiple cancers and reported to be associated with poor prognosis. Here, we produced an afucosylated humanized anti-EPHA2 monoclonal antibody (mAb), DS-8895a for cancer treatment. The antibody recognizes the extracellular juxtamembrane region of EPHA2 and therefore can bind to both full-length and truncated forms of EPHA2, which are anchored to cell membranes and recently reported to be produced by post-translational cleavage in tumors. DS-8895a exhibited markedly increased antibody dependent cellular cytotoxicity (ADCC) in vitro and also inhibited tumor growth in EPHA2-positive human breast cancer MDA-MB-231 and human gastric cancer SNU-16 xenograft mouse models. Moreover, DS-8895a in combination with cisplatin (CDDP) showed better efficacy than each of the monotherapies did in the human gastric cancer model. These results suggest that a novel antibody, DS-8895a has therapeutic potential against EPHA2-expressing tumors.

  8. Novel anti-EPHA2 antibody, DS-8895a for cancer treatment

    PubMed Central

    Hasegawa, Jun; Sue, Mayumi; Yamato, Michiko; Ichikawa, Junya; Ishida, Saori; Shibutani, Tomoko; Kitamura, Michiko; Wada, Teiji; Agatsuma, Toshinori

    2016-01-01

    ABSTRACT Overexpression of EPHA2 has been observed in multiple cancers and reported to be associated with poor prognosis. Here, we produced an afucosylated humanized anti-EPHA2 monoclonal antibody (mAb), DS-8895a for cancer treatment. The antibody recognizes the extracellular juxtamembrane region of EPHA2 and therefore can bind to both full-length and truncated forms of EPHA2, which are anchored to cell membranes and recently reported to be produced by post-translational cleavage in tumors. DS-8895a exhibited markedly increased antibody dependent cellular cytotoxicity (ADCC) in vitro and also inhibited tumor growth in EPHA2-positive human breast cancer MDA-MB-231 and human gastric cancer SNU-16 xenograft mouse models. Moreover, DS-8895a in combination with cisplatin (CDDP) showed better efficacy than each of the monotherapies did in the human gastric cancer model. These results suggest that a novel antibody, DS-8895a has therapeutic potential against EPHA2-expressing tumors. PMID:27653549

  9. Characterization of a recombinant humanized anti-cocaine monoclonal antibody produced from multiple clones for the selection of a master cell bank candidate.

    PubMed

    Wetzel, Hanna N; Webster, Rose P; Saeed, Fatima O; Kirley, Terence L; Ball, William J; Norman, Andrew B

    2017-06-03

    We have generated a humanized anti-cocaine monoclonal antibody (mAb), which is at an advanced stage of pre-clinical development. We report here in vitro binding affinity studies, and in vivo pharmacokinetic and efficacy studies of the recombinant mAb. The overall aim was to characterize the recombinant antibody from each of the three highest producing transfected clones and to select one to establish a master cell bank. In mAb pharmacokinetic studies, after injection with h2E2 (120 mg/kg iv) blood was collected from the tail tip of mice over 28 days. Antibody concentrations were quantified using ELISA. The h2E2 concentration as a function of time was fit using a two-compartment pharmacokinetic model. To test in vivo efficacy, mice were injected with h2E2 (120 mg/kg iv), then one hour later injected with an equimolar dose of cocaine. Blood and brain were collected 5 min after cocaine administration. Cocaine concentrations were quantified using LC/MS. The affinity of the antibody for cocaine was determined using a [ 3 H] cocaine binding assay. All three antibodies had long elimination half-lives, 2-5 nM Kd for cocaine, and prevented cocaine's entry into the brain by sequestering it in the plasma. Pharmacokinetic and radioligand binding assays supported designation of the highest producing clone 85 as the master cell bank candidate. Overall, the recombinant h2E2 showed favorable binding properties, pharmacokinetics, and in vivo efficacy. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. A Potent HER3 Monoclonal Antibody That Blocks Both Ligand-Dependent and -Independent Activities: Differential Impacts of PTEN Status on Tumor Response.

    PubMed

    Xiao, Zhan; Carrasco, Rosa A; Schifferli, Kevin; Kinneer, Krista; Tammali, Ravinder; Chen, Hong; Rothstein, Ray; Wetzel, Leslie; Yang, Chunning; Chowdhury, Partha; Tsui, Ping; Steiner, Philipp; Jallal, Bahija; Herbst, Ronald; Hollingsworth, Robert E; Tice, David A

    2016-04-01

    HER3/ERBB3 is a kinase-deficient member of the EGFR family receptor tyrosine kinases (RTK) that is broadly expressed and activated in human cancers. HER3 is a compelling cancer target due to its important role in activation of the oncogenic PI3K/AKT pathway. It has also been demonstrated to confer tumor resistance to a variety of cancer therapies, especially targeted drugs against EGFR and HER2. HER3 can be activated by its ligand (heregulin/HRG), which induces HER3 heterodimerization with EGFR, HER2, or other RTKs. Alternatively, HER3 can be activated in a ligand-independent manner through heterodimerization with HER2 in HER2-amplified cells. We developed a fully human mAb against HER3 (KTN3379) that efficiently suppressed HER3 activity in both ligand-dependent and independent settings. Correspondingly, KTN3379 inhibited tumor growth in divergent tumor models driven by either ligand-dependent or independent mechanisms in vitro and in vivo Most intriguingly, while investigating the mechanistic underpinnings of tumor response to KTN3379, we discovered an interesting dichotomy in that PTEN loss, a frequently occurring oncogenic lesion in a broad range of cancer types, substantially blunted the tumor response in HER2-amplified cancer, but not in the ligand-driven cancer. To our knowledge, this represents the first study ascertaining the impact of PTEN loss on the antitumor efficacy of a HER3 mAb. KTN3379 is currently undergoing a phase Ib clinical trial in patients with advanced solid tumors. Our current study may help us optimize patient selection schemes for KTN3379 to maximize its clinical benefits. Mol Cancer Ther; 15(4); 689-701. ©2016 AACR. ©2016 American Association for Cancer Research.

  11. Human Anti-V3 HIV-1 Monoclonal Antibodies Encoded by the VH5-51/VL Lambda Genes Define a Conserved Antigenic Structure

    PubMed Central

    Gorny, Miroslaw K.; Sampson, Jared; Li, Huiguang; Jiang, Xunqing; Totrov, Maxim; Wang, Xiao-Hong; Williams, Constance; O'Neal, Timothy; Volsky, Barbara; Li, Liuzhe; Cardozo, Timothy; Nyambi, Phillipe; Zolla-Pazner, Susan; Kong, Xiang-Peng

    2011-01-01

    Preferential usage of immunoglobulin (Ig) genes that encode antibodies (Abs) against various pathogens is rarely observed and the nature of their dominance is unclear in the context of stochastic recombination of Ig genes. The hypothesis that restricted usage of Ig genes predetermines the antibody specificity was tested in this study of 18 human anti-V3 monoclonal Abs (mAbs) generated from unrelated individuals infected with various subtypes of HIV-1, all of which preferentially used pairing of the VH5-51 and VL lambda genes. Crystallographic analysis of five VH5-51/VL lambda-encoded Fabs complexed with various V3 peptides revealed a common three dimensional (3D) shape of the antigen-binding sites primarily determined by the four complementarity determining regions (CDR) for the heavy (H) and light (L) chains: specifically, the H1, H2, L1 and L2 domains. The CDR H3 domain did not contribute to the shape of the binding pocket, as it had different lengths, sequences and conformations for each mAb. The same shape of the binding site was further confirmed by the identical backbone conformation exhibited by V3 peptides in complex with Fabs which fully adapted to the binding pocket and the same key contact residues, mainly germline-encoded in the heavy and light chains of five Fabs. Finally, the VH5-51 anti-V3 mAbs recognized an epitope with an identical 3D structure which is mimicked by a single mimotope recognized by the majority of VH5-51-derived mAbs but not by other V3 mAbs. These data suggest that the identification of preferentially used Ig genes by neutralizing mAbs may define conserved epitopes in the diverse virus envelopes. This will be useful information for designing vaccine immunogen inducing cross-neutralizing Abs. PMID:22164215

  12. Correlation Between Quantitative HER-2 Protein Expression and Risk for Brain Metastases in HER-2+ Advanced Breast Cancer Patients Receiving Trastuzumab-Containing Therapy

    PubMed Central

    Duchnowska, Renata; Biernat, Wojciech; Szostakiewicz, Barbara; Sperinde, Jeff; Piette, Fanny; Haddad, Mojgan; Paquet, Agnes; Lie, Yolanda; Czartoryska-Arłukowicz, Bogumiła; Wysocki, Piotr; Jankowski, Tomasz; Radecka, Barbara; Foszczyńska-Kłoda, Małgorzata; Litwiniuk, Maria; Dȩbska, Sylwia; Weidler, Jodi; Huang, Weidong; Buyse, Marc; Bates, Michael

    2012-01-01

    Background. Patients with human epidermal growth factor receptor (HER)-2+ breast cancer are at particularly high risk for brain metastases; however, the biological basis is not fully understood. Using a novel HER-2 assay, we investigated the correlation between quantitative HER-2 expression in primary breast cancers and the time to brain metastasis (TTBM) in HER-2+ advanced breast cancer patients treated with trastuzumab. Methods. The study group included 142 consecutive patients who were administered trastuzumab-based therapy for HER-2+ metastatic breast cancer. HER-2/neu gene copy number was quantified as the HER-2/centromeric probe for chromosome 17 (CEP17) ratio by central laboratory fluorescence in situ hybridization (FISH). HER-2 protein was quantified as total HER-2 protein expression (H2T) by the HERmark® assay (Monogram Biosciences, Inc., South San Francisco, CA) in formalin-fixed, paraffin-embedded tumor samples. HER-2 variables were correlated with clinical features and TTBM was measured from the initiation of trastuzumab-containing therapy. Results. A higher H2T level (continuous variable) was correlated with shorter TTBM, whereas HER-2 amplification by FISH and a continuous HER-2/CEP17 ratio were not predictive (p = .013, .28, and .25, respectively). In the subset of patients that was centrally determined by FISH to be HER-2+, an above-the-median H2T level was significantly associated with a shorter TTBM (hazard ratio, [HR], 2.4; p = .005), whereas this was not true for the median HER-2/CEP17 ratio by FISH (p = .4). Correlation between a continuous H2T level and TTBM was confirmed on multivariate analysis (HR, 3.3; p = .024). Conclusions. These data reveal a strong relationship between the quantitative HER-2 protein expression level and the risk for brain relapse in HER-2+ advanced breast cancer patients. Consequently, quantitative assessment of HER-2 protein expression may inform and facilitate refinements in therapeutic treatment strategies for

  13. Correlation between quantitative HER-2 protein expression and risk for brain metastases in HER-2+ advanced breast cancer patients receiving trastuzumab-containing therapy.

    PubMed

    Duchnowska, Renata; Biernat, Wojciech; Szostakiewicz, Barbara; Sperinde, Jeff; Piette, Fanny; Haddad, Mojgan; Paquet, Agnes; Lie, Yolanda; Czartoryska-Arłukowicz, Bogumiła; Wysocki, Piotr; Jankowski, Tomasz; Radecka, Barbara; Foszczynska-Kłoda, Małgorzata; Litwiniuk, Maria; Debska, Sylwia; Weidler, Jodi; Huang, Weidong; Buyse, Marc; Bates, Michael; Jassem, Jacek

    2012-01-01

    Patients with human epidermal growth factor receptor (HER)-2+ breast cancer are at particularly high risk for brain metastases; however, the biological basis is not fully understood. Using a novel HER-2 assay, we investigated the correlation between quantitative HER-2 expression in primary breast cancers and the time to brain metastasis (TTBM) in HER-2+ advanced breast cancer patients treated with trastuzumab. The study group included 142 consecutive patients who were administered trastuzumab-based therapy for HER-2+ metastatic breast cancer. HER-2/neu gene copy number was quantified as the HER-2/centromeric probe for chromosome 17 (CEP17) ratio by central laboratory fluorescence in situ hybridization (FISH). HER-2 protein was quantified as total HER-2 protein expression (H2T) by the HERmark® assay (Monogram Biosciences, Inc., South San Francisco, CA) in formalin-fixed, paraffin-embedded tumor samples. HER-2 variables were correlated with clinical features and TTBM was measured from the initiation of trastuzumab-containing therapy. A higher H2T level (continuous variable) was correlated with shorter TTBM, whereas HER-2 amplification by FISH and a continuous HER-2/CEP17 ratio were not predictive (p = .013, .28, and .25, respectively). In the subset of patients that was centrally determined by FISH to be HER-2+, an above-the-median H2T level was significantly associated with a shorter TTBM (hazard ratio, [HR], 2.4; p = .005), whereas this was not true for the median HER-2/CEP17 ratio by FISH (p = .4). Correlation between a continuous H2T level and TTBM was confirmed on multivariate analysis (HR, 3.3; p = .024). These data reveal a strong relationship between the quantitative HER-2 protein expression level and the risk for brain relapse in HER-2+ advanced breast cancer patients. Consequently, quantitative assessment of HER-2 protein expression may inform and facilitate refinements in therapeutic treatment strategies for selected subpopulations of patients in this

  14. Characterization of two anti-dengue human monoclonal antibodies prepared from PBMCs of patients with dengue illness in Thailand.

    PubMed

    Li, Z-Y; Yamashita, A; Kawashita, N; Sasaki, T; Pan, Y; Ono, K-I; Ikuta, K; Li, Y-G

    2016-06-01

    The global spread of the four dengue virus (DENV) serotypes (dengue-1 to -4) has made this virus a major and growing public health concern. Generally, pre-existing neutralizing antibodies derived from primary infection play a significant role in protecting against subsequent infection with the same serotype. By contrast, these pre-existing antibodies are believed to mediate a non-protective response to subsequent heterotypic DENV infections, leading to the onset of dengue illness. In this study, two monoclonal antibodies prepared by using peripheral blood mononuclear cells (PBMCs) from patients with dengue fever were characterized. Epitope mapping revealed that amino acid residues 254-278 in domain II of the viral envelope protein E were the target region of these antibodies. A database search revealed that certain sequences in this epitope region showed high conservation among the four serotypes of DENV. These two human monoclonal antibodies could neutralize DENV-2,-4 more effectively than DENV-1,-3. The amino acid sequences could not explain this difference in neutralizing activity. However, the 3D structure results showed that amino acid 274 could be the critical residue for the difference in neutralization. These results may provide basic information for the development of a dengue vaccine.

  15. Combining Anti-ERBB3 Antibodies Specific for Domain I and Domain III Enhances the Anti-Tumor Activity over the Individual Monoclonal Antibodies

    PubMed Central

    D’Souza, Jimson W.; Shchaveleva, Irina; Marks, James D.; Litwin, Samuel; Robinson, Matthew K.

    2014-01-01

    Background Inappropriate signaling through the epidermal growth factor receptor family (EGFR1/ERBB1, ERBB2/HER2, ERBB3/HER3, and ERBB4/HER4) of receptor tyrosine kinases leads to unregulated activation of multiple downstream signaling pathways that are linked to cancer formation and progression. In particular, ERBB3 plays a critical role in linking ERBB signaling to the phosphoinositide 3-kinase and Akt signaling pathway and increased levels of ERBB3-dependent signaling is also increasingly recognized as a mechanism for acquired resistance to ERBB-targeted therapies. Methods We had previously reported the isolation of a panel of anti-ERBB3 single-chain Fv antibodies through use of phage-display technology. In the current study scFv specific for domain I (F4) and domain III (A5) were converted into human IgG1 formats and analyzed for efficacy. Results Treatment of cells with an oligoclonal mixture of the A5/F4 IgGs appeared more effective at blocking both ligand-induced and ligand-independent signaling through ERBB3 than either single IgG alone. This correlated with improved ability to inhibit the cell growth both as a single agent and in combination with other ERBB-targeted therapies. Treatment of NCI-N87 tumor xenografts with the A5/F4 oligoclonal led to a statistically significant decrease in tumor growth rate that was further enhanced in combination with trastuzumab. Conclusion These results suggest that an oligoclonal antibody mixture may be a more effective approach to downregulate ERBB3-dependent signaling. PMID:25386657

  16. Monoclonal antibodies against the rat liver glucocorticoid receptor.

    PubMed Central

    Okret, S; Wikström, A C; Wrange, O; Andersson, B; Gustafsson, J A

    1984-01-01

    Splenic cells from one BALB/c mouse and one C57/BL mouse, immunized with purified rat liver glucocorticoid receptor (GR), were fused with the mouse myeloma cell line Sp 2/0-Ag 14. Screening for production of anti-GR-antibodies by the hybridomas was carried out with an enzyme-linked immunosorbent assay, using partially purified rat liver GR as antigen. Further screening was by a second-antibody immunoprecipitation assay using [3H]triamcinolone acetonide-GR complex from rat liver cytosol as tracer. Hybridomas from 10 different microplate wells, positive in both assays, were successfully cloned by the limiting dilution method to monoclonality. The different origins of the monoclonal antibodies were confirmed by their various isoelectric points when analyzed by isoelectric focusing. Four of the monoclonal hybridoma cell lines secreted IgM antibodies; two, IgG1; three, IgG2a; and one, IgG2b. The GR-antibody complex was identified in glycerol density gradients by a shift of the 4S GR to an 8.5S or 19S GR-antibody complex when incubated with monoclonal IgG or IgM antibody, respectively. The 10 monoclonal antibodies recognized different determinants on the GR, all situated on that domain of the receptor that is separate from the ligand and DNA-binding domains. Also, the cross-reactivity to the mouse liver GR varied among the monoclonal antibodies. No cross-reactivity was observed to the human lymphocytic GR. NaDodSO4 electrophoresis of a 0.5% pure GR preparation followed by immunoblotting using one of the monoclonal antibodies identified a single peptide with a molecular weight of 94,000, identical to the purified rat liver GR. Images PMID:6200880

  17. Targeted delivery of doxorubicin into tumor cells by nanostructured lipid carriers conjugated to anti-EGFRvIII monoclonal antibody.

    PubMed

    Abdolahpour, Saeideh; Toliyat, Tayebeh; Omidfar, Kobra; Modjtahedi, Helmout; Wong, Albert J; Rasaee, Mohammad Javad; Kashanian, Susan; Paknejad, Maliheh

    2018-02-01

    Epidermal growth factor receptor variant III (EGFRvIII) is the most common variant of the EGF receptor in many human tumors. This variant is tumor specific and highly immunogenic, thus, it can be used as a target for targeted drug delivery toward tumor cells. The major aim of this study was to develop an EGFRvIII-mediated drug delivery system by anti-EGFRvIII monoclonal antibody (MAb) conjugated to doxorubicin (Dox)-loaded nanostructured lipid carriers (NLC) to enhance the targeting specificity and cytotoxic effect of Dox on EGFRvIII-overexpressing cell line. In our study, Dox was chosen as a hydrophobic cytotoxic drug and drug-loaded nanostructured lipid carriers (Dox-NLC) was prepared by solvent emulsification/evaporation method. In order to conjugate anti-EGFRvIII MAb to Dox-NLC, DSPE-PEG2000-NHS (1,2-distearoylphosphatidylethanolamine-polyethylene glycol 2000-NHS) was used as a linker. Physicochemical characteristics of antibody conjugated Dox-NLC (MAb-Dox-NLC), including particle size, zeta potential, entrapment efficiency and in vitro Dox release were investigated. Cytotoxicity of MAb-Dox-NLC against NIH-3T3 and HC2 20d2/c (EGFRvIII-transfected NIH-3T3) cell lines was evaluated. The MAb-Dox-NLC appeared to enhance the cytotoxic activity of targeted NLC against HC2 20d2/c cells. The cellular uptake percentage of targeted NLC by HC2 20d2/c cells was higher than that of NIH-3T3 cells, indicating that EGFRvIII can specifically target HC2 20d2/c cells. In conclusion, anti-EGFRvIII MAb-targeted NLC may be considered as an effective nanocarrier for targeted drug delivery.

  18. Microenvironment-Mediated Mechanisms of Resistance to HER2 Inhibitors Differ between HER2+ Breast Cancer Subtypes.

    PubMed

    Watson, Spencer S; Dane, Mark; Chin, Koei; Tatarova, Zuzana; Liu, Moqing; Liby, Tiera; Thompson, Wallace; Smith, Rebecca; Nederlof, Michel; Bucher, Elmar; Kilburn, David; Whitman, Matthew; Sudar, Damir; Mills, Gordon B; Heiser, Laura M; Jonas, Oliver; Gray, Joe W; Korkola, James E

    2018-03-28

    Extrinsic signals are implicated in breast cancer resistance to HER2-targeted tyrosine kinase inhibitors (TKIs). To examine how microenvironmental signals influence resistance, we monitored TKI-treated breast cancer cell lines grown on microenvironment microarrays composed of printed extracellular matrix proteins supplemented with soluble proteins. We tested ∼2,500 combinations of 56 soluble and 46 matrix microenvironmental proteins on basal-like HER2+ (HER2E) or luminal-like HER2+ (L-HER2+) cells treated with the TKIs lapatinib or neratinib. In HER2E cells, hepatocyte growth factor, a ligand for MET, induced resistance that could be reversed with crizotinib, an inhibitor of MET. In L-HER2+ cells, neuregulin1-β1 (NRG1β), a ligand for HER3, induced resistance that could be reversed with pertuzumab, an inhibitor of HER2-HER3 heterodimerization. The subtype-specific responses were also observed in 3D cultures and murine xenografts. These results, along with bioinformatic pathway analysis and siRNA knockdown experiments, suggest different mechanisms of resistance specific to each HER2+ subtype: MET signaling for HER2E and HER2-HER3 heterodimerization for L-HER2+ cells. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Discovery of Novel Human Epidermal Growth Factor Receptor-2 Inhibitors by Structure-based Virtual Screening.

    PubMed

    Shi, Zheng; Yu, Tian; Sun, Rong; Wang, Shan; Chen, Xiao-Qian; Cheng, Li-Jia; Liu, Rong

    2016-01-01

    Human epidermal growth factor receptor-2 (HER2) is a trans-membrane receptor like protein, and aberrant signaling of HER2 is implicated in many human cancers, such as ovarian cancer, gastric cancer, and prostate cancer, most notably breast cancer. Moreover, it has been in the spotlight in the recent years as a promising new target for therapy of breast cancer. Since virtual screening has become an integral part of the drug discovery process, it is of great significant to identify novel HER2 inhibitors by structure-based virtual screening. In this study, we carried out a series of elegant bioinformatics approaches, such as virtual screening and molecular dynamics (MD) simulations to identify HER2 inhibitors from Food and Drug Administration-approved small molecule drug as potential "new use" drugs. Molecular docking identified top 10 potential drugs which showed spectrum affinity to HER2. Moreover, MD simulations suggested that ZINC08214629 (Nonoxynol-9) and ZINC03830276 (Benzonatate) might exert potential inhibitory effects against HER2-targeted anti-breast cancer therapeutics. Together, our findings may provide successful application of virtual screening studies in the lead discovery process, and suggest that our discovered small molecules could be effective HER2 inhibitor candidates for further study. A series of elegant bioinformatics approaches, including virtual screening and molecular dynamics (MD) simulations were took advantage to identify human epidermal growth factor receptor-2 (HER2) inhibitors. Molecular docking recognized top 10 candidate compounds, which showed spectrum affinity to HER2. Further, MD simulations suggested that ZINC08214629 (Nonoxynol-9) and ZINC03830276 (Benzonatate) in candidate compounds were identified as potential "new use" drugs against HER2-targeted anti-breast cancer therapeutics. Abbreviations used: HER2: Human epidermal growth factor receptor-2, FDA: Food and Drug Administration, PDB: Protein Database Bank, RMSDs: Root mean

  20. Could HER2 heterogeneity open new therapeutic options in patients with HER2- primary breast cancer

    DTIC Science & Technology

    is an initial proof-of-concept that targeted imaging may help identify patients eligible for targeted therapies. However, six of nine patients have...needed. A first-in-human trial of 89Zr-pertuzumab PET/CT was performed in six patients with HER2-positive metastatic breast cancer, demonstrating

  1. Pharmacokinetics and tolerability of human mouse chimeric anti-CD22 monoclonal antibody in Chinese patients with CD22-positive non-Hodgkin lymphoma.

    PubMed

    Li, Su; Zhang, Dongsheng; Sun, Jian; Li, Zhinming; Deng, Liting; Zou, Benyan; Zhan, Jing; Jiang, Wenqi

    2012-01-01

    The safety and pharmacokinetics assessment of antibodies targeting CD22 (e.g., epratuzumab) have been established in western Caucasian populations, but there are no reports of the effects in Chinese populations. This dose-escalation study examines the safety, pharmacokinetics and biologic effects of multiple doses of anti-CD22 human-murine chimeric monoclonal antibody SM03 in 21 Chinese patients with CD22-positive non-Hodgkin lymphoma. Most of drug-related adverse events (AEs) were mild and reversible. Two patients experienced serious AEs (hemorrhage); one patient had grade 4 neutropenia; one patient had asymptomatic grade III prolongation of activated partial thromboplastin time (APTT). Major AEs included fever (71%), prolongation of APTT (42.8%), leukocytopenia (44.4%), alanine transaminase elevation (28.6%), elevated serum creatinine (23.8%) and injection site skin redness (14.3%). Circulating B cells transiently decreased without significant effects on T cells or immunoglobulin levels. Pharmacokinetic data revealed that mean maximum observed SM03 concentration and mean AUC from time zero to infinity increased in a dose-dependent manner up to 360 mg/m (2) SM03. Mean clearance was similar at doses ≤ 360 mg/m (2) and decreased significantly at dose 480 mg/m (2), supporting saturation of B-cell binding at 360 mg/m (2). Across all dose levels and histologies, one patient achieved partial response at 480 mg/m (2) dose; 14 patients had stable disease as best response and four patients progressed. Overall, SM03 was tolerated at doses ranging from 60-480 mg/m (2) and had potential efficacy in Chinese patients with follicular lymphoma.

  2. Improved Antibodies Against ERBB4/HER4 | NCI Technology Transfer Center | TTC

    Cancer.gov

    The Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Molecular Neurobiology seeks parties interested in licensing or collaborative research to further evaluate or commercialize specific rabbit monoclonal antibodies generated against the ErbB4 receptor (also known as HER4) that have been validated for specificity using tissue sections and extracts from ErbB4 knockout mice.

  3. Human anti-CD30 recombinant antibodies by guided phage antibody selection using cell panning

    PubMed Central

    Klimka, A; Matthey, B; Roovers, R C; Barth, S; Arends, J-W; Engert, A; Hoogenboom, H R

    2000-01-01

    In various clinical studies, Hodgkin’s patients have been treated with anti-CD30 immunotherapeutic agents and have shown promising responses. One of the problems that appeared from these studies is the development of an immune response against the non-human therapeutics, which limits repeated administration and reduces efficacy. We have set out to make a recombinant, human anti-CD30 single-chain variable fragment (scFv) antibody, which may serve as a targeting moiety with reduced immunogenicity and more rapid tumour penetration in similar clinical applications. Rather than selecting a naive phage antibody library on recombinant CD30 antigen, we used guided selection of a murine antibody in combination with panning on the CD30-positive cell line L540. The murine monoclonal antibody Ki-4 was chosen as starting antibody, because it inhibits the shedding of the extracellular part of the CD30 antigen. This makes the antibody better suited for CD30-targeting than most other anti-CD30 antibodies. We have previously isolated the murine Ki-4 scFv by selecting a mini-library of hybridoma-derived phage scFv-antibodies via panning on L540 cells. Here, we report that phage display technology was successfully used to obtain a human Ki-4 scFv version by guided selection. The murine variable heavy (VH) and light (VL) chain genes of the Ki-4 scFv were sequentially replaced by human V gene repertoires, while retaining only the major determinant for epitope-specificity: the heavy-chain complementarity determining region 3 (CDR3) of murine Ki-4. After two rounds of chain shuffling and selection by panning on L540 cells, a fully human anti-CD30 scFv was selected. It competes with the parental monoclonal antibody Ki-4 for binding to CD30, inhibits the shedding of the extracellular part of the CD30 receptor from L540 cells and is thus a promising candidate for the generation of anti-CD30 immunotherapeutics. © 2000 Cancer Research Campaign PMID:10901379

  4. Phosphatidylcholine-specific phospholipase C inhibition reduces HER2-overexpression, cell proliferation and in vivo tumor growth in a highly tumorigenic ovarian cancer model

    PubMed Central

    Spadaro, Francesca; Abalsamo, Laura; Pisanu, Maria Elena; Ricci, Alessandro; Cecchetti, Serena; Altabella, Luisa; Buoncervello, Maria; Lozneanu, Ludmila; Bagnoli, Marina; Ramoni, Carlo; Canevari, Silvana; Mezzanzanica, Delia

    2017-01-01

    Antagonizing the oncogenic effects of human epidermal growth factor receptor 2 (HER2) with current anti-HER2 agents has not yet yielded major progress in the treatment of advanced HER2-positive epithelial ovarian cancer (EOC). Using preclinical models to explore alternative molecular mechanisms affecting HER2 overexpression and oncogenicity may lead to new strategies for EOC patient treatment. We previously reported that phosphatidylcholine-specific phospholipase C (PC-PLC) exerts a pivotal role in regulating HER2 overexpression in breast cancer cells. The present study, conducted on two human HER2-overexpressing EOC cell lines - SKOV3 and its in vivo-passaged SKOV3.ip cell variant characterized by enhanced in vivo tumorigenicity - and on SKOV3.ip xenografts implanted in SCID mice, showed: a) about 2-fold higher PC-PLC and HER2 protein expression levels in SKOV3.ip compared to SKOV3 cells; b) physical association of PC-PLC with HER2 in non-raft domains; c) HER2 internalization and ca. 50% reduction of HER2 mRNA and protein expression levels in SKOV3.ip cells exposed to the PC-PLC inhibitor tricyclodecan-9-yl-potassium xanthate (D609); d) differential effects of D609 and trastuzumab on HER2 protein expression and cell proliferation; e) decreased in vivo tumor growth in SKOV3.ip xenografts during in vivo treatment with D609; f) potential use of in vivo magnetic resonance spectroscopy (MRS) and imaging (MRI) parameters as biomarkers of EOC response to PC-PLC inhibition. Overall, these findings support the view that PC-PLC inhibition may represent an effective means to target the tumorigenic effects of HER2 overexpression in EOC and that in vivo MR approaches can efficiently monitor its effects. PMID:28903399

  5. Evaluation of HER-2/neu gene amplification and overexpression: comparison of frequently used assay methods in a molecularly characterized cohort of breast cancer specimens.

    PubMed

    Press, Michael F; Slamon, Dennis J; Flom, Kerry J; Park, Jinha; Zhou, Jian-Yuan; Bernstein, Leslie

    2002-07-15

    To compare and evaluate HER-2/neu clinical assay methods. One hundred seventeen breast cancer specimens with known HER-2/neu amplification and overexpression status were assayed with four different immunohistochemical assays and two different fluorescence in situ hybridization (FISH) assays. The accuracy of the FISH assays for HER-2/neu gene amplification was high, 97.4% for the Vysis PathVision assay (Vysis, Inc, Downers Grove, IL) and 95.7% for the the Ventana INFORM assay (Ventana, Medical Systems, Inc, Tucson, AZ). The immunohistochemical assay with the highest accuracy for HER-2/neu overexpression was obtained with R60 polyclonal antibody (96.6%), followed by immunohistochemical assays performed with 10H8 monoclonal antibody (95.7%), the Ventana CB11 monoclonal antibody (89.7%), and the DAKO HercepTest (88.9%; Dako, Corp, Carpinteria, CA). Only the sensitivities, and therefore, overall accuracy, of the DAKO Herceptest and Ventana CB11 immunohistochemical assays were significantly different from the more sensitive FISH assay. Based on these findings, the FISH assays were highly accurate, with immunohistochemical assays performed with R60 and 10H8 nearly as accurate. The DAKO HercepTest and the Ventana CB11 immunohistochemical assay were statistically significantly different from the Vysis FISH assay in evaluating these previously molecularly characterized breast cancer specimens.

  6. Combination of an agonistic anti-CD40 monoclonal antibody and the COX-2 inhibitor celecoxib induces anti-glioma effects by promotion of type-1 immunity in myeloid cells and T-cells

    PubMed Central

    Kosaka, Akemi; Ohkuri, Takayuki

    2014-01-01

    Malignant gliomas are heavily infiltrated by immature myeloid cells that mediate immuno-suppression. Agonistic CD40 monoclonal antibody (mAb) has been shown to activate myeloid cells and promote antitumor immunity. Our previous study has also demonstrated blockade of cyclooxygenase-2 (COX-2) reduces immunosuppressive myeloid cells, thereby suppressing glioma development in mice. We therefore hypothesized that a combinatory strategy to modulate myeloid cells via two distinct pathways, i.e., CD40/CD40L stimulation and COX-2 blockade, would enhance anti-glioma immunity. We used three different mouse glioma models to evaluate therapeutic effects and underlying mechanisms of a combination regimen with an agonist CD40 mAb and the COX-2 inhibitor celecoxib. Treatment of glioma-bearing mice with the combination therapy significantly prolonged survival compared with either anti-CD40 mAb or celecoxib alone. The combination regimen promoted maturation of CD11b+ cells in both spleen and brain, and enhanced Cxcl10 while suppressing Arg1 in CD11b+Gr-1+ cells in the brain. Anti-glioma activity of the combination regimen was T-cell dependent because depletion of CD4+ and CD8+ cells in vivo abrogated the anti-glioma effects. Furthermore, the combination therapy significantly increased the frequency of CD8+ T-cells, enhanced IFN-γ-production and reduced CD4+CD25+Foxp3+ T regulatory cells in the brain, and induced tumor-antigen-specific T-cell responses in lymph nodes. Our findings suggest that the combination therapy of anti-CD40 mAb with celecoxib enhances anti-glioma activities via promotion of type-1 immunity both in myeloid cells and T-cells. PMID:24878890

  7. A novel dendritic cell-based immunization approach for the induction of durable Th1-polarized anti-HER-2/neu responses in women with early breast cancer

    PubMed Central

    Koski, Gary K.; Koldovsky, Ursula; Xu, Shuwen; Mick, Rosemarie; Sharma, Anupama; Fitzpatrick, Elizabeth; Weinstein, Susan; Nisenbaum, Harvey; Levine, Bruce L; Fox, Kevin; Zhang, Paul; Czerniecki, Brian J

    2011-01-01

    Twenty-seven subjects with HER-2/neu over-expressing ductal carcinoma in situ of the breast were enrolled in a neoadjuvant immunization trial for safety and immunogenicity of DC1-polarized dendritic cells (DC1) pulsed with six HER-2/neu promiscuous MHC class II-binding peptides, plus two additional HLA-A2.1 class I-binding peptides. DC1 were generated with IFN-γ plus a special clinical-grade bacterial endotoxin (LPS) and administered directly into groin lymph nodes four times at weekly intervals prior to scheduled surgical resection of DCIS. Subjects were monitored for the induction of new or enhanced anti-peptide reactivity by IFN-γ ELIspot and ELISA assays performed on Th cells obtained from peripheral blood or excised sentinel lymph nodes. Responses by CTL against HLA-A2.1-binding peptides were measured using peptide-pulsed T2 target cells or HER-2/neu-expressing or non-expressing tumor cell lines. DC1 showed surface phenotype indistinct from “gold standard” inflammatory cocktail-activated DC, but displayed a number of distinguishing functional characteristics including the secretion of soluble factors and enhanced “killer DC” capacity against tumor cells in vitro. Post-immunization, we observed sensitization of Th cells to at least 1 class II peptide in 22 of 25 (88%, 95% exact CI 68.8 – 97.5%) evaluable subjects, while eleven of 13 (84.6%, 95% exact CI 64 – 99.8%) HLA-A2.1 subjects were successfully sensitized to class I peptides. Perhaps most importantly, anti-HER-2/neu peptide responses were observed up to 52 months post-immunization. These data show even in the presence of early breast cancer such DC1 are potent inducers of durable type I-polarized immunity, suggesting potential clinical value for development of cancer immunotherapy. PMID:22130160

  8. Effect of anti-GM2 antibodies on rat sciatic nerve: electrophysiological and morphological study.

    PubMed

    Ortiz, Nicolau; Sabaté, M Mar; Garcia, Neus; Santafe, Manel M; Lanuza, M Angel; Tomàs, Marta; Tomàs, Josep

    2009-03-31

    We found that a monoclonal human IgM anti-GM2 was fixed in rat sciatic axons and Schwann cells and was able to activate human complement. The passive transfer of IgM and complement in sciatic nerves can induce an acute alteration in nerve conduction. When the transfer of IgM plus complement was repeated for 10 days, the compound action motor potential amplitude was very low and the morphological study showed axons and myelin damage. Without human complement, IgM can only slightly disorganize the myelin by separating some layers, probably by interfering with the functional role of gangliosides in the myelin package.

  9. A sandwich-type electrochemical immunosensor based on in situ silver deposition for determination of serum level of HER2 in breast cancer patients.

    PubMed

    Shamsipur, Mojtaba; Emami, Mahdi; Farzin, Leila; Saber, Reza

    2018-04-30

    The sensitive quantification of Human Epidermal growth factor Receptor 2 (HER2), as a key prognostic tumor marker, plays a critical role in screening, early diagnosis and management of breast cancer. This paper describes a sandwich-type immunoassay with silver signal enhancement strategy for highly sensitive detection of HER2. For this purpose, the target capturing step was designed by functionalization of 3-aminopropyltrimethoxysilane coated magnetite nanoparticles with antibody (antiHER2/APTMS-Fe 3 O 4 ), as a platform bioconjugate (PB), and immobilized at a bare GCE. Then, in the presence of label-free immunosensor, the PB was covered by magnetic gold nanoparticles self-assembled with thiolated antibodies (antiHER2/Hyd@AuNPs-APTMS-Fe 3 O 4 ) containing chemically reduced silver ions, as a label bioconjugate (LB). Under optimum conditions, a linear relationship between the differential pulse voltammetric (DPV) stripping signal of silver and the logarithm of HER2 concentrations was obtained in the range of 5.0 × 10 -4 -50.0ngmL -1 (R 2 = 0.9906) with a detection limit of 2.0 × 10 -5 ngmL -1 . The effectiveness of this protocol was evaluated experimentally through employing of designed immunosensor for detection of the serum level of tumor marker. The good consistency of the results with those obtained by the enzyme-linked immunosorbent assay (ELISA) conventional method (p-value of < 0.05) showed that this immunosensor can be applied for the testing of HER2 in clinical samples of breast cancer patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Carboxyl group footprinting mass spectrometry and molecular dynamics identify key interactions in the HER2-HER3 receptor tyrosine kinase interface.

    PubMed

    Collier, Timothy S; Diraviyam, Karthikeyan; Monsey, John; Shen, Wei; Sept, David; Bose, Ron

    2013-08-30

    The HER2 receptor tyrosine kinase is a driver oncogene in many human cancers, including breast and gastric cancer. Under physiologic levels of expression, HER2 heterodimerizes with other members of the EGF receptor/HER/ErbB family, and the HER2-HER3 dimer forms one of the most potent oncogenic receptor pairs. Previous structural biology studies have individually crystallized the kinase domains of HER2 and HER3, but the HER2-HER3 kinase domain heterodimer structure has yet to be solved. Using a reconstituted membrane system to form HER2-HER3 kinase domain heterodimers and carboxyl group footprinting mass spectrometry, we observed that HER2 and HER3 kinase domains preferentially form asymmetric heterodimers with HER3 and HER2 monomers occupying the donor and acceptor kinase positions, respectively. Conformational changes in the HER2 activation loop, as measured by changes in carboxyl group labeling, required both dimerization and nucleotide binding but did not require activation loop phosphorylation at Tyr-877. Molecular dynamics simulations on HER2-HER3 kinase dimers identify specific inter- and intramolecular interactions and were in good agreement with MS measurements. Specifically, several intermolecular ionic interactions between HER2 Lys-716-HER3 Glu-909, HER2 Glu-717-HER3 Lys-907, and HER2 Asp-871-HER3 Arg-948 were identified by molecular dynamics. We also evaluated the effect of the cancer-associated mutations HER2 D769H/D769Y, HER3 E909G, and HER3 R948K (also numbered HER3 E928G and R967K) on kinase activity in the context of this new structural model. This study provides valuable insights into the EGF receptor/HER/ErbB kinase structure and interactions, which can guide the design of future therapies.

  11. Nuclear HER4 mediates acquired resistance to trastuzumab and is associated with poor outcome in HER2 positive breast cancer

    PubMed Central

    Nafi, Siti Norasikin Mohd; Generali, Daniele; Kramer-Marek, Gabriela; Gijsen, Merel; Strina, Carla; Cappelletti, Mariarosa; Andreis, Daniele; Haider, Syed; Li, Ji-Liang; Bridges, Esther; Capala, Jacek; Ioannis, Roxanis; Harris, Adrian L; Kong, Anthony

    2014-01-01

    The role of HER4 in breast cancer is controversial and its role in relation to trastuzumab resistance remains unclear. We showed that trastuzumab treatment and its acquired resistance induced HER4 upregulation, cleavage and nuclear translocation. However, knockdown of HER4 by specific siRNAs increased trastuzumab sensitivity and reversed its resistance in HER2 positive breast cancer cells. Preventing HER4 cleavage by a γ-secretase inhibitor and inhibiting HER4 tyrosine kinase activity by neratinib decreased trastuzumab-induced HER4 nuclear translocation and enhanced trastuzumab response. There was also increased nuclear HER4 staining in the tumours from BT474 xenograft mice and human patients treated with trastuzumab. Furthermore, nuclear HER4 predicted poor clinical response to trastuzumab monotherapy in patients undergoing a window study and was shown to be an independent poor prognostic factor in HER2 positive breast cancer. Our data suggest that HER4 plays a key role in relation to trastuzumab resistance in HER2 positive breast cancer. Therefore, our study provides novel findings that HER4 activation, cleavage and nuclear translocation influence trastuzumab sensitivity and resistance in HER2 positive breast cancer. Nuclear HER4 could be a potential prognostic and predictive biomarker and understanding the role of HER4 may provide strategies to overcome trastuzumab resistance in HER2 positive breast cancer. PMID:25153719

  12. Immunoglobulin gene usage in the human anti-pathogen response.

    PubMed

    Newkirk, M M; Rioux, J D

    1995-09-01

    The human antibody response to foreign pathogens is generated to a relatively small number of target surface proteins and carbohydrates that nonetheless have an extensive array of epitopes. The study of human monoclonal antibodies to different pathogens shows that there are a diversity of mechanisms used to generate a sufficient repertoire of antibodies to combat the invading pathogens. Although many different immunoglobulin gene elements are used to construct the anti-pathogen response, some elements are used more often than would be expected if all elements were used randomly. For example, the immune response to Haemophilus influenzae polysaccharide appears to be quite narrow, being restricted primarily to a specific heavy-chain gene, 3-15, and a lambda light-chain family II member, 4A. In contrast, for the immune response to cytomegalovirus proteins, a wider group of gene elements is needed. It is also surprising that despite an investigator bias for IgG- rather than IgM-secreting immortal B cells (because of their high affinity and neutralizing abilities), 26% of light chains and 13% of heavy chains showed a very low level of somatic mutation, equivalent to an IgM molecule that has not undergone affinity maturation. Although some highly mutated IgG molecules are present in the anti-pathogen response, most of the monoclonal antibodies specific for viruses or bacteria have a level of somatic hypermutation similar to that of the adult IgM repertoire. A number of studies have shown that there are similarities in the antibody responses to pathogens and to self (autoantibodies).(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Synthetic Human Monoclonal Antibodies toward Staphylococcal Enterotoxin B (SEB) Protective against Toxic Shock Syndrome*

    PubMed Central

    Karauzum, Hatice; Chen, Gang; Abaandou, Laura; Mahmoudieh, Mahta; Boroun, Atefeh R.; Shulenin, Sergey; Devi, V. Sathya; Stavale, Eric; Warfield, Kelly L.; Zeitlin, Larry; Roy, Chad J.; Sidhu, Sachdev S.; Aman, M. Javad

    2012-01-01

    Staphylococcal enterotoxin B (SEB) is a potent toxin that can cause toxic shock syndrome and act as a lethal and incapacitating agent when used as a bioweapon. There are currently no vaccines or immunotherapeutics available against this toxin. Using phage display technology, human antigen-binding fragments (Fabs) were selected against SEB, and proteins were produced in Escherichia coli cells and characterized for their binding affinity and their toxin neutralizing activity in vitro and in vivo. Highly protective Fabs were converted into full-length IgGs and produced in mammalian cells. Additionally, the production of anti-SEB antibodies was explored in the Nicotiana benthamiana plant expression system. Affinity maturation was performed to produce optimized lead anti-SEB antibody candidates with subnanomolar affinities. IgGs produced in N. benthamiana showed characteristics comparable with those of counterparts produced in mammalian cells. IgGs were tested for their therapeutic efficacy in the mouse toxic shock model using different challenge doses of SEB and a treatment with 200 μg of IgGs 1 h after SEB challenge. The lead candidates displayed full protection from lethal challenge over a wide range of SEB challenge doses. Furthermore, mice that were treated with anti-SEB IgG had significantly lower IFNγ and IL-2 levels in serum compared with mock-treated mice. In summary, these anti-SEB monoclonal antibodies represent excellent therapeutic candidates for further preclinical and clinical development. PMID:22645125

  14. A first-in-human pharmacodynamic and pharmacokinetic study of a fully human anti-glucagon receptor monoclonal antibody in normal healthy volunteers.

    PubMed

    Kostic, Ana; King, Thomas Alexander; Yang, Feng; Chan, Kuo-Chen; Yancopoulos, George D; Gromada, Jesper; Harp, Joyce B

    2018-02-01

    Glucagon receptor (GCGR) blockers are being investigated as potential therapeutics for type 1 and type 2 diabetes. Here we report the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of REGN1193, a fully human glucagon receptor blocking monoclonal antibody from a first-in-human healthy volunteer randomized double-blinded trial. Healthy men and women received single ascending doses of REGN1193 ranging from 0.05 to 0.6 mg/kg (n = 42) or placebo (n = 14) intravenously. Safety, tolerability and PK were assessed over 106 days. The glucose-lowering effect of REGN1193 was assessed after induction of hyperglycaemia by serial glucagon challenges. REGN1193 was generally well tolerated. There were small (<3× the upper limit of normal) and transient dose-dependent increases in hepatic aminotransferases. No increase in LDL-C was observed. Hypoglycaemia, assessed as laboratory blood glucose ≤70 mg/dL, occurred in 6/14 (43%) subjects on placebo and 27/42 (57%) on REGN1193 across all dose groups. All episodes of hypoglycaemia were asymptomatic, >50 mg/dL, and did not require treatment or medical assistance. Concentration-time profiles suggest a 2-compartment disposition and marked nonlinearity, consistent with target-mediated clearance. REGN1193 inhibited the glucagon-stimulated glucose increase in a dose-dependent manner. The 0.6 mg/kg dose inhibited the glucagon-induced glucose area under the curve for 0 to 90 minutes (AUC 0-90 minutes ) by 80% to 90% on days 3 and 15, while blunting the increase in C-peptide. REGN1193 dose-dependently increased total GLP-1, GLP-2 and glucagon, with plasma levels returning to baseline by day 29 in all dose groups. REGN1193, a GCGR-blocking monoclonal antibody, produced a safety, tolerability and PK/PD profile suitable for further clinical development. The occurrence of transient elevations in serum hepatic aminotransferases observed here and reported with several small molecule glucagon receptor

  15. HER2-positive breast cancer: Current and new therapeutic strategies.

    PubMed

    Escrivá-de-Romaní, Santiago; Arumí, Miriam; Bellet, Meritxell; Saura, Cristina

    2018-06-01

    Since the identification of the HER2 receptor amplification as an adverse prognostic factor that defined a special subtype of metastatic breast cancer, there has been a substantial improvement in survival of patients affected with this disease due to the development of anti-HER2 targeted therapies. The approval of trastuzumab and pertuzumab associated to a taxane in first line and subsequent treatment with the antibody-drug conjugate T-DM1 has certainly contributed to achieve these outcomes. The Tyrosine Kinase Inhibitor lapatinib was also approved in the basis of an improvement in progression free survival, becoming another commonly used treatment in combination with capecitabine. Inevitably, despite these therapeutic advances most patients progress on therapy due to primary or acquired resistance or because of an incorrect HER2 positivity assessment. Hence, it is crucial to correctly categorize HER2 amplified tumors and define mechanisms of resistance to design effective new treatment approaches. In addition, identifying biomarkers of response or resistance permits to tailor the therapeutic options for each patient sparing them from unnecessary toxicity as well as improving their outcomes. The aim of this review is to examine new strategies in development to treat HER2-positive metastatic breast cancer referring to the mechanisms of action of new drugs and new combinations including results reported so far. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Cloning of the first human anti-JCPyV/VP1 neutralizing monoclonal antibody: epitope definition and implications in risk stratification of patients under natalizumab therapy.

    PubMed

    Diotti, Roberta Antonia; Mancini, Nicasio; Clementi, Nicola; Sautto, Giuseppe; Moreno, Guisella Janett; Criscuolo, Elena; Cappelletti, Francesca; Man, Petr; Forest, Eric; Remy, Louise; Giannecchini, Simone; Clementi, Massimo; Burioni, Roberto

    2014-08-01

    JC virus (JCPyV) has gained novel clinical importance as cause of progressive multifocal leukoencephalopathy (PML), a rare demyelinating disease recently associated to immunomodulatory drugs, such as natalizumab used in multiple sclerosis (MS) cases. Little is known about the mechanisms leading to PML, and this makes the need of PML risk stratification among natalizumab-treated patients very compelling. Clinical and laboratory-based risk-stratification markers have been proposed, one of these is represented by the JCPyV-seropositive status, which includes about 54% of MS patients. We recently proposed to investigate the possible protective role of neutralizing humoral immune response in preventing JCPyV reactivation. In this proof-of-concept study, by cloning the first human monoclonal antibody (GRE1) directed against a neutralizing epitope on JCPyV/VP1, we optimized a robust anti-JCPyV neutralization assay. This allowed us to evaluate the neutralizing activity in JCPyV-positive sera from MS patients, demonstrating the lack of correlation between the level of anti-JCPyV antibody and anti-JCPyV neutralizing activity. Relevant consequences may derive from future clinical studies induced by these findings; indeed the study of the serum anti-JCPyV neutralizing activity could allow not only a better risk stratification of the patients during natalizumab treatment, but also a better understanding of the pathophysiological mechanisms leading to PML, highlighting the contribution of peripheral versus central nervous system JCPyV reactivation. Noteworthy, the availability of GRE1 could allow the design of novel immunoprophylactic strategies during the immunomodulatory treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Pattern of HER-2 Gene Amplification and Protein Expression in Benign, Borderline, and Malignant Ovarian Serous and Mucinous Neoplasms.

    PubMed

    Mohammed, Rabab A A; Makboul, Rania; Elsers, Dalia A H; Elsaba, Tarek M A M; Thalab, Abeer M A B; Shaaban, Omar M

    2017-01-01

    Amplification of HER-2 gene and overexpression of HER-2 receptor play a significant role in the progression of a number of malignancies such as breast cancer. Trastuzumab (anti-HER-2 therapeutic agent) has been used successfully in treatment of breast cancer. The aim of this study was to assess the pattern of HER-2 gene amplification and of HER-2 receptor expression in a spectrum of serous and mucinous ovarian tumors to determine whether HER-2 is altered in these neoplasms similar to that occurring in breast cancer. Formalin-fixed paraffin-embedded microarray tissue sections from 212 specimens were stained with HER-2 antibody using immunohistochemistry and with anti-HER-2 DNA probe using chromogenic in situ hybridization. Specimens consisted of 65 benign tumors (50 serous and 15 mucinous), 26 borderline (13 serous and 13 mucinous), 73 malignant tumors (53 serous carcinoma and 20 mucinous carcinoma), 18 metastatic deposits (13 serous and 5 mucinous), in addition to 30 normal tissues (16 ovarian surface and 14 normal fallopian tube). HER-2 protein-positive expression was not detected in the normal or the benign tissues. Borderline neoplasms showed positive staining, but no overexpression. HER-2 overexpression was seen only in 4 carcinoma specimens: 1/53 (1.8%) primary serous carcinomas and 3/20 (15%) primary mucinous carcinomas. HER-2 gene amplification was seen in 4 specimens: 2 primary mucinous carcinomas and 2 malignant deposits of these 2 mucinous carcinomas. In conclusion, alteration of HER-2 was not detected in ovarian serous neoplasms; however, in mucinous carcinoma, HER-2 amplification and overexpression occur.

  18. Tissue distribution and serum kinetics of T101 monoclonal antibody during passive anti-cancer therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shawler, D.L.; Beauregard, J.; Halpern, S.E.

    We have administered fifty-six 24 hr infusions of the anti-human T-cell monoclonal antibody T101 to 10 patients with cutaneous T-cell lymphoma (CTCL) and 6 patients with chronic lymphocytic leukemia (CLL) in doses of 10, 50, 100, 150, and 500 mg. The larger doses of T101 resulted in higher, more persistent serum T101 concentrations, and CTCL patients generally developed higher serum T101 levels than CLL patients given equivalent doses. The presence of host anti-mIgG antibodies prior to infusion was associated with decreased serum concentrations of T101. Treatments that demonstrated measurable serum T101 levels were also associated with in vivo T101 bindingmore » and cytodestruction of circulating target cells. Immunofluorescence analysis of bone marrow and lymph node biopsies in CLL, and skin biopsies in CTCL, suggested that T101 had reached extravascular tumor sites. Infusion of /sup 111/In-conjugated T101 showed uptake in the liver, spleen, lymph nodes, and (in CTCL) skin infiltrates. Our data demonstrate the tissue distribution of T101 and suggest that immunoconjugates of T101 with toxins, drugs, or radioisotopes may result in better therapeutic responses.« less

  19. Novel flow cytometric analysis of the progress and route of internalization of a monoclonal anti-carcinoembryonic antigen (CEA) antibody.

    PubMed

    Ford, C H; Tsaltas, G C; Osborne, P A; Addetia, K

    1996-03-01

    A flow cytometric method of studying the internalization of a monoclonal antibody (Mab) directed against carcinoembryonic antigen (CEA) has been compared with Western blotting, using three human colonic cancer cell lines which express varying amounts of the target antigen. Cell samples incubated for increasing time intervals with fluoresceinated or unlabelled Mab were analyzed using flow cytometry or polyacrylamide gel electrophoresis and Western blotting. SDS/PAGE analysis of cytosolic and membrane components of solubilized cells from the cell lines provided evidence of non-degraded internalized anti-CEA Mab throughout seven half hour intervals, starting at 5 min. Internalized anti-CEA was detected in the case of high CEA expressing cell lines (LS174T, SKCO1). Very similar results were obtained with an anti-fluorescein flow cytometric assay. Given that these two methods consistently provided comparable results, use of flow cytometry for the detection of internalized antibody is suggested as a rapid alternative to most currently used methods for assessing antibody internalization. The question of the endocytic route followed by CEA-anti-CEA complexes was addressed by using hypertonic medium to block clathrin mediated endocytosis.

  20. Could HER2 Heterogeneity Open New Therapeutic Options in Patients with HER2-Primary Breast Cancer

    DTIC Science & Technology

    2015-10-01

    purpose of this study is to determine if targeted imaging with a HER2 targeting PET tracer can detect HER2-positive metastases in patients with HER2... PET /CT. Two of five patients with suspicious foci had biopsy proven HER2-positive metastases. In this early stage clinical trial, 89 Zr-trastuzumab... PET /CT may detect HER2-positive metastases in patients with HER2-negtive primary breast cancer. This is an initial proof-of-concept that targeted

  1. Barriers to the Use of Trastuzumab for HER2+ Breast Cancer and the Potential Impact of Biosimilars: A Physician Survey in the United States and Emerging Markets.

    PubMed

    Lammers, Philip; Criscitiello, Carmen; Curigliano, Giuseppe; Jacobs, Ira

    2014-09-17

    Trastuzumab in combination with chemotherapy has become a standard of care for patients with HER2+ breast cancer. The cost of therapy, however, can limit patient access to trastuzumab in areas with limited financial resources for treatment reimbursement. This study examined access to trastuzumab and identified potential barriers to its use in the United States, Mexico, Turkey, Russia and Brazil via physician survey. The study also investigated if the availability of a biosimilar to trastuzumab would improve access to and use of HER2 monoclonal antibody therapy. Across all countries, a subset of oncologists reported barriers to the use of trastuzumab in a neoadjuvant, adjuvant or metastatic setting. Common barriers to the use of trastuzumab included issues related to insurance coverage, drug availability and cost to the patient. Overall, nearly half of oncologists reported that they would increase the use of HER2 monoclonal antibody therapy across all treatment settings if a lower cost biosimilar to trastuzumab were available. We conclude that the introduction of a biosimilar to trastuzumab may alleviate cost-related barriers to treatment and could increase patient access to HER2-directed therapy in all countries examined.

  2. Analysis of Monoclonal Antibodies in Human Serum as a Model for Clinical Monoclonal Gammopathy by Use of 21 Tesla FT-ICR Top-Down and Middle-Down MS/MS

    NASA Astrophysics Data System (ADS)

    He, Lidong; Anderson, Lissa C.; Barnidge, David R.; Murray, David L.; Hendrickson, Christopher L.; Marshall, Alan G.

    2017-05-01

    With the rapid growth of therapeutic monoclonal antibodies (mAbs), stringent quality control is needed to ensure clinical safety and efficacy. Monoclonal antibody primary sequence and post-translational modifications (PTM) are conventionally analyzed with labor-intensive, bottom-up tandem mass spectrometry (MS/MS), which is limited by incomplete peptide sequence coverage and introduction of artifacts during the lengthy analysis procedure. Here, we describe top-down and middle-down approaches with the advantages of fast sample preparation with minimal artifacts, ultrahigh mass accuracy, and extensive residue cleavages by use of 21 tesla FT-ICR MS/MS. The ultrahigh mass accuracy yields an RMS error of 0.2-0.4 ppm for antibody light chain, heavy chain, heavy chain Fc/2, and Fd subunits. The corresponding sequence coverages are 81%, 38%, 72%, and 65% with MS/MS RMS error 4 ppm. Extension to a monoclonal antibody in human serum as a monoclonal gammopathy model yielded 53% sequence coverage from two nano-LC MS/MS runs. A blind analysis of five therapeutic monoclonal antibodies at clinically relevant concentrations in human serum resulted in correct identification of all five antibodies. Nano-LC 21 T FT-ICR MS/MS provides nonpareil mass resolution, mass accuracy, and sequence coverage for mAbs, and sets a benchmark for MS/MS analysis of multiple mAbs in serum. This is the first time that extensive cleavages for both variable and constant regions have been achieved for mAbs in a human serum background.

  3. Trastuzumab uptake and its relation to efficacy in an animal model of HER2-positive breast cancer brain metastasis.

    PubMed

    Lewis Phillips, Gail D; Nishimura, Merry C; Lacap, Jennifer Arca; Kharbanda, Samir; Mai, Elaine; Tien, Janet; Malesky, Kimberly; Williams, Simon P; Marik, Jan; Phillips, Heidi S

    2017-08-01

    The extent to which efficacy of the HER2 antibody Trastuzumab in brain metastases is limited by access of antibody to brain lesions remains a question of significant clinical importance. We investigated the uptake and distribution of trastuzumab in brain and mammary fat pad grafts of HER2-positive breast cancer to evaluate the relationship of these parameters to the anti-tumor activity of trastuzumab and trastuzumab emtansine (T-DM1). Mouse transgenic breast tumor cells expressing human HER2 (Fo2-1282 or Fo5) were used to establish intracranial and orthotopic tumors. Tumor uptake and tissue distribution of systemically administered 89 Zr-trastuzumab or muMAb 4D5 (murine parent of trastuzumab) were measured by PET and ELISA. Efficacy of muMAb 4D5, the PI3K/mTOR inhibitor GNE-317, and T-DM1 was also assessed. 89 Zr-trastuzumab and muMAb 4D5 exhibited robust uptake into Fo2-1282 brain tumors, but not normal brains. Uptake into brain grafts was similar to mammary grafts. Despite this, muMAb 4D5 was less efficacious in brain grafts. Co-administration of muMAb 4D5 and GNE-317, a brain-penetrant PI3K/mTOR inhibitor, provided longer survival in mice with brain lesions than either agent alone. Moreover, T-DM1 increased survival in the Fo5 brain metastasis model. In models of HER2-positive breast cancer brain metastasis, trastuzumab efficacy does not appear to be limited by access to intracranial tumors. Anti-tumor activity improved with the addition of a brain-penetrant PI3K/mTOR inhibitor, suggesting that combining targeted therapies is a more effective strategy for treating HER2-positive breast cancer brain metastases. Survival was also extended in mice with Fo5 brain lesions treated with T-DM1.

  4. An antagonistic monoclonal antibody (B-N6) specific for the human neurotensin receptor-1.

    PubMed

    Ovigne, J M; Vermot-Desroches, C; Lecron, J C; Portier, M; Lupker, J; Pecceu, F; Wijdenes, J

    1998-06-01

    The neuropeptide neurotensin (NT) interacts with two types of human receptors (hNTR) termed hNTR-1 and hNTR-2. This study describes a monoclonal antibody (MAb) specific for hNTR-1, B-N6. This MAb binds specifically to hNTR-1, but not to hNTR-2 transfected CHO cells. B-N6 and NT display a reciprocal competition and react in a similar way to trypsin, suggesting that the B-N6 epitope is at or close to the NT binding site on the third extracellular loop. Unlike B-N6, NT induces hNTR-1 internalization. Although neither NT-FITC nor B-N6 binding was detected by flow cytometry on different human cells, specific mRNA expression for hNTR-1 was detected in these cells. In CHO cells expressing hNTR-1 and a luciferase gene coupled to the krox24 reporter, B-N6 and the antagonist SR 48692 inhibited NT-induced intracellular activation of krox24 in a dose-dependent manner. From these results it is concluded that B-N6 is an antagonistic anti-hNTR-1 MAb.

  5. Generation and characterization of a potent fully human monoclonal antibody against the interleukin-23 receptor.

    PubMed

    Sasaki-Iwaoka, Haruna; Ohori, Makoto; Imasato, Akira; Taguchi, Katsunari; Minoura, Kyoko; Saito, Tetsu; Kushima, Kiyoshi; Imamura, Emiko; Kubo, Satoshi; Furukawa, Shigetada; Morokata, Tatsuaki

    2018-06-05

    Interleukin (IL)-12 and IL-23 share a common subunit (p40) and function in T-helper (Th) 1 and Th17 immunity, respectively. Anti-IL-12/23p40 and specific anti-IL-23 antibodies are currently in clinical use for psoriasis and undergoing trials for autoimmune diseases. Since expression levels of the IL-23 receptor are likely to be much lower than those of IL-23, an anti-IL-23 receptor antibody might offer greater promise in inhibiting the IL-23-IL-17 pathways involved in inflammatory disorders. To our knowledge, no anti-IL-23 receptor antibody has been trialed in clinical studies to date. This study describes the generation and characterization of AS2762900-00, a fully human monoclonal antibody against the IL-23 receptor. AS2762900-00 bound both human and cynomolgus monkey IL-23 receptors. AS2762900-00 showed potent inhibitory effects on IL-23-induced Kit-225 cell proliferation compared to the existing anti-IL-12/23p40 antibody, ustekinumab. In a single dose administration pharmacodynamics study in cynomolgus monkeys, 1 mg/kg of AS2762900-00 significantly inhibited (> 85%) IL-23-induced STAT3 phosphorylation in blood for up to 84 days. Therefore, AS2762900-00 represents a potent novel IL-23-IL-17 pathway inhibitor with the potential to be developed into a new therapy for the treatment of autoimmune diseases. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Genetic heterogeneity and actionable mutations in HER2-positive primary breast cancers and their brain metastases.

    PubMed

    De Mattos-Arruda, Leticia; Ng, Charlotte K Y; Piscuoglio, Salvatore; Gonzalez-Cao, Maria; Lim, Raymond S; De Filippo, Maria R; Fusco, Nicola; Schultheis, Anne M; Ortiz, Carolina; Viteri, Santiago; Arias, Alexandra; Macedo, Gabriel S; Oliveira, Mafalda; Gomez, Patricia; Teixidó, Cristina; Nuciforo, Paolo; Peg, Vicente; Saura, Cristina; Ramon Y Cajal, Santiago; Casas, Francesc Tresserra; Weigelt, Britta; Cortes, Javier; Seoane, Joan; Reis-Filho, Jorge S

    2018-04-17

    Brain metastases constitute a challenge in the management of patients with HER2-positive breast cancer treated with anti-HER2 systemic therapies. Here we sought to define the repertoire of mutations private to or enriched for in HER2-positive brain metastases. Massively parallel sequencing targeting all exons of 254 genes frequently mutated in breast cancers and/or related to DNA repair was used to characterize the spatial and temporal heterogeneity of HER2-positive breast cancers and their brain metastases in six patients. Data were analyzed with state-of-the-art bioinformatics algorithms and selected mutations were validated with orthogonal methods. Spatial and temporal inter-lesion genetic heterogeneity was observed in the HER2-positive brain metastases from an index patient subjected to a rapid autopsy. Genetic alterations restricted to the brain metastases included mutations in cancer genes FGFR2, PIK3CA and ATR , homozygous deletion in CDKN2A and amplification in KRAS . Shifts in clonal composition and the acquisition of additional mutations in the progression from primary HER2-positive breast cancer to brain metastases following anti-HER2 therapy were investigated in additional five patients. Likely pathogenic mutations private to or enriched in the brain lesions affected cancer and clinically actionable genes, including ATR, BRAF, FGFR2, MAP2K4, PIK3CA, RAF1 and TP53 . Changes in clonal composition and the acquisition of additional mutations in brain metastases may affect potentially actionable genes in HER2-positive breast cancers. Our observations have potential clinical implications, given that treatment decisions for patients with brain metastatic disease are still mainly based on biomarkers assessed in the primary tumor.

  7. CCR2-V64I genetic polymorphism: a possible involvement in HER2+ breast cancer.

    PubMed

    Banin-Hirata, Bruna Karina; Losi-Guembarovski, Roberta; Oda, Julie Massayo Maeda; de Oliveira, Carlos Eduardo Coral; Campos, Clodoaldo Zago; Mazzuco, Tânia Longo; Borelli, Sueli Donizete; Ceribelli, Jesus Roberto; Watanabe, Maria Angelica Ehara

    2016-05-01

    Many tumor cells express chemokines and chemokine receptors, and these molecules can affect both tumor progression and anti-tumor immune response. Genetic polymorphisms of some chemokine receptors were found to be closely related to malignant tumors, especially in metastasis process, including breast cancer (BC). Considering this, it was investigated a possible role for CCR2-V64I (C-C chemokine receptor 2) and CCR5-Δ32 (C-C chemokine receptor 5) genetic variants in BC context. Patients were divided into subgroups according to immunohistochemical profile of estrogen (ER) and progesterone (PR) receptors and the human epidermal growth factor receptor 2 (HER2) overexpression. No significant associations were found in relation to susceptibility (CCR2-V64I: OR 1.32; 95 % CI 0.57-3.06; CCR5-∆32: OR 1.04; 95 % CI 0.60-1.81), clinical outcome (tumor size, lymph nodes commitment and/or distant metastasis, TNM staging and nuclear grade) or therapeutic response (recurrence and survival). However, it was found a significant correlation between CCR2-V64I allelic variant and HER2 immunohistochemical positive samples (p = 0.026). All in all, we demonstrate, for the first time, a positive correlation between CCR2 receptor gene polymorphism and a subgroup of BC related to poor prognosis, which deserves further investigation in larger samples for validation.

  8. Platelet receptors for the Streptococcus sanguis adhesin and aggregation-associated antigens are distinguished by anti-idiotypical monoclonal antibodies.

    PubMed Central

    Gong, K; Wen, D Y; Ouyang, T; Rao, A T; Herzberg, M C

    1995-01-01

    Platelets aggregate in response to an adhesin and the platelet aggregation-associated protein (PAAP) expressed on the cell surfaces of certain strains of Streptococcus sanguis. We sought to identify the corresponding PAAP receptor and accessory adhesin binding sites on platelets. Since the adhesion(s) of S. sanguis for platelets has not been characterized, an anti-idiotype (anti-id) murine monoclonal antibody (MAb2) strategy was developed. First, MAb1s that distinguished the adhesin and PAAP antigens on the surface of S. sanguis I 133-79 were selected. Fab fragments of MAb1.2 (immunoglobulin G2b [IgG2b]; 70 pmol) reacted with 5 x 10(7) cells of S. sanguis to completely inhibit the aggregation of human platelets in plasma. Under similar conditions, MAb1.1 (IgG1) inhibited the adhesion of S. sanguis cells to platelets by a maximum of 34%, with a comparatively small effect on platelet aggregation. Together, these two MAb1s inhibited S. sanguis-platelet adhesion by 63%. In Western immunoblots, both MAb1s reacted with S. sanguis 133-79 87- and 150-kDa surface proteins and MAb1.2 also reacted with purified type I collagen. The hybridomas producing MAb1.1 and MAb1.2 were then injected into BALB/c mice. Enlarged spleens were harvested, and a panel of MAb2 hybridomas was prepared. To identify anti-ids against the specific MAb1s, the MAb2 panel was screened by enzyme-linked immunosorbent assay for reaction with rabbit polyclonal IgG antibodies against the 87- and 150-kDa antigens. The reactions between the specific rabbit antibodies and anti-ids were inhibited by the 87- and 150-kDa antigens. When preincubated with platelets, MAb2.1 (counterpart of MAb1.1) inhibited adhesion to platelets maximally by 46% and MAb2.2 (anti-MAb1.2) inhibited adhesion to platelets maximally by 35%. Together, both MAb2s inhibited the adhesion of S. sanguis to platelets by 81%. MAb2.2 also inhibited induction of platelet aggregation. MAb2.2 immunoprecipitated a biotinylated platelet membrane

  9. The Impact of Concomitant Genomic Alterations on Treatment Outcome for Trastuzumab Therapy in HER2-Positive Gastric Cancer

    PubMed Central

    Lee, Ji Yun; Hong, Mineui; Kim, Seung Tae; Park, Se Hoon; Kang, Won Ki; Kim, Kyoung-Mee; Lee, Jeeyun

    2015-01-01

    Clinical benefit from trastuzumab and other anti-human epidermal growth factor receptor-2 (HER2) therapies in patients with HER2-positive gastric cancer (GC) remains limited by primary or acquired resistance. We aimed to investigate the impact of concomitant molecular alterations to HER2 amplification on the clinical outcome of trastuzumab-treated patients. Using immunohistochemistry (IHC), copy number variations (CNVs), and Ion Ampliseq Cancer Panel, we analyzed the status of concomitant alterations in 50 HER2-positive advanced GC patients treated with trastuzumab in combination with other chemotherapeutic agents. The percentage of tumor samples with at least one concomitant alteration was 40% as assessed by IHC, 16% by CNVs, and 64% by Ampliseq sequencing. Median progression-free survival (PFS) was 8.0 months (95% confidence interval, 4.8–11.3). Patients were divided into two subgroups according to PFS values with a cutoff point of 8 months; results show that concomitant genomic alterations do not correlate with trastuzumab response. However, CNVs of CCNE1 significantly correlated (p < 0.05) with a shorter survival time. Our findings indicate that additional alterations implemented for prediction of clinical benefit from HER2-targeting agents in GC remained unclear. Further studies will be needed to elucidate the role of each specific biomarker and to optimize therapeutic approaches. PMID:25786580

  10. Neratinib, A Novel HER2-Targeted Tyrosine Kinase Inhibitor.

    PubMed

    Tiwari, Shruti Rakesh; Mishra, Prasun; Abraham, Jame

    2016-10-01

    HER2 gene amplification and receptor overexpression is identified in 20% to 25% of human breast cancers. Use of targeted therapy for HER2-amplified breast cancer has led to improvements in disease-free and overall survival in this subset of patients. Neratinib is an oral pan HER inhibitor, that irreversibly inhibits the tyrosine kinase activity of epidermal growth factor receptor (EGFR or HER1), HER2, and HER4, which leads to reduced phosphorylation and activation of downstream signaling pathways. Neratinib is currently being tested in a number of clinical trials for its safety and efficacy in lung cancer, and colorectal, bladder, and breast cancers. In this review we discuss the available phase I, II, and III data for use of neratinib in the metastatic, adjuvant, neoadjuvant, and extended adjuvant settings along with the ongoing clinical trials of neratinib in breast cancer. We also elaborate on the side effect profile of this relatively new drug and provide guidelines for its use in clinical practice. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Establishment and characterization of monoclonal and polyclonal antibodies against human intestinal fatty acid-binding protein (I-FABP) using synthetic regional peptides and recombinant I-FABP.

    PubMed

    Kajiura, Satoshi; Yashiki, Tetsuya; Funaoka, Hiroyuki; Ohkaru, Yasuhiko; Nishikura, Ken; Kanda, Tatsuo; Ajioka, Yoichi; Igarashi, Michihiro; Hatakeyama, Katsuyoshi; Fujii, Hiroshi

    2008-01-01

    We have succeeded in raising highly specific anti-human intestinal fatty acid-binding protein (I-FABP) monoclonal antibodies by immunizing animals with three synthetic regional peptides, i.e., the amino terminal (RP-1: N-acetylated 1-19-cysteine), middle portion (RP-2: cysteinyl-91-107) and carboxylic terminal (RP-3: cysteinyl-121-131) regions of human I-FABP, and the whole I-FABP molecule as antigens. We also raised a polyclonal antibody by immunizing with a recombinant (r) I-FABP. To ascertain the specificity of these antibodies for human I-FABP, the immunological reactivity of each was examined by a binding assay using rI-FABP, partially purified native I-FABP and related proteins such as liver-type (L)-FABP, heart-type (H)-FABP, as well as the regional peptides as reactants, and by Western blot analysis. In addition, the expression and distribution of I-FABP in the human gastrointestinal tract were investigated by an immunohistochemical technique using a carboxylic terminal region-specific monoclonal antibody, 8F9, and a polyclonal antibody, DN-R2. Our results indicated that both the monoclonal and polyclonal antibodies established in this study were highly specific for I-FABP, but not for L-FABP and H-FABP. Especially, the monoclonal antibodies raised against the regional peptides, showed regional specificity for the I-FABP molecule. Immunoreactivity of I-FABP was demonstrated in the mucosal epithelium of the jejunum and ileum by immunohistochemical staining, and the immunoreactivity was based on the presence of the whole I-FABP molecule but not the presence of any precursors or degradation products containing a carboxylic terminal fragment. It is concluded that some of these monoclonal and polyclonal antibodies, such as 8F9, 4205, and DN-R2, will be suitable for use in research on the immunochemistry and clinical chemistry of I-FABP because those antibodies can recognize both types of native and denatured I-FABP. In order to detect I-FABP in blood samples, it

  12. Photoluminescence detection of 2,4,6-trinitrotoluene (TNT) binding on diatom frustule biosilica functionalized with an anti-TNT monoclonal antibody fragment.

    PubMed

    Zhen, Le; Ford, Nicole; Gale, Debra K; Roesijadi, Guritno; Rorrer, Gregory L

    2016-05-15

    A selective and label-free biosensor for detection of the explosive compound 2,4,6-trinitrotoluene (TNT) in aqueous solution was developed based on the principle of photoluminescence quenching of upon immunocomplex formation with antibody-functionalized diatom frustule biosilica. The diatom frustule is an intricately nanostructured, highly porous biogenic silica material derived from the shells of microscopic algae called diatoms. This material emits strong visible blue photoluminescence (PL) upon UV excitation. PL-active frustule biosilica was isolated from cultured cells of the marine diatom Pinnularia sp. and functionalized with a single chain variable fragment (scFv) derived from an anti-TNT monoclonal antibody. When TNT was bound to the anti-TNT scFv-functionalized diatom frustule biosilica, the PL emission from the biosilica was partially quenched due to the electrophilic nature of the nitro (-NO2) groups on the TNT molecule. The dose-response curve for immunocomplex formation of TNT on the scFv-functionalized diatom frustule biosilica had a half-saturation binding constant of 6.4 ± 2.4·10(-8)M and statistically-significant measured detection limit of 3.5·10(-8)M. The binding and detection were selective for TNT and TNB (trinitrobenzene) but not RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) or 2,6-DNT (2,6-dinitrotoluene). Copyright © 2016. Published by Elsevier B.V.

  13. A HER2-targeting antibody-drug conjugate, trastuzumab deruxtecan (DS-8201a), enhances antitumor immunity in a mouse model.

    PubMed

    Iwata, Tomomi Nakayama; Ishii, Chiaki; Ishida, Saori; Ogitani, Yusuke; Wada, Teiji; Agatsuma, Toshinori

    2018-04-27

    Trastuzumab deruxtecan (DS-8201a), a HER2-targeting antibody-drug conjugate with a topoisomerase I inhibitor exatecan derivative (DX-8951 derivative, DXd), has been reported to exert potent antitumor effects in xenograft mouse models and clinical trials. In this study, the immune system-activating ability of DS-8201a was assessed. DS-8201a significantly suppressed tumor growth in an immunocompetent mouse model with human HER2-expressing CT26.WT (CT26.WT-hHER2) cells. Cured immunocompetent mice rejected not only re-challenged CT26.WT-hHER2 cells, but also CT26.WT-mock cells. Splenocytes from the cured mice responded to both CT26.WT-hHER2 and CT26.WT-mock cells. Further analyses revealed that DXd up-regulated CD86 expression on bone marrow-derived DCs in vitro, and that DS-8201a increased tumor-infiltrating DCs and up-regulated their CD86 expression in vivo. DS-8201a also increased tumor-infiltrating CD8+ T cells and enhanced PD-L1 and MHC class I expression on tumor cells. Furthermore, combination therapy with DS-8201a and anti-PD-1 antibody was more effective than either monotherapy. In conclusion, DS-8201a enhanced antitumor immunity, as evidenced by the increased expression of DC markers, augmented expression of MHC class I in tumor cells, and rejection of re-challenged tumor cells by adaptive immune cells, suggesting that DS-8201a enhanced tumor recognition by T cells. Furthermore, DS-8201a treatment benefited from combination with anti-PD-1 antibody, possibly due to increased T cell activity and up-regulated PD-L1 expression induced by DS-8201a. Copyright ©2018, American Association for Cancer Research.

  14. Seroepidemiology of Human Papillomavirus 16 (HPV16) L2 and Generation of L2-Specific Human Chimeric Monoclonal Antibodies

    PubMed Central

    Wang, Joshua W.; Jagu, Subhashini; Wu, Wai-Hong; Viscidi, Raphael P.; Macgregor-Das, Anne; Fogel, Jessica M.; Kwak, Kihyuck; Daayana, Sai; Kitchener, Henry; Stern, Peter L.; Gravitt, Patti E.; Trimble, Cornelia L.

    2015-01-01

    Presently, the seroprevalence of human papillomavirus (HPV) minor capsid antigen L2-reactive antibody is not well understood, and no serologic standard exists for L2-specific neutralizing antibodies. Therefore, we screened a total of 1,078 serum samples for HPV16 L2 reactivity, and these were obtained from four prior clinical studies: a population-based (n = 880) surveillance study with a high-risk HPV DNA prevalence of 10.8%, a cohort study of women (n = 160) with high-grade cervical intraepithelial neoplasia (CIN), and two phase II trials in women with high-grade vulvar intraepithelial neoplasia (VIN) receiving imiquimod therapy combined with either photodynamic therapy (PDT) (n = 19) or vaccination with a fusion protein comprising HPV16 L2, E7, and E6 (TA-CIN) (n = 19). Sera were screened sequentially by HPV16 L2 enzyme-linked immunosorbent assay (ELISA) and then Western blot. Seven of the 1,078 serum samples tested had L2-specific antibodies, but none were detectably neutralizing for HPV16. To develop a standard, we substituted human IgG1 sequences into conserved regions of two rodent monoclonal antibodies (MAbs) specific for neutralizing epitopes at HPV16 L2 residues 17 to 36 and 58 to 64, creating JWW-1 and JWW-2, respectively. These chimeric MAbs retained neutralizing activity and together reacted with 33/34 clinically relevant HPV types tested. In conclusion, our inability to identify an HPV16 L2-specific neutralizing antibody response even in the sera of patients with active genital HPV disease suggests the subdominance of L2 protective epitopes and the value of the chimeric MAbs JWW-1 and JWW-2 as standards for immunoassays to measure L2-specific human antibodies. PMID:25972404

  15. Comparison of central HER2 testing with quantitative total HER2 expression and HER2 homodimer measurements using a novel proximity-based assay.

    PubMed

    Huang, Weidong; Reinholz, Monica; Weidler, Jodi; Yolanda, Lie; Paquet, Agnes; Whitcomb, Jeannette; Lingle, Wilma; Jenkins, Robert B; Chen, Beiyun; Larson, Jeffrey S; Tan, Yuping; Sherwood, Thomas; Bates, Michael; Perez, Edith A

    2010-08-01

    The accuracy and reliability of immunohistochemical analysis and in situ hybridization for the assessment of HER2 status remains a subject of debate. We developed a novel assay (HERmark Breast Cancer Assay, Monogram Biosciences, South San Francisco, CA) that provides precise quantification of total HER2 protein expression (H2T) and HER2 homodimers (H2D) in formalin-fixed, paraffin-embedded tissue specimens. H2T and H2D results of 237 breast cancers were compared with those of immunohistochemical studies and fluorescence in situ hybridization (FISH) centrally performed at the Mayo Clinic, Rochester, MN. H2T described a continuum across a wide dynamic range ( approximately 2.5 log). Excluding the equivocal cases, HERmark showed 98% concordance with immunohistochemical studies for positive and negative assay values. For the 94 immunohistochemically equivocal cases, 67% and 39% concordance values were observed between HERmark and FISH for positive and negative assay values, respectively. Polysomy 17 in the absence of HER2 gene amplification did not result in HER2 overexpression as evaluated quantitatively using the HERmark assay.

  16. High p95HER2/HER2 Ratio Associated With Poor Outcome in Trastuzumab-Treated HER2-Positive Metastatic Breast Cancer NCCTG N0337 and NCCTG 98-32-52 (Alliance).

    PubMed

    Chumsri, Saranya; Sperinde, Jeff; Liu, Heshan; Gligorov, Joseph; Spano, Jean-Philippe; Antoine, Martine; Moreno Aspitia, Alvaro; Tan, Winston; Winslow, John; Petropoulos, Christos J; Chenna, Ahmed; Bates, Michael; Weidler, Jodi Marie; Huang, Weidong; Dueck, Amylou; Perez, Edith A

    2018-03-12

    Purpose: p95HER2 is a truncated form of HER2 that confers resistance to trastuzumab in vitro , but clinical results have been conflicting to date. Given that p95HER2 levels correlate with total HER2 expression levels, which confer better outcomes, we sought to evaluate the p95HER2/HER2 ratio in the North Central Cancer Treatment Group N0337 and N98-32-52 trials. Experimental Design: The HERmark assay and VeraTag technology (Monogram Biosciences) were used to measure total HER2 and p95HER2 expression levels in 91 patient samples. Results: In the multivariate model, increasing total HER2 level was significantly associated with longer (OS; HR, 0.33; P = 0.002) and decreasing p95HER2 level was significantly associated with longer OS (HR, 4.2; P = 0.01). Total HER2 expression level was significantly associated with longer progression-free survival (PFS) (HR, 0.57; P = 0.04), whereas p95HER2 level was not (HR, 1.7; P = 0.25). However, there was a positive association between p95HER2 and total HER2 expression levels ( R 2 = 0.48; P < 0.001). Consistent with our hypothesis, the ratio of p95HER2/HER2 was significantly associated with worsening PFS (HR, 1.7; P = 0.04) and OS (HR, 2.8; P = 0.002). Patients with the highest tertile of p95HER2/HER2 values had significantly less favorable PFS (HR, 1.8; P = 0.06) and OS (HR, 2.3; P = 0.02). Conclusions: A high p95HER2/HER2 ratio identified patients with metastatic breast cancer with poor outcomes on trastuzumab-based therapies. Further investigation of the p95HER2/HER2 ratio as a potential prognostic or predictive biomarker for HER2-targeted therapy is warranted. Clin Cancer Res; 1-6. ©2018 AACR. ©2018 American Association for Cancer Research.

  17. The Role of Anti-Drug Antibodies in the Pharmacokinetics, Disposition, Target Engagement, and Efficacy of a GITR Agonist Monoclonal Antibody in Mice.

    PubMed

    Brunn, Nicholas D; Mauze, Smita; Gu, Danling; Wiswell, Derek; Ueda, Roanna; Hodges, Douglas; Beebe, Amy M; Zhang, Shuli; Escandón, Enrique

    2016-03-01

    Administration of biologics to enhance T-cell function is part of a rapidly growing field of cancer immunotherapy demonstrated by the unprecedented clinical success of several immunoregulatory receptor targeting antibodies. While these biologic agents confer significant anti-tumor activity through targeted immune response modulation, they can also elicit broad immune responses potentially including the production of anti-drug antibodies (ADAs). DTA-1, an agonist monoclonal antibody against GITR, is a highly effective anti-tumor treatment in preclinical models. We demonstrate that repeated dosing with murinized DTA-1 (mDTA-1) generates ADAs with corresponding reductions in drug exposure and engagement of GITR on circulating CD3(+) CD4(+) T cells, due to rapid hepatic drug uptake and catabolism. Mice implanted with tumors after induction of preexisting mDTA-1 ADA show no anti-tumor efficacy when given 3 mg/kg mDTA-1, an efficacious dose in naive mice. Nonetheless, increasing mDTA-1 treatment to 30 mg/kg in ADA-positive mice restores mDTA-1 exposure and GITR engagement on circulating CD3(+) CD4(+) T cells, thereby partially restoring anti-tumor efficacy. Formation of anti-mDTA-1 antibodies and changes in drug exposure and disposition does not occur in GITR(-/-) mice, consistent with a role for GITR agonism in humoral immunity. Finally, the administration of muDX400, a murinized monoclonal antibody against the checkpoint inhibitor PD-1, dosed alone or combined with mDTA-1 did not result in reduced muDX400 exposure, nor did it change the nature of the anti-mDTA-1 response. This indicates that anti-GITR immunogenicity may not necessarily impact the pharmacology of coadministered monoclonal antibodies, supporting combination immunomodulatory strategies. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  18. Could HER2 Heterogeneity Open New Therapeutic Options in Patients with HER2-Primary Breast Cancer

    DTIC Science & Technology

    2016-10-01

    AWARD NUMBER: W81XWH-14-1-0444 TITLE: Could HER2 Heterogeneity Open New Therapeutic Options in Patients with HER2- Primary Breast Cancer...Prescribed by ANSI Std. Z39.18 Could HER2 Heterogeneity Open New Therapeutic Options in Patients with HER2- Primary Breast Cancer? 30 Sep 2015 - 29 Sep...Financial Report Ulaner, Gary PROGRESS REPORT: October 2016 DoD W81XWH-14-1-0444 Could HER2 heterogeneity open new therapeutic options in patients with

  19. Characterization of anti-CD20 monoclonal antibody produced by transgenic silkworms (Bombyx mori).

    PubMed

    Tada, Minoru; Tatematsu, Ken-ichiro; Ishii-Watabe, Akiko; Harazono, Akira; Takakura, Daisuke; Hashii, Noritaka; Sezutsu, Hideki; Kawasaki, Nana

    2015-01-01

    In response to the successful use of monoclonal antibodies (mAbs) in the treatment of various diseases, systems for expressing recombinant mAbs using transgenic animals or plants have been widely developed. The silkworm (Bombyx mori) is a highly domesticated insect that has recently been used for the production of recombinant proteins. Because of their cost-effective breeding and relatively easy production scale-up, transgenic silkworms show great promise as a novel production system for mAbs. In this study, we established a transgenic silkworm stably expressing a human-mouse chimeric anti-CD20 mAb having the same amino acid sequence as rituximab, and compared its characteristics with rituximab produced by Chinese hamster ovary (CHO) cells (MabThera®). The anti-CD20 mAb produced in the transgenic silkworm showed a similar antigen-binding property, but stronger antibody-dependent cell-mediated cytotoxicity (ADCC) and weaker complement-dependent cytotoxicity (CDC) compared to MabThera. Post-translational modification analysis was performed by peptide mapping using liquid chromatography/mass spectrometry. There was a significant difference in the N-glycosylation profile between the CHO- and the silkworm-derived mAbs, but not in other post-translational modifications including oxidation and deamidation. The mass spectra of the N-glycosylated peptide revealed that the observed biological properties were attributable to the characteristic N-glycan structures of the anti-CD20 mAbs produced in the transgenic silkworms, i.e., the lack of the core-fucose and galactose at the non-reducing terminal. These results suggest that the transgenic silkworm may be a promising expression system for the tumor-targeting mAbs with higher ADCC activity.

  20. HER2 expression identifies dynamic functional states within circulating breast cancer cells.

    PubMed

    Jordan, Nicole Vincent; Bardia, Aditya; Wittner, Ben S; Benes, Cyril; Ligorio, Matteo; Zheng, Yu; Yu, Min; Sundaresan, Tilak K; Licausi, Joseph A; Desai, Rushil; O'Keefe, Ryan M; Ebright, Richard Y; Boukhali, Myriam; Sil, Srinjoy; Onozato, Maristela L; Iafrate, Anthony J; Kapur, Ravi; Sgroi, Dennis; Ting, David T; Toner, Mehmet; Ramaswamy, Sridhar; Haas, Wilhelm; Maheswaran, Shyamala; Haber, Daniel A

    2016-09-01

    Circulating tumour cells in women with advanced oestrogen-receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer acquire a HER2-positive subpopulation after multiple courses of therapy. In contrast to HER2-amplified primary breast cancer, which is highly sensitive to HER2-targeted therapy, the clinical significance of acquired HER2 heterogeneity during the evolution of metastatic breast cancer is unknown. Here we analyse circulating tumour cells from 19 women with ER + /HER2 - primary tumours, 84% of whom had acquired circulating tumour cells expressing HER2. Cultured circulating tumour cells maintain discrete HER2 + and HER2 - subpopulations: HER2 + circulating tumour cells are more proliferative but not addicted to HER2, consistent with activation of multiple signalling pathways; HER2 - circulating tumour cells show activation of Notch and DNA damage pathways, exhibiting resistance to cytotoxic chemotherapy, but sensitivity to Notch inhibition. HER2 + and HER2 - circulating tumour cells interconvert spontaneously, with cells of one phenotype producing daughters of the opposite within four cell doublings. Although HER2 + and HER2 - circulating tumour cells have comparable tumour initiating potential, differential proliferation favours the HER2 + state, while oxidative stress or cytotoxic chemotherapy enhances transition to the HER2 - phenotype. Simultaneous treatment with paclitaxel and Notch inhibitors achieves sustained suppression of tumorigenesis in orthotopic circulating tumour cell-derived tumour models. Together, these results point to distinct yet interconverting phenotypes within patient-derived circulating tumour cells, contributing to progression of breast cancer and acquisition of drug resistance.

  1. Single-Molecule Interactions of a Monoclonal Anti-DNA Antibody with DNA

    PubMed Central

    Nevzorova, Tatiana A.; Zhao, Qingze; Lomakin, Yakov A.; Ponomareva, Anastasia A.; Mukhitov, Alexander R.; Purohit, Prashant K.; Weisel, John W.; Litvinov, Rustem I.

    2017-01-01

    Interactions of DNA with proteins are essential for key biological processes and have both a fundamental and practical significance. In particular, DNA binding to anti-DNA antibodies is a pathogenic mechanism in autoimmune pathology, such as systemic lupus erythematosus. Here we measured at the single-molecule level binding and forced unbinding of surface-attached DNA and a monoclonal anti-DNA antibody MRL4 from a lupus erythematosus mouse. In optical trap-based force spectroscopy, a microscopic antibodycoated latex bead is trapped by a focused laser beam and repeatedly brought into contact with a DNA-coated surface. After careful discrimination of non-specific interactions, we showed that the DNA-antibody rupture force spectra had two regimes, reflecting formation of weaker (20–40 pN) and stronger (>40 pN) immune complexes that implies the existence of at least two bound states with different mechanical stability. The two-dimensional force-free off-rate for the DNA-antibody complexes was ~2.2 × 10−3 s−1, the transition state distance was ~0.94 nm, the apparent on-rate was ~5.26 s−1, and the stiffness of the DNA-antibody complex was characterized by a spring constant of 0.0021 pN/nm, suggesting that the DNA-antibody complex is a relatively stable, but soft and deformable macromolecular structure. The stretching elasticity of the DNA molecules was characteristic of single-stranded DNA, suggesting preferential binding of the MRL4 antibody to one strand of DNA. Collectively, the results provide fundamental characteristics of formation and forced dissociation of DNA-antibody complexes that help to understand principles of DNA-protein interactions and shed light on the molecular basis of autoimmune diseases accompanied by formation of anti-DNA antibodies. PMID:29104846

  2. The level of HER2 expression is a predictor of antibody-HER2 trafficking behavior in cancer cells

    PubMed Central

    Ram, Sripad; Kim, Dongyoung; Ober, Raimund J; Ward, E Sally

    2014-01-01

    The receptor tyrosine kinase HER2 is known to play a central role in mitogenic signaling, motivating the development of targeted, HER2-specific therapies. However, despite the longstanding use of antibodies to target HER2, controversies remain concerning antibody/HER2 trafficking behavior in cancer cells. Understanding this behavior has direct relevance to the mechanism of action and effective design of such antibodies. In the current study, we analyzed the intracellular dynamics of trastuzumab, a marketed HER2-targeting antibody, in a panel of breast and prostate cancer cell lines that have a wide range of HER2 expression levels. Our results reveal distinct post-endocytic trafficking behavior of antibody-HER2 complexes in cells with different HER2 expression levels. In particular, HER2-overexpressing cells exhibit efficient HER2 recycling and limited reductions in HER2 levels upon antibody treatment, and consequently display a high level of antibody persistence on their plasma membrane. By contrast, in cells with low HER2 expression, trastuzumab treatment results in rapid antibody clearance from the plasma membrane combined with substantial decreases in HER2 levels and undetectable levels of recycling. A cell line with intermediate levels of HER2 expression exhibits both antibody recycling and clearance from the cell surface. Significantly, these analyses demonstrate that HER2 expression levels, rather than cell origin (breast or prostate), is a determinant of subcellular trafficking properties. Such studies have relevance to optimizing the design of antibodies to target HER2. PMID:25517306

  3. Boron Neutron Capture Therapy for HER2+ breast cancers: A feasibility study evaluating BNCT for potential role in breast conservation therapies

    NASA Astrophysics Data System (ADS)

    Jenkins, Peter Anthony

    A novel Boron Neutron Capture Therapy (BNCT) regimen for the treatment of HER2+ breast cancers has been proposed as an alternative to whole breast irradiation for breast conservation therapy patients. The proposed therapy regimen is based on the assumed production of boron delivery agents that would be synthesized from compounds of Trastuzumab (Herceptin ®) and oligomeric phosphate diesters (OPDs). The combination of the anti-HER2 monoclonal antibody and the high boron loading capability of OPDs has led to the assumption that boron could be delivered to the HER2+ cancer cells at Tumor to Healthy Tissue ratios (T:H) of up to 35:1 and boron concentrations above 50 μg/g. This significantly increased boron delivery efficiency has opened new BNCT possibilities. This proof of concept study examined treatment parameters derived as the results in previous efforts in the context of patient-specific geometry and compared calculated dose results to those observed during actual patient therapy. These results were based on dose calculations performed with a set of calculated Kerma coefficients derived from tissues specific to the regions of interest for breast cancer. A comparison was made of the dose to the tumor region, the patient's skin, and the peripheral organs. The results of this study demonstrated that, given the performance of the proposed boron delivery agent, the BNCT treatment regimen is feasible. The feasibility is based on the findings that the equivalent dose could be delivered to the treatment volume with less dose to the skin and peripheral organs. This is anticipated to improve the treatment outcomes by maintaining local control of tumor cells while reducing dose to healthy tissues.

  4. Computational Prediction of Neutralization Epitopes Targeted by Human Anti-V3 HIV Monoclonal Antibodies

    PubMed Central

    Shmelkov, Evgeny; Krachmarov, Chavdar; Grigoryan, Arsen V.; Pinter, Abraham; Statnikov, Alexander; Cardozo, Timothy

    2014-01-01

    The extreme diversity of HIV-1 strains presents a formidable challenge for HIV-1 vaccine design. Although antibodies (Abs) can neutralize HIV-1 and potentially protect against infection, antibodies that target the immunogenic viral surface protein gp120 have widely variable and poorly predictable cross-strain reactivity. Here, we developed a novel computational approach, the Method of Dynamic Epitopes, for identification of neutralization epitopes targeted by anti-HIV-1 monoclonal antibodies (mAbs). Our data demonstrate that this approach, based purely on calculated energetics and 3D structural information, accurately predicts the presence of neutralization epitopes targeted by V3-specific mAbs 2219 and 447-52D in any HIV-1 strain. The method was used to calculate the range of conservation of these specific epitopes across all circulating HIV-1 viruses. Accurately identifying an Ab-targeted neutralization epitope in a virus by computational means enables easy prediction of the breadth of reactivity of specific mAbs across the diversity of thousands of different circulating HIV-1 variants and facilitates rational design and selection of immunogens mimicking specific mAb-targeted epitopes in a multivalent HIV-1 vaccine. The defined epitopes can also be used for the purpose of epitope-specific analyses of breakthrough sequences recorded in vaccine clinical trials. Thus, our study is a prototype for a valuable tool for rational HIV-1 vaccine design. PMID:24587168

  5. Detection and quantitation of HER-2/neu gene amplification in human breast cancer archival material using fluorescence in situ hybridization.

    PubMed

    Pauletti, G; Godolphin, W; Press, M F; Slamon, D J

    1996-07-04

    Amplification and overexpression of the HER-2/neu gene occurs in 25-30% of human breast cancers. This genetic alteration is associated with a poor clinical prognosis in women with either node negative or node positive breast cancers. The initial studies testing this association were somewhat controversial and this controversy was due in large part to significant heterogeneity in both the methods and/or reagents used in testing archival material for the presence of the alteration. These methods included a number of solid matrix blotting techniques for DNA, RNA and protein as well as immunohistochemistry. Fluorescence in situ hybridization (FISH) represents the newest methodologic approach for testing for this genetic alteration. In this study, FISH is compared to Southern, Northern and Western blot analyses as well as immunohistochemistry in a large cohort of archival human breast cancer specimens. FISH was found to be superior to all other methodologies tested in assessing formalin fixed, paraffin embedded material for HER-2/neu amplification. The results from this study also confirm that overexpression of HER-2/neu rarely occurs in the absence of gene amplification in breast cancer (approximately 3% of cases). This method of analysis is rapid, reproducible and extremely reliable in detecting presence of HER-2/neu gene amplification and should have clinical utility.

  6. Humanization of the anti-CD18 antibody 6.7: an unexpected effect of a framework residue in binding to antigen.

    PubMed

    Caldas, Cristina; Coelho, Verônica; Kalil, Jorge; Moro, Ana Maria; Maranhão, Andrea Q; Brígido, Marcelo M

    2003-05-01

    Humanization of monoclonal antibodies by complementary determinant region (CDR)-grafting has become a standard procedure to improve the clinical usage of animal antibodies. However, antibody humanization may result in loss of activity that has been attributed to structural constraints in the framework structure. In this paper, we report the complete humanization of the 6.7 anti-human CD18 monoclonal antibody in a scFv form. We used a germline-based approach to design a humanized VL gene fragment and expressed it together with a previously described humanized VH. The designed humanized VL has only 14 mutations compared to the closest human germline sequence. The resulting humanized scFv maintained the binding capacity and specificity to human CD18 expressed on the cell surface of peripheral blood mononuclear cells (PBMC), and showed the same pattern of staining T-lymphocytes sub-populations, in comparison to the original monoclonal antibody. We observed an unexpected effect of a conserved mouse-human framework position (L37) that hinders the binding of the humanized scFv to antigen. This paper reveals a new framework residue that interferes with paratope and antigen binding and also reinforces the germline approach as a successful strategy to humanize antibodies.

  7. [Comparative Study for Anti-Hepatitis B Surface Antigen Titers Based on Two Measurement Methods: Using Monoclonal Antibodies Isolated from Hepatitis B Vaccinated Recipients].

    PubMed

    Oone, Kumiko; Kani, Satomi; Oohashi, Minoru; Shinkai, Noboru; Inoue, Takako; Wakimoto, Yukio; Tanaka, Yasuhito

    2015-08-01

    As anti-hepatitis B surface antigen (anti-HBs) titers vary depending on the measurement methods, we compared two different methods to measure anti-HBs titers in sera and HBs monoclonal antibodies. The sera from 182 HB virus-resolved patients who were negative for HBsAg but positive for antiHB core protein (HBc) and/or anti-HBs were obtained. The measurement of anti-HBs was compared using either Lumipulse G1200 or Architect i2000SR. Six different monoclonal antibody (mAbs) clones isolated from healthy individuals inoculated with hepatitis B vaccine Bimmugen (genotype C) were used. A statistically significant correlation in anti-HBs titers was found between the two methods tested (Y = 0.951X + 100.7, R = 0.813, p < 0.001), although anti-HBs titers in 72 samples (39.6%) measured by Architect were less than 50% of that by Lumipulse and 12 (6.6%) were opposite results. Measuring 2 mAbs with HBV neutralizing activity, the titers of the 116 antibody (1.0 μg/mL) were comparable (689.3 mIU/mL by Lumipulse and 440.7 mIU/mL by Architect), whereas those of the 478 antibody (1.0 μg/mL) were much lower by Architect than by Lumipulse (42.6 vs. 818.6 mIU/mL, respectively). Of four other mAbs without HBV neutralizing activity, equal titers were observed for one; two mAbs had less anti-HB titers by Architect; and one was below the cut-off index (< 5 mIU/mL). Anti-HBs titers measured by Architect are likely to be lower than by Lumipulse, and the potential ability to detect the 478 antibody with neutralizing activity is low, indicating that Architect might underestimate anti-HBs titers. Future studies should standardize the anti-HBs titer measurement system.

  8. Human Monoclonal Antibody 81.39a Effectively Neutralizes Emerging Influenza A Viruses of Group 1 and 2 Hemagglutinins

    PubMed Central

    Marjuki, Henju; Mishin, Vasiliy P.; Chai, Ning; Tan, Man-Wah; Newton, Elizabeth M.; Tegeris, John; Erlandson, Karl; Willis, Melissa; Jones, Joyce; Davis, Todd; Stevens, James

    2016-01-01

    ABSTRACT The pandemic threat posed by emerging zoonotic influenza A viruses necessitates development of antiviral agents effective against various antigenic subtypes. Human monoclonal antibody (hMAb) targeting the hemagglutinin (HA) stalk offers a promising approach to control influenza virus infections. Here, we investigated the ability of the hMAb 81.39a to inhibit in vitro replication of human and zoonotic viruses, representing 16 HA subtypes. The majority of viruses were effectively neutralized by 81.39a at a 50% effective concentration (EC50) of <0.01 to 4.9 μg/ml. Among group 2 HA viruses tested, a single A(H7N9) virus was not neutralized at 50 μg/ml; it contained HA2-Asp19Gly, an amino acid position previously associated with resistance to neutralization by the group 2 HA-neutralizing MAb CR8020. Notably, among group 1 HA viruses, H11-H13 and H16 subtypes were not neutralized at 50 μg/ml; they shared the substitution HA2-Asp19Asn/Ala. Conversely, H9 viruses harboring HA2-Asp19Ala were fully susceptible to neutralization. Therefore, amino acid variance at HA2-Asp19 has subtype-specific adverse effects on in vitro neutralization. Mice given a single injection (15 or 45 mg/kg of body weight) at 24 or 48 h after infection with recently emerged A(H5N2), A(H5N8), A(H6N1), or A(H7N9) viruses were protected from mortality and showed drastically reduced lung viral titers. Furthermore, 81.39a protected mice infected with A(H7N9) harboring HA2-Asp19Gly, although the antiviral effect was lessened. A(H1N1)pdm09-infected ferrets receiving a single dose (25 mg/kg) had reduced viral titers and showed less lung tissue injury, despite 24- to 72-h-delayed treatment. Taken together, this study provides experimental evidence for the therapeutic potential of 81.39a against diverse influenza A viruses. IMPORTANCE Zoonotic influenza viruses, such as A(H5N1) and A(H7N9) subtypes, have caused severe disease and deaths in humans, raising public health concerns. Development of novel

  9. Development of an Enzyme-Linked Immunosorbent Assay and Immunoaffinity Column Chromatography for Saikosaponin d Using an Anti-Saikosaponin d Monoclonal Antibody.

    PubMed

    Sai, Jiayang; Zhao, Yan; Shan, Wenchao; Qu, Baoping; Zhang, Yue; Cheng, Jinjun; Qu, Huihua; Wang, Qingguo

    2016-03-01

    This work developed a novel immunochemical approach for the quality control of saikosaponin d using an enzyme-linked immunosorbent assay. Splenocytes from mice immunized with the saikosaponin d-bovine serum albumin conjugate were fused with the hypoxanthine-aminopterin-thymidine-sensitive mouse myeloma SP2/0 cell line, and a hybridoma secreting monoclonal antibody against saikosaponin d was successfully obtained. The prepared anti-saikosaponin d monoclonal antibody 1E7F3 has a novel characteristic, showing weak reactivity with compounds that are structurally related to saikosaponin d. Using monoclonal antibody 1E7F3, a specific and reliable enzyme-linked immunosorbent assay was developed to detect saikosaponin d. The system shows a full measurement range from 156.25 to 5000.00 ng × mL(-1). Both intra-assay and inter-assay repeatability and precision were achieved, with relative standard deviations lower than 10.00%. The recovery rates ranged from 92.36% to 101.00%, meeting the requirements for biological samples. There was a good correlation between the enzyme-linked immunosorbent assay and high-performance liquid chromatography analyses of saikosaponin d, and the saikosaponin d levels in formulated Chinese medicines were successfully determined. Furthermore, immunoaffinity column chromatography was established using this anti-saikosaponin d monoclonal antibody, and the elution profile of saikosaponin d was detected by a Bio-Rad QuadTec UV/Vis detector at 203 nm. The results demonstrate that we generated a reliable and more efficient assay system for measuring saikosaponin d and provide a potential approach for purifying and separating saikosaponin d. Georg Thieme Verlag KG Stuttgart · New York.

  10. Anti-inflammatory agents and monoHER protect against DOX-induced cardiotoxicity and accumulation of CML in mice

    PubMed Central

    Bruynzeel, A M E; Abou El Hassan, M A; Schalkwijk, C; Berkhof, J; Bast, A; Niessen, H W M; van der Vijgh, W J F

    2007-01-01

    Cardiac damage is the major limiting factor for the clinical use of doxorubicin (DOX). Preclinical studies indicate that inflammatory effects may be involved in DOX-induced cardiotoxicity. Nɛ-(carboxymethyl) lysine (CML) is suggested to be generated subsequent to oxidative stress, including inflammation. Therefore, the aim of this study was to investigate whether CML increased in the heart after DOX and whether anti-inflammatory agents reduced this effect in addition to their possible protection on DOX-induced cardiotoxicity. These effects were compared with those of the potential cardioprotector 7-monohydroxyethylrutoside (monoHER). BALB/c mice were treated with saline, DOX alone or DOX preceded by ketoprofen (KP), dexamethasone (DEX) or monoHER. Cardiac damage was evaluated according to Billingham. Nɛ-(carboxymethyl) lysine was quantified immunohistochemically. Compared to saline, a 21.6-fold increase of damaged cardiomyocytes was observed in mice treated with DOX (P<0.001). Addition of KP, DEX or monoHER before DOX significantly reduced the mean ratio of abnormal cardiomyocytes in comparison to mice treated with DOX alone (P⩽0.02). In addition, DOX induced a significant increase in the number of CML-stained intramyocardial vessels per mm2 (P=0.001) and also in the intensity of CML staining (P=0.001) compared with the saline-treated group. Nɛ-(carboxymethyl) lysine positivity was significantly reduced (P⩽0.01) by DOX-DEX, DOX-KP and DOX-monoHER. These results confirm that inflammation plays a role in DOX-induced cardiotoxicity, which is strengthened by the observed DOX-induced accumulation of CML, which can be reduced by anti-inflammatory agents and monoHER. PMID:17325706

  11. Targeting CXCR1/2 Significantly Reduces Breast Cancer Stem Cell Activity and Increases the Efficacy of Inhibiting HER2 via HER2-dependent and -independent Mechanisms

    PubMed Central

    Singh, Jagdeep K.; Farnie, Gillian; Bundred, Nigel J.; Simões, Bruno M; Shergill, Amrita; Landberg, Göran; Howell, Sacha; Clarke, Robert B.

    2012-01-01

    Purpose Breast cancer stem-like cells (CSCs) are an important therapeutic target as they are predicted to be responsible for tumour initiation, maintenance and metastases. Interleukin-8 (IL-8) is upregulated in breast cancer and associated with poor prognosis. Breast cancer cell line studies indicate that IL-8 via its cognate receptors, CXCR1 and CXCR2, is important in regulating breast CSC activity. We investigated the role of IL-8 in the regulation of CSC activity using patient-derived breast cancers and determined the potential benefit of combining CXCR1/2 inhibition with HER2-targeted therapy. Experimental design CSC activity of metastatic and invasive human breast cancers (n=19) was assessed ex vivo using the mammosphere colony forming assay. Results Metastatic fluid IL-8 level correlated directly with mammosphere formation (r=0.652; P<0.05; n=10). Recombinant IL-8 directly increased mammosphere formation/self-renewal in metastatic and invasive breast cancers (n=17). IL-8 induced activation of EGFR/HER2 and downstream signalling pathways and effects were abrogated by inhibition of SRC, EGFR/HER2, PI3K or MEK. Furthermore, lapatinib inhibited the mammosphere-promoting effect of IL-8 in both HER2-positive and negative patient-derived cancers. CXCR1/2 inhibition also blocked the effect of IL-8 on mammosphere formation and added to the efficacy of lapatinib in HER2-positive cancers. Conclusions These studies establish a role for IL-8 in the regulation of patient-derived breast CSC activity and demonstrate that IL-8/CXCR1/2 signalling is partly mediated via a novel SRC and EGFR/HER2-dependent pathway. Combining CXCR1/2 inhibitors with current HER2-targeted therapies has potential as an effective therapeutic strategy to reduce CSC activity in breast cancer and improve the survival of HER2-positive patients. PMID:23149820

  12. Mapping of cat albumin using monoclonal antibodies: identification of determinants common to cat and dog.

    PubMed Central

    Boutin, Y; Hébert, J; Vrancken, E R; Mourad, W

    1989-01-01

    Cat and dog albumins from commercial extracts were used to produce monoclonal antibodies (MoAb). Anti-cat albumin MoAb recognized both cat and dog albumin equally, as did anti-dog albumin MoAb; this confirms cross-reactivity between cat and dog. The MoAb were separated into two groups according to their epitopic specificity; they recognized two overlapping epitopes of cat albumin. Furthermore, by competitive inhibition of radio-allergosorbent test (RAST), it was shown that one MoAb group inhibited significantly the binding of human IgE antibodies (from a pool of 13 patients allergic to both cats and dogs) to insolubilized cat or dog extracts. These observations suggest that murine anti-cat or anti-dog MoAb and human IgE antibodies recognize identical or closely related determinants on cat and dog albumin. Images Fig. 1 Fig. 2 PMID:2478325

  13. Optimized molecular design of ADAPT-based HER2-imaging probes labelled with 111In and 68Ga.

    PubMed

    Lindbo, Sarah; Garousi, Javad; Mitran, Bogdan; Vorobyeva, Anzhelika; Oroujeni, Maryam; Orlova, Anna; Hober, Sophia; Tolmachev, Vladimir

    2018-06-04

    Radionuclide molecular imaging is a promising tool for visualization of cancer associated molecular abnormalities in vivo and stratification of patients for specific therapies. ADAPT is a new type of small engineered proteins based on the scaffold of an albumin binding domain of protein G. ADAPTs have been utilized to select and develop high affinity binders to different proteinaceous targets. ADAPT6 binds to human epidermal growth factor 2 (HER2) with low nanomolar affinity and can be used for its in vivo visualization. Molecular design of 111 In-labeled anti-HER2 ADAPT has been optimized in several earlier studies. In this study, we made a direct comparison of two of the most promising variants, having either a DEAVDANS or a (HE) 3 DANS sequence at the N-terminus, conjugated with a maleimido derivative of DOTA to a GSSC amino acids sequence at the C-terminus. The variants (designated DOTA-C 59 - DEAVDANS-ADAPT6-GSSC and DOTA-C 61 -(HE) 3 DANS-ADAPT6-GSSC) were stably labeled with 111 In for SPECT and 68 Ga for PET. Biodistribution of labeled ADAPT variants was evaluated in nude mice bearing human tumor xenografts with different levels of HER2 expression. Both variants enabled clear discrimination between tumors with high and low levels of HER2 expression. 111 In-labeled ADAPT6 derivatives provided higher tumor-to-organ ratios compared to 68 Ga-labeled counterparts. The best performing variant was DOTA-C 61 -(HE) 3 DANS-ADAPT6-GSSC, providing tumor-to-blood ratios of 208±36 and 109±17 at 3 h for 111 In and 68 Ga labels, respectively.

  14. Epitope mapping of the gastrin-releasing peptide/anti-bombesin monoclonal antibody complex by proteolysis followed by matrix-assisted laser desorption ionization mass spectrometry.

    PubMed

    Papac, D I; Hoyes, J; Tomer, K B

    1994-09-01

    We have developed a method to rapidly identify the antigenic determinant for an antibody using in situ proteolysis of an immobilized antigen-antibody complex followed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI/TOF). A mouse anti-bombesin monoclonal antibody was immobilized to agarose beads and then the antigen, gastrin-releasing peptide (GRP), was allowed to bind. Direct analysis of the immobilized antigen-antibody complex by MALDI/TOF is demonstrated and allows identification of ca. 1 pmol of the bound GRP. To identify the epitope, the immobilized antigen-antibody complex was subjected to proteolysis with trypsin, chymotrypsin, thermolysin, and aminopeptidase M. Following proteolysis, the part of the antigen in contact with the antibody and protected from proteolysis was identified directly by MALDI/TOF. Subsequently, the epitope was eluted from the immobilized antibody with 0.1 M glycine buffer (pH 2.3), separated by reversed-phase HPLC, and its identity confirmed by MALDI/TOF. Using this approach, the epitope for the anti-bombesin monoclonal antibody was shown to comprise the last 7-8 residues (HWAVGHLM-NH2) of GRP.

  15. Local convection-enhanced delivery of an anti-CD40 agonistic monoclonal antibody induces antitumor effects in mouse glioma models

    PubMed Central

    Shoji, Takuhiro; Saito, Ryuta; Chonan, Masashi; Shibahara, Ichiyo; Sato, Aya; Kanamori, Masayuki; Sonoda, Yukihiko; Kondo, Toru; Ishii, Naoto; Tominaga, Teiji

    2016-01-01

    Background Glioblastoma is one of the most malignant brain tumors in adults and has a dismal prognosis. In a previous report, we reported that CD40, a TNF-R-related cell surface receptor, and its ligand CD40L were associated with glioma outcomes. Here we attempted to activate CD40 signaling in the tumor and determine if it exerted therapeutic efficacy. Methods CD40 expression was examined in 3 mouse glioma cell lines (GL261, NSCL61, and bRiTs-G3) and 5 human glioma cell lines (U87, U251, U373, T98, and A172). NSCL61 and bRiTs-G3, as glioma stem cells, also expressed the glioma stem cell markers MELK and CD44. In vitro, we demonstrated direct antitumor effects of an anti-CD40 agonistic monoclonal antibody (FGK45) against the cell lines. The efficacy of FGK45 was examined by local convection-enhanced delivery of the monoclonal antibody against each glioma model. Results CD40 was expressed in all mouse and human cell lines tested and was found at the cell membrane of each of the 3 mouse cell lines. FGK45 administration induced significant, direct antitumor effects in vitro. The local delivery of FGK45 significantly prolonged survival compared with controls in the NSCL61 and bRiTs-G3 models, but the effect was not significant in the GL261 model. Increases in apoptosis and CD4+ and CD8+ T cell infiltration were observed in the bRiTs-G3 model after FGK45 treatment. Conclusions Local delivery of FGK45 significantly prolonged survival in glioma stem cell models. Thus, local delivery of this monoclonal antibody is promising for immunotherapy against gliomas. PMID:26917236

  16. Development of an enzyme-linked immunosorbent assay and immunoaffinity chromatography for glycyrrhizic acid using an anti-glycyrrhizic acid monoclonal antibody.

    PubMed

    Zhang, Yue; Qu, Huihua; Zeng, Wenhao; Zhao, Yan; Shan, Wenchao; Wang, Xueqian; Wang, Qingguo; Zhao, Yan

    2015-07-01

    In this work, a new monoclonal antibody specific for glycyrrhizic acid was prepared and characterized. A hybridoma secreting an anti-glycyrrhizic acid monoclonal antibody was produced by fusing splenocytes from a mouse immunized against a glycyrrhizic acid-bovine serum albumin conjugate with the hypoxanthine-aminopterin-thymidine-sensitive mouse myeloma cell line (Sp2/0-Ag14). Subsequently, an indirect, competitive enzyme-linked immunosorbent assay for glycyrrhizic acid was developed using the monoclonal antibody. In this assay, we detected an effective measuring range of 78.12-2500 ng/mL. Both intra-assay and inter-assay repeatability and precision were achieved, with relative standard deviations lower than 10%. In addition, glycyrrhizic acid levels in both formulated Chinese medicines and biological samples were determined with high sensitivity and efficiency. We then successfully developed a reliable immunoaffinity chromatography to separate glycyrrhizic acid completely from its parent medicine. These methods will contribute to further research investigations to better understand the interactions of glycyrrhizic acid with other drugs in the complex system of traditional Chinese medicine. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. An Anti-C1s Monoclonal, TNT003, Inhibits Complement Activation Induced by Antibodies Against HLA.

    PubMed

    Thomas, K A; Valenzuela, N M; Gjertson, D; Mulder, A; Fishbein, M C; Parry, G C; Panicker, S; Reed, E F

    2015-08-01

    Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro. © 2015 The Authors. American Journal of Transplantation Published by Wiley Periodicals, Inc.

  18. An Anti-C1s Monoclonal, TNT003, Inhibits Complement Activation Induced by Antibodies Against HLA

    PubMed Central

    Thomas, K A; Valenzuela, N M; Gjertson, D; Mulder, A; Fishbein, M C; Parry, G C; Panicker, S; Reed, E F

    2015-01-01

    Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab′)2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro. PMID:25904443

  19. Detection of DNA damage in individual cells by flow cytometric analysis using anti-DNA monoclonal antibody

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Frankfurt, O.S.

    A new method for the measurement of DNA damage in individual cells treated with alkylating agents is described. The method is based on the binding of anti-DNA monoclonal antibody to DNA in situ. Binding of antibody was evaluated by flow cytometry with indirect immunofluorescence. No binding of antibody to DNA in non-treated HeLa S3 cells was detected. Treatment of cells with HN2 or L-phenylalanine mustard induced binding of antibody to DNA in situ. Binding of antibody was observed after treating cells with doses of drugs which reduced the surviving fraction below 20%. Intensity of binding increased in proportion to themore » drug dose. In HN2-treated cells a cell subset with the lowest antibody binding was observed among cells in G1 phase. Binding of antibody to DNA in HN2-treated cells was eliminated by single-strand (ss) specific S1 nuclease. In competition assay, antibody was inhibited by thermally denatured DNA, but not by native double-stranded (ds) DNA, RNA, nucleosides and deoxyribohomopolymers. Immunoreactivity of cells with the monoclonal antibody F7-26 may be a useful probe for the assessment of cell damage induced by alkylating agents, especially in heterogeneous cell populations.« less

  20. CRISPR-mediated targeting of HER2 inhibits cell proliferation through a dominant negative mutation.

    PubMed

    Wang, Huajing; Sun, William

    2017-01-28

    With the discovery of the CRISPR/Cas9 technology, genome editing could be performed in a rapid, precise and effective manner. Its potential applications in functional interrogation of cancer-causing genes and cancer therapy have been extensively explored. In this study, we demonstrated the use of the CRISPR/Cas9 system to directly target the oncogene HER2. Directing Cas9 to exons of the HER2 gene inhibited cell growth in breast cancer cell lines that harbor amplification of the HER2 locus. The inhibitory effect was potentiated with the addition of PARP inhibitors. Unexpectedly, CRISPR-induced mutations did not significantly affect the level of HER2 protein expression. Instead, CRISPR targeting appeared to exert its effect through a dominant negative mutation. This HER2 mutant interfered with the MAPK/ERK axis of HER2 downstream signaling. Our work provides a novel mechanism underlying the anti-cancer effects of HER2-targeting by CRISPR/Cas9, which is distinct from the clinical drug Herceptin. In addition, it opens up the possibility that incomplete CRISPR targeting of certain oncogenes could still have therapeutic value by generation of dominant negative mutants. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. A new bead-based human platelet antigen antibodies detection assay versus the monoclonal antibody immobilization of platelet antigens assay.

    PubMed

    Porcelijn, Leendert; Huiskes, Elly; Comijs-van Osselen, Ilona; Chhatta, Aniska; Rathore, Vipul; Meyers, Matthew; de Haas, Masja

    2014-06-01

    The performance of a newly developed Luminex bead-based platelet (PLT) antibody detection method (PAKLx) was compared with the monoclonal antibody immobilization of PLT antigens (MAIPA) assay and the LifeScreen Deluxe Luminex bead-based HLA Class I antibody detection method (LMX). Six sera containing anti-human PLT antigen (HPA)-1a (n=2), HPA-1b, HPA-2b, HPA-3a, or HPA-5b were tested in titration. A total of 194 sera, including HPA-1a, -1b, -2a, -2b, -3a, -5a, and -5b antibodies with or without HLA antibodies (n=63); glycoprotein (GP) IV antibodies (n=1); PLT autoantibodies (n=3); HLA antibodies (n=45); and samples with no PLT-reactive antibodies (n=82), were tested in both assays. Comparable levels of sensitivity were obtained for the MAIPA and PAKLx. The PAKLx showed four (6%) false-negative results in 67 sera with HPA or GP-reactive antibodies: anti-HPA-3a (n=1) or anti-HPA-5b (n=3). The PAKLx showed in 10 of the total 194 samples (5%) the presence of antibodies not detected by the MAIPA. This concerned broadly GP-reactive antibodies (n=7), anti-GPIIb/IIIa combined with anti-HPA-3a (n=1), anti-HPA-1a (borderline, n=1), and anti-GPIV (n=1). Testing 175 sera for anti-HLA Class I antibodies in the PAKLx and LMX showed four discrepant results: PAKLx negative and LMX positive, n=3 and n=1, respectively. For the vast majority of the specimens tested (93%) the results of the PAKLx were in concordance with the MAIPA. The PAKLx is a fast, easy to perform, and sensitive PLT antibody screening method. © 2013 AABB.

  2. Anti-human neutrophil antigen-1a, -1b, and -2 antibodies in neonates and children with immune neutropenias analyzed by extracted granulocyte antigen immunofluorescence assay.

    PubMed

    Onodera, Rie; Kurita, Emi; Taniguchi, Kikuyo; Karakawa, Shuhei; Okada, Satoshi; Kihara, Hirotaka; Fujii, Teruhisa; Kobayashi, Masao

    2017-11-01

    Anti-human neutrophil antigen (HNA) antibodies have been implicated in the development of neonatal alloimmune neutropenia (NAN) and autoimmune neutropenia (AIN). There are many conventional assay methods that detect anti-HNA antibodies. However, a method to measure multiple samples and detect several anti-HNA antibodies simultaneously is needed. We developed a new method, the extracted granulocyte antigen immunofluorescence assay (EGIFA), to analyze anti-HNA-1a, -1b, and -2 antibodies in sera. The results obtained by EGIFA were evaluated in comparison with those from several standard assay methods. Anti-HNA antibodies in serum samples from nine familial cases with suspected NAN (n = 19) and children with suspected AIN (n = 88) were also measured by EGIFA. The evaluation of nine serum samples with anti-HNA antibodies suggested that EGIFA demonstrated equivalent specificity and superior sensitivity to monoclonal antibody-specific immobilization of granulocyte antigens and had comparable sensitivity to the granulocyte indirect immunofluorescence test. EGIFA successfully detected anti-HNA-1a or -1b antibodies in seven of nine familial cases with suspected NAN. EGIFA detected anti-HNA antibodies in 40.9% of children with suspected AIN. Among them, isolated anti-HNA-1a or -1b antibody was detected in 4.5 or 12.5% of children, respectively, and anti-HNA-2 antibody was identified in 3.4% of children. The 30.8% (16 of 52) of children negative for anti-HNA antibody by EGIFA were positive for anti-HLA antibody. EGIFA facilitated the measurement of anti-HNA-1a, -1b, and/or -2 antibodies in sera. The prompt measurement of anti-HNA antibodies will improve the diagnosis and clinical management of patients with suspected NAN or AIN. © 2017 AABB.

  3. HER-2 and HER-3 expression in liver metastases of patients with colorectal cancer.

    PubMed

    Styczen, Hanna; Nagelmeier, Iris; Beissbarth, Tim; Nietert, Manuel; Homayounfar, Kia; Sprenger, Thilo; Boczek, Ute; Stanek, Kathrin; Kitz, Julia; Wolff, Hendrik A; Ghadimi, B Michael; Middel, Peter; Liersch, Torsten; Rüschoff, Josef; Conradi, Lena-Christin

    2015-06-20

    In this study, we evaluate the frequency of HER-2 and HER-3 expression in liver metastases from patients with colorectal cancer (CRLM). We analyzed the potential of HER-2 and HER-3 as therapeutic targets and evaluated their prognostic value. Overall 208 patients with CRLM were enrolled. HER-2 and HER-3 expression were determined in metastatic tissue of diagnostic punch biopsies (n = 29) or resection specimens (n = 179). The results of immunohistochemistry (IHC) scoring and In-situ-hybridization (ISH)-amplification were correlated with clinical parameters and for the 179 resected patients with cancer-specific (CSS) and overall survival (OS). The mean follow-up time was 56.7 months. Positivity of HER-2 status (IHC score 2+/ISH+ and IHC 3+) was found in 8.2% of CRLM. High expression of HER-3 (IHC score 2+ and IHC 3+) was detected in 75.0% of liver metastases. CSS after liver surgery was determined and was independent from the HER-2 status (p = 0.963); however HER-3 was prognostic with a favorable course for patients showing an overexpression of HER-3 (p = 0.037). HER-2 overexpression occurs in only 8% of patients with CRLM but with 75% of cases HER-3 is frequently overexpressed in CRLM. Therefore, HER-2 and particularly HER-3 could serve as novel targets to be addressed within multimodal treatment approaches.

  4. A human monoclonal anti-TNF alpha antibody (adalimumab) reduces airway inflammation and ameliorates lung histology in a murine model of acute asthma.

    PubMed

    Catal, F; Mete, E; Tayman, C; Topal, E; Albayrak, A; Sert, H

    2015-01-01

    A few experimental studies related to asthma have unveiled the beneficial effects of TNF alpha blocking agents on the airway histology, cytokine levels in bronchoalveolar lavage and bronchial hyper-responsiveness. In the current study, we aimed to assess the effect of adalimumab on the inflammation and histology of asthma in a murine model. Twelve-week-old BALB/c (H-2d/d) female rats (n=18) were allocated into three groups, including (group I) control (phosphate-buffered saline was implemented), (group II) asthma induced with OVA (n=6), and (group III) asthma induced with OVA+treated with adalimumab (n=6). Rats were executed on the 28th day of the study. The lung samples were fixed in 10% neutral buffered formalin. Lung parenchyma, alveolus, peribronchial and perivascular inflammation were assessed. Lung pathological scoring was performed. Severity of lung damage was found to be reduced significantly in the asthma induced with OVA+treated with adalimumab group. When compared with the untreated group, adalimumab significantly reduced the inflammatory cells around the bronchi and bronchioles, and reduced inflammation of the alveolar wall and alveolar wall thickness as well (median score=1, p=0.52). Peribronchial smooth muscle hypertrophy and oedema were significantly reduced after adalimumab administration. Adalimumab (a human monoclonal anti-TNF alpha antibody) therapy significantly reduced the severity of lung damage by decreasing cellular infiltration and improvement on the lung histology in a murine model of acute asthma. Copyright © 2013 SEICAP. Published by Elsevier Espana. All rights reserved.

  5. Regular and low-dose aspirin, other non-steroidal anti-inflammatory medications and prospective risk of HER2-defined breast cancer: the California Teachers Study.

    PubMed

    Clarke, Christina A; Canchola, Alison J; Moy, Lisa M; Neuhausen, Susan L; Chung, Nadia T; Lacey, James V; Bernstein, Leslie

    2017-05-01

    Regular users of aspirin may have reduced risk of breast cancer. Few studies have addressed whether risk reduction pertains to specific breast cancer subtypes defined jointly by hormone receptor (estrogen and progesterone receptor) and human epidermal growth factor receptor 2 (HER2) expression. This study assessed the prospective risk of breast cancer (overall and by subtype) according to use of aspirin and other non-steroidal anti-inflammatory medications (NSAIDs) in a cohort of female public school professionals in California. In 1995 - 1996, participants in the California Teachers Study completed a baseline questionnaire on family history of cancer and other conditions, use of NSAIDs, menstrual and reproductive history, self-reported weight and height, living environment, diet, alcohol use, and physical activity. In 2005-2006, 57,164 participants provided some updated information, including use of NSAIDs and 1457 of these participants developed invasive breast cancer before January 2013. Multivariable Cox proportional hazards regression models provided hazard rate ratios (HRR) for the association between NSAID use and risk of invasive breast cancer as well as hormone receptor- and HER2-defined subtypes. Developing breast cancer was associated inversely with taking three or more tablets of low-dose aspirin per week (23% of participants). Among women reporting this exposure, the HRR was 0.84 (95% confidence interval (CI) 0.72-0.98) compared to those not taking NSAIDs and this was particularly evident in women with the hormone receptor-positive/HER2-negative subtype (HRR = 0.80, 95% CI 0.66-0.96). Use of three or more tablets of "other" NSAIDs was marginally associated with lower risk of breast cancer (HRR = 0.79, 95% CI 0.62-1.00). Other associations with NSAIDs were generally null. Our observation of reduced risk of breast cancer, among participants who took three or more tablets of low-dose aspirin weekly, is consistent with other reports looking at

  6. Dual targeting of HER3 and MEK may overcome HER3-dependent drug-resistance of colon cancers

    PubMed Central

    Bon, Giulia; Loria, Rossella; Amoreo, Carla Azzurra; Verdina, Alessandra; Sperduti, Isabella; Mastrofrancesco, Arianna; Soddu, Silvia; Diodoro, Maria Grazia; Mottolese, Marcella; Todaro, Matilde; Stassi, Giorgio; Milella, Michele; De Maria, Ruggero; Falcioni, Rita

    2017-01-01

    Although the medical treatment of colorectal cancer has evolved greatly in the last years, a significant portion of early-stage patients develops recurrence after therapies. The current clinical trials are directed to evaluate new drug combinations and treatment schedules. By the use of patient-derived or established colon cancer cell lines, we found that the tyrosine kinase receptor HER3 is involved in the mechanisms of resistance to therapies. In agreement, the immunohistochemical analysis of total and phospho-HER3 expression in 185 colorectal cancer specimens revealed a significant correlation with lower disease-free survival. Targeting HER3 by the use of the monoclonal antibody patritumab we found induction of growth arrest in all cell lines. Despite the high efficiency of patritumab in abrogating the HER3-dependent activation of PI3K pathway, the HER2 and EGFR-dependent MAPK pathway is activated as a compensatory mechanism. Interestingly, we found that the MEK-inhibitor trametinib inhibits, as expected, the MAPK pathway but induces the HER3-dependent activation of PI3K pathway. The combined treatment results in the abrogation of both PI3K and MAPK pathways and in a significant reduction of cell proliferation and survival. These data suggest a new strategy of therapy for HER3-overexpressing colon cancers. PMID:29312543

  7. Effect of kinase inhibitors on the therapeutic properties of monoclonal antibodies

    PubMed Central

    Duong, Minh Ngoc; Matera, Eva-Laure; Mathé, Doriane; Evesque, Anne; Valsesia-Wittmann, Sandrine; Clémenceau, Béatrice; Dumontet, Charles

    2015-01-01

    Targeted therapies of malignancies currently consist of therapeutic monoclonal antibodies and small molecule kinase inhibitors. The combination of these novel agents raises the issue of potential antagonisms. We evaluated the potential effect of 4 kinase inhibitors, including the Bruton tyrosine kinase inhibitor ibrutinib, and 3 PI3K inhibitors idelalisib, NVP-BEZ235 and LY294002, on the effects of the 3 monoclonal antibodies, rituximab and obinutuzumab (directed against CD20) and trastuzumab (directed against HER2). We found that ibrutinib potently inhibits antibody-dependent cell-mediated cytotoxicity exerted by all antibodies, with a 50% inhibitory concentration of 0.2 microM for trastuzumab, 0.5 microM for rituximab and 2 microM for obinutuzumab, suggesting a lesser effect in combination with obinutuzumab than with rituximab. The 4 kinase inhibitors were found to inhibit phagocytosis by fresh human neutrophils, as well as antibody-dependent cellular phagocytosis induced by the 3 antibodies. Conversely co-administration of ibrutinib with rituximab, obinutuzumab or trastuzumab did not demonstrate any inhibitory effect of ibrutinib in vivo in murine xenograft models. In conclusion, some kinase inhibitors, in particular, ibrutinib, are likely to exert inhibitory effects on innate immune cells. However, these effects do not compromise the antitumor activity of monoclonal antibodies in vivo in the models that were evaluated. PMID:25523586

  8. Development and characterization of a TAPIR-like mouse monoclonal antibody to amyloid-beta.

    PubMed

    Wang, Jun; Hara, Hideo; Makifuchi, Takao; Tabira, Takeshi

    2008-06-01

    Tissue amyloid plaque immuno-reactive (TAPIR) antibody was better related to the effect of immunotherapy in Alzheimer's disease (AD) than ELISA antibody. Here we used a hybridoma technique to develop a TAPIR-like anti-human amyloid-beta (Abeta) mouse monoclonal antibody. The obtained monoclonal antibody, 3.4A10, was an IgG2b isotype and recognized N-terminal portion of Abeta1-42 without binding denatured or native amyloid-beta protein precursor. It had higher affinity to Abeta1-42 than to Abeta1-40 by Biacore affinity analysis and stained preferably the peripheral part of senile plaques and recognized the plaque core less than 4G8. It inhibited the Abeta1-42 fibril formation as well as degraded pre-aggregated Abeta1-42 peptide in a thioflavin T fluorescence spectrophotometry assay. The in vivo studies showed that 3.4A10 treatment decreased amyloid burden compared to the control group and significantly reduced Abeta42 levels rather than Abeta40 levels in brain lysates as well as the Abeta*56 oligomer (12mer) in TBS fraction of the brain lysates. 3.4A10 entered brain and decorated some plaques, which is surrounded by more Iba1-positive microglia. 3.4A10 therapy did not induce lymphocytic infiltration and obvious increase in microhemorrhage. We conclude that 3.4A10 is a TAPIR-like anti-human amyloid monoclonal antibody, and has a potential of therapeutic application for AD.

  9. Determination of HER2 amplification status in breast cancer cells using Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Bi, Xiaohong; Rexer, Brent; Arteaga, Carlos L.; Guo, Mingsheng; Li, Ming; Mahadevan-Jansen, Anita

    2010-02-01

    The overexpression of HER2 (human epidermal growth factor receptor 2) in breast cancer is associated with increased disease recurrence and worse prognosis. Current diagnosis of HER2 positive breast cancer is time consuming with an estimated 20% inaccuracy. Raman spectroscopy is a proven method for pathological diagnosis based on the molecular composition of tissues. This study aimed to determine the feasibility of Raman spectroscopy to differentially identify the amplification of HER2 in cells. Three cell lines including BT474 (HER2 overexpressing breast cancer cell), MCF-10A (human breast epithelial cell), and MCF-10A with overexpressing HER2, were investigated using a bench top confocal Raman system. A diagnostic algorithm based on generalized linear model (GLM) with elastic-net penalties was established to discriminate 318 spectra collected from the cells, and to identify the spectra regions that differentiate the cell lines. The algorithm was able to differentially identify BT474 breast cancer cells with an overall sensitivity of 100% and specificity of 99%. The results demonstrate the capability of Raman spectroscopy to determine HER2 status in cells. Raman spectroscopy shows promise for application in the diagnosis of HER2 positive breast cancer in clinical practice.

  10. CTL-Tumor Cell Interaction: The Generation of Molecular Probes of Monitoring the HLA-A*0201-HER-2/neu Peptide Complex

    DTIC Science & Technology

    2005-03-01

    anti- HLA -A2, -A24, -A28 mAb CR11-351 (13,14); anti- HLA -A2, -A28 mAb KS-1 (14); anti- HLA -B7, - B27 , -Bw42, -Bw54, -Bw55, -Bw56, -Bw67, -Bw73 mAb KS-4 (15...AD Award Number: W81XWH-04-1-0372 TITLE: CTL-Tumor Cell Interaction: The Generation of Molecular Probes of Monitoring the HLA -A*0201-HER-2/neu...AND SUBTITLE 5. FUNDING NUMBERS CTL-Tumor Cell Interaction: The Generation of Molecular W81XWH-04-1-0372 Probes of Monitoring the HLA -A*0201-HER-2/neu

  11. Idiotypic Cascades in Cancer Patients Treated with Monoclonal Antibody CO17-1A

    NASA Astrophysics Data System (ADS)

    Wettendorff, Martine; Iliopoulos, Dimitrios; Tempero, Margaret; Kay, David; Defreitas, Elaine; Koprowski, Hilary; Herlyn, Dorothee

    1989-05-01

    We have previously shown that gastrointestinal cancer patients treated with monoclonal antibody CO17-1A (Ab1) developed anti-idiotypic antibodies (Ab2) to the Ab1. We now demonstrate that patients produce anti-anti-idiotypic antibodies (Ab3) to their autologous Ab2. Ab3 were demonstrated in culture supernatants of peripheral blood mononuclear cells from five Ab1-treated patients after stimulation of the cells with heterologous Ab2 that functionally mimicked the tumor antigen (Ag) defined by Ab1 and immunologically cross reacted with the patients' Ab2. Ab3 shared idiotopes with Ab1 and were Ab1-like in their binding specificities to tumor cells, Ag, and Ab2. Such antibodies were also elicited by stimulating cells with Ag. However, they were not produced by stimulating posttreatment mononuclear cells with control proteins or by stimulating pretreatment cells with either Ag or Ab2. Our results demonstrate idiotypic cascades in cancer patients treated with monoclonal antibody. Ag-specific Ab3 responses may underlie delayed clinical responses often observed in cancer patients treated with monoclonal antibodies of various specificities.

  12. Characterisation of an engineered trastuzumab IgE antibody and effector cell mechanisms targeting HER2/neu-positive tumour cells

    PubMed Central

    2010-01-01

    Trastuzumab (Herceptin®), a humanized IgG1 antibody raised against the human epidermal growth factor receptor 2 (HER2/neu), is the main antibody in clinical use against breast cancer. Pre-clinical evidence and clinical studies indicate that trastuzumab employs several anti-tumour mechanisms that most likely contribute to enhanced survival of patients with HER2/neu-positive breast carcinomas. New strategies are aimed at improving antibody-based therapeutics like trastuzumab, e.g. by enhancing antibody-mediated effector function mechanisms. Based on our previous findings that a chimaeric ovarian tumour antigen-specific IgE antibody showed greater efficacy in tumour cell killing, compared to the corresponding IgG1 antibody, we have produced an IgE homologue of trastuzumab. Trastuzumab IgE was engineered with the same light- and heavy-chain variable-regions as trastuzumab, but with an epsilon in place of the gamma-1 heavy-chain constant region. We describe the physical characterisation and ligand binding properties of the trastuzumab IgE and elucidate its potential anti-tumour activities in functional assays. Both trastuzumab and trastuzumab IgE can activate monocytic cells to kill tumour cells, but they operate by different mechanisms: trastuzumab functions in antibody-dependent cell-mediated phagocytosis (ADCP), whereas trastuzumab IgE functions in antibody-dependent cell-mediated cytotoxicity (ADCC). Trastuzumab IgE, incubated with mast cells and HER2/neu-expressing tumour cells, triggers mast cell degranulation, recruiting against cancer cells a potent immune response, characteristic of allergic reactions. Finally, in viability assays both antibodies mediate comparable levels of tumour cell growth arrest. These functional characteristics of trastuzumab IgE, some distinct from those of trastuzumab, indicate its potential to complement or improve upon the existing clinical benefits of trastuzumab. PMID:18941743

  13. Blockade of epidermal growth factor- or heregulin-dependent ErbB2 activation with the anti-ErbB2 monoclonal antibody 2C4 has divergent downstream signaling and growth effects.

    PubMed

    Jackson, James G; St Clair, Patricia; Sliwkowski, Mark X; Brattain, Michael G

    2004-04-01

    Due to heterodimerization and a variety of stimulating ligands, the ErbB receptor system is both diverse and flexible, which proves particularly advantageous to the aberrant signaling of cancer cells. However, specific mechanisms of how a particular receptor contributes to generating the flexibility that leads to aberrant growth regulation have not been well described. We compared the utilization of ErbB2 in response to epidermal growth factor (EGF) and heregulin stimulation in colon carcinoma cells. Anti-ErbB2 monoclonal antibody 2C4 blocked heregulin-stimulated phosphorylation of ErbB2 and ErbB3; activation of mitogen-activated protein kinase (MAPK), phosphatidylinositol 3'-kinase (PI3K), and Akt; proliferation; and anchorage-independent growth. 2C4 blocked EGF-mediated phosphorylation of ErbB2 and inhibited PI3K/Akt and anchorage-independent growth but did not affect ErbB1 or MAPK. Immunoprecipitations showed that ErbB3 and Grb2-associated binder (Gab) 1 were phosphorylated and associated with PI3K activity after heregulin treatment and that Gab1 and Gab2, but not ErbB3, were phosphorylated and associated with PI3K activity after EGF treatment. These data show that monoclonal antibody 2C4 inhibited all aspects of heregulin signaling as well as anchorage-independent and monolayer growth. Furthermore, we identify ErbB2 as a critical component of EGF signaling to the Gab1/Gab2-PI3K-Akt pathway and anchorage-independent growth, but EGF stimulation of MAPK and monolayer growth can occur efficiently without the contribution of ErbB2.

  14. Acute inflammatory neuropathy with monoclonal anti-GM2 IgM antibodies, IgM-κ paraprotein and additional autoimmune processes in association with a diffuse large B-cell non-Hodgkin's lymphoma.

    PubMed

    Milnik, Annette; Roggenbuck, Dirk; Conrad, Karsten; Bartels, Claudius

    2013-01-21

    Lymphoproliferative disorders are often associated with autoimmune processes preceding or following the occurrence of a lymphoma. Here, we describe a patient with a history of recurrent diffuse large B-cell non-Hodgkin's lymphoma who suffered from an acute inflammatory neuropathy with specific monoclonal anti-GM2 IgM antibodies and associated IgM-κ paraprotein. It was possible in this case to prove that both, anti-GM2 IgM antibodies and IgM-κ paraprotein, share the same binding characteristic. In addition, the patient possibly suffered from an immune thrombocytopenia and an early-stage bullous pemphigoid with anti-BP-230 IgG antibodies. Intravenous immunoglobulin and plasmapheresis alleviated the acute neuropathy and thrombocytopenia, while the bullous pemphigoid has been aggravated. In summary, the simultaneous occurrence of multiple autoimmune processes was a sign of a dysfunctional immune system preceding the relapse of a B-cell non-Hodgkin's lymphoma.

  15. Early short-term treatment with neutralizing human monoclonal antibodies halts SHIV infection in newborn macaques

    PubMed Central

    Hessell, Ann J.; Jaworski, J. Pablo; Epson, Erin; Matsuda, Kenta; Pandey, Shilpi; Kahl, Christoph; Reed, Jason; Sutton, William F.; Hammond, Katherine B.; Cheever, Tracy A.; Barnette, Philip T.; Legasse, Alfred W.; Planer, Shannon; Stanton, Jeffrey J.; Pegu, Amarendra; Chen, Xuejun; Wang, Keyun; Siess, Don; Burke, David; Park, Byung S.; Axthelm, Michael K.; Lewis, Anne; Hirsch, Vanessa M.; Graham, Barney S.; Mascola, John R.; Sacha, Jonah B.; Haigwood, Nancy L.

    2016-01-01

    Prevention of mother to child transmission (MTCT) of HIV remains a major objective where antenatal care is not readily accessible. We tested anti-HIV-1 human neutralizing monoclonal antibodies (NmAb) as post-exposure therapy in an infant macaque model for intrapartum MTCT. One-month-old rhesus macaques were inoculated orally with SHIVSF162P3. On days 1, 4, 7, and 10 after virus exposure, we injected animals subcutaneously with NmAbs and quantified systemic distribution of NmAbs in multiple tissues within 24 h following administration. Replicating virus was found in multiple tissues by day 1 in animals without treatment. All NmAb-treated macaques were free of virus in blood and tissues at 6 months post-exposure. We detected no anti-SHIV T cell responses in blood or tissues at necropsy, and no virus emerged following CD8+ T cell depletion. These results suggest early passive immunotherapy can eliminate early viral foci and thereby prevent the establishment of viral reservoirs. PMID:26998834

  16. Notch-1-PTEN-ERK1/2 signaling axis promotes HER2+ breast cancer cell proliferation and stem cell survival.

    PubMed

    Baker, Andrew; Wyatt, Debra; Bocchetta, Maurizio; Li, Jun; Filipovic, Aleksandra; Green, Andrew; Peiffer, Daniel S; Fuqua, Suzanne; Miele, Lucio; Albain, Kathy S; Osipo, Clodia

    2018-05-10

    Trastuzumab targets the HER2 receptor on breast cancer cells to attenuate HER2-driven tumor growth. However, resistance to trastuzumab-based therapy remains a major clinical problem for women with HER2+ breast cancer. Breast cancer stem cells (BCSCs) are suggested to be responsible for drug resistance and tumor recurrence. Notch signaling has been shown to promote BCSC survival and self-renewal. Trastuzumab-resistant cells have increased Notch-1 expression. Notch signaling drives cell proliferation in vitro and is required for tumor recurrence in vivo. We demonstrate herein a mechanism by which Notch-1 is required for trastuzumab resistance by repressing PTEN expression to contribute to activation of ERK1/2 signaling. Furthermore, Notch-1-mediated inhibition of PTEN is necessary for BCSC survival in vitro and in vivo. Inhibition of MEK1/2-ERK1/2 signaling in trastuzumab-resistant breast cancer cells mimics effects of Notch-1 knockdown on bulk cell proliferation and BCSC survival. These findings suggest that Notch-1 contributes to trastuzumab resistance by repressing PTEN and this may lead to hyperactivation of ERK1/2 signaling. Furthermore, high Notch-1 and low PTEN mRNA expression may predict poorer overall survival in women with breast cancer. Notch-1 protein expression predicts poorer survival in women with HER2+ breast cancer. These results support a potential future clinical trial combining anti-Notch-1 and anti-MEK/ERK therapy for trastuzumab-resistant breast cancer.

  17. Characterization of chimpanzee/human monoclonal antibodies to vaccinia virus A33 glycoprotein and its variola virus homolog in vitro and in a vaccinia virus mouse protection model.

    PubMed

    Chen, Zhaochun; Earl, Patricia; Americo, Jeffrey; Damon, Inger; Smith, Scott K; Yu, Fujuan; Sebrell, Andrew; Emerson, Suzanne; Cohen, Gary; Eisenberg, Roselyn J; Gorshkova, Inna; Schuck, Peter; Satterfield, William; Moss, Bernard; Purcell, Robert

    2007-09-01

    Three distinct chimpanzee Fabs against the A33 envelope glycoprotein of vaccinia virus were isolated and converted into complete monoclonal antibodies (MAbs) with human gamma 1 heavy-chain constant regions. The three MAbs (6C, 12C, and 12F) displayed high binding affinities to A33 (K(d) of 0.14 nM to 20 nM) and may recognize the same epitope, which was determined to be conformational and located within amino acid residues 99 to 185 at the C terminus of A33. One or more of the MAbs were shown to reduce the spread of vaccinia virus as well as variola virus (the causative agent of smallpox) in vitro and to more effectively protect mice when administered before or 2 days after intranasal challenge with virulent vaccinia virus than a previously isolated mouse anti-A33 MAb (1G10) or vaccinia virus immunoglobulin. The protective efficacy afforded by anti-A33 MAb was comparable to that of a previously isolated chimpanzee/human anti-B5 MAb. The combination of anti-A33 MAb and anti-B5 MAb did not synergize the protective efficacy. These chimpanzee/human anti-A33 MAbs may be useful in the prevention and treatment of vaccinia virus-induced complications of vaccination against smallpox and may also be effective in the immunoprophylaxis and immunotherapy of smallpox and other orthopoxvirus diseases.

  18. DS-8201a, A Novel HER2-Targeting ADC with a Novel DNA Topoisomerase I Inhibitor, Demonstrates a Promising Antitumor Efficacy with Differentiation from T-DM1.

    PubMed

    Ogitani, Yusuke; Aida, Tetsuo; Hagihara, Katsunobu; Yamaguchi, Junko; Ishii, Chiaki; Harada, Naoya; Soma, Masako; Okamoto, Hiromi; Oitate, Masataka; Arakawa, Shingo; Hirai, Takehiro; Atsumi, Ryo; Nakada, Takashi; Hayakawa, Ichiro; Abe, Yuki; Agatsuma, Toshinori

    2016-10-15

    An anti-HER2 antibody-drug conjugate with a novel topoisomerase I inhibitor, DS-8201a, was generated as a new antitumor drug candidate, and its preclinical pharmacologic profile was assessed. In vitro and in vivo pharmacologic activities of DS-8201a were evaluated and compared with T-DM1 in several HER2-positive cell lines and patient-derived xenograft (PDX) models. The mechanism of action for the efficacy was also evaluated. Pharmacokinetics in cynomolgus monkeys and the safety profiles in rats and cynomolgus monkeys were assessed. DS-8201a exhibited a HER2 expression-dependent cell growth-inhibitory activity and induced tumor regression with a single dosing at more than 1 mg/kg in a HER2-positive gastric cancer NCI-N87 model. Binding activity to HER2 and ADCC activity of DS-8201a were comparable with unconjugated anti-HER2 antibody. DS-8201a also showed an inhibitory activity to Akt phosphorylation. DS-8201a induced phosphorylation of Chk1 and Histone H2A.X, the markers of DNA damage. Pharmacokinetics and safety profiles of DS-8201a were favorable and the highest non-severely toxic dose was 30 mg/kg in cynomolgus monkeys, supporting DS-8201a as being well tolerated in humans. DS-8201a was effective in a T-DM1-insensitive PDX model with high HER2 expression. DS-8201a, but not T-DM1, demonstrated antitumor efficacy against several breast cancer PDX models with low HER2 expression. DS-8201a exhibited a potent antitumor activity in a broad selection of HER2-positive models and favorable pharmacokinetics and safety profiles. The results demonstrate that DS-8201a will be a valuable therapy with a great potential to respond to T-DM1-insensitive HER2-positive cancers and low HER2-expressing cancers. Clin Cancer Res; 22(20); 5097-108. ©2016 AACR. ©2016 American Association for Cancer Research.

  19. Human Monoclonal Islet Cell Antibodies From a Patient with Insulin- Dependent Diabetes Mellitus Reveal Glutamate Decarboxylase as the Target Antigen

    NASA Astrophysics Data System (ADS)

    Richter, Wiltrud; Endl, Josef; Eiermann, Thomas H.; Brandt, Michael; Kientsch-Engel, Rosemarie; Thivolet, Charles; Jungfer, Herbert; Scherbaum, Werner A.

    1992-09-01

    The autoimmune phenomena associated with destruction of the β cell in pancreatic islets and development of type 1 (insulin-dependent) diabetes mellitus (IDDM) include circulating islet cell antibodies. We have immortalized peripheral blood lymphocytes from prediabetic individuals and patients with newly diagnosed IDDM by Epstein-Barr virus transformation. IgG-positive cells were selected by anti-human IgG-coupled magnetic beads and expanded in cell culture. Supernatants were screened for cytoplasmic islet cell antibodies using the conventional indirect immunofluorescence test on cryostat sections of human pancreas. Six islet cell-specific B-cell lines, originating from a patient with newly diagnosed IDDM, could be stabilized on a monoclonal level. All six monoclonal islet cell antibodies (MICA 1-6) were of the IgG class. None of the MICA reacted with human thyroid, adrenal gland, anterior pituitary, liver, lung, stomach, and intestine tissues but all six reacted with pancreatic islets of different mammalian species and, in addition, with neurons of rat cerebellar cortex. MICA 1-6 were shown to recognize four distinct antigenic epitopes in islets. Islet cell antibody-positive diabetic sera but not normal human sera blocked the binding of the monoclonal antibodies to their target epitopes. Immunoprecipitation of 35S-labeled human islet cell extracts revealed that a protein of identical size to the enzyme glutamate decarboxylase (EC 4.1.1.15) was a target of all MICA. Furthermore, antigen immunotrapped by the MICA from brain homogenates showed glutamate decarboxylase enzyme activity. MICA 1-6 therefore reveal glutamate decarboxylase as the predominant target antigen of cytoplasmic islet cell autoantibodies in a patient with newly diagnosed IDDM.

  20. HER2 and β-catenin protein location: importance in the prognosis of breast cancer patients and their correlation when breast cancer cells suffer stressful situations.

    PubMed

    Cuello-Carrión, F Darío; Shortrede, Jorge E; Alvarez-Olmedo, Daiana; Cayado-Gutiérrez, Niubys; Castro, Gisela N; Zoppino, Felipe C M; Guerrero, Martín; Martinis, Estefania; Wuilloud, Rodolfo; Gómez, Nidia N; Biaggio, Verónica; Orozco, Javier; Gago, Francisco E; Ciocca, Leonardo A; Fanelli, Mariel A; Ciocca, Daniel R

    2015-02-01

    In human breast cancer, β-catenin localization has been related with disease prognosis. Since HER2-positive patients are an important subgroup, and that in breast cancer cells a direct interaction of β-catenin/HER2 has been reported, in the present study we have explored whether β-catenin location is related with the disease survival. The study was performed in a tumor bank from patients (n = 140) that did not receive specific anti-HER2 therapy. The proteins were detected by immunohistochemistry in serial sections, 47 (33.5%) patients were HER2-positive with a long follow-up. HER2-positive patients that displayed β-catenin at the plasma membrane (completely surrounding the tumour cells) showed a significant better disease-free survival and overall survival than the patients showing the protein on other locations. Then we explored the dynamics of the co-expression of β-catenin and HER2 in human MCF-7 and SKBR3 cells exposed to different stressful situations. In untreated conditions MCF-7 and SKBR3 cells showed very different β-catenin localization. In MCF-7 cells, cadmium administration caused a striking change in β-catenin localization driving it from plasma membrane to cytoplasmic and perinuclear areas and HER2 showed a similar localization patterns. The changes induced by cadmium were compared with heat shock, H2O2 and tamoxifen treatments. In conclusion, this study shows the dynamical associations of HER2 and β-catenin and their changes in subcellular localizations driven by stressful situations. In addition, we report for the first time the correlation between plasma membrane associated β-catenin in HER2-positive breast cancer and survival outcome, and the importance of the protein localization in breast cancer samples.

  1. Upbeat nystagmus in anti-Ma2 encephalitis.

    PubMed

    Garcia-Reitboeck, Pablo; Thompson, Graham; Johns, Paul; Al Wahab, Yasir; Omer, Salah; Griffin, Colette

    2014-02-01

    Anti-Ma2 encephalitis is a paraneoplastic disorder characterised by brainstem and/or limbic involvement. Eye movement abnormalities can occur in this condition, often with confusion or somnolence. We describe a patient with progressive oscillopsia (with upbeat nystagmus) and unsteadiness, followed by acute pancreatitis. She did not respond to immunomodulatory treatment and subsequently died of complications related to pancreatitis and sepsis. There was no tumour identified at autopsy, but the anti-Ma2 antibodies in her serum and the discovery of a brainstem-predominant inflammatory infiltrate at autopsy strongly suggest a paraneoplastic disorder. Our case illustrates that upbeat nystagmus can be a predominant feature in anti-Ma2 encephalitis; clinicians should consider testing for anti-Ma2 antibodies in patients with upbeat nystagmus of unknown cause.

  2. Dual-Labeled Near-Infrared/99mTc Imaging Probes Using PAMAM-Coated Silica Nanoparticles for the Imaging of HER2-Expressing Cancer Cells

    PubMed Central

    Yamaguchi, Haruka; Tsuchimochi, Makoto; Hayama, Kazuhide; Kawase, Tomoyuki; Tsubokawa, Norio

    2016-01-01

    We sought to develop dual-modality imaging probes using functionalized silica nanoparticles to target human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer cells and achieve efficient target imaging of HER2-expressing tumors. Polyamidoamine-based functionalized silica nanoparticles (PCSNs) for multimodal imaging were synthesized with near-infrared (NIR) fluorescence (indocyanine green (ICG)) and technetium-99m (99mTc) radioactivity. Anti-HER2 antibodies were bound to the labeled PCSNs. These dual-imaging probes were tested to image HER2-overexpressing breast carcinoma cells. In vivo imaging was also examined in breast tumor xenograft models in mice. SK-BR3 (HER2 positive) cells were imaged with stronger NIR fluorescent signals than that in MDA-MB231 (HER2 negative) cells. The increased radioactivity of the SK-BR3 cells was also confirmed by phosphor imaging. NIR images showed strong fluorescent signals in the SK-BR3 tumor model compared to muscle tissues and the MDA-MB231 tumor model. Automatic well counting results showed increased radioactivity in the SK-BR3 xenograft tumors. We developed functionalized silica nanoparticles loaded with 99mTc and ICG for the targeting and imaging of HER2-expressing cells. The dual-imaging probes efficiently imaged HER2-overexpressing cells. Although further studies are needed to produce efficient isotope labeling, the results suggest that the multifunctional silica nanoparticles are a promising vehicle for imaging specific components of the cell membrane in a dual-modality manner. PMID:27399687

  3. Dual-Labeled Near-Infrared/(99m)Tc Imaging Probes Using PAMAM-Coated Silica Nanoparticles for the Imaging of HER2-Expressing Cancer Cells.

    PubMed

    Yamaguchi, Haruka; Tsuchimochi, Makoto; Hayama, Kazuhide; Kawase, Tomoyuki; Tsubokawa, Norio

    2016-07-07

    We sought to develop dual-modality imaging probes using functionalized silica nanoparticles to target human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer cells and achieve efficient target imaging of HER2-expressing tumors. Polyamidoamine-based functionalized silica nanoparticles (PCSNs) for multimodal imaging were synthesized with near-infrared (NIR) fluorescence (indocyanine green (ICG)) and technetium-99m ((99m)Tc) radioactivity. Anti-HER2 antibodies were bound to the labeled PCSNs. These dual-imaging probes were tested to image HER2-overexpressing breast carcinoma cells. In vivo imaging was also examined in breast tumor xenograft models in mice. SK-BR3 (HER2 positive) cells were imaged with stronger NIR fluorescent signals than that in MDA-MB231 (HER2 negative) cells. The increased radioactivity of the SK-BR3 cells was also confirmed by phosphor imaging. NIR images showed strong fluorescent signals in the SK-BR3 tumor model compared to muscle tissues and the MDA-MB231 tumor model. Automatic well counting results showed increased radioactivity in the SK-BR3 xenograft tumors. We developed functionalized silica nanoparticles loaded with (99m)Tc and ICG for the targeting and imaging of HER2-expressing cells. The dual-imaging probes efficiently imaged HER2-overexpressing cells. Although further studies are needed to produce efficient isotope labeling, the results suggest that the multifunctional silica nanoparticles are a promising vehicle for imaging specific components of the cell membrane in a dual-modality manner.

  4. Trastuzumab has preferential activity against breast cancers driven by HER2 homodimers

    PubMed Central

    Ghosh, Ritwik; Narasanna, Archana; Wang, Shizhen Emily; Liu, Shuying; Chakrabarty, Anindita; Balko, Justin M.; González-Angulo, Ana María; Mills, Gordon B.; Penuel, Elicia; Winslow, John; Sperinde, Jeff; Dua, Rajiv; Pidaparthi, Sailaja; Mukherjee, Ali; Leitzel, Kim; Kostler, Wolfgang J.; Lipton, Allan; Bates, Michael; Arteaga, Carlos L.

    2011-01-01

    In breast cancer cells with HER2 gene amplification, HER2 receptors exist on the cell surface as monomers, homodimers and heterodimers with EGFR/HER3. The therapeutic antibody trastuzumab, an approved therapy for HER2+ breast cancer, cannot block ligand-induced HER2 heterodimers, suggesting it cannot effectively inhibit HER2 signaling. Hence, HER2 oligomeric states may predict the odds of a clinical response to trastuzumab in HER2-driven tumors. To test this hypothesis, we generated non-transformed human MCF10A mammary epithelial cells stably expressing a chimeric HER2-FKBP molecule that could be conditionally induced to homodimerize by adding the FKBP ligand AP1510, or instead induced to heterodimerize with EGFR or HER3 by adding the heterodimer ligands EGF/TGFα or heregulin. AP1510, EGF, and heregulin each induced growth of MCF10A cells expressing HER2-FKBP. As expected, trastuzumab inhibited homodimer-mediated but not heterodimer-mediated cell growth. In contrast, the HER2 antibody pertuzumab, which blocks HER2 heterodimerization, inhibited growth induced by heregulin but not AP1510. Lastly, HER2/EGFR tyrosine kinase inhibitor lapatinib blocked both homodimer- and heterodimer-induced growth. AP1510 triggered phosphorylation of Erk1/2 but not AKT, whereas trastuzumab inhibited AP1510-induced Erk1/2 phosphorylation and Shc-HER2 homodimer binding, but not TGFα-induced AKT phosphorylation. Consistent with these observations, high levels of HER2 homodimers correlated with longer time to progression following trastuzumab therapy in a cohort of HER2-overexpressing patients. Together, our findings corroborate the hypothesis that HER2 oligomeric states regulate HER2 signaling, also arguing that trastuzumab sensitivity of homodimers reflects an inability to activate the PI3K/AKT pathway. One of the most important clinical implications of our results is that high levels of HER2 homodimers may predict a positive response to trastuzumab. PMID:21324925

  5. Closing the Personalized Medicine Information Gap: HER2 Test Documentation Practice

    PubMed Central

    Ferrusi, Ilia L.; Earle, Craig C.; Trudeau, Maureen; Leighl, Natasha B.; Pullenayegum, Eleanor; Khong, Hoa; Hoch, Jeffrey S.; Marshall, Deborah A.

    2013-01-01

    Background Uncertainty about human epidermal growth factor receptor-2 (HER2) testing practice in Canada continues to hinder efforts to improve personalized medicine. Pathologists routinely perform HER2 assessment for all tumors > 1 cm, and pathology is reported centrally to the provincial cancer registry. Objectives To understand patterns of HER2 test documentation for early-stage breast cancer (BC) patients in Ontario’s centralized pathology reporting system. Study Design Retrospective cohort study of central HER2 test documentation in early-stage BC patients diagnosed in 2006–2007. Methods Cohort and staging information was derived from cancer registry and admissions data. Linkage across administrative databases provided data on surgical and radiologic treatment, sociodemographic factors, diagnosis setting, and comorbidities. Pathology reports from the provincial cancer registry were reviewed for HER2 testing, hormone receptor, and grade. Unadjusted and adjusted odds ratios were calculated to determine factors related to HER2 documentation. Results A HER2 test was documented for 66% of 13,396 patients. HER2 documentation was associated with stage, hormone receptor, and tumor grade documentation. Higher stage and grade at diagnosis were also associated with HER2 documentation. All models suggested variable regional documentation patterns. Documentation did not differ by sociodemographic factors, presence of comorbidities, or surgical procedure. Conclusions Despite a universal testing policy, the rate of centralized HER2 test documentation was lower than expected and related to disease severity. Differences in regional reporting likely reflect ascertainment bias inherent to centralized pathology reporting rather than testing access. Improved HER2 reporting is encouraged for cancer registration, quality-of-care measurement, and program evaluation. PMID:23379747

  6. The extracellular domain of Her2 in serum as a biomarker of breast cancer.

    PubMed

    Perrier, Alexandre; Gligorov, Joseph; Lefèvre, Guillaume; Boissan, Mathieu

    2018-02-28

    Breast cancer is a major health problem worldwide. In ~15% of breast cancers, the epidermal growth factor receptor HER2, a transmembrane protein, is overexpressed. This HER2 overexpression is associated with an aggressive form of the disease and a poor clinical prognosis. The extracellular domain (ECD) of HER2 is released into the blood by a proteolytic mechanism known as "ECD shedding". This proteolytic shedding leaves a constitutively active truncated receptor in the membrane that is 10-100-fold more oncogenic than the full-length receptor and promotes the growth and survival of cancer cells. Shedding of the HER2 ECD is increased during metastasis: whereas 15% of primary breast cancer patients have elevated levels of serum HER2 ECD (sHER2 ECD), the levels reach 45% in patients with metastatic disease. Thus, sHER2 ECD has been proposed as a promising biomarker for cancer recurrence and for monitoring the disease status of patients overexpressing HER2. Nevertheless, in 2016, the American Society of Clinical Oncology advises clinicians not to use soluble HER2 levels to guide their choice of adjuvant therapy for patients with HER2-positive breast cancer, because the evidence was considered not strong enough. Currently, biomarkers such as carcinoembryonic antigen and cancer antigen 15-3 are widely used to monitor metastatic breast cancer disease even if the level of evidence of clinical impact of this monitoring is poor. In this article, we review the evidence that sHER2 ECD might be used in some situations as a biomarker for breast cancer. Although this serum biomarker will not replace the direct measurement of tumor HER2 status for diagnosis of early-stage tumors; it might be especially useful in metastatic disease for prognosis, as an indicator of cancer progression and of therapy response, particularly to anti-HER2 therapies. Owing to these data, sHER2 ECD should be considered as a promising biomarker to detect cancer recurrence and metastasis.

  7. Novel Cross-Reactive Monoclonal Antibodies against Ebolavirus Glycoproteins Show Protection in a Murine Challenge Model.

    PubMed

    Duehr, James; Wohlbold, Teddy John; Oestereich, Lisa; Chromikova, Veronika; Amanat, Fatima; Rajendran, Madhusudan; Gomez-Medina, Sergio; Mena, Ignacio; tenOever, Benjamin R; García-Sastre, Adolfo; Basler, Christopher F; Munoz-Fontela, Cesar; Krammer, Florian

    2017-08-15

    Out of an estimated 31,100 cases since their discovery in 1976, ebolaviruses have caused approximately 13,000 deaths. The vast majority (∼11,000) of these occurred during the 2013-2016 West African epidemic. Three out of five species in the genus are known to cause Ebola Virus Disease in humans. Several monoclonal antibodies against the ebolavirus glycoprotein are currently in development as therapeutics. However, there is still a paucity of monoclonal antibodies that can cross-react between the glycoproteins of different ebolavirus species, and the mechanism of these monoclonal antibody therapeutics is still not understood in detail. Here, we generated a panel of eight murine monoclonal antibodies (MAbs) utilizing a prime-boost vaccination regimen with a Zaire ebolavirus glycoprotein expression plasmid followed by infection with a vesicular stomatitis virus expressing the Zaire ebolavirus glycoprotein. We tested the binding breadth of the resulting monoclonal antibodies using a set of recombinant surface glycoproteins from Reston, Taï Forest, Bundibugyo, Zaire, Sudan, and Marburg viruses and found two antibodies that showed pan-ebolavirus binding. An in vivo Stat2 -/- mouse model was utilized to test the ability of these MAbs to protect from infection with a vesicular stomatitis virus expressing the Zaire ebolavirus glycoprotein. Several of our antibodies, including the broadly binding ones, protected mice from mortality despite lacking neutralization capability in vitro , suggesting their protection may be mediated by Fc-FcR interactions. Indeed, three antibodies displayed cellular phagocytosis and/or antibody-dependent cell-mediated cytotoxicity in vitro Our antibodies, specifically the two identified cross-reactive monoclonal antibodies (KL-2E5 and KL-2H7), might add to the understanding of anti-ebolavirus humoral immunity. IMPORTANCE This study describes the generation of a panel of novel anti-ebolavirus glycoprotein monoclonal antibodies, including two

  8. Novel Cross-Reactive Monoclonal Antibodies against Ebolavirus Glycoproteins Show Protection in a Murine Challenge Model

    PubMed Central

    Duehr, James; Wohlbold, Teddy John; Oestereich, Lisa; Chromikova, Veronika; Amanat, Fatima; Gomez-Medina, Sergio; Mena, Ignacio; tenOever, Benjamin R.; García-Sastre, Adolfo; Basler, Christopher F.

    2017-01-01

    ABSTRACT Out of an estimated 31,100 cases since their discovery in 1976, ebolaviruses have caused approximately 13,000 deaths. The vast majority (∼11,000) of these occurred during the 2013-2016 West African epidemic. Three out of five species in the genus are known to cause Ebola Virus Disease in humans. Several monoclonal antibodies against the ebolavirus glycoprotein are currently in development as therapeutics. However, there is still a paucity of monoclonal antibodies that can cross-react between the glycoproteins of different ebolavirus species, and the mechanism of these monoclonal antibody therapeutics is still not understood in detail. Here, we generated a panel of eight murine monoclonal antibodies (MAbs) utilizing a prime-boost vaccination regimen with a Zaire ebolavirus glycoprotein expression plasmid followed by infection with a vesicular stomatitis virus expressing the Zaire ebolavirus glycoprotein. We tested the binding breadth of the resulting monoclonal antibodies using a set of recombinant surface glycoproteins from Reston, Taï Forest, Bundibugyo, Zaire, Sudan, and Marburg viruses and found two antibodies that showed pan-ebolavirus binding. An in vivo Stat2−/− mouse model was utilized to test the ability of these MAbs to protect from infection with a vesicular stomatitis virus expressing the Zaire ebolavirus glycoprotein. Several of our antibodies, including the broadly binding ones, protected mice from mortality despite lacking neutralization capability in vitro, suggesting their protection may be mediated by Fc-FcR interactions. Indeed, three antibodies displayed cellular phagocytosis and/or antibody-dependent cell-mediated cytotoxicity in vitro. Our antibodies, specifically the two identified cross-reactive monoclonal antibodies (KL-2E5 and KL-2H7), might add to the understanding of anti-ebolavirus humoral immunity. IMPORTANCE This study describes the generation of a panel of novel anti-ebolavirus glycoprotein monoclonal antibodies

  9. HER2-induced metastasis is mediated by AKT/JNK/EMT signaling pathway in gastric cancer

    PubMed Central

    Choi, Yiseul; Ko, Young San; Park, Jinju; Choi, Youngsun; Kim, Younghoon; Pyo, Jung-Soo; Jang, Bo Gun; Hwang, Douk Ho; Kim, Woo Ho; Lee, Byung Lan

    2016-01-01

    AIM To investigated the relationships between HER2, c-Jun N-terminal kinase (JNK) and protein kinase B (AKT) with respect to metastatic potential of HER2-positive gastric cancer (GC) cells. METHODS Immunohistochemistry was performed on tissue array slides containing 423 human GC specimens. Using HER2-positve GC cell lines SNU-216 and NCI-N87, HER2 expression was silenced by RNA interference, and the activations of JNK and AKT were suppressed by SP600125 and LY294002, respectively. Transwell assay, Western blot, semi-quantitative reverse transcription-polymerase chain reaction and immunofluorescence staining were used in cell culture experiments. RESULTS In GC specimens, HER2, JNK, and AKT activations were positively correlated with each other. In vitro analysis revealed a positive regulatory feedback loop between HER2 and JNK in GC cell lines and the role of JNK as a downstream effector of AKT in the HER2/AKT signaling pathway. JNK inhibition suppressed migratory capacity through reversing EMT and dual inhibition of JNK and AKT induced a more profound effect on cancer cell motility. CONCLUSION HER2, JNK and AKT in human GC specimens are positively associated with each other. JNK and AKT, downstream effectors of HER2, co-operatively contribute to the metastatic potential of HER2-positive GC cells. Thus, targeting of these two molecules in combination with HER2 downregulation may be a good approach to combat HER2-positive GC. PMID:27895401

  10. Generation and Characterization of Anti-CD34 Monoclonal Antibodies that React with Hematopoietic Stem Cells

    PubMed Central

    Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Movassaghpour, Aliakbar; Abdolalizadeh, Jalal

    2014-01-01

    CD34 is a type I membrane protein with a molecular mass of approximately 110 kDa. This antigen is associated with human hematopoietic progenitor cells and is a differentiation stage-specific leukocyte antigen. In this study we have generated and characterized monoclonal antibodies (mAbs) directed against a CD34 marker. Mice were immunized with two keyhole lympet hemocyanin (KLH)-conjugated CD34 peptides. Fused cells were grown in hypoxanthine, aminopterine and thymidine (HAT) selective medium and cloned by the limiting dilution (L.D) method. Several monoclones were isolated by three rounds of limited dilutions. From these, we chose stable clones that presented sustained antibody production for subsequent characterization. Antibodies were tested for their reactivity and specificity to recognize the CD34 peptides and further screened by enzyme-linked immunosorbent assay (ELISA) and Western blotting analyses. One of the mAbs (3D5) was strongly reactive against the CD34 peptide and with native CD34 from human umbilical cord blood cells (UCB) in ELISA and Western blotting analyses. The results have shown that this antibody is highly specific and functional in biomedical applications such as ELISA and Western blot assays. This monoclonal antibodies (mAb) can be a useful tool for isolation and purification of human hematopoietic stem cells (HSCs). PMID:24611141

  11. Adjuvant Trastuzumab in HER2-Positive Early Breast Cancer by Age and Hormone Receptor Status: A Cost-Utility Analysis.

    PubMed

    Leung, William; Kvizhinadze, Giorgi; Nair, Nisha; Blakely, Tony

    2016-08-01

    The anti-human epidermal growth factor receptor 2 (HER2) monoclonal antibody trastuzumab improves outcomes in patients with node-positive HER2+ early breast cancer. Given trastuzumab's high cost, we aimed to estimate its cost-effectiveness by heterogeneity in age and estrogen receptor (ER) and progesterone receptor (PR) status, which has previously been unexplored, to assist prioritisation. A cost-utility analysis was performed using a Markov macro-simulation model, with a lifetime horizon, comparing a 12-mo regimen of trastuzumab with chemotherapy alone using the latest (2014) effectiveness measures from landmark randomised trials. A New Zealand (NZ) health system perspective was adopted, employing high-quality national administrative data. Incremental quality-adjusted life-years for trastuzumab versus chemotherapy alone are two times higher (2.33 times for the age group 50-54 y; 95% CI 2.29-2.37) for the worst prognosis (ER-/PR-) subtype compared to the best prognosis (ER+/PR+) subtype, causing incremental cost-effectiveness ratios (ICERs) for the former to be less than half those of the latter for the age groups from 25-29 to 90-94 y (0.44 times for the age group 50-54 y; 95% CI 0.43-0.45). If we were to strictly apply an arbitrary cost-effectiveness threshold equal to the NZ gross domestic product per capita (2011 purchasing power parity [PPP]-adjusted: US$30,300; €23,700; £21,200), our study suggests that trastuzumab (2011 PPP-adjusted US$45,400/€35,900/£21,900 for 1 y at formulary prices) may not be cost-effective for ER+ (which are 61% of all) node-positive HER2+ early breast cancer patients but cost-effective for ER-/PR- subtypes (37% of all cases) to age 69 y. Market entry of trastuzumab biosimilars will likely reduce the ICER to below this threshold for premenopausal ER+/PR- cancer but not for ER+/PR+ cancer. Sensitivity analysis using the best-case effectiveness measure for ER+ cancer had the same result. A key limitation was a lack of treatment

  12. Potent Inhibition of Human Immunodeficiency Virus Type 1 Replication by an Intracellular Anti-Rev Single-Chain Antibody

    NASA Astrophysics Data System (ADS)

    Duan, Lingxun; Bagasra, Omar; Laughlin, Mark A.; Oakes, Joseph W.; Pomerantz, Roger J.

    1994-05-01

    Human immunodeficiency virus type 1 (HIV-1) has a complex life cycle, which has made it a difficult target for conventional therapeutic modalities. A single-chain antibody moiety, directed against the HIV-1 regulatory protein Rev, which rescues unspliced viral RNA from the nucleus of infected cells, has now been developed. This anti-Rev single-chain construct (SFv) consists of both light and heavy chain variable regions of an anti-Rev monoclonal antibody, which, when expressed intracellularly within human cells, potently inhibits HIV-1 replication. This intracellular SFv molecule is demonstrated to specifically antagonize Rev function. Thus, intracellular SFv expression, against a retroviral regulatory protein, may be useful as a gene therapeutic approach to combat HIV-1 infections.

  13. Cytotoxic effect of the Her-2/Her-1 inhibitor PKI-166 on renal cancer cells expressing the connexin 32 gene.

    PubMed

    Fujimoto, Eriko; Yano, Tomohiro; Sato, Hiromi; Hagiwara, Kiyokazu; Yamasaki, Hiroshi; Shirai, Sumiko; Fukumoto, Keiko; Hagiwara, Hiromi; Negishi, Etsuko; Ueno, Koichi

    2005-02-01

    We have reported that connexin (Cx) 32 acts as a tumor suppressor gene in renal cancer cells partly due to Her-2 inactivation. Here, we determined if a Her-2/Her-1 inhibitor (PKI-166) can enhance the tumor-suppressive effect of Cx32 in Caki-2 cells from human renal cell carcinoma. The expression of Cx32 in Caki-2 cells was required for PKI-166-induced cytotoxic effect at lower doses. The cyctotoxicity was dependent on the occurrence of apoptosis and partly mediated by Cx32-driven gap junction intercellular communications. These results suggest that PKI-166 further supports the tumor-suppressive effect of the Cx32 gene in renal cancer cells through the induction of apoptosis.

  14. Preoperative serum HER2 extracellular domain levels in primary invasive breast cancer.

    PubMed

    Lee, Sae Byul; Lee, Jong Won; Yu, Jong Han; Ko, Beom Seok; Kim, Hee Jeong; Son, Byung Ho; Gong, Gyungyub; Lee, Hee Jin; Kim, Sung-Bae; Jung, Kyung Hae; Ahn, Jin-Hee; Lee, Woochang; Sung, Joohon; Ahn, Sei-Hyun

    2014-12-10

    Despite the preclinical outcomes and biologic significance of the presence of the human epidermal growth factor receptor-2 (HER2) extracellular domain (ECD), there is little evidence supporting the measurement of ECD levels in any clinical setting. The aim of this study was to determine the prevalence of elevated serum HER2 ECD levels, the association between these levels and tissue HER2 overexpression, and the potential clinical prognostic value of HER2 ECD in primary invasive breast cancer. Serum HER2 ECD levels were examined preoperatively in 2,862 consecutive stage I-III primary breast cancer patients between 2007 and 2009. Serum HER2 ECD levels were measured by chemiluminescence immunoassay (ADVIA Centaur), and the tissue HER2 status was assessed by immunohistochemistry and fluorescence in situ hybridization. The cutoff value for the serum level of HER2 ECD was set at 15.2 ng/ml. Among the 2,862 patients, 126 (4.4%) had elevated serum HER2 ECD levels, and HER2 was overexpressed in the tumor tissue of 692 patients (24.2%), with a concordance of 78.7%. Multivariate analysis revealed that elevated serum HER2 ECD was a significant independent prognostic factor for worse distant-metastasis-free survival [DMFS; hazard ratio (HR) = 2.50, 95% confidence interval (CI) = 1.5-4.3, P = 0.001] and breast-cancer-specific survival (BCSS; HR = 2.0, 95% CI = 1.1-3.8, P = 0.036), which were much stronger in patients with tissue HER2-positive tumors (DMFS: HR = 3.8, 95% CI = 2.0-7.0, P < 0.001; BCSS: HR = 2.6, 95% CI = 1.2-5.3, P = 0.012). Given the prevalence of HER2 expression, its measurement as an independent prognostic factor can be clinically useful, particularly in patients with tissue HER2-positive tumors.

  15. A HER2-specific Modified Fc Fragment (Fcab) Induces Antitumor Effects Through Degradation of HER2 and Apoptosis

    PubMed Central

    Leung, Kin-Mei; Batey, Sarah; Rowlands, Robert; Isaac, Samine J; Jones, Phil; Drewett, Victoria; Carvalho, Joana; Gaspar, Miguel; Weller, Sarah; Medcalf, Melanie; Wydro, Mateusz M; Pegram, Robert; Mudde, Geert C; Bauer, Anton; Moulder, Kevin; Woisetschläger, Max; Tuna, Mihriban; Haurum, John S; Sun, Haijun

    2015-01-01

    FS102 is a HER2-specific Fcab (Fc fragment with antigen binding), which binds HER2 with high affinity and recognizes an epitope that does not overlap with those of trastuzumab or pertuzumab. In tumor cells that express high levels of HER2, FS102 caused profound HER2 internalization and degradation leading to tumor cell apoptosis. The antitumor effect of FS102 in patient-derived xenografts (PDXs) correlated strongly with the HER2 amplification status of the tumors. Superior activity of FS102 over trastuzumab or the combination of trastuzumab and pertuzumab was observed in vitro and in vivo when the gene copy number of HER2 was equal to or exceeded 10 per cell based on quantitative polymerase chain reaction (qPCR). Thus, FS102 induced complete and sustained tumor regression in a significant proportion of HER2-high PDX tumor models. We hypothesize that the unique structure and/or epitope of FS102 enables the Fcab to internalize and degrade cell surface HER2 more efficiently than standard of care antibodies. In turn, increased depletion of HER2 commits the cells to apoptosis as a result of oncogene shock. FS102 has the potential of a biomarker-driven therapeutic that derives superior antitumor effects from a unique mechanism-of-action in tumor cells which are oncogenically addicted to the HER2 pathway due to overexpression. PMID:26234505

  16. Attaching quantum dots to HER2 specific phage antibodies

    NASA Astrophysics Data System (ADS)

    Chu, Viet Ha; Nghiem, Thi Ha Lien; Huyen La, Thi; Dieu Thuy Ung, Thi; Huan Le, Quang; Thuan Tong, Kim; Liem Nguyen, Quang; Nhung Tran, Hong

    2010-06-01

    This work presents the results of the attachment of Qdot 655 ITKTM amino (PEG) quantum dots (QDs) (Invitrogen) and CdTe QDs (provided by Institute of Materials Science, VAST) to HER2 (Human Epidermal growth factor Receptor 2) specific phage antibodies (Abs) (provided by Institute of Biotechnology, VAST) in solution. The QDs were attached to the phage display specific HER2 Abs to form a complex QD-Ab. The QDs and complex QD-Ab were characterized by UV-VIS spectroscopy, transmission electron microscopy (TEM) and fluorescence microscopy. The fluorescence images show the QDs conjugated to the phage. Due to the QDs attaching to the surface, the phage dimensions were amplified, so its shape could be observed by optical microscopy. The complex QD-Ab was stable and lasted for a month. The results illustrate the value of the HER2 phage-QD complex as a cancer detection platform.

  17. Phase III, Randomized Study of Dual Human Epidermal Growth Factor Receptor 2 (HER2) Blockade With Lapatinib Plus Trastuzumab in Combination With an Aromatase Inhibitor in Postmenopausal Women With HER2-Positive, Hormone Receptor-Positive Metastatic Breast Cancer: ALTERNATIVE.

    PubMed

    Johnston, Stephen R D; Hegg, Roberto; Im, Seock-Ah; Park, In Hae; Burdaeva, Olga; Kurteva, Galina; Press, Michael F; Tjulandin, Sergei; Iwata, Hiroji; Simon, Sergio D; Kenny, Sarah; Sarp, Severine; Izquierdo, Miguel A; Williams, Lisa S; Gradishar, William J

    2018-03-10

    Purpose Human epidermal growth factor receptor 2 (HER2) targeting plus endocrine therapy (ET) improved clinical benefit in HER2-positive, hormone receptor (HR)-positive metastatic breast cancer (MBC) versus ET alone. Dual HER2 blockade enhances clinical benefit versus single HER2 blockade. The ALTERNATIVE study evaluated the efficacy and safety of dual HER2 blockade plus aromatase inhibitor (AI) in postmenopausal women with HER2-positive/HR-positive MBC who received prior ET and prior neo(adjuvant)/first-line trastuzumab (TRAS) plus chemotherapy. Methods Patients were randomly assigned (1:1:1) to receive lapatinib (LAP) + TRAS + AI, TRAS + AI, or LAP + AI. Patients for whom chemotherapy was intended were excluded. The primary end point was progression-free survival (PFS; investigator assessed) with LAP + TRAS + AI versus TRAS + AI. Secondary end points were PFS (comparison of other arms), overall survival, overall response rate, clinical benefit rate, and safety. Results Three hundred fifty-five patients were included in this analysis: LAP + TRAS + AI (n = 120), TRAS + AI (n = 117), and LAP + AI (n = 118). Baseline characteristics were balanced. The study met its primary end point; superior PFS was observed with LAP + TRAS + AI versus TRAS + AI (median PFS, 11 v 5.7 months; hazard ratio, 0.62; 95% CI, 0.45 to 0.88; P = .0064). Consistent PFS benefit was observed in predefined subgroups. Overall response rate, clinical benefit rate, and overall survival also favored LAP + TRAS + AI. The median PFS with LAP + AI versus TRAS + AI was 8.3 versus 5.7 months (hazard ratio, 0.71; 95% CI, 0.51 to 0.98; P = .0361). Common adverse events (AEs; ≥ 15%) with LAP + TRAS + AI, TRAS + AI, and LAP + AI were diarrhea (69%, 9%, and 51%, respectively), rash (36%, 2%, and 28%, respectively), nausea (22%, 9%, and 22%, respectively), and paronychia (30%, 0%, and 15%, respectively), mostly grade 1 or 2. Serious AEs were reported similarly across the three groups, and AEs leading to

  18. Acute neurological worsening after Rituximab treatment in patients with anti-MAG neuropathy.

    PubMed

    Sala, Emilie; Robert-Varvat, Florence; Paul, Stéphane; Camdessanché, Jean-Philippe; Antoine, Jean-Christophe

    2014-10-15

    Patients with peripheral neuropathy and anti-MAG monoclonal IgM may respond to Rituximab, a humanized monoclonal anti-CD20 antibody. We report on three patients with peripheral neuropathy and anti-MAG monoclonal IgM who deteriorated under Rituximab and reviewed seven previously published cases. Worsening was acute and severe, and occurred during the treatment period. All the patients improved after deterioration but at final evaluation only one was improved comparatively to baseline, five were worsened and four were stabilized. Deterioration was not clearly associated with an increase of the anti-MAG antibody titer. Two patients received Rituximab prior or after the course which induced worsening without adverse reaction. Although rare, acute worsening of the neuropathy can occur after Rituximab. The deterioration is however reversible within some weeks to several months. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. An improved radiolabelled RNA aptamer molecule for HER2 imaging in cancers.

    PubMed

    Varmira, Kambiz; Hosseinimehr, Seyed Jalal; Noaparast, Zohreh; Abedi, Seyed Mohammad

    2014-02-01

    Human epidermal growth factor receptor 2 (HER2) expression has been shown to be increased in several types of human tumours. In this study, for the imaging of HER2-related tumours, a modified RNA aptamer with HER2-specific targeting was labelled with (99m)Tc, by using hydrazino nicotinamide (HYNIC) as the chelator in the presence of tricine or ethylenediamine-N,N'-diacetic acid (EDDA) as the co-ligand. Stability testing of the radiolabelled aptamers in the serum was performed through SDS-PAGE. The aptamer-radionuclide conjugate was evaluated for its cellular HER2-specific binding in ovarian cancer cells (SKOV-3), and its biodistribution properties were assessed in normal and SKOV-3 tumour-bearing mice. In the presence of either tricine or EDDA, the HYNIC-RNA aptamers were labelled with (99m)Tc at a high yield and radiochemical purity. Cellular experiments confirmed the specific binding of the RNA aptamer to the HER2 receptor. In the animal biodistribution study, uptake of the EDDA-co-liganded (99m)Tc-HYNIC-RNA aptamer by the liver and spleen was remarkably lower than that of the aptamer with tricine. Tumours also showed a higher accumulation of radioactivity with the EDDA-co-liganded aptamer complex. This study demonstrated EDDA to be better than tricine for use as a co-ligand with the RNA aptamer, which can be a potential tool for the molecular imaging of HER2-overexpressing cancers.

  20. Epitope mapping of the gastrin-releasing peptide/anti-bombesin monoclonal antibody complex by proteolysis followed by matrix-assisted laser desorption ionization mass spectrometry.

    PubMed Central

    Papac, D. I.; Hoyes, J.; Tomer, K. B.

    1994-01-01

    We have developed a method to rapidly identify the antigenic determinant for an antibody using in situ proteolysis of an immobilized antigen-antibody complex followed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI/TOF). A mouse anti-bombesin monoclonal antibody was immobilized to agarose beads and then the antigen, gastrin-releasing peptide (GRP), was allowed to bind. Direct analysis of the immobilized antigen-antibody complex by MALDI/TOF is demonstrated and allows identification of ca. 1 pmol of the bound GRP. To identify the epitope, the immobilized antigen-antibody complex was subjected to proteolysis with trypsin, chymotrypsin, thermolysin, and aminopeptidase M. Following proteolysis, the part of the antigen in contact with the antibody and protected from proteolysis was identified directly by MALDI/TOF. Subsequently, the epitope was eluted from the immobilized antibody with 0.1 M glycine buffer (pH 2.3), separated by reversed-phase HPLC, and its identity confirmed by MALDI/TOF. Using this approach, the epitope for the anti-bombesin monoclonal antibody was shown to comprise the last 7-8 residues (HWAVGHLM-NH2) of GRP. PMID:7530543

  1. Antibody treatment of human tumor xenografts elicits active anti-tumor immunity in nude mice

    PubMed Central

    Liebman, Meredith A.; Roche, Marly I.; Williams, Brent R.; Kim, Jae; Pageau, Steven C.; Sharon, Jacqueline

    2007-01-01

    Athymic nude mice bearing subcutaneous tumor xenografts of the human anti-colorectal cancer cell line SW480 were used as a preclinical model to explore anti-tumor immunotherapies. Intratumor or systemic treatment of the mice with murine anti-SW480 serum, recombinant anti-SW480 polyclonal antibodies, or the anti-colorectal cancer monoclonal antibody CO17-1A, caused retardation or regression of SW480 tumor xenografts. Interestingly, when mice that had regressed their tumors were re-challenged with SW480 cells, these mice regressed the new tumors without further antibody treatment. Adoptive transfer of spleen cells from mice that had regressed their tumors conferred anti-tumor immunity to naïve nude mice. Pilot experiments suggest that the transferred anti-tumor immunity is mediated by T cells of both γδ and αβ lineages. These results demonstrate that passive anti-tumor immunotherapy can elicit active immunity and support a role for extra-thymic γδ and αβ T cells in tumor rejection. Implications for potential immunotherapies include injection of tumor nodules in cancer patients with anti-tumor antibodies to induce anti-tumor T cell immunity. PMID:17920694

  2. Influence of DOTA chelator position on biodistribution and targeting properties of (111)In-labeled synthetic anti-HER2 affibody molecules.

    PubMed

    Perols, Anna; Honarvar, Hadis; Strand, Joanna; Selvaraju, Ramkumar; Orlova, Anna; Karlström, Amelie Eriksson; Tolmachev, Vladimir

    2012-08-15

    Affibody molecules are a class of affinity proteins. Their small size (7 kDa) in combination with the high (subnanomolar) affinity for a number of cancer-associated molecular targets makes them suitable for molecular imaging. Earlier studies demonstrated that the selection of radionuclide and chelator may substantially influence the tumor-targeting properties of affibody molecules. Moreover, the placement of chelators for labeling of affibody molecules with (99m)Tc at different positions in affibody molecules influenced both blood clearance rate and uptake in healthy tissues. This introduces an opportunity to improve the contrast of affibody-mediated imaging. In this comparative study, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) was conjugated to the synthetic affibody molecule Z(HER2:S1) at three different positions: DOTA-A1-Z(HER2:S1) (N-terminus), DOTA-K58-Z(HER2:S1) (C-terminus), and DOTA-K50-Z(HER2:S1) (middle of helix 3). The affinity for HER2 differed slightly among the variants and the K(D) values were determined to be 133 pM, 107 pM and 94 pM for DOTA-A1-Z(HER2:S1), DOTA-K50-Z(HER2:S1), and DOTA-K58-Z(HER2:S1), respectively. Z(HER2:S1)-K50-DOTA showed a slightly lower melting point (57 °C) compared to DOTA-A1-Z(HER2:S1) (64 °C) and DOTA-K58-Z(HER2:S1) (62 °C), but all variants showed good refolding properties after heat treatment. All conjugates were successfully labeled with (111)In resulting in a radiochemical yield of 99% with preserved binding capacity. In vitro specificity studies using SKOV-3 and LS174T cell lines showed that the binding of the radiolabeled compounds was HER2 receptor-mediated, which also was verified in vivo using BALB/C nu/nu mice with LS174T and Ramos lymphoma xenografts. The three conjugates all showed specific uptake in LS174T xenografts in nude mice, where DOTA-A1-Z(HER2:S1)and DOTA-K58-Z(HER2:S1) showed the highest uptake. Overall, DOTA-K58-Z(HER2:S1) provided the highest tumor-to-blood ratio, which is

  3. 2-Triazenoazaindoles: A novel class of triazenes inducing transcriptional down-regulation of EGFR and HER-2 in human pancreatic cancer cells

    PubMed Central

    KREUTZER, JAN N.; SALVADOR, ALESSIA; DIANA, PATRIZIA; CIRRINCIONE, GIROLAMO; VEDALDI, DANIELA; LITCHFIELD, DAVID W.; ISSINGER, OLAF-GEORG; GUERRA, BARBARA

    2012-01-01

    Pancreatic cancer is a complex malignancy arising from the accumulation of genetic and epigenetic defects in the affected cells. Standard chemotherapy for patients with advanced disease shows only modest effects and is associated with considerable toxicity. Overexpression or aberrant activation of members of the epidermal growth factor receptor tyrosine kinase family, which includes EGFR and HER-2, occurs frequently and is associated with multiple drug resistance and decreased patient survival. In this study, we have investigated the therapeutic potential of AS104, a novel compound of the triazene class, with potential inhibitory effects on EGFR. We found that treatment of cells with AS104 causes significant reduction of cell growth and metabolic activity in four human pancreatic cancer cell lines. Furthermore, we show that the AS104-mediated induction of apoptotic cell death is associated with stimulation of autophagy in a dose-dependent manner. Treatment of cells with AS104 results in significant down-regulation of EGFR and HER-2 expression and activity and subsequent inhibition of downstream signaling proteins. Quantitative RT-PCR analysis and assays with proteasome inhibitors revealed that AS104 regulates the expression of EGFR and HER-2 at the transcriptional level. These findings provide for the first time experimental evidence for efficacy of AS104 in the simultaneous transcriptional repression of EGFR and HER-2 genes and suggest that AS104 may have therapeutic potential in the treatment of pancreatic cancers that express high levels of the aforementioned receptor tyrosine kinases. PMID:22134789

  4. 2-Triazenoazaindoles: α novel class of triazenes inducing transcriptional down-regulation of EGFR and HER-2 in human pancreatic cancer cells.

    PubMed

    Kreutzer, Jan N; Salvador, Alessia; Diana, Patrizia; Cirrincione, Girolamo; Vedaldi, Daniela; Litchfield, David W; Issinger, Olaf-Georg; Guerra, Barbara

    2012-04-01

    Pancreatic cancer is a complex malignancy arising from the accumulation of genetic and epigenetic defects in the affected cells. Standard chemotherapy for patients with advanced disease shows only modest effects and is associated with considerable toxicity. Overexpression or aberrant activation of members of the epidermal growth factor receptor tyrosine kinase family, which includes EGFR and HER-2, occurs frequently and is associated with multiple drug resistance and decreased patient survival. In this study, we have investigated the therapeutic potential of AS104, a novel compound of the triazene class, with potential inhibitory effects on EGFR. We found that treatment of cells with AS104 causes significant reduction of cell growth and metabolic activity in four human pancreatic cancer cell lines. Furthermore, we show that the AS104-mediated induction of apoptotic cell death is associated with stimulation of autophagy in a dose-dependent manner. Treatment of cells with AS104 results in significant down-regulation of EGFR and HER-2 expression and activity and subsequent inhibition of downstream signaling proteins. Quantitative RT-PCR analysis and assays with proteasome inhibitors revealed that AS104 regulates the expression of EGFR and HER-2 at the transcriptional level. These findings provide for the first time experimental evidence for efficacy of AS104 in the simultaneous transcriptional repression of EGFR and HER-2 genes and suggest that AS104 may have therapeutic potential in the treatment of pancreatic cancers that express high levels of the aforementioned receptor tyrosine kinases.

  5. Liquid-phase electron microscopy of molecular drug response in breast cancer cells reveals irresponsive cell subpopulations related to lack of HER2 homodimers.

    PubMed

    Peckys, Diana B; Korf, Ulrike; Wiemann, Stefan; de Jonge, Niels

    2017-08-09

    The development of drug resistance in cancer poses a major clinical problem. An example is human epidermal growth factor receptor 2 (HER2) overexpressing breast cancer often treated with anti-HER2 antibody therapies, such as trastuzumab. Since drug resistance is rooted mainly in tumor cell heterogeneity, we examined the drug effect in different subpopulations of SKBR3 breast cancer cells, and compared the results with a drug resistant cell line, HCC1954. Correlative light microscopy and liquid-phase scanning transmission electron microscopy (STEM) were used to quantitatively analyze HER2 responses upon drug binding, whereby many tens of whole cells were imaged. Trastuzumab was found to selectively cross-link and down regulate HER2 homodimers from the plasma membranes of bulk cancer cells. In contrast, HER2 resided mainly as monomers in rare subpopulations of resting- and cancer stem cells (CSCs), and these monomers were not internalized after drug binding. The HER2 distribution was hardly influenced by trastuzumab for the HCC1954 cells. These findings show that resting cells and CSCs are irresponsive to the drug, and thus point towards a molecular explanation behind the origin of drug resistance. This analytical method is broadly applicable to study membrane protein interactions in the intact plasma membrane, while accounting for cell heterogeneity. © 2017 by The American Society for Cell Biology.

  6. Rationale and pre-clinical efficacy of a novel anti-EMP2 antibody for the treatment of invasive breast cancer

    PubMed Central

    Fu, Maoyong; Maresh, Erin L.; Helguera, Gustavo F.; Kiyohara, Meagan; Qin, Yu; Ashki, Negin; Daniels-Wells, Tracy R.; Aziz, Najib; Gordon, Lynn K.; Braun, Jonathan; Elshimali, Yahya; Soslow, Robert A.; Penichet, Manuel L.; Goodglick, Lee; Wadehra, Madhuri

    2014-01-01

    Despite significant advances in biology and medicine, the incidence and mortality due to breast cancer world-wide is still unacceptably high. Thus, there is an urgent need to discover new molecular targets. In this paper, we show evidence for a novel target in human breast cancer, the tetraspan protein epithelial membrane protein-2 (EMP2). Using tissue tumor arrays, protein expression of EMP2 was measured and found to be minimal in normal mammary tissue, but it was upregulated in 63% of invasive breast cancer tumors and in 73% of triple negative tumors tested. To test the hypothesis that EMP2 may be a suitable target for therapy, we constructed a fully human IgG1 antibody specific for a conserved domain of human and murine EMP2. Treatment of breast cancer cells with the anti-EMP2 IgG1 significantly inhibited EMP2 mediated signaling, blocked FAK/Src signaling, inhibited invasion, and promoted apoptosis in vitro. In both human xenograft and syngeneic metastatic tumor monotherapy models, anti-EMP2 IgG1 retarded tumor growth without detectable systemic toxicity. This anti-tumor effect was in part attributable to a potent ADCC response as well as direct cytotoxicity induced by the monoclonal antibody. Together, these results identify EMP2 as a novel therapeutic target for invasive breast cancer. PMID:24448822

  7. Development and Characterization of a Novel Anti-idiotypic Monoclonal Antibody to Growth Hormone, Which Can Mimic Physiological Functions of Growth Hormone in Primary Porcine Hepatocytes

    PubMed Central

    Lan, Hai-Nan; Jiang, Hai-Long; Li, Wei; Wu, Tian-Cheng; Hong, Pan; Li, Yu Meng; Zhang, Hui; Cui, Huan-Zhong; Zheng, Xin

    2015-01-01

    B-32 is one of a panel of monoclonal anti-idiotypic antibodies to growth hormone (GH) that we developed. To characterize and identify its potential role as a novel growth hormone receptor (GHR) agonist, we determined that B-32 behaved as a typical Ab2β based on a series of enzyme-linked immunosorbent assay assays. The results of fluorescence-activated cell sorting, indirect immunofluorescence and competitive receptor binding assays demonstrated that B-32 specifically binds to the GHR expressed on target cells. Next, we examined the resulting signal transduction pathways triggered by this antibody in primary porcine hepatocytes. We found that B-32 can activate the GHR and Janus kinase (2)/signal transducers and activators of transcription (JAK2/STAT5) signalling pathways. The phosphorylation kinetics of JAK2/STAT5 induced by either GH or B-32 were analysed in dose-response and time course experiments. In addition, B32 could also stimulate porcine hepatocytes to secrete insulin-like growth factors-1. Our work indicates that a monoclonal anti-idiotypic antibody to GH (B-32) can serve as a GHR agonist or GH mimic and has application potential in domestic animal (pig) production. PMID:25656185

  8. 3D pharmacophore-based virtual screening, docking and density functional theory approach towards the discovery of novel human epidermal growth factor receptor-2 (HER2) inhibitors.

    PubMed

    Gogoi, Dhrubajyoti; Baruah, Vishwa Jyoti; Chaliha, Amrita Kashyap; Kakoti, Bibhuti Bhushan; Sarma, Diganta; Buragohain, Alak Kumar

    2016-12-21

    Human epidermal growth factor receptor 2 (HER2) is one of the four members of the epidermal growth factor receptor (EGFR) family and is expressed to facilitate cellular proliferation across various tissue types. Therapies targeting HER2, which is a transmembrane glycoprotein with tyrosine kinase activity, offer promising prospects especially in breast and gastric/gastroesophageal cancer patients. Persistence of both primary and acquired resistance to various routine drugs/antibodies is a disappointing outcome in the treatment of many HER2 positive cancer patients and is a challenge that requires formulation of new and improved strategies to overcome the same. Identification of novel HER2 inhibitors with improved therapeutics index was performed with a highly correlating (r=0.975) ligand-based pharmacophore model (Hypo1) in this study. Hypo1 was generated from a training set of 22 compounds with HER2 inhibitory activity and this well-validated hypothesis was subsequently used as a 3D query to screen compounds in a total of four databases of which two were natural product databases. Further, these compounds were analyzed for compliance with Veber's drug-likeness rule and optimum ADMET parameters. The selected compounds were then subjected to molecular docking and Density Functional Theory (DFT) analysis to discern their molecular interactions at the active site of HER2. The findings thus presented would be an important starting point towards the development of novel HER2 inhibitors using well-validated computational techniques. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Personalizing therapies for gastric cancer: Molecular mechanisms and novel targeted therapies

    PubMed Central

    Luis, Michael; Tavares, Ana; Carvalho, Liliana S; Lara-Santos, Lúcio; Araújo, António; de Mello, Ramon Andrade

    2013-01-01

    Globally, gastric cancer is the 4th most frequently diagnosed cancer and the 2nd leading cause of death from cancer, with an estimated 990000 new cases and 738000 deaths registered in 2008. In the advanced setting, standard chemotherapies protocols acquired an important role since last decades in prolong survival. Moreover, recent advances in molecular therapies provided a new interesting weapon to treat advanced gastric cancer through anti-human epidermal growth factor receptor 2 (HER2) therapies. Trastuzumab, an anti-HER2 monoclonal antibody, was the first target drug in the metastatic setting that showed benefit in overall survival when in association with platinum-5-fluorouracil based chemotherapy. Further, HER2 overexpression analysis acquired a main role in predict response for trastuzumab in this field. Thus, we conducted a review that will discuss the main points concerning trastuzumab and HER2 in gastric cancer, providing a comprehensive overview of molecular mechanisms and novel trials involved. PMID:24151357

  10. Induction of Scleroderma Fibrosis in Skin-Humanized Mice by Administration of Anti-Platelet-Derived Growth Factor Receptor Agonistic Autoantibodies.

    PubMed

    Luchetti, Michele M; Moroncini, Gianluca; Jose Escamez, Maria; Svegliati Baroni, Silvia; Spadoni, Tatiana; Grieco, Antonella; Paolini, Chiara; Funaro, Ada; Avvedimento, Enrico V; Larcher, Fernando; Del Rio, Marcela; Gabrielli, Armando

    2016-09-01

    To describe a skin-SCID mouse chimeric model of systemic sclerosis (SSc; scleroderma) fibrosis based on engraftment of ex vivo-bioengineered skin using skin cells derived either from scleroderma patients or from healthy donors. Three-dimensional bioengineered skin containing human keratinocytes and fibroblasts isolated from skin biopsy specimens from healthy donors or SSc patients was generated ex vivo and then grafted onto the backs of SCID mice. The features of the skin grafts were analyzed by immunohistochemistry, and the functional profile of the graft fibroblasts was defined before and after treatment with IgG from healthy controls or SSc patients. Two procedures were used to investigate the involvement of platelet-derived growth factor receptor (PDGFR): 1) nilotinib, a tyrosine kinase inhibitor, was administered to mice before injection of IgG from SSc patient sera (SSc IgG) into the grafts, and 2) human anti-PDGFR monoclonal antibodies were injected into the grafts. Depending on the type of bioengineered skin grafted, the regenerated human skin exhibited either the typical scleroderma phenotype or the healthy human skin architecture. Treatment of animals carrying healthy donor skin grafts with SSc IgG resulted in the appearance of a bona fide scleroderma phenotype, as confirmed by increased collagen deposition and fibroblast activation markers. Results of the experiments involving administration of nilotinib or monoclonal antibodies confirmed the involvement of PDGFR. Our results provide the first in vivo demonstration of the fibrotic properties of anti-PDGFR agonistic antibodies. This bioengineered skin-humanized mouse model can be used to test in vivo the progression of the disease and to monitor response to antifibrotic drugs. © 2016, American College of Rheumatology.

  11. Rapid High-Level Production of Functional HIV Broadly Neutralizing Monoclonal Antibodies in Transient Plant Expression Systems

    PubMed Central

    Rosenberg, Yvonne; Sack, Markus; Montefiori, David; Forthal, Donald; Mao, Lingjun; -Abanto, Segundo Hernandez; Urban, Lori; Landucci, Gary; Fischer, Rainer; Jiang, Xiaoming

    2013-01-01

    Passive immunotherapy using anti-HIV broadly neutralizing monoclonal antibodies (mAbs) has shown promise as an HIV treatment, reducing mother-to-child-transmission (MTCT) of simian/human immunodeficiency virus (SHIV) in non-human primates and decreasing viral rebound in patients who ceased receiving anti-viral drugs. In addition, a cocktail of potent mAbs may be useful as mucosal microbicides and provide an effective therapy for post-exposure prophylaxis. However, even highly neutralizing HIV mAbs used today may lose their effectiveness if resistance occurs, requiring the rapid production of new or engineered mAbs on an ongoing basis in order to counteract the viral resistance or the spread of a certain HIV-1 clade in a particular region or patient. Plant-based expression systems are fast, inexpensive and scalable and are becoming increasingly popular for the production of proteins and monoclonal antibodies. In the present study, Agrobacterium-mediated transient transfection of plants, utilizing two species of Nicotiana, have been tested to rapidly produce high levels of an HIV 89.6PΔ140env and several well-studied anti-HIV neutralizing monoclonal antibodies (b12, 2G12, 2F5, 4E10, m43, VRC01) or a single chain antibody construct (m9), for evaluation in cell-based viral inhibition assays. The protein-A purified plant-derived antibodies were intact, efficiently bound HIV envelope, and were equivalent to, or in one case better than, their counterparts produced in mammalian CHO or HEK-293 cells in both neutralization and antibody dependent viral inhibition assays. These data indicate that transient plant-based transient expression systems are very adaptable and could rapidly generate high levels of newly identified functional recombinant HIV neutralizing antibodies when required. In addition, they warrant detailed cost-benefit analysis of prolonged incubation in plants to further increase mAb production. PMID:23533588

  12. Characterization of human monoclonal antibodies that neutralize multiple poliovirus serotypes.

    PubMed

    Puligedda, Rama Devudu; Kouiavskaia, Diana; Al-Saleem, Fetweh H; Kattala, Chandana Devi; Nabi, Usman; Yaqoob, Hamid; Bhagavathula, V Sandeep; Sharma, Rashmi; Chumakov, Konstantin; Dessain, Scott K

    2017-10-04

    Following the eradication of wild poliovirus (PV), achieving and maintaining a polio-free status will require eliminating potentially pathogenic PV strains derived from the oral attenuated vaccine. For this purpose, a combination of non-cross-resistant drugs, such as small molecules and neutralizing monoclonal antibodies (mAbs), may be ideal. We previously isolated chimpanzee and human mAbs capable of neutralizing multiple PV types (cross-neutralization). Here, we describe three additional human mAbs that neutralize types 1 and 2 PV and one mAb that neutralizes all three types. Most bind conformational epitopes and have unusually long heavy chain complementarity determining 3 domains (HC CDR3). We assessed the ability of the mAbs to neutralize A12 escape mutant PV strains, and found that the neutralizing activities of the mAbs were disrupted by different amino acid substitutions. Competitive binding studies further suggested that the specific mAb:PV interactions that enable cross-neutralization differ among mAbs and serotypes. All of the cloned mAbs bind PV in the vicinity of the "canyon", a circular depression around the 5-fold axis of symmetry through which PV recognizes its cellular receptor. We were unable to generate escape mutants to two of the mAbs, suggesting that their epitopes are important for the PV life cycle. These data indicate that PV cross-neutralization involves binding to highly conserved structures within the canyon that binds to the cellular receptor. These may be facilitated by the long HC CDR3 domains, which may adopt alternative binding configurations. We propose that the human and chimpanzee mAbs described here could have potential as anti-PV therapeutics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Novel Monoclonal Antibody LpMab-17 Developed by CasMab Technology Distinguishes Human Podoplanin from Monkey Podoplanin.

    PubMed

    Kato, Yukinari; Ogasawara, Satoshi; Oki, Hiroharu; Honma, Ryusuke; Takagi, Michiaki; Fujii, Yuki; Nakamura, Takuro; Saidoh, Noriko; Kanno, Hazuki; Umetsu, Mitsuo; Kamata, Satoshi; Kubo, Hiroshi; Yamada, Mitsuhiro; Sawa, Yoshihiko; Morita, Kei-Ichi; Harada, Hiroyuki; Suzuki, Hiroyoshi; Kaneko, Mika Kato

    2016-04-01

    Podoplanin (PDPN) is a type-I transmembrane sialoglycoprotein, which possesses a platelet aggregation-stimulating (PLAG) domain in its N-terminus. Among the three PLAG domains, O-glycan on Thr52 of PLAG3 is critical for the binding with C-type lectin-like receptor-2 (CLEC-2) and is essential for platelet-aggregating activity of PDPN. Although many anti-PDPN monoclonal antibodies (mAbs) have been established, almost all mAbs bind to PLAG domains. We recently established CasMab technology to produce mAbs against membranous proteins. Using CasMab technology, we produced a novel anti-PDPN mAb, LpMab-17, which binds to non-PLAG domains. LpMab-17 clearly detected endogenous PDPN of cancer cells and normal cells in Western-blot, flow cytometry, and immunohistochemistry. LpMab-17 recognized glycan-deficient PDPN in flow cytometry, indicating that the interaction between LpMab-17 and PDPN is independent of its glycosylation. The minimum epitope of LpMab-17 was identified as Gly77-Asp82 of PDPN using enzyme-linked immunosorbent assay. Of interest, LpMab-17 did not bind to monkey PDPN, whereas the homology is 94% between human PDPN and monkey PDPN, indicating that the epitope of LpMab-17 is unique compared with the other anti-PDPN mAbs. The combination of different epitope-possessing mAbs could be advantageous for the PDPN-targeting diagnosis or therapy.

  14. HER2/CEP17 Ratios and Clinical Outcome in HER2-Positive Early Breast Cancer Undergoing Trastuzumab-Containing Therapy.

    PubMed

    Stocker, Albina; Hilbers, Marie-Luise; Gauthier, Claire; Grogg, Josias; Kullak-Ublick, Gerd A; Seifert, Burkhardt; Varga, Zsuzsanna; Trojan, Andreas

    2016-01-01

    Adjuvant therapy comprising the HER2 receptor antagonist trastuzumab is associated with a significant improvement in disease-free and overall survival as compared to chemotherapy alone in localized HER2-positive breast cancer (BC). However, a subset of HER2-positive tumors seems to respond less favorably to trastuzumab. Various mechanisms have been proposed for trastuzumab resistance, such as high HER2 to Chromosome 17 FISH (HER2/CEP17) ratios and the possibility that single agent trastuzumab may not suffice to efficiently block HER2 downstream signaling thresholds. In a retrospective analysis we evaluated whether HER2/CEP17 ratios might have an impact on disease-free survival (DFS). Clinical records of Stage I-III BC patients with HER2-positive tumors were reviewed at our institution from 2007-2013. We analyzed demographics, tumor characteristics including tumor size and grade, lymph node involvement and estrogen receptor expression as well as treatment with respect to chemotherapeutic regimens from the clinical charts. HER2/CEP17 ratios were determined by routine pathology analysis using in situ fluorescent hybridization (FISH). Upon statistical preview we defined three groups of HER2 amplification based on FISH ratio (2.2 to 4, >4 to 8, >8), in order to evaluate an association between HER2 gene amplification and DFS with trastuzumab containing therapies. DFS was analyzed using Cox-regression. A total of 332 patients with HER2-positive BC were reviewed. Median age was 54 (range 23-89) years. The majority of tumors were classified T1 (50%) or T2 (39%), node negative (52%) and of high grade G3 histology (70%). We identified 312 (94%) tumors as immunohistochemistry (IHC) score 3+ and HER2/CEP17 ratios were available from 278 patients (84%). 30% (N = 84) had tumors with high HER2/CEP17 ratios (>8). Univariate analysis found no correlation between outcome, age, histological grade, sequence as well as anthracycline content of chemotherapy. However, a prognostic impact

  15. [Toxoplasma gondii: the characterization of an anti-P30 monoclonal antibody].

    PubMed

    Fachado, A; Fernández, N; Hernández, E; Fonseca, L

    1996-01-01

    A specific monoclonal antibody was characterized to Toxoplasma gondii. The hybridoma produced IgG immunoglobulins. The western blot analysis showed that the monoclonal antibody was specific for the antigen of an apparent molecular mass of 30 kd, which was present on the antigen surface. The monoclonal antibody was purified starting from mouse's ascitic fluid and it was matched with sepharose 4B. This immunoabsorbent was used to purify the specific parasitic antigen. The monoclonal antibody studied may be useful for those techniques contributing to the toxoplasmosis diagnosis.

  16. A molecular model for cocaine binding by the immunotherapeutic human/mouse chimeric monoclonal antibody 2E2.

    PubMed

    Lape, Michael; Paula, Stefan; Ball, William J

    2010-06-01

    Immunotherapy by cocaine-binding monoclonal antibodies (mAbs) has emerged as a promising strategy for the treatment of cocaine addiction. The human (gamma1 heavy chain)/murine (lambda light chain) chimeric mAb 2E2 has excellent affinity and specificity for cocaine and recent animal studies have demonstrated 2E2's ability in vivo to reduce cocaine levels in the brain as well as alter cocaine self-administration behavior in rats. In this study, we used mAb 2E2 amino acid sequence information to create a homology model for the 3-D structure of its Fv fragment. Subsequent computational docking studies revealed the intermolecular interactions potentially responsible for mAb 2E2's cocaine binding properties. The driving force of cocaine binding was identified as a combination of hydrophobic interactions and a single hydrogen bond between a light chain tyrosine residue and a carbonyl oxygen atom of cocaine. The model also allowed for an in silico evaluation of single/double residue mutations in the heavy and light chain variable regions that might further enhance mAb 2E2's cocaine binding properties. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

  17. A Molecular Model for Cocaine Binding by the Immunotherapeutic Human/Mouse Chimeric Monoclonal Antibody 2E2

    PubMed Central

    Lape, Michael; Paula, Stefan; Ball, William J.

    2010-01-01

    Immunotherapy by cocaine-binding monoclonal antibodies (mAbs) has emerged as a promising strategy for the treatment of cocaine addiction. The human (γ1 heavy chain)/murine (λ light chain) chimeric mAb 2E2 has excellent affinity and specificity for cocaine and recent animal studies have demonstrated 2E2’s ability in vivo to reduce cocaine levels in the brain as well as alter cocaine self-administration behavior in rats. In this study, we used mAb 2E2 amino acid sequence information to create a homology model for the 3-D structure of its Fv fragment. Subsequent computational docking studies revealed the intermolecular interactions potentially responsible for mAb 2E2’s cocaine binding properties. The driving force of cocaine binding was identified as a combination of hydrophobic interactions and a single hydrogen bond between a light chain tyrosine residue and a carbonyl oxygen atom of cocaine. The model also allowed for an in silico evaluation of single/double residue mutations in the heavy and light chain variable regions that might further enhance mAb 2E2’s cocaine binding properties. PMID:20185210

  18. Human monoclonal antibodies reactive with human myelomonocytic leukemia cells.

    PubMed

    Posner, M R; Santos, D J; Elboim, H S; Tumber, M B; Frackelton, A R

    1989-04-01

    Peripheral blood mononuclear cells from a patient with chronic myelogenous leukemia (CML), in remission, were depleted of CD8-positive T-cells and cultured with Epstein-Barr virus. Four of 20 cultures (20%) secreted human IgG antibodies selectively reactive with the cell surfaces of certain human leukemia cell lines. Three polyclonal, Epstein-Barr virus-transformed, B-cell lines were expanded and fused with the human-mouse myeloma analogue HMMA2.11TG/O. Antibody from secreting clones HL 1.2 (IgG1), HL 2.1 (IgG3), and HL 3.1 (IgG1) have been characterized. All three react with HL-60 (promyelocytic), RWLeu4 (CML promyelocytic), and U937 (monocytic), but not with KG-1 (myeloblastic) or K562 (CML erythroid). There is no reactivity with T-cell lines, Burkitt's cell lines, pre-B-leukemia cell lines, or an undifferentiated CML cell line, BV173. Leukemic cells from two of seven patients with acute myelogenous leukemia and one of five with acute lymphocytic leukemia react with all three antibodies. Normal lymphocytes, monocytes, polymorphonuclear cells, red blood cells, bone marrow cells, and platelets do not react. Samples from patients with other diverse hematopoietic malignancies showed no reactivity. Immunoprecipitations suggest that the reactive antigen(s) is a lactoperoxidase iodinatable series of cell surface proteins with molecular weights of 42,000-54,000 and a noniodinatable protein with a molecular weight of 82,000. Based on these data these human monoclonal antibodies appear to react with myelomonocytic leukemic cells and may detect a leukemia-specific antigen or a highly restricted differentiation antigen.

  19. Elucidation of the critical epitope of an anti-EGFR monoclonal antibody EMab-134.

    PubMed

    Kaneko, Mika K; Yamada, Shinji; Itai, Shunsuke; Chang, Yao-Wen; Nakamura, Takuro; Yanaka, Miyuki; Kato, Yukinari

    2018-07-01

    The epidermal growth factor receptor (EGFR) is a type-1 transmembrane receptor tyrosine kinase, which activates the downstream signaling cascades in many tumors, such as oral and lung cancers. We previously developed EMab-134, a novel anti-EGFR monoclonal antibody (mAb), which reacts with endogenous EGFR-expressing cancer cell lines and normal cells independent of glycosylation in Western blotting, flow cytometry, and immunohistochemical analysis. EMab-134 showed very high sensitivity (94.7%) to oral squamous cell carcinomas in immunohistochemical analysis. In this study, we performed enzyme-linked immunosorbent assay (ELISA), flow cytometry, and immunohistochemical analysis to determine the epitope of EMab-134. A blocking peptide (375-394 amino acids of EGFR) neutralized the EMab-134 reaction against oral cancer cells in flow cytometry and immunohistochemistry. The minimum epitope of EMab-134 was found to be the 377- RGDSFTHTPP -386 sequence. Our findings can be applied for the production of more functional anti-EGFR mAbs that in turn can be used for antitumor treatments.

  20. 4F2 monoclonal antibody recognizes a surface antigen on spread human fibroblasts of embryonic but not of adult origin

    PubMed Central

    1984-01-01

    The 4F2 monoclonal antibody (mAb) has been shown to recognize a 120- kilodalton glycoprotein expressed on the cell surface of human peripheral blood monocytes, activated (but not resting) T or B cells, and T and B lymphoblastoid cell lines. In this report we show that 4F2 mAb specifically binds to the surface of adherent human embryonic fibroblasts but fails to bind to normal adult fibroblasts. Moreover, 4F2 antigen was expressed on sarcoma-derived or SV40-transformed adult fibroblastic cells. Finally, addition of 4F2 mAb inhibited the growth of cultured HT-1080 fibrosarcoma cell line, but had no inhibitory effect on various embryonic and adult normal or transformed fibroblasts. PMID:6538202

  1. HER2 isoforms co-expression differently tunes mammary tumor phenotypes affecting onset, vasculature and therapeutic response

    PubMed Central

    Balboni, Tania; Ianzano, Marianna L.; Laranga, Roberta; Landuzzi, Lorena; Giusti, Veronica; Ceccarelli, Claudio; Santini, Donatella; Taffurelli, Mario; Di Oto, Enrico; Asioli, Sofia; Amici, Augusto; Pupa, Serenella M.; De Giovanni, Carla; Tagliabue, Elda; Iezzi, Manuela; Nanni, Patrizia; Lollini, Pier-Luigi

    2017-01-01

    Full-length HER2 oncoprotein and splice variant Delta16 are co-expressed in human breast cancer. We studied their interaction in hybrid transgenic mice bearing human full-length HER2 and Delta16 (F1 HER2/Delta16) in comparison to parental HER2 and Delta16 transgenic mice. Mammary carcinomas onset was faster in F1 HER2/Delta16 and Delta16 than in HER2 mice, however tumor growth was slower, and metastatic spread was comparable in all transgenic mice. Full-length HER2 tumors contained few large vessels or vascular lacunae, whereas Delta16 tumors presented a more regular vascularization with numerous endothelium-lined small vessels. Delta16-expressing tumors showed a higher accumulation of i.v. injected doxorubicin than tumors expressing full-length HER2. F1 HER2/Delta16 tumors with high full-length HER2 expression made few large vessels, whereas tumors with low full-length HER2 and high Delta16 contained numerous small vessels and expressed higher levels of VEGF and VEGFR2. Trastuzumab strongly inhibited tumor onset in F1 HER2/Delta16 and Delta16 mice, but not in full-length HER2 mice. Addiction of F1 tumors to Delta16 was also shown by long-term stability of Delta16 levels during serial transplants, in contrast full-length HER2 levels underwent wide fluctuations. In conclusion, full-length HER2 leads to a faster tumor growth and to an irregular vascularization, whereas Delta16 leads to a faster tumor onset, with more regular vessels, which in turn could better transport cytotoxic drugs within the tumor, and to a higher sensitivity to targeted therapeutic agents. F1 HER2/Delta16 mice are a new immunocompetent mouse model, complementary to patient-derived xenografts, for studies of mammary carcinoma onset, prevention and therapy. PMID:28903354

  2. Trastuzumab-binding peptide display by Tobacco mosaic virus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Frolova, Olga Y.; Petrunia, Igor V.; Komarova, Tatiana V.

    2010-11-10

    Human epidermal growth factor receptor-2 (HER2/neu) is a target for the humanized monoclonal antibody trastuzumab. Recently, trastuzumab-binding peptides (TBP) of HER2/neu that inhibit proliferation of breast cancer cells were identified. We have now studied conditions of efficient assembly in vivo of Tobacco mosaic virus (TMV)-based particles displaying TBP on its surface. The system is based on an Agrobacterium-mediated co-delivery of binary vectors encoding TMV RNA and coat protein (CP) with TBP in its C-terminal extension into plant leaves. We show how the fusion of amino acid substituted TBP (sTBP) to CP via a flexible peptide linker can improve the manufacturabilitymore » of recombinant TMV (rTMV). We also reveal that rTMV particles with exposed sTBP retained trastuzumab-binding capacity but lost an anti-HER2/neu immunogenic scaffold function. Mouse antibodies against rTMV did not recognize HER2/neu on surface of human SK-BR-3 cells.« less

  3. Pretargeted Radioimmunotherapy Using Anti-CD45 Monoclonal Antibodies to Deliver Radiation to Murine Hematolymphoid Tissues and Human Myeloid Leukemia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pagel, John M.; Matthews, Dana C.; Kenoyer, Aimee L.

    2009-01-01

    The efficacy of radioimmunotherapy (RIT) for treatment of patients with hematological malignancies frequently fails because of disease recurrence. We therefore conducted pretargeted RIT studies to augment the efficacy in mice of therapy using a pretargeted anti-human (h)CD45 antibody (Ab)-streptavidin (SA) conjugate followed by delivery of a biotinylated clearing agent and radiolabeled-DOTA-biotin. Tumor-to-blood ratios at 24 hours were 20:1 using pretargeted anti-hCD45 RIT and <1:1 with conventional RIT. In vivo imaging studies confirmed that the pretargeted RIT approach provided high-contrast tumor images with minimal blood-pool activity, whereas directly-labeled anti-hCD45 Ab produced distinct tumor images but the blood pool retained a largemore » amount of labeled antibody for a prolonged time. Therapy experiments demonstrated that 90Y-DOTA-biotin significantly prolonged survival of mice treated pretargeted with anti-hCD45 Ab-SA compared to mice treated with conventional RIT using 90Y-labeled anti-hCD45 Ab at the maximally tolerated dose (400 µCi). Since human CD45 antigens are confined to xenograft tumor cells in this model, and all murine tissues are devoid of hCD45 and will not bind anti-hCD45 Ab, we also compared one-step and pretargeted RIT using an anti-murine (m)CD45 Ab (A20 ) in a model where the target antigen is present on normal hematopoietic tissues. After 24 hours, 27.3 ± 2.8% of the injected dose of radionuclide was delivered per gram (% ID/g) of lymph node using 131I-A20-Ab compared with 40.0 ± 5.4% ID/g for pretargeted 111In-DOTA-biotin (p value). These data suggest that multi-step pretargeted methods for delivering RIT are superior to conventional RIT when targeting CD45 for the treatment of leukemia and may allow for the intensification of therapy, while minimizing toxicities.« less

  4. Carboplatin+Nab-paclitaxel, Plus Trastuzumab (HER2+) or Bevacizumab (HER2-) in the Neoadjuvant Setting

    ClinicalTrials.gov

    2018-01-11

    Breast Cancer; HER2-negative Breast Cancer; HER2-positive Breast Cancer; Recurrent Breast Cancer; Stage IA Breast Cancer; Stage IB Breast Cancer; Stage II Breast Cancer; Stage IIIA Breast Cancer; Stage IIIB Breast Cancer; Stage IIIC Breast Cancer

  5. HER2/CEP17 Ratios and Clinical Outcome in HER2-Positive Early Breast Cancer Undergoing Trastuzumab-Containing Therapy

    PubMed Central

    Stocker, Albina; Hilbers, Marie-Luise; Gauthier, Claire; Grogg, Josias; Kullak-Ublick, Gerd A.; Seifert, Burkhardt; Varga, Zsuzsanna

    2016-01-01

    Background Adjuvant therapy comprising the HER2 receptor antagonist trastuzumab is associated with a significant improvement in disease-free and overall survival as compared to chemotherapy alone in localized HER2-positive breast cancer (BC). However, a subset of HER2-positive tumors seems to respond less favorably to trastuzumab. Various mechanisms have been proposed for trastuzumab resistance, such as high HER2 to Chromosome 17 FISH (HER2/CEP17) ratios and the possibility that single agent trastuzumab may not suffice to efficiently block HER2 downstream signaling thresholds. In a retrospective analysis we evaluated whether HER2/CEP17 ratios might have an impact on disease-free survival (DFS). Methods Clinical records of Stage I-III BC patients with HER2-positive tumors were reviewed at our institution from 2007–2013. We analyzed demographics, tumor characteristics including tumor size and grade, lymph node involvement and estrogen receptor expression as well as treatment with respect to chemotherapeutic regimens from the clinical charts. HER2/CEP17 ratios were determined by routine pathology analysis using in situ fluorescent hybridization (FISH). Upon statistical preview we defined three groups of HER2 amplification based on FISH ratio (2.2 to 4, >4 to 8, >8), in order to evaluate an association between HER2 gene amplification and DFS with trastuzumab containing therapies. DFS was analyzed using Cox-regression. Results A total of 332 patients with HER2-positive BC were reviewed. Median age was 54 (range 23–89) years. The majority of tumors were classified T1 (50%) or T2 (39%), node negative (52%) and of high grade G3 histology (70%). We identified 312 (94%) tumors as immunohistochemistry (IHC) score 3+ and HER2/CEP17 ratios were available from 278 patients (84%). 30% (N = 84) had tumors with high HER2/CEP17 ratios (>8). Univariate analysis found no correlation between outcome, age, histological grade, sequence as well as anthracycline content of chemotherapy

  6. Local convection-enhanced delivery of an anti-CD40 agonistic monoclonal antibody induces antitumor effects in mouse glioma models.

    PubMed

    Shoji, Takuhiro; Saito, Ryuta; Chonan, Masashi; Shibahara, Ichiyo; Sato, Aya; Kanamori, Masayuki; Sonoda, Yukihiko; Kondo, Toru; Ishii, Naoto; Tominaga, Teiji

    2016-08-01

    Glioblastoma is one of the most malignant brain tumors in adults and has a dismal prognosis. In a previous report, we reported that CD40, a TNF-R-related cell surface receptor, and its ligand CD40L were associated with glioma outcomes. Here we attempted to activate CD40 signaling in the tumor and determine if it exerted therapeutic efficacy. CD40 expression was examined in 3 mouse glioma cell lines (GL261, NSCL61, and bRiTs-G3) and 5 human glioma cell lines (U87, U251, U373, T98, and A172). NSCL61 and bRiTs-G3, as glioma stem cells, also expressed the glioma stem cell markers MELK and CD44. In vitro, we demonstrated direct antitumor effects of an anti-CD40 agonistic monoclonal antibody (FGK45) against the cell lines. The efficacy of FGK45 was examined by local convection-enhanced delivery of the monoclonal antibody against each glioma model. CD40 was expressed in all mouse and human cell lines tested and was found at the cell membrane of each of the 3 mouse cell lines. FGK45 administration induced significant, direct antitumor effects in vitro. The local delivery of FGK45 significantly prolonged survival compared with controls in the NSCL61 and bRiTs-G3 models, but the effect was not significant in the GL261 model. Increases in apoptosis and CD4(+) and CD8(+) T cell infiltration were observed in the bRiTs-G3 model after FGK45 treatment. Local delivery of FGK45 significantly prolonged survival in glioma stem cell models. Thus, local delivery of this monoclonal antibody is promising for immunotherapy against gliomas. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Interlaboratory comparison of immunohistochemical testing for HER2: results of the 2004 and 2005 College of American Pathologists HER2 Immunohistochemistry Tissue Microarray Survey.

    PubMed

    Fitzgibbons, Patrick L; Murphy, Douglas A; Dorfman, David M; Roche, Patrick C; Tubbs, Raymond R

    2006-10-01

    Correct assessment of human epidermal growth factor receptor 2 (HER2) status is essential in managing patients with invasive breast carcinoma, but few data are available on the accuracy of laboratories performing HER2 testing by immunohistochemistry (IHC). To review the results of the 2004 and 2005 College of American Pathologists HER2 Immunohistochemistry Tissue Microarray Survey. The HER2 survey is designed for laboratories performing immunohistochemical staining and interpretation for HER2. The survey uses tissue microarrays, each consisting of ten 3-mm tissue cores obtained from different invasive breast carcinomas. All cases are also analyzed by fluorescence in situ hybridization. Participants receive 8 tissue microarrays (80 cases) with instructions to perform immunostaining for HER2 using the laboratory's standard procedures. The laboratory interprets the stained slides and returns results to the College of American Pathologists for analysis. In 2004 and 2005, a core was considered "graded" when at least 90% of laboratories agreed on the result--negative (0, 1+) versus positive (2+, 3+). This interlaboratory comparison survey included 102 laboratories in 2004 and 141 laboratories in 2005. Of the 160 cases in both surveys, 111 (69%) achieved 90% consensus (graded). All 43 graded cores scored as IHC-positive were fluorescence in situ hybridization-positive, whereas all but 3 of the 68 IHC-negative graded cores were fluorescence in situ hybridization-negative. Ninety-seven (95%) of 102 laboratories in 2004 and 129 (91%) of 141 laboratories in 2005 correctly scored at least 90% of the graded cores. Performance among laboratories performing HER2 IHC in this tissue microarray-based survey was excellent. Cores found to be IHC-positive or IHC-negative by participant consensus can be used as validated benchmarks for interlaboratory comparison, allowing laboratories to assess their performance and determine if improvements are needed.

  8. Neratinib Efficacy and Circulating Tumor DNA Detection of HER2 Mutations in HER2 Nonamplified Metastatic Breast Cancer.

    PubMed

    Ma, Cynthia X; Bose, Ron; Gao, Feng; Freedman, Rachel A; Telli, Melinda L; Kimmick, Gretchen; Winer, Eric; Naughton, Michael; Goetz, Matthew P; Russell, Christy; Tripathy, Debu; Cobleigh, Melody; Forero, Andres; Pluard, Timothy J; Anders, Carey; Niravath, Polly Ann; Thomas, Shana; Anderson, Jill; Bumb, Caroline; Banks, Kimberly C; Lanman, Richard B; Bryce, Richard; Lalani, Alshad S; Pfeifer, John; Hayes, Daniel F; Pegram, Mark; Blackwell, Kimberly; Bedard, Philippe L; Al-Kateb, Hussam; Ellis, Matthew J C

    2017-10-01

    Purpose: Based on promising preclinical data, we conducted a single-arm phase II trial to assess the clinical benefit rate (CBR) of neratinib, defined as complete/partial response (CR/PR) or stable disease (SD) ≥24 weeks, in HER2 mut nonamplified metastatic breast cancer (MBC). Secondary endpoints included progression-free survival (PFS), toxicity, and circulating tumor DNA (ctDNA) HER2 mut detection. Experimental Design: Tumor tissue positive for HER2 mut was required for eligibility. Neratinib was administered 240 mg daily with prophylactic loperamide. ctDNA sequencing was performed retrospectively for 54 patients (14 positive and 40 negative for tumor HER2 mut ). Results: Nine of 381 tumors (2.4%) sequenced centrally harbored HER2 mut (lobular 7.8% vs. ductal 1.6%; P = 0.026). Thirteen additional HER2 mut cases were identified locally. Twenty-one of these 22 HER2 mut cases were estrogen receptor positive. Sixteen patients [median age 58 (31-74) years and three (2-10) prior metastatic regimens] received neratinib. The CBR was 31% [90% confidence interval (CI), 13%-55%], including one CR, one PR, and three SD ≥24 weeks. Median PFS was 16 (90% CI, 8-31) weeks. Diarrhea (grade 2, 44%; grade 3, 25%) was the most common adverse event. Baseline ctDNA sequencing identified the same HER2 mut in 11 of 14 tumor-positive cases (sensitivity, 79%; 90% CI, 53%-94%) and correctly assigned 32 of 32 informative negative cases (specificity, 100%; 90% CI, 91%-100%). In addition, ctDNA HER2 mut variant allele frequency decreased in nine of 11 paired samples at week 4, followed by an increase upon progression. Conclusions: Neratinib is active in HER2 mut , nonamplified MBC. ctDNA sequencing offers a noninvasive strategy to identify patients with HER2 mut cancers for clinical trial participation. Clin Cancer Res; 23(19); 5687-95. ©2017 AACR . ©2017 American Association for Cancer Research.

  9. Relevance of deep learning to facilitate the diagnosis of HER2 status in breast cancer

    NASA Astrophysics Data System (ADS)

    Vandenberghe, Michel E.; Scott, Marietta L. J.; Scorer, Paul W.; Söderberg, Magnus; Balcerzak, Denis; Barker, Craig

    2017-04-01

    Tissue biomarker scoring by pathologists is central to defining the appropriate therapy for patients with cancer. Yet, inter-pathologist variability in the interpretation of ambiguous cases can affect diagnostic accuracy. Modern artificial intelligence methods such as deep learning have the potential to supplement pathologist expertise to ensure constant diagnostic accuracy. We developed a computational approach based on deep learning that automatically scores HER2, a biomarker that defines patient eligibility for anti-HER2 targeted therapies in breast cancer. In a cohort of 71 breast tumour resection samples, automated scoring showed a concordance of 83% with a pathologist. The twelve discordant cases were then independently reviewed, leading to a modification of diagnosis from initial pathologist assessment for eight cases. Diagnostic discordance was found to be largely caused by perceptual differences in assessing HER2 expression due to high HER2 staining heterogeneity. This study provides evidence that deep learning aided diagnosis can facilitate clinical decision making in breast cancer by identifying cases at high risk of misdiagnosis.

  10. Production and characterization of monoclonal antibodies (mAbs) against human serum albumin (HSA) for the development of an immunoaffinity system with oriented anti-HSA mAbs as immobilized ligand.

    PubMed

    Rajak, Poonam; Vijayalakshmi, M A; Jayaprakash, N S

    2013-05-05

    Proteins present in human serum are of immense importance in the field of biomarker discovery. But, the presence of high-abundant proteins like albumin makes the analysis more challenging because of masking effect on low-abundant proteins. Therefore, removal of albumin using highly specific monoclonal antibodies (mAbs) can potentiate the discovery of low-abundant proteins. In the present study, mAbs against human serum albumin (HSA) were developed and integrated in to an immunoaffinity based system for specific removal of albumin from the serum. Hybridomas were obtained by fusion of Sp2/0 mouse myeloma cells with spleen cells from the mouse immunized with HSA. Five clones (AHSA1-5) producing mAbs specific to HSA were established and characterized by enzyme linked immunosorbent assay (ELISA) and immunoblotting for specificity, sensitivity and affinity in terms of antigen binding. The mAbs were able to bind to both native albumin as well as its glycated isoform. Reactivity of mAbs with different mammalian sera was tested. The affinity constant of the mAbs ranged from 10(8) to 10(9)M(-1). An approach based on oriented immobilization was followed to immobilize purified anti-HSA mAbs on hydrazine activated agarose gel and the dynamic binding capacity of the column was determined. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Development of 64Cu-NOTA-Trastuzumab for HER2 targeting: radiopharmaceutical with improved pharmacokinetics for human study.

    PubMed

    Woo, Sang-Keun; Jang, Su Jin; Seo, Min-Jung; Park, Ju Hui; Kim, Byoung Soo; Kim, Eun Jung; Lee, Yong Jin; Lee, Tae Sup; An, Gwang Il; Song, In Ho; Seo, Youngho; Kim, Kwang Il; Kang, Joo Hyun

    2018-05-18

    Purpose The purpose of this study was to develop 64 Cu-labeled trastuzumab with improved pharmacokinetics for human epidermal growth factor receptor 2. Methods Trastuzumab was conjugated with SCN-Bn-NOTA and radiolabeled with 64 Cu. Serum stability and immunoreactivity of 64 Cu-NOTA-trastuzumab were tested. Small animal PET imaging and biodistribution study were performed in HER2-positive breast cancer xenograft model (BT-474). Internal dosimetry of experimental animals was performed using the image-based approach with the Monte Carlo N-Particle Code. Results 64 Cu-NOTA-trastuzumab was prepared with high radiolabel yield and radiochemical purity (>98%) and showed high stability in serum and good immunoreactivity. Uptake of 64 Cu-NOTA-trastuzumab was highest at 48 h after injection determined by PET imaging and biodistribution results in BT-474 tumors. The blood radioactivity concentrations of 64 Cu-NOTA-trastuzumab decreased bi-exponentially with time in both mice with and without BT-474 tumor xenografts. The calculated absorbed dose of 64 Cu-NOTA-trastuzumab was 0.048 mGy/MBq for the heart, 0.079 for the liver and 0.047 for the spleen. Conclusion 64 Cu-NOTA-trastuzumab was effectively targeted to the HER2-expressing tumor in vitro and in vivo , and it exhibited relatively low absorbed dose due to short residence time. Therefore, 64 Cu-NOTA-trastuzumab could be applied to select the right patients/right timing for HER2 therapy, to monitor the treatment response after HER2-targeted therapy, and to detect distal or metastatic spread. Copyright © 2018 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  12. Passive vaccination with a human monoclonal antibody: generation of antibodies and studies for efficacy in Bacillus anthracis infections.

    PubMed

    vor dem Esche, Ulrich; Huber, Maria; Zgaga-Griesz, Andrea; Grunow, Roland; Beyer, Wolfgang; Hahn, Ulrike; Bessler, Wolfgang G

    2011-07-01

    A major difficulty in creating human monoclonal antibodies is the lack of a suitable myeloma cell line to be used for fusion experiments. In order to create fully human monoclonal antibodies for passive immunization, the human mouse heteromyeloma cell line CB-F7 was evaluated. Using this cell line, we generated human monoclonal antibodies against Bacillus anthracis toxin components. Antibodies against protective antigen (PA) and against lethal factor (LF) were obtained using peripheral blood lymphocytes (PBLs) from persons vaccinated with the UK anthrax vaccine. PBL were fused with the cell line CB-F7. We obtained several clones producing PA specific Ig and one clone (hLF1-SAN) producing a monoclonal antibody (hLF1) directed against LF. The LF binding antibody was able to neutralize Anthrax toxin activity in an in vitro neutralization assay, and preliminary in vivo studies in mice also indicated a trend towards protection. We mapped the epitope of the antibody binding to LF by dot blot analysis and ELIFA using 80 synthetic LF peptides of 20 amino acid lengths with an overlapping range of 10 amino acids. Our results suggest the binding of the monoclonal antibody to the peptide regions 121-150 or 451-470 of LF. The Fab-fragment of the antibody hLF1 was cloned in Escherichia coli and could be useful as part of a fully human monoclonal antibody for the treatment of Anthrax infections. In general, our studies show the applicability of the CB-F7 line to create fully human monoclonal antibodies for vaccination. Copyright © 2010 Elsevier GmbH. All rights reserved.

  13. Steroid receptor coactivators, HER-2 and HER-3 expression is stimulated by tamoxifen treatment in DMBA-induced breast cancer.

    PubMed

    Moi, Line L Haugan; Flågeng, Marianne Hauglid; Gjerde, Jennifer; Madsen, Andre; Røst, Therese Halvorsen; Gudbrandsen, Oddrun Anita; Lien, Ernst A; Mellgren, Gunnar

    2012-06-15

    Steroid receptor coactivators (SRCs) may modulate estrogen receptor (ER) activity and the response to endocrine treatment in breast cancer, in part through interaction with growth factor receptor signaling pathways. In the present study the effects of tamoxifen treatment on the expression of SRCs and human epidermal growth factor receptors (HERs) were examined in an animal model of ER positive breast cancer. Sprague-Dawley rats with DMBA-induced breast cancer were randomized to 14 days of oral tamoxifen 40 mg/kg bodyweight/day or vehicle only (controls). Tumors were measured throughout the study period. Blood samples and tumor tissue were collected at sacrifice and tamoxifen and its main metabolites were quantified using LC-MS/MS. The gene expression in tumor of SRC-1, SRC-2/transcription intermediary factor-2 (TIF-2), SRC-3/amplified in breast cancer 1 (AIB1), ER, HER-1, -2, -3 and HER-4, as well as the transcription factor Ets-2, was measured by real-time RT-PCR. Protein levels were further assessed by Western blotting. Tamoxifen and its main metabolites were detected at high concentrations in serum and accumulated in tumor tissue in up to tenfolds the concentration in serum. Mean tumor volume/rat decreased in the tamoxifen treated group, but continued to increase in controls. The mRNA expression levels of SRC-1 (P = 0.035), SRC-2/TIF-2 (P = 0.002), HER-2 (P = 0.035) and HER-3 (P = 0.006) were significantly higher in tamoxifen treated tumors compared to controls, and the results were confirmed at the protein level using Western blotting. SRC-3/AIB1 protein was also higher in tamoxifen treated tumors. SRC-1 and SRC-2/TIF-2 mRNA levels were positively correlated with each other and with HER-2 (P ≤ 0.001), and the HER-2 mRNA expression correlated with the levels of the other three HER family members (P < 0.05). Furthermore, SRC-3/AIB1 and HER-4 were positively correlated with each other and Ets-2 (P < 0.001). The expression of SRCs

  14. Steroid receptor coactivators, HER-2 and HER-3 expression is stimulated by tamoxifen treatment in DMBA-induced breast cancer

    PubMed Central

    2012-01-01

    Background Steroid receptor coactivators (SRCs) may modulate estrogen receptor (ER) activity and the response to endocrine treatment in breast cancer, in part through interaction with growth factor receptor signaling pathways. In the present study the effects of tamoxifen treatment on the expression of SRCs and human epidermal growth factor receptors (HERs) were examined in an animal model of ER positive breast cancer. Methods Sprague-Dawley rats with DMBA-induced breast cancer were randomized to 14 days of oral tamoxifen 40 mg/kg bodyweight/day or vehicle only (controls). Tumors were measured throughout the study period. Blood samples and tumor tissue were collected at sacrifice and tamoxifen and its main metabolites were quantified using LC-MS/MS. The gene expression in tumor of SRC-1, SRC-2/transcription intermediary factor-2 (TIF-2), SRC-3/amplified in breast cancer 1 (AIB1), ER, HER-1, -2, -3 and HER-4, as well as the transcription factor Ets-2, was measured by real-time RT-PCR. Protein levels were further assessed by Western blotting. Results Tamoxifen and its main metabolites were detected at high concentrations in serum and accumulated in tumor tissue in up to tenfolds the concentration in serum. Mean tumor volume/rat decreased in the tamoxifen treated group, but continued to increase in controls. The mRNA expression levels of SRC-1 (P = 0.035), SRC-2/TIF-2 (P = 0.002), HER-2 (P = 0.035) and HER-3 (P = 0.006) were significantly higher in tamoxifen treated tumors compared to controls, and the results were confirmed at the protein level using Western blotting. SRC-3/AIB1 protein was also higher in tamoxifen treated tumors. SRC-1 and SRC-2/TIF-2 mRNA levels were positively correlated with each other and with HER-2 (P ≤ 0.001), and the HER-2 mRNA expression correlated with the levels of the other three HER family members (P < 0.05). Furthermore, SRC-3/AIB1 and HER-4 were positively correlated with each other and Ets-2 (P < 0

  15. Therapeutic monoclonal antibodies in human breast milk: a case study.

    PubMed

    Ross, Elle; Robinson, Steven E; Amato, Carol; McMillan, Colette; Westcott, Jay; Wolf, Tiffany; Robinson, William A

    2014-04-01

    Recently, therapeutic monoclonal antibodies have been introduced for the treatment of advanced melanoma and other diseases. It remains unclear whether these drugs can be safely administered to women who are breast feeding because of the potential hazardous side effects for nursing infants. One such therapy for metastatic melanoma is ipilimumab, a human monoclonal antibody that blocks cytotoxic T-lymphocyte-antigen-4, and is the preferred treatment for patients with metastatic melanoma when other molecular therapies are not viable. This study measured ipilimumab levels in the breast milk of a patient undergoing treatment that were enough to raise concerns for a nursing infant exposed to ipilimumab.

  16. Monoclonal Antibody L1Mab-13 Detected Human PD-L1 in Lung Cancers.

    PubMed

    Yamada, Shinji; Itai, Shunsuke; Nakamura, Takuro; Yanaka, Miyuki; Chang, Yao-Wen; Suzuki, Hiroyoshi; Kaneko, Mika K; Kato, Yukinari

    2018-04-01

    Programmed cell death ligand-1 (PD-L1) is a type I transmembrane glycoprotein expressed on antigen-presenting cells. It is also expressed in several tumor cells such as melanoma and lung cancer cells. A strong correlation has been reported between human PD-L1 (hPD-L1) expression in tumor cells and negative prognosis in cancer patients. Here, a novel anti-hPD-L1 monoclonal antibody (mAb) L 1 Mab-13 (IgG 1 , kappa) was produced using a cell-based immunization and screening (CBIS) method. We investigated hPD-L1 expression in lung cancer using flow cytometry, Western blot, and immunohistochemical analyses. L 1 Mab-13 specifically reacted hPD-L1 of hPD-L1-overexpressed Chinese hamster ovary (CHO)-K1 cells and endogenous hPD-L1 of KMST-6 (human fibroblast) in flow cytometry and Western blot. Furthermore, L 1 Mab-13 reacted with lung cancer cell lines (EBC-1, Lu65, and Lu99) in flow cytometry and stained lung cancer tissues in a membrane-staining pattern in immunohistochemical analysis. These results indicate that a novel anti-hPD-L1 mAb, L 1 Mab-13, is very useful for detecting hPD-L1 of lung cancers in flow cytometry, Western blot, and immunohistochemical analyses.

  17. Evaluation of human epidermal growth factor receptor 2 (HER2) single nucleotide polymorphisms (SNPs) in normal and breast tumor tissues and their link with breast cancer prognostic factors.

    PubMed

    Furrer, Daniela; Lemieux, Julie; Côté, Marc-André; Provencher, Louise; Laflamme, Christian; Barabé, Frédéric; Jacob, Simon; Michaud, Annick; Diorio, Caroline

    2016-12-01

    Amplification of the human epidermal growth factor receptor 2 (HER2) gene is associated with worse prognosis and decreased overall survival in breast cancer patients. The HER2 gene contains several polymorphisms; two of the best-characterized HER2 polymorphisms are Ile655Val and Ala1170Pro. The aim of this study was to evaluate the association between these two HER2 polymorphisms in normal breast and breast cancer tissues and known breast cancer prognostic factors in a retrospective cohort study of 73 women with non-metastatic HER2-positive breast cancer. HER2 polymorphisms were assessed in breast cancer tissue and normal breast tissue using TaqMan assay. Ala1170Pro polymorphism in normal breast tissue was associated with age at diagnosis (p = 0.007), tumor size (p = 0.004) and lymphovascular invasion (p = 0.06). Similar significant associations in cancer tissues were observed. No association between the Ile655Val polymorphism and prognostic factors were observed. However, we found significant differences in the distribution of Ile655Val (p = 0.03) and Ala1170Pro (p = 0.01) genotypes between normal breast and breast tumor tissues. This study demonstrates that only the Ala1170Pro polymorphism is associated with prognostic factors in HER2-positive breast cancer patients. Moreover, our results suggest that both HER2 polymorphisms could play a significant role in carcinogenesis in non-metastatic HER2-positive breast cancer women. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Resistance to therapy in estrogen receptor positive and human epidermal growth factor 2 positive breast cancers: progress with latest therapeutic strategies.

    PubMed

    Lousberg, Laurence; Collignon, Joëlle; Jerusalem, Guy

    2016-11-01

    In this article, we focus on the subtype of estrogen receptor (ER)-positive, human epidermal growth factor 2 (HER2)-positive breast cancer (BC). Preclinical and clinical data indicate a complex molecular bidirectional crosstalk between the ER and HER2 pathways. This crosstalk probably constitutes one of the key mechanisms of drug resistance in this subclass of BC. Delaying or even reversing drug resistance seems possible by targeting pathways implicated in this crosstalk. High-risk patients currently receive anti-HER2 therapy, chemotherapy and endocrine therapy in the adjuvant setting. In metastatic cases, most patients receive a combination of anti-HER2 therapy and chemotherapy. Only selected patients presenting more indolent disease are candidates for combinations of anti-HER2 therapy and endocrine therapy. However, relative improvements in progression-free survival by chemotherapy-based regimens are usually lower in ER-positive patients than the ER-negative and HER2-positive subgroup. Consequently, new approaches aiming to overcome endocrine therapy resistance by adding targeted therapies to endocrine therapy based regimens are currently explored. In addition, dual blockade of HER2 or the combination of trastuzumab and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOP) inhibitors targeting the downstream pathway are strategies to overcome resistance to trastuzumab. This may lead in the near future to the less frequent use of chemotherapy-based treatment options in ER-positive, HER2-positive BC.

  19. Role of cannabinoid receptor CB2 in HER2 pro-oncogenic signaling in breast cancer.

    PubMed

    Pérez-Gómez, Eduardo; Andradas, Clara; Blasco-Benito, Sandra; Caffarel, María M; García-Taboada, Elena; Villa-Morales, María; Moreno, Estefanía; Hamann, Sigrid; Martín-Villar, Ester; Flores, Juana M; Wenners, Antonia; Alkatout, Ibrahim; Klapper, Wolfram; Röcken, Christoph; Bronsert, Peter; Stickeler, Elmar; Staebler, Annette; Bauer, Maret; Arnold, Norbert; Soriano, Joaquim; Pérez-Martínez, Manuel; Megías, Diego; Moreno-Bueno, Gema; Ortega-Gutiérrez, Silvia; Artola, Marta; Vázquez-Villa, Henar; Quintanilla, Miguel; Fernández-Piqueras, José; Canela, Enric I; McCormick, Peter J; Guzmán, Manuel; Sánchez, Cristina

    2015-06-01

    Pharmacological activation of cannabinoid receptors elicits antitumoral responses in different cancer models. However, the biological role of these receptors in tumor physio-pathology is still unknown. We analyzed CB2 cannabinoid receptor protein expression in two series of 166 and 483 breast tumor samples operated in the University Hospitals of Kiel, Tübingen, and Freiburg between 1997 and 2010 and CB2 mRNA expression in previously published DNA microarray datasets. The role of CB2 in oncogenesis was studied by generating a mouse line that expresses the human V-Erb-B2 Avian Erythroblastic Leukemia Viral Oncogene Homolog 2 (HER2) rat ortholog (neu) and lacks CB2 and by a variety of biochemical and cell biology approaches in human breast cancer cells in culture and in vivo, upon modulation of CB2 expression by si/shRNAs and overexpression plasmids. CB2-HER2 molecular interaction was studied by colocalization, coimmunoprecipitation, and proximity ligation assays. Statistical tests were two-sided. We show an association between elevated CB2 expression in HER2+ breast tumors and poor patient prognosis (decreased overall survival, hazard ratio [HR] = 0.29, 95% confidence interval [CI] = 0.09 to 0.71, P = .009) and higher probability to suffer local recurrence (HR = 0.09, 95% CI = 0.049 to 0.54, P = .003) and to develop distant metastases (HR = 0.33, 95% CI = 0.13 to 0.75, P = .009). We also demonstrate that genetic inactivation of CB2 impairs tumor generation and progression in MMTV-neu mice. Moreover, we show that HER2 upregulates CB2 expression by activating the transcription factor ELK1 via the ERK cascade and that an increased CB2 expression activates the HER2 pro-oncogenic signaling at the level of the tyrosine kinase c-SRC. Finally, we show HER2 and CB2 form heteromers in cancer cells. Our findings reveal an unprecedented role of CB2 as a pivotal regulator of HER2 pro-oncogenic signaling in breast cancer, and they suggest that CB2 may be a biomarker with

  20. Design, biological evaluation and 3D QSAR studies of novel dioxin-containing pyrazoline derivatives with thiourea skeleton as selective HER-2 inhibitors

    NASA Astrophysics Data System (ADS)

    Yang, Bing; Yang, Yu-Shun; Yang, Na; Li, Guigen; Zhu, Hai-Liang

    2016-06-01

    A series of novel dioxin-containing pyrazoline derivatives with thiourea skeleton have been designed, synthesized and evaluated for their EGFR/HER-2 inhibitory and anti-proliferation activities. A majority of them displayed selective HER-2 inhibitory activity against EGFR inhibitory activity. Compound C20 displayed the most potent activity against HER-2 and MDA-MB-453 human breast cancer cell line (IC50 = 0.03 μM and GI50 = 0.15 μM), being slightly more potent than the positive control Erlotinib (IC50 = 0.16 μM and GI50 = 1.56 μM) and comparable with Lapatinib (IC50 = 0.01 μM and GI50 = 0.03 μM). It is a more exciting result that C20 was over 900 times more potent against HER-2 than against EGFR while this value was 0.19 for Erlotinib and 1.00 for Lapatinib, indicating high selectivity. The results of docking simulation indicate that the dioxin moiety occupied the exit of the active pocket and pushed the carbothioamide deep into the active site. QSAR models have been built with activity data and binding conformations to begin our work in this paper as well as to provide a reliable tool for reasonable design of EGFR/HER-2 inhibitors in future.

  1. HER2-specific T cells target primary glioblastoma stem cells and induce regression of autologous experimental tumors.

    PubMed

    Ahmed, Nabil; Salsman, Vita S; Kew, Yvonne; Shaffer, Donald; Powell, Suzanne; Zhang, Yi J; Grossman, Robert G; Heslop, Helen E; Gottschalk, Stephen

    2010-01-15

    Glioblastoma multiforme (GBM) is the most aggressive human primary brain tumor and is currently incurable. Immunotherapies have the potential to target GBM stem cells, which are resistant to conventional therapies. Human epidermal growth factor receptor 2 (HER2) is a validated immunotherapy target, and we determined if HER2-specific T cells can be generated from GBM patients that will target autologous HER2-positive GBMs and their CD133-positive stem cell compartment. HER2-specific T cells from 10 consecutive GBM patients were generated by transduction with a retroviral vector encoding a HER2-specific chimeric antigen receptor. The effector function of HER2-specific T cells against autologous GBM cells, including CD133-positive stem cells, was evaluated in vitro and in an orthotopic murine xenograft model. Stimulation of HER2-specific T cells with HER2-positive autologous GBM cells resulted in T-cell proliferation and secretion of IFN-gamma and interleukin-2 in a HER2-dependent manner. Patients' HER2-specific T cells killed CD133-positive and CD133-negative cells derived from primary HER2-positive GBMs, whereas HER2-negative tumor cells were not killed. Injection of HER2-specific T cells induced sustained regression of autologous GBM xenografts established in the brain of severe combined immunodeficient mice. Gene transfer allows the reliable generation of HER2-specific T cells from GBM patients, which have potent antitumor activity against autologous HER2-positive tumors including their putative stem cells. Hence, the adoptive transfer of HER2-redirected T cells may be a promising immunotherapeutic approach for GBM.

  2. Rapid and ultrasensitive flexible palladium nano-thin film biosensing electrode development for cancer antigen HER2 detection

    NASA Astrophysics Data System (ADS)

    Huang, Yun-Tzu; Chang, Chia-Yu; Chen, Wei; Su, Chien-Hao; Hsu, Guo-Cheng; Chang, Chia-Ching

    HER2 (human epidermal growth factor receptor 2) is one of the significant surface antigens of breast cancer Trace amount of HER2 protein in human serum is highly correlated to the tumor progression in breast cancers especially in the cases of recurrence. Therefore, HER2 detection of human serum is significant for early detection of cancer recurrence. Conventional HER2 detection approaches may not be sensitive enough or contain highly false positive rate or time consuming for accurate detection. Therefore, a rapid, highly sensitive and specific sensing is highly desired. By using HER2 specific binding peptide functionalized palladium thin film electrochemical electrode the HER2 protein concentration can be determined at sub-nanogram level by electrochemical impedance spectroscopy (EIS) within 10 mins. The Pd nano-film is sputtered on the flexible plastics substrate and reduces the cost of this electrode. Due to the low cost of the electrode, it is designed as a disposable biosensing probe which may reduce the concern of human sample contamination. The self-management after breast cancer operation may be feasible in the near future. Keywords: Electrochemical impedance spectroscopy(EIS), breast cancer, biosensor Corresponding author: ccchang01@faculty.nctu.edu.tw; Cheeshin Technology Co. Collaboration.

  3. Immunohistochemistry and alternative FISH testing in breast cancer with HER2 equivocal amplification.

    PubMed

    Agersborg, Sally; Mixon, Christopher; Nguyen, Thanh; Aithal, Sramila; Sudarsanam, Sucha; Blocker, Forrest; Weiss, Lawrence; Gasparini, Robert; Jiang, Shiping; Chen, Wayne; Hess, Gregory; Albitar, Maher

    2018-03-22

    While HER2 testing is well established in directing appropriate treatment for breast cancer, a small percentage of cases show equivocal results by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Alternative probes may be used in equivocal cases. We present a single community-based institution's experience in further evaluating these cases. Between 2014 and 2016, 4255 samples were submitted for HER2 amplification testing by alternative probes, TP53, RAI1, and RARA. Of the patients tested by FISH, 505/3908 (12.9%) also had IHC data. Most (73.9%) FISH equivocal cases remained equivocal after IHC testing. However, 50.5% of equivocal cases were classified as HER2 amplified by alternative probes. Most cases were positive by more than one probe: 78% of positive cases by RAI1 and 73.9% by TP53. There was a significant difference between IHC and FISH alternative testing (p < 0.0001) among the equivocal cases by conventional FISH testing, 44% of IHC negative cases became positive while 36% of the positive IHC cases became negative by alternative FISH testing. Available data showed that 41% of patients were treated with palbociclib and were positive by alternative FISH. The prevalence of double HER2 equivocal cases and the discrepancy between IHC and alternative FISH testing suggest that FISH alternative testing using both RAI1 and TP53 probes is necessary for conclusive classification. Because almost half of FISH equivocal cases converted to HER2 amplified upon alternative testing, clinical studies to determine the benefit of anti-HER2 therapy in these patients are urgently needed.

  4. Molecular and Therapeutic Characterization of Anti-ectodysplasin A Receptor (EDAR) Agonist Monoclonal Antibodies*

    PubMed Central

    Kowalczyk, Christine; Dunkel, Nathalie; Willen, Laure; Casal, Margret L.; Mauldin, Elizabeth A.; Gaide, Olivier; Tardivel, Aubry; Badic, Giovanna; Etter, Anne-Lise; Favre, Manuel; Jefferson, Douglas M.; Headon, Denis J.; Demotz, Stéphane; Schneider, Pascal

    2011-01-01

    The TNF family ligand ectodysplasin A (EDA) and its receptor EDAR are required for proper development of skin appendages such as hair, teeth, and eccrine sweat glands. Loss of function mutations in the Eda gene cause X-linked hypohidrotic ectodermal dysplasia (XLHED), a condition that can be ameliorated in mice and dogs by timely administration of recombinant EDA. In this study, several agonist anti-EDAR monoclonal antibodies were generated that cross-react with the extracellular domains of human, dog, rat, mouse, and chicken EDAR. Their half-life in adult mice was about 11 days. They induced tail hair and sweat gland formation when administered to newborn EDA-deficient Tabby mice, with an EC50 of 0.1 to 0.7 mg/kg. Divalency was necessary and sufficient for this therapeutic activity. Only some antibodies were also agonists in an in vitro surrogate activity assay based on the activation of the apoptotic Fas pathway. Activity in this assay correlated with small dissociation constants. When administered in utero in mice or at birth in dogs, agonist antibodies reverted several ectodermal dysplasia features, including tooth morphology. These antibodies are therefore predicted to efficiently trigger EDAR signaling in many vertebrate species and will be particularly suited for long term treatments. PMID:21730053

  5. Allotype suppression in an adoptive transfer system in adult mice: the specificity and feedback effects of a monoclonal IgG3 anti-(Igh-1b) allotype antibody.

    PubMed Central

    Curling, E M; Dresser, D W

    1984-01-01

    Using an adoptive transfer system in mice, an allotype-specific suppression has been induced by a monoclonal IgG3 anti-Igh-1b (Hyb 5.7) reagent. Suppression was specific for IgG2a (Igh-1b) and led to a compensatory increase of the Igh-1a response in irradiated mice reconstituted with allotype heterozygous (Igha/b) spleen cells. Suppression, which was not antigen-specific, lasted for at least 1 month after anti-allotype treatment. PMID:6365744

  6. Binding Affinity, Specificity and Comparative Biodistribution of the Parental Murine Monoclonal Antibody MX35 (Anti-NaPi2b) and Its Humanized Version Rebmab200.

    PubMed

    Lindegren, Sture; Andrade, Luciana N S; Bäck, Tom; Machado, Camila Maria L; Horta, Bruno Brasil; Buchpiguel, Carlos; Moro, Ana Maria; Okamoto, Oswaldo Keith; Jacobsson, Lars; Cederkrantz, Elin; Washiyama, Kohshin; Aneheim, Emma; Palm, Stig; Jensen, Holger; Tuma, Maria Carolina B; Chammas, Roger; Hultborn, Ragnar; Albertsson, Per

    2015-01-01

    The aim of this preclinical study was to evaluate the characteristics of the monoclonal antibody Rebmab200, which is a humanized version of the ovarian-specific murine antibody MX35. This investigation contributes to the foundation for future clinical α-radioimmunotherapy of minimal residual ovarian cancer with 211At-Rebmab200. Here, the biodistribution of 211At-Rebmab200 was evaluated, as was the utility of 99mTc-Rebmab200 for bioimaging. Rebmab200 was directly compared with its murine counterpart MX35 in terms of its in-vitro capacity for binding the immobilized NaPi2B epitope and live cells; we also assessed its biodistribution in nude mice carrying subcutaneous OVCAR-3 tumors. Tumor antigen and cell binding were similar between Rebmab200 and murine MX35, as was biodistribution, including normal tissue uptake and in-vivo tumor binding. We also demonstrated that 99mTc-Rebmab200 can be used for single-photon emission computed tomography of subcutaneous ovarian carcinomas in tumor-bearing mice. Taken together, our data support the further development of Rebmab200 for radioimmunotherapy and diagnostics.

  7. Production and characterization of monoclonal antibodies against cathepsin B and cathepsin B-Like proteins of Naegleria fowleri.

    PubMed

    Seong, Gi-Sang; Sohn, Hae-Jin; Kang, Heekyoung; Seo, Ga-Eun; Kim, Jong-Hyun; Shin, Ho-Joon

    2017-12-01

    Naegleria fowleri causes fatal primary amoebic meningoencephalitis (PAM) in humans and experimental animals. In previous studies, cathepsin B (nfcpb) and cathepsin B-like (nfcpb-L) genes of N. fowleri were cloned, and it was suggested that refolding rNfCPB and rNfCPB-L proteins could play important roles in host tissue invasion, immune response evasion and nutrient uptake. In this study, we produced anti-NfCPB and anti-NfCPB-L monoclonal antibodies (McAb) using a cell fusion technique, and observed their immunological characteristics. Seven hybridoma cells secreting rNfCPB McAbs and three hybridoma cells secreting rNfCPB-L McAbs were produced. Among these, 2C9 (monoclone for rNfCPB) and 1C8 (monoclone for rNfCPB-L) McAb showed high antibody titres and were finally selected for use. As determined by western blotting, 2C9 McAb bound to N. fowleri lysates, specifically the rNfCPB protein, which had bands of 28 kDa and 38.4 kDa. 1C8 McAb reacted with N. fowleri lysates, specifically the rNfCPB-L protein, which had bands of 24 kDa and 34 kDa. 2C9 and 1C8 monoclonal antibodies did not bind to lysates of other amoebae, such as N. gruberi, Acanthamoeba castellanii and A. polyphaga in western blot analyses. Immuno-cytochemistry analysis detected NfCPB and NfCPB-L proteins in the cytoplasm of N. fowleri trophozoites, particularly in the pseudopodia and food-cup. These results suggest that monoclonal antibodies produced against rNfCPB and rNfCPB-L proteins may be useful for further immunological study of PAM. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Efficacy and safety of trastuzumab emtansine (T-DM1) in the treatment of HER2-positive metastatic breast cancer (MBC): a meta-analysis of randomized controlled trial

    PubMed Central

    Yan, Hongjing; Yu, Kewei; Zhang, Kaile; Liu, Linxia; Li, Yue

    2017-01-01

    Aims Trastuzumab emtansine (T-DM1), an antibody-drug conjugate against human epidermal growth factor receptor 2 (HER2), has been used in the treatment of patients with HER2-positive metastatic breast cancer (MBC). We conducted a meta-analysis to evaluate the efficacy and toxicity of T-DM1 for the treatment of patients with HER2-positive MBC. Materials and Methods Randomized controlled trials (RCTs), published in Pubmed, Embase, and Web of Science were systematically reviewed to assess the survival benefits and toxicity profile of HER2-positive patients with MBC who were treated with T-DM1. Outcomes included progression-free survival (PFS), overall survival (OS), overall response rate (ORR), and toxicities. Results were expressed as the hazard ratio (HR) with 95% confidence intervals (CIs). Results A total of 5 RCTs involving 3,720 patients met the inclusion criteria and were included in this meta-analysis. T-DM1 significantly prolonged PFS (HR = 0.73, 95% CI: 0.61, 0.86; P < 0.05), OS (HR = 0.68, 95% CI: 0.62, 0.74; P < 0.05), but it did not increase ORR (RR = 1.25, 95% CI: 0.94, 1.66; P = 0.148). Subgroup analysis indicated that T-DM1 significantly improved PFS when it was used as first-line (HR = 0.86, 95% CI: 0.74, 1.00; P < 0.05) or non-first-line treatment (HR = 0.65, 95% CI: 0.53, 0.81; P < 0.05). T-DM1 was associated with more frequent adverse events, including fatigue, elevated ALT, elevated AST, and thrombocytopenia, than other anti-HER2 therapies. Conclusions Based on the current evidence, T-DM1 significantly prolonged PFS and OS with a tolerated toxicity than other anti-HER2 therapies in patients with HER2-positive MBC. These findings confirm the use of T-DM1 for the treatment of patients with HER2-positive MBC. Further well-designed, multi-center RCTs needed to identify these findings. PMID:29254261

  9. [Immunohistochemical assessment of HER2 expression in gastric cancer. A clinicopathologic study of 93 cases].

    PubMed

    Alvarado-Cabrero, Isabel; Gil-Hernández, Sara; Ruelas-Perea, Ana; Villaverde-Rodríguez, Diego; Montes-Ochoa, José Roberto; Medrano-Guzmán, Rafael

    Gastric cancer in Mexico is ranked third in both males and females. Most patients present clinically with advanced disease and treatment options are sparse. HER2 overexpression in gastric cancer is related to poor outcome. Immunohistochemical testing for HER2 is becoming the standard of care for guiding adjuvant treatment of gastric cancer with trastuzumab. To determine the frequency of HER2 overexpression in patients with gastric cancer in the Hospital de Oncología del Centro Médico Nacional, Siglo XXI and its association with other histopathological findings. Patients with gastric cancer who underwent surgery between March 12, 2006-August 31, 2011, were enrolled in this retrospective study. Diagnosis was confirmed by review of slides and immunohistochemistry with anti-HER2 antibody was performed. Scoring was done by Hoffman scoring system. Medical records were evaluated. Ninety-three patients were included in the study, with 43 (46.2%) male and 50 (53.7%) female patients. The median age was 64 years. HER2-positive tumours were identified in 6 patients (6.45%) and located most frequently in the proximal stomach. There was no difference in HER2 overexpression in relation to age, gender or histologic type. In our study, about 7% of patients with gastric cancer were HER2-positive on immunohistochemistry. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  10. Simultaneous targeting of EGFR, HER2, and HER4 by afatinib overcomes intrinsic and acquired cetuximab resistance in head and neck squamous cell carcinoma cell lines.

    PubMed

    De Pauw, Ines; Lardon, Filip; Van den Bossche, Jolien; Baysal, Hasan; Fransen, Erik; Deschoolmeester, Vanessa; Pauwels, Patrick; Peeters, Marc; Vermorken, Jan Baptist; Wouters, An

    2018-06-01

    The epidermal growth factor receptor (EGFR, HER1) is a therapeutic target in head and neck squamous cell carcinoma (HNSCC). After initial promising results with EGFR-targeted therapies such as cetuximab, therapeutic resistance has become a major clinical problem, and new treatment options are therefore necessary. Moreover, the relationship between HER receptors, anti-EGFR therapies, and the human papillomavirus (HPV) status in HNSCC is not fully understood. In contrast to first-generation EGFR inhibitors, afatinib irreversibly inhibits multiple HER receptors simultaneously. Therefore, treatment with afatinib might result in a more pronounced therapeutic benefit, even in patients experiencing cetuximab resistance. In this study, the cytotoxic effect of afatinib as single agent and in combination with cisplatin was investigated in cetuximab-sensitive, intrinsically cetuximab-resistant, and acquired cetuximab-resistant HNSCC cell lines with different HPV status under normoxia and hypoxia. Furthermore, the influence of cetuximab resistance, HPV, and hypoxia on the expression of HER receptors was investigated. Our results demonstrated that afatinib was able to establish cytotoxicity in cetuximab-sensitive, intrinsically cetuximab-resistant, and acquired cetuximab-resistant HNSCC cell lines, independent of the HPV status. However, cross-resistance between cetuximab and afatinib might be possible. Treatment with afatinib caused a G 0 /G 1 cell cycle arrest as well as induction of apoptotic cell death. Additive to antagonistic interactions between afatinib and cisplatin could be observed. Neither cetuximab resistance nor HPV status significantly influenced the expression of HER receptors in HNSCC cell lines. In contrast, the expression of EGFR, HER2, and HER3 was significantly altered under hypoxia. Oxygen deficiency is a common characteristic of HNSCC tumors, and these hypoxic tumor regions often contain cells that are more resistant to treatment. However, we observed

  11. Overexpression of HER2 in the pancreas promotes development of intraductal papillary mucinous neoplasms in mice.

    PubMed

    Shibata, Wataru; Kinoshita, Hiroto; Hikiba, Yohko; Sato, Takeshi; Ishii, Yasuaki; Sue, Soichiro; Sugimori, Makoto; Suzuki, Nobumi; Sakitani, Kosuke; Ijichi, Hideaki; Mori, Ryutaro; Endo, Itaru; Maeda, Shin

    2018-04-18

    Pancreatic ductal adenocarcinoma (PDA) has a 5-year survival rate of less than 5% and is the sixth leading cause of cancer death. Although KRAS mutations are one of the major driver mutations in PDA, KRAS mutation alone is not sufficient to induce invasive pancreatic cancer in mice model. HER2, also known as ERBB2, is a receptor tyrosine kinase, and overexpression of HER2 is associated with poor clinical outcomes in pancreatic cancer. However, no report has shown whether HER2 and its downstream signaling contributes to the pancreatic cancer development. By immunohistochemical analysis in human cases, HER2 protein expression was detected in 40% of PDAs and 29% of intraductal papillary mucinous carcinomas, another type of pancreatic cancer. In a mouse model, we showed overexpression of activated HER2 (HER2 NT ) in the pancreas, in which cystic neoplastic lesions resembling intraductal papillary mucinous neoplasm-like lesions in humans had developed. We also found that HER2 NT cooperated with oncogenic Kras to accelerate the development of pancreatic intraepithelial neoplasms. In addition, using pancreatic organoids in 3D cultures, we found that organoids cultured from HER2 NT /Kras double transgenic mice showed proliferative potential and tumorigenic ability cooperatively. HER2-signaling inhibition was suggested to be an new therapeutic target in some types of PDAs.

  12. Nonclinical evaluation of the serum pharmacodynamic biomarkers HGF and shed MET following dosing with the anti-MET monovalent monoclonal antibody onartuzumab.

    PubMed

    Mai, Elaine; Zheng, Zhong; Chen, Youjun; Peng, Jing; Severin, Christophe; Filvaroff, Ellen; Romero, Mally; Mallet, William; Kaur, Surinder; Gelzleichter, Thomas; Nijem, Ihsan; Merchant, Mark; Young, Judy C

    2014-02-01

    Onartuzumab, a humanized, monovalent monoclonal anti-MET antibody, antagonizes MET signaling by inhibiting binding of its ligand, hepatocyte growth factor (HGF). We investigated the effects of onartuzumab on cell-associated and circulating (shed) MET (sMET) and circulating HGF in vitro and nonclinically to determine their utility as pharmacodynamic biomarkers for onartuzumab. Effects of onartuzumab on cell-associated MET were assessed by flow cytometry and immunofluorescence. sMET and HGF were measured in cell supernatants and in serum or plasma from multiple species (mouse, cynomolgus monkey, and human) using plate-based immunoassays. Unlike bivalent anti-MET antibodies, onartuzumab stably associates with MET on the surface of cells without inducing MET internalization or shedding. Onartuzumab delayed the clearance of human xenograft tumor-produced sMET from the circulation of mice, and endogenous sMET in cynomolgus monkeys. In mice harboring MET-expressing xenograft tumors, in the absence of onartuzumab, levels of human sMET correlated with tumor size, and may be predictive of MET-expressing tumor burden. Because binding of sMET to onartuzumab in circulation resulted in increasing sMET serum concentrations due to reduced clearance, this likely renders sMET unsuitable as a pharmacodynamic biomarker for onartuzumab. There was no observed effect of onartuzumab on circulating HGF levels in xenograft tumor-bearing mice or endogenous HGF in cynomolgus monkeys. Although sMET and HGF may serve as predictive biomarkers for MET therapeutics, these data do not support their use as pharmacodynamic biomarkers for onartuzumab.

  13. Evaluation of HER-2/neu status in breast cancer specimens using immunohistochemistry (IHC) & fluorescence in-situ hybridization (FISH) assay.

    PubMed

    Goud, Kalal Iravathy; Dayakar, Seetha; Vijayalaxmi, Kolanupaka; Babu, Saidam Jangu; Reddy, P Vijay Anand

    2012-03-01

    Fluorescence in situ hybridization (FISH) is increasingly being recognized as the most accurate and predictive test for HER 2/neu gene amplification and response to therapy in breast cancer. In the present study we investigated HER-2/neu gene amplification by FISH in breast carcinoma tissue specimens and compared the results with that of immunohistochemical (IHC) analysis. A total of 90 breast carcinoma tissue samples were used for immunohistochemical (IHC) and FISH analysis. IHC was performed by using mouse monoclonal antibody to the intracellular domain of HER-2/neu protein. Each slide was scored in a blinded fashion by two pathologists according to the manufacturer's recommended criteria. FISH analysis was performed on paraffin embedded breast tumour tissue sections. The polysomy for centromere 17 (Spec green signal) was read as green signals less than 4 as moderate polysomy, and more than 4 as highly polysomy. Thirty of the 90 patients had negative results by IHC and FISH. Of the 28 patients with the score of 2+ by IHC, 20 were FISH positive for HER-2/neu gene amplification, three were FISH negative and five patients showed equivocal (1.8-2.2) results by FISH. These five cases were retested for IHC and FISH on different paraffin embedded tissue blocks, and all five were found positive for HER-2/neu gene amplification. Twenty five patients with the score of 3+ by IHC were FISH positive for HER-2/neu gene amplification (>2.2). Seven cases with the score of 3+ by IHC were FISH negative for HER-2/neu gene amplification (>2.2), and showed polysomy of chromosome number 17 high polysomy > 4. Our results indicated that HER-2/neu status by FISH should be performed in all cases of breast tumour with a 2+ score by IHC. Cases demonstrating a 3+ score by IHC may be subjected to FISH to rule out polysomy of chromosome 17 which could be falsely interpreted as HER-2/neu overexpression by IHC analysis. There is also a need for establishing a clinically validated cut-off value

  14. Evaluation of HER-2/neu status in breast cancer specimens using immunohistochemistry (IHC) & fluorescence in-situ hybridization (FISH) assay

    PubMed Central

    Goud, Kalal Iravathy; Dayakar, Seetha; Vijayalaxmi, Kolanupaka; Babu, Saidam Jangu; Vijay, Anand Reddy P.

    2012-01-01

    Background & objectives: Fluorescence in situ hybridization (FISH) is increasingly being recognized as the most accurate and predictive test for HER2/neu gene amplification and response to therapy in breast cancer. In the present study we investigated HER-2/neu gene amplification by FISH in breast carcinoma tissue specimens and compared the results with that of immunohistochemical (IHC) analysis. Methods: A total of 90 breast carcinoma tissue samples were used for immunohistochemical (IHC) and FISH analysis. IHC was performed by using mouse monoclonal antibody to the intracellular domain of HER-2/neu protein. Each slide was scored in a blinded fashion by two pathologists according to the manufacturer's recommended criteria. FISH analysis was performed on paraffin embedded breast tumour tissue sections. The polysomy for centromere 17 (Spec green signal) was read as green signals less than 4 as moderate polysomy, and more than 4 as highly polysomy. Results: Thirty of the 90 patients had negative results by IHC and FISH. Of the 28 patients with the score of 2+ by IHC, 20 were FISH positive for HER-2/neu gene amplification, three were FISH negative and five patients showed equivocal (1.8-2.2) results by FISH. These five cases were retested for IHC and FISH on different paraffin embedded tissue blocks, and all five were found positive for HER-2/neu gene amplification. Twenty five patients with the score of 3+ by IHC were FISH positive for HER-2/neu gene amplification (>2.2). Seven cases with the score of 3+ by IHC were FISH negative for HER-2/neu gene amplification (>2.2), and showed polysomy of chromosome number 17 high polysomy > 4. Interpretation & conclusions: Our results indicated that HER-2/neu status by FISH should be performed in all cases of breast tumour with a 2+ score by IHC. Cases demonstrating a 3+ score by IHC may be subjected to FISH to rule out polysomy of chromosome 17 which could be falsely interpreted as HER-2/neu overexpression by IHC analysis

  15. Tumor driven by gain-of-function HER2 H878Y mutant is highly sensitive to HER2 inhibitor

    PubMed Central

    Hu, Zexi; Hu, Yong; Liu, Xicheng; Xi, Rongwen; Zhang, Aiqun; Liu, Deruo; Xie, Qiang; Chen, Liang

    2015-01-01

    HER2, a well established oncogenic member of EGFR family, is among the most intensely investigated kinase drug targets. In contrast to hotspot mutations of EGFR, few mutations of HER2 locate in activation loop within kinase domain. We previously reported the molecular mechanism underlying hyper kinase activity of HER2H878Y, a mutation located in activation loop. However, its tumorigenicity in vivo and relevant therapeutics remain to be determined. Here, we report for the first time that HER2H878Y was tumorigenic in vivo in lung adenocarcinoma transgenic mouse model. Induced expression of HER2H878Y in lung epithelial compartments resulted in formation of poorly differentiated lung adenocarcinoma with bronchioloalveolar carcinoma (BAC) features. Strikingly, we found that these tumors depended on continuous expression of HER2H878Y for maintenance. Typical HER2 downstream signaling mediators, including PLCγ1, STAT5 and AKT, were hyperactivated in HER2H878Y driven lung tumors. More importantly, administration of HKI-272, a tyrosine kinase inhibitor (TKI), efficiently shrank HER2H878Y driven tumors in transgenic mouse model. Moreover, we found that combinational treatment with HKI272 and mTOR inhibitor, Rapamycin, showed a superior cytotoxicity to H878Y mutant transformed cells and enhanced activity to elicit apoptosis and inhibit growth in situ in tumorous area. Our work therefore showed that HER2H878Y mutant was a reasonable drug target. Hence, our work supported the assessment of HKI-272/rapamycin treatment in clinical trials. PMID:26375550

  16. Immunotherapy with a HER2-Targeting Listeria Induces HER2-Specific Immunity and Demonstrates Potential Therapeutic Effects in a Phase I Trial in Canine Osteosarcoma.

    PubMed

    Mason, Nicola J; Gnanandarajah, Josephine S; Engiles, Julie B; Gray, Falon; Laughlin, Danielle; Gaurnier-Hausser, Anita; Wallecha, Anu; Huebner, Margie; Paterson, Yvonne

    2016-09-01

    Recombinant Listeria vaccines induce tumor-specific T-cell responses that eliminate established tumors and prevent metastatic disease in murine cancer models. We used dogs with HER2/neu(+) appendicular osteosarcoma, a well-recognized spontaneous model for pediatric osteosarcoma, to determine whether a highly attenuated, recombinant Listeria monocytogenes expressing a chimeric human HER2/neu fusion protein (ADXS31-164) could safely induce HER2/neu-specific immunity and prevent metastatic disease. Eighteen dogs that underwent limb amputation or salvage surgery and adjuvant chemotherapy were enrolled in a phase I dose escalation clinical trial and received either 2 × 10(8), 5 × 10(8), 1 × 10(9), or 3.3 × 10(9) CFU of ADXS31-164 intravenously every 3 weeks for 3 administrations. Only low-grade, transient toxicities were observed. ADXS31-164 broke peripheral tolerance and induced antigen-specific IFNγ responses against the intracellular domain of HER2/neu in 15 of 18 dogs within 6 months of treatment. Furthermore, ADXS31-164 reduced the incidence of metastatic disease and significantly increased duration of survival time and 1-, 2-, and 3-year survival rates when compared with a historical control group with HER2/neu(+) appendicular osteosarcoma treated with amputation and chemotherapy alone. These findings demonstrate that ADXS31-164 administered in the setting of minimal residual disease can induce HER2/neu-specific immunity and may reduce the incidence of metastatic disease and prolong overall survival in a clinically relevant, spontaneous, large animal model of cancer. These findings, therefore, have important translational relevance for children with osteosarcoma and adults with other HER2/neu(+) cancers. Clin Cancer Res; 22(17); 4380-90. ©2016 AACR. ©2016 American Association for Cancer Research.

  17. A phase 1, randomized, placebo-controlled, dose-escalation study of an anti-IL-13 monoclonal antibody in healthy subjects and mild asthmatics

    PubMed Central

    Hodsman, Peter; Ashman, Claire; Cahn, Anthony; De Boever, Erika; Locantore, Nicholas; Serone, Adrian; Pouliquen, Isabelle

    2013-01-01

    AIMS IL-13 is implicated as an important mediator of the pathology of asthma. This first clinical study with GSK679586, a novel humanized anti-IL-13 IgG1 monoclonal antibody, evaluated the safety, pharmacokinetics and pharmacodynamics of escalating single and repeat doses of GSK679586. METHODS In this randomized, double-blind study, healthy subjects received single intravenous infusions of GSK679586 (0.005, 0.05, 0.5, 2.5, 10 mg kg−1) or placebo and mild intermittent asthmatics received two once monthly intravenous infusions of GSK679586 (2.5, 10, 20 mg kg−1) or placebo. RESULTS GSK679586 displayed approximately linear pharmacokinetics (based on AUC and Cmax) with limited accumulation upon repeat administration. In mild intermittent asthmatics, treatment with GSK679586 produced an increase in serum total IL-13 concentrations, indicative of GSK679586–IL-13 complex formation. Additionally, mean levels of exhaled nitric oxide (FeNO), a marker of pulmonary inflammation, were reduced relative to baseline at 2.5, 10 and 20 mg kg−1 doses of GSK679586 at both 2 weeks (19%, 44% and 52% decreases) and 8 weeks (29%, 55% and 42% decreases) after the second infusion. GSK679586 was well tolerated; the incidence of AEs was comparable across all presumed biologically active doses and there were no treatment-related SAEs. CONCLUSIONS GSK679586 demonstrated dose-dependent pharmacological activity in the lungs of mild intermittent asthmatics. These findings, together with the favourable safety profile and advantageous PK characteristics of a monoclonal antibody (e.g. a long half-life supporting less frequent dosing), warrant further investigation of GSK679586 in a broader asthma patient population. PMID:22616628

  18. The HER2 Signaling Network in Breast Cancer--Like a Spider in its Web.

    PubMed

    Dittrich, A; Gautrey, H; Browell, D; Tyson-Capper, A

    2014-12-01

    The human epidermal growth factor receptor 2 (HER2) is a major player in the survival and proliferation of tumour cells and is overexpressed in up to 30 % of breast cancer cases. A considerable amount of work has been undertaken to unravel the activity and function of HER2 to try and develop effective therapies that impede its action in HER2 positive breast tumours. Research has focused on exploring the HER2 activated phosphoinositide-3-kinase (PI3K)/AKT and rat sarcoma/mitogen-activated protein kinase (RAS/MAPK) pathways for therapies. Despite the advances, cases of drug resistance and recurrence of disease still remain a challenge to overcome. An important aspect for drug resistance is the complexity of the HER2 signaling network. This includes the crosstalk between HER2 and hormone receptors; its function as a transcription factor; the regulation of HER2 by protein-tyrosine phosphatases and a complex network of positive and negative feedback-loops. This review summarises the current knowledge of many different HER2 interactions to illustrate the complexity of the HER2 network from the transcription of HER2 to the effect of its downstream targets. Exploring the novel avenues of the HER2 signaling could yield a better understanding of treatment resistance and give rise to developing new and more effective therapies.

  19. Targeting HER2 aberrations as actionable drivers in lung cancers: phase II trial of the pan-HER tyrosine kinase inhibitor dacomitinib in patients with HER2-mutant or amplified tumors

    PubMed Central

    Kris, M. G.; Camidge, D. R.; Giaccone, G.; Hida, T.; Li, B. T.; O'Connell, J.; Taylor, I.; Zhang, H.; Arcila, M. E.; Goldberg, Z.; Jänne, P. A.

    2015-01-01

    Background HER2 mutations and amplifications have been identified as oncogenic drivers in lung cancers. Dacomitinib, an irreversible inhibitor of HER2, EGFR (HER1), and HER4 tyrosine kinases, has demonstrated activity in cell-line models with HER2 exon 20 insertions or amplifications. Here, we studied dacomitinib in patients with HER2-mutant or amplified lung cancers. Patients and methods As a prespecified cohort of a phase II study, we included patients with stage IIIB/IV lung cancers with HER2 mutations or amplification. We gave oral dacomitinib at 30–45 mg daily in 28-day cycles. End points included partial response rate, overall survival, and toxicity. Results We enrolled 30 patients with HER2-mutant (n = 26, all in exon 20 including 25 insertions and 1 missense mutation) or HER2-amplified lung cancers (n = 4). Three of 26 patients with tumors harboring HER2 exon 20 mutations [12%; 95% confidence interval (CI) 2% to 30%] had partial responses lasting 3+, 11, and 14 months. No partial responses occurred in four patients with tumors with HER2 amplifications. The median overall survival was 9 months from the start of dacomitinib (95% CI 7–21 months) for patients with HER2 mutations and ranged from 5 to 22 months with amplifications. Treatment-related toxicities included diarrhea (90%; grade 3/4: 20%/3%), dermatitis (73%; grade 3/4: 3%/0%), and fatigue (57%; grade 3/4: 3%/0%). One patient died on study likely due to an interaction of dacomitinib with mirtazapine. Conclusions Dacomitinib produced objective responses in patients with lung cancers with specific HER2 exon 20 insertions. This observation validates HER2 exon 20 insertions as actionable targets and justifies further study of HER2-targeted agents in specific HER2-driven lung cancers. ClinicalTrials.gov NCT00818441. PMID:25899785

  20. Vectored Intracerebral Immunization with the Anti-Tau Monoclonal Antibody PHF1 Markedly Reduces Tau Pathology in Mutant Tau Transgenic Mice.

    PubMed

    Liu, Wencheng; Zhao, Lingzhi; Blackman, Brittany; Parmar, Mayur; Wong, Man Ying; Woo, Thomas; Yu, Fangmin; Chiuchiolo, Maria J; Sondhi, Dolan; Kaminsky, Stephen M; Crystal, Ronald G; Paul, Steven M

    2016-12-07

    Passive immunization with anti-tau monoclonal antibodies has been shown by several laboratories to reduce age-dependent tau pathology and neurodegeneration in mutant tau transgenic mice. These studies have used repeated high weekly doses of various tau antibodies administered systemically for several months and have reported reduced tau pathology of ∼40-50% in various brain regions. Here we show that direct intrahippocampal administration of the adeno-associated virus (AAV)-vectored anti-phospho-tau antibody PHF1 to P301S tau transgenic mice results in high and durable antibody expression, primarily in neurons. Hippocampal antibody levels achieved after AAV delivery were ∼50-fold more than those reported following repeated systemic administration. In contrast to systemic passive immunization, we observed markedly reduced (≥80-90%) hippocampal insoluble pathological tau species and neurofibrillary tangles following a single dose of AAV-vectored PHF1 compared with mice treated with an AAV-IgG control vector. Moreover, the hippocampal atrophy observed in untreated P301S mice was fully rescued by treatment with the AAV-vectored PHF1 antibody. Vectored passive immunotherapy with an anti-tau monoclonal antibody may represent a viable therapeutic strategy for treating or preventing such tauopathies as frontotemporal dementia, progressive supranuclear palsy, or Alzheimer's disease. We have used an adeno-associated viral (AAV) vector to deliver the genes encoding an anti-phospho-tau monoclonal antibody, PHF1, directly to the brain of mice that develop neurodegeneration due to a tau mutation that causes frontotemporal dementia (FTD). When administered systemically, PHF1 has been shown to modestly reduce tau pathology and neurodegeneration. Since such antibodies do not readily cross the blood-brain barrier, we used an AAV vector to deliver antibody directly to the hippocampus and observed much higher antibody levels and a much greater reduction in tau pathology. Using