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Sample records for inhibits human tumor

  1. Bee venom inhibits growth of human cervical tumors in mice.

    PubMed

    Lee, Hye Lim; Park, Sang Ho; Kim, Tae Myoung; Jung, Yu Yeon; Park, Mi Hee; Oh, Sang Hyun; Yun, Hye Seok; Jun, Hyung Ok; Yoo, Hwan Soo; Han, Sang-Bae; Lee, Ung Soo; Yoon, Joo Hee; Song, Min Jong; Hong, Jin Tae

    2015-03-30

    We studied whether bee venom (BV) inhibits cervical tumor growth through enhancement of death receptor (DR) expressions and inactivation of nuclear factor kappa B (NF-κB) in mice. In vivo study showed that BV (1 mg/kg) inhibited tumor growth. Similar inhibitory effects of BV on cancer growth in primary human cervical cancer cells were also found. BV (1-5 μg/ml) also inhibited the growth of cancer cells, Ca Ski and C33Aby the induction of apoptotic cell death in a dose dependent manner. Agreed with cancer cell growth inhibition, expression of death receptors; FAS, DR3 and DR6, and DR downstream pro-apoptotic proteins including caspase-3 and Bax was concomitantly increased, but the NF-κB activity and the expression of Bcl-2 were inhibited by treatment with BV in tumor mice, human cancer cell and human tumor samples as well as cultured cancer cells. In addition, deletion of FAS, DR3 and DR6 by small interfering RNA significantly reversed BV-induced cell growth inhibitory effects as well as NF-κB inactivation. These results suggest that BV inhibits cervical tumor growth through enhancement of FAS, DR3 and DR6 expression via inhibition of NF-κB pathway. PMID:25730901

  2. SKI knockdown inhibits human melanoma tumor growth in vivo.

    PubMed

    Chen, Dahu; Lin, Qiushi; Box, Neil; Roop, Dennis; Ishii, Shunsuke; Matsuzaki, Koichi; Fan, Tao; Hornyak, Thomas J; Reed, Jon A; Stavnezer, Ed; Timchenko, Nikolai A; Medrano, Estela E

    2009-12-01

    The SKI protein represses the TGF-beta tumor suppressor pathway by associating with the Smad transcription factors. SKI is upregulated in human malignant melanoma tumors in a disease-progression manner and its overexpression promotes proliferation and migration of melanoma cells in vitro. The mechanisms by which SKI antagonizes TGF-beta signaling in vivo have not been fully elucidated. Here we show that human melanoma cells in which endogenous SKI expression was knocked down by RNAi produced minimal orthotopic tumor xenograft nodules that displayed low mitotic rate and prominent apoptosis. These minute tumors exhibited critical signatures of active TGF-beta signaling including high levels of nuclear Smad3 and p21(Waf-1), which are not found in the parental melanomas. To understand how SKI promotes tumor growth we used gain- and loss-of-function approaches and found that simultaneously to blocking the TGF-beta-growth inhibitory pathway, SKI promotes the switch of Smad3 from tumor suppression to oncogenesis by favoring phosphorylations of the Smad3 linker region in melanoma cells but not in normal human melanocytes. In this context, SKI is required for preventing TGF-beta-mediated downregulation of the oncogenic protein c-MYC, and for inducing the plasminogen activator inhibitor-1, a mediator of tumor growth and angiogenesis. Together, the results indicate that SKI exploits multiple regulatory levels of the TGF-beta pathway and its deficiency restores TGF-beta tumor suppressor and apoptotic activities in spite of the likely presence of oncogenic mutations in melanoma tumors. PMID:19845874

  3. Inhibition of subcutaneously implanted human pituitary tumor cells in nude mice by LRIG1.

    PubMed

    Wang, X; He, X J; Xu, H Q; Chen, Z W; Fan, H H

    2016-01-01

    The aim of this study was to explore the inhibition of subcutaneously implanted human pituitary tumor cells in nude mice by LRIG1 and its mechanism. For this study, athymic nude mice were injected with either normal pituitary tumor RC-4B/C cells or LRIG1-transfected RC-4B/C cells. We then calculated the volume inhibition rate of the tumors, as well as the apoptosis index of tumor cells and the expression of Ras, Raf, AKt, and ERK mRNA in tumor cells. Tumor cell morphological and structural changes were also observed under electron microscope. Our data showed that subcutaneous tumor growth was slowed or even halted in LRIG1-transfected tumors. The tumor volumes were significantly different between the two groups of mice (χ2 = 2.14, P < 0.05). The tumor apoptosis index was found to be 8.72% in the control group and 39.7% in LRIG1-transfected mice (χ2 = 7.59, P < 0.05). The levels of Ras, Raf, and AKt mRNA in LRIG1-transfected RC-4B/C cells were significantly reduced after transfection (P < 0.01). Transfected subcutaneous tumor cells appeared to be in early or late apoptosis under an electron microscope, while only a few subcutaneous tumor cells appeared to be undergoing apoptosis in the control group. In conclusion, the LRIG1 gene is able to inhibit proliferation and promote apoptosis in subcutaneously implanted human pituitary tumors in nude mice. The mechanism of LRIG1 may involve the inhibition of the PI3K/ Akt and Ras/Raf/ERK signal transduction pathways. PMID:27173312

  4. A humanized anti-DLL4 antibody promotes dysfunctional angiogenesis and inhibits breast tumor growth

    PubMed Central

    Jia, Xuelian; Wang, Wenyi; Xu, Zhuobin; Wang, Shijing; Wang, Tong; Wang, Min; Wu, Min

    2016-01-01

    Blockage of Delta-like 4 (DLL4)-directed Notch signaling induces excessive tip cell formation and endothelial proliferation resulting in dysfunctional angiogenesis in tumors. MMGZ01, as a murine anti-human DLL4 monoclonal antibody, specifically binds to human DLL4 and blocks Notch pathway. Here, the structure of MMGZ01 variable fragment (Fv) was established and framework region (FR) residues which supported complementarily determining region (CDR) loop conformation were identified. Important residues interactions were also identified through docking MMGZ01 Fv with antigen epitope in DLL4. To humanize the murine antibody, we modified MMGZ01 Fv through CDR grafting and the reconstructed antibody (H3L2) maintained similar structure and binding affinity to parental MMGZ01 after back mutation of 12 canonical murine residues in the FRs. Meanwhile, H3L2 promoted human umbilical vein endothelial cell (HUVEC) proliferation through inhibiting DLL4-directed Notch pathway. Moreover, in MDA-MB-231-bearing nude mice, H3L2 induced dysfunctional angiogenesis and tumor cell apoptosis and showed superior anti-tumor activity. In conclusion, H3L2 is an ideal humanized antibody that inhibits tumor growth through targeting DLL4-Notch pathway and has attracting potentials for clinical applications. PMID:27301650

  5. A humanized anti-DLL4 antibody promotes dysfunctional angiogenesis and inhibits breast tumor growth.

    PubMed

    Jia, Xuelian; Wang, Wenyi; Xu, Zhuobin; Wang, Shijing; Wang, Tong; Wang, Min; Wu, Min

    2016-01-01

    Blockage of Delta-like 4 (DLL4)-directed Notch signaling induces excessive tip cell formation and endothelial proliferation resulting in dysfunctional angiogenesis in tumors. MMGZ01, as a murine anti-human DLL4 monoclonal antibody, specifically binds to human DLL4 and blocks Notch pathway. Here, the structure of MMGZ01 variable fragment (Fv) was established and framework region (FR) residues which supported complementarily determining region (CDR) loop conformation were identified. Important residues interactions were also identified through docking MMGZ01 Fv with antigen epitope in DLL4. To humanize the murine antibody, we modified MMGZ01 Fv through CDR grafting and the reconstructed antibody (H3L2) maintained similar structure and binding affinity to parental MMGZ01 after back mutation of 12 canonical murine residues in the FRs. Meanwhile, H3L2 promoted human umbilical vein endothelial cell (HUVEC) proliferation through inhibiting DLL4-directed Notch pathway. Moreover, in MDA-MB-231-bearing nude mice, H3L2 induced dysfunctional angiogenesis and tumor cell apoptosis and showed superior anti-tumor activity. In conclusion, H3L2 is an ideal humanized antibody that inhibits tumor growth through targeting DLL4-Notch pathway and has attracting potentials for clinical applications. PMID:27301650

  6. Extract of Cordyceps militaris inhibits angiogenesis and suppresses tumor growth of human malignant melanoma cells.

    PubMed

    Ruma, I Made Winarsa; Putranto, Endy Widya; Kondo, Eisaku; Watanabe, Risayo; Saito, Ken; Inoue, Yusuke; Yamamoto, Ken-Ichi; Nakata, Susumu; Kaihata, Masaji; Murata, Hitoshi; Sakaguchi, Masakiyo

    2014-07-01

    Angiogenesis is essential for tumor development and metastasis. Among several angiogenic factors, vascular endothelial growth factor receptor (VEGF) is important for tumor-derived angiogenesis and commonly overexpressed in solid tumors. Thus, many antitumor strategies targeting VEGF have been developed to inhibit cancer angiogenesis, offering insights into the successful treatment of solid cancers. However, there are a number of issues such as harmful effects on normal vascularity in clinical trials. Taking this into consideration, we employed Cordyceps militaris as an antitumor approach due to its biological safety in vivo. The herbal medicinal mushroom Cordyceps militaris has been reported to show potential anticancer properties including anti-angiogenic capacity; however, its concrete properties have yet to be fully demonstrated. In this study, we aimed to elucidate the biological role of Cordyceps militaris extract in tumor cells, especially in regulating angiogenesis and tumor growth of a human malignant melanoma cell line. We demonstrated that Cordyceps militaris extract remarkably suppressed tumor growth via induction of apoptotic cell death in culture that links to the abrogation of VEGF production in melanoma cells. This was followed by mitigation of Akt1 and GSK-3β activation, while p38α phosphorylation levels were increased. Extract treatment in mouse model xenografted with human melanoma cells resulted in a dramatic antitumor effect with down-regulation of VEGF expression. The results suggest that suppression of tumor growth by Cordyceps militaris extract is, at least, mediated by its anti-angiogenicity and apoptosis induction capacities. Cordyceps militaris extract may be a potent antitumor herbal drug for solid tumors. PMID:24789042

  7. Berberine inhibits human tongue squamous carcinoma cancer tumor growth in a murine xenograft model.

    PubMed

    Ho, Yung-Tsuan; Yang, Jai-Sing; Lu, Chi-Cheng; Chiang, Jo-Hua; Li, Tsai-Chung; Lin, Jen-Jyh; Lai, Kuang-Chi; Liao, Ching-Lung; Lin, Jaung-Geng; Chung, Jing-Gung

    2009-09-01

    Our primary studies showed that berberine induced apoptosis in human tongue cancer SCC-4 cells in vitro. But there is no report to show berberine inhibited SCC-4 cancer cells in vivo on a murine xenograft animal model. SCC-4 tumor cells were implanted into mice and groups of mice were treated with vehicle, berberine (10mg/kg of body weight) and doxorubicin (4mg/kg of body weight). The tested agents were injected once per four days intraperitoneally (i.p.), with treatment starting 4 weeks prior to cells inoculation. Treatment with 4mg/kg of doxorubicin or with 10mg/kg of berberine resulted in a reduction in tumor incidence. Tumor size in xenograft mice treated with 10mg/kg berberine was significantly smaller than that in the control group. Our findings indicated that berbeirne inhibits tumor growth in a xenograft animal model. Therefore, berberine may represent a tongue cancer preventive agent and can be used in clinic. PMID:19303753

  8. Direct tumor recognition by a human CD4+ T-cell subset potently mediates tumor growth inhibition and orchestrates anti-tumor immune responses

    PubMed Central

    Matsuzaki, Junko; Tsuji, Takemasa; Luescher, Immanuel F.; Shiku, Hiroshi; Mineno, Junichi; Okamoto, Sachiko; Old, Lloyd J.; Shrikant, Protul; Gnjatic, Sacha; Odunsi, Kunle

    2015-01-01

    Tumor antigen-specific CD4+ T cells generally orchestrate and regulate immune cells to provide immune surveillance against malignancy. However, activation of antigen-specific CD4+ T cells is restricted at local tumor sites where antigen-presenting cells (APCs) are frequently dysfunctional, which can cause rapid exhaustion of anti-tumor immune responses. Herein, we characterize anti-tumor effects of a unique human CD4+ helper T-cell subset that directly recognizes the cytoplasmic tumor antigen, NY-ESO-1, presented by MHC class II on cancer cells. Upon direct recognition of cancer cells, tumor-recognizing CD4+ T cells (TR-CD4) potently induced IFN-γ-dependent growth arrest in cancer cells. In addition, direct recognition of cancer cells triggers TR-CD4 to provide help to NY-ESO-1-specific CD8+ T cells by enhancing cytotoxic activity, and improving viability and proliferation in the absence of APCs. Notably, the TR-CD4 either alone or in collaboration with CD8+ T cells significantly inhibited tumor growth in vivo in a xenograft model. Finally, retroviral gene-engineering with T cell receptor (TCR) derived from TR-CD4 produced large numbers of functional TR-CD4. These observations provide mechanistic insights into the role of TR-CD4 in tumor immunity, and suggest that approaches to utilize TR-CD4 will augment anti-tumor immune responses for durable therapeutic efficacy in cancer patients. PMID:26447332

  9. Thymic stromal lymphopoietin (TSLP) inhibits human colon tumor growth by promoting apoptosis of tumor cells

    PubMed Central

    Yang, Xuguang; Li, Bingji; Liu, Jie; He, Rui

    2016-01-01

    Thymic stromal lymphopoietin (TSLP) has recently been suggested in several epithelial cancers, either pro-tumor or anti-tumor. However, the role of TSLP in colon cancer remains unknown. We here found significantly decreased TSLP levels in tumor tissues compared with tumor-surrounding tissues of patients with colon cancer and TSLP levels negatively correlated with the clinical staging score of colon cancer. TSLPR, the receptor of TSLP, was expressed in all three colon cancer cell lines investigated and colon tumor tissues. The addition of TSLP significantly enhanced apoptosis of colon cancer cells in a TSLPR-dependent manner. Interestingly, TSLP selectively induced the apoptosis of colon cancer cells, but not normal colonic epithelial cells. Furthermore, we demonstrated that TSLP induced JNK and p38 activation and initiated apoptosis mainly through the extrinsic pathway, as caspase-8 inhibitor significantly reversed the apoptosis-promoting effect of TSLP. Finally, using a xenograft mouse model, we demonstrated that peritumoral administration of TSLP greatly reduced tumor growth accompanied with extensive tumor apoptotic response, which was abolished by tumor cell-specific knockdown of TSLPR. Collectively, our study reveals a novel anti-tumor effect of TSLP via direct promotion of the apoptosis of colon cancer cells, and suggests that TSLP could be of value in treating colon cancer. PMID:26919238

  10. Gallium maltolate inhibits human cutaneous T-cell lymphoma tumor development in mice.

    PubMed

    Wu, Xuesong; Wang, Timothy W; Lessmann, George M; Saleh, Jamal; Liu, Xiping; Chitambar, Christopher R; Hwang, Sam T

    2015-03-01

    Cutaneous T-cell lymphomas (CTCLs) represent a heterogeneous group of non-Hodgkin's lymphoma characterized by an accumulation of malignant CD4 T cells in the skin. The group IIIa metal salt, gallium nitrate, is known to have antineoplastic activity against B-cell lymphoma in humans, but its activity in CTCLs has not been elaborated in detail. Herein, we examined the antineoplastic efficacy of a gallium compound, gallium maltolate (GaM), in vitro and in vivo with murine models of CTCLs. GaM inhibited cell growth and induced apoptosis of cultured CTCL cells. In human CTCL xenograft models, peritumoral injection of GaM limited the growth of CTCL cells, shown by fewer tumor formations, smaller tumor sizes, and decreased neovascularization in tumor microenvironment. To identify key signaling pathways that have a role in GaM-mediated reduction of tumor growth, we analyzed inflammatory cytokines, as well as signal transduction pathways in CTCL cells treated by GaM. IFN-γ-induced chemokines and IL-13 were found to be notably increased in GaM-treated CTCL cells. However, immunosuppressive cytokines, such as IL-10, were decreased with GaM treatment. Interestingly, both oxidative stress and p53 pathways were involved in GaM-induced cytotoxicity. These results warrant further investigation of GaM as a therapeutic agent for CTCLs. PMID:25371972

  11. Picropodophyllin inhibits tumor growth of human nasopharyngeal carcinoma in a mouse model

    SciTech Connect

    Yin, Shu-Cheng; Guo, Wei; Tao, Ze-Zhang

    2013-09-13

    Highlights: •We identified that PPP inhibits IGF-1R/Akt pathway in NPC cells. •PPP dose-dependently inhibits NPC cell proliferation in vitro. •PPP suppresses tumor growth of NPC in nude mice. •PPP have little effect on microtubule assembly. -- Abstract: Insulin-like growth factor-1 receptor (IGF-1R) is a cell membrane receptor with tyrosine kinase activity and plays important roles in cell transformation, tumor growth, tumor invasion, and metastasis. Picropodophyllin (PPP) is a selective IGF-1R inhibitor and shows promising antitumor effects for several human cancers. However, its antitumor effects in nasopharyngeal carcinoma (NPC) remain unclear. The purpose of this study is to investigate the antitumor activity of PPP in NPC using in vitro cell culture and in vivo animal model. We found that PPP dose-dependently decreased the IGF-induced phosphorylation and activity of IGF-1R and consequently reduced the phosphorylation of Akt, one downstream target of IGF-1R. In addition, PPP inhibited NPC cell proliferation in vitro. The half maximal inhibitory concentration (IC50) of PPP for NPC cell line CNE-2 was ⩽1 μM at 24 h after treatment and ⩽0.5 μM at 48 h after treatment, respectively. Moreover, administration of PPP by intraperitoneal injection significantly suppressed the tumor growth of xenografted NPC in nude mice. Taken together, these results suggest targeting IGF-1R by PPP may represent a new strategy for treatment of NPCs with positive IGF-1R expression.

  12. Local anesthetics inhibit kinesin motility and microtentacle protrusions in human epithelial and breast tumor cells.

    PubMed

    Yoon, Jennifer R; Whipple, Rebecca A; Balzer, Eric M; Cho, Edward H; Matrone, Michael A; Peckham, Michelle; Martin, Stuart S

    2011-10-01

    Detached breast tumor cells produce dynamic microtubule protrusions that promote reattachment of cells and are termed tubulin microtentacles (McTNs) due to their mechanistic distinctions from actin-based filopodia/invadopodia and tubulin-based cilia. McTNs are enriched with vimentin and detyrosinated α-tubulin, (Glu-tubulin). Evidence suggests that vimentin and Glu-tubulin are cross-linked by kinesin motor proteins. Using known kinesin inhibitors, Lidocaine and Tetracaine, the roles of kinesins in McTN formation and function were tested. Live-cell McTN counts, adhesion assays, immunofluorescence, and video microscopy were performed to visualize inhibitor effects on McTNs. Viability and apoptosis assays were used to confirm the non-toxicity of the inhibitors. Treatments of human non-tumorigenic mammary epithelial and breast tumor cells with Lidocaine or Tetracaine caused rapid collapse of vimentin filaments. Live-cell video microscopy demonstrated that Tetracaine reduces motility of intracellular GFP-kinesin and causes centripetal collapse of McTNs. Treatment with Tetracaine inhibited the extension of McTNs and their ability to promote tumor cell aggregation and reattachment. Lidocaine showed similar effects but to a lesser degree. Our current data support a model in which the inhibition of kinesin motor proteins by Tetracaine leads to the reductions in McTNs, and provides a novel mechanism for the ability of this anesthetic to decrease metastatic progression. PMID:21069453

  13. FBXW7 acts as an independent prognostic marker and inhibits tumor growth in human osteosarcoma.

    PubMed

    Li, Zhanchun; Xiao, Jie; Hu, Kongzu; Wang, Gang; Li, Maoqiang; Zhang, Jidong; Cheng, Guangqi

    2015-01-01

    F-box and WD repeat domain-containing 7 (FBXW7) is a potent tumor suppressor in human cancers including breast cancer, colorectal cancer, gastric cancer and hepatocellular carcinoma. In this study, we found that the expressions of FBXW7 protein and mRNA levels in osteosarcoma (OS) cases were significantly lower than those in normal bone tissues. Clinical analysis indicated that FBXW7 was expressed at lower levels in OS patients with advanced clinical stage, high T classification and poor histological differentiation. Furthermore, we demonstrated that high expression of FBXW7 was correlated with a better 5-year survival of OS patients. Multivariate Cox regression analysis indicated that FBXW7 was an independent prognostic marker in OS. Our in vitro studies showed that FBXW7 overexpression inhibited cell cycle transition and cell proliferation, and promoted apoptosis in both U2OS and MG-63 cells. In a nude mouse xenograft model, FBXW7 overexpression slowed down tumor growth by inducing apoptosis and growth arrest. Mechanistically, FBXW7 inversely regulated oncoprotein c-Myc and cyclin E levels in both U2OS and MG-63 cells. Together these findings suggest that FBXW7 may serve as a prognostic biomarker and inhibit tumor progression by inducing apoptosis and growth arrest in OS. PMID:25622249

  14. Pertussis toxin inhibits somatostatin-induced K/sup +/ conductance in human pituitary tumor cells

    SciTech Connect

    Yamashita, N.; Kojima, I.; Shibuya, N.; Ogata, E.

    1987-07-01

    The effect of pertussis toxin on somatostatin-induced K/sup +/ current was examined in dissociated human pituitary tumor cells obtained from two acromegalic patients. Somatostatin-induced hyperpolarization or K/sup +/ current was observed in 20 of 23 cells in adenoma 1 and 10 of 11 cells in adenoma 2. After treatment with pertussis toxin for 24 h, these responses were completely suppressed (0/14 in adenoma, 1, 0/10 in adenoma 2). Spontaneous action potentials, K/sup +/, Na/sup +/, and Ca/sup 2 +/ currents were well preserved after pertussis toxin treatment. When crude membrane fraction was incubated with (/sup 32/P)NAD, a 41K protein was ADP-ribosylated by pertussis toxin. Hormone release was inhibited by somatostatin and this inhibition was blocked by pertussis toxin treatment.

  15. Fully humanized neutralizing antibodies to interleukin-8 (ABX-IL8) inhibit angiogenesis, tumor growth, and metastasis of human melanoma.

    PubMed

    Huang, Suyun; Mills, Lisa; Mian, Badar; Tellez, Carmen; McCarty, Marya; Yang, X-D; Gudas, Jean M; Bar-Eli, Menashe

    2002-07-01

    Interleukin-8 (IL-8) has recently been shown to contribute to human melanoma progression by functioning as a mitogenic and angiogenic factor. In the present study, we investigated whether targeting IL-8 by a fully human anti-IL-8 antibody (ABX-IL8) could be a potential therapeutic strategy to control angiogenesis, growth, and metastasis of melanoma. The human melanoma cells A375SM (high IL-8 producer) and TXM-13 (intermediate IL-8 producer) were injected subcutaneously into nude mice, which were then treated with ABX-IL8 (1 mg/3 times weekly, i.p., for 3 weeks). Tumor growth of both melanomas in ABX-IL8-treated mice was significantly inhibited when compared with control IgG-treated animals. ABX-IL8 treatment also suppressed experimental metastasis when the melanoma cells were injected intravenously. IL-8 blockade by ABX-IL8 significantly inhibited the promoter activity and the collagenase activity of matrix metalloproteinase-2 in human melanoma cells, resulting in decreased invasion through reconstituted basement membrane in vitro. In vivo, ABX-IL8 treatment resulted in decreased expression of matrix metalloproteinase-2, and decreased vascularization (angiogenesis) of tumors concomitant with increased apoptosis of tumor cells. Moreover, in an in vitro vessel formation assay, ABX-IL8 directly interfered with the tubule formation by human umbilical vein endothelial cells. Taken together, these results point to the potential utility of ABX-IL8 as a modality to treat melanoma and other solid tumors either alone or in combination with conventional chemotherapy or other anti-tumor agents. PMID:12107097

  16. Pit-1 inhibits BRCA1 and sensitizes human breast tumors to cisplatin and vitamin D treatment

    PubMed Central

    Seoane, Samuel; Arias, Efigenia; Sigueiro, Rita; Sendon-Lago, Juan; Martinez-Ordoñez, Anxo; Castelao, Esteban; Eiró, Noemí; Garcia-Caballero, Tomás; Macia, Manuel; Lopez-Lopez, Rafael; Maestro, Miguel; Vizoso, Francisco; Mouriño, Antonio; Perez-Fernandez, Roman

    2015-01-01

    The POU class 1 homeobox 1 (POU1F1, also known as Pit-1), pertaining to the Pit-Oct-Unc (POU) family of transcription factors, has been related to tumor growth and metastasis in breast. However, its role in response to breast cancer therapy is unknown. We found that Pit-1 down-regulated DNA-damage and repair genes, and specifically inhibited BRCA1 gene expression, sensitizing breast cancer cells to DNA-damage agents. Administration of 1α, 25-dihydroxy-3-epi-vitamin D3 (3-Epi, an endogenous low calcemic vitamin D metabolite) reduced Pit-1 expression, and synergized with cisplatin, thus, decreasing cell proliferation and apoptosis in vitro, and reducing tumor growth in vivo. In addition, fifteen primary cultures of human breast tumors showed significantly decreased proliferation when treated with 3-Epi+cisplatin, compared to cisplatin alone. This response positively correlated with Pit-1 levels. Our findings demonstrate that high levels of Pit-1 and reduced BRCA1 levels increase breast cancer cell susceptibility to 3-Epi+cisplatin therapy. PMID:25992773

  17. Emodin inhibits HMGB1-induced tumor angiogenesis in human osteosarcoma by regulating SIRT1

    PubMed Central

    Qu, Wei; Wang, Yufei; Wu, Qining; Liu, Jijun; Hao, Dingjun

    2015-01-01

    The anti-cancer effects of emodin, including inhibition of proliferation, invasion, metastasis and angiogenesis, were confirmed by various previous studies. However, the specific mechanisms were not clear. In this study, we investigated emodin’s anti-angiogenesis effect and focused on the mechanisms in human osteosarcoma (OS). OS cells were implanted to nude mice to form OS xenografts. Immunofluorescence assay was used to assess vWF expression in tumor tissue. MTT assay was employed to screen proper emodin concentrations unrelated with proliferation inhibition. siRNA technique was utilized to silence SIRT1 expression in OS cells. Expression levels of SIRT1 and VEGF were investigated by real-time PCR and western blotting. H4-k16Ac expression which indicated the deacetylation activity of SIRT1 was also detected by western blotting. As in results, HMGB1 treatment exacerbated OS angiogenesis both in vivo and in vitro. Emodin administration attenuated angiogenesis in both OS and HMGB1 treated OS in vivo and in vitro. After emodin treatment, the expression level and deacetylation activity of SIRT1 were dramatically enhanced. HMGB1-induced angiogenesis was more striking in SIRT1 silenced OS cells. SIRT1 silencing also impaired the anti-angiogenesis effect of emodin in OS cells. In conclusion: SIRT expression and deacetylation activity elevation are involved in emodin’s anti-angiogenesis effect in human OS. PMID:26628989

  18. Sensitivity of human granulosa cell tumor cells to epidermal growth factor receptor inhibition.

    PubMed

    Andersson, Noora; Anttonen, Mikko; Färkkilä, Anniina; Pihlajoki, Marjut; Bützow, Ralf; Unkila-Kallio, Leila; Heikinheimo, Markku

    2014-04-01

    Epidermal growth factor receptor (EGFR) is implicated in the progression of many human cancers, but its significance in ovarian granulosa cell tumor (GCT) pathobiology remains poorly understood. We assessed the EGFR gene copy number, surveyed the mRNA and protein expression patterns of EGFR in 90 adult GCTs, and assessed the in vitro sensitivity of GCT cells to EGFR inhibition. Low-level amplification of EGFR gene was observed in five GCTs and high-level amplification in one sample. EGFR mRNA was robustly expressed in GCTs. Most tumors expressed both unphosphorylated and phosphorylated EGFR protein, but the protein expression did not correlate with clinical parameters, including the risk of recurrence. Small-molecule EGFR inhibitors reduced the EGF-induced activation of EGFR and its downstream signaling molecules at nanomolar doses, but cell viability was reduced, and caspase-3/7 was activated in GCT cells only at micromolar doses. Based on the present results, EGFR is active and abundantly expressed in the majority of GCTs, but probably has only minor contribution to GCT cell growth. Given the high doses of EGFR inhibitors required to reduce GCT cell viability in vitro, they are not likely to be effective for GCT treatment as single agents; they should rather be tested as part of combination therapies for these malignancies. PMID:24463098

  19. Avastin® in combination with gemcitabine and cisplatin significantly inhibits tumor angiogenesis and increases the survival rate of human A549 tumor-bearing mice

    PubMed Central

    LIU, YING; XIA, XIZHENG; ZHOU, MINGKAI; LIU, XIAOJUN

    2015-01-01

    The aim of this study was to investigate the effect of Avastin® in combination with gemcitabine and cisplatin (GP) on the tumor growth of A549 tumor-bearing mice and the potential anti-tumor mechanism. A total of 30 human A549 tumor-bearing nude mice were randomly divided into the Avastin, chemotherapy and combined treatment groups for treatment with an intraperitoneal injection of Avastin (5 mg/kg) (Avastin group); an intraperitoneal injection of gemcitabine (4 mg/kg) and cisplatin (4 mg/kg) (chemotherapy group); or intraperitoneal injections of Avastin and GP (combined treatment group). The mice were observed for 30 days and the tumor growth, survival and body weight of the mice in the three groups were analyzed. The protein level of vascular endothelial growth factor (VEGF) in the tumor tissues was analyzed by ELISA. The vascular density and structural changes of the tumor were analyzed using immunohistochemistry. Compared with the Avastin and chemotherapy groups, the tumor growth of mice in the combined treatment group was significantly inhibited, and the survival rate of the mice was increased significantly. No difference in body weight was observed among the three groups of mice (P>0.05). The levels of VEGF in the combined treatment group tumor tissues were significantly reduced compared with those in the chemotherapy group tumor tissues (P<0.05). Furthermore, the vessel density of the tumor tissue in the combined treatment group was significantly reduced compared with that in the chemotherapy group (P<0.05), and the number of normal vessels in the combined treatment group tumors was significantly higher than that in the chemotherapy group tumors after 7 days of treatment (P<0.05). In conclusion, Avastin can significantly decrease the level of VEGF in tumor tissue, inhibit tumor angiogenesis and promote the normalization of tumor vascular structure, which may explain the enhanced efficacy of Avastin in combination with chemotherapy. PMID:26136956

  20. Sulindac sulfide selectively inhibits growth and induces apoptosis of human breast tumor cells by PDE5 inhibition, elevation of cGMP, and activation of PKG

    PubMed Central

    Tinsley, Heather N.; Gary, Bernard D.; Keeton, Adam B.; Zhang, Wei; Abadi, Ashraf H.; Reynolds, Robert C.; Piazza, Gary A.

    2009-01-01

    Sulindac displays promising antineoplastic activity, but toxicities from cyclooxygenase (COX) inhibition limit its use for chemoprevention. Previous reports suggest that its anticancer properties may be attributed to a COX-independent mechanism, although alternative targets have not been well defined. Here we show that sulindac sulfide (SS) induces apoptosis and inhibits the growth of human breast tumor cells with IC50 values of 60-85 μM. Within the same concentration range, SS inhibited cGMP hydrolysis in tumor cell lysates, but did not affect cAMP hydrolysis. SS did not induce apoptosis of normal human mammary epithelial cells (HMEC), nor did it inhibit PDE activity in HMEC lysates. SS increased intracellular cGMP levels and activated protein kinase G in breast tumor cells, but not HMEC. The guanylyl cyclase (GC) activator, NOR-3, and cGMP PDE inhibitors, trequinsin and MY5445, displayed similar growth inhibitory activity as SS, but the adenylyl cyclase activator, forskolin, and other PDE inhibitors had no effect. Moreover, GC activation increased the sensitivity of tumor cells to SS, while GC inhibition reduced sensitivity. By comparing PDE isozyme profiles in breast tumor cells with HMEC and determining the sensitivity of recombinant PDE isozymes to SS, PDE5 was found to be overexpressed in breast tumor cells and selectively inhibited by SS. The mechanism of SS binding to the catalytic domain of PDE5 was revealed by molecular modeling. These data suggest that PDE5 inhibition is responsible for the breast tumor cell growth inhibitory and apoptosis inducing activity of SS and may contribute to the chemopreventive properties of sulindac. PMID:19996273

  1. CD47 blockade inhibits tumor progression human osteosarcoma in xenograft models

    PubMed Central

    Zhang, Shui-Jun; Zhao, Chen; Qiu, Bin-Song; Gu, Hai-Feng; Hong, Jian-Fei; Cao, Li; Chen, Yu; Xia, Bing; Bi, Qin; Wang, Ya-Ping

    2015-01-01

    Osteosarcoma is the most common bone tumors in children and adolescents. Despite intensive chemotherapy, patients with advanced disease still have a poor prognosis, illustrating the need for alternative therapies. In this study, we explored the use of antibodies that block CD47 with a tumor growth suppressive effect on osteosarcoma. We first found that up-regulation of CD47 mRNA levels in the tumorous tissues from eight patients with osteosarcoma when compared with that in adjacent non-tumorous tissues. Further western-blot (WB) and immunohistochemistry (IHC) demonstrated that CD47 protein level was highly expressed in osteosarcoma compared to normal osteoblastic cells and adjacent non-tumorous tissues. Osteosarcoma cancer stem cell markers staining shown that the majority of CD44+ cells expressed CD47 albeit with different percentages (ranging from 80% to 99%). Furthermore, high CD47 mRNA expression levels were associated with a decreased probability of progression-free and overall survival. In addition, blockade of CD47 by specific Abs suppresses the invasive ability of osteosarcoma tumor cells and further inhibits spontaneous pulmonary metastasis of KRIB osteosarcoma cells in vivo. Finally, CD47 blockade increases macrophage phagocytosis of osteosarcoma tumor cells. In conclusion, our findings demonstrate that CD47 is a critical regulator in the metastasis of osteosarcoma and suggest that targeted inhibition of this antigen by anti-CD47 may be a novel immunotherapeutic approach in the management of this tumor. PMID:26093091

  2. c-Myc depletion inhibits proliferation of human tumor cells at various stages of the cell cycle

    PubMed Central

    Wang, H; Mannava, S; Grachtchouk, V; Zhuang, D; Soengas, MS; Gudkov, AV; Prochownik, EV; Nikiforov, MA

    2011-01-01

    A major role for c-Myc in the proliferation of normal cells is attributed to its ability to promote progression through G1 and into S phase of the cell cycle. The absolute requirement of c-Myc for cell cycle progression in human tumor cells has not been comprehensively addressed. In the present work, we used a lentiviral-based short hairpin RNA (shRNA) expression vector to stably reduce c-Myc expression in a large number of human tumor cell lines and in three different types of normal human cells. In all cases, cell proliferation was severely inhibited, with normal cells ultimately undergoing G0/G1 growth arrest. In contrast, tumor cells demonstrated a much more variable cell cycle response with cells from several lines accumulating in S or G2/M phases. Moreover, in some tumor lines, the phase of cell cycle arrest caused by inhibition of c-Myc could be altered by depleting tumor suppressor protein p53 or its transcriptional target p21CIP/WAF. Our data suggest that, as in the case of normal cells, c-Myc is essential for sustaining proliferation of human tumor cells. However its rate-limiting role in cell cycle control is variable and is reliant upon the status of other cell cycle regulators. PMID:17906696

  3. EF24 inhibits tumor growth and metastasis via suppressing NF-kappaB dependent pathways in human cholangiocarcinoma

    PubMed Central

    Yin, Da-long; Liang, Ying-jian; Zheng, Tong-sen; Song, Rui-peng; Wang, Jia-bei; Sun, Bo-shi; Pan, Shang-ha; Qu, Lian-dong; Liu, Jia-ren; Jiang, Hong-chi; Liu, Lian-xin

    2016-01-01

    A synthetic monoketone analog of curcumin, termed 3, 5-bis (2-flurobenzylidene) piperidin-4-one (EF24), has been reported to inhibit the growth of a variety of cancer cells both in vitro and in vivo. However, whether EF24 has anticancer effects on cholangiocarcinoma (CCA) cells and the mechanisms remain to be investigated. The aim of our study was to evaluate the molecular mechanisms underlying the anticancer effects of EF24 on CCA tumor growth and metastasis. Cell proliferation, apoptosis, migration, invasion, tumorigenesis and metastasis were examined. EF24 exhibited time- and dose-dependent inhibitory effects on HuCCT-1, TFK-1 and HuH28 human CCA cell lines. EF24 inhibited CCA cell proliferation, migration, and induced G2/M phase arrest. EF24 induced cell apoptosis along with negative regulation of NF-κB- X-linked inhibitor of apoptosis protein (XIAP) signaling pathway. XIAP inhibition by lentivirus mediated RNA interference enhanced EF24-induced apoptosis, while XIAP overexpression reduced it in CCA cells. In vivo, EF24 significantly suppressed the growth of CCA tumor xenografts and tumor metastasis while displaying low toxicity levels. Our findings indicate that EF24 is a potent antitumor agent that inhibits tumor growth and metastasis by inhibiting NF-κB dependent signaling pathways. EF24 may represent a novel approach for CCA treatment. PMID:27571770

  4. EF24 inhibits tumor growth and metastasis via suppressing NF-kappaB dependent pathways in human cholangiocarcinoma.

    PubMed

    Yin, Da-Long; Liang, Ying-Jian; Zheng, Tong-Sen; Song, Rui-Peng; Wang, Jia-Bei; Sun, Bo-Shi; Pan, Shang-Ha; Qu, Lian-Dong; Liu, Jia-Ren; Jiang, Hong-Chi; Liu, Lian-Xin

    2016-01-01

    A synthetic monoketone analog of curcumin, termed 3, 5-bis (2-flurobenzylidene) piperidin-4-one (EF24), has been reported to inhibit the growth of a variety of cancer cells both in vitro and in vivo. However, whether EF24 has anticancer effects on cholangiocarcinoma (CCA) cells and the mechanisms remain to be investigated. The aim of our study was to evaluate the molecular mechanisms underlying the anticancer effects of EF24 on CCA tumor growth and metastasis. Cell proliferation, apoptosis, migration, invasion, tumorigenesis and metastasis were examined. EF24 exhibited time- and dose-dependent inhibitory effects on HuCCT-1, TFK-1 and HuH28 human CCA cell lines. EF24 inhibited CCA cell proliferation, migration, and induced G2/M phase arrest. EF24 induced cell apoptosis along with negative regulation of NF-κB- X-linked inhibitor of apoptosis protein (XIAP) signaling pathway. XIAP inhibition by lentivirus mediated RNA interference enhanced EF24-induced apoptosis, while XIAP overexpression reduced it in CCA cells. In vivo, EF24 significantly suppressed the growth of CCA tumor xenografts and tumor metastasis while displaying low toxicity levels. Our findings indicate that EF24 is a potent antitumor agent that inhibits tumor growth and metastasis by inhibiting NF-κB dependent signaling pathways. EF24 may represent a novel approach for CCA treatment. PMID:27571770

  5. Metformin inhibits tumor growth by regulating multiple miRNAs in human cholangiocarcinoma.

    PubMed

    Jiang, Xingming; Ma, Ning; Wang, Dayong; Li, Fuyuan; He, Rongzhang; Li, Dongliang; Zhao, Ruiqi; Zhou, Qingxin; Wang, Yimin; Zhang, Fumin; Wan, Ming; Kang, Pengcheng; Gao, Xu; Cui, Yunfu

    2015-02-20

    The antidiabetic drug metformin exerts antineoplastic effects in many types of malignancies, however the effect of metformin on cholangiocarcinoma (CCA) still remains unclear. In the present study, we investigated that metformin treatment was closely associated with the clinicopathologic characteristics and improved postoperative survival of CCA patients. Metformin inhibited CCA tumor growth by cell cycle arrest in vitro and in vivo. We explored that the expression of six miRNAs (mir124, 182, 27b, let7b, 221 and 181a), which could directly target cell-cycle-regulatory genes, was altered by metformin in vitro and in vivo. These miRNAs were dysregulated in cholangiocarcinoma and promoted the CCA genesis and metformin exactly modulated these carcinogenic miRNAs expression to arrest the cell cycle and inhibit the proliferation. Meanwhile, these miRNAs expression changes correlated with the tumor volume and postoperative survival of CCA patients and could be used to predict the prognosis. Further we confirmed that metformin upregulated Drosha to modulate these miRNAs expression. Our results elucidated that metformin inhibited CCA tumor growth via the regulation of Drosha-mediated multiple carcinogenic miRNAs expression and comprehensive evaluation of these miRNAs expression could be more efficient to predict the prognosis. Moreover, metformin might be a quite promising strategy for CCA prevention and treatment. PMID:25605008

  6. NSK-01105, a Novel Sorafenib Derivative, Inhibits Human Prostate Tumor Growth via Suppression of VEGFR2/EGFR-Mediated Angiogenesis

    PubMed Central

    Yu, Pengfei; Ye, Liang; Wang, Hongbo; Du, Guangying; Zhang, Jianzhao; Zuo, Yanhua; Zhang, Jinghai; Tian, Jingwei

    2014-01-01

    The purpose of this study is to investigate the anti-angiogenic activities of NSK-01105, a novel sorafenib derivative, in in vitro, ex vivo and in vivo models, and explore the potential mechanisms. NSK-01105 significantly inhibited vascular endothelial growth factor (VEGF)-induced migration and tube formation of human umbilical vein endothelial cells at non-cytotoxic concentrations as shown by wound-healing, transwell migration and endothelial cell tube formation assays, respectively. Cell viability and invasion of LNCaP and PC-3 cells were significantly inhibited by cytotoxicity assay and matrigel invasion assay. Furthermore, NSK-01105 also inhibited ex vivo angiogenesis in matrigel plug assay. Western blot analysis showed that NSK-01105 down-regulated VEGF-induced phosphorylation of VEGF receptor 2 (VEGFR2) and the activation of epidermal growth factor receptor (EGFR). Tumor volumes were significantly reduced by NSK-01105 at 60 mg/kg/day in both xenograft models. Immunohistochemical staining demonstrated a close association between inhibition of tumor growth and neovascularization. Collectively, our results suggest a role of NSK-01105 in treatment for human prostate tumors, and one of the potential mechanisms may be attributed to anti-angiogenic activities. PMID:25551444

  7. Inhibition of lactate transport in Ehrlich ascites tumor cells and human erythrocytes by a synthetic anhydride of lactic acid.

    PubMed

    Johnson, J H; Belt, J A; Dubinsky, W P; Zimniak, A; Racker, E

    1980-08-01

    The synthesis and some of the physical and biological characteristics of a new inhibitor of lactate transport are described. The inhibitor is isobutylcarbonyl lactayl anhydride (iBCLA). It is formed by the condensation of lactic acid and isobutylchloroformate. It inhibits lactate transport 50% at 0.5 microgram/mg of protein in both Ehrlich ascites tumor cells and human erythrocytes. In contrast, 15 microgram of iBCLA/mg of protein is required for 50% inhibition of phosphate transport in erythrocytes, and phosphate transport in Ehrlich ascites tumor cells is unaffected at levels as high as 50 microgram of iBCLA/mg of protein. A time-dependent and concentration-dependent reversal of lactate transport inhibition took place on exposure of iBCLA-treated Ehrlich ascites cells to hydroxylamine or dithiothreitol. These data, along with the observed sensitivity of the lactate transporter to sulfhydryl reagents [Spencer, T. L., & Lehninger, A. L. (1976) Biochem. J. 154, 405-414], suggest that iBCLA acylates an essential sulfhydryl group on the transporter. When glycolyzing Ehrlich ascites tumor cells were treated with concentrations of iBCLA sufficient for complete inhibition of lactate transport, intracellular lactate levels increased, intracellular pH and extra-cellular lactate levels decreased, and overall lactate production was inhibited. PMID:7407072

  8. Shikonin Inhibits the Proliferation of Human Breast Cancer Cells by Reducing Tumor-Derived Exosomes.

    PubMed

    Wei, Yao; Li, Mingzhen; Cui, Shufang; Wang, Dong; Zhang, Chen-Yu; Zen, Ke; Li, Limin

    2016-01-01

    Shikonin is a naphthoquinone isolated from the traditional Chinese medicine Lithospermum. It has been used in the treatment of various tumors. However, the effects of shikonin on such diseases have not been fully elucidated. In the present study, we detected the exosome release of a breast cancer cell line (MCF-7) with shikonin treatment and found a positive relationship between the level of secreted exosomes and cell proliferation. We next analyzed miRNA profiles in MCF-7 cells and exosomes and found that some miRNAs are specifically sorted and abundant in exosomes. Knockdown of the most abundant miRNAs in exosomes and the MCF-7 proliferation assay showed that miR-128 in exosomes negatively regulates the level of Bax in MCF-7 recipient cells and inhibits cell proliferation. These results show that shikonin inhibits the proliferation of MCF-7 cells through reducing tumor-derived exosomal miR-128. The current study suggests that shikonin suppresses MCF-7 growth by the inhibition of exosome release. PMID:27322220

  9. Salinomycin inhibits proliferation and induces apoptosis of human nasopharyngeal carcinoma cell in vitro and suppresses tumor growth in vivo

    SciTech Connect

    Wu, Danxin; Zhang, Yu; Huang, Jie; Fan, Zirong; Shi, Fengrong; Wang, Senming

    2014-01-10

    Highlight: •We first evaluated the effect of salinomycin on nasopharyngeal carcinoma (NPC). •Salinomycin could inhibit Wnt/β-catenin signaling and induce apoptosis in NPC. •So salinomycin may be a good potential candidate for the chemotherapy of NPC. -- Abstract: Salinomycin (Sal) is a polyether ionophore antibiotic that has recently been shown to induce cell death in various human cancer cells. However, whether salinomycin plays a functional role in nasopharyngeal carcinoma (NPC) has not been determined to date. The present study investigated the chemotherapeutic efficacy of salinomycin and its molecular mechanisms of action in NPC cells. Salinomycin efficiently inhibited proliferation and invasion of 3 NPC cell lines (CNE-1, CNE-2, and CNE-2/DDP) and activated a extensive apoptotic process that is accompanied by activation of caspase-3 and caspase-9, and decreased mitochondrial membrane potential. Meanwhile, the protein expression level of the Wnt coreceptor lipoprotein receptor related protein 6 (LRP6) and β-catenin was down-regulated, which showed that the Wnt/β-catenin signaling was involved in salinomycin-induced apoptosis of NPC cells. In a nude mouse NPC xenograft model, the anti-tumor effect of salinomycin was associated with the downregulation of β-catenin expression. The present study demonstrated that salinomycin can effectively inhibit proliferation and invasion, and induce apoptosis of NPC cells in vitro and inhibit tumor growth in vivo, probably via the inhibition of Wnt/β-catenin signaling, suggesting salinomycin as a potential candidate for the chemotherapy of NPC.

  10. Telomerase antagonists GRN163 and GRN163L inhibit tumor growth and increase chemosensitivity of human hepatoma.

    PubMed

    Djojosubroto, Meta W; Chin, Allison C; Go, Ning; Schaetzlein, Sonja; Manns, Michael P; Gryaznov, Sergei; Harley, Calvin B; Rudolph, K Lenhard

    2005-11-01

    Most cancer cells have an immortal growth capacity as a consequence of telomerase reactivation. Inhibition of this enzyme leads to increased telomere dysfunction, which limits the proliferative capacity of tumor cells; thus, telomerase inhibition represents a potentially safe and universal target for cancer treatment. We evaluated the potential of two thio-phosphoramidate oligonucleotide inhibitors of telomerase, GRN163 and GRN163L, as drug candidates for the treatment of human hepatoma. GRN163 and GRN163L were tested in preclinical studies using systemic administration to treat flank xenografts of different human hepatoma cell lines (Hep3B and Huh7) in nude mice. The studies showed that both GRN163 and GRN163L inhibited telomerase activity and tumor cell growth in a dose-dependent manner in vitro and in vivo. The potency and efficacy of the lipid-conjugated antagonist, GRN163L, was superior to the nonlipidated parent compound, GRN163. Impaired tumor growth in vivo was associated with critical telomere shortening, induction of telomere dysfunction, reduced rate of cell proliferation, and increased apoptosis in the treatment groups. In vitro, GRN163L administration led to higher prevalence of chromosomal telomere-free ends and DNA damage foci in both hepatoma cell lines. In addition, in vitro chemosensitivity assay showed that pretreatment with GRN163L increased doxorubicin sensitivity of Hep3B. In conclusion, our data support the development of GRN163L, a novel lipidated conjugate of the telomerase inhibitor GRN163, for systemic treatment of human hepatoma. In addition to limiting the proliferative capacity of hepatoma, GRN163L might also increase the sensitivity of this tumor type to conventional chemotherapy. PMID:16114043

  11. Tetrandrine inhibits Wnt/β-catenin signaling and suppresses tumor growth of human colorectal cancer.

    PubMed

    He, Bai-Cheng; Gao, Jian-Li; Zhang, Bing-Qiang; Luo, Qing; Shi, Qiong; Kim, Stephanie H; Huang, Enyi; Gao, Yanhong; Yang, Ke; Wagner, Eric R; Wang, Linyuan; Tang, Ni; Luo, Jinyong; Liu, Xing; Li, Mi; Bi, Yang; Shen, Jikun; Luther, Gaurav; Hu, Ning; Zhou, Qixin; Luu, Hue H; Haydon, Rex C; Zhao, Yingming; He, Tong-Chuan

    2011-02-01

    As one of the most common malignancies, colon cancer is initiated by abnormal activation of the Wnt/β-catenin pathway. Although the treatment options have increased for some patients, overall progress has been modest. Thus, there is a great need to develop new treatments. We have found that bisbenzylisoquinoline alkaloid tetrandrine (TET) exhibits anticancer activity. TET is used as a calcium channel blocker to treat hypertensive and arrhythmic conditions in Chinese medicine. Here, we investigate the molecular basis underlying TET's anticancer activity. We compare TET with six chemotherapy drugs in eight cancer lines and find that TET exhibits comparable anticancer activities with camptothecin, vincristine, paclitaxel, and doxorubicin, and better than that of 5-fluorouracil (5-FU) and carboplatin. TET IC₅₀ is ≤5 μM in most of the tested cancer lines. TET exhibits synergistic anticancer activity with 5-FU and reduces migration and invasion capabilities of HCT116 cells. Furthermore, TET induces apoptosis and inhibits xenograft tumor growth of colon cancer. TET treatment leads to a decrease in β-catenin protein level in xenograft tumors, which is confirmed by T-cell factor/lymphocyte enhancer factor and c-Myc reporter assays. It is noteworthy that HCT116 cells with allelic oncogenic β-catenin deleted are less sensitive to TET-mediated inhibition of proliferation, viability, and xenograft tumor growth. Thus, our findings strongly suggest that the anticancer effect of TET in colon cancer may be at least in part mediated by targeting β-catenin activity. Therefore, TET may be used alone or in combination as an effective anticancer agent. PMID:20978119

  12. Let-7a inhibits tumor cell growth and metastasis by directly targeting RTKN in human colon cancer.

    PubMed

    Li, Bin; Chen, Peng; Chang, Yanxiang; Qi, Jingpeng; Fu, Hui; Guo, Huifang

    2016-09-16

    Colorectal cancer (CRC) is the third most common cancer worldwide, with high morbidity. MicroRNAs (miRNAs) are endogenous small RNAs that play important roles in regulating multiple biological and pathologic processes. The differential expression of miRNAs in CRC was first reported in 2003. Accumulated evidence indicates that lethal-7a (let-7a, miRNA) generally functions as a tumor suppressor in several human cancers. However, the role of let-7a in human colon cancer remains unclear. The aim of this study was to investigate the biological functions of let-7a and its potential role in colon cancer. We first discovered that let-7a level was significantly decreased in colon cancer tissues and cell lines (HT-29, HCT-116, LoVo, SW480, and SW620). To explore the effects of let-7a on colon cancer, let-7a over-expressed HCT-116 and SW620 cells were constructed. Further studies demonstrated that over-expressed let-7a could remarkably inhibit HCT-116 and SW620 cell growth and metastasis by directly down-regulating Rhotekin (RTKN). When RTKN was reintroduced into let-7a mimic transfected HCT-116 or SW620 cells, the inhibition effects of let-7a on colon cancer cell growth and metastasis were markedly reversed. In conclusion, our research shows that let-7a can inhibit tumor cell growth and metastasis by directly targeting RTKN in human colon cancer. PMID:27498032

  13. Adipose Tissue–derived Mesenchymal Stem Cells Expressing Prodrug-converting Enzyme Inhibit Human Prostate Tumor Growth

    PubMed Central

    Cavarretta, Ilaria T; Altanerova, Veronika; Matuskova, Miroslava; Kucerova, Lucia; Culig, Zoran; Altaner, Cestmir

    2009-01-01

    The ability of human adipose tissue–derived mesenchymal stem cells (AT-MSCs), engineered to express the suicide gene cytosine deaminase::uracil phosphoribosyltransferase (CD::UPRT), to convert the relatively nontoxic 5-fluorocytosine (5-FC) into the highly toxic antitumor 5-fluorouracil (5-FU) together with their ability to track and engraft into tumors and micrometastases makes these cells an attractive tool to activate prodrugs directly within the tumor mass. In this study, we tested the feasibility and efficacy of these therapeutic cells to function as cellular vehicles of prodrug-activating enzymes in prostate cancer (PC) therapy. In in vitro migration experiments we have shown that therapeutic AT-MSCs migrated to all the prostate cell lines tested. In a pilot preclinical study, we observed that coinjections of human bone metastatic PC cells along with the transduced AT-MSCs into nude mice treated with 5-FC induced a complete tumor regression in a dose dependent manner or did not even allow the establishment of the tumor. More importantly, we also demonstrated that the therapeutic cells were effective in significantly inhibiting PC tumor growth after intravenous administration that is a key requisite for any clinical application of gene-directed enzyme prodrug therapies. PMID:19844197

  14. Effect of celecoxib on inhibiting tumor repopulation during radiotherapy in human FaDu squamous cell carcinoma

    PubMed Central

    Yang, Jia; Liu, Jing; Sun, Xin-Dong; Hu, Xu-Dong; Sun, Ju-Jie; Li, Yu-Hui; Yu, Jin-Ming

    2014-01-01

    Aim of the study FaDu human squamous cell carcinoma (FaDu-hSCC) demonstrated accelerated tumor repopulation during fractionated irradiation with pathological validation in a xenograft model system. Previous studies showed that the selective cyclooxygenase (COX)-2 inhibitor celecoxib can enhance the tumor response to radiotherapy. So we aimed to explore the effect of celecoxib in inducing apoptosis and inhibiting repopulation of FaDu tumors in nude mice during fractionated radiotherapy. Material and methods FaDu-hSCC was transplanted into the right hind leg of BALB/C nude mice. Mice were treated with celecoxib and/or fractionated irradiation. Celecoxib (100 mg/kg/day) was administered by daily gavage. Irradiation was delivered with 12 to 18 fractions of 3.0 Gy daily or every second day based on Petersen's repopulation model. At different time points, tumors were excised for immunohistochemistry staining. Results Significant tumor repopulation occurred after about 18 days of radiotherapy. On average, Ki-67 and bromodeoxyuridine (BrdUrd) labeling indices (LI) decreased with daily irradiation (both p < 0.05) and increased with every-second-day irradiation (both p > 0.05), suggesting accelerated repopulation. Ki-67 LI decreased in celecoxib concurrent with radiotherapy for 12 fractions in 24 days and 18 fractions in 36 days compared with irradiated alone (p = 0.004 and 0.042, respectively). BrdUrd LI values were lower in the concurrent groups than irradiated alone (p = 0.001 and 0.006, respectively). Epithelial growth factor receptor (EGFR) expression score decreased in the concurrent groups than irradiated alone (p = 0.037 and 0.031, respectively). Caspase-3 expression scores were higher in the concurrent groups than irradiated alone (p = 0.05 and 0.006, respectively). Conclusions Celecoxib concurrent radiotherapy could inhibit tumor repopulation and increase tumor apoptosis during the treatment in FaDu squamous cell carcinoma. PMID:25258584

  15. Generation and Characterization of Small Single Domain Antibodies Inhibiting Human Tumor Necrosis Factor Receptor 1*

    PubMed Central

    Steeland, Sophie; Puimège, Leen; Vandenbroucke, Roosmarijn E.; Van Hauwermeiren, Filip; Haustraete, Jurgen; Devoogdt, Nick; Hulpiau, Paco; Leroux-Roels, Geert; Laukens, Debby; Meuleman, Philip; De Vos, Martine; Libert, Claude

    2015-01-01

    The cytokine TNF is a well known drug target for several inflammatory diseases such as Crohn disease. Despite the great success of TNF blockers, therapy could be improved because of high costs and side effects. Selective inhibition of TNF receptor (TNFR) 1 signaling holds the potential to greatly reduce the pro-inflammatory activity of TNF, thereby preserving the advantageous immunomodulatory signals mediated by TNFR2. We generated a selective human TNFR1 inhibitor based on Nanobody (Nb) technology. Two anti-human TNFR1 Nbs were linked with an anti-albumin Nb to generate Nb Alb-70-96 named “TNF Receptor-One Silencer” (TROS). TROS selectively binds and inhibits TNF/TNFR1 and lymphotoxin-α/TNFR1 signaling with good affinity and IC50 values, both of which are in the nanomolar range. Surface plasmon resonance analysis reveals that TROS competes with TNF for binding to human TNFR1. In HEK293T cells, TROS strongly reduces TNF-induced gene expression, like IL8 and TNF, in a dose-dependent manner; and in ex vivo cultured colon biopsies of CD patients, TROS inhibits inflammation. Finally, in liver chimeric humanized mice, TROS antagonizes inflammation in a model of acute TNF-induced liver inflammation, reflected in reduced human IL8 expression in liver and reduced IL6 levels in serum. These results demonstrate the considerable potential of TROS and justify the evaluation of TROS in relevant disease animal models of both acute and chronic inflammation and eventually in patients. PMID:25538244

  16. Triple combination of irradiation, chemotherapy (pemetrexed), and VEGFR inhibition (SU5416) in human endothelial and tumor cells

    SciTech Connect

    Bischof, Marc; Abdollahi, Amir; Gong Ping; Stoffregen, Clemens; Lipson, Kenneth E.; Debus, Juergen; Weber, Klaus J.; Huber, Peter E. . E-mail: p.huber@dkfz.de

    2004-11-15

    Purpose: This is the first preclinical report evaluating a trimodal therapy consisting of irradiation, chemotherapy, and antiangiogenesis in the context of a multimodal anticancer strategy. The combination of the folate antimetabolite pemetrexed, SU5416, a receptor tyrosine kinase inhibitor of VEGFR2, and irradiation was investigated in human endothelial cells and tumor cell lines. Methods and materials: Primary isolated human umbilical vein endothelial cells (HUVEC), human dermal microvascular endothelial cells (HDMEC), and human glioblastoma (U87) and prostate cancer cells (PC3) were exposed to pemetrexed (2 h) alone and in combination with SU5416 (2 h). When combined with irradiation up to 8 Gy, fixed concentrations of pemetrexed (1.06 {mu}M) and SU5416 (1.0 {mu}M) were used. Proliferation and clonogenic assays were conducted with endothelial and tumor cells. The migration/invasion ability of endothelial cells and the ability to produce tubular structures were tested in Matrigel and tube formation assays. Apoptosis was measured by sub-G1 DNA and caspase-3 flow cytometry. To investigate underlying cell signaling, immunocytochemistry was used to detect Akt survival signaling involvement. Results: Triple combination using only a low-toxicity drug exposure of pemetrexed and SU5416 results in greater response than each treatment alone or than each combination of two modalities in all tested endothelial and tumor cell models. Triple combination substantially inhibits proliferation, migration/invasion, tube formation, and clonogenic survival. Triple combination also induced the highest rate of apoptosis in HDMEC and HUVEC as indicated by sub-1 G1 and caspase-3 assessment. Interestingly, triple combination therapy also reduces proliferation and clonogenic survival significantly in U87 and PC3 tumor cell lines. SU5416 potently inhibited Akt phosphorylation which could be induced by radiation and radiochemotherapy in human endothelial cells. Conclusions: Our findings

  17. Wee1 inhibition by MK-1775 leads to tumor inhibition and enhances efficacy of gemcitabine in human sarcomas.

    PubMed

    Kreahling, Jenny M; Foroutan, Parastou; Reed, Damon; Martinez, Gary; Razabdouski, Tiffany; Bui, Marilyn M; Raghavan, Meera; Letson, Douglas; Gillies, Robert J; Altiok, Soner

    2013-01-01

    Sarcomas are rare and heterogeneous mesenchymal tumors affecting both pediatric and adult populations with more than 70 recognized histologies. Doxorubicin and ifosfamide have been the main course of therapy for treatment of sarcomas; however, the response rate to these therapies is about 10-20% in metastatic setting. Toxicity with the drug combination is high, response rates remain low, and improvement in overall survival, especially in the metastatic disease, remains negligible and new agents are needed. Wee1 is a critical component of the G2/M cell cycle checkpoint control and mediates cell cycle arrest by regulating the phosphorylation of CDC2. Inhibition of Wee1 by MK1775 has been reported to enhance the cytotoxic effect of DNA damaging agents in different types of carcinomas. In this study we investigated the therapeutic efficacy of MK1775 in various sarcoma cell lines, patient-derived tumor explants ex vivo and in vivo both alone and in combination with gemcitabine, which is frequently used in the treatment of sarcomas. Our data demonstrate that MK1775 treatment as a single agent at clinically relevant concentrations leads to unscheduled entry into mitosis and initiation of apoptotic cell death in all sarcomas tested. Additionally, MK1775 significantly enhances the cytotoxic effect of gemcitabine in sarcoma cells lines with different p53 mutational status. In patient-derived bone and soft tissue sarcoma samples we showed that MK1775 alone and in combination with gemcitabine causes significant apoptotic cell death. Magnetic resonance imaging (MRI) and histopathologic studies showed that MK1775 induces significant cell death and terminal differentiation in a patient-derived xenograft mouse model of osteosarcoma in vivo. Our results together with the high safety profile of MK1775 strongly suggest that this drug can be used as a potential therapeutic agent in the treatment of both adult as well as pediatric sarcoma patients. PMID:23520471

  18. Wee1 Inhibition by MK-1775 Leads to Tumor Inhibition and Enhances Efficacy of Gemcitabine in Human Sarcomas

    PubMed Central

    Kreahling, Jenny M.; Foroutan, Parastou; Reed, Damon; Martinez, Gary; Razabdouski, Tiffany; Bui, Marilyn M.; Raghavan, Meera; Letson, Douglas; Gillies, Robert J.; Altiok, Soner

    2013-01-01

    Sarcomas are rare and heterogeneous mesenchymal tumors affecting both pediatric and adult populations with more than 70 recognized histologies. Doxorubicin and ifosfamide have been the main course of therapy for treatment of sarcomas; however, the response rate to these therapies is about 10–20% in metastatic setting. Toxicity with the drug combination is high, response rates remain low, and improvement in overall survival, especially in the metastatic disease, remains negligible and new agents are needed. Wee1 is a critical component of the G2/M cell cycle checkpoint control and mediates cell cycle arrest by regulating the phosphorylation of CDC2. Inhibition of Wee1 by MK1775 has been reported to enhance the cytotoxic effect of DNA damaging agents in different types of carcinomas. In this study we investigated the therapeutic efficacy of MK1775 in various sarcoma cell lines, patient-derived tumor explants ex vivo and in vivo both alone and in combination with gemcitabine, which is frequently used in the treatment of sarcomas. Our data demonstrate that MK1775 treatment as a single agent at clinically relevant concentrations leads to unscheduled entry into mitosis and initiation of apoptotic cell death in all sarcomas tested. Additionally, MK1775 significantly enhances the cytotoxic effect of gemcitabine in sarcoma cells lines with different p53 mutational status. In patient-derived bone and soft tissue sarcoma samples we showed that MK1775 alone and in combination with gemcitabine causes significant apoptotic cell death. Magnetic resonance imaging (MRI) and histopathologic studies showed that MK1775 induces significant cell death and terminal differentiation in a patient-derived xenograft mouse model of osteosarcoma in vivo. Our results together with the high safety profile of MK1775 strongly suggest that this drug can be used as a potential therapeutic agent in the treatment of both adult as well as pediatric sarcoma patients. PMID:23520471

  19. Human CAR T cells with cell-intrinsic PD-1 checkpoint blockade resist tumor-mediated inhibition.

    PubMed

    Cherkassky, Leonid; Morello, Aurore; Villena-Vargas, Jonathan; Feng, Yang; Dimitrov, Dimiter S; Jones, David R; Sadelain, Michel; Adusumilli, Prasad S

    2016-08-01

    Following immune attack, solid tumors upregulate coinhibitory ligands that bind to inhibitory receptors on T cells. This adaptive resistance compromises the efficacy of chimeric antigen receptor (CAR) T cell therapies, which redirect T cells to solid tumors. Here, we investigated whether programmed death-1-mediated (PD-1-mediated) T cell exhaustion affects mesothelin-targeted CAR T cells and explored cell-intrinsic strategies to overcome inhibition of CAR T cells. Using an orthotopic mouse model of pleural mesothelioma, we determined that relatively high doses of both CD28- and 4-1BB-based second-generation CAR T cells achieved tumor eradication. CAR-mediated CD28 and 4-1BB costimulation resulted in similar levels of T cell persistence in animals treated with low T cell doses; however, PD-1 upregulation within the tumor microenvironment inhibited T cell function. At lower doses, 4-1BB CAR T cells retained their cytotoxic and cytokine secretion functions longer than CD28 CAR T cells. The prolonged function of 4-1BB CAR T cells correlated with improved survival. PD-1/PD-1 ligand [PD-L1] pathway interference, through PD-1 antibody checkpoint blockade, cell-intrinsic PD-1 shRNA blockade, or a PD-1 dominant negative receptor, restored the effector function of CD28 CAR T cells. These findings provide mechanistic insights into human CAR T cell exhaustion in solid tumors and suggest that PD-1/PD-L1 blockade may be an effective strategy for improving the potency of CAR T cell therapies. PMID:27454297

  20. An easily accessible sulfated saccharide mimetic inhibits in vitro human tumor cell adhesion and angiogenesis of vascular endothelial cells

    PubMed Central

    Marano, Grazia; Gronewold, Claas; Frank, Martin; Merling, Anette; Kliem, Christian; Sauer, Sandra; Wiessler, Manfred; Frei, Eva

    2012-01-01

    Summary Oligosaccharides aberrantly expressed on tumor cells influence processes such as cell adhesion and modulation of the cell’s microenvironment resulting in an increased malignancy. Schmidt’s imidate strategy offers an effective method to synthesize libraries of various oligosaccharide mimetics. With the aim to perturb interactions of tumor cells with extracellular matrix proteins and host cells, molecules with 3,4-bis(hydroxymethyl)furan as core structure were synthesized and screened in biological assays for their abilities to interfere in cell adhesion and other steps of the metastatic cascade, such as tumor-induced angiogenesis. The most active compound, (4-{[(β-D-galactopyranosyl)oxy]methyl}furan-3-yl)methyl hydrogen sulfate (GSF), inhibited the activation of matrix-metalloproteinase-2 (MMP-2) as well as migration of the human melanoma cells of the lines WM-115 and WM-266-4 in a two-dimensional migration assay. GSF inhibited completely the adhesion of WM-115 cells to the extracellular matrix (ECM) proteins, fibrinogen and fibronectin. In an in vitro angiogenesis assay with human endothelial cells, GSF very effectively inhibited endothelial tubule formation and sprouting of blood vessels, as well as the adhesion of endothelial cells to ECM proteins. GSF was not cytotoxic at biologically active concentrations; neither were 3,4-bis{[(β-D-galactopyranosyl)oxy]methyl}furan (BGF) nor methyl β-D-galactopyranoside nor 3,4-bis(hydroxymethyl)furan, which were used as controls, eliciting comparable biological activity. In silico modeling experiments, in which binding of GSF to the extracellular domain of the integrin αvβ3 was determined, revealed specific docking of GSF to the same binding site as the natural peptidic ligands of this integrin. The sulfate in the molecule coordinated with one manganese ion in the binding site. These studies show that this chemically easily accessible molecule GSF, synthesized in three steps from 3,4-bis

  1. Frondoside A inhibits human breast cancer cell survival, migration, invasion and the growth of breast tumor xenografts.

    PubMed

    Al Marzouqi, Nadia; Iratni, Rabah; Nemmar, Abderrahim; Arafat, Kholoud; Ahmed Al Sultan, Mahmood; Yasin, Javed; Collin, Peter; Mester, Jan; Adrian, Thomas E; Attoub, Samir

    2011-10-01

    Breast cancer is a major challenge for pharmacologists to develop new drugs to improve the survival of cancer patients. Frondoside A is a triterpenoid glycoside isolated from the sea cucumber, Cucumaria frondosa. It has been demonstrated that Frondoside A inhibited the growth of pancreatic cancer cells in vitro and in vivo. We investigated the impact of Frondoside A on human breast cancer cell survival, migration and invasion in vitro, and on tumor growth in nude mice, using the human estrogen receptor-negative breast cancer cell line MDA-MB-231. The non-tumorigenic MCF10-A cell line derived from normal human mammary epithelium was used as control. Frondoside A (0.01-5 μM) decreased the viability of breast cancer cells in a concentration- and time-dependent manner, with 50%-effective concentration (EC50) of 2.5 μM at 24h. MCF10-A cells were more resistant to the cytotoxic effect of Frondoside A (EC50 superior to 5 μM at 24 h). In the MDA-MB-231 cells, Frondoside A effectively increased the sub-G1 (apoptotic) cell fraction through the activation of p53, and subsequently the caspases 9 and 3/7 cell death pathways. In addition, Frondoside A induced a concentration-dependent inhibition of MDA-MB-231 cell migration and invasion. In vivo, Frondoside A (100 μg/kg/dayi.p. for 24 days) strongly decreased the growth of MDA-MB-231 tumor xenografts in athymic mice, without manifest toxic side-effects. Moreover, we found that Frondoside A could enhance the killing of breast cancer cells induced by the chemotherapeutic agent paclitaxel. These findings identify Frondoside A as a promising novel therapeutic agent for breast cancer. PMID:21741966

  2. Inhibition of Autophagy Enhances Curcumin United light irradiation-induced Oxidative Stress and Tumor Growth Suppression in Human Melanoma Cells.

    PubMed

    Niu, Tianhui; Tian, Yan; Mei, Zhusong; Guo, Guangjin

    2016-01-01

    Malignant melanoma is the most aggressive form of skin carcinoma, which possesses fast propagating and highly invasive characteristics. Curcumin is a natural phenol compound that has various biological activities, such as anti-proliferative and apoptosis-accelerating impacts on tumor cells. Unfortunately, the therapeutical activities of Cur are severely hindered due to its extremely low bioavailability. In this study, a cooperative therapy of low concentration Cur combined with red united blue light irradiation was performed to inspect the synergistic effects on the apoptosis, proliferation and autophagy in human melanoma A375 cell. The results showed that red united blue light irradiation efficaciously synergized with Cur to trigger oxidative stress-mediated cell death, induce apoptosis and inhibit cell proliferation. Meanwhile, Western blotting revealed that combined disposure induced the formation of autophagosomes. Conversely, inhibition of the autophagy enhanced apoptosis, obstructed cell cycle arrest and induced reversible proliferation arrest to senescence. These findings suggest that Cur combined with red united blue light irradiation could generate photochemo-preventive effects via enhancing apoptosis and triggering autophagy, and pharmacological inhibition of autophagy convert reversible arrested cells to senescence, therefore reducing the possibility that damaged cells might escape programmed death. PMID:27502897

  3. Inhibition of Autophagy Enhances Curcumin United light irradiation-induced Oxidative Stress and Tumor Growth Suppression in Human Melanoma Cells

    PubMed Central

    Niu, Tianhui; Tian, Yan; Mei, Zhusong; Guo, Guangjin

    2016-01-01

    Malignant melanoma is the most aggressive form of skin carcinoma, which possesses fast propagating and highly invasive characteristics. Curcumin is a natural phenol compound that has various biological activities, such as anti-proliferative and apoptosis-accelerating impacts on tumor cells. Unfortunately, the therapeutical activities of Cur are severely hindered due to its extremely low bioavailability. In this study, a cooperative therapy of low concentration Cur combined with red united blue light irradiation was performed to inspect the synergistic effects on the apoptosis, proliferation and autophagy in human melanoma A375 cell. The results showed that red united blue light irradiation efficaciously synergized with Cur to trigger oxidative stress-mediated cell death, induce apoptosis and inhibit cell proliferation. Meanwhile, Western blotting revealed that combined disposure induced the formation of autophagosomes. Conversely, inhibition of the autophagy enhanced apoptosis, obstructed cell cycle arrest and induced reversible proliferation arrest to senescence. These findings suggest that Cur combined with red united blue light irradiation could generate photochemo-preventive effects via enhancing apoptosis and triggering autophagy, and pharmacological inhibition of autophagy convert reversible arrested cells to senescence, therefore reducing the possibility that damaged cells might escape programmed death. PMID:27502897

  4. Melatonin reversed tumor necrosis factor-alpha-inhibited osteogenesis of human mesenchymal stem cells by stabilizing SMAD1 protein.

    PubMed

    Lian, Chengjie; Wu, Zizhao; Gao, Bo; Peng, Yan; Liang, Anjing; Xu, Caixia; Liu, Lei; Qiu, Xianjian; Huang, Junjun; Zhou, Hang; Cai, Yifeng; Su, Peiqiang; Huang, Dongsheng

    2016-10-01

    Tumor necrosis factor-alpha (TNFα) plays a pivotal role in inflammation-related osteoporosis through the promotion of bone resorption and suppression of bone formation. Numerous drugs have been produced to treat osteoporosis by inhibiting bone resorption, but they offer few benefits to bone formation, which is what is needed by patients with severe bone loss. Melatonin, which can exert both anti-inflammatory and pro-osteogenic effects, shows promise in overcoming TNFα-inhibited osteogenesis and deserves further research. This study demonstrated that melatonin rescued TNFα-inhibited osteogenesis of human mesenchymal stem cells and that the interactions between SMURF1 and SMAD1 mediated the crosstalk between melatonin signaling and TNFα signaling. Additionally, melatonin treatment was found to downregulate TNFα-induced SMURF1 expression and then decrease SMURF1-mediated ubiquitination and degradation of SMAD1 protein, leading to steady bone morphogenetic protein-SMAD1 signaling activity and restoration of TNFα-impaired osteogenesis. Thus, melatonin has prospects for treating osteoporosis caused by inflammatory factors due to its multifaceted functions on regulation of bone formation, bone resorption, and inflammation. Further studies will focus on unveiling the specific mechanisms by which melatonin downregulates SMURF1 expression and confirming the clinical therapeutic value of melatonin in the prevention and therapy of bone loss associated with inflammation. PMID:27265199

  5. Metformin in combination with 5-fluorouracil suppresses tumor growth by inhibiting the Warburg effect in human oral squamous cell carcinoma.

    PubMed

    Harada, Koji; Ferdous, Tarannum; Harada, Toyoko; Ueyama, Yoshiya

    2016-07-01

    Cancer cells show enhanced glucose consumption and lactate production even in the presence of abundant oxygen, a phenomenon known as the Warburg effect, which is related to tumor proliferation, progression and drug-resistance in cancers. Hypoxia-inducible factor-1 (HIF-1) and several members of Phosphatidylinositol-4, 5-bisphosphate 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway positively contribute to the Warburg effect, whereas AMP activated protein Kinase (AMPK) acts as a negative regulator. Targeting the regulator molecules of Warburg effect might be a useful strategy to effectively kill cancer cells. Metformin was reported to be effective against various cancers as it inhibits cell proliferation by activating AMPK, and inhibiting mTOR and HIF-1α. Several studies suggested the efficacy of metformin with 5-fluorouracil (5-FU) against esophageal and colon cancer. In this study, we evaluated the efficacy of metformin and 5-FU combined therapy against human oral squamous cell carcinoma (OSCC) in vitro and in vivo. MTT assay and TUNEL assay revealed that metformin (4 mg/ml) and 5-FU (2.5 µg/ml) combination treatment effectively inhibited cell growth and induced apoptosis in OSCC cell lines (HSC2, HSC3 and HSC4) compared to either agent alone. Lactate colorimetric assay detected decreased level of lactate in the supernatants of metformin and 5-FU treated cells compared to cells treated with metformin or 5-FU. Western blot analysis showed marked downregulation of HIF-1α and mTOR expression, and upregulation of AMPKα in cells treated with metformin and 5-FU combination treatment. Combination therapy with metformin (200 mg/kg, i.p.) and 5-FU (10 mg/kg, i.p.) for 4 weeks (5 days/week) effectively reduced HSC2 tumor growth (77.6%) compared to metformin (59.9%) or 5-FU (52%) alone in nude mice. These findings suggest that metformin and 5-FU combined therapy could exert strong antitumor effect against OSCC through the inhibition of

  6. Characterization of p21Ras-mediated apoptosis induced by protein kinase C inhibition and application to human tumor cell lines.

    PubMed

    Liou, James S; Chen, James S; Faller, Douglas V

    2004-02-01

    Suppression of PKC activity can selectively induce apoptosis in cells expressing a constitutively activated p21Ras protein. We demonstrate that continued expression of p21Ras activity is required in PKC-mediated apoptosis because farnesyltransferase inhibitors abrogated the loss of viability in p21Ras-transformed cells occurring following PKC inhibition. Studies utilizing gene transfer or viral vectors demonstrate that transient expression of oncogenic p21Ras activity is sufficient for induction of apoptosis by PKC inhibition, whereas physiologic activation of p21Ras by growth factor is not sufficient to induce apoptosis. Mechanistically, the p21Ras-mediated apoptosis induced by PKC inhibition is dependent upon mitochondrial dysregulation, with a concurrent loss of mitochondrial membrane potential (psim). Cyclosporine A, which prevented the loss of psim, also inhibited HMG-induced DNA fragmentation in cells expressing an activated p21Ras. Induction of apoptosis by PKC inhibition in human tumors with oncogenic p21Ras mutations was demonstrated. Inhibition of PKC caused increased apoptosis in MIA-PaCa-2, a human pancreatic tumor line containing a mutated Ki-ras allele, when compared to HS766T, a human pancreatic tumor line with normal Ki-ras alleles. Furthermore, PKC inhibition induced apoptosis in HCT116, a human colorectal tumor line containing an oncogenic Ki-ras allele but not in a subline (Hke3) in which the mutated Ki-ras allele had been disrupted. The PKC inhibitor 1-O-hexadecyl-2-O-methyl-rac-glycerol (HMG), significantly reduced p21Ras-mediated tumor growth in vivo in a nude mouse MIA-PaCa-2 xenograft model. Collectively these studies suggest the therapeutic feasibility of targeting PKC activity in tumors expressing an activated p21Ras oncoprotein. PMID:14603530

  7. Preclinical Evidence of Anti-Tumor Activity Induced by EZH2 Inhibition in Human Models of Synovial Sarcoma.

    PubMed

    Kawano, Satoshi; Grassian, Alexandra R; Tsuda, Masumi; Knutson, Sarah K; Warholic, Natalie M; Kuznetsov, Galina; Xu, Shanqin; Xiao, Yonghong; Pollock, Roy M; Smith, Jesse S; Kuntz, Kevin K; Ribich, Scott; Minoshima, Yukinori; Matsui, Junji; Copeland, Robert A; Tanaka, Shinya; Keilhack, Heike

    2016-01-01

    The catalytic activities of covalent and ATP-dependent chromatin remodeling are central to regulating the conformational state of chromatin and the resultant transcriptional output. The enzymes that catalyze these activities are often contained within multiprotein complexes in nature. Two such multiprotein complexes, the polycomb repressive complex 2 (PRC2) methyltransferase and the SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeler have been reported to act in opposition to each other during development and homeostasis. An imbalance in their activities induced by mutations/deletions in complex members (e.g. SMARCB1) has been suggested to be a pathogenic mechanism in certain human cancers. Here we show that preclinical models of synovial sarcoma-a cancer characterized by functional SMARCB1 loss via its displacement from the SWI/SNF complex through the pathognomonic SS18-SSX fusion protein-display sensitivity to pharmacologic inhibition of EZH2, the catalytic subunit of PRC2. Treatment with tazemetostat, a clinical-stage, selective and orally bioavailable small-molecule inhibitor of EZH2 enzymatic activity reverses a subset of synovial sarcoma gene expression and results in concentration-dependent cell growth inhibition and cell death specifically in SS18-SSX fusion-positive cells in vitro. Treatment of mice bearing either a cell line or two patient-derived xenograft models of synovial sarcoma leads to dose-dependent tumor growth inhibition with correlative inhibition of trimethylation levels of the EZH2-specific substrate, lysine 27 on histone H3. These data demonstrate a dependency of SS18-SSX-positive, SMARCB1-deficient synovial sarcomas on EZH2 enzymatic activity and suggests the potential utility of EZH2-targeted drugs in these genetically defined cancers. PMID:27391784

  8. Preclinical Evidence of Anti-Tumor Activity Induced by EZH2 Inhibition in Human Models of Synovial Sarcoma

    PubMed Central

    Tsuda, Masumi; Knutson, Sarah K.; Warholic, Natalie M.; Kuznetsov, Galina; Xu, Shanqin; Xiao, Yonghong; Pollock, Roy M.; Smith, Jesse S.; Kuntz, Kevin K.; Ribich, Scott; Minoshima, Yukinori; Matsui, Junji; Copeland, Robert A.; Tanaka, Shinya; Keilhack, Heike

    2016-01-01

    The catalytic activities of covalent and ATP-dependent chromatin remodeling are central to regulating the conformational state of chromatin and the resultant transcriptional output. The enzymes that catalyze these activities are often contained within multiprotein complexes in nature. Two such multiprotein complexes, the polycomb repressive complex 2 (PRC2) methyltransferase and the SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeler have been reported to act in opposition to each other during development and homeostasis. An imbalance in their activities induced by mutations/deletions in complex members (e.g. SMARCB1) has been suggested to be a pathogenic mechanism in certain human cancers. Here we show that preclinical models of synovial sarcoma—a cancer characterized by functional SMARCB1 loss via its displacement from the SWI/SNF complex through the pathognomonic SS18-SSX fusion protein—display sensitivity to pharmacologic inhibition of EZH2, the catalytic subunit of PRC2. Treatment with tazemetostat, a clinical-stage, selective and orally bioavailable small-molecule inhibitor of EZH2 enzymatic activity reverses a subset of synovial sarcoma gene expression and results in concentration-dependent cell growth inhibition and cell death specifically in SS18-SSX fusion-positive cells in vitro. Treatment of mice bearing either a cell line or two patient-derived xenograft models of synovial sarcoma leads to dose-dependent tumor growth inhibition with correlative inhibition of trimethylation levels of the EZH2-specific substrate, lysine 27 on histone H3. These data demonstrate a dependency of SS18-SSX-positive, SMARCB1-deficient synovial sarcomas on EZH2 enzymatic activity and suggests the potential utility of EZH2-targeted drugs in these genetically defined cancers. PMID:27391784

  9. Biosynthesized Platinum Nanoparticles Inhibit the Proliferation of Human Lung-Cancer Cells in vitro and Delay the Growth of a Human Lung-Tumor Xenograft in vivo

    PubMed Central

    Yogesh, Bendale; Vineeta, Bendale; Rammesh, Natu; Saili, Paul

    2016-01-01

    Objectives: Lung cancer remains a deadly disease with unsatisfactory overall survival. Cisplatin, a standard platinum (Pt)-based chemotherapeutic agent, has the potential to inhibit the growth of lung cancer. Its use, however, is occasionally limited by severe organ toxicity. However, until now, no systematic study has been conducted to verify its efficacy with proper experimental support in vivo. Therefore, we examined whether biosynthesized Pt nanoparticles (NPs) inhibited human lung cancer in vitro and in vivo to validate their use in alternative and complementary medicine. Methods: We evaluated the in vitro and the in vivo anticancer efficiencies of biosynthesized Pt NPs in a subcutaneous xenograft model with A549 cells. Severe combined immune deficient mice (SCID) were divided into four groups: group 1 being the vehicle control group and groups 2, 3 and 4 being the experimental groups. Once the tumor volume had reached 70 ─ 75 mm3, the progression profile of the tumor growth kinetics and the body weights of the mice were measured every week for 6 weeks after oral administration of Pt NPs. Doses of Pt NPs of 500, 1,000 and 2,000 mg/kg of body weight were administered to the experimental groups and a dose of honey was administered to the vehicle control group. The efficacy was quantified by using the delay in tumor growth following the administration of Pt NPs of A549 human-lung-cancer xenografts growing in SCID mice. Results: The in vitro cytotoxicity evaluation indicated that Pt NPs, in a dose-dependent manner, inhibited the growth of A549 cells, and the in vivo evaluation showed that Pt NPs at the mid and high doses effectively inhibited and delayed the growth of lung cancer in SCID mice. Conclusion: These findings confirm the antitumor properties of biosynthesized Pt NPs and suggest that they may be a cost-effective alternative for the treatment of patients with lung cancer. PMID:27386144

  10. Meloxicam combined with sorafenib synergistically inhibits tumor growth of human hepatocellular carcinoma cells via ER stress-related apoptosis.

    PubMed

    Zhong, Jingtao; Xiu, Peng; Dong, Xiaofeng; Wang, Fuhai; Wei, Honglong; Wang, Xin; Xu, Zongzhen; Liu, Feng; Li, Tao; Wang, Yong; Li, Jie

    2015-10-01

    Sorafenib (SOR) is a promising treatment for advanced hepatocellular carcinoma (HCC). However, the precise mechanisms of toxicity and drug resistance have not been fully explored and new strategies are urgently needed for HCC therapy. Meloxicam (MEL) is a selective cyclooxygenase-2 (COX-2) inhibitor which elicits antitumor effects in human HCC cells. In the present study, we investigated the interaction between MEL and SOR in human SMMC‑7721 cells and the role endoplasmic reticulum (ER) stress exerts in the combination of SOR with MEL treatment-induced cytotoxicity. Our results revealed that the combination treatment synergistically inhibited cell proliferation and enhanced apoptosis. Furthermore, the combination treatment enhanced ER stress-related molecules which involved in SMMC-7721 cell apoptosis. GRP78 knockdown by siRNA or co-treatment with MG132 significantly increased this combination treatment-induced apoptosis. In addition, we found that the combination treatment suppressed tumor growth by way of activation of ER stress in in vivo models. We concluded that the combination of SOR with MEL treatment-induced ER stress, and eventually apoptosis in human SMMC-7721 cells. Knockdown of GRP78 using siRNA or proteosome inhibitor enhanced the cytotoxicity of the combination of SOR with MEL-treatment in SMMC-7721 cells. These findings provided a new potential treatment strategy against HCC. PMID:26252057

  11. Human Neural Stem Cells Overexpressing a Carboxylesterase Inhibit Bladder Tumor Growth.

    PubMed

    Choi, Sung S; Chi, Byung Hoon; Chang, In Ho; Kim, Kyung Do; Lee, Sang-Rae; Kim, Seung U; Lee, Hong J

    2016-06-01

    Bladder cancer is a significant clinical and economic problem. Despite intravesical chemotherapy and immunotherapy, up to 80% of patients with non-muscle-invasive bladder cancer develop recurrent tumors, of which 20% to 30% evolve into more aggressive, potentially lethal tumors. Recently, bladder cancer cells are considered to be mediators of resistance to current therapies and therefore represent strong candidates as biologic targets. No effective chemotherapy has yet been developed for advanced bladder cancer. It is desirable that a drug can be delivered directly and specifically to bladder cancer cells. Stem cells have selective migration ability toward cancer cells, and therapeutic genes can be easily transduced into stem cells. In suicide gene therapy for cancer, stem cells carry a gene encoding a carboxylesterase (CE) enzyme that transforms an inert CPT-11 prodrug into a toxic SN-38 product, a topoisomerase 1 inhibitor. In immunodeficient mice, systemically transplanted HB1.F3.CE stem cells migrated toward the tumor implanted by the TCCSUP bladder cancer cell line, and, in combination with CPT-11, the volume of tumors was significantly reduced. These findings may contribute to the development of a new selective chemotherapeutic strategy against bladder cancer. Mol Cancer Ther; 15(6); 1201-7. ©2016 AACR. PMID:27009215

  12. Suppression of homologous recombination sensitizes human tumor cells to IGF-1R inhibition.

    PubMed

    Lodhia, Kunal A; Gao, Shan; Aleksic, Tamara; Esashi, Fumiko; Macaulay, Valentine M

    2015-06-15

    Inhibition of type 1 IGF receptor (IGF-1R) sensitizes to DNA-damaging cancer treatments, and delays repair of DNA double strand breaks (DSBs) by non-homologous end-joining and homologous recombination (HR). In a recent screen for mediators of resistance to IGF-1R inhibitor AZ12253801, we identified RAD51, required for the strand invasion step of HR. These findings prompted us to test the hypothesis that IGF-1R-inhibited cells accumulate DSBs formed at endogenous DNA lesions, and depend on residual HR for their repair. Indeed, initial experiments showed time-dependent accumulation of γH2AX foci in IGF-1R -inhibited or -depleted prostate cancer cells. We then tested effects of suppressing HR, and found that RAD51 depletion enhanced AZ12253801 sensitivity in PTEN wild-type prostate cancer cells but not in cells lacking functional PTEN. Similar sensitization was induced in prostate cancer cells by depletion of BRCA2, required for RAD51 loading onto DNA, and in BRCA2(-/-) colorectal cancer cells, compared with isogenic BRCA2(+/-) cells. We also assessed chemical HR inhibitors, finding that RAD51 inhibitor BO2 blocked RAD51 focus formation and sensitized to AZ12253801. Finally, we tested CDK1 inhibitor RO-3306, which impairs HR by inhibiting CDK1-mediated BRCA1 phosphorylation. R0-3306 suppressed RAD51 focus formation consistent with HR attenuation, and sensitized prostate cancer cells to IGF-1R inhibition, with 2.4-fold reduction in AZ12253801 GI50 and 13-fold reduction in GI80. These data suggest that responses to IGF-1R inhibition are enhanced by genetic and chemical approaches to suppress HR, defining a population of cancers (PTEN wild-type, BRCA mutant) that may be intrinsically sensitive to IGF-1R inhibitory drugs. PMID:25388513

  13. Inhibition of human esophageal squamous cell carcinomas by targeted silencing of tumor enhancer genes: an overview

    PubMed Central

    Islamian, Jalil Pirayesh; Mohammadi, Mohsen; Baradaran, Behzad

    2014-01-01

    Esophageal cancer has been reported as the ninth most common malignancy and ranks as the sixth most frequent cause of death worldwide. Esophageal cancer treatment involves surgery, chemotherapy, radiation therapy, or combination therapy. Novel strategies are needed to boost the oncologic outcome. Recent advances in the molecular biology of esophageal cancer have documented the role of genetic alterations in tumorigenesis. Oncogenes serve a pivotal function in tumorigenesis. Targeted therapies are directed at the unique molecular signature of cancer cells for enhanced efficacy with low toxicity. RNA interference (RNAi) technology is a powerful tool for silencing endogenous or exogenous genes in mammalian cells. Related results have shown that targeting oncogenes with siRNAs, specifically the mRNA, effectively reduces tumor cell proliferation and induces apoptotic cell death. This article will briefly review studies on silencing tumor enhancer genes related to the induction of esophageal cancer. PMID:25009749

  14. Total Alkaloids of Sophora alopecuroides Inhibit Growth and Induce Apoptosis in Human Cervical Tumor HeLa Cells In vitro

    PubMed Central

    Li, Jian-Guang; Yang, Xiao-Yi; Huang, Wei

    2016-01-01

    Background: Uygur females of Xinjiang have the higher incidence of cervical tumor in the country. Alkaloids are the major active ingredients in Sophora alopecuroides, and its antitumor effect was recognized by the medical profession. Xinjiang is the main site of S. alopecuroides production in China so these plants are abundant in the region. Studies on the antitumor properties of total alkaloids of S. alopecuroides (TASA) can take full use of the traditional folk medicine in antitumor unique utility. Objectives: To explore the effects of TASA on proliferation and apoptosis of human cervical tumor HeLa cells in vitro. Materials and Methods: TASA was extracted, purified, and each monomer component was analyzed by high-performance liquid chromatography. The effect of TASA at different concentrations on the survival of HeLa cells was determined after 24 h using the Cell Counting Kit-8. In addition, cells were photographed using an inverted microscope to document morphological changes. The effect of TASA on apoptotic rate of HeLa cells was assessed by flow cytometry. Results: Monomers of TASA were found to be sophoridine, matrine, and sophocarpine. On treatment with 8.75 mg/ml of TASA, more than 50% of HeLa cells died, and cell death rate increased further with longer incubation. The apoptotic rates of HeLa cells in the experimental groups were 16.0% and 33.3% at concentrations of 6.25 mg/ml and 12.50 mg/ml, respectively. Conclusion: TASA can induce apoptosis in cervical tumor HeLa cells, and it has obvious inhibitory effects on cell growth. SUMMARY Total alkaloids of Sophora alopecuroides (TASA) exhibits anti-human cervical tumor propertiesMonomer component of TASA was analyzed by high-performance liquid chromatography, and its main effect component are sophoridine, matrine, and sophocarpineTASA inhibits growth and induces apoptosis in HeLa cells. Abbreviations used: TASA: Total alkaloids of S. alopecuroides, CCK-8: Cell Counting Kit-8, FBS: Fetal bovine serum, PBS

  15. Petiveria alliacea extracts uses multiple mechanisms to inhibit growth of human and mouse tumoral cells

    PubMed Central

    Urueña, Claudia; Cifuentes, Claudia; Castañeda, Diana; Arango, Amparo; Kaur, Punit; Asea, Alexzander; Fiorentino, Susana

    2008-01-01

    Background There is ethnopharmacological evidence that Petiveria alliacea can have antitumor activity; however, the mechanism of its cytotoxic activity is not well understood. We assessed multiple in vitro biological activities of an ethyl acetate soluble plant fraction over several tumor cell lines. Methods Tumor cell lines were evaluated using the following tests: trypan blue exclusion test, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide], flow cytometry, cytoskeleton organization analysis, cell cycle, mitochondria membrane depolarization, clonogenicity test, DNA fragmentation test and differential protein expression by HPLC-Chip/MS analysis. F4 fraction characterization was made by HPLC-MS. Results Petiveria alliacea fraction characterized by de-replication was found to alter actin cytoskeleton organization, induce G2 cell cycle arrest and cause apoptotic cell death in a mitochondria independent way. In addition, we found down regulation of cytoskeleton, chaperone, signal transduction proteins, and proteins involved in metabolic pathways. Finally up regulation of proteins involved in translation and intracellular degradation was also observed. Conclusion The results of this study indicate that Petiveria alliacea exerts multiple biological activities in vitro consistent with cytotoxicity. Further studies in animal models are needed but Petiveria alliacea appears to be a good candidate to be used as an antitumor agent. PMID:19017389

  16. Escin, a Pentacyclic Triterpene, Chemosensitizes Human Tumor Cells through Inhibition of Nuclear Factor-κB Signaling Pathway

    PubMed Central

    Harikumar, Kuzhuvelil B.; Sung, Bokyung; Pandey, Manoj K.; Guha, Sushovan; Krishnan, Sunil

    2010-01-01

    Agents that can enhance tumor cell apoptosis and inhibit invasion have potential for the treatment of cancer. Here, we report the identification of escin, a pentacyclic triterpenoid from horse chestnut that exhibits antitumor potential against leukemia and multiple myeloma. Whether examined by esterase staining, phosphatidyl-serine staining, DNA breakage, or caspase-mediated poly(ADP-ribose) polymerase cleavage, escin potentiated tumor necrosis factor (TNF)-induced apoptosis but inhibited tumor cell invasion. This correlated with the down-regulation of bcl-2, cellular inhibitor of apoptosis protein-2, cyclin D1, cyclooxygenase-2, intercellular adhesion molecule-1, matrix metalloproteinase-9, and vascular endothelial growth factor, which are all regulated by the activation of the transcription factor NF-κB. When examined by electrophoretic mobility shift assay, the triterpenoid suppressed nuclear factor-κB (NF-κB) activation induced by TNF and other inflammatory agents, and this correlated with the inhibition of IκBα phosphorylation and degradation, inhibition of IκB kinase complex (IKK) activation, suppression of p65 phosphorylation and nuclear translocation, and abrogation of NF-κB-dependent reporter activity. Overall, our results demonstrate that escin inhibits activation of NF-κB through inhibition of IKK, leading to down-regulation of NF-κB-regulated cell survival and metastatic gene products and thus resulting in sensitization of cells to cytokines and chemotherapeutic agents. PMID:20103608

  17. Pyrogallol induces G2-M arrest in human lung cancer cells and inhibits tumor growth in an animal model.

    PubMed

    Yang, Chih-Jen; Wang, Chuan-Sheng; Hung, Jen-Yu; Huang, Hurng-Wern; Chia, Yi-Chen; Wang, Pei-Hui; Weng, Ching-Feng; Huang, Ming-Shyan

    2009-11-01

    Pyrogallol, a catechin compound, is an active component of Emblica officinalis extracts and has an anti-proliferative effect on some human cancer cell lines. In our preliminary study, pyrogallol had highly cytotoxic effect on human lung cancer cell lines and less effect on human bronchial epithelium cell line. This study was performed to investigate the beneficial effect of pyrogallol on human lung cancer cell lines - H441 (lung adenocarcinoma) and H520 (lung squamous cell carcinoma). The MTT (cytotoxic) data showed the inhibition growth of lung cancer cells followed pyrogallol treatment. The cell cycle of lung cancer cells was arrested in G2/M phase using flow cytometry. Using Western blot analysis, the cell cycle related proteins - cyclin B1 and Cdc25c were decreased in a time-dependent manner and the phosphorylated Cdc2 (Thr14) was increased within 4h pyrogallol treatment. Moreover, the higher cleavage of poly (ADP)-ribose polymerase (PARP), the increased of Bax concurrent with the decreased of Bcl-2 indicated that pyrogallol treatment resulted in apoptosis of lung cancer cells. The cell apoptosis was also directly demonstrated using Annexin V-FITC and TUNEL stain. Additionally, the tumoricidal effect of pyrogallol was measured using a xenograft nude mice model. After 5 weeks of pyrogallol treatment could cause the regression of tumor. Taken in vitro and in vivo studies together, these results suggest that pyrogallol can be developed as a promising anti-lung cancer drug particular for the non-small cell lung cancer (NSCLC). PMID:19233505

  18. Anti-EphA2 antibodies decrease EphA2 protein levels in murine CT26 colorectal and human MDA-231 breast tumors but do not inhibit tumor growth.

    PubMed

    Kiewlich, David; Zhang, Jianhuan; Gross, Cynthia; Xia, Wei; Larsen, Brent; Cobb, Ronald R; Biroc, Sandra; Gu, Jian-Ming; Sato, Takashi; Light, David R; Heitner, Tara; Willuda, Joerg; Vogel, David; Monteclaro, Felipe; Citkowicz, Andrzej; Roffler, Steve R; Zajchowski, Deborah A

    2006-01-01

    The EphA2 receptor tyrosine kinase has been shown to be over-expressed in cancer and a monoclonal antibody (mAb) that activates and down-modulates EphA2 was reported to inhibit the growth of human breast and lung tumor xenografts in nude mice. Reduction of EphA2 levels by treatment with anti-EphA2 siRNA also inhibited tumor growth, suggesting that the anti-tumor effects of these agents are mediated by decreasing the levels of EphA2. As these studies employed human tumor xenograft models in nude mice with reagents whose cross reactivity with murine EphA2 is unknown, we generated a mAb (Ab20) that preferentially binds, activates, and induces the degradation of murine EphA2. Treatment of established murine CT26 colorectal tumors with Ab20 reduced EphA2 protein levels to approximately 12% of control tumor levels, yet had no effect on tumor growth. CT26 tumor cell colonization of the lung was also not affected by Ab20 administration despite having barely detectable levels of EphA2. We also generated and tested a potent agonistic mAb against human EphA2 (1G9-H7). No inhibition of humanMDA-231 breast tumor xenograft growth was observed despite evidence for >85% reduction of EphA2 protein levels in the tumors. These results suggest that molecular characteristics of the tumors in addition to EphA2 over-expression may be important for predicting responsiveness to EphA2-directed therapies. PMID:16533422

  19. Inhibition of Single Minded 2 gene expression mediates tumor-selective apoptosis and differentiation in human colon cancer cells.

    PubMed

    Aleman, Mireille J; DeYoung, Maurice Phil; Tress, Matthew; Keating, Patricia; Perry, Gary W; Narayanan, Ramaswamy

    2005-09-01

    A Down's syndrome associated gene, Single Minded 2 gene short form (SIM2-s), is specifically expressed in colon tumors but not in the normal colon. Antisense inhibition of SIM2-s in a RKO-derived colon carcinoma cell line causes growth inhibition, apoptosis, and inhibition of tumor growth in a nude mouse tumoriginicity model. The mechanism of cell death in tumor cells is unclear. In the present study, we investigated the pathways underlying apoptosis. Apoptosis was seen in a tumor cell-specific manner in RKO cells but not in normal renal epithelial cells, despite inhibition of SIM2-s expression in both of these cells by the antisense. Apoptosis was depended on WT p53 status and was caspase-dependent; it was inhibited by a pharmacological inhibitor of mitogen-activated protein kinase activity. Expression of a key stress response gene, growth arrest and DNA damage gene (GADD)45alpha, was up-regulated in antisense-treated tumor cells but not in normal cells. In an isogenic RKO cell line expressing stable antisense RNA to GADD45alpha, a significant protection of the antisense-induced apoptosis was seen. Whereas antisense-treated RKO cells did not undergo cell cycle arrest, several markers of differentiation were deregulated, including alkaline phosphatase activity, a marker of terminal differentiation. Protection of apoptosis and block of differentiation showed a correlation in the RKO model. Our results support the tumor cell-selective nature of SIM2-s gene function, provide a direct link between SIM2-s and differentiation, and may provide a model to identify SIM2-s targets. PMID:16129820

  20. Downregulation of stathmin 1 in human gallbladder carcinoma inhibits tumor growth in vitro and in vivo

    PubMed Central

    Wang, Jiwen; Yao, Yanli; Ming, Yue; Shen, Sheng; Wu, Nan; Liu, Jiaqi; Liu, Han; Suo, Tao; Pan, Hongtao; Zhang, Dexiang; Ding, Kan; Liu, Houbao

    2016-01-01

    Gallbladder carcinoma (GBC) is a highly lethal malignancy of the gastrointestinal tract. Despite extensive research, the underlying molecular mechanism of GBC remains largely unclear. Stathmin 1 (STMN1) is an important cytosolic protein associated with microtubule stability that was reported to be involved in tumorigenesis. Up to our knowledge, its role in gallbladder carcinoma has not been analyzed. In this study, we found that STMN1 was significantly highly expressed in GBC by immunohistochemistry (IHC). Further research demonstrated that silencing of STMN1 inhibited cell growth in vitro. Moreover, knockdown of STMN1 induced apoptosis and delayed G2/M phase transformation in GBC cells. Our data support a rationale for further studies that the silencing of STMN1 may regulate the activity of p38 MAPK kinase and p53/p21 signal pathway. Besides, xenografted gallbladder carcinoma cells growth were significantly impaired after STMN1 was silenced in vivo. These results suggested that STMN1 played an important role in cell proliferation and migration. This provided a potential clue for investigating the therapeutic target in GBC. PMID:27349455

  1. The Vascular Endothelial Growth Factor Receptor-2 Tyrosine Kinase Inhibitor Cediranib (Recentin; AZD2171) Inhibits Endothelial Cell Function and Growth of Human Renal Tumor Xenografts

    SciTech Connect

    Siemann, Dietmar W. Brazelle, W.D.; Juergensmeier, Juliane M.

    2009-03-01

    Purpose: The goal of this study was to examine the therapeutic potential of the vascular endothelial growth factor (VEGF) signaling inhibitor cediranib in a human model of renal cell carcinoma (Caki-1). Methods and Materials: The effects of cediranib treatment on in vitro endothelial cell function (proliferation, migration, and tube formation), as well as in vivo angiogenesis and tumor growth, were determined. Results: In vitro, cediranib significantly impaired the proliferation and migration of endothelial cells and their ability to form tubes, but had no effect on the proliferation of Caki-1 tumor cells. In vivo, cediranib significantly reduced Caki-1 tumor cell-induced angiogenesis, reduced tumor perfusion, and inhibited the growth of Caki-1 tumor xenografts. Conclusions: The present results are consistent with the notion that inhibition of VEGF signaling leads to an indirect (i.e., antiangiogenic) antitumor effect, rather than a direct effect on tumor cells. These results further suggest that inhibition of VEGF signaling with cediranib may impair the growth of renal cell carcinoma.

  2. Selenite Treatment Inhibits LAPC-4 Tumor Growth and Prostate-Specific Antigen Secretion in a Xenograft Model of Human Prostate Cancer

    SciTech Connect

    Bhattacharyya, Rumi S.; Husbeck, Bryan; Feldman, David; Knox, Susan J.

    2008-11-01

    Purpose: Selenium compounds have known chemopreventive effects on prostate cancer. However selenite, an inorganic form of selenium, has not been extensively studied as a treatment option for prostate cancer. Our previous studies have demonstrated the inhibition of androgen receptor expression and androgen stimulated prostate-specific antigen (PSA) expression by selenite in human prostate cancer cell lines. In this study, we investigated the in vivo effects of selenite as a therapy to treat mice with established LAPC-4 tumors. Methods and Materials: Male mice harboring androgen-dependent LAPC-4 xenograft tumors were treated with selenite (2 mg/kg intraperitoneally three times per week) or vehicle for 42 days. In addition, androgen-independent LAPC-4 xenograft tumors were generated in female mice over 4 to 6 months. Once established, androgen-independent LAPC-4 tumor fragments were passaged into female mice and were treated with selenite or vehicle for 42 days. Changes in tumor volume and serum PSA levels were assessed. Results: Selenite significantly decreased androgen-dependent LAPC-4 tumor growth in male mice over 42 days (p < 0.001). Relative tumor volume was decreased by 41% in selenite-treated animals compared with vehicle-treated animals. The inhibition of LAPC-4 tumor growth corresponded to a marked decrease in serum PSA levels (p < 0.01). In the androgen-independent LAPC-4 tumors in female mice, selenite treatment decreased tumor volume by 58% after 42 days of treatment (p < 0.001). Conclusions: These results suggest that selenite may have potential as a novel therapeutic agent to treat both androgen-dependent and androgen-independent prostate cancer.

  3. Inhibition of rate of tumor growth by creatine and cyclocreatine.

    PubMed Central

    Miller, E E; Evans, A E; Cohn, M

    1993-01-01

    Growth rate inhibition of subcutaneously implanted tumors results from feeding rats and athymic nude mice diets containing 1% cyclocreatine or 1%, 2%, 5%, or 10% creatine. The tumors studied included rat mammary tumors (Ac33tc in Lewis female rats and 13762A in Fischer 344 female rats), rat sarcoma MCI in Lewis male rats, and tumors resulting from the injection of two human neuroblastoma cell lines, IMR-5 and CHP-134, in athymic nude mice. Inhibition was observed regardless of the time experimental diets were administered, either at the time of tumor implantation or after the appearance of palpable tumors. For mammary tumor Ac33tc, the growth inhibition during 24 days after the implantation was approximately 50% for both 1% cyclocreatine and 1% creatine, and inhibition increased as creatine was increased from 2% to 10% of the diet. For the other rat mammary tumor (13762A), there was approximately 35% inhibition by both 1% cyclocreatine and 2% creatine. In the case of the MCI sarcoma, the inhibitory effect appeared more pronounced at earlier periods of growth, ranging from 26% to 41% for 1% cyclocreatine and from 30% to 53% for 1% creatine; there was no significant difference in growth rate between the tumors in the rats fed 1% and 5% creatine. The growth rate of tumors in athymic nude mice, produced by implantation of the human neuroblastoma IMR-5 cell line, appeared somewhat more effectively inhibited by 1% cyclocreatine than by 1% creatine, and 5% creatine feeding was most effective. For the CHP-134 cell line, 33% inhibition was observed for the 1% cyclocreatine diet and 71% for the 5% creatine diet. In several experiments, a delay in appearance of tumors was observed in animals on the experimental diets. In occasional experiments, neither additive inhibited tumor growth rate for the rat tumors or the athymic mouse tumors. Images Fig. 3 PMID:8475072

  4. Peloruside A Inhibits Growth of Human Lung and Breast Tumor Xenografts in an Athymic nu/nu Mouse Model.

    PubMed

    Meyer, Colin J; Krauth, Melissa; Wick, Michael J; Shay, Jerry W; Gellert, Ginelle; De Brabander, Jef K; Northcote, Peter T; Miller, John H

    2015-08-01

    Peloruside A is a microtubule-stabilizing agent isolated from a New Zealand marine sponge. Peloruside prevents growth of a panel of cancer cell lines at low nanomolar concentrations, including cell lines that are resistant to paclitaxel. Three xenograft studies in athymic nu/nu mice were performed to assess the efficacy of peloruside compared with standard anticancer agents such as paclitaxel, docetaxel, and doxorubicin. The first study examined the effect of 5 and 10 mg/kg peloruside (QD×5) on the growth of H460 non-small cell lung cancer xenografts. Peloruside caused tumor growth inhibition (%TGI) of 84% and 95%, respectively, whereas standard treatments with paclitaxel (8 mg/kg, QD×5) and docetaxel (6.3 mg/kg, Q2D×3) were much less effective (%TGI of 50% and 18%, respectively). In a second xenograft study using A549 lung cancer cells and varied schedules of dosing, activity of peloruside was again superior compared with the taxanes with inhibitions ranging from 51% to 74%, compared with 44% and 50% for the two taxanes. A third xenograft study in a P-glycoprotein-overexpressing NCI/ADR-RES breast tumor model showed that peloruside was better tolerated than either doxorubicin or paclitaxel. We conclude that peloruside is highly effective in preventing the growth of lung and P-glycoprotein-overexpressing breast tumors in vivo and that further therapeutic development is warranted. Mol Cancer Ther; 14(8); 1816-23. ©2015 AACR. PMID:26056149

  5. Combined inhibition of the mevalonate pathway with statins and zoledronic acid potentiates their anti-tumor effects in human breast cancer cells.

    PubMed

    Göbel, Andy; Thiele, Stefanie; Browne, Andrew J; Rauner, Martina; Zinna, Valentina M; Hofbauer, Lorenz C; Rachner, Tilman D

    2016-05-28

    Amino-bisphosphonates are antiresorptive drugs for the treatment of osteolytic bone metastases, which are frequently caused by breast and other solid tumors. Like statins, amino-bisphosphonates inhibit the mevalonate pathway. Direct anti-tumor effects of amino-bisphosphonates and statins have been proposed, although high concentrations are required to achieve these effects. Here, we demonstrate that the treatment of different human breast cancer cell lines (MDA-MB-231, MDA-Bone, and MDA-Met) by combined inhibition of the mevalonate pathway using statins and zoledronic acid at the same time significantly reduces the concentrations required to achieve a meaningful anti-tumor effect over a single agent approach (50% reduction of cell vitality and 4-fold increase of apoptosis; p < 0.05). The effects were mediated by suppressed protein geranylation that caused an accumulation of GTP-bound RhoA and CDC42. Importantly, the knockdown of both proteins prior to mevalonate pathway inhibition reduced apoptosis by up to 65% (p < 0.01), indicating the accumulation of the GTP-bound GTPases as the mediator of apoptosis. Our results point to effective anti-tumor effects in breast cancer by the combination of statins and zoledronic acid and warrant further validation in preclinical settings. PMID:26968247

  6. Daidzein suppresses tumor necrosis factor-α induced migration and invasion by inhibiting hedgehog/Gli1 signaling in human breast cancer cells.

    PubMed

    Bao, Cheng; Namgung, Hyeju; Lee, Jaehoo; Park, Hyun-Chang; Ko, Jiwon; Moon, Heejung; Ko, Hyuk Wan; Lee, Hong Jin

    2014-04-30

    In breast cancer, the cytokine tumor necrosis factor-α (TNF-α) induces cell invasion, although the molecular basis of it has not been clearly elucidated. In this study, we investigated the role of daidzein in regulating TNF-α induced cell invasion and the underlying molecular mechanisms. Daidzein inhibited TNF-α induced cellular migration and invasion in estrogen receptor (ER) negative MCF10DCIS.com human breast cancer cells. TNF-α activated Hedgehog (Hh) signaling by enhancing Gli1 nuclear translocation and transcriptional activity, which resulted in increased invasiveness; these effects were blocked by daidzein and the Hh signaling inhibitors, cyclopamine and vismodegib. Moreover, these compounds suppressed TNF-α induced matrix metalloproteinase (MMP)-9 mRNA expression and activity. Taken together, mammary tumor cell invasiveness was stimulated by TNF-α induced activation of Hh signaling; these effects were abrogated by daidzein, which suppressed Gli1 activation, thereby inhibiting migration and invasion. PMID:24724627

  7. Inhibition of Calcium-Activated Chloride Channel ANO1/TMEM16A Suppresses Tumor Growth and Invasion in Human Lung Cancer.

    PubMed

    Jia, Linghan; Liu, Wen; Guan, Lizhao; Lu, Min; Wang, KeWei

    2015-01-01

    Lung cancer or pulmonary carcinoma is primarily derived from epithelial cells that are thin and line on the alveolar surfaces of the lung for gas exchange. ANO1/TMEM16A, initially identified from airway epithelial cells, is a member of Ca2+-activated Cl- channels (CaCCs) that function to regulate epithelial secretion and cell volume for maintenance of ion and tissue homeostasis. ANO1/TMEM16A has recently been shown to be highly expressed in several epithelium originated carcinomas. However, the role of ANO1 in lung cancer remains unknown. In this study, we show that inhibition of calcium-activated chloride channel ANO1/TMEM16A suppresses tumor growth and invasion in human lung cancer. ANO1 is upregulated in different human lung cancer cell lines. Knocking-down ANO1 by small hairpin RNAs inhibited proliferation, migration and invasion of GLC82 and NCI-H520 cancel cells evaluated by CCK-8, would-healing, transwell and 3D soft agar assays. ANO1 protein is overexpressed in 77.3% cases of human lung adenocarcinoma tissues detected by immunohistochemistry. Furthermore, the tumor growth in nude mice implanted with GLC82 cells was significantly suppressed by ANO1 silencing. Taken together, our findings provide evidence that ANO1 overexpression contributes to tumor growth and invasion of lung cancer; and suppressing ANO1 overexpression may have therapeutic potential in lung cancer therapy. PMID:26305547

  8. Inhibition of Calcium-Activated Chloride Channel ANO1/TMEM16A Suppresses Tumor Growth and Invasion in Human Lung Cancer

    PubMed Central

    Jia, Linghan; Liu, Wen; Guan, Lizhao; Lu, Min; Wang, KeWei

    2015-01-01

    Lung cancer or pulmonary carcinoma is primarily derived from epithelial cells that are thin and line on the alveolar surfaces of the lung for gas exchange. ANO1/TMEM16A, initially identified from airway epithelial cells, is a member of Ca2+-activated Cl- channels (CaCCs) that function to regulate epithelial secretion and cell volume for maintenance of ion and tissue homeostasis. ANO1/TMEM16A has recently been shown to be highly expressed in several epithelium originated carcinomas. However, the role of ANO1 in lung cancer remains unknown. In this study, we show that inhibition of calcium-activated chloride channel ANO1/TMEM16A suppresses tumor growth and invasion in human lung cancer. ANO1 is upregulated in different human lung cancer cell lines. Knocking-down ANO1 by small hairpin RNAs inhibited proliferation, migration and invasion of GLC82 and NCI-H520 cancel cells evaluated by CCK-8, would-healing, transwell and 3D soft agar assays. ANO1 protein is overexpressed in 77.3% cases of human lung adenocarcinoma tissues detected by immunohistochemistry. Furthermore, the tumor growth in nude mice implanted with GLC82 cells was significantly suppressed by ANO1 silencing. Taken together, our findings provide evidence that ANO1 overexpression contributes to tumor growth and invasion of lung cancer; and suppressing ANO1 overexpression may have therapeutic potential in lung cancer therapy. PMID:26305547

  9. Tetrandrine Inhibits Wnt/β-Catenin Signaling and Suppresses Tumor Growth of Human Colorectal CancerS⃞

    PubMed Central

    He, Bai-Cheng; Gao, Jian-Li; Zhang, Bing-Qiang; Luo, Qing; Shi, Qiong; Kim, Stephanie H.; Huang, Enyi; Gao, Yanhong; Yang, Ke; Wagner, Eric R.; Wang, Linyuan; Tang, Ni; Luo, Jinyong; Liu, Xing; Li, Mi; Bi, Yang; Shen, Jikun; Luther, Gaurav; Hu, Ning; Zhou, Qixin; Luu, Hue H.; Haydon, Rex C.; Zhao, Yingming

    2011-01-01

    As one of the most common malignancies, colon cancer is initiated by abnormal activation of the Wnt/β-catenin pathway. Although the treatment options have increased for some patients, overall progress has been modest. Thus, there is a great need to develop new treatments. We have found that bisbenzylisoquinoline alkaloid tetrandrine (TET) exhibits anticancer activity. TET is used as a calcium channel blocker to treat hypertensive and arrhythmic conditions in Chinese medicine. Here, we investigate the molecular basis underlying TET's anticancer activity. We compare TET with six chemotherapy drugs in eight cancer lines and find that TET exhibits comparable anticancer activities with camptothecin, vincristine, paclitaxel, and doxorubicin, and better than that of 5-fluorouracil (5-FU) and carboplatin. TET IC50 is ≤5 μM in most of the tested cancer lines. TET exhibits synergistic anticancer activity with 5-FU and reduces migration and invasion capabilities of HCT116 cells. Furthermore, TET induces apoptosis and inhibits xenograft tumor growth of colon cancer. TET treatment leads to a decrease in β-catenin protein level in xenograft tumors, which is confirmed by T-cell factor/lymphocyte enhancer factor and c-Myc reporter assays. It is noteworthy that HCT116 cells with allelic oncogenic β-catenin deleted are less sensitive to TET-mediated inhibition of proliferation, viability, and xenograft tumor growth. Thus, our findings strongly suggest that the anticancer effect of TET in colon cancer may be at least in part mediated by targeting β-catenin activity. Therefore, TET may be used alone or in combination as an effective anticancer agent. PMID:20978119

  10. Anticancer activity of TTAC-0001, a fully human anti-vascular endothelial growth factor receptor 2 (VEGFR-2/KDR) monoclonal antibody, is associated with inhibition of tumor angiogenesis

    PubMed Central

    Kim, Dong Geon; Jin, Younggeon; Jin, Juyoun; Yang, Heekyoung; Joo, Kyeung Min; Lee, Weon Sup; Shim, Sang Ryeol; Kim, Sung-Woo; Yoo, Jinsang; Lee, Sang Hoon; Yoo, Jin-San; Nam, Do-Hyun

    2015-01-01

    Vascular endothelial growth factor (VEGF) and its receptors are considered the primary cause of tumor-induced angiogenesis. Specifically, VEGFR-2/kinase insert domain receptor (KDR) is part of the major signaling pathway that plays a significant role in tumor angiogenesis, which is associated with the development of various types of tumor and metastasis. In particular, KDR is involved in tumor angiogenesis as well as cancer cell growth and survival. In this study, we evaluated the therapeutic potential of TTAC-0001, a fully human antibody against VEGFR-2/KDR. To assess the efficacy of the antibody and pharmacokinetic (PK) relationship in vivo, we tested the potency of TTAC-0001 in glioblastoma and colorectal cancer xenograft models. Antitumor activity of TTAC-0001 in preclinical models correlated with tumor growth arrest, induction of tumor cell apoptosis, and inhibition of angiogenesis. We also evaluated the combination effect of TTAC-0001 with a chemotherapeutic agent in xenograft models. We were able to determine the relationship between PK and the efficacy of TTAC-0001 through in vivo single-dose PK study. Taken together, our data suggest that targeting VEGFR-2 with TTAC-0001 could be a promising approach for cancer treatment. PMID:26325365

  11. Tumor-targeting Salmonella typhimurium A1-R inhibits human prostate cancer experimental bone metastasis in mouse models

    PubMed Central

    Toneri, Makoto; Miwa, Shinji; Zhang, Yong; Hu, Cameron; Yano, Shuya; Matsumoto, Yasunori; Bouvet, Michael; Nakanishi, Hayao; Hoffman, Robert M.; Zhao, Ming

    2015-01-01

    Bone metastasis is a frequent occurrence in prostate cancer patients and often is lethal. Zoledronic acid (ZOL) is often used for bone metastasis with limited efficacy. More effective models and treatment methods are required to improve the outcome of prostate cancer patients. In the present study, the effects of tumor-targeting Salmonella typhimurium A1-R were analyzed in vitro and in vivo on prostate cancer cells and experimental bone metastasis. Both ZOL and S. typhimurium A1-R inhibited the growth of PC-3 cells expressing red fluorescent protien in vitro. To investigate the efficacy of S. typhimurium A1-R on prostate cancer experimental bone metastasis, we established models of both early and advanced stage bone metastasis. The mice were treated with ZOL, S. typhimurium A1-R, and combination therapy of both ZOL and S. typhimurium A1-R. ZOL and S. typhimurium A1-R inhibited the growth of solitary bone metastases. S. typhimurium A1-R treatment significantly decreased bone metastasis and delayed the appearance of PC-3 bone metastases of multiple mouse models. Additionally, S. typhimurium A1-R treatment significantly improved the overall survival of the mice with multiple bone metastases. The results of the present study indicate that S. typhimurium A1-R is useful to prevent and inhibit prostate cancer bone metastasis and has potential for future clinical use in the adjuvant setting. PMID:26431498

  12. Simvastatin Inhibits Toll-like Receptor 8 (TLR8) Signaling in Primary Human Monocytes and Spontaneous Tumor Necrosis Factor Production from Rheumatoid Synovial Membrane Cultures

    PubMed Central

    Mullen, Lisa; Ferdjani, Jason; Sacre, Sandra

    2015-01-01

    Simvastatin has been shown to have antiinflammatory effects that are independent of its serum cholesterol lowering action, but the mechanisms by which these antiinflammatory effects are mediated have not been elucidated. To explore the mechanism involved, the effect of simvastatin on toll-like receptor (TLR) signaling in primary human monocytes was investigated. A short pretreatment with simvastatin dose-dependently inhibited the production of tumor necrosis factor (TNF)-α in response to TLR8 activation (but not TLR2, -4 or -5). Statins are known inhibitors of the cholesterol biosynthetic pathway, but, intriguingly, TLR8 inhibition could not be reversed by addition of mevalonate or geranylgeranyl pyrophosphate, downstream products of cholesterol biosynthesis. TLR8 signaling was examined in HEK 293 cells stably expressing TLR8, where simvastatin inhibited I kappa B kinase (IKK)α/β phosphorylation and subsequent nuclear factor (NF)-κB activation without affecting the pathway to activating protein-1 (AP-1). Because simvastatin has been reported to have antiinflammatory effects in RA patients and TLR8 signaling contributes to TNF production in human RA synovial tissue in culture, simvastatin was tested in these cultures. Simvastatin significantly inhibited the spontaneous release of TNF in this model, which was not reversed by mevalonate. Together, these results demonstrate a hitherto unrecognized mechanism of simvastatin inhibition of TLR8 signaling that may in part explain its beneficial antiinflammatory effects. PMID:26322850

  13. Emblica officinalis Extract Induces Autophagy and Inhibits Human Ovarian Cancer Cell Proliferation, Angiogenesis, Growth of Mouse Xenograft Tumors

    PubMed Central

    De, Alok; De, Archana; Papasian, Chris; Hentges, Shane; Banerjee, Snigdha; Haque, Inamul; Banerjee, Sushanta K.

    2013-01-01

    Patients with ovarian cancer (OC) may be treated with surgery, chemotherapy and/or radiation therapy, although none of these strategies are very effective. Several plant-based natural products/dietary supplements, including extracts from Emblicaofficinalis (Amla), have demonstrated potent anti-neoplastic properties. In this study we determined that Amla extract (AE) has anti-proliferative effects on OC cells under both in vitro and in vivo conditions. We also determined the anti-proliferative effects one of the components of AE, quercetin, on OC cells under in vitro conditions. AE did not induce apoptotic cell death, but did significantly increase the expression of the autophagic proteins beclin1 and LC3B-II under in vitro conditions. Quercetin also increased the expression of the autophagic proteins beclin1 and LC3B-II under in vitro conditions. AE also significantly reduced the expression of several angiogenic genes, including hypoxia-inducible factor 1α (HIF-1α) in OVCAR3 cells. AE acted synergistically with cisplatin to reduce cell proliferation and increase expression of the autophagic proteins beclin1 and LC3B-II under in vitro conditions. AE also had anti-proliferative effects and induced the expression of the autophagic proteins beclin1 and LC3B-II in mouse xenograft tumors. Additionally, AE reduced endothelial cell antigen – CD31 positive blood vessels and HIF-1α expression in mouse xenograft tumors. Together, these studies indicate that AE inhibits OC cell growth both in vitro and in vivo possibly via inhibition of angiogenesis and activation of autophagy in OC. Thus AE may prove useful as an alternative or adjunct therapeutic approach in helping to fight OC. PMID:24133573

  14. Norcantharidin inhibits tumor growth and vasculogenic mimicry of human gallbladder carcinomas by suppression of the PI3-K/MMPs/Ln-5γ2 signaling pathway

    PubMed Central

    2014-01-01

    NCTD or TIMP-2 group; (all P < 0.01, vs. control group); NCTD down-regulated expression of these VM signaling-related markers in vitro and in vivo. Conclusions NCTD inhibited tumor growth and VM of human GBCs in vitro and in vivo by suppression of the PI3-K/MMPs/Ln-5γ2 signaling pathway. It is firstly concluded that NCTD may be a potential anti-VM agent for human GBCs. PMID:24628713

  15. RNA Interference-Mediated Inhibition of Erythropoietin Receptor Expression Suppresses Tumor Growth and Invasiveness in A2780 Human Ovarian Carcinoma Cells

    PubMed Central

    Paragh, Gyorgy; Kumar, Suresh M.; Rakosy, Zsuzsa; Choi, Soek-Choel; Xu, Xiaowei; Acs, Geza

    2009-01-01

    Although recombinant human erythropoietin (rHuEpo) has revolutionized the treatment of anemia, recent clinical trials suggested that rHuEpo use may be associated with decreased survival in cancer patients. Although the expression of erythropoietin (Epo) receptor (EpoR) has been demonstrated in various human cancers, the effect of exogenous Epo on the growth and therapy resistance of EpoR-bearing tumor cells is unclear at present. In the current study, we examined the hypothesis that EpoR may contribute to tumor growth independent of Epo in A2780 human ovarian carcinoma cells. A2780 human ovarian carcinoma cells showed high levels of EpoR expression, but lacked expression of Epo mRNA and biologically active Epo protein under both normoxic and hypoxic conditions. Exogenous Epo did not stimulate EpoR-mediated signaling, proliferation, invasiveness, or resistance to cytotoxic drugs in A2780 cells. In contrast, specific inhibition of EpoR expression using a short hairpin RNA (shRNA) expression plasmid resulted in markedly reduced proliferation and invasiveness in vitro. In addition, inhibition of EpoR expression led to abrogated in vivo ovarian cancer cell growth in a tumor xenograft system and resulted in decreased EpoR signaling. Our findings suggest that EpoR may be constitutively active in some cancer cells in the absence of Epo and provide the first evidence for a potential role of an Epo-independent, EpoR-mediated pathway in the growth of some human cancers. PMID:19264915

  16. The coffee diterpene kahweol inhibits tumor necrosis factor-{alpha}-induced expression of cell adhesion molecules in human endothelial cells

    SciTech Connect

    Kim, Hyung Gyun; Kim, Ji Young; Hwang, Yong Pil; Lee, Kyung Jin; Lee, Kwang Youl; Kim, Dong Hee; Kim, Dong Hyun; Jeong, Hye Gwang . E-mail: hgjeong@chosun.ac.kr

    2006-12-15

    Endothelial cells produce adhesion molecules after being stimulated with various inflammatory cytokines. These adhesion molecules play an important role in the development of atherogenesis. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of kahweol, a coffee-specific diterpene. This study examined the effects of kahweol on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. Kahweol inhibited the adhesion of TNF{alpha}-induced monocytes to endothelial cells and suppressed the TNF{alpha}-induced protein and mRNA expression of the cell adhesion molecules, VCAM-1 and ICAM-1. Furthermore, kahweol inhibited the TNF{alpha}-induced JAK2-PI3K/Akt-NF-{kappa}B activation pathway in these cells. Overall, kahweol has anti-inflammatory and anti-atherosclerotic activities, which occurs partly by down-regulating the pathway that affects the expression and interaction of the cell adhesion molecules on endothelial cells.

  17. A Humanized Anti-VEGF Rabbit Monoclonal Antibody Inhibits Angiogenesis and Blocks Tumor Growth in Xenograft Models

    PubMed Central

    Zhang, Yongke; Yu, Qiu; Lee, Jonathan; Li, Mingzhen; Song, Jialiang; Chen, Jungang; Dai, Jihong; Couto, Fernando Jose Rebelo Do; An, Zhiqiang; Zhu, Weimin; Yu, Guo-Liang

    2010-01-01

    Rabbit antibodies have been widely used in research and diagnostics due to their high antigen specificity and affinity. Though these properties are also highly desirable for therapeutic applications, rabbit antibodies have remained untapped for human disease therapy. To evaluate the therapeutic potential of rabbit monoclonal antibodies (RabMAbs), we generated a panel of neutralizing RabMAbs against human vascular endothelial growth factor-A (VEGF). These neutralizing RabMAbs are specific to VEGF and do not cross-react to other members of the VEGF protein family. Guided by sequence and lineage analysis of a panel of neutralizing RabMAbs, we humanized the lead candidate by substituting non-critical residues with human residues within both the frameworks and the CDR regions. We showed that the humanized RabMAb retained its parental biological properties and showed potent inhibition of the growth of H460 lung carcinoma and A673 rhabdomyosarcoma xenografts in mice. These studies provide proof of principle for the feasibility of developing humanized RabMAbs as therapeutics. PMID:20140208

  18. Rapid decrease in tumor perfusion following VEGF blockade predicts long-term tumor growth inhibition in preclinical tumor models.

    PubMed

    Eichten, Alexandra; Adler, Alexander P; Cooper, Blerta; Griffith, Jennifer; Wei, Yi; Yancopoulos, George D; Lin, Hsin Chieh; Thurston, Gavin

    2013-04-01

    Vascular endothelial growth factor (VEGF) is a key upstream mediator of tumor angiogenesis, and blockade of VEGF can inhibit tumor angiogenesis and decrease tumor growth. However, not all tumors respond well to anti-VEGF therapy. Despite much effort, identification of early response biomarkers that correlate with long-term efficacy of anti-VEGF therapy has been difficult. These difficulties arise in part because the functional effects of VEGF inhibition on tumor vessels are still unclear. We therefore assessed rapid molecular, morphologic and functional vascular responses following treatment with aflibercept (also known as VEGF Trap or ziv-aflibercept in the United States) in preclinical tumor models with a range of responses to anti-VEGF therapy, including Colo205 human colorectal carcinoma (highly sensitive), C6 rat glioblastoma (moderately sensitive), and HT1080 human fibrosarcoma (resistant), and correlated these changes to long-term tumor growth inhibition. We found that an overall decrease in tumor vessel perfusion, assessed by dynamic contrast-enhanced ultrasound (DCE-US), and increases in tumor hypoxia correlated well with long-term tumor growth inhibition, whereas changes in vascular gene expression and microvessel density did not. Our findings support previous clinical studies showing that decreased tumor perfusion after anti-VEGF therapy (measured by DCE-US) correlated with response. Thus, measuring tumor perfusion changes shortly after treatment with VEGF inhibitors, or possibly other anti-angiogenic therapies, may be useful to predict treatment efficacy. PMID:23238831

  19. Inhibition of human tumor xenograft growth in nude mice by a conjugate of monoclonal antibody LA22 to epidermal growth factor receptor with anti-tumor antibiotics mitomycin C

    SciTech Connect

    Shao Wei; Zhao Shan; Liu Zhaofei; Zhang Jianzhong; Ma Shujun; Sato, J. Denry; Zhang Peng; Tong Mei; Han Jiping; Wang Yan; Bai Dongmei; Wang Fan . E-mail: wangfan@bjmu.edu.cn; Sun Le . E-mail: lsun@welsonpharma.com

    2006-10-20

    Anti-EGFR monoclonal antibodies LA22 and Erbitux bind to different epitopes of EGFR. The chemimmunoconjugates of MMC with LA22 or Erbitux were prepared, and in vitro cytotoxicity assays with A549 cells showed that LA22-MMC was much more potent than Erbitux or Erbitux-MMC. Viabilities of A549 cells treated with LA22-MMC, Erbitux or Erbitux-MMC were 35%, 94%, and 81%, respectively. Immunoscintigraphy of xenografts of human A431 and A549 cells in nude mice both showed that {sup 125}I-labeled-LA22-MMC enriched in tumor sites prominently. Most importantly, in vivo assays showed LA22-MMC was significantly more effective than free drug MMC in the treatment of subcutaneous xenografts of human A431 cells in nude mice (83% inhibition for LA22-MMC and 30% for MMC). We concluded that LA22-MMC could be a very potent drug for treatment of solid tumors.

  20. Inhibition of Vascularization in Tumor Growth

    NASA Astrophysics Data System (ADS)

    Scalerandi, M.; Sansone, B. Capogrosso

    2002-11-01

    The transition to a vascular phase is a prerequisite for fast tumor growth. During the avascular phase, the neoplasm feeds only from the (relatively few) existing nearby blood vessels. During angiogenesis, the number of capillaries surrounding and infiltrating the tumor increases dramatically. A model which includes physical and biological mechanisms of the interactions between the tumor and vascular growth describes the avascular-vascular transition. Numerical results agree with clinical observations and predict the influence of therapies aiming to inhibit the transition.

  1. Ehrlich tumor inhibition using doxorubicin containing liposomes.

    PubMed

    Elbialy, Nihal Saad; Mady, Mohsen Mahmoud

    2015-04-01

    Ehrlich tumors were grown in female balb mice by subcutaneous injection of Ehrlich ascites carcinoma cells. Mice bearing Ehrlich tumor were injected with saline, DOX in solution or DOX encapsulated within liposomes prepared from DMPC/CHOL/DPPG/PEG-PE (100:100:60:4) in molar ratio. Cytotoxicity assay showed that the IC50 of liposomes containing DOX was greater than that DOX only. Tumor growth inhibition curves in terms of mean tumor size (cm(3)) were presented. All the DOX formulations were effective in preventing tumor growth compared to saline. Treatment with DOX loaded liposomes displayed a pronounced inhibition in tumor growth than treatment with DOX only. Histopathological examination of the entire tumor sections for the various groups revealed marked differences in cellular features accompanied by varying degrees in necrosis percentage ranging from 12% for saline treated mice to 70% for DOX loaded liposome treated mice. The proposed liposomal formulation can efficiently deliver the drug into the tumor cells by endocytosis (or passive diffusion) and lead to a high concentration of DOX in the tumor cells. The study showed that the formulation of liposomal doxorubicin improved the therapeutic index of DOX and had increased anti-tumor activity against Ehrlich tumor models. PMID:25972739

  2. Niclosamide inhibits epithelial-mesenchymal transition and tumor growth in lapatinib-resistant human epidermal growth factor receptor 2-positive breast cancer.

    PubMed

    Liu, Junjun; Chen, Xiaosong; Ward, Toby; Mao, Yan; Bockhorn, Jessica; Liu, Xiaofei; Wang, Gen; Pegram, Mark; Shen, Kunwei

    2016-02-01

    Acquired resistance to lapatinib, a human epidermal growth factor receptor 2 kinase inhibitor, remains a clinical problem for women with human epidermal growth factor receptor 2-positive advanced breast cancer, as metastasis is commonly observed in these patients. Niclosamide, an anti-helminthic agent, has recently been shown to exhibit cytotoxicity to tumor cells with stem-like characteristics. This study was designed to identify the mechanisms underlying lapatinib resistance and to determine whether niclosamide inhibits lapatinib resistance by reversing epithelial-mesenchymal transition. Here, two human epidermal growth factor receptor 2-positive breast cancer cell lines, SKBR3 and BT474, were exposed to increasing concentrations of lapatinib to establish lapatinib-resistant cultures. Lapatinib-resistant SKBR3 and BT474 cells exhibited up-regulation of the phenotypic epithelial-mesenchymal transition markers Snail, vimentin and α-smooth muscle actin, accompanied by activation of nuclear factor-кB and Src and a concomitant increase in stem cell marker expression (CD44(high)/CD24(low)), compared to naive lapatinib-sensitive SKBR3 and BT474 cells, respectively. Interestingly, niclosamide reversed epithelial-mesenchymal transition, induced apoptosis and inhibited cell growth by perturbing aberrant signaling pathway activation in lapatinib-resistant human epidermal growth factor receptor 2-positive cells. The ability of niclosamide to alleviate stem-like phenotype development and invasion was confirmed. Collectively, our results demonstrate that lapatinib resistance correlates with epithelial-mesenchymal transition and that niclosamide inhibits lapatinib-resistant cell viability and epithelial-mesenchymal transition. These findings suggest a role of niclosamide or derivatives optimized for more favorable bioavailability not only in reversing lapatinib resistance but also in reducing metastatic potential during the treatment of human epidermal growth factor receptor

  3. Targeting activating mutations of EZH2 leads to potent cell growth inhibition in human melanoma by derepression of tumor suppressor genes

    PubMed Central

    Tiffen, Jessamy C.; Gunatilake, Dilini; Gallagher, Stuart J.; Gowrishankar, Kavitha; Heinemann, Anja; Cullinane, Carleen; Dutton-Regester, Ken; Pupo, Gulietta M.; Strbenac, Dario; Yang, Jean Y.; Madore, Jason; Mann, Graham J.; Hayward, Nicholas K.; McArthur, Grant A.; Filipp, Fabian V.; Hersey, Peter

    2015-01-01

    The epigenetic modifier EZH2 is part of the polycomb repressive complex that suppresses gene expression via histone methylation. Activating mutations in EZH2 are found in a subset of melanoma that contributes to disease progression by inactivating tumor suppressor genes. In this study we have targeted EZH2 with a specific inhibitor (GSK126) or depleted EZH2 protein by stable shRNA knockdown. We show that inhibition of EZH2 has potent effects on the growth of both wild-type and EZH2 mutant human melanoma in vitro particularly in cell lines harboring the EZH2Y646 activating mutation. This was associated with cell cycle arrest, reduced proliferative capacity in both 2D and 3D culture systems, and induction of apoptosis. The latter was caspase independent and mediated by the release of apoptosis inducing factor (AIFM1) from mitochondria. Gene expression arrays showed that several well characterized tumor suppressor genes were reactivated by EZH2 inhibition. This included activating transcription factor 3 (ATF3) that was validated as an EZH2 target gene by ChIP-qPCR. These results emphasize a critical role for EZH2 in the proliferation and viability of melanoma and highlight the potential for targeted therapy against EZH2 in treatment of patients with melanoma. PMID:26304929

  4. Anti-tumor activity of the novel hexahydrocannabinol analog LYR-8 in Human colorectal tumor xenograft is mediated through the inhibition of Akt and hypoxia-inducible factor-1α activation.

    PubMed

    Thapa, Dinesh; Kang, Youra; Park, Pil-Hoon; Noh, Seok Kyun; Lee, Yong Rok; Han, Sung Soo; Ku, Sae Kwang; Jung, Yunjin; Kim, Jung-Ae

    2012-01-01

    Cannabinoid compounds have been shown to exert anti-tumor effects by affecting angiogenesis, invasion, and metastasis. In the present study, we examined the action mechanism by which LYR-8, a novel hexahydrocannabinol analog, exerts anti-angiogenic and anti-tumor activity in human cancer xenografts. In the xenografted tumor tissues, LYR-8 significantly reduced the expression of hypoxia-inducible factor-1 alpha (HIF-1α), a transcription factor responsible for induction of angiogenesis-promoting factors, and its target genes, vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2). In HT-29 human colon cancer cells treated with a hypoxia-inducing agent (CoCl(2)), LYR-8 dose-dependently suppressed the induction of HIF-1α and subsequently its targets, VEGF and COX-2. In addition, highly elevated prostaglandin E(2) (PGE(2)) concentrations in CoCl(2)-treated HT-29 cells were also significantly suppressed by LYR-8. However, LYR-8 alone in the absence of CoCl(2) did not alter the basal expression of VEGF and COX-2, or PGE(2) production. Furthermore, LYR-8 effectively suppressed Akt signaling, which corresponded to the suppression of CoCl(2)-induced HIF-1α accumulation. Taken together, LYR-8 exerts anti-tumor effects through the inhibition of Akt and HIF-1α activation, and subsequently suppressing factors regulating tumor microenvironment, such as VEGF and COX-2. These results indicate a novel function of cannabinoid-like compound LYR-8 as an anti-tumor agent with a HIF-1α inhibitory activity. PMID:22687485

  5. A novel quinoline, MT477: suppresses cell signaling through Ras molecular pathway, inhibits PKC activity, and demonstrates in vivo anti-tumor activity against human carcinoma cell lines.

    PubMed

    Jasinski, Piotr; Welsh, Brandon; Galvez, Jorge; Land, David; Zwolak, Pawel; Ghandi, Lori; Terai, Kaoru; Dudek, Arkadiusz Z

    2008-06-01

    MT477 is a novel thiopyrano[2,3-c]quinoline that has been identified using molecular topology screening as a potential anticancer drug with a high activity against protein kinase C (PKC) isoforms. The objective of the present study was to determine the mechanism of action of MT477 and its activity against human cancer cell lines. MT477 interfered with PKC activity as well as phosphorylation of Ras and ERK1/2 in H226 human lung carcinoma cells. It also induced poly-caspase-dependent apoptosis. MT477 had a dose-dependent (0.006 to 0.2 mM) inhibitory effect on cellular proliferation of H226, MCF-7, U87, LNCaP, A431 and A549 cancer cell lines as determined by in vitro proliferation assays. Two murine xenograft models of human A431 and H226 lung carcinoma were used to evaluate tumor response to intraperitoneal administration of MT477 (33 microg/kg, 100 microg/kg, and 1 mg/kg). Tumor growth was inhibited by 24.5% in A431 and 43.67% in H226 xenografts following MT477 treatment, compared to vehicle controls (p < 0.05). In conclusion, our empirical findings are consistent with molecular modeling of MT477's activity against PKC. We also found, however, that its mechanism of action occurs through suppressing Ras signaling, indicating that its effects on apoptosis and tumor growth in vivo may be mediated by Ras as well as PKC. We propose, therefore, that MT477 warrants further development as an anticancer drug. PMID:17957339

  6. Adriamycin resistance-associated prohibitin gene inhibits proliferation of human osteosarcoma MG63 cells by interacting with oncogenes and tumor suppressor genes

    PubMed Central

    Du, Min-Dong; He, Kai-Yi; Qin, Gang; Chen, Jin; Li, Jin-Yi

    2016-01-01

    The resistance of cancer cells to chemotherapeutic agents is a major obstacle for successful chemotherapy, and the mechanism of chemoresistance remains unclear. The present study developed an adriamycin-resistant human osteosarcoma MG-63 sub-line (MG-63/ADR), and identified differentially expressed proteins that may be associated with adriamycin resistance. Two dimensional gel electrophoresis, matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis and a protein identification assay were performed. Western blot analysis was used to examine the prohibitin (PHB) levels in the MG-63/ADR cells. Quantitative polymerase chain reaction was utilized to detect adriamycin resistant-associated genes. Laser-scanning confocal microscope was employed to examine the colocalization of PHB with v-myc avian myelocytomatosis viral oncogene homolog (c-myc), FBJ murine osteosarcoma viral oncogene homolog (c-fos), tumor protein p53 and retinoblastoma 1 (Rb). In addition, the full length of the open reading frame of human PHB was subcloned into a lentiviral vector pLVX-puro. The proliferative rate of MG-63 cells was also investigated. The overall protein expression in MG-63/ADR cells was clearly suppressed. Three notable protein regions, representing high mobility group box 1, Ras homolog gene family, member A, and PHB, were identified to be significantly altered in MG-63/ADR cells when compared with its parental cells. Therefore, PHB modulated the chemoresistance of MG-63/ADR cells by interacting with multiple oncogenes or tumor suppressor genes (c-myc, c-fos, p53 and Rb). In addition, overexpression of PHB decreases the proliferative rate of MG-63 cells. In conclusion, PHB is an adriamycin resistance-associated gene, which may inhibit the proliferation of human osteosarcoma MG-63 cells by interacting with the oncogenes or tumor suppressor genes, c-myc, c-fos, p53 and Rb. PMID:27602127

  7. Inhibition of sup 125 I organification and thyroid hormone release by interleukin-1, tumor necrosis factor-alpha, and interferon-gamma in human thyrocytes in suspension culture

    SciTech Connect

    Sato, K.; Satoh, T.; Shizume, K.; Ozawa, M.; Han, D.C.; Imamura, H.; Tsushima, T.; Demura, H.; Kanaji, Y.; Ito, Y. )

    1990-06-01

    To elucidate the mechanism of decreased 131I uptake by the thyroid gland in patients with subacute thyroiditis and painless thyroiditis, human thyroid follicles were cultured with interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF alpha), and/or interferon-gamma (IFN gamma), and the effects of these cytokines on thyroid function were studied in vitro. When human thyrocytes were cultured in RPMI-1640 medium containing 0.5% fetal calf serum and TSH for 5-8 days, the cells incorporated 125I, synthesized de novo (125I)iodotyrosines and (125I)iodothyronines, and secreted (125I)T4 and (125I)T3 into the medium. IL-1 alpha and IL-1 beta inhibited 125I incorporation and (125I)iodothyronine release in a concentration-dependent manner. The minimal inhibitory effect was detected at 10 pg/ml. Electron microscopic examination revealed a marked decrease in lysosome formation in IL-1-treated thyrocytes. TNF alpha and IFN gamma also inhibited thyroid function in a concentration-dependent manner. Furthermore, when thyrocytes were cultured with IL-1, TNF alpha and IFN gamma, these cytokines more than additively inhibited thyroid function. Although the main mechanism of 131I uptake suppression in the thyroid gland in subacute thyroiditis is due to cellular damage and suppression of TSH release, our present findings suggest that IL-1, TNF alpha, and IFN gamma produced in the inflammatory process within the thyroid gland further inhibit iodine incorporation and at least partly account for the decreased 131I uptake by the thyroid gland in destruction-induced hyperthyroidism.

  8. Transient exposure of human myoblasts to tumor necrosis factor-alpha inhibits serum and insulin-like growth factor-I stimulated protein synthesis.

    PubMed

    Frost, R A; Lang, C H; Gelato, M C

    1997-10-01

    Tumor necrosis factor-alpha (TNF-alpha) induces cachexia and is postulated to be responsible for muscle wasting in several pathophysiological conditions. The purpose of the present study was to investigate whether exposure of human myoblasts to TNF-alpha could directly inhibit the ability of serum or insulin-like growth factor I (IGF-I) to stimulate protein synthesis as assessed by the incorporation of [3H]phenylalanine into protein. Serum and IGF-I stimulated protein synthesis dose dependently. Half-maximal stimulation of protein synthesis occurred at 05% serum and 8 ng/ml of IGF-I, respectively. TNF-alpha inhibited IGF-I-stimulated protein synthesis in a dose-dependent manner. Additionally, as little as 2 ng/ml of TNF-alpha impaired the ability of IGF-I to stimulate protein synthesis by 33% and, at a dose of 100 ng/ml, TNF-alpha completely prevented the increase in protein synthesis induced by either serum or a maximally stimulating dose of IGF-I. Inhibition of protein synthesis was independent of whether TNF-alpha and growth factors were added to cells simultaneously or if the cells were pretreated with growth factors. Exposure ofmyoblasts to TNF-alpha for 10 min completely inhibited serum-induced stimulation of protein synthesis. TNF-alpha inhibited protein synthesis up to 48 h after addition of the cytokine. TNF-alpha also inhibited serum-stimulated protein synthesis in human myoblasts that were differentiated into myotubes. In contrast, exposure of myoblasts to TNF-alpha had no effect on IGF-I binding and failed to alter the ability of either IGF-I or serum to stimulate [3H]thymidine uptake. These data indicate that transient exposure of myoblasts or myotubes to TNF-alpha inhibits protein synthesis. Thus, the anabolic actions of IGF-I on muscle protein synthesis may be impaired during catabolic conditions in which TNF-alpha is over expressed. PMID:9322924

  9. Silencing NFBD1/MDC1 enhances the radiosensitivity of human nasopharyngeal cancer CNE1 cells and results in tumor growth inhibition

    PubMed Central

    Wang, Z; Zeng, Q; Chen, T; Liao, K; Bu, Y; Hong, S; Hu, G

    2015-01-01

    NFBD1 functions in cell cycle checkpoint activation and DNA repair following ionizing radiation (IR). In this study, we defined the NFBD1 as a tractable molecular target to radiosensitize nasopharyngeal carcinoma (NPC) cells. Silencing NFBD1 using lentivirus-mediated shRNA-sensitized NPC cells to radiation in a dose-dependent manner, increasing apoptotic cell death, decreasing clonogenic survival and delaying DNA damage repair. Furthermore, downregulation of NFBD1 inhibited the amplification of the IR-induced DNA damage signal, and failed to accumulate and retain DNA damage-response proteins at the DNA damage sites, which leaded to defective checkpoint activation following DNA damage. We also implicated the involvement of NFBD1 in IR-induced Rad51 and DNA-dependent protein kinase catalytic subunit foci formation. Xenografts models in nude mice showed that silencing NFBD1 significantly enhanced the antitumor activity of IR, leading to tumor growth inhibition of the combination therapy. Our studies suggested that a combination of gene therapy and radiation therapy may be an effective strategy for human NPC treatment. PMID:26247734

  10. Silencing NFBD1/MDC1 enhances the radiosensitivity of human nasopharyngeal cancer CNE1 cells and results in tumor growth inhibition.

    PubMed

    Wang, Z; Zeng, Q; Chen, T; Liao, K; Bu, Y; Hong, S; Hu, G

    2015-01-01

    NFBD1 functions in cell cycle checkpoint activation and DNA repair following ionizing radiation (IR). In this study, we defined the NFBD1 as a tractable molecular target to radiosensitize nasopharyngeal carcinoma (NPC) cells. Silencing NFBD1 using lentivirus-mediated shRNA-sensitized NPC cells to radiation in a dose-dependent manner, increasing apoptotic cell death, decreasing clonogenic survival and delaying DNA damage repair. Furthermore, downregulation of NFBD1 inhibited the amplification of the IR-induced DNA damage signal, and failed to accumulate and retain DNA damage-response proteins at the DNA damage sites, which leaded to defective checkpoint activation following DNA damage. We also implicated the involvement of NFBD1 in IR-induced Rad51 and DNA-dependent protein kinase catalytic subunit foci formation. Xenografts models in nude mice showed that silencing NFBD1 significantly enhanced the antitumor activity of IR, leading to tumor growth inhibition of the combination therapy. Our studies suggested that a combination of gene therapy and radiation therapy may be an effective strategy for human NPC treatment. PMID:26247734

  11. BMP4/Thrombospondin-1 loop paracrinically inhibits tumor angiogenesis and suppresses the growth of solid tumors.

    PubMed

    Tsuchida, R; Osawa, T; Wang, F; Nishii, R; Das, B; Tsuchida, S; Muramatsu, M; Takahashi, T; Inoue, T; Wada, Y; Minami, T; Yuasa, Y; Shibuya, M

    2014-07-17

    Bone morphogenetic protein 4 (BMP4) has potential as an anticancer agent. Recent studies have suggested that BMP4 inhibits the survival of cancer stem cells (CSCs) of neural and colon cancers. Here, we showed that BMP4 paracrinically inhibited tumor angiogenesis via the induction of Thrombospondin-1 (TSP1), and consequently suppressed tumor growth in vivo. Although HeLa (human cervical cancer), HCI-H460-LNM35 (highly metastatic human lung cancer) and B16 (murine melanoma) cells did not respond to the BMP4 treatment in vitro, the growth of xeno- and allografts of these cells was suppressed via reductions in tumor angiogenesis after intraperitoneal treatment with BMP4. When we assessed the mRNA expression of major angiogenesis-related factors in grafted tumors, we found that the expression of TSP1 was significantly upregulated by BMP4 administration. We then confirmed that BMP4 was less effective in suppressing the tumor growth of TSP1-knockdown cancer cells. Furthermore, we found that BMP4 reduced vascular endothelial growth factor (VEGF) expression in vivo in a TSP1-dependent manner, which indicates that BMP4 interfered with the stabilization of tumor angiogenesis. In conclusion, the BMP4/TSP1 loop paracrinically suppressed tumor angiogenesis in the tumor microenvironment, which subsequently reduced the growth of tumors. BMP4 may become an antitumor agent and open a new field of antiangiogenic therapy. PMID:24013228

  12. Curcumin inhibits anchorage-independent growth of HT29 human colon cancer cells by targeting epigenetic restoration of the tumor suppressor gene DLEC1

    PubMed Central

    Guo, Yue; Shu, Limin; Zhang, Chengyue; Su, Zheng-Yuan; Kong, Ah-Ng Tony

    2015-01-01

    Colorectal cancer remains the most prevalent malignancy in humans. The impact of epigenetic alterations on the development of this complex disease is now being recognized. The dynamic and reversible nature of epigenetic modifications makes them a promising target in colorectal cancer chemoprevention and treatment. Curcumin (CUR), the major component in Curcuma longa, has been shown as a potent chemopreventive phytochemical that modulates various signaling pathways. Deleted in lung and esophageal cancer 1 (DLEC1) is a tumor suppressor gene with reduced transcriptional activity and promoter hypermethylation in various cancers, including colorectal cancer. In the present study, we aimed to investigate the inhibitory role of DLEC1 in anchorage-independent growth of the human colorectal adenocarcinoma HT29 cells and epigenetic regulation by CUR. Specifically, we found that CUR treatment inhibited colony formation of HT29 cells, whereas stable knockdown of DLEC1 using lentiviral short hairpin RNA vector increased cell proliferation and colony formation. Knockdown of DLEC1 in HT29 cells attenuated the ability of CUR to inhibit anchorage-independent growth. Methylation-specific polymerase chain reaction (MSP), bisulfite genomic sequencing, and methylated DNA immunoprecipitation revealed that CUR decreased CpG methylation of the DLEC1 promoter in HT29 cells after 5 days of treatment, corresponding to increased mRNA expression of DLEC1. Furthermore, CUR decreased the protein expression of DNA methyltransferases and subtypes of histone deacetylases (HDAC4, 5, 6, and 8). Taken together, our results suggest that the inhibitory effect of CUR on anchorage-independent growth of HT29 cells could, at least in part, involve the epigenetic demethylation and up-regulation of DLEC1. PMID:25640947

  13. Citrus polymethoxylated flavone inhibition of tumor necrosis factor-alpha in LPS-challenged mice and human monocytes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus flavonoids have been investigated for their biological actions in animals, particularly for their anti-cancer effects, and for their cholesterol-lowering and anti-inflammatory properties. An investigation of the production of cytokines in bacterial lipopolysaccharide (LPS)-treated human mono...

  14. A polymeric nanoparticle formulation of curcumin in combination with sorafenib synergistically inhibits tumor growth and metastasis in an orthotopic model of human hepatocellular carcinoma.

    PubMed

    Hu, Bo; Sun, Ding; Sun, Chao; Sun, Yun-Fan; Sun, Hai-Xiang; Zhu, Qing-Feng; Yang, Xin-Rong; Gao, Ya-Bo; Tang, Wei-Guo; Fan, Jia; Maitra, Anirban; Anders, Robert A; Xu, Yang

    2015-12-25

    Curcumin, a yellow polyphenol extracted from the rhizome of turmeric root (Curcuma longa) has potent anti-cancer properties in many types of tumors with ability to reverse multidrug resistance of cancer cells. However, widespread clinical application of this agent in cancer and other diseases has been limited due to its poor aqueous solubility. The recent findings of polymeric nanoparticle formulation of curcumin (NFC) have shown the potential for circumventing the problem of poor solubility, however evidences for NFC's anti-cancer and reverse multidrug resistance properties are lacking. Here we provide models of human hepatocellular carcinoma (HCC), the most common form of primary liver cancer, in vitro and in vivo to evaluate the efficacy of NFC alone and in combination with sorafenib, a kinase inhibitor approved for treatment of HCC. Results showed that NFC not only inhibited the proliferation and invasion of HCC cell lines in vitro, but also drastically suppressed primary tumor growth and lung metastases in vivo. Moreover, in combination with sorafenib, NFC induced HCC cell apoptosis and cell cycle arrest. Mechanistically, NFC and sorafenib synergistically down-regulated the expression of MMP9 via NF-κB/p65 signaling pathway. Furthermore, the combination therapy significantly decreased the population of CD133-positive HCC cells, which have been reported as cancer initiating cells in HCC. Taken together, NanoCurcumin provides an opportunity to expand the clinical repertoire of this agent. Additional studies utilizing a combination of NanoCurcumin and sorafenib in HCC are needed for further clinical development. PMID:26482853

  15. Aromatase in the human choriocarcinoma JEG-3: inhibition by R 76 713 in cultured cells and in tumors grown in nude mice.

    PubMed

    Krekels, M D; Wouters, W; De Coster, R; Van Ginckel, R; Leonaers, A; Janssen, P A

    1991-04-01

    The aromatase enzyme and its inhibition by R 76 713 were characterized in the JEG-3 choriocarcinoma cell line in culture and in JEG-3 tumors grown in nude mice. Optimal cell culture parameters and enzyme reaction conditions for the determination of aromatase activity were established. Under these conditions, in vitro JEG-3 aromatase was inhibited by R 76 713 with IC50-values of 7.6 +/- 0.5 nM and 2.7 +/- 1.1 nM using 500 nM of androstenedione and testosterone as substrate respectively. The Km-value of the aromatase enzyme with androstenedione as substrate was 62 +/- 19 nM; with testosterone as substrate, a value of 166 +/- 27 nM was found. In the presence of increasing concentrations of R 76 713, the Km-values increased while the Vmax remained unchanged. Using androstenedione and testosterone as substrate Lineweaver-Burk analysis of the data showed Ki-values for R 76 713 of 0.43 +/- 0.06 nM and 0.47 +/- 0.39 nM respectively. R 76 713 appeared to competitively inhibit the JEG-3 aromatase. Aromatase could easily be measured in homogenates of JEG-3 tumors grown in nude mice and showed Km-values similar to those found for JEG-3 cells in vitro. IC50-values for inhibition of tumor aromatase by R 76 713 were also similar to those found in cultured cells. Tumor aromatase measured ex vivo, 2 h after a single oral administration of R 76 713 was dose-dependently inhibited. An ED50-value of 0.05 mg/kg was calculated. The JEG-3 choriocarcinoma proved to be a useful aromatase model enabling the comparative study of aromatase inhibition in vitro and in vivo. PMID:2031856

  16. p190RhoGAP can act to inhibit PDGF-induced gliomas in mice: a putative tumor suppressor encoded on human Chromosome 19q13.3

    PubMed Central

    Wolf, Rebecca M.; Draghi, Nicole; Liang, Xiquan; Dai, Chengkai; Uhrbom, Lene; Eklöf, Charlotta; Westermark, Bengt; Holland, Eric C.; Resh, Marilyn D.

    2003-01-01

    p190RhoGAP and Rho are key regulators of oligodendrocyte differentiation. The gene encoding p190RhoGAP is located at 19q13.3 of the human chromosome, a locus that is deleted in 50%–80% of oligodendrogliomas. Here we provide evidence that p190RhoGAP may suppress gliomagenesis by inducing a differentiated glial phenotype. Using a cell culture model of autocrine loop PDGF stimulation, we show that reduced Rho activity via p190RhoGAP overexpression or Rho kinase inhibition induced cellular process extension, a block in proliferation, and reduced expression of the neural precursor marker nestin. In vivo infection of mice with retrovirus expressing PDGF and the p190 GAP domain caused a decreased incidence of oligodendrogliomas compared with that observed with PDGF alone. Independent experiments revealed that the retroviral vector insertion site in 3 of 50 PDGF-induced gliomas was within the p190RhoGAP gene. This evidence strongly suggests that p190 regulates critical components of PDGF oncogenesis and can act as a tumor suppressor in PDGF-induced gliomas by down-regulating Rho activity. PMID:12600941

  17. Anandamide inhibits breast tumor-induced angiogenesis

    PubMed Central

    Picardi, P; Ciaglia, E; Proto, MC; Pisanti, S

    2014-01-01

    Breast cancer is one of the most frequently diagnosed malignancies and a leading cause of cancer death in women. Great advances in the treatment of primary tumors have led to a significant increment in the overall survival rates, however recurrence and metastatic disease, the underlying cause of death, are still a medical challenge. Breast cancer is highly dependent on neovascularization to progress. In the last years several anti-angiogenic drugs have been developed and administered to patients in combination with chemotherapeutic drugs. Collected preclinical evidence has proposed the endocannabinoid system as a potential target in cancer. The endocannabinoid anandamide has been reported to affect breast cancer growth at multiple levels, by inhibiting proliferation, migration and invasiveness in vitro and in vivo and by directly inhibiting angiogenesis. Aim of the present work is to investigate if anandamide is able to affect the proangiogenic phenotype of the highly invasive and metastatic breast cancer cells MDA-MB-231. We found that following anandamide treatment, MDAMB-231 cells lose their ability to stimulate endothelial cells proliferation in vitro, due to a significant inhibition of all the pro-angiogenic factors produced by these cells. This finding adds another piece of evidence to the anti-tumor efficacy of anandamide in breast cancer. PMID:25147760

  18. Dll4 Inhibition plus Aflibercept Markedly Reduces Ovarian Tumor Growth.

    PubMed

    Huang, Jie; Hu, Wei; Hu, Limin; Previs, Rebecca A; Dalton, Heather J; Yang, Xiao-Yun; Sun, Yunjie; McGuire, Michael; Rupaimoole, Rajesha; Nagaraja, Archana S; Kang, Yu; Liu, Tao; Nick, Alpa M; Jennings, Nicholas B; Coleman, Robert L; Jaffe, Robert B; Sood, Anil K

    2016-06-01

    Delta-like ligand 4 (Dll4), one of the Notch ligands, is overexpressed in ovarian cancer, especially in tumors resistant to anti-VEGF therapy. Here, we examined the biologic effects of dual anti-Dll4 and anti-VEGF therapy in ovarian cancer models. Using Dll4-Fc blockade and anti-Dll4 antibodies (murine REGN1035 and human REGN421), we evaluated the biologic effects of Dll4 inhibition combined with aflibercept or chemotherapy in orthotopic mouse models of ovarian cancer. We also examined potential mechanisms by which dual Dll4 and VEGF targeting inhibit tumor growth using immunohistochemical staining for apoptosis and proliferation markers. Reverse-phase protein arrays were used to identify potential downstream targets of Dll4 blockade. Dual targeting of VEGF and Dll4 with murine REGN1035 showed superior antitumor effects in ovarian cancer models compared with either monotherapy. In the A2780 model, REGN1035 (targets murine Dll4) or REGN421 (targets human Dll4) reduced tumor weights by 62% and 82%, respectively; aflibercept alone reduced tumor weights by 90%. Greater therapeutic effects were observed for Dll4 blockade (REGN1035) combined with either aflibercept or docetaxel (P < 0.05 for the combination vs. aflibercept). The superior antitumor effects of REGN1035 and aflibercept were related to increased apoptosis in tumor cells compared with the monotherapy. We also found that GATA3 expression was significantly increased in tumor stroma from the mice treated with REGN1035 combined with docetaxel or aflibercept, suggesting an indirect effect of these combination treatments on the tumor stroma. These findings identify that dual targeting of Dll4 and VEGF is an attractive therapeutic approach. Mol Cancer Ther; 15(6); 1344-52. ©2016 AACR. PMID:27009216

  19. Inhibition of TGFBIp expression reduces lymphangiogenesis and tumor metastasis.

    PubMed

    Maeng, Y-S; Aguilar, B; Choi, S-I; Kim, E K

    2016-01-14

    Transforming growth factor-β-induced protein (TGFBIp) is an extracellular matrix protein that has a role in a wide range of pathological conditions. However, the role of TGFBIp signaling in lymphangiogenesis is poorly understood. The purpose of this study was therefore to analyze the effects of TGFBIp on lymphangiogenesis and determine whether TGFBIp-related lymphangiogenesis is important for the metastasis of tumor cells. TGFBIp increased adhesion, migration, and morphologic differentiation of human lymphatic endothelial cells (LECs), consistent with an increase in lymphatic vessel sprouting in a three-dimensional lymphatic ring assay. TGFBIp also induced phosphorylation of intracellular signaling molecules SRC, FAK, AKT, JNK and ERK. TGFBIp-induced lymphatic vessel sprouting was inhibited by addition of anti-integrin β3 antibody and pharmacologic inhibitors of FAK, AKT, JNK or ERK. TGFBIp increased both CCL21 expression in LECs, a chemokine that actively recruits tumor cells expressing the cognate chemokine receptors to lymphatic vessels and LEC permeability by inducing the dissociation of VE-cadherin junctions between LECs via the activation of SRC signaling. In vivo, inhibition of TGFBIp expression in SW620 cancer cells dramatically reduced tumor lymphangiogenesis and metastasis. Collectively, our findings demonstrate that TGFBIp is a lymphangiogenic factor contributing to tumor dissemination and represents a potential target to inhibit metastasis. PMID:25772247

  20. Scopoletin, an active principle of tree tobacco (Nicotiana glauca) inhibits human tumor vascularization in xenograft models and modulates ERK1, VEGF-A, and FGF-2 in computer model.

    PubMed

    Tabana, Yasser M; Hassan, Loiy Elsir A; Ahamed, Mohamed B Khadeer; Dahham, Saad S; Iqbal, Muhammad Adnan; Saeed, Mohammed A A; Khan, Md Shamsuddin S; Sandai, Doblin; Majid, Aman S Abdul; Oon, Chern Ein; Majid, Amin Malik S A

    2016-09-01

    We recently reported the antineovascularization effect of scopoletin on rat aorta and identified its potential anti-angiogenic activity. Scopoletin could be useful as a systemic chemotherapeutic agent against angiogenesis-dependent malignancies if its antitumorigenic activity is investigated and scientifically proven using a suitable human tumor xenograft model. In the present study, bioassay-guided (anti-angiogenesis) phytochemical investigation was conducted on Nicotiana glauca extract which led to the isolation of scopoletin. Further, anti-angiogenic activity of scopoletin was characterized using ex vivo, in vivo and in silico angiogenesis models. Finally, the antitumorigenic efficacy of scopoletin was studied in human colorectal tumor xenograft model using athymic nude mice. For the first time, an in vivo anticancer activity of scopoletin was reported and characterized using xenograft models. Scopoletin caused significant suppression of sprouting of microvessels in rat aortic explants with IC50 (median inhibitory concentration) 0.06μM. Scopoletin (100 and 200mg/kg) strongly inhibited (59.72 and 89.4%, respectively) vascularization in matrigel plugs implanted in nude mice. In the tumor xenograft model, scopoletin showed remarkable inhibition on tumor growth (34.2 and 94.7% at 100 and 200mg/kg, respectively). Tumor histology revealed drastic reduction of the extent of vascularization. Further, immunostaining of CD31 and NG2 receptors in the histological sections confirmed the antivascular effect of scopoletin in tumor vasculature. In computer modeling, scopoletin showed strong ligand affinity and binding energies toward the following angiogenic factors: protein kinase (ERK1), vascular endothelial growth factor A (VEGF-A), and fibroblast growth factor 2 (FGF-2). These results suggest that the antitumor activity of scopoletin may be due to its strong anti-angiogenic effect, which may be mediated by its effective inhibition of ERK1, VEGF-A, and FGF-2. PMID:27133199

  1. PI3K/AKT/mTOR and sonic hedgehog pathways cooperate together to inhibit human pancreatic cancer stem cell characteristics and tumor growth

    PubMed Central

    Sharma, Narinder; Nanta, Rajesh; Sharma, Jay; Gunewardena, Sumedha; Singh, Karan P.; Shankar, Sharmila; Srivastava, Rakesh K.

    2015-01-01

    Cancer stem cells (CSCs) play major roles in cancer initiation, progression, and metastasis. It is evident from growing reports that PI3K/Akt/mTOR and Sonic Hedgehog (Shh) signaling pathways are aberrantly reactivated in pancreatic CSCs. Here, we examined the efficacy of combining NVP-LDE-225 (PI3K/mTOR inhibitor) and NVP-BEZ-235 (Smoothened inhibitor) on pancreatic CSCs characteristics, microRNA regulatory network, and tumor growth. NVP-LDE-225 co-operated with NVP-BEZ-235 in inhibiting pancreatic CSC's characteristics and tumor growth in mice by acting at the level of Gli. Combination of NVP-LDE-225 and NVP-BEZ-235 inhibited self-renewal capacity of CSCs by suppressing the expression of pluripotency maintaining factors Nanog, Oct-4, Sox-2 and c-Myc, and transcription of Gli. NVP-LDE-225 co-operated with NVP-BEZ-235 to inhibit Lin28/Let7a/Kras axis in pancreatic CSCs. Furthermore, a superior interaction of these drugs was observed on spheroid formation by pancreatic CSCs isolated from Pankras/p53 mice. The combination of these drugs also showed superior effects on the expression of proteins involved in cell proliferation, survival and apoptosis. In addition, NVP-LDE-225 co-operated with NVP-BEZ-235 in inhibiting EMT through modulation of cadherin, vimentin and transcription factors Snail, Slug and Zeb1. In conclusion, these data suggest that the combined inhibition of PI3K/Akt/mTOR and Shh pathways may be beneficial for the treatment of pancreatic cancer. PMID:26451606

  2. Netrin-4 delays colorectal cancer carcinomatosis by inhibiting tumor angiogenesis.

    PubMed

    Eveno, Clarisse; Broqueres-You, Dong; Feron, Jean-Guillaume; Rampanou, Aurore; Tijeras-Raballand, Annemilaï; Ropert, Stanislas; Leconte, Laurence; Levy, Bernard I; Pocard, Marc

    2011-04-01

    A close relationship between tumor angiogenesis, growth, and carcinomatosis has been observed. Netrin-4 (NT-4) has been shown to regulate angiogenic responses. We aimed to examine the effects of NT-4 on colon tumor angiogenesis, growth, and carcinomatosis. We showed that NT-4 was expressed in human colon cancer cells (LS174). A 20-fold increase in NT-4 expression was stably induced by NT-4 pcDNA in LS174 cells. In vivo, a Matrigel angiogenesis assay showed that NT-4 overexpression altered vascular endothelial growth factor (VEGF)/basic fibroblast growth factor-induced angiogenesis. In nude mice with LS174 xenografts, NT-4 overexpression inhibited tumor angiogenesis and growth. In addition, these NT-4-involved inhibitory effects were associated with decreased tumor cell proliferation and increased tumor cell apoptosis. Using an orthotopic peritoneal carcinomatosis model, we demonstrated that NT-4 overexpression decreased colorectal cancer carcinomatosis. Moreover, carcinomatosis-related ascites formation was significantly decreased in mice transplanted with NT-4 LS174 cells versus control LS174 cells. The antiangiogenic activity of NT-4 was probably mediated by binding to its receptor neogenin. Netrin-4 had a direct effect on neither in vitro apoptosis and proliferation of cultured LS174 cells nor the VEGF-induced acute increase in vascular permeability in vivo. We propose that NT-4 overexpression decreases tumor growth and carcinomatosis, probably via an antiangiogenic effect, underlying the potential therapeutic interest in NT-4 in the treatment of colorectal cancer growth and carcinomatosis. PMID:21406174

  3. RSUME inhibits VHL and regulates its tumor suppressor function.

    PubMed

    Gerez, J; Tedesco, L; Bonfiglio, J J; Fuertes, M; Barontini, M; Silberstein, S; Wu, Y; Renner, U; Páez-Pereda, M; Holsboer, F; Stalla, G K; Arzt, E

    2015-09-10

    Somatic mutations or loss of von Hippel-Lindau (pVHL) happen in the majority of VHL disease tumors, which present a constitutively active Hypoxia Inducible Factor (HIF), essential for tumor growth. Recently described mechanisms for pVHL modulation shed light on the open question of the HIF/pVHL pathway regulation. The aim of the present study was to determine the molecular mechanism by which RSUME stabilizes HIFs, by studying RSUME effect on pVHL function and to determine the role of RSUME on pVHL-related tumor progression. We determined that RSUME sumoylates and physically interacts with pVHL and negatively regulates the assembly of the complex between pVHL, Elongins and Cullins (ECV), inhibiting HIF-1 and 2α ubiquitination and degradation. We found that RSUME is expressed in human VHL tumors (renal clear-cell carcinoma (RCC), pheochromocytoma and hemangioblastoma) and by overexpressing or silencing RSUME in a pVHL-HIF-oxygen-dependent degradation stability reporter assay, we determined that RSUME is necessary for the loss of function of type 2 pVHL mutants. The functional RSUME/pVHL interaction in VHL-related tumor progression was further confirmed using a xenograft assay in nude mice. RCC clones, in which RSUME was knocked down and express either pVHL wt or type 2 mutation, have an impaired tumor growth, as well as HIF-2α, vascular endothelial growth factor A and tumor vascularization diminution. This work shows a novel mechanism for VHL tumor progression and presents a new mechanism and factor for targeting tumor-related pathologies with pVHL/HIF altered function. PMID:25500545

  4. The p53 target gene desmocollin 3 acts as a novel tumor suppressor through inhibiting EGFR/ERK pathway in human lung cancer.

    PubMed

    Cui, Tiantian; Chen, Yuan; Yang, Linlin; Knösel, Thomas; Huber, Otmar; Pacyna-Gengelbach, Manuela; Petersen, Iver

    2012-12-01

    Desmosomes are intercellular junctions that confer strong cell-cell adhesion. Altered expression of desmocollin 3 (DSC3), a member of the desmosomal cadherin family, was found in various cancers; however, its functional involvement in carcinogenesis has not yet been elucidated. Expression/localization of DSC3 was analyzed by real-time reverse transcription-PCR, western blotting, immunofluorescence and immunohistochemistry. Methylation status of DSC3 was examined by demethylation tests, methylation-specific PCR and bisulfite sequencing. It turned out that downregulation of DSC3 in lung cancer cells was associated with DNA hypermethylation. In primary lung tumors, DSC3 was a potential diagnostic marker for lung squamous cell carcinoma, and DSC3 DNA hypermethylation was correlated with poor clinical outcome. To investigate the effect of the tumor suppressor gene p53 on DSC3, transient transfection with a wild-type p53-expression vector was performed. Overexpression of p53 resulted in an increased expression of DSC3 in a DSC3-unmethylated lung cancer cell line H2170, but not in H1299, a DSC3-methylated cell line. However, combination of p53 transfection with demethylation agent 5-aza-2'-deoxycytidine treatment led to increased expression of DSC3 in H1299 cells. Furthermore, functional studies after stable transfection of a DSC3 expression vector showed that ectopic expression of DSC3 inhibited cell proliferation, anchorage-independent growth, migration, as well as invasion, and most interestingly led to reduced phosphorylation levels of extracellular signal-regulated kinase1/2. Taken together, our data suggested that DSC3 acts as a novel tumor suppressor gene through inhibition of epidermal growth factor receptor/extracellular signal-regulated kinase signaling in lung cancer cells. PMID:22941060

  5. Inhibition of Human Colon Cancer Growth by Antibody-Directed Human LAK Cells in SCID Mice

    NASA Astrophysics Data System (ADS)

    Takahashi, Hiroshi; Nakada, Tetsuya; Puisieux, Isabelle

    1993-03-01

    Advanced human colon cancer does not respond to lymphokine-activated killer (LAK) cells. In order to direct cytotoxic cells to the tumor, human LAK cells linked with antibodies to a tumor cell surface antigen were tested with established hepatic metastases in severe combined immunodeficient (SCID) mice. These cells had increased uptake into the tumor and suppression of tumor growth as compared with LAK cells alone, thereby improving the survival of tumor-bearing mice. Thus, tumor growth can be inhibited by targeted LAK cells, and SCID mice can be used to test the antitumor properties of human effector cells.

  6. Dioscin inhibits colon tumor growth and tumor angiogenesis through regulating VEGFR2 and AKT/MAPK signaling pathways

    SciTech Connect

    Tong, Qingyi; Qing, Yong; Wu, Yang; Hu, Xiaojuan; Jiang, Lei; Wu, Xiaohua

    2014-12-01

    Dioscin has shown cytotoxicity against cancer cells, but its in vivo effects and the mechanisms have not elucidated yet. The purpose of the current study was to assess the antitumor effects and the molecular mechanisms of dioscin. We showed that dioscin could inhibit tumor growth in vivo and has no toxicity at the test condition. The growth suppression was accompanied by obvious blood vessel decrease within solid tumors. We also found dioscin treatment inhibited the proliferation of cancer and endothelial cell lines, and most sensitive to primary cultured human umbilical vein endothelial cells (HUVECs). What's more, analysis of HUVECs migration, invasion, and tube formation exhibited that dioscin has significantly inhibitive effects to these actions. Further analysis of blood vessel formation in the matrigel plugs indicated that dioscin could inhibit VEGF-induced blood vessel formation in vivo. We also identified that dioscin could suppress the downstream protein kinases of VEGFR2, including Src, FAK, AKT and Erk1/2, accompanied by the increase of phosphorylated P38MAPK. The results potently suggest that dioscin may be a potential anticancer drug, which efficiently inhibits angiogenesis induced by VEGFR2 signaling pathway as well as AKT/MAPK pathways. - Highlights: • Dioscin inhibits tumor growth in vivo and does not exhibit any toxicity. • Dioscin inhibits angiogenesis within solid tumors. • Dioscin inhibits the proliferation, migration, invasion, and tube formation of HUVECs. • Dioscin inhibits VEGF–induced blood vessel formation in vivo. • Dioscin inhibits VEGFR2 signaling pathway as well as AKT/MAPK pathway.

  7. Inhibition of tumor cell proliferation and motility by fibroblasts is both contact and soluble factor dependent

    PubMed Central

    Alkasalias, Twana; Flaberg, Emilie; Kashuba, Vladimir; Alexeyenko, Andrey; Pavlova, Tatiana; Savchenko, Andrii; Szekely, Laszlo; Klein, George; Guven, Hayrettin

    2014-01-01

    Normal human and murine fibroblasts can inhibit proliferation of tumor cells when cocultured in vitro. The inhibitory capacity varies depending on the donor and the site of origin of the fibroblast. We showed previously that effective inhibition requires formation of a morphologically intact fibroblast monolayer before seeding of the tumor cells. Here we show that inhibition is extended to motility of tumor cells and we dissect the factors responsible for these inhibitory functions. We find that inhibition is due to two different sets of molecules: (i) the extracellular matrix (ECM) and other surface proteins of the fibroblasts, which are responsible for contact-dependent inhibition of tumor cell proliferation; and (ii) soluble factors secreted by fibroblasts when confronted with tumor cells (confronted conditioned media, CCM) contribute to inhibition of tumor cell proliferation and motility. However, conditioned media (CM) obtained from fibroblasts alone (nonconfronted conditioned media, NCM) did not inhibit tumor cell proliferation and motility. In addition, quantitative PCR (Q-PCR) data show up-regulation of proinflammatory genes. Moreover, comparison of CCM and NCM with an antibody array for 507 different soluble human proteins revealed differential expression of growth differentiation factor 15, dickkopf-related protein 1, endothelial-monocyte-activating polypeptide II, ectodysplasin A2, Galectin-3, chemokine (C-X-C motif) ligand 2, Nidogen1, urokinase, and matrix metalloproteinase 3. PMID:25404301

  8. Inhibition Effect of a Custom Peptide on Lung Tumors

    PubMed Central

    Huang, Chih-Yu; Huang, Hsuan-Yu; Forrest, Michael D.; Pan, Yun-Ru; Wu, Wei-Jen; Chen, Hueih-Min

    2014-01-01

    Cecropin B is a natural antimicrobial peptide and CB1a is a custom, engineered modification of it. In vitro, CB1a can kill lung cancer cells at concentrations that do not kill normal lung cells. Furthermore, in vitro, CB1a can disrupt cancer cells from adhering together to form tumor-like spheroids. Mice were xenografted with human lung cancer cells; CB1a could significantly inhibit the growth of tumors in this in vivo model. Docetaxel is a drug in present clinical use against lung cancers; it can have serious side effects because its toxicity is not sufficiently limited to cancer cells. In our studies in mice: CB1a is more toxic to cancer cells than docetaxel, but dramatically less toxic to healthy cells. PMID:25310698

  9. Tetrahydro Iso-Alpha Acids and Hexahydro Iso-Alpha Acids from Hops Inhibit Proliferation of Human Hepatocarcinoma Cell Lines and Reduce Diethylnitrosamine Induced Liver Tumor Formation in Rats.

    PubMed

    Stärkel, Peter; De Saeger, Christine; Delire, Bénédicte; Magat, Julie; Jordan, Bénédicte; Konda, Veera R; Tripp, Mathew L; Borbath, Ivan

    2015-01-01

    Chronic inflammation plays important role in the pathogenesis of hepatocellular carcinoma (HCC). To date, no antiinflammatory approach has shown its efficacy in preventing HCC occurrence in humans. Because tetra- and hexahydro isoalpha acids (THIAA and HHIAA) from hops elicit antiinflammatory properties, we evaluated these compounds for antitumor effects in vitro in human HCC cell lines (HepG2, Hep3B, Huh7) and in vivo in diethylnitrosamine (DEN)-induced animal model of HCC. In human HCC cell lines, THIAA and HHIAA reduced cell proliferation and viability which was associated with the inhibition of the NF-κB-DNA binding and tumor necrosis factor α mRNA expression. Both compounds also inhibited phosphorylation of the mTOR effector p70S6 kinase without affecting ERK, AKT, JNK, and GSK3β phosphorylation or activator protein-1 activation. In DEN-treated rats, administration of THIAA and HHIAA in food reduced the tumor numbers and the expression of the cellular transformation marker glutathione-S-transferase in the liver. In conclusion, THIAA and HHIAA show antitumor properties in vitro in human HCC cell lines as well as in vivo in a chemically induced animal model of HCC. PMID:25941903

  10. α-santalol inhibits the angiogenesis and growth of human prostate tumor growth by targeting vascular endothelial growth factor receptor 2-mediated AKT/mTOR/P70S6K signaling pathway

    PubMed Central

    2013-01-01

    Background VEGF receptor 2 (VEGFR2) inhibitors, as efficient antiangiogenesis agents, have been applied in the cancer treatment. However, recently, most of these anticancer drugs have some adverse effects. Discovery of novel VEGFR2 inhibitors as anticancer drug candidates is still needed. Methods We used α-santalol and analyzed its inhibitory effects on human umbilical vein endothelial cells (HUVECs) and Prostate tumor cells (PC-3 or LNCaP) in vitro. Tumor xenografts in nude mice were used to examine the in vivo activity of α-santalol. Results α-santalol significantly inhibits HUVEC proliferation, migration, invasion, and tube formation. Western blot analysis indicated that α-santalol inhibited VEGF-induced phosphorylation of VEGFR2 kinase and the downstream protein kinases including AKT, ERK, FAK, Src, mTOR, and pS6K in HUVEC, PC-3 and LNCaP cells. α-santalol treatment inhibited ex vivo and in vivo angiogenesis as evident by rat aortic and sponge implant angiogenesis assay. α-santalol significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model. The antiangiogenic effect by CD31 immunohistochemical staining indicated that α-santalol inhibited tumorigenesis by targeting angiogenesis. Furthermore, α-santalol reduced the cell viability and induced apoptosis in PC-3 cells, which were correlated with the downregulation of AKT, mTOR and P70S6K expressions. Molecular docking simulation indicated that α-santalol form hydrogen bonds and aromatic interactions within the ATP-binding region of the VEGFR2 kinase unit. Conclusion α-santalol inhibits angiogenesis by targeting VEGFR2 regulated AKT/mTOR/P70S6K signaling pathway, and could be used as a potential drug candidate for cancer therapy. PMID:24261856

  11. AIF inhibits tumor metastasis by protecting PTEN from oxidation

    PubMed Central

    Shen, Shao-Ming; Guo, Meng; Xiong, Zhong; Yu, Yun; Zhao, Xu-Yun; Zhang, Fei-Fei; Chen, Guo-Qiang

    2015-01-01

    Apoptosis-inducing factor (AIF) exerts dual roles on cell death and survival, but its substrates as a putative oxidoreductase and roles in tumorigenesis remain elusive. Here, we report that AIF physically interacts with and inhibits the oxidation of phosphatase and tensin homolog on chromosome ten (PTEN), a tumor suppressor susceptible for oxidation-mediated inactivation. More intriguingly, we also identify PTEN as a mitochondrial protein and the ectopic expression of mitochondrial targeting sequence-carrying PTEN almost completely inhibits Akt phosphorylation in PTEN-deficient cells. AIF knockdown causes oxidation-mediated inactivation of the lipid phosphatase activity of PTEN, with ensuing activation of Akt kinase, phosphorylation of the Akt substrate GSK-3β, and activation of β-catenin signaling in cancer cells. Through its effect on β-catenin signaling, AIF inhibits epithelial–mesenchymal transition (EMT) and metastasis of cancer cells in vitro and in orthotopically implanted xenografts. Accordingly, the expression of AIF is correlated with the survival of human patients with cancers of multiple origins. These results identify PTEN as the substrate of AIF oxidoreductase and reveal a novel function for AIF in controlling tumor metastasis. PMID:26415504

  12. Knockdown of astrocyte elevated gene-1 inhibits tumor growth and modifies microRNAs expression profiles in human colorectal cancer cells

    SciTech Connect

    Huang, Sujun; Wu, Binwen; Li, Dongfeng; Zhou, Weihong; Deng, Gang; Zhang, Kaijun; Li, Youjia

    2014-02-14

    Highlights: • AEG-1 expression in CRC cell lines and down-regulation or upregulation of AEG-1 in vitro. • Knockdown of AEG-1 inhibits cell proliferation, colony formation and invasion. • Upregulation of AEG-1 enhances proliferation, invasion and colony formation. • Knockdown of AEG-1 accumulates G0/G1-phase cells and promotes apoptosis in CRC cells. • AEG-1 knockdown increases 5-FU cytotoxicity. - Abstract: Astrocyte elevated gene-1 (AEG-1), upregulated in various types of malignancies including colorectal cancer (CRC), has been reported to be associated with the carcinogenesis. MicroRNAs (miRNAs) are widely involved in the initiation and progression of cancer. However, the functional significance of AEG-1 and the relationship between AEG-1 and microRNAs in human CRC remains unclear. The aim of this study was to investigate whether AEG-1 could serve as a potential therapeutic target of human CRC and its possible mechanism. We adopted a strategy of ectopic overexpression or RNA interference to upregulate or downregulate expression of AEG-1 in CRC models. Their phenotypic changes were analyzed by Western blot, MTT and transwell matrix penetration assays. MicroRNAs expression profiles were performed using microarray analysis followed by validation using qRT-PCR. Knockdown of AEG-1 could significantly inhibit colon cancer cell proliferation, colony formation, invasion and promotes apoptosis. Conversely, upregulation of AEG-1 could significantly enhance cell proliferation, invasion and reduced apoptisis. AEG-1 directly contributes to resistance to chemotherapeutic drug. Targeted downregulation of AEG-1 might improve the expression of miR-181a-2{sup ∗}, -193b and -193a, and inversely inhibit miR-31 and -9{sup ∗}. Targeted inhibition of AEG-1 can lead to modification of key elemental characteristics, such as miRNAs, which may become a potential effective therapeutic strategy for CRC.

  13. Isoliquiritigenin Induces Apoptosis and Inhibits Xenograft Tumor Growth of Human Lung Cancer Cells by Targeting Both Wild Type and L858R/T790M Mutant EGFR*

    PubMed Central

    Jung, Sung Keun; Lee, Mee-Hyun; Lim, Do Young; Kim, Jong Eun; Singh, Puja; Lee, Sung-Young; Jeong, Chul-Ho; Lim, Tae-Gyu; Chen, Hanyong; Chi, Young-In; Kundu, Joydeb Kumar; Lee, Nam Hyouck; Lee, Charles C.; Cho, Yong-Yeon; Bode, Ann M.; Lee, Ki Won; Dong, Zigang

    2014-01-01

    Non-small-cell lung cancer (NSCLC) is associated with diverse genetic alterations including mutation of epidermal growth factor receptor (EGFR). Isoliquiritigenin (ILQ), a chalcone derivative, possesses anticancer activities. In the present study, we investigated the effects of ILQ on the growth of tyrosine kinase inhibitor (TKI)-sensitive and -resistant NSCLC cells and elucidated its underlying mechanisms. Treatment with ILQ inhibited growth and induced apoptosis in both TKI-sensitive and -resistant NSCLC cells. ILQ-induced apoptosis was associated with the cleavage of caspase-3 and poly-(ADP-ribose)-polymerase, increased expression of Bim, and reduced expression of Bcl-2. In vitro kinase assay results revealed that ILQ inhibited the catalytic activity of both wild type and double mutant (L858R/T790M) EGFR. Treatment with ILQ inhibited the anchorage-independent growth of NIH3T3 cells stably transfected with either wild type or double-mutant EGFR with or without EGF stimulation. ILQ also reduced the phosphorylation of Akt and ERK1/2 in both TKI-sensitive and -resistant NSCLC cells, and attenuated the kinase activity of Akt1 and ERK2 in vitro. ILQ directly interacted with both wild type and double-mutant EGFR in an ATP-competitive manner. A docking model study showed that ILQ formed two hydrogen bonds (Glu-762 and Met-793) with wild type EGFR and three hydrogen bonds (Lys-745, Met-793, and Asp-855) with mutant EGFR. ILQ attenuated the xenograft tumor growth of H1975 cells, which was associated with decreased expression of Ki-67 and diminished phosphorylation of Akt and ERK1/2. Taken together, ILQ suppresses NSCLC cell growth by directly targeting wild type or mutant EGFR. PMID:25368326

  14. Vitamin E metabolite 13'-carboxychromanols inhibit pro-inflammatory enzymes, induce apoptosis and autophagy in human cancer cells by modulating sphingolipids and suppress colon tumor development in mice.

    PubMed

    Jang, Yumi; Park, Na-Young; Rostgaard-Hansen, Agnetha Linn; Huang, Jianjie; Jiang, Qing

    2016-06-01

    Vitamin E forms are substantially metabolized to various carboxychromanols including 13'-carboxychromanols (13'-COOHs) that are found at high levels in feces. However, there is limited knowledge about functions of these metabolites. Here we studied δT-13'-COOH and δTE-13'-COOH, which are metabolites of δ-tocopherol and δ-tocotrienol, respectively. δTE-13'-COOH is also a natural constituent of a traditional medicine Garcinia Kola. Both 13'-COOHs are much stronger than tocopherols in inhibition of pro-inflammatory and cancer promoting cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX), and in induction of apoptosis and autophagy in colon cancer cells. The anticancer effects by 13'-COOHs appeared to be partially independent of inhibition of COX-2/5-LOX. Using liquid chromatography tandem mass spectrometry, we found that 13'-COOHs increased intracellular dihydrosphingosine and dihydroceramides after short-time incubation in HCT-116 cells, and enhanced ceramides while decreased sphingomyelins during prolonged treatment. Modulation of sphingolipids by 13'-COOHs was observed prior to or coinciding with biochemical manifestation of cell death. Pharmaceutically blocking the increase of these sphingolipids partially counteracted 13'-COOH-induced cell death. Further, 13'-COOH inhibited dihydroceramide desaturase without affecting the protein expression. In agreement with these mechanistic findings, δTE-13'-COOH significantly suppressed the growth and multiplicity of colon tumor in mice. Our study demonstrates that 13'-COOHs have anti-inflammatory and anticancer activities, may contribute to in vivo anticancer effect of vitamin E forms and are promising novel cancer prevention agents. PMID:27016075

  15. Inhibition of IL-17A in tumor microenvironment augments cytotoxicity of tumor-infiltrating lymphocytes in tumor-bearing mice.

    PubMed

    Hayata, Keiji; Iwahashi, Makoto; Ojima, Toshiyasu; Katsuda, Masahiro; Iida, Takeshi; Nakamori, Mikihito; Ueda, Kentaro; Nakamura, Masaki; Miyazawa, Motoki; Tsuji, Toshiaki; Yamaue, Hiroki

    2013-01-01

    It remains controversial whether IL-17A promotes or inhibits cancer progression. We hypothesized that IL-17A that is locally produced in the tumor microenvironment has an important role in angiogenesis and tumor immunity. We investigated the effect of inhibiting IL-17A at tumor sites on tumor growth and on local and systemic anti-tumor immunity. MC38 or B16 cells were inoculated subcutaneously into mice, and intratumoral injection of an adenovirus vector expressing siRNA against the mouse IL-17A gene (Ad-si-IL-17) significantly inhibited tumor growth in both tumor models compared with control mice. Inhibition of IL-17A at tumor sites significantly suppressed CD31, MMP9, and VEGF expression in tumor tissue. The cytotoxic activity of CD8(+) T cells from tumor-infiltrating lymphocytes in mice treated with Ad-si-IL-17 was significantly higher than in control mice; however, CD8(+) T cells from splenocytes had similar activity levels. Suppression of IL-17A at tumor sites led to a Th1-dominant environment, and moreover, eliminated myeloid-derived suppressor cells and regulatory T cells at tumor sites but not in splenocytes. In conclusion, blockade of IL-17A at tumor sites helped suppress tumor growth by inhibiting angiogenesis as well as cytotoxic T lymphocytes activation at tumor sites. PMID:23372655

  16. Decorin: A Growth Factor Antagonist for Tumor Growth Inhibition

    PubMed Central

    Järvinen, Tero A. H.; Prince, Stuart

    2015-01-01

    Decorin (DCN) is the best characterized member of the extracellular small leucine-rich proteoglycan family present in connective tissues, typically in association with or “decorating” collagen fibrils. It has substantial interest to clinical medicine owing to its antifibrotic, anti-inflammatory, and anticancer effects. Studies on DCN knockout mice have established that a lack of DCN is permissive for tumor development and it is regarded as a tumor suppressor gene. A reduced expression or a total disappearance of DCN has been reported to take place in various forms of human cancers during tumor progression. Furthermore, when used as a therapeutic molecule, DCN has been shown to inhibit tumor progression and metastases in experimental cancer models. DCN affects the biology of various types of cancer by targeting a number of crucial signaling molecules involved in cell growth, survival, metastasis, and angiogenesis. The active sites for the neutralization of different growth factors all reside in different parts of the DCN molecule. An emerging concept that multiple proteases, especially those produced by inflammatory cells, are capable of cleaving DCN suggests that native DCN could be inactivated in a number of pathological inflammatory conditions. In this paper, we review the role of DCN in cancer. PMID:26697491

  17. Clodronate inhibits tumor angiogenesis in mouse models of ovarian cancer

    PubMed Central

    Reusser, Nicole M; Dalton, Heather J; Pradeep, Sunila; Gonzalez-Villasana, Vianey; Jennings, Nicholas B; Vasquez, Hernan G; Wen, Yunfei; Rupaimoole, Rajesh; Nagaraja, Archana S; Gharpure, Kshipra; Miyake, Takahito; Huang, Jie; Hu, Wei; Lopez-Berestein, Gabriel; Sood, Anil K

    2014-01-01

    Purpose Bisphosphonates have been shown to inhibit and deplete macrophages. The effects of bisphosphonates on other cell types in the tumor microenvironment have been insufficiently studied. Here, we sought to determine the effects of bisphosphonates on ovarian cancer angiogenesis and growth via their effect on the microenvironment, including macrophage, endothelial and tumor cell populations. Experimental Design Using in vitro and in vivo models, we examined the effects of clodronate on angiogenesis and macrophage density, and the overall effect of clodronate on tumor size and metastasis. Results Clodronate inhibited the secretion of pro-angiogenic cytokines by endothelial cells and macrophages, and decreased endothelial migration and capillary tube formation. In treated mice, clodronate significantly decreased tumor size, number of tumor nodules, number of tumor-associated macrophages and tumor capillary density. Conclusions Clodronate is a potent inhibitor of tumor angiogenesis. These results highlight clodronate as a potential therapeutic for cancer. PMID:24841852

  18. Antibody mediated therapy targeting CD47 inhibits tumor progression of hepatocellular carcinoma.

    PubMed

    Xiao, Zhenyu; Chung, Haniee; Banan, Babak; Manning, Pamela T; Ott, Katherine C; Lin, Shin; Capoccia, Benjamin J; Subramanian, Vijay; Hiebsch, Ronald R; Upadhya, Gundumi A; Mohanakumar, Thalachallour; Frazier, William A; Lin, Yiing; Chapman, William C

    2015-05-01

    Human hepatocellular carcinoma (HCC) has a high rate of tumor recurrence and metastasis, resulting in shortened survival times. The efficacy of current systemic therapies for HCC is limited. In this study, we used xenograft tumor models to investigate the use of antibodies that block CD47 and inhibit HCC tumor growth. Immunostaining of tumor tissue and HCC cell lines demonstrated CD47 over-expression in HCC as compared to normal hepatocytes. Macrophage phagocytosis of HCC cells was increased after treatment with CD47 antibodies (CD47mAbs) that block CD47 binding to SIRPα. Further, CD47 blockade inhibited tumor growth in both heterotopic and orthotopic models of HCC, and promoted the migration of macrophages into the tumor mass. Our results demonstrate that targeting CD47 by specific antibodies has potential immunotherapeutic efficacy in human HCC. PMID:25721088

  19. Antibody mediated therapy targeting CD47 inhibits tumor progression of hepatocellular carcinoma

    PubMed Central

    Xiao, Zhenyu; Chung, Haniee; Banan, Babak; Manning, Pamela T.; Ott, Katherine C.; Lin, Shin; Capoccia, Benjamin J.; Subramanian, Vijay; Hiebsch, Ronald R.; Upadhya, Gundumi A.; Mohanakumar, Thalachallour; Frazier, William A.; Lin, Yiing; Chapman, William C.

    2016-01-01

    Human hepatocellular carcinoma (HCC) has a high rate of tumor recurrence and metastasis, resulting in shortened survival times. The efficacy of current systemic therapies for HCC is limited. In this study, we used xenograft tumor models to investigate the use of antibodies that block CD47 and inhibit HCC tumor growth. Immunostaining of tumor tissue and HCC cell lines demonstrated CD47 over-expression in HCC as compared to normal hepatocytes. Macrophage phagocytosis of HCC cells was increased after treatment with CD47 antibodies (CD47mAbs) that block CD47 binding to SIRPα. Further, CD47 blockade inhibited tumor growth in both heterotopic and orthotopic models of HCC, and promoted the migration of macrophages into the tumor mass. Our results demonstrate that targeting CD47 by specific antibodies has potential immunotherapeutic efficacy in human HCC. PMID:25721088

  20. Green tea polyphenol epigallocatechin-3-gallate inhibits advanced glycation end product-induced expression of tumor necrosis factor-α and matrix metalloproteinase-13 in human chondrocytes

    PubMed Central

    Rasheed, Zafar; Anbazhagan, Arivarasu N; Akhtar, Nahid; Ramamurthy, Sangeetha; Voss, Frank R; Haqqi, Tariq M

    2009-01-01

    Introduction The major risk factor for osteoarthritis (OA) is aging, but the mechanisms underlying this risk are only partly understood. Age-related accumulation of advanced glycation end products (AGEs) can activate chondrocytes and induce the production of proinflammatory cytokines and matrix metalloproteinases (MMPs). In the present study, we examined the effect of epigallocatechin-3-gallate (EGCG) on AGE-modified-BSA (AGE-BSA)-induced activation and production of TNFα and MMP-13 in human OA chondrocytes. Methods Human chondrocytes were derived from OA cartilage by enzymatic digestion and stimulated with in vitro-generated AGE-BSA. Gene expression of TNFα and MMP-13 was measured by quantitative RT-PCR. TNFα protein in culture medium was determined using cytokine-specific ELISA. Western immunoblotting was used to analyze the MMP-13 production in the culture medium, phosphorylation of mitogen-activated protein kinases (MAPKs), and the activation of NF-κB. DNA binding activity of NF-κB p65 was determined using a highly sensitive and specific ELISA. IκB kinase (IKK) activity was determined using an in vitro kinase activity assay. MMP-13 activity in the culture medium was assayed by gelatin zymography. Results EGCG significantly decreased AGE-stimulated gene expression and production of TNFα and MMP-13 in human chondrocytes. The inhibitory effect of EGCG on the AGE-BSA-induced expression of TNFα and MMP-13 was mediated at least in part via suppression of p38-MAPK and JNK activation. In addition, EGCG inhibited the phosphorylating activity of IKKβ kinase in an in vitro activity assay and EGCG inhibited the AGE-mediated activation and DNA binding activity of NF-κB by suppressing the degradation of its inhibitory protein IκBα in the cytoplasm. Conclusions These novel pharmacological actions of EGCG on AGE-BSA-stimulated human OA chondrocytes provide new suggestions that EGCG or EGCG-derived compounds may inhibit cartilage degradation by suppressing AGE

  1. Xanthatin, a novel potent inhibitor of VEGFR2 signaling, inhibits angiogenesis and tumor growth in breast cancer cells

    PubMed Central

    Yu, Yao; Yu, Jing; Pei, Chong Gang; Li, Yun Yan; Tu, Ping; Gao, Gui Ping; Shao, Yi

    2015-01-01

    Anti-angiogenesis targeting vascular endothelial growth factor receptor 2 (VEGFR2) has emerged as an important tool for cancer treatment. In this study, we described a novel VEGFR2 inhibitor, xanthatin, which inhibits tumor angiogenesis and growth. The biochemical profiles of xanthatin were investigated using kinase assay, migration assay, tube formation, Matrigel plug assay, western blot, immunofluorescence and human tumor xenograft model. Xanthatin significantly inhibited growth, migration and tube formation of human umbilical vascular endothelial cell as well as inhibited vascular endothelial growth factor (VEGF)-stimulated angiogenesis. In addition, it inhibited VEGF-induced phosphorylation of VEGFR2 and its downstream signaling regulator. Moreover, xanthatin directly inhibit proliferation of breast cancer cells MDA-MB-231. Oral administration of xanthatin could markedly inhibit human tumor xenograft growth and decreased microvessel densities (MVD) in tumor sections. Taken together, these preclinical evaluations suggest that xanthatin inhibits angiogenesis and may be a promising anticancer drug candidate. PMID:26617743

  2. Clinically Relevant Doses of Candesartan Inhibit Growth of Prostate Tumor Xenografts In Vivo through Modulation of Tumor Angiogenesis

    PubMed Central

    Alhusban, Ahmed; Al-Azayzih, Ahmad; Goc, Anna; Gao, Fei; Fagan, Susan C.

    2014-01-01

    Angiotensin II receptor type 1 blockers (ARBs), widely used antihypertensive drugs, have also been investigated for their anticancer effects. The effect of ARBs on prostate cancer in experimental models compared with meta-analysis data from clinical trials is conflicting. Whereas this discrepancy might be due to the use of supratherapeutic doses of ARBs in cellular and animal models as compared with the clinical doses used in human trials, further investigation of the effects of clinical doses of ARBs on prostate cancer in experimental models is warranted. In the current study, we sought to determine the effects of candesartan on prostate cancer cellular function in vitro and tumor growth in vivo, and characterize the underlying mechanisms. Our analysis indicated that clinically relevant doses of candesartan significantly inhibited growth of PC3 cell tumor xenografts in mice. Interestingly, the same concentrations of candesartan actually promoted prostate cancer cellular function in vitro, through a modest but significant inhibition in apoptosis. Inhibition of tumor growth by candesartan was associated with a decrease in vascular endothelial growth factor (VEGF) expression in tumors and inhibition of tumor angiogenesis, but normalization of tumor vasculature. Although candesartan did not impair PC3 cell viability, it inhibited endothelial-barrier disruption by tumor-derived factors. Furthermore, candesartan significantly inhibited expression of VEGF in PC3 and DU145 cell lines independent of angiotensin II type 2 receptor, but potentially via angiotensin II type 1 receptor inhibition. Our findings clearly demonstrate the therapeutic potential of candesartan for prostate cancer and establish a link between ARBs, VEGF expression, and prostate tumor angiogenesis. PMID:24990940

  3. Pharmacological inhibition of p38 MAPK reduces tumor growth in patient-derived xenografts from colon tumors

    PubMed Central

    Papaioannou, Marilena; Lopez-Casas, Pedro Pablo; Llonch, Elisabet; Hidalgo, Manuel; Gorgoulis, Vassilis G.; Nebreda, Angel R.

    2015-01-01

    Colorectal cancer is a major health problem and the second cause of cancer related death in western countries. Signaling pathways that control tissue homeostasis are often deregulated during tumorigenesis and contribute to tumor development. Studies in mouse models have shown that the p38 MAPK pathway regulates homeostasis in colon epithelial cells but also plays an important role in colon tumor maintenance. In this study, we have investigated the role of p38 MAPK signaling in patient-derived xenografts (PDXs) from three different human colon tumors representing clinical heterogeneity and that recapitulate the human tumor conditions both at histological and molecular levels. We have found that PH797804, a chemical inhibitor of p38 MAPK, reduces tumor growth of the three PDXs, which correlates with impaired colon tumor cell proliferation and survival. The inhibition of p38 MAPK in PDXs results in downregulation of the IL-6/STAT3 signaling pathway, which is a key regulator of colon tumorigenesis. Our results show the importance of p38 MAPK in human colon tumor growth using a preclinical model, and support that inhibition of p38 MAPK signaling may have therapeutic interest for colon cancer treatment. PMID:25890501

  4. Human Cytomegalovirus Inhibits Erythropoietin Production

    PubMed Central

    Dzabic, Mensur; Bakker, Frank; Davoudi, Belghis; Jeffery, Hannah; Religa, Piotr; Bojakowski, Krzysztof; Yaiw, Koon-Chu; Rahbar, Afsar; Söderberg-Naucler, Cecilia

    2014-01-01

    Anemia is a feature of CKD and a complication of renal transplantation, often caused by impaired production of erythropoietin. The kidney is a target organ for human cytomegalovirus (hCMV) in such patients, but it is not known whether hCMV effects erythropoietin production. We found that kidneys from patients with CKD were positive for hCMV protein and that blood levels of hCMV IgG inversely correlated with red blood cell count. In mice, systemic murine cytomegalovirus infection decreased serum erythropoietin levels. In human erythropoietin-producing cells, hCMV inhibited hypoxia-induced expression of erythropoietin mRNA and protein. hCMV early gene expression was responsible, as ultraviolet-inactivated virus had no effect and valganciclovir treatment showed that late gene expression was nonessential. Hypoxia-induced gene transcription is controlled by the transcription factors hypoxia-inducible transcription factor (HIF)-1α and HIF2α, which are constitutively produced but stable only under low oxygen conditions. We found that hCMV inhibited constitutive production of HIF2α mRNA. HIF2α is thought to be the master regulator of erythropoietin transcription. Single-cell analysis revealed that nuclear accumulation of HIF2α was inhibited in hCMV-infected cells, and the extent of inhibition correlated with hCMV protein expression. Our findings suggest that renal hCMV infection could induce or exacerbate anemia in patients. PMID:24722450

  5. PTEN: Multiple Functions in Human Malignant Tumors

    PubMed Central

    Milella, Michele; Falcone, Italia; Conciatori, Fabiana; Cesta Incani, Ursula; Del Curatolo, Anais; Inzerilli, Nicola; Nuzzo, Carmen M. A.; Vaccaro, Vanja; Vari, Sabrina; Cognetti, Francesco; Ciuffreda, Ludovica

    2015-01-01

    PTEN is the most important negative regulator of the PI3K signaling pathway. In addition to its canonical, PI3K inhibition-dependent functions, PTEN can also function as a tumor suppressor in a PI3K-independent manner. Indeed, the PTEN network regulates a broad spectrum of biological functions, modulating the flow of information from membrane-bound growth factor receptors to nuclear transcription factors, occurring in concert with other tumor suppressors and oncogenic signaling pathways. PTEN acts through its lipid and protein phosphatase activity and other non-enzymatic mechanisms. Studies conducted over the past 10 years have expanded our understanding of the biological role of PTEN, showing that in addition to its ability to regulate proliferation and cell survival, it also plays an intriguing role in regulating genomic stability, cell migration, stem cell self-renewal, and tumor microenvironment. Changes in PTEN protein levels, location, and enzymatic activity through various molecular mechanisms can generate a continuum of functional PTEN levels in inherited syndromes, sporadic cancers, and other diseases. PTEN activity can indeed, be modulated by mutations, epigenetic silencing, transcriptional repression, aberrant protein localization, and post-translational modifications. This review will discuss our current understanding of the biological role of PTEN, how PTEN expression and activity are regulated, and the consequences of PTEN dysregulation in human malignant tumors. PMID:25763354

  6. INHIBITION OF INTERCELLULAR COMMUNICATION BETWEEN MOUSE HEPATOCYTES BY TUMOR PROMOTERS

    EPA Science Inventory

    Tumor promoters can inhibit gap junction-mediated intercellular communication in cultured cells. The authors evaluated the effects of tumor promoters on intercellular communication between B6C3F1 mouse hepatocytes in primary culture. Intercellular communication between donor and ...

  7. Fraxetin inhibits the induction of anti-Fas IgM, tumor necrosis factor-alpha and interleukin-1beta-mediated apoptosis by Fas pathway inhibition in human osteoblastic cell line MG-63.

    PubMed

    Kuo, Po-Lin; Huang, Yu-Ting; Chang, Cheng-Hsiung; Chang, Jiunn-Kae

    2006-07-01

    The survival of osteoblast cells is one of the determinants of the development of osteoporosis in patients with inflamed synovium, such as in rheumatoid arthritis (RA). By means of alkaline phosphatase (ALP) activity and osteocalcin ELISA assay, we have shown that fraxetin exhibits a significant induction of differentiation in the human osteoblast-like cell line MG-63. In addition, we also assessed whether fraxetin affects inflammatory cytokine-mediated apoptosis in osteoblast cells. TNF-alpha or IL-1beta enhance apoptotic DNA fragmentation in anti-Fas IgM-treated MG-63 cells by increasing Fas receptor expression. However, TNF-alpha or IL-1beta treatment alone does not induce apoptosis. Treatment of MG-63 cells with fraxetin not only inhibited anti-Fas IgM-induced apoptosis, but also blocked the synergetic effect of anti-Fas IgM with TNF-alpha or IL-1beta on cell death. The apoptotic inhibition of fraxetin is associated with inhibition of TNF-alpha and IL-1beta-mediated Fas expression and enhancement of FLIP expression, resulting in a decrease of caspase-8 and caspase-3 activation. These results indicate a potential use of fraxetin in preventing osteoporosis by inhibiting inflammatory cytokine-mediated apoptosis in osteoblast cells. PMID:16714221

  8. Suicide HSVtk gene delivery by neurotensin-polyplex nanoparticles via the bloodstream and GCV Treatment specifically inhibit the growth of human MDA-MB-231 triple negative breast cancer tumors xenografted in athymic mice.

    PubMed

    Castillo-Rodríguez, Rosa A; Arango-Rodríguez, Martha L; Escobedo, Lourdes; Hernandez-Baltazar, Daniel; Gompel, Anne; Forgez, Patricia; Martínez-Fong, Daniel

    2014-01-01

    The human breast adenocarcinoma cell line MDA-MB-231 has the triple-negative breast cancer (TNBC) phenotype, which is an aggressive subtype with no specific treatment. MDA-MB-231 cells express neurotensin receptor type 1 (NTSR1), which makes these cells an attractive target of therapeutic genes that are delivered by the neurotensin (NTS)-polyplex nanocarrier via the bloodstream. We addressed the relevance of this strategy for TNBC treatment using NTS-polyplex nanoparticles harboring the herpes simplex virus thymidine kinase (HSVtk) suicide gene and its complementary prodrug ganciclovir (GCV). The reporter gene encoding green fluorescent protein (GFP) was used as a control. NTS-polyplex successfully transfected both genes in cultured MDA-MB-231 cells. The transfection was demonstrated pharmacologically to be dependent on activation of NTSR1. The expression of HSVtk gene decreased cell viability by 49% (P<0.0001) and induced apoptosis in cultured MDA-MB-231 cells after complementary GCV treatment. In the MDA-MB-231 xenograft model, NTS-polyplex nanoparticles carrying either the HSVtk gene or GFP gene were injected into the tumors or via the bloodstream. Both routes of administration allowed the NTS-polyplex nanoparticles to reach and transfect tumorous cells. HSVtk expression and GCV led to apoptosis, as shown by the presence of cleaved caspase-3 and Apostain immunoreactivity, and significantly inhibited the tumor growth (55-60%) (P<0.001). At the end of the experiment, the weight of tumors transfected with the HSVtk gene was 55% less than that of control tumors (P<0.05). The intravenous transfection did not induce apoptosis in peripheral organs. Our results offer a promising gene therapy for TNBC using the NTS-polyplex nanocarrier. PMID:24824754

  9. Suicide HSVtk Gene Delivery by Neurotensin-Polyplex Nanoparticles via the Bloodstream and GCV Treatment Specifically Inhibit the Growth of Human MDA-MB-231 Triple Negative Breast Cancer Tumors Xenografted in Athymic Mice

    PubMed Central

    Castillo-Rodríguez, Rosa A.; Arango-Rodríguez, Martha L.; Escobedo, Lourdes; Hernandez-Baltazar, Daniel; Gompel, Anne

    2014-01-01

    The human breast adenocarcinoma cell line MDA-MB-231 has the triple-negative breast cancer (TNBC) phenotype, which is an aggressive subtype with no specific treatment. MDA-MB-231 cells express neurotensin receptor type 1 (NTSR1), which makes these cells an attractive target of therapeutic genes that are delivered by the neurotensin (NTS)-polyplex nanocarrier via the bloodstream. We addressed the relevance of this strategy for TNBC treatment using NTS-polyplex nanoparticles harboring the herpes simplex virus thymidine kinase (HSVtk) suicide gene and its complementary prodrug ganciclovir (GCV). The reporter gene encoding green fluorescent protein (GFP) was used as a control. NTS-polyplex successfully transfected both genes in cultured MDA-MB-231 cells. The transfection was demonstrated pharmacologically to be dependent on activation of NTSR1. The expression of HSVtk gene decreased cell viability by 49% (P<0.0001) and induced apoptosis in cultured MDA-MB-231 cells after complementary GCV treatment. In the MDA-MB-231 xenograft model, NTS-polyplex nanoparticles carrying either the HSVtk gene or GFP gene were injected into the tumors or via the bloodstream. Both routes of administration allowed the NTS-polyplex nanoparticles to reach and transfect tumorous cells. HSVtk expression and GCV led to apoptosis, as shown by the presence of cleaved caspase-3 and Apostain immunoreactivity, and significantly inhibited the tumor growth (55–60%) (P<0.001). At the end of the experiment, the weight of tumors transfected with the HSVtk gene was 55% less than that of control tumors (P<0.05). The intravenous transfection did not induce apoptosis in peripheral organs. Our results offer a promising gene therapy for TNBC using the NTS-polyplex nanocarrier. PMID:24824754

  10. X-ray sensitivity of human tumor cells in vitro

    SciTech Connect

    Weichselbaum, R.R.; Nove, J.; Little, J.B.

    1980-04-01

    Clonally-derived cells from ten human malignant tumors considered radiocurable (breast, neuroblastoma, medulloblastoma) or non-radiocurable (osteosarcoma, hypernephroma, glioblastoma, melanoma) were studied in cell culture and their in vitro x-ray survival curve parameters determined (anti n, D/sub 0/). There were no significant differences among the tumor cell lines suggesting that survival parameters in vitro do not explain differences in clinical radiocurability. Preliminary investigation with density inhibited human tumor cells indicate that such an approach may yield information regarding inherent cellular differences in radiocurability.

  11. Segetoside I, a plant-derived bisdesmosidic saponin, induces apoptosis in human hepatoma cells in vitro and inhibits tumor growth in vivo.

    PubMed

    Firempong, Caleb Kesse; Zhang, Hui Yun; Wang, Yan; Chen, Jingjing; Cao, Xia; Deng, Wenwen; Zhou, Jie; Wang, Qiang; Tong, Shan-Shan; Yu, Jiangnan; Xu, Ximing

    2016-08-01

    Segetoside I is a plant-derived bisdesmosidic saponin from Vaccaria segetalis (Neck) with reported anticancer activities. This development has raised an interest in the therapeutic potential of segetoside I. Here, we report the in vitro and in vivo antitumor activities of segetoside I against some selected cancer cell lines (HepG2, human hepatoma; H22, mouse hepatoma; MCF-7, breast cancer; U251, gliocoma; BGC, HGC & SGC, gastric cancinoma; Lovo-1,colon cancer). MTT bioassay analysis showed that HepG2 cells were the most sensitive to segetoside I compared with other cancer cell lines, with lower toxicity in healthy mouse embryonic fibroblast cells. Segetoside I pretreatment of HepG2 resulted in apoptotic induction, dose-dependent DNA fragmentation, inhibition of cell migration, up-regulation of Bax and down-regulation of Bcl-2, which indicated that an apoptotic signaling event could have been initiated. The segetoside I also suppressed hepato-tumour growth in mice with virtually no cytotoxicity and prolonged animal survival, making it a strong oncology drug agent. These findings showed that segetoside I exhibited its antitumor activity via apoptotic induction and significantly support the possible application of the antitumor agent as a potential chemotherapeutic candidate worthy of further investigations. PMID:27180010

  12. Nanoelectroablation of Murine Tumors Triggers a CD8-Dependent Inhibition of Secondary Tumor Growth

    PubMed Central

    Nuccitelli, Richard; Berridge, Jon Casey; Mallon, Zachary; Kreis, Mark; Athos, Brian; Nuccitelli, Pamela

    2015-01-01

    We have used both a rat orthotopic hepatocellular carcinoma model and a mouse allograft tumor model to study liver tumor ablation with nanosecond pulsed electric fields (nsPEF). We confirm that nsPEF treatment triggers apoptosis in rat liver tumor cells as indicated by the appearance of cleaved caspase 3 and 9 within two hours after treatment. Furthermore we provide evidence that nsPEF treatment leads to the translocation of calreticulin (CRT) to the cell surface which is considered a damage-associated molecular pattern indicative of immunogenic cell death. We provide direct evidence that nanoelectroablation triggers a CD8-dependent inhibition of secondary tumor growth by comparing the growth rate of secondary orthotopic liver tumors in nsPEF-treated rats with that in nsPEF-treated rats depleted of CD8+ cytotoxic T-cells. The growth of these secondary tumors was severely inhibited as compared to tumor growth in CD8-depleated rats, with their average size only 3% of the primary tumor size after the same one-week growth period. In contrast, when we depleted CD8+ T-cells the second tumor grew more robustly, reaching 54% of the size of the first tumor. In addition, we demonstrate with immunohistochemistry that CD8+ T-cells are highly enriched in the secondary tumors exhibiting slow growth. We also showed that vaccinating mice with nsPEF-treated isogenic tumor cells stimulates an immune response that inhibits the growth of secondary tumors in a CD8+-dependent manner. We conclude that nanoelectroablation triggers the production of CD8+ cytotoxic T-cells resulting in the inhibition of secondary tumor growth. PMID:26231031

  13. Lithium inhibits tumor lymphangiogenesis and metastasis through the inhibition of TGFBIp expression in cancer cells

    PubMed Central

    Maeng, Yong-Sun; Lee, Rina; Lee, Boram; Choi, Seung-il; Kim, Eung Kweon

    2016-01-01

    Metastasis is the main cause of mortality in cancer patients. Although there are many anti-cancer drugs targeting tumor growth, anti-metastatic agents are rarely developed. Angiogenesis and lymphangiogenesis are crucial for cancer progression; in particular, lymphangiogenesis is pivotal for metastasis in cancer. Here we report that lithium inhibits colon cancer metastasis by blocking lymphangiogenesis. Lithium reduces the expression of transforming growth factor-β-induced protein (TGFBIp) in colon cancer cells by inhibiting Smad3 phosphorylation via GSK3β inactivation. Moreover, lithium inhibits lymphatic endothelial cell migration, which is increased upon TGFBIp expression in tumor cells. Lithium had no significant effect on SW620 tumor growth in vitro and in vivo; however, it inhibited lymphangiogenesis in tumors. In tumor xenografts model, lithium was found to prevent metastasis to the lungs, liver, and lymph nodes by inhibiting TGFBIp-induced tumor lymphangiogenesis. Collectively, our findings demonstrate a novel role of lithium in the inhibition of colon cancer metastasis by blocking TGFBIp expression, and thereby TGFBIp-induced lymphangiogenesis, in primary tumors. PMID:26857144

  14. Lithium inhibits tumor lymphangiogenesis and metastasis through the inhibition of TGFBIp expression in cancer cells.

    PubMed

    Maeng, Yong-Sun; Lee, Rina; Lee, Boram; Choi, Seung-Il; Kim, Eung Kweon

    2016-01-01

    Metastasis is the main cause of mortality in cancer patients. Although there are many anti-cancer drugs targeting tumor growth, anti-metastatic agents are rarely developed. Angiogenesis and lymphangiogenesis are crucial for cancer progression; in particular, lymphangiogenesis is pivotal for metastasis in cancer. Here we report that lithium inhibits colon cancer metastasis by blocking lymphangiogenesis. Lithium reduces the expression of transforming growth factor-β-induced protein (TGFBIp) in colon cancer cells by inhibiting Smad3 phosphorylation via GSK3β inactivation. Moreover, lithium inhibits lymphatic endothelial cell migration, which is increased upon TGFBIp expression in tumor cells. Lithium had no significant effect on SW620 tumor growth in vitro and in vivo; however, it inhibited lymphangiogenesis in tumors. In tumor xenografts model, lithium was found to prevent metastasis to the lungs, liver, and lymph nodes by inhibiting TGFBIp-induced tumor lymphangiogenesis. Collectively, our findings demonstrate a novel role of lithium in the inhibition of colon cancer metastasis by blocking TGFBIp expression, and thereby TGFBIp-induced lymphangiogenesis, in primary tumors. PMID:26857144

  15. Genistein suppresses FLT4 and inhibits human colorectal cancer metastasis.

    PubMed

    Xiao, Xiao; Liu, Zhiguo; Wang, Rui; Wang, Jiayin; Zhang, Song; Cai, Xiqiang; Wu, Kaichun; Bergan, Raymond C; Xu, Li; Fan, Daiming

    2015-02-20

    Dietary consumption of genistein, found in soy, has been associated with a potentially protective role in colorectal cancer (CRC) development and progression. Herein we demonstrate that genistein will inhibit human CRC cell invasion and migration, that it does so at non-cytotoxic concentrations and we demonstrate this in multiple human CRC cell lines. After orthotopic implantation of human CRC tumors into mice, oral genistein did not inhibit tumor growth, but did inhibit distant metastasis formation, and was non-toxic to mice. Using a qPCR array, we screened for genistein-induced changes in gene expression, followed by Western blot confirmation, demonstrating that genistein downregulated matrix metalloproteinase 2 and Fms-Related Tyrosine Kinase 4 (FLT4; vascular endothelial growth factor receptor 3). After demonstrating that genistein suppressed neo-angiogenesis in mouse tumors, we examined FLT4 expression in primary CRC and adjacent normal colonic tissue from 60 human subjects, demonstrating that increased FLT4 significantly correlates with increased stage and decreased survival. In summary, we demonstrate for the first time that genistein inhibits human CRC metastasis at dietary, non-toxic, doses. FLT4 is identified as a marker of metastatic disease, and as a response marker for small molecule therapeutics that inhibit CRC metastasis. PMID:25605009

  16. Polyphenols in brewed green tea inhibit prostate tumor xenograft growth by localizing to the tumor and decreasing oxidative stress and angiogenesis.

    PubMed

    Henning, Susanne M; Wang, Piwen; Said, Jonathan; Magyar, Clara; Castor, Brandon; Doan, Ngan; Tosity, Carmen; Moro, Aune; Gao, Kun; Li, Luyi; Heber, David

    2012-11-01

    It has been demonstrated in various animal models that the oral administration of green tea (GT) extracts in drinking water can inhibit tumor growth, but the effects of brewed GT on factors promoting tumor growth, including oxidant damage of DNA and protein, angiogenesis and DNA methylation, have not been tested in an animal model. To explore these potential mechanisms, brewed GT was administered instead of drinking water to male severe combined immunodeficiency (SCID) mice with androgen-dependent human LAPC4 prostate cancer cell subcutaneous xenografts. Tumor volume was decreased significantly in mice consuming GT, and tumor size was significantly correlated with GT polyphenol (GTP) content in tumor tissue. There was a significant reduction in hypoxia-inducible factor 1-alpha and vascular endothelial growth factor protein expression. GT consumption significantly reduced oxidative DNA and protein damage in tumor tissue as determined by 8-hydroxydeoxyguanosine/deoxyguanosine ratio and protein carbonyl assay, respectively. Methylation is known to inhibit antioxidative enzymes such as glutathione S-transferase pi to permit reactive oxygen species promotion of tumor growth. GT inhibited tumor 5-cytosine DNA methyltransferase 1 mRNA and protein expression significantly, which may contribute to the inhibition of tumor growth by reactivation of antioxidative enzymes. This study advances our understanding of tumor growth inhibition by brewed GT in an animal model by demonstrating tissue localization of GTPs in correlation with inhibition of tumor growth. Our results suggest that the inhibition of tumor growth is due to GTP-mediated inhibition of oxidative stress and angiogenesis in the LAPC4 xenograft prostate tumor in SCID mice. PMID:22405694

  17. The retinoblastoma gene in human pituitary tumors

    SciTech Connect

    Cryns, V.L.; Arnold, A.; Alexander, J.M.; Klibanski, A. )

    1993-09-01

    Functional inactivation of the retinoblastoma (RB) tumor suppressor gene is important in the pathogenesis of many human tumors. Recently, the frequent occurrence of pituitary tumors was reported in mice genetically engineered to have one defective RB allele, a genetic background analogous to that of patients with familial retinoblastoma. The molecular pathogenesis of human pituitary tumors is largely unknown, and the potential role of RB gene inactivation in these neoplasms has not been examined. Consequently, the authors studied 20 human pituitary tumors (12 clinically nonfunctioning tumors, 4 somatotroph adenomas, 2 prolactinomas, and 2 corticotrophy adenomas) for tumor-specific allelic loss of the RB gene using a highly informative polymorphic locus within the gene. Control leukocyte DNA samples from 18 of these 20 patients were heterozygous at this locus, permitting genetic evaluation of their paired tumor specimens. In contrast to the pituitary tumors in the mouse model, none of these 18 human tumors exhibited RB allelic loss. These findings indicate that RB gene inactivation probably does not play an important role in the pathogenesis of common types of human pituitary tumors. 24 refs., 1 fig.

  18. CBL enhances breast tumor formation by inhibiting tumor suppressive activity of TGF-β signaling.

    PubMed

    Kang, J M; Park, S; Kim, S J; Hong, H Y; Jeong, J; Kim, H-S; Kim, S-J

    2012-12-13

    Casitas B-lineage lymphoma (CBL) protein family functions as multifunctional adaptor proteins and E3 ubiquitin ligases that are implicated as regulators of signaling in various cell types. Recent discovery revealed mutations of proto-oncogenic CBL in the linker region and RING finger domain in human acute myeloid neoplasm, and these transforming mutations induced carcinogenesis. However, the adaptor function of CBL mediated signaling pathway during tumorigenesis has not been well characterized. Here, we show that CBL is highly expressed in breast cancer cells and significantly inhibits transforming growth factor-β (TGF-β) tumor suppressive activity. Knockdown of CBL expression resulted in the increased expression of TGF-β target genes, PAI-I and CDK inhibitors such as p15(INK4b) and p21(Cip1). Furthermore, we demonstrate that CBL is frequently overexpressed in human breast cancer tissues, and the loss of CBL decreases the tumorigenic activity of breast cancer cells in vivo. CBL directly binds to Smad3 through its proline-rich motif, thereby preventing Smad3 from interacting with Smad4 and blocking nuclear translocation of Smad3. CBL-b, one of CBL protein family, also interacted with Smad3 and knockdown of both CBL and CBL-b further enhanced TGF-β transcriptional activity. Our findings provide evidence for a previously undescribed mechanism by which oncogenic CBL can block TGF-β tumor suppressor activity. PMID:22310290

  19. Ex-vivo in-vitro inhibition of lipopolysaccharide stimulated tumor necrosis factor-alpha and interleukin-1 beta secretion in human whole blood by extractum urticae dioicae foliorum.

    PubMed

    Obertreis, B; Ruttkowski, T; Teucher, T; Behnke, B; Schmitz, H

    1996-04-01

    An extract of Urtica dioica folium (IDS 23, Rheuma-Hek), monographed positively for adjuvant therapy of rheumatic diseases and with known effects in partial inhibition of prostaglandin and leukotriene synthesis in vitro, was investigated with respect to effects of the extract on the lipopolysaccharide (LPS) stimulated secretion of proinflammatory cytokines in human whole blood of healthy volunteers. In the assay system used, LPS stimulated human whole blood showed a straight increase of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) secretion reaching maximum concentrations within 24 h following a plateau and slight decrease up to 65 h, respectively. The concentrations of these cytokines was strongly positively correlated with the number of monocytes/macrophages of each volunteer. TNF-alpha and IL-1 beta concentration after LPS stimulation was significantly reduced by simultaneously given IDS 23 in a strictly dose dependent manner. At time 24 h these cytokine concentrations were reduced by 50.8% and 99.7%, respectively, using the highest test IDS 23 assay concentration of 5 mg/ml (p < 0.001). After 65 h the corresponding inhibition was 38.9% and 99.9%, respectively (p < 0.001). On the other hand IDS 23 showed no inhibition but stimulated IL-6 secretion in absence of LPS alone. Simultaneously given LPS and IDS 23 resulted in no further increase. In contrast to described effects on arachidonic acid cascade in vitro, tested Urtica dioica phenol carbon acid derivates and flavonoides such as caffeic malic acid, caffeic acid, chlorogenic acid, quercetin and rutin did not influence LPS stimulated TNF-alpha, IL-1 beta and IL-6 secretion in tested concentrations up to 5 x 10(-5) mol/l. These further findings on the pharmacological mechanism of action of Urticae dioica folia may explain the positive effects of this extract in the treatment of rheumatic diseases. PMID:8740085

  20. cdk4 Deficiency Inhibits Skin Tumor Development but Does Not Affect Normal Keratinocyte Proliferation

    PubMed Central

    Rodriguez-Puebla, Marcelo L.; Miliani de Marval, Paula L.; LaCava, Margaret; Moons, David S.; Kiyokawa, Hiroaki; Conti, Claudio J.

    2002-01-01

    Most human tumors have mutations that result in deregulation of the cdk4/cyclin-Ink4-Rb pathway. Overexpression of D-type cyclins or cdk4 and inactivation of Ink4 inhibitors are common in human tumors. Conversely, lack of cyclin D1 expression results in significant reduction in mouse skin and mammary tumor development. However, complete elimination of tumor development was not observed in these models, suggesting that other cyclin/cdk complexes play an important role in tumorigenesis. Here we described the effects of cdk4 deficiency on mouse skin proliferation and tumor development. Cdk4 deficiency resulted in a 98% reduction in the number of tumors generated through the two-stage carcinogenesis model. The absence of cdk4 did not affect normal keratinocyte proliferation and both wild-type and cdk4 knockout epidermis are equally affected after topical treatment with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA), resulting in epidermal hyperplasia. In similar fashion, cdk4 knockout keratinocytes proliferated well in an in vivo model of wound-induced proliferation. Biochemical studies in mouse epidermis showed that cdk6 activity increased twofold in cdk4-deficient mice compared to wild-type siblings. These results suggest that therapeutic approaches to inhibit cdk4 activity could provide a target to inhibit tumor development with minimal or no effect in normal tissue. PMID:12163365

  1. Salmonella overcomes tumor immune tolerance by inhibition of tumor indoleamine 2, 3-dioxygenase 1 expression.

    PubMed

    Kuan, Yu-Diao; Lee, Che-Hsin

    2016-01-01

    Over the past decades, Salmonella has been proven capable of inhibiting tumor growth. It can specifically target tumors and due to its facultative anaerobic property, can be more penetrative than other drug therapies. However, the molecular mechanism by which Salmonella inhibits tumor growth is still incompletely known. The antitumor therapeutic effect mediated by Salmonella is associated with an inflammatory immune response at the tumor site and a T cell-dependent immune response. Many tumors have been proven to have a high expression of indoleamine 2, 3-dioxygenase 1 (IDO), which is a rate-limiting enzyme that catalyzes tryptophan to kynurenine, thus causing immune tolerance within the tumor microenvironment. With decreased expression of IDO, increased immune response can be observed, which might be helpful when developing cancer immunotherapy. The expression of IDO was decreased after tumor cells were infected with Salmonella. In addition, Western blot analysis showed that the expression levels of phospho-protein kinase B (P-AKT), phospho-mammalian targets of rapamycin (P-mTOR), and phospho-p70 ribosomal s6 kinase (P-p70s6K) in tumor cells were decreased after Salmonella infection. In conclusion, our results indicate that Salmonella inhibits IDO expression and plays a crucial role in anti-tumor therapy, which might be a promising strategy combined with other cancer treatments. PMID:26517244

  2. Squalamine inhibits angiogenesis and solid tumor growth in vivo and perturbs embryonic vasculature.

    PubMed

    Sills, A K; Williams, J I; Tyler, B M; Epstein, D S; Sipos, E P; Davis, J D; McLane, M P; Pitchford, S; Cheshire, K; Gannon, F H; Kinney, W A; Chao, T L; Donowitz, M; Laterra, J; Zasloff, M; Brem, H

    1998-07-01

    The novel aminosterol, squalamine, inhibits angiogenesis and tumor growth in multiple animal models. This effect is mediated, at least in part, by blocking mitogen-induced proliferation and migration of endothelial cells, thus preventing neovascularization of the tumor. Squalamine has no observable effect on unstimulated endothelial cells, is not directly cytotoxic to tumor cells, does not alter mitogen production by tumor cells, and has no obvious effects on the growth of newborn vertebrates. Squalamine was also found to have remarkable effects on the primitive vascular bed of the chick chorioallantoic membrane, which has striking similarities to tumor capillaries. Squalamine may thus be well suited for treatment of tumors and other diseases characterized by neovascularization in humans. PMID:9661892

  3. Vascular tumors have increased p70 S6-kinase activation and are inhibited by topical rapamycin.

    PubMed

    Du, Wa; Gerald, Damien; Perruzzi, Carole A; Rodriguez-Waitkus, Paul; Enayati, Ladan; Krishnan, Bhuvaneswari; Edmonds, Joseph; Hochman, Marcelo L; Lev, Dina C; Phung, Thuy L

    2013-10-01

    Vascular tumors are endothelial cell neoplasms whose cellular and molecular mechanisms, leading to tumor formation, are poorly understood, and current therapies have limited efficacy with significant side effects. We have investigated mechanistic (mammalian) target of rapamycin (mTOR) signaling in benign and malignant vascular tumors, and the effects of mTOR kinase inhibitor as a potential therapy for these lesions. Human vascular tumors (infantile hemangioma and angiosarcoma) were analyzed by immunohistochemical stains and western blot for the phosphorylation of p70 S6-kinase (S6K) and S6 ribosomal protein (S6), which are activated downstream of mTOR complex-1 (mTORC1). To assess the function of S6K, tumor cells with genetic knockdown of S6K were analyzed for cell proliferation and migration. The effects of topical rapamycin, an mTOR inhibitor, on mTORC1 and mTOR complex-2 (mTORC2) activities, as well as on tumor growth and migration, were determined. Vascular tumors showed increased activation of S6K and S6. Genetic knockdown of S6K resulted in reduced tumor cell proliferation and migration. Rapamycin fully inhibited mTORC1 and partially inhibited mTORC2 activities, including the phosphorylation of Akt (serine 473) and PKCα, in vascular tumor cells. Rapamycin significantly reduced vascular tumor growth in vitro and in vivo. As a potential localized therapy for cutaneous vascular tumors, topically applied rapamycin effectively reduced tumor growth with limited systemic drug absorption. These findings reveal the importance of mTOR signaling pathways in benign and malignant vascular tumors. The mTOR pathway is an important therapeutic target in vascular tumors, and topical mTOR inhibitors may provide an alternative and well-tolerated therapy for the treatment of cutaneous vascular lesions. PMID:23938603

  4. Morelloflavone, a biflavonoid, inhibits tumor angiogenesis by targeting Rho GTPases and ERK signaling pathways

    PubMed Central

    Pang, Xiufeng; Yi, Tingfang; Yi, Zhengfang; Cho, Sung Gook; Qu, Weijing; Pinkaew, Decha; Fujise, Ken; Liu, Mingyao

    2009-01-01

    Morelloflavone, a biflavonoid extracted from Garcinia dulcis, has shown anti-oxidative, antiviral, and anti-inflammatory properties. However, the function and the mechanism of this compound in cancer treatment and tumor angiogenesis have not been elucidated to date. In this study, we postulated that morelloflavone might have the ability to inhibit angiogenesis, the pivotal step in tumor growth, invasiveness and metastasis. We demonstrated that morelloflavone could inhibit vascular endothelial growth factor (VEGF)-induced cell proliferation, migration, invasion, and capillary-like tube formation of primary cultured human umbilical endothelial cells (HUVECs) in a dose-dependent manner. Morelloflavone effectively inhibited microvessel sprouting of endothelial cells in the rat aortic ring assay and the formation of new blood microvessels induced by VEGF in the mouse Matrigel plug assay. Furthermore, morelloflavone inhibited tumor growth and tumor angiogenesis of prostate cancer cells (PC-3) in xenograft mouse tumor model in vivo, suggesting that morelloflavone inhibited tumorigenesis by targeting angiogenesis. To understand the underlying mechanism of morelloflavone on the inhibitory effect of tumor growth and angiogenesis, we demonstrated that morelloflavone could inhibit the activation of both RhoA and Rac1 GTPases, but have little effect on the activation of Cdc42 GTPase. Additionally, morelloflavone inhibited the phosphorylation and activation of Raf/MEK/ERK pathway kinases without affecting VEGFR2 activity. Together, our results indicate that morelloflavone exerts anti-angiogenic action by targeting the activation of Rho-GTPases and ERK signaling pathways. These findings are the first to reveal the novel functions of morelloflavone in tumor angiogenesis and its molecular basis for the anticancer action. PMID:19147565

  5. Heme oxygenase-1 accelerates tumor angiogenesis of human pancreatic cancer.

    PubMed

    Sunamura, Makoto; Duda, Dan G; Ghattas, Maivel H; Lozonschi, Lucian; Motoi, Fuyuhiko; Yamauchi, Jun-Ichiro; Matsuno, Seiki; Shibahara, Shigeki; Abraham, Nader G

    2003-01-01

    Angiogenesis is necessary for the continued growth of solid tumors, invasion and metastasis. Several studies clearly showed that heme oxygenase-1 (HO-1) plays an important role in angiogenesis. In this study, we used the vital microscope system, transparent skinfold model, lung colonization model and transduced pancreatic cancer cell line (Panc-1)/human heme oxygenase-1 (hHO-1) cells, to precisely analyze, for the first time, the effect of hHO-1 gene on tumor growth, angiogenesis and metastasis. Our results revealed that HO-1 stimulates angiogenesis of pancreatic carcinoma in severe combined immune deficient mice. Overexpression of human hHO-1 after its retroviral transfer into Panc-1 cells did not interfere with tumor growth in vitro. While in vivo the development of tumors was accelerated upon transfection with hHO-1. On the other hand, inhibition of heme oxygenase (HO) activity by stannous mesoporphyrin was able transiently to delay tumor growth in a dose dependent manner. Tumor angiogenesis was markedly increased in Panc-1/hHO-1 compared to mock transfected and wild type. Lectin staining and Ki-67 proliferation index confirmed these results. In addition hHO-1 stimulated in vitro tumor angiogenesis and increased endothelial cell survival. In a lung colonization model, overexpression of hHO-1 increased the occurrence of metastasis, while inhibition of HO activity by stannous mesoporphyrin completely inhibited the occurrence of metastasis. In conclusion, overexpression of HO-1 genes potentiates pancreatic cancer aggressiveness, by increasing tumor growth, angiogenesis and metastasis and that the inhibition of the HO system may be of useful benefit for the future treatment of the disease. PMID:14517400

  6. Bicarbonate Increases Tumor pH and Inhibits Spontaneous Metastases

    PubMed Central

    Robey, Ian F.; Baggett, Brenda K.; Kirkpatrick, Nathaniel D.; Roe, Denise J.; Dosescu, Julie; Sloane, Bonnie F.; Hashim, Arig Ibrahim; Morse, David L.; Raghunand, Natarajan; Gatenby, Robert A.; Gillies, Robert J.

    2010-01-01

    The external pH of solid tumors is acidic as a consequence of increased metabolism of glucose and poor perfusion. Acid pH has been shown to stimulate tumor cell invasion and metastasis in vitro and in cells before tail vein injection in vivo. The present study investigates whether inhibition of this tumor acidity will reduce the incidence of in vivo metastases. Here, we show that oral NaHCO3 selectively increased the pH of tumors and reduced the formation of spontaneous metastases in mouse models of metastatic breast cancer. This treatment regimen was shown to significantly increase the extracellular pH, but not the intracellular pH, of tumors by 31P magnetic resonance spectroscopy and the export of acid from growing tumors by fluorescence microscopy of tumors grown in window chambers. NaHCO3 therapy also reduced the rate of lymph node involvement, yet did not affect the levels of circulating tumor cells, suggesting that reduced organ metastases were not due to increased intravasation. In contrast, NaHCO3 therapy significantly reduced the formation of hepatic metastases following intrasplenic injection, suggesting that it did inhibit extravasation and colonization. In tail vein injections of alternative cancer models, bicarbonate had mixed results, inhibiting the formation of metastases from PC3M prostate cancer cells, but not those of B16 melanoma. Although the mechanism of this therapy is not known with certainty, low pH was shown to increase the release of active cathepsin B, an important matrix remodeling protease. PMID:19276390

  7. Temporal mTOR inhibition protects Fbxw7-deficient mice from radiation-induced tumor development

    PubMed Central

    Liu, Yueyong; Huang, Yurong; Wang, Zeran; Huang, Yong; Li, Xiaohua; Louie, Alexander; Wei, Guangwei; Mao, Jian-Hua

    2013-01-01

    FBXW7 acts as a tumor suppressor in numerous types of human cancers through ubiquitination of different oncoproteins including mTOR. However, how the mutation/loss of Fbxw7 results in tumor development remains largely unknown. Here we report that downregulation of mTOR by radiation is Fbxw7-dependent, and short-term mTOR inhibition by rapamycin after exposure to radiation significantly postpones tumor development in Fbxw7/p53 double heterozygous (Fbxw7+/−p53+/−) mice but not in p53 single heterozygous (p53+/−) mice. Tumor latency of rapamycin treated Fbxw7+/−p53+/− mice is remarkably similar to those of p53+/− mice while placebo treated Fbxw7+/−p53+/− mice develop tumor significantly earlier than placebo treated p53+/− mice. Furthermore, we surprisingly find that, although temporal treatment of rapamycin is given at a young age, the inhibition of mTOR activity sustainably remains in tumors. These results indicate that inhibition of mTOR signaling pathway suppresses the contribution of Fbxw7 loss toward tumor development. PMID:23454868

  8. DT-13 inhibits cancer cell migration by regulating NMIIA indirectly in the tumor microenvironment.

    PubMed

    Du, Hongzhi; Huang, Yue; Hou, Xiaoyin; Yu, Xiaowen; Lin, Sensen; Wei, Xiaohui; Li, Ruiming; Khan, Ghulam Jilany; Yuan, Shengtao; Sun, Li

    2016-08-01

    Tumor metastasis is one of the main causes of mortality among patients with malignant tumors. Previous studies concerning tumor metastasis have merely focused on the cancer cells in the tumor. However, an increasing number of studies show that the tumor microenvironment plays a vital role in the progression of cancer, particularly in tumor metastasis. Since fibroblasts and adipocytes are two of the most representative mesenchymal cells in the tumor microenvironment, we established a hypoxia-induced cancer-associated fibroblast (CAF) model and a chemically induced adipocyte model to reveal the effect of the microenvironment on cancer development. In these models, the conditioned medium from the tumor microenvironment was found to significantly promote the migration of human lung cancer cell line 95D and regulate the expression of non-muscle myosin IIA (NMIIA), which is consistent with results in the published literature. Then, we confirmed the hypothesis that the tumor microenvironment can regulate NMIIA in cancer cells and facilitate migration by using the non-muscle myosin II inhibitor, blebbistatin. Thus, this is the first report that the tumor microenvironment can promote cancer cell migration by regulating the expression of NMIIA. Our present data also indicated that DT-13, the saponin monomer 13 of dwarf lilyturf tuber, inhibited cancer cell migration in the tumor microenvironment model. Further results showed that DT-13 exhibited anti-migratory effects by inhibiting the c-raf/ERK1/2 signaling pathway. Consequently, our research confirmed that DT-13 significantly inhibited 95D cell migration in vitro, indicating the potential anti-metastatic effect of DT-13 on lung cancer and the scientific basis for drug development. PMID:27350172

  9. SAMHD1 is down regulated in lung cancer by methylation and inhibits tumor cell proliferation

    SciTech Connect

    Wang, Jia-lei; Lu, Fan-zhen; Shen, Xiao-Yong; Wu, Yun; Zhao, Li-ting

    2014-12-12

    Highlights: • SAMHD1 expression level is down regulated in lung adenocarcinoma. • The promoter of SAMHD1 is methylated in lung adenocarcinoma. • Over expression of SAMHD1 inhibits the proliferation of lung cancer cells. - Abstract: The function of dNTP hydrolase SAMHD1 as a viral restriction factor to inhibit the replication of several viruses in human immune cells was well established. However, its regulation and function in lung cancer have been elusive. Here, we report that SAMHD1 is down regulated both on protein and mRNA levels in lung adenocarcinoma compared to adjacent normal tissue. We also found that SAMHD1 promoter is highly methylated in lung adenocarcinoma, which may inhibit its gene expression. Furthermore, over expression of the SAMHD1 reduces dNTP level and inhibits the proliferation of lung tumor cells. These results reveal the regulation and function of SAMHD1 in lung cancer, which is important for the proliferation of lung tumor cells.

  10. Infrared Spectra of Human Breast Tumor Tissue and Experimental Animal Tumors

    NASA Astrophysics Data System (ADS)

    Tolstorozhev, G. B.; Belkov, M. V.; Skornyakov, I. V.; Pekhnyo, V. I.; Kozachkova, A. N.; Tsarik, H. V.; Kutsenko, I. P.; Sharykina, N. I.; Butra, V. A.

    2015-01-01

    We have used Fourier transform IR spectroscopy methods to conduct comparative studies of human breast tumors and sarcoma 180 tumor grafted into mice. The IR spectral parameters used to identify tumor tissue in mice with the sarcoma 180 strain proved to be identical to the parameters for human breast tissue in cancer. In the presence of a malignant tumor in humans, the most intense C=O vibrational bands in the protein molecules are observed in the interval 1710-1680 cm-1. For a benign tumor, in the IR spectra of breast tissue the intense bands are located in the interval 1670-1650 cm-1. We spectroscopically monitored the diagnosis and the chemotherapy process using the model of sarcoma 180 in mice. As the therapeutic drugs, we used synthesized coordination compounds based on palladium complexes with diphosphonic acid derivatives. We demonstrate the promising potential of palladium complexes with zoledronic acid as an effective cytostatic. In therapy using a palladium complex with zoledronic acid, the effect of tumor growth inhibition is accompanied by a change in its spectral characteristics. The parameters of the IR spectra for tumor tissue after treatment are close to those of the IR spectra for healthy tissue.

  11. CA-1H, a novel oxazole bearing analogue of combretastatin A-4, disrupts the tumor vasculatures and inhibits the tumor growth via inhibiting tubulin polymerization.

    PubMed

    Han, Fuguo; Wang, Peng; Zhang, Wei; Li, Jing; Zhang, Qun; Qi, Xin; Liu, Ming

    2016-05-01

    Vascular disrupting agents destroy established tumor vasculatures selectively, and have achieved encouraging antitumor activity in both pre-clinical and clinical trials. In the present study, we reported the vascular disruption and antitumor effects of CA-1H and its prodrug CA-1HP, oxazole bearing analogues of combretastatin A-4 (CA4). CA-1H was a tighter binder of tubulin than CA4 with the same binding site to chochcine and CA4, and inhibited tubulin polymerization both in cell free system and in human umbilical vein endothelial cells (HUVECs). Furthermore, CA-1H significantly disrupted the microtubulin skeleton in proliferating HUVECs rather than the quiescent ones, damaged the HUVECs-preformed tubes markedly, and lead to necrosis in tumor tissues in NCI-H1975 xenograft mice. Continuous administration for 19 days, CA-1HP could inhibit the NCI-H1975 xenograft tumor growth significantly without obvious weight loss and normal tissue damage, in addition, CA-1HP also inhibited the tumor growth in H22 hepatocellular carcinoma bearing mice; and combination CA-1HP with cisplatin showed more potent antitumor activity than used alone. Taken together, our present investigation suggested that CA-1H was a potential vascular disrupting agent for further development of antitumor drugs. PMID:27133052

  12. Marked inhibition of tumor growth in a malignant glioma tumor model by a novel synthetic matrix metalloproteinase inhibitor AG3340.

    PubMed

    Price, A; Shi, Q; Morris, D; Wilcox, M E; Brasher, P M; Rewcastle, N B; Shalinsky, D; Zou, H; Appelt, K; Johnston, R N; Yong, V W; Edwards, D; Forsyth, P

    1999-04-01

    Synthetic matrix metalloproteinase (MMP) inhibitors have activity against a variety of tumors in preclinical models but have not been studied in gliomas. We determined the effect of AG3340, a novel synthetic MMP inhibitor with Ki values against gelatinases in the low picomolar range, on the growth of a human malignant glioma cell line (U87) in SCID-NOD mice. Mice were injected s.c. with U87 cells. Tumors were allowed to grow to a size of approximately 0.5 x 0.5 cm (after about 3 weeks), and the mice were randomized to receive either: (a) 100 mg/kg AG3340 in vehicle; or (b) vehicle control (0.5% carboxymethyl cellulose, 0.1% pluronic F68), both given daily i.p. Tumor area was measured twice weekly, and animals were sacrificed when moribund, or earlier if premorbid histology was examined. In vivo inhibition of tumor growth was profound, with AG3340 decreasing tumor size by 78% compared with controls after 31 days (when controls were sacrificed; P < 0.01, Wilcoxon test). Control animals survived 31 days after the i.p. injections began, and AG3340 mice survived 71 days, representing a >2-fold increase in survival associated with tumor growth delay. Histological examination found that AG3340-treated tumors were smaller, had lower rates of proliferation, and significantly less invasion than control-treated tumors. Hepatic or pulmonary metastases were not seen in either group. In a separate experiment, the tumors were smaller and sampled after a shorter duration of treatment; the changes in proliferation were more marked and occurred earlier than differences in tumor invasion between the two groups. Furthermore, in vitro cell growth was not inhibited at AG3340 concentrations of <1 mM. AG3340 plasma concentrations in vivo, 1 h after administration, ranged from 67 to 365 nM. Thus, AG3340 produced a profound inhibition of glioma tumor growth and invasion. AG3340 markedly increased survival in this in vivo glioma model. Treatment with AG3340 may be potentially useful in

  13. Inhibition of endothelial Cdk5 reduces tumor growth by promoting non-productive angiogenesis

    PubMed Central

    Merk, Henriette; Zhang, Siwei; Lehr, Thorsten; Müller, Christoph; Ulrich, Melanie; Bibb, James A.; Adams, Ralf H.; Bracher, Franz; Zahler, Stefan; Vollmar, Angelika M.; Liebl, Johanna

    2016-01-01

    Therapeutic success of VEGF-based anti-angiogenic tumor therapy is limited due to resistance. Thus, new strategies for anti-angiogenic cancer therapy based on novel targets are urgently required. Our previous in vitro work suggested that small molecule Cdk5 inhibitors affect angiogenic processes such as endothelial migration and proliferation. Moreover, we recently uncovered a substantial role of Cdk5 in the development of lymphatic vessels. Here we pin down the in vivo impact of endothelial Cdk5 inhibition in angiogenesis and elucidate the underlying mechanism in order to judge the potential of Cdk5 as a novel anti-angiogenic and anti-cancer target. By the use of endothelial-specific Cdk5 knockout mouse models and various endothelial and tumor cell based assays including human tumor xenograft models, we show that endothelial-specific knockdown of Cdk5 results in excessive but non-productive angiogenesis during development but also in tumors, which subsequently leads to inhibition of tumor growth. As Cdk5 inhibition disrupted Notch function by reducing the generation of the active Notch intracellular domain (NICD) and Cdk5 modulates Notch-dependent endothelial cell proliferation and sprouting, we propose that the Dll4/Notch driven angiogenic signaling hub is an important and promising mechanistic target of Cdk5. In fact, Cdk5 inhibition can sensitize tumors to conventional anti-angiogenic treatment as shown in tumor xenograft models. In summary our data set the stage for Cdk5 as a drugable target to inhibit Notch-driven angiogenesis condensing the view that Cdk5 is a promising target for cancer therapy. PMID:26755662

  14. 3,4-Dihydroxybenzaldehyde Derived from Prunus mume Seed Inhibits Oxidative Stress and Enhances Estradiol Secretion in Human Ovarian Granulosa Tumor Cells.

    PubMed

    Kono, Ryohei; Nomura, Sachiko; Okuno, Yoshiharu; Nakamura, Misa; Maeno, Akihiro; Kagiya, Tomoko; Tokuda, Akihiko; Inada, Ken-Ichi; Matsuno, Akira; Utsunomiya, Tomoko; Utsunomiya, Hirotoshi

    2014-06-28

    Granulosa cells form ovarian follicles and play important roles in the growth and maturation of oocytes. The protection of granulosa cells from cellular injury caused by oxidative stress is an effective therapy for female infertility. We here investigated an effective bioactive compound derived from Prunus mume seed extract that protects granulosa cells from hydrogen peroxide (H2O2)-induced apoptosis. We detected the bioactive compound, 3,4-dihydroxybenzaldehyde (3,4-DHBA), via bioactivity-guided isolation and found that it inhibited the H2O2-induced apoptosis of granulosa cells. We also showed that 3,4-DHBA promoted estradiol secretion in granulosa cells and enhanced the mRNA expression levels of steroidogenic factor 1, a promoter of key steroidogenic enzymes. These results suggest that P. mume seed extract may have clinical potential for the prevention and treatment of female infertility. PMID:25320407

  15. Cytogenetics of human brain tumors

    SciTech Connect

    Finkernagel, S.W.; Kletz, T.; Day-Salvatore, D.L.

    1994-09-01

    Chromosome studies of 55 brain tumors, including meningiomas, gliomas, astrocyomas and pituatary adenomas, were performed. Primary and first passage cultures were successfully obtained in 75% of these samples with an average of 18 G-banded metaphases analyzed per tumor. 44% of all the brain tumors showed numerical and or structural abnormalities. 46% of the primary and 38% of the first passage cultures showed similar numerical gains/losses and complex karyotypic changes. The most frequent numerical abnormalities (n {ge} 5) included loss of chromosomes 10, 22, and Y. The structural abnormalities most often seen involved 1p, 2, 5, 7, 17q and 19. This is an ongoing study which will attempt to correlate tumor type with specific karyotypic changes and to see if any of the observed chromosomal abnormalities provide prognostic indicators.

  16. Somatostatin receptor-1 induces cell cycle arrest and inhibits tumor growth in pancreatic cancer.

    PubMed

    Li, Min; Wang, Xiaochi; Li, Wei; Li, Fei; Yang, Hui; Wang, Hao; Brunicardi, F Charles; Chen, Changyi; Yao, Qizhi; Fisher, William E

    2008-11-01

    Functional somatostatin receptors (SSTR) are lost in human pancreatic cancer. Transfection of SSTR-1 inhibited pancreatic cancer cell proliferation in vitro. We hypothesize that stable transfection of SSTR-1 may inhibit pancreatic cancer growth in vivo possibly through cell cycle arrest. In this study, we examined the expression of SSTR-1 mRNA in human pancreatic cancer tissue specimens, and investigated the effect of SSTR-1 overexpression on cell proliferation, cell cycle, and tumor growth in a subcutaneous nude mouse model. We found that SSTR-1 mRNA was downregulated in the majority of pancreatic cancer tissue specimens. Transfection of SSTR-1 caused cell cycle arrest at the G(0)/G(1) growth phase, with a corresponding decline of cells in the S (mitotic) phase. The overexpression of SSTR-1 significantly inhibited subcutaneous tumor size by 71% and 43% (n = 5, P < 0.05, Student's t-test), and inhibited tumor weight by 69% and 47% (n = 5, P < 0.05, Student's t-test), in Panc-SSTR-1 and MIA-SSTR-1 groups, respectively, indicating the potent inhibitory effect of SSTR-1 on pancreatic cancer growth. Our data demonstrate that overexpression of SSTR-1 significantly inhibits pancreatic cancer growth possibly through cell cycle arrest. This study suggests that gene therapy with SSTR-1 may be a potential adjuvant treatment for pancreatic cancer. PMID:18823376

  17. Somatostatin Receptor-1 Induces Cell Cycle Arrest and Inhibits Tumor Growth in Pancreatic Cancer

    PubMed Central

    Li, Min; Wang, Xiaochi; Li, Wei; Li, Fei; Yang, Hui; Wang, Hao; Brunicardi, F. Charles; Chen, Changyi; Yao, Qizhi; Fisher, William E.

    2010-01-01

    Functional somatostatin receptors (SSTRs) are lost in human pancreatic cancer. Transfection of SSTR-1 inhibited pancreatic cancer cell proliferation in vitro. We hypothesize that stable transfection of SSTR-1 may inhibit pancreatic cancer growth in vivo possibly through cell cycle arrest. In this study, we examined the expression of SSTR-1 mRNA in human pancreatic cancer tissue specimens, and investigated the effect of SSTR-1 overexpression on cell proliferation, cell cycle, and tumor growth in in a subcutaneous nude mouse model. We found that SSTR-1 mRNA was downregulated in the majority of pancreatic cancer tissue specimens. Transfection of SSTR-1 caused cell cycle arrest at the G0/G1 growth phase, with a corresponding decline of cells in the S (mitotic) phase. The overexpression of SSTR-1 significantly inhibited subcutaneous tumor size by 71% and 43% (n=5, p<0.05, t-test), and inhibited tumor weight by 69% and 47%, (n=5, p<0.05, t-test), in Panc-SSTR-1 and MIA-SSTR-1 groups, respectively, indicating the potent inhibitory effect of SSTR-1 on pancreatic cancer growth. Our data demonstrate that overexpression of SSTR-1 significantly inhibits pancreatic cancer growth possibly through cell cycle arrest. This study suggests that gene therapy with SSTR-1 may be a potential adjuvant treatment for pancreatic cancer. PMID:18823376

  18. Lactic Acid Bacteria Inducing a Weak Interleukin-12 and Tumor Necrosis Factor Alpha Response in Human Dendritic Cells Inhibit Strongly Stimulating Lactic Acid Bacteria but Act Synergistically with Gram-Negative Bacteria

    PubMed Central

    Zeuthen, Louise Hjerrild; Christensen, Hanne Risager; Frøkiær, Hanne

    2006-01-01

    The development and maintenance of immune homeostasis indispensably depend on signals from the gut flora. Lactic acid bacteria (LAB), which are gram-positive (G+) organisms, are plausible significant players and have received much attention. Gram-negative (G−) commensals, such as members of the family Enterobacteriaceae, may, however, be immunomodulators that are as important as G+ organisms but tend to be overlooked. Dendritic cells (DCs) are crucial immune regulators, and therefore, the present study aimed at investigating differences among human gut flora-derived LAB and G− bacteria in their patterns of DC polarization. Human monocyte-derived DCs were exposed to UV-killed bacteria, and cytokine secretion and surface marker expression were analyzed. Profound differences in the DC polarization patterns were found among the strains. While strains of LAB varied greatly in their capacity to induce interleukin-12 (IL-12) and tumor necrosis factor alpha (TNF-α), G− strains were consistently weak IL-12 and TNF-α inducers. All strains induced significant amounts of IL-10, but G− bacteria were far more potent IL-10 inducers than LAB. Interestingly, we found that when weakly IL-12- and TNF-α-inducing LAB and strong IL-12- and TNF-α-inducing LAB were mixed, the weakly IL-12- and TNF-α-inducing LAB efficiently inhibited otherwise strong IL-12- and TNF-α-inducing LAB, yet when weakly IL-12- and TNF-α-inducing LAB were mixed with G− bacteria, they synergistically induced IL-12 and TNF-α. Furthermore, strong IL-12- and TNF-α-inducing LAB efficiently up-regulated surface markers (CD40, CD83, CD86, and HLA-DR), which were inhibited by weakly IL-12- and TNF-α-inducing LAB. All G− bacteria potently up-regulated surface markers; however, these markers were not inhibited by weakly IL-12- and TNF-α-inducing LAB. These much divergent DC stimulation patterns among intestinal bacteria, which encompass both antagonistic and synergistic relationships, support the

  19. Synergistic tumor suppression by combined inhibition of telomerase and CDKN1A

    PubMed Central

    Gupta, Romi; Dong, Yuying; Solomon, Peter D.; Wettersten, Hiromi I.; Cheng, Christopher J.; Min, JIn-Na; Henson, Jeremy; Dogra, Shaillay Kumar; Hwang, Sung H.; Hammock, Bruce D.; Zhu, Lihua J.; Reddel, Roger R.; Saltzman, W. Mark; Weiss, Robert H.; Chang, Sandy; Green, Michael R.; Wajapeyee, Narendra

    2014-01-01

    Tumor suppressor p53 plays an important role in mediating growth inhibition upon telomere dysfunction. Here, we show that loss of the p53 target gene cyclin-dependent kinase inhibitor 1A (CDKN1A, also known as p21WAF1/CIP1) increases apoptosis induction following telomerase inhibition in a variety of cancer cell lines and mouse xenografts. This effect is highly specific to p21, as loss of other checkpoint proteins and CDK inhibitors did not affect apoptosis. In telomerase, inhibited cell loss of p21 leads to E2F1- and p53-mediated transcriptional activation of p53-upregulated modulator of apoptosis, resulting in increased apoptosis. Combined genetic or pharmacological inhibition of telomerase and p21 synergistically suppresses tumor growth. Furthermore, we demonstrate that simultaneous inhibition of telomerase and p21 also suppresses growth of tumors containing mutant p53 following pharmacological restoration of p53 activity. Collectively, our results establish that inactivation of p21 leads to increased apoptosis upon telomerase inhibition and thus identify a genetic vulnerability that can be exploited to treat many human cancers containing either wild-type or mutant p53. PMID:25024194

  20. Drugs Which Inhibit Osteoclast Function Suppress Tumor Growth through Calcium Reduction in Bone

    PubMed Central

    Li, Xin; Liao, Jinhui; Park, Serk In; Koh, Amy J; Sadler, William D; Pienta, Kenneth J; Rosol, Thomas J; McCauley, Laurie K

    2011-01-01

    Prostate carcinoma frequently metastasizes to bone where the microenvironment facilitates its growth. Inhibition of bone resorption is effective in reducing tumor burden and bone destruction in prostate cancer. However, whether drugs that inhibit osteoclast function inhibit tumor growth independent of inhibition of bone resorption is unclear. Calcium is released during bone resorption and the calcium sensing receptor is an important regulator of cancer cell proliferation. The goal of this investigation was to elucidate the role of calcium released during bone resorption and to determine the impact of drugs which suppress bone resorption on tumor growth in bone. To compare tumor growth in a skeletal versus non-skeletal site, equal numbers of canine prostate cancer cells expressing luciferase (ACE-1luc) prostate cancer cells were inoculated into a simple collagen matrix, neonatal mouse vertebrae (vossicles), human de-proteinized bone, or a mineralized collagen matrix. Implants were placed subcutaneously into athymic mice. Luciferase activity was used to track tumor growth weekly and at one month tumors were dissected for histologic analysis. Luciferase activity and tumor size were greater in vossicles, de-proteinized bone and mineralized collagen matrix versus non-mineralized collagen implants. The human osteoblastic prostate carcinoma cell line C4-2b also grew better in a mineral rich environment with a greater proliferation of C4-2b cells reflected by Ki-67 staining. Zoledronic acid (ZA), a bisphosphonate, and recombinant OPG-Fc, a RANKL inhibitor, were administered to mice bearing vertebral implants (vossicles) containing ACE-1 osteoblastic prostate cancer cells. Vossicles or collagen matrices were seeded with ACE-1luc cells subcutaneously in athymic mice (2 vossicles, 2 collagen implants/mouse). Mice received ZA (5μg/mouse, twice/week), (OPG-Fc at 10mg/kg, 3 times/week) or vehicle, and luciferase activity was measured weekly. Histologic analysis of the tumors

  1. Ozone selectively inhibits growth of human cancer cells

    SciTech Connect

    Sweet, F.; Kao, M.S.; Lee, S.C.; Hagar, W.L.; Sweet, W.E.

    1980-08-01

    The growth of human cancer cells from lung, breast, and uterine tumors was selectively inhibited in a dose-dependent manner by ozone at 0.3 to 0.8 part per million of ozone in ambient air during 8 days of culture. Human lung diploid fibroblasts served as noncancerous control cells. The presence of ozone at 0.3 to 0.5 part per million inhibited cancer cell growth 40 and 60 percent, respectively. The noncancerous lung cells were unaffected at these levels. Exposure to ozone at 0.8 part per million inhibited cancer cell growth more than 90 percent and control cell growth less than 50 percent. Evidently, the mechanisms for defense against ozone damage are impaired in human cancer cells.

  2. Low-molecular-weight fractions of Alcalase hydrolyzed egg ovomucin extract exert anti-inflammatory activity in human dermal fibroblasts through the inhibition of tumor necrosis factor-mediated nuclear factor κB pathway.

    PubMed

    Sun, Xiaohong; Chakrabarti, Subhadeep; Fang, Jun; Yin, Yulong; Wu, Jianping

    2016-07-01

    Ovomucin is a mucin-like protein from egg white with a variety of biological functions. We hypothesized that ovomucin-derived peptides might exert anti-inflammatory activity. The specific objectives were to test the anti-inflammatory activities of different ovomucin hydrolysates and its various fractions in human dermal fibroblasts, and to understand the possible molecular mechanisms. Three ovomucin hydrolysates were prepared and desalted; only the desalted Alcalase hydrolysate showed anti-inflammatory activity. Desalting of ovomucin hydrolysate enriched the proportion of low-molecular-weight (MW) peptides. Indeed, ultrafiltration of this hydrolysate displayed comparable anti-inflammatory activity in dermal fibroblasts, indicating the responsible role of low-MW bioactive peptides in exerting the beneficial biological function. The anti-inflammatory activity of low-MW peptides was regulated through the inhibition of tumor necrosis factor-mediated nuclear factor κ-light-chain-enhancer of activated B cells activity. Our study demonstrated that both peptide composition and MW distribution play important roles in anti-inflammatory activity. The low-MW fractions prepared from ovomucin Alcalase hydrolysate may have potential applications for maintenance of dermal health and treatment of skin diseases. PMID:27333955

  3. Downregulation of tetrahydrobiopterin inhibits tumor angiogenesis in BALB/c-nu mice with hepatocellular carcinoma

    PubMed Central

    Dai, Youguo; Cui, Jin; Gan, Ping; Li, Weiming

    2016-01-01

    Hepatocellular carcinoma (HCC) is a highly vascular tumor, and treatment options for patients of advanced-stage are limited. Nitric oxide (NO), which is derived from endothelial nitric oxide synthase (eNOS), provides crucial signals for angiogenesis in the tumor microenvironment. Tetrahydrobiopterin (BH4) is an essential cofactor eNOS and represents a critical determinant of NO production. To examine whether treatment of 2,4-diamino-6-hydroxypyrimidine (DAHP) inhibits angiogenesis of HCC, BALB/c-nu mice were injected with HepG-2 cells with DAHP. Supplemental DAHP treatment decreased K-ras mRNA transcripts, inhibition of phosphorylation of eNOS and Akt, inhibition of guanosine triphosphate cyclohydrolase (GTPCH), and decreased significantly NO synthesis, and then inhibited angiogenesis, compared with the results observed in the saline group. Histopathology demonstrated angiogenesis and tumor formation were significantly inhibited in HCC. DAHP downregulates GTPCH protein expression, corresponding to decreased levels of BH4 and the contents of NO. In addition, DAHP downregulates eNOS and Akt protein expression, corresponding to decreased eNOS phosphorylation at Ser1177 and Akt phosphorylation, compared with the saline control. We suggest that DAHP, recognized as a specific competitive inhibitor of GTPCH, can decrease tumor BH4 and NO by the inhibition of the wild-type Ras-PI3K/Akt pathway, and then inhibiting angiogenesis, and may provide a novel and promising way to target BH4 synthetic pathways to inhibit angiogenesis and to control potential progression of HCC. Whether DAHP has a therapeutic potential will require more direct testing in humans. PMID:27279530

  4. Inhibition of apoptosis as a mechanism of tumor promotion.

    PubMed

    Wright, S C; Zhong, J; Larrick, J W

    1994-06-01

    Recent evidence supports the concept that tumor growth in vivo depends on evasion of normal homeostatic control mechanisms that operate through induction of cell death by apoptosis. This study tested the hypothesis that a common property shared by known or suspected tumor promoters is the ability to block the process of apoptosis. A total of 10 tumor promoters were tested and all were found to inhibit DNA fragmentation and cell death of 7 different cell lines triggered into apoptosis by diverse agents. Resistance to apoptosis could be induced rapidly (within 1 h) by treating with relatively high concentrations of promoters. However, low physiological concentrations of promoters could also induce complete resistance to apoptosis after prolonged exposure (5-15 days of culture). Like tumor promotion in vivo, promoter-induced resistance to apoptosis was reversible after culturing in the absence of promoter. These findings provide new insight into the mechanism of tumor promotion and suggest a novel in vitro screening assay to detect new tumor-promoting agents in the environment. PMID:8005393

  5. BmKCT toxin inhibits glioma proliferation and tumor metastasis.

    PubMed

    Fan, Shaozhong; Sun, Zhengbo; Jiang, Dahe; Dai, Chao; Ma, Yibao; Zhao, Zhenhuan; Liu, Hui; Wu, Yingliang; Cao, Zhijian; Li, Wenxin

    2010-05-28

    Malignant gliomas are the most common primary brain tumors associated with significant morbidity and mortality. How to target the tumor in situ, and inhibit tumor cell proliferation and invasion is the key for therapy. Gliomas express a glioma-specific chloride ion channel that is sensitive to toxins including BmKCT. In the current study, the inhibitory effect of BmKCT on glioma growth was observed in vivo using the glioma/SD rat model. Furthermore, BmKCT prevented the metastasis of glioma cells in vivo. Moreover, biodistribution experiments with (l3l)I-labeled or Cy5.5-conjugated BmKCT revealed that BmKCT selectively targeted the glioma in situ. Our data suggest that BmKCT could be exploited as a potential therapeutic for glioma diagnosis and therapy. PMID:19906483

  6. 2-Methoxycinnamaldehyde inhibits tumor angiogenesis by suppressing Tie2 activation.

    PubMed

    Yamakawa, Daishi; Kidoya, Hiroyasu; Sakimoto, Susumu; Jia, Weizhen; Takakura, Nobuyuki

    2011-11-11

    Blood vessels are mainly composed of intraluminal endothelial cells (ECs) and mural cells adhering to the ECs on their basal side. Immature blood vessels lacking mural cells are leaky; thus, the process of mural cell adhesion to ECs is indispensable for stability of the vessels during physiological angiogenesis. However, in the tumor microenvironment, although some blood vessels are well-matured, the majority is immature. Because mural cell adhesion to ECs also has a marked anti-apoptotic effect, angiogenesis inhibitors that destroy immature blood vessels may not affect mature vessels showing more resistance to apoptosis. Activation of Tie2 receptor tyrosine kinase expressed in ECs mediates pro-angiogenic effects via the induction of EC migration but also facilitates vessel maturation via the promotion of cell adhesion between mural cells and ECs. Therefore, inhibition of Tie2 has the advantage of completely inhibiting angiogenesis. Here, we isolated a novel small molecule Tie2 kinase inhibitor, identified as 2-methoxycinnamaldehyde (2-MCA). We found that 2-MCA inhibits both sprouting angiogenesis and maturation of blood vessels, resulting in inhibition of tumor growth. Our results suggest a potent clinical benefit of disrupting these two using Tie2 inhibitors. PMID:22033407

  7. Inhibition of PAI-1 Limits Tumor Angiogenesis Regardless of Angiogenic Stimuli in Malignant Pleural Mesothelioma.

    PubMed

    Takayama, Yusuke; Hattori, Noboru; Hamada, Hironobu; Masuda, Takeshi; Omori, Keitaro; Akita, Shin; Iwamoto, Hiroshi; Fujitaka, Kazunori; Kohno, Nobuoki

    2016-06-01

    Malignant pleural mesothelioma (MPM) is an aggressive malignant tumor that secretes various angiogenic factors. The main inhibitor of plasminogen activators, PAI-1 (SERPINE1), has been implicated in tumor progression and angiogenesis, and high PAI-1 expression has been associated with poor prognosis in MPM patients. In this study, we examined the antiangiogenic effects of PAI-1 inhibition in MPM. We administered the PAI-1 inhibitor, SK-216, to orthotopic mouse models in which MPM cells expressing high levels of VEGF (VEGFA) or bFGF (FGF2) were intrapleurally transplanted. SK-216 administration reduced tumor weights and the degree of angiogenesis in intrapleural tumors, irrespective of their angiogenic expression profiles. In addition, a combination of SK-216 and the chemotherapeutic agent cisplatin significantly reduced tumor weights compared with monotherapy, prolonging the survival of animals compared with cisplatin treatment alone. Furthermore, SK-216 inhibited migration and tube formation of cultured human umbilical vein endothelial cells induced by various angiogenic factors known to be secreted by MPM. These findings suggest that PAI-1 inactivation by SK-216 may represent a general strategy for inhibiting angiogenesis, including for the treatment of MPM. Cancer Res; 76(11); 3285-94. ©2016 AACR. PMID:27197170

  8. Kalkitoxin Inhibits Angiogenesis, Disrupts Cellular Hypoxic Signaling, and Blocks Mitochondrial Electron Transport in Tumor Cells

    PubMed Central

    Morgan, J. Brian; Liu, Yang; Coothankandaswamy, Veena; Mahdi, Fakhri; Jekabsons, Mika B.; Gerwick, William H.; Valeriote, Frederick A.; Zhou, Yu-Dong; Nagle, Dale G.

    2015-01-01

    The biologically active lipopeptide kalkitoxin was previously isolated from the marine cyanobacterium Moorea producens (Lyngbya majuscula). Kalkitoxin exhibited N-methyl-d-aspartate (NMDA)-mediated neurotoxicity and acted as an inhibitory ligand for voltage-sensitive sodium channels in cultured rat cerebellar granule neurons. Subsequent studies revealed that kalkitoxin generated a delayed form of colon tumor cell cytotoxicity in 7-day clonogenic cell survival assays. Cell line- and exposure time-dependent cytostatic/cytotoxic effects were previously observed with mitochondria-targeted inhibitors of hypoxia-inducible factor-1 (HIF-1). The transcription factor HIF-1 functions as a key regulator of oxygen homeostasis. Therefore, we investigated the ability of kalkitoxin to inhibit hypoxic signaling in human tumor cell lines. Kalkitoxin potently and selectively inhibited hypoxia-induced activation of HIF-1 in T47D breast tumor cells (IC50 5.6 nM). Mechanistic studies revealed that kalkitoxin inhibits HIF-1 activation by suppressing mitochondrial oxygen consumption at electron transport chain (ETC) complex I (NADH-ubiquinone oxidoreductase). Further studies indicate that kalkitoxin targets tumor angiogenesis by blocking the induction of angiogenic factors (i.e., VEGF) in tumor cells. PMID:25803180

  9. Inhibition of DNA methylation promotes breast tumor sensitivity to netrin-1 interference.

    PubMed

    Grandin, Mélodie; Mathot, Pauline; Devailly, Guillaume; Bidet, Yannick; Ghantous, Akram; Favrot, Clementine; Gibert, Benjamin; Gadot, Nicolas; Puisieux, Isabelle; Herceg, Zdenko; Delcros, Jean-Guy; Bernet, Agnès; Mehlen, Patrick; Dante, Robert

    2016-01-01

    In a number of human cancers, NTN1 upregulation inhibits apoptosis induced by its so-called dependence receptors DCC and UNC5H, thus promoting tumor progression. In other cancers however, the selective inhibition of this dependence receptor death pathway relies on the silencing of pro-apoptotic effector proteins. We show here that a substantial fraction of human breast tumors exhibits simultaneous DNA methylation-dependent loss of expression of NTN1 and of DAPK1, a serine threonine kinase known to transduce the netrin-1 dependence receptor pro-apoptotic pathway. The inhibition of DNA methylation by drugs such as decitabine restores the expression of both NTN1 and DAPK1 in netrin-1-low cancer cells. Furthermore, a combination of decitabine with NTN1 silencing strategies or with an anti-netrin-1 neutralizing antibody potentiates tumor cell death and efficiently blocks tumor growth in different animal models. Thus, combining DNA methylation inhibitors with netrin-1 neutralizing agents may be a valuable strategy for combating cancer. PMID:27378792

  10. Inhibition of Ovarian Tumor Growth by Targeting the HU177 Cryptic Collagen Epitope.

    PubMed

    Caron, Jennifer M; Ames, Jacquelyn J; Contois, Liangru; Liebes, Leonard; Friesel, Robert; Muggia, Franco; Vary, Calvin P H; Oxburgh, Leif; Brooks, Peter C

    2016-06-01

    Evidence suggests that stromal cells play critical roles in tumor growth. Uncovering new mechanisms that control stromal cell behavior and their accumulation within tumors may lead to development of more effective treatments. We provide evidence that the HU177 cryptic collagen epitope is selectively generated within human ovarian carcinomas and this collagen epitope plays a role in SKOV-3 ovarian tumor growth in vivo. The ability of the HU177 epitope to regulate SKOV-3 tumor growth depends in part on its ability to modulate stromal cell behavior because targeting this epitope inhibited angiogenesis and, surprisingly, the accumulation of α-smooth muscle actin-expressing stromal cells. Integrin α10β1 can serve as a receptor for the HU177 epitope in α-smooth muscle actin-expressing stromal cells and subsequently regulates Erk-dependent migration. These findings are consistent with a mechanism by which the generation of the HU177 collagen epitope provides a previously unrecognized α10β1 ligand that selectively governs angiogenesis and the accumulation of stromal cells, which in turn secrete protumorigenic factors that contribute to ovarian tumor growth. Our findings provide a new mechanistic understanding into the roles by which the HU177 epitope regulates ovarian tumor growth and provide new insight into the clinical results from a phase 1 human clinical study of the monoclonal antibody D93/TRC093 in patients with advanced malignant tumors. PMID:27216148

  11. Tumor necrosis factor-alpha inhibits stem cell factor-induced proliferation of human bone marrow progenitor cells in vitro. Role of p55 and p75 tumor necrosis factor receptors.

    PubMed Central

    Rusten, L S; Smeland, E B; Jacobsen, F W; Lien, E; Lesslauer, W; Loetscher, H; Dubois, C M; Jacobsen, S E

    1994-01-01

    Stem cell factor (SCF), a key regulator of hematopoiesis, potently synergizes with a number of hematopoietic growth factors. However, little is known about growth factors capable of inhibiting the actions of SCF. TNF-alpha has been shown to act as a bidirectional regulator of myeloid cell proliferation and differentiation. This study was designed to examine interactions between TNF-alpha and SCF. Here, we demonstrate that TNF-alpha potently and directly inhibits SCF-stimulated proliferation of CD34+ hematopoietic progenitor cells. Furthermore, TNF-alpha blocked all colony formation stimulated by SCF in combination with granulocyte colony-stimulating factor (CSF) or CSF-1. The synergistic effect of SCF observed in combination with GM-CSF or IL-3 was also inhibited by TNF-alpha, resulting in colony numbers similar to those obtained in the absence of SCF. These effects of TNF-alpha were mediated through the p55 TNF receptor, whereas little or no inhibition was signaled through the p75 TNF receptor. Finally, TNF-alpha downregulated c-kit cell-surface expression on CD34+ bone marrow cells, and this was predominantly a p55 TNF receptor-mediated event as well. Images PMID:7518828

  12. Sesquiterpenoid Lactones in Tanacetum huronense Inhibit Human Glioblastoma Cell Proliferation.

    PubMed

    Dissanayake, Amila A; Bejcek, Bruce E; Zhang, Chuan-Rui; Nair, Muraleedharan G

    2016-05-01

    Tanacetum huronense (Lake Huron tansy), which is native to the upper Midwest region of USA and Canada, was examined for the presence of anticancer compounds using an in vitro human tumor cell proliferation inhibition assay, with glioblastoma derived cell line U-87 MG. Bioassay-directed purification of the ethyl acetate extract of the aerial portion of this plant identified six active sesquiterpenoid lactones (1-6). Among these, compounds 5 and 6 are new structural analogs. One of the most abundant isolates, tanacin (4), exhibited the greatest inhibition with an IC50 value of 4.5 μg/mL. PMID:27319121

  13. Bursts of Bipolar Microsecond Pulses Inhibit Tumor Growth

    PubMed Central

    Sano, Michael B.; Arena, Christopher B.; Bittleman, Katelyn R.; DeWitt, Matthew R.; Cho, Hyung J.; Szot, Christopher S.; Saur, Dieter; Cissell, James M.; Robertson, John; Lee, Yong W.; Davalos, Rafael V.

    2015-01-01

    Irreversible electroporation (IRE) is an emerging focal therapy which is demonstrating utility in the treatment of unresectable tumors where thermal ablation techniques are contraindicated. IRE uses ultra-short duration, high-intensity monopolar pulsed electric fields to permanently disrupt cell membranes within a well-defined volume. Though preliminary clinical results for IRE are promising, implementing IRE can be challenging due to the heterogeneous nature of tumor tissue and the unintended induction of muscle contractions. High-frequency IRE (H-FIRE), a new treatment modality which replaces the monopolar IRE pulses with a burst of bipolar pulses, has the potential to resolve these clinical challenges. We explored the pulse-duration space between 250 ns and 100 μs and determined the lethal electric field intensity for specific H-FIRE protocols using a 3D tumor mimic. Murine tumors were exposed to 120 bursts, each energized for 100 μs, containing individual pulses 1, 2, or 5 μs in duration. Tumor growth was significantly inhibited and all protocols were able to achieve complete regressions. The H-FIRE protocol substantially reduces muscle contractions and the therapy can be delivered without the need for a neuromuscular blockade. This work shows the potential for H-FIRE to be used as a focal therapy and merits its investigation in larger pre-clinical models. PMID:26459930

  14. Bursts of Bipolar Microsecond Pulses Inhibit Tumor Growth

    NASA Astrophysics Data System (ADS)

    Sano, Michael B.; Arena, Christopher B.; Bittleman, Katelyn R.; Dewitt, Matthew R.; Cho, Hyung J.; Szot, Christopher S.; Saur, Dieter; Cissell, James M.; Robertson, John; Lee, Yong W.; Davalos, Rafael V.

    2015-10-01

    Irreversible electroporation (IRE) is an emerging focal therapy which is demonstrating utility in the treatment of unresectable tumors where thermal ablation techniques are contraindicated. IRE uses ultra-short duration, high-intensity monopolar pulsed electric fields to permanently disrupt cell membranes within a well-defined volume. Though preliminary clinical results for IRE are promising, implementing IRE can be challenging due to the heterogeneous nature of tumor tissue and the unintended induction of muscle contractions. High-frequency IRE (H-FIRE), a new treatment modality which replaces the monopolar IRE pulses with a burst of bipolar pulses, has the potential to resolve these clinical challenges. We explored the pulse-duration space between 250 ns and 100 μs and determined the lethal electric field intensity for specific H-FIRE protocols using a 3D tumor mimic. Murine tumors were exposed to 120 bursts, each energized for 100 μs, containing individual pulses 1, 2, or 5 μs in duration. Tumor growth was significantly inhibited and all protocols were able to achieve complete regressions. The H-FIRE protocol substantially reduces muscle contractions and the therapy can be delivered without the need for a neuromuscular blockade. This work shows the potential for H-FIRE to be used as a focal therapy and merits its investigation in larger pre-clinical models.

  15. Bursts of Bipolar Microsecond Pulses Inhibit Tumor Growth.

    PubMed

    Sano, Michael B; Arena, Christopher B; Bittleman, Katelyn R; DeWitt, Matthew R; Cho, Hyung J; Szot, Christopher S; Saur, Dieter; Cissell, James M; Robertson, John; Lee, Yong W; Davalos, Rafael V

    2015-01-01

    Irreversible electroporation (IRE) is an emerging focal therapy which is demonstrating utility in the treatment of unresectable tumors where thermal ablation techniques are contraindicated. IRE uses ultra-short duration, high-intensity monopolar pulsed electric fields to permanently disrupt cell membranes within a well-defined volume. Though preliminary clinical results for IRE are promising, implementing IRE can be challenging due to the heterogeneous nature of tumor tissue and the unintended induction of muscle contractions. High-frequency IRE (H-FIRE), a new treatment modality which replaces the monopolar IRE pulses with a burst of bipolar pulses, has the potential to resolve these clinical challenges. We explored the pulse-duration space between 250 ns and 100 μs and determined the lethal electric field intensity for specific H-FIRE protocols using a 3D tumor mimic. Murine tumors were exposed to 120 bursts, each energized for 100 μs, containing individual pulses 1, 2, or 5 μs in duration. Tumor growth was significantly inhibited and all protocols were able to achieve complete regressions. The H-FIRE protocol substantially reduces muscle contractions and the therapy can be delivered without the need for a neuromuscular blockade. This work shows the potential for H-FIRE to be used as a focal therapy and merits its investigation in larger pre-clinical models. PMID:26459930

  16. Paracrine expression of a native soluble vascular endothelial growth factor receptor inhibits tumor growth, metastasis, and mortality rate

    PubMed Central

    Goldman, Corey K.; Kendall, Richard L.; Cabrera, Gustavo; Soroceanu, Liliana; Heike, Yuji; Gillespie, G. Yancey; Siegal, Gene P.; Mao, Xianzhi; Bett, Andrew J.; Huckle, William R.; Thomas, Kenneth A.; Curiel, David T.

    1998-01-01

    Vascular endothelial growth factor (VEGF) is a potent and selective vascular endothelial cell mitogen and angiogenic factor. VEGF expression is elevated in a wide variety of solid tumors and is thought to support their growth by enhancing tumor neovascularization. To block VEGF-dependent angiogenesis, tumor cells were transfected with cDNA encoding the native soluble FLT-1 (sFLT-1) truncated VEGF receptor which can function both by sequestering VEGF and, in a dominant negative fashion, by forming inactive heterodimers with membrane-spanning VEGF receptors. Transient transfection of HT-1080 human fibrosarcoma cells with a gene encoding sFLT-1 significantly inhibited their implantation and growth in the lungs of nude mice following i.v. injection and their growth as nodules from cells injected s.c. High sFLT-1 expressing stably transfected HT-1080 clones grew even slower as s.c. tumors. Finally, survival was significantly prolonged in mice injected intracranially with human glioblastoma cells stably transfected with the sflt-1 gene. The ability of sFLT-1 protein to inhibit tumor growth is presumably attributable to its paracrine inhibition of tumor angiogenesis in vivo, since it did not affect tumor cell mitogenesis in vitro. These results not only support VEGF receptors as antiangiogenic targets but also demonstrate that sflt-1 gene therapy might be a feasible approach for inhibiting tumor angiogenesis and growth. PMID:9671758

  17. ICAM-1 suppresses tumor metastasis by inhibiting macrophage M2 polarization through blockade of efferocytosis.

    PubMed

    Yang, M; Liu, J; Piao, C; Shao, J; Du, J

    2015-01-01

    Efficient clearance of apoptotic cells (efferocytosis) can profoundly influence tumor-specific immunity. Tumor-associated macrophages are M2-polarized macrophages that promote key processes in tumor progression. Efferocytosis stimulates M2 macrophage polarization and contributes to cancer metastasis, but the signaling mechanism underlying this process is unclear. Intercellular cell adhesion molecule-1 (ICAM-1) is a transmembrane glycoprotein member of the immunoglobulin superfamily, which has been implicated in mediating cell-cell interaction and outside-in cell signaling during the immune response. We report that ICAM-1 expression is inversely associated with macrophage infiltration and the metastasis index in human colon tumors by combining Oncomine database analysis and immunohistochemistry for ICAM-1. Using a colon cancer liver metastasis model in ICAM-1-deficient (ICAM-1(-/-)) mice and their wild-type littermates, we found that loss of ICAM-1 accelerated liver metastasis of colon carcinoma cells. Moreover, ICAM-1 deficiency increased M2 macrophage polarization during tumor progression. We further demonstrated that ICAM-1 deficiency in macrophages led to promotion of efferocytosis of apoptotic tumor cells through activation of the phosphatidylinositol 3 kinase/Akt signaling pathway. More importantly, coculture of ICAM-1(-/-) macrophages with apoptotic cancer cells resulted in an increase of M2-like macrophages, which was blocked by an efferocytosis inhibitor. Our findings demonstrate a novel role for ICAM-1 in suppressing M2 macrophage polarization via downregulation of efferocytosis in the tumor microenvironment, thereby inhibiting metastatic tumor progression. PMID:26068788

  18. Systemic miRNA-7 delivery inhibits tumor angiogenesis and growth in murine xenograft glioblastoma

    PubMed Central

    Van Beijnum, Judy R.; Cerisoli, Francesco; Scaria, Puthupparampil V.; Verheul, Mark; Van Berkel, Maaike P.; Pieters, Ebel H. E.; Van Haastert, Rick J.; Yousefi, Afrouz; Mastrobattista, Enrico; Storm, Gert; Berezikov, Eugene; Cuppen, Edwin; Woodle, Martin; Schaapveld, Roel Q. J.; Prevost, Gregoire P.; Griffioen, Arjan W.; Van Noort, Paula I.; Schiffelers, Raymond M.

    2014-01-01

    Tumor-angiogenesis is the multi-factorial process of sprouting of endothelial cells (EC) into micro-vessels to provide tumor cells with nutrients and oxygen. To explore miRNAs as therapeutic angiogenesis-inhibitors, we performed a functional screen to identify miRNAs that are able to decrease EC viability. We identified miRNA-7 (miR-7) as a potent negative regulator of angiogenesis. Introduction of miR-7 in EC resulted in strongly reduced cell viability, tube formation, sprouting and migration. Application of miR-7 in the chick chorioallantoic membrane assay led to a profound reduction of vascularization, similar to anti-angiogenic drug sunitinib. Local administration of miR-7 in an in vivo murine neuroblastoma tumor model significantly inhibited angiogenesis and tumor growth. Finally, systemic administration of miR-7 using a novel integrin-targeted biodegradable polymeric nanoparticles that targets both EC and tumor cells, strongly reduced angiogenesis and tumor proliferation in mice with human glioblastoma xenografts. Transcriptome analysis of miR-7 transfected EC in combination with in silico target prediction resulted in the identification of OGT as novel target gene of miR-7. Our study provides a comprehensive validation of miR-7 as novel anti-angiogenic therapeutic miRNA that can be systemically delivered to both EC and tumor cells and offers promise for miR-7 as novel anti-tumor therapeutic. PMID:25149532

  19. Compromised GABAergic inhibition contributes to tumor-associated epilepsy.

    PubMed

    MacKenzie, Georgina; O'Toole, Kate K; Moss, Stephen J; Maguire, Jamie

    2016-10-01

    Glioblastoma Multiforme (GBM) is the most common form of primary brain tumor with 30-50% of patients presenting with epilepsy. These tumor-associated seizures are often resistant to traditional antiepileptic drug treatment and persist after tumor resection. This suggests that changes in the peritumoral tissue underpin epileptogenesis. It is known that glioma cells extrude pathological concentrations of glutamate which is thought to play a role in tumor progression and the development of epilepsy. Given that pathological concentrations of glutamate have been shown to dephosphorylate and downregulate the potassium chloride cotransporter KCC2, we hypothesized that glioma-induced alterations in KCC2 in the peritumoral region may play a role in tumor-associated epilepsy. Consistent with this hypothesis, we observe a decrease in total KCC2 expression and a dephosphorylation of KCC2 at residue Ser940 in a glioma model which exhibits hyperexcitability and the development of spontaneous seizures. To determine whether the reduction of KCC2 could potentially contribute to tumor-associated epilepsy, we generated mice with a focal knockdown of KCC2 by injecting AAV2-Cre-GFP into the cortex of floxed KCC2 mice. The AAV2-Cre-mediated knockdown of KCC2 was sufficient to induce the development of spontaneous seizures. Further, blocking NKCC1 with bumetanide to offset the loss of KCC2 reduced the seizure susceptibility in glioma-implanted mice. These findings support a mechanism of tumor-associated epilepsy involving downregulation of KCC2 in the peritumoral region leading to compromised GABAergic inhibition and suggest that modulating chloride homeostasis may be useful for seizure control. PMID:27513374

  20. CDC42 inhibition suppresses progression of incipient intestinal tumors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mutations in the APC or Beta-catenin genes are well-established initiators of colorectal cancer, yet modifiers that facilitate the survival and progression of nascent tumor cells are not well defined. Using genetic and pharmacologic approaches in mouse colorectal cancer and human colorectal cancer x...

  1. Casiopeina II-gly and bromo-pyruvate inhibition of tumor hexokinase, glycolysis, and oxidative phosphorylation.

    PubMed

    Marín-Hernández, Alvaro; Gallardo-Pérez, Juan Carlos; López-Ramírez, Sayra Y; García-García, Jorge Donato; Rodríguez-Zavala, José Salud; Ruiz-Ramírez, Lena; Gracia-Mora, Isabel; Zentella-Dehesa, Alejandro; Sosa-Garrocho, Marcela; Macías-Silva, Marina; Moreno-Sánchez, Rafael; Rodríguez-Enríquez, Sara

    2012-05-01

    The copper-based drug Casiopeina II-gly (CasII-gly) shows potent antineoplastic effect and diminishes mitochondrial metabolism on several human and rodent malignant tumors. To elucidate whether CasII-gly also affects glycolysis, (a) the flux through the complete pathway and the initial segment and (b) the activities of several glycolytic enzymes of AS-30D hepatocarcinoma cells were determined. CasII-gly (IC₅₀ = 0.74-6.7 μM) was more effective to inhibit 24-72 h growth of several human carcinomas than 3-bromopyruvate (3BrPyr) (IC₅₀ = 45-100 μM) with no apparent effect on normal human-proliferating lymphocytes and HUVECs. In short-term 60-min experiments, CasII-gly increased tumor cell lactate production and glycogen breakdown. CasII-gly was 1.3-21 times more potent than 3BrPyr and cisplatin to inhibit tumor HK. As CasII-gly inhibited the soluble and mitochondrial HK activities and the flux through the HK-TPI glycolytic segment, whereas PFK-1, GAPDH, PGK, PYK activities and HPI-TPI segment flux were not affected, the data suggested glycogenolysis activation induced by HK inhibition. Accordingly, glycogen-depleted as well as oligomycin-treated cancer cells became more sensitive to CasII-gly. The inhibition time-course of HK by CasII-gly was slower than that of OxPhos in AS-30D cells, indicating that glycolytic toxicity was secondary to mitochondria, the primary CasII-gly target. In long-term 24-h experiments with HeLa cells, 5 μM CasII-gly inhibited OxPhos (80%), glycolysis (40%), and HK (42%). The present data indicated that CasII-gly is an effective multisite anticancer drug simultaneously targeting mitochondria and glycolysis. PMID:22349057

  2. Dopamine D2 receptor agonists inhibit lung cancer progression by reducing angiogenesis and tumor infiltrating myeloid derived suppressor cells.

    PubMed

    Hoeppner, Luke H; Wang, Ying; Sharma, Anil; Javeed, Naureen; Van Keulen, Virginia P; Wang, Enfeng; Yang, Ping; Roden, Anja C; Peikert, Tobias; Molina, Julian R; Mukhopadhyay, Debabrata

    2015-01-01

    We sought to determine whether Dopamine D2 Receptor (D2R) agonists inhibit lung tumor progression and identify subpopulations of lung cancer patients that benefit most from D2R agonist therapy. We demonstrate D2R agonists abrogate lung tumor progression in syngeneic (LLC1) and human xenograft (A549) orthotopic murine models through inhibition of tumor angiogenesis and reduction of tumor infiltrating myeloid derived suppressor cells. Pathological examination of human lung cancer tissue revealed a positive correlation between endothelial D2R expression and tumor stage. Lung cancer patients with a smoking history exhibited greater levels of D2R in lung endothelium. Our results suggest D2R agonists may represent a promising individualized therapy for lung cancer patients with high levels of endothelial D2R expression and a smoking history. PMID:25226814

  3. Dopamine D2 Receptor Agonists Inhibit Lung Cancer Progression by Reducing Angiogenesis and Tumor Infiltrating Myeloid Derived Suppressor Cells

    PubMed Central

    Hoeppner, Luke H.; Wang, Ying; Sharma, Anil; Javeed, Naureen; Van Keulen, Virginia P.; Wang, Enfeng; Yang, Ping; Roden, Anja C.; Peikert, Tobias; Molina, Julian R.; Mukhopadhyay, Debabrata

    2014-01-01

    We sought to determine whether Dopamine D2 Receptor (D2R) agonists inhibit lung tumor progression and identify subpopulations of lung cancer patients that benefit most from D2R agonist therapy. We demonstrate D2R agonists abrogate lung tumor progression in syngeneic (LLC1) and human xenograft (A549) orthotopic murine models through inhibition of tumor angiogenesis and reduction of tumor infiltrating myeloid derived suppressor cells. Pathological examination of human lung cancer tissue revealed a positive correlation between endothelial D2R expression and tumor stage. Lung cancer patients with a smoking history exhibited greater levels of D2R in lung endothelium. Our results suggest D2R agonists may represent a promising individualized therapy for lung cancer patients with high levels of endothelial D2R expression and a smoking history. PMID:25226814

  4. Inhibition of Receptor Signaling and of Glioblastoma-derived Tumor Growth by a Novel PDGFRβ Aptamer

    PubMed Central

    Camorani, Simona; Esposito, Carla L; Rienzo, Anna; Catuogno, Silvia; Iaboni, Margherita; Condorelli, Gerolama; de Franciscis, Vittorio; Cerchia, Laura

    2014-01-01

    Platelet-derived growth factor receptor β (PDGFRβ) is a cell-surface tyrosine kinase receptor implicated in several cellular processes including proliferation, migration, and angiogenesis. It represents a compelling therapeutic target in many human tumors, including glioma. A number of tyrosine kinase inhibitors under development as antitumor agents have been found to inhibit PDGFRβ. However, they are not selective as they present multiple tyrosine kinase targets. Here, we report a novel PDGFRβ-specific antagonist represented by a nuclease-resistant RNA-aptamer, named Gint4.T. This aptamer is able to specifically bind to the human PDGFRβ ectodomain (Kd: 9.6 nmol/l) causing a strong inhibition of ligand-dependent receptor activation and of downstream signaling in cell lines and primary cultures of human glioblastoma cells. Moreover, Gint4.T aptamer drastically inhibits cell migration and proliferation, induces differentiation, and blocks tumor growth in vivo. In addition, Gint4.T aptamer prevents PDGFRβ heterodimerization with and resultant transactivation of epidermal growth factor receptor. As a result, the combination of Gint4.T and an epidermal growth factor receptor–targeted aptamer is better at slowing tumor growth than either single aptamer alone. These findings reveal Gint4.T as a PDGFRβ-drug candidate with translational potential. PMID:24566984

  5. Pharmacological inhibition of KIT activates MET signaling in gastrointestinal stromal tumors

    PubMed Central

    Cohen, Noah A.; Zeng, Shan; Seifert, Adrian M.; Kim, Teresa S.; Sorenson, Eric C.; Greer, Jonathan B.; Beckman, Michael J.; Santamaria-Barria, Juan A.; Crawley, Megan H.; Green, Benjamin L.; Rossi, Ferdinand; Besmer, Peter; Antonescu, Cristina R.; DeMatteo, Ronald P.

    2015-01-01

    Gastrointestinal stromal tumors (GIST) are the most common adult sarcomas and the oncogenic driver is usually a KIT or PDGFRA mutation. While GIST are often initially sensitive to imatinib or other tyrosine kinase inhibitors, resistance generally develops necessitating backup strategies for therapy. In this study, we determined that a subset of human GIST specimens that acquired imatinib resistance acquired expression of activated forms of the MET oncogene. MET activation also developed after imatinib therapy in a mouse model of GIST (KitV558del/+ mice), where it was associated with increased tumor hypoxia. MET activation also occurred in imatinib-sensitive human GIST cell lines after imatinib treatment in vitro. MET inhibition by crizotinib or RNA interference was cytotoxic to an imatinib-resistant human GIST cell population. Moreover, combining crizotinib and imatinib was more effective than imatinib alone in imatinib-sensitive GIST models. Lastly, cabozantinib, a dual MET and KIT small molecule inhibitor, was markedly more effective than imatinib in multiple preclinical models of imatinib-sensitive and imatinib-resistant GIST. Collectively, our findings showed that activation of compensatory MET signaling by KIT inhibition may contribute to tumor resistance. Furthermore, our work offered a preclinical proof of concept for MET inhibition by cabozantinib as an effective strategy for GIST treatment. PMID:25836719

  6. A polypeptide from shark troponin I can inhibit angiogenesis and tumor growth.

    PubMed

    Xie, Qiuling; Yao, Sheng; Chen, Xiaojia; Xu, Lihui; Peng, Wendan; Zhang, Ling; Zhang, Qihao; Liang, Xu-Fang; Hong, An

    2012-02-01

    The shark troponin I gene (TnI) was found for the first time in this study to inhibit endothelial cell proliferation and angiogenesis. This shark TnI had 68.9% amino acid homology with human TnI, whereas the polypeptide from Lys91 to Leu123, which is thought to be the active site of TnI, had 78.8% homology with the corresponding fragment of human TnI. However, the polypeptide of shark had higher activity to inhibit the proliferation of HUVEC and tumor cell lines than that of human TnI. To investigate the anti-angiogenesis and anti-tumor effect of the shark TnI polypeptide, the DNA sequence of polypeptide (Lys91-Leu123) of white-spot catshark TnI(psTnI) was cloned and fused with the His-SUMO cDNA, followed by expression in Escherichia coli. After its purification by Ni(2+) affinity chromatography, the fusion His-SUMO-psTnI protein was digested with the SUMO enzyme to release psTnI. The inhibitory ability of this recombinant shark TnI polypeptide for angiogenesis was confirmed by chicken embryo allantoic membrane (CAM) test and IHC analysis. It was also found by breast carcinoma xenograft study in Balb/c mice that this polypeptide could inhibit tumor growth in vivo. PMID:21750912

  7. Tumoral expression of IL-33 inhibits tumor growth and modifies the tumor microenvironment through CD8+ T and NK cells.

    PubMed

    Gao, Xin; Wang, Xuefeng; Yang, Qianting; Zhao, Xin; Wen, Wen; Li, Gang; Lu, Junfeng; Qin, Wenxin; Qi, Yuan; Xie, Fang; Jiang, Jingting; Wu, Changping; Zhang, Xueguang; Chen, Xinchun; Turnquist, Heth; Zhu, Yibei; Lu, Binfeng

    2015-01-01

    Cancer immunotherapy has shown great promise as a new standard cancer therapeutic modality. However, the response rates are limited for current approach that depends on enhancing spontaneous antitumor immune responses. Therefore, increasing tumor immunogenicity by expressing appropriate cytokines should further improve the current immunotherapy. IL-33 is a member of the IL-1 family of cytokines and is released by necrotic epithelial cells or activated innate immune cells and is thus considered a "danger" signal. The role of IL-33 in promoting type 2 immune responses and tissue inflammation has been well established. However, whether IL-33 drives antitumor immune responses is controversial. Our previous work established that IL-33 promoted the function of CD8(+) T cells. In this study, we showed that the expression of IL-33 in two types of cancer cells potently inhibited tumor growth and metastasis. Mechanistically, IL-33 increased numbers and IFN-γ production by CD8(+) T and NK cells in tumor tissues, thereby inducing a tumor microenvironment favoring tumor eradication. Importantly, IL-33 greatly increased tumor Ag-specific CD8(+) T cells. Furthermore, both NK and CD8(+) T cells were required for the antitumor effect of IL-33. Moreover, depletion of regulatory T cells worked synergistically with IL-33 expression for tumor elimination. Our studies established "alarmin" IL-33 as a promising new cytokine for tumor immunotherapy through promoting cancer-eradicating type 1 immune responses. PMID:25429071

  8. Tumoral expression of IL-33 inhibits tumor growth and modifies the tumor microenvironment through CD8+ T and NK cells

    PubMed Central

    Gao, Xin; Wang, Xuefeng; Yang, Qianting; Zhao, Xin; Wen, Wen; Li, Gang; Lu, Junfeng; Qin, Wenxin; Qi, Yuan; Xie, Fang; Jiang, Jingting; Wu, Changping; Zhang, Xueguang; Chen, Xinchun; Turnquist, Heth; Zhu, Yibei; Lu, Binfeng

    2014-01-01

    Cancer immunotherapy has shown great promise as a new standard cancer therapeutic modality. However, the response rates are limited for current approach that depends on enhancing spontaneous antitumor immune responses. Therefore, increasing tumor immunogenicity by expressing appropriate cytokines should further improve the current immunotherapy. Interleukin-33 is a member of the IL-1 family of cytokines and is released by necrotic epithelial cells or activated innate immune cells and is thus considered a “danger” signal. The role of IL-33 in promoting type 2 immune responses and tissue inflammation has been well established. However, whether IL-33 drives antitumor immune responses is controversial. Our previous work established that IL-33 promoted the function of CD8+ T cells. Here, we showed that the expression of IL-33 in two types of cancer cells potently inhibited tumor growth and metastasis. Mechanistically, IL-33 increased numbers and IFNγ production by CD8+ T and NK cells in tumor tissues, thereby inducing a tumor microenvironment favoring tumor eradication. Importantly, IL-33 greatly increased tumor-antigen-specific CD8+ T cells. Furthermore, both NK and CD8+ T cells were required for the antitumor effect of IL-33. Moreover, depletion of regulatory T cells (Treg) worked synergistically with IL-33 expression for tumor elimination. Our studies established “alarmin” IL-33 as a promising new cytokine for tumor immunotherapy through promoting cancer-eradicating type 1 immune responses. PMID:25429071

  9. Photoactivation of lysosomally sequestered sunitinib after angiostatic treatment causes vascular occlusion and enhances tumor growth inhibition

    PubMed Central

    Nowak-Sliwinska, P; Weiss, A; van Beijnum, J R; Wong, T J; Kilarski, W W; Szewczyk, G; Verheul, H M W; Sarna, T; van den Bergh, H; Griffioen, A W

    2015-01-01

    The angiogenesis inhibitor sunitinib is a tyrosine kinase inhibitor that acts mainly on the VEGF and PDGF pathways. We have previously shown that sunitinib is sequestered in the lysosomes of exposed tumor and endothelial cells. This phenomenon is part of the drug-induced resistance observed in the clinic. Here, we demonstrate that when exposed to light, sequestered sunitinib causes immediate destruction of the lysosomes, resulting in the release of sunitinib and cell death. We hypothesized that this photoactivation of sunitinib could be used as a vaso-occlusive vascular-targeting approach to treating cancer. Spectral properties of sunitinib and its lysosomal accumulation were measured in vitro. The human A2780 ovarian carcinoma transplanted onto the chicken chorioallantoic membrane (CAM) and the Colo-26 colorectal carcinoma model in Balb/c mice were used to test the effects of administrating sunitinib and subsequently exposing tumor tissue to light. Tumors were subsequently resected and subject to immunohistochemical analysis. In A2780 ovarian carcinoma tumors, treatment with sunitinib+light resulted in immediate specific angio-occlusion, leading to a necrotic tumor mass 24 h after treatment. Tumor growth was inhibited by 70% as compared with the control group (**P<0.0001). Similar observations were made in the Colo-26 colorectal carcinoma, where light exposure of the sunitinib-treated mice inhibited tumor growth by 50% as compared with the control and by 25% as compared with sunitinib-only-treated tumors (N≥4; P=0.0002). Histology revealed that photoactivation of sunitinib resulted in a change in tumor vessel architecture. The current results suggest that the spectral properties of sunitinib can be exploited for application against certain cancer indications. PMID:25675301

  10. PTEN inhibits PREX2-catalyzed activation of RAC1 to restrain tumor cell invasion

    PubMed Central

    Mense, Sarah M.; Barrows, Douglas; Hodakoski, Cindy; Steinbach, Nicole; Schoenfeld, David; Su, William; Hopkins, Benjamin D.; Su, Tao; Fine, Barry; Hibshoosh, Hanina; Parsons, Ramon

    2016-01-01

    The tumor suppressor PTEN restrains cell migration and invasion by a mechanism that is independent of inhibition of the PI3K pathway and decreased activation of the kinase AKT. PREX2, a widely distributed GEF that activates the GTPase RAC1, binds to and inhibits PTEN. We used mouse embryonic fibroblasts and breast cancer cell lines to show that PTEN suppresses cell migration and invasion by blocking PREX2 activity. In addition to metabolizing the phosphoinositide PIP3, PTEN inhibited PREX2-induced invasion by a mechanism that required the tail domain of PTEN, but not its lipid phosphatase activity. Fluorescent nucleotide exchange assays revealed that PTEN inhibited the GEF activity of PREX2 toward RAC1. PREX2 is a frequently mutated GEF in cancer, and examination of human tumor data showed that PREX2 mutation was associated with high PTEN expression. Therefore, we tested whether cancer-derived somatic PREX2 mutants, which accelerate tumor formation of immortalized melanocytes, were inhibited by PTEN. The three stably expressed, somatic PREX2 cancer mutants that we tested were resistant to PTEN-mediated inhibition of invasion but retained the ability to inhibit the lipid phosphatase activity of PTEN. In vitro analysis showed that PTEN did not block the GEF activity of two PREX2 cancer mutants and had a reduced binding affinity for the third. Thus, PTEN antagonized migration and invasion by restraining PREX2 GEF activity, and PREX2 mutants are likely selected in cancer to escape PTEN-mediated inhibition of invasion. PMID:25829446

  11. Wee1 inhibition potentiates Wip1-dependent p53-negative tumor cell death during chemotherapy

    PubMed Central

    Clausse, V; Goloudina, A R; Uyanik, B; Kochetkova, E Y; Richaud, S; Fedorova, O A; Hammann, A; Bardou, M; Barlev, N A; Garrido, C; Demidov, O N

    2016-01-01

    Inactivation of p53 found in more than half of human cancers is often associated with increased tumor resistance to anti-cancer therapy. We have previously shown that overexpression of the phosphatase Wip1 in p53-negative tumors sensitizes them to chemotherapeutic agents, while protecting normal tissues from the side effects of anti-cancer treatment. In this study, we decided to search for kinases that prevent Wip1-mediated sensitization of cancer cells, thereby interfering with efficacy of genotoxic anti-cancer drugs. To this end, we performed a flow cytometry-based screening in order to identify kinases that regulated the levels of γH2AX, which were used as readout. Another criterion of the screen was increased sensitivity of p53-negative tumor cells to cisplatin (CDDP) in a Wip1-dependent manner. We have found that a treatment with a low dose (75 nM) of MK-1775, a recently described specific chemical inhibitor of Wee1, decreases CDDP-induced H2AX phosphorylation in p53-negative cells and enhances the Wip1-sensitization of p53-negative tumors. We were able to reduce CDDP effective concentration by 40% with a combination of Wip1 overexpression and Wee1 kinase inhibition. We have observed that Wee1 inhibition potentiates Wip1-dependent tumor sensitization effect by reducing levels of Hipk2 kinase, a negative regulator of Wip1 pathway. In addition, during CDDP treatment, the combination of Wee1 inhibition and Wip1 overexpression has a mild but significant protective effect in normal cells and tissues. Our results indicate that inhibition of the negative regulators of Wip1 pathway, Wee1 and Hipk2, in p53-negative tumors could potentiate efficiency of chemotherapeutic agents without concomitant increase of cytotoxicity in normal tissues. The development and clinical use of Wee1 and Hipk1 kinase chemical inhibitors might be a promising strategy to improve anti-cancer therapy. PMID:27077811

  12. Wee1 inhibition potentiates Wip1-dependent p53-negative tumor cell death during chemotherapy.

    PubMed

    Clausse, V; Goloudina, A R; Uyanik, B; Kochetkova, E Y; Richaud, S; Fedorova, O A; Hammann, A; Bardou, M; Barlev, N A; Garrido, C; Demidov, O N

    2016-01-01

    Inactivation of p53 found in more than half of human cancers is often associated with increased tumor resistance to anti-cancer therapy. We have previously shown that overexpression of the phosphatase Wip1 in p53-negative tumors sensitizes them to chemotherapeutic agents, while protecting normal tissues from the side effects of anti-cancer treatment. In this study, we decided to search for kinases that prevent Wip1-mediated sensitization of cancer cells, thereby interfering with efficacy of genotoxic anti-cancer drugs. To this end, we performed a flow cytometry-based screening in order to identify kinases that regulated the levels of γH2AX, which were used as readout. Another criterion of the screen was increased sensitivity of p53-negative tumor cells to cisplatin (CDDP) in a Wip1-dependent manner. We have found that a treatment with a low dose (75 nM) of MK-1775, a recently described specific chemical inhibitor of Wee1, decreases CDDP-induced H2AX phosphorylation in p53-negative cells and enhances the Wip1-sensitization of p53-negative tumors. We were able to reduce CDDP effective concentration by 40% with a combination of Wip1 overexpression and Wee1 kinase inhibition. We have observed that Wee1 inhibition potentiates Wip1-dependent tumor sensitization effect by reducing levels of Hipk2 kinase, a negative regulator of Wip1 pathway. In addition, during CDDP treatment, the combination of Wee1 inhibition and Wip1 overexpression has a mild but significant protective effect in normal cells and tissues. Our results indicate that inhibition of the negative regulators of Wip1 pathway, Wee1 and Hipk2, in p53-negative tumors could potentiate efficiency of chemotherapeutic agents without concomitant increase of cytotoxicity in normal tissues. The development and clinical use of Wee1 and Hipk1 kinase chemical inhibitors might be a promising strategy to improve anti-cancer therapy. PMID:27077811

  13. Potentiation of platinum antitumor effects in human lung tumor xenografts by the angiogenesis inhibitor squalamine: effects on tumor neovascularization.

    PubMed

    Schiller, J H; Bittner, G

    1999-12-01

    Squalamine is a novel anti-angiogenic aminosterol that is postulated to inhibit neovascularization by selectively inhibiting the sodium-hydrogen antiporter exchanger. To determine how to most effectively use this agent in patients with cancer, we examined the antitumor effects of squalamine with or without cytotoxic agents in human lung cancer xenografts and correlated these observations with the degree of tumor neovascularization. No direct cytotoxic effects of squalamine against tumor cells were observed in vitro with or without cisplatin. Squalamine was effective in inhibiting the establishment of H460 human tumors in BALBc nude mice but was ineffective in inhibiting the growth of H460, CALU-6, or NL20T-A human tumor xenografts when administered i.p. to mice bearing established tumors. However, when combined with cisplatin or carboplatin, squalamine increased tumor growth delay by > or =1.5-fold in the three human lung carcinoma cell lines compared with cisplatin or carboplatin alone. No enhancement of antitumor activity was observed when squalamine was combined with paclitaxel, vinorelbine, gemcitabine, or docetaxel. Repeated cycles of squalamine plus cisplatin administration delayed H460 tumor growth >8.6-fold. Squalamine plus cisplatin reduced CD31 vessel formation by 25% compared with controls, squalamine alone, or cisplatin alone; however, no inhibition in CD31 vessel formation was observed when squalamine was combined with vinorelbine. These data demonstrate that the combination of squalamine and a platinum analog has significant preclinical antitumor activity against human lung cancer that is related to the anti-angiogenic effects of squalamine. PMID:10632372

  14. Resveratrol-loaded nanocapsules inhibit murine melanoma tumor growth.

    PubMed

    Carletto, Bruna; Berton, Juliana; Ferreira, Tamara Nascimento; Dalmolin, Luciana Facco; Paludo, Katia Sabrina; Mainardes, Rubiana Mara; Farago, Paulo Vitor; Favero, Giovani Marino

    2016-08-01

    In this study, resveratrol-loaded nanocapsules were developed and its antitumor activity tested on a melanoma mice model. These nanocapsules were spherically-shaped and presented suitable size, negative charge and high encapsulation efficiency for their use as a modified-release system of resveratrol. Nanoencapsulation leads to the drug amorphization. Resveratrol-loaded nanoparticles reduced cell viability of murine melanoma cells. There was a decrease in tumor volume, an increase in the necrotic area and inflammatory infiltrate of melanoma when resveratrol-loaded nanocapsules were compared to free resveratrol in treated mice. Nanoencapsulation of resveratrol also prevented metastasis and pulmonary hemorrhage. This modified-release technology containing resveratrol can be used as a feasible approach in order to inhibit murine melanoma tumor growth. PMID:27070053

  15. Inhibition of tumor growth and metastasis by photoimmunotherapy targeting tumor-associated macrophage in a sorafenib-resistant tumor model.

    PubMed

    Zhang, Chenran; Gao, Liquan; Cai, Yuehong; Liu, Hao; Gao, Duo; Lai, Jianhao; Jia, Bing; Wang, Fan; Liu, Zhaofei

    2016-04-01

    Tumor-associated macrophages (TAMs) play essential roles in tumor invasion and metastasis, and contribute to drug resistance. Clinical evidence suggests that TAM levels are correlated with local tumor relapse, distant metastasis, and poor prognosis in patients. In this study, we synthesized a TAM-targeted probe (IRD-αCD206) by conjugating a monoclonal anti-CD206 antibody with a near-infrared phthalocyanine dye. We then investigated the potential application of the IRD-αCD206 probe to near-infrared fluorescence (NIRF) imaging and photoimmunotherapy (PIT) of tumors resistant to treatment with the kinase inhibitor sorafenib. Sorafenib treatment had no effect on tumor growth in a 4T1 mouse model of breast cancer, but induced M2 macrophage polarization in tumors. M2 macrophage recruitment by sorafenib-treated 4T1 tumors was noninvasively visualized by in vivo NIRF imaging of IRD-αCD206. Small-animal single-photon emission computed tomography (SPECT)/CT and intratumoral microdistribution analysis indicated TAM-specific localization of the IRD-αCD206 probe in 4T1 tumors after several rounds of sorafenib treatment. Upon light irradiation, IRD-αCD206 suppressed the growth of sorafenib-resistant tumors. In vivo CT imaging and ex vivo histological analysis confirmed the inhibition of lung metastasis in mice by IRD-αCD206 PIT. These results demonstrate the utility of the IRD-αCD206 probe for TAM-targeted diagnostic imaging and treatment of tumors that are resistant to conventional therapeutics. PMID:26803407

  16. Mo polyoxometalate nanoparticles inhibit tumor growth and vascular endothelial growth factor induced angiogenesis

    NASA Astrophysics Data System (ADS)

    Zheng, Wenjing; Yang, Licong; Liu, Ying; Qin, Xiuying; Zhou, Yanhui; Zhou, Yunshan; Liu, Jie

    2014-06-01

    Tumor growth depends on angiogenesis, which can furnish the oxygen and nutrients that proliferate tumor cells. Thus, blocking angiogenesis can be an effective strategy to inhibit tumor growth. In this work, three typical nanoparticles based on polyoxometalates (POMs) have been prepared; we investigated their capability as antitumor and anti-angiogenesis agents. We found that Mo POM nanoparticles, especially complex 3, inhibited the growth of human hepatocellular liver carcinoma cells (HepG2) through cellular reactive oxygen species levels’ elevation and mitochondrial membrane potential damage. Complex 3 also suppressed the proliferation, migration, and tube formation of endothelial cells in vitro and chicken chorioallantoic membrane development ex vivo. Furthermore, western blot analysis of cell signaling molecules indicated that Mo POMs blocked the vascular endothelial growth factor receptor 2-mediated ERK1/2 and AKT signaling pathways in endothelial cells. Using transmission electron microscopy, we demonstrated their cellular uptake and localization within the cytoplasm of HepG2 cells. These results indicate that, owing to the extraordinary physical and chemical properties, Mo POM nanoparticles can significantly inhibit tumor growth and angiogenesis, which makes them potential drug candidates in anticancer and anti-angiogenesis therapies.

  17. MIF Maintains the Tumorigenic Capacity of Brain Tumor-Initiating Cells by Directly Inhibiting p53.

    PubMed

    Fukaya, Raita; Ohta, Shigeki; Yaguchi, Tomonori; Matsuzaki, Yumi; Sugihara, Eiji; Okano, Hideyuki; Saya, Hideyuki; Kawakami, Yutaka; Kawase, Takeshi; Yoshida, Kazunari; Toda, Masahiro

    2016-05-01

    Tumor-initiating cells thought to drive brain cancer are embedded in a complex heterogeneous histology. In this study, we isolated primary cells from 21 human brain tumor specimens to establish cell lines with high tumorigenic potential and to identify the molecules enabling this capability. The morphology, sphere-forming ability upon expansion, and differentiation potential of all cell lines were indistinguishable in vitro However, testing for tumorigenicity revealed two distinct cell types, brain tumor-initiating cells (BTIC) and non-BTIC. We found that macrophage migration inhibitory factor (MIF) was highly expressed in BTIC compared with non-BTIC. MIF bound directly to both wild-type and mutant p53 but regulated p53-dependent cell growth by different mechanisms, depending on glioma cell line and p53 status. MIF physically interacted with wild-type p53 in the nucleus and inhibited its transcription-dependent functions. In contrast, MIF bound to mutant p53 in the cytoplasm and abrogated transcription-independent induction of apoptosis. Furthermore, MIF knockdown inhibited BTIC-induced tumor formation in a mouse xenograft model, leading to increased overall survival. Collectively, our findings suggest that MIF regulates BTIC function through direct, intracellular inhibition of p53, shedding light on the molecular mechanisms underlying the tumorigenicity of certain malignant brain cells. Cancer Res; 76(9); 2813-23. ©2016 AACR. PMID:26980763

  18. Antibody against CD44s Inhibits Pancreatic Tumor Initiation and Post-Radiation Recurrence in Mice

    PubMed Central

    Li, Ling; Hao, Xinbao; Qin, Jun; Tang, Wenhua; He, Fengtian; Smith, Amber; Zhang, Min; Simeone, Diane M.; Qiao, Xiaotan T.; Chen, Zhi-Nan; Lawrence, Theodore S.; Xu, Liang

    2014-01-01

    Background & Aims CD44s is a surface marker of tumor-initiating cells (TICs); high tumor levels correlate with metastasis and recurrence, as well as poor outcomes of patients. Monoclonal antibodies against CD44s might eliminate TICs with minimal toxicity. This strategy is unclear for treatment of pancreatic cancer, and little is known about how anti-CD44s affect pancreatic cancer initiation or recurrence after radiotherapy. Methods 192 pairs of human pancreatic adenocarcinoma and adjacent non-tumor pancreatic tissues were collected from patients undergoing surgery. We measured CD44s levels in tissue samples and pancreatic cancer cell lines by immunohistochemistry, real-time PCR and immunoblot; levels were correlated with patient survival times. We studied the effects of anti-CD44s in mice with human pancreatic tumor xenografts, and used flow cytometry to determine effects on TICs. Changes in CD44s signaling were examined by real-time PCR, immunoblot, reporter assay, and in vitro tumorsphere formation assays. Results Levels of CD44s were significantly higher in pancreatic cancer than adjacent non-tumor tissues. Patients whose tumors expressed high levels of CD44s had a median survival of 10 months, compared to 43 months for those with low levels. Anti-CD44s reduced growth, metastasis, and post-radiation recurrence of pancreatic xenograft tumors in mice. The antibody reduced the number of TICs in cultured pancreatic cancer cells and in xenograft tumors, as well as their tumorigenicity. In cultured pancreatic cancer cell lines, anti-CD44s downregulated the stem cell self-renewal genes Nanog, Sox-2, and Rex-1 and inhibited STAT3-mediated cell proliferation and survival signaling. Conclusions The TIC marker CD44s is upregulated in human pancreatic tumors and associated with patient survival time. CD44s is required for initiation, growth, metastasis, and post-radiation recurrence of xenograft tumors in mice. Anti-CD44s eliminated bulk tumor cells as well as TICs from the

  19. Oridonin inhibits tumor growth in glioma by inducing cell cycle arrest and apoptosis.

    PubMed

    Zhang, X-H; Liu, Y-X; Jia, M; Han, J-S; Zhao, M; Ji, S-P; Li, A-M

    2014-01-01

    Glioma is the most common malignant intracranial tumors. Despite newly developed therapies, these treatments mainly target oncogenic signals, and unfortunately, fail to provide enough survival benefit in both human patients and mouse xenograft models, especially the first-generation therapies. Oridonin is purified from the Chinese herb Rabdosia rubescens and considered to exert extensive anti-cancer effects on human tumorigenesis. In this study, we systemically investigated the role of Oridonin in tumor growth and the underlying mechanisms in human glioma. We found that Oridonin inhibited cell proliferations in a dose- and time-dependent manner in both glioma U87 and U251 cells. Moreover, these anti-cancer effects were also confirmed in a mouse model bearing glioma. Furthermore, cell cycle arrest in S phase was observed in Oridonin-mediated growth inhibition by flow cytometry. Cell cycle arrest in S phase led to eventual cell apoptosis, as revealed by Hoechst 33342 staining and annexin V/PI double-staining. The cell apoptosis might be accomplished through a mitochondrial manner. In all, we were the first to our knowledge to report that Oridonin could exert anti-cancer effects on tumor growth in human glioma by inducing cell cycle arrest and eventual cell apoptosis. The identification of Oridonin as a critical mediator of glioma growth may potentiate Oridonin as a novel therapeutic strategies in glioma treatments. PMID:25553351

  20. Methylthioadenosine (MTA) inhibits melanoma cell proliferation and in vivo tumor growth

    PubMed Central

    2010-01-01

    Background Melanoma is the most deadly form of skin cancer without effective treatment. Methylthioadenosine (MTA) is a naturally occurring nucleoside with differential effects on normal and transformed cells. MTA has been widely demonstrated to promote anti-proliferative and pro-apoptotic responses in different cell types. In this study we have assessed the therapeutic potential of MTA in melanoma treatment. Methods To investigate the therapeutic potential of MTA we performed in vitro proliferation and viability assays using six different mouse and human melanoma cell lines wild type for RAS and BRAF or harboring different mutations in RAS pathway. We also have tested its therapeutic capabilities in vivo in a xenograft mouse melanoma model and using variety of molecular techniques and tissue culture we investigated its anti-proliferative and pro-apoptotic properties. Results In vitro experiments showed that MTA treatment inhibited melanoma cell proliferation and viability in a dose dependent manner, where BRAF mutant melanoma cell lines appear to be more sensitive. Importantly, MTA was effective inhibiting in vivo tumor growth. The molecular analysis of tumor samples and in vitro experiments indicated that MTA induces cytostatic rather than pro-apoptotic effects inhibiting the phosphorylation of Akt and S6 ribosomal protein and inducing the down-regulation of cyclin D1. Conclusions MTA inhibits melanoma cell proliferation and in vivo tumor growth particularly in BRAF mutant melanoma cells. These data reveal a naturally occurring drug potentially useful for melanoma treatment. PMID:20529342

  1. Inhibition of protein kinase CK2 reduces CYP24A1 expression and enhances 1,25-dihydroxyvitamin D3 anti-tumor activity in human prostate cancer cells

    PubMed Central

    Luo, Wei; Yu, Wei-Dong; Ma, Yingyu; Chernov, Mikhail; Trump, Donald L.; Johnson, Candace S.

    2013-01-01

    Vitamin D has broad range of physiological functions and anti-tumor effects. 24-hydroxylase, encoded by the CYP24A1 gene, is the key enzyme for degrading many forms of vitamin D including the most active form, 1,25D3. Inhibition of CYP24A1 enhances 1,25D3 anti-tumor activity. In order to isolate regulators of CYP24A1 expression in prostate cancer cells, we established a stable prostate cancer cell line PC3 with CYP24A1 promoter driving luciferase expression to screen a small molecular library for compounds that inhibit CYP24A1 promoter activity. From this screening, we identified, 4,5,6,7-tetrabromobenzimidazole (TBBz), a protein kinase CK2 selective inhibitor as a disruptor of CYP24A1 promoter activity. We show that TBBz inhibits CYP24A1 promoter activity induced by 1,25D3 in prostate cancer cells. In addition, TBBz downregulates endogenous CYP24A1 mRNA level in TBBz treated PC3 cells. Furthermore, siRNA-mediated CK2 knockdown reduces 1,25D3 induced CYP24A1 mRNA expression in PC3 cells. These results suggest that CK2 contributes to 1,25D3 mediated target gene expression. Lastly, inhibition of CK2 by TBBz or CK2 siRNA significantly enhanced 1,25D3 mediated anti-proliferative effect in vitro and in vivo in a xenograft model. In summary, our findings reveal that protein kinase CK2 is involved in the regulation of CYP24A1 expression by 1,25D3 and CK2 inhibitor enhances 1,25D3 mediated anti-tumor effect. PMID:23358686

  2. Oridonin Inhibits Tumor Growth and Metastasis through Anti-Angiogenesis by Blocking the Notch Signaling

    PubMed Central

    Li, Jingjie; Deng, Huayun; Song, Yajuan; Zhai, Dong; Peng, Yi; Lu, Xiaoling; Liu, Mingyao; Zhao, Yongxiang; Yi, Zhengfang

    2014-01-01

    While significant progress has been made in understanding the anti-inflammatory and anti-proliferative effects of the natural diterpenoid component Oridonin on tumor cells, little is known about its effect on tumor angiogenesis or metastasis and on the underlying molecular mechanisms. In this study, Oridonin significantly suppressed human umbilical vascular endothelial cells (HUVECs) proliferation, migration, and apillary-like structure formation in vitro. Using aortic ring assay and mouse corneal angiogenesis model, we found that Oridonin inhibited angiogenesis ex vivo and in vivo. In our animal experiments, Oridonin impeded tumor growth and metastasis. Immunohistochemistry analysis further revealed that the expression of CD31 and vWF protein in xenografts was remarkably decreased by the Oridonin. Furthermore, Oridonin reinforced endothelial cell-cell junction and impaired breast cancer cell transendothelial migration. Mechanistically, Oridonin not only down-regulated Jagged2 expression and Notch1 activity but also decreased the expression of their target genes. In conclusion, our results demonstrated an original role of Oridonin in inhibiting tumor angiogenesis and propose a mechanism. This study also provides new evidence supporting the central role of Notch in tumor angiogenesis and suggests that Oridonin could be a potential drug candidate for angiogenesis related diseases. PMID:25485753

  3. Allosteric antibody inhibition of human hepsin protease.

    PubMed

    Koschubs, Tobias; Dengl, Stefan; Dürr, Harald; Kaluza, Klaus; Georges, Guy; Hartl, Christiane; Jennewein, Stefan; Lanzendörfer, Martin; Auer, Johannes; Stern, Alvin; Huang, Kuo-Sen; Packman, Kathryn; Gubler, Ueli; Kostrewa, Dirk; Ries, Stefan; Hansen, Silke; Kohnert, Ulrich; Cramer, Patrick; Mundigl, Olaf

    2012-03-15

    Hepsin is a type II transmembrane serine protease that is expressed in several human tissues. Overexpression of hepsin has been found to correlate with tumour progression and metastasis, which is so far best studied for prostate cancer, where more than 90% of such tumours show this characteristic. To enable improved future patient treatment, we have developed a monoclonal humanized antibody that selectively inhibits human hepsin and does not inhibit other related proteases. We found that our antibody, hH35, potently inhibits hepsin enzymatic activity at nanomolar concentrations. Kinetic characterization revealed non-linear, slow, tight-binding inhibition. This correlates with the crystal structure we obtained for the human hepsin-hH35 antibody Fab fragment complex, which showed that the antibody binds hepsin around α3-helix, located far from the active centre. The unique allosteric mode of inhibition of hH35 is distinct from the recently described HGFA (hepatocyte growth factor activator) allosteric antibody inhibition. We further explain how a small change in the antibody design induces dramatic structural rearrangements in the hepsin antigen upon binding, leading to complete enzyme inactivation. PMID:22132769

  4. Targeting BRCA1 localization to augment breast tumor sensitivity to poly(ADP-ribose) polymerase inhibition

    PubMed Central

    Yang, Eddy S.; Nowsheen, Somaira; Rahman, Mohammad A.; Cook, Rebecca S.; Xia, Fen

    2013-01-01

    Poly(ADP-ribose) polymerase inhibitors have gained recent attention due to their highly selective killing of BRCA1/2 mutated and DNA double strand break (DSB) repair deficient tumors. Unfortunately, the majority of sporadic breast cancers carry wild-type BRCA1/2 and are proficient in DSB repair. We and others have shown that BRCA1 is a nuclear/cytoplasm shuttling protein which is transiently exported from the nucleus to the cytosol upon various stimuli. Thus, we hypothesized that depletion of nuclear BRCA1 would compromise DSB repair and subsequently render sporadic tumors susceptible to PARP inhibition. Indeed, in human sporadic breast cancer cells with functional BRCA1 and proficient DSB repair, a transient nuclear depletion of BRCA1 and subsequent HR repair deficit was induced with either truncated BRCA1 or irradiation. This rendered these human sporadic breast cancer cells susceptible to PARP inhibition. These observations were confirmed genetically using mislocated BRCA1 mutants as well as in vivo in mice bearing breast tumor xenografts. These data support the potential strategy of targeting BRCA1 location to convert BRCA1-proficient sporadic tumors to be susceptible to the synthetic lethal combination with PARP inhibitors. PMID:22962264

  5. HDAC6 inhibition restores ciliary expression and decreases tumor growth

    PubMed Central

    Gradilone, Sergio A; Radtke, Brynn N; Bogert, Pamela S; Huang, Bing Q; Gajdos, Gabriella B; LaRusso, Nicholas F

    2013-01-01

    Primary cilia are multisensory organelles recently found to be absent in some tumor cells, but the mechanisms of deciliation and the role of cilia in tumor biology remain unclear. Cholangiocytes, the epithelial cells lining the biliary tree, normally express primary cilia and their interaction with bile components regulates multiple processes, including proliferation and transport. Utilizing cholangiocarcinoma (CCA) as a model, we found primary cilia are reduced in CCA by a mechanism involving histone deacetylase 6 (HDAC6). The experimental deciliation of normal cholangiocyte cells increased the proliferation rate and induced anchorage-independent growth. Furthermore, deciliation induced the activation of MAPK and Hedgehog signaling, two important pathways involved in CCA development. We found HDAC6 is overexpressed in CCA and overexpression of HDAC6 in normal cholangiocytes induced deciliation, and increased both proliferation and anchorage-independent growth. To evaluate the effect of cilia restoration on tumor cells, we targeted HDAC6 by shRNA or by the pharmacologic inhibitor, tubastatin-A. Both approaches restored the expression of primary cilia in CCA cell lines and decreased cell proliferation and anchorage-independent growth. The effects of tubastatin-A were abolished when CCA cells were rendered unable to regenerate cilia by stable transfection of IFT88-shRNA. Finally, inhibition of HDAC6 by tubastatin-A also induced a significant decrease in tumor growth in a CCA animal model. Our data support a key role for primary cilia in malignant transformation, provide a plausible mechanism for their involvement, and suggest that restoration of primary cilia in tumor cells by HDAC6 targeting may be a potential therapeutic approach for CCA. PMID:23370327

  6. MRI and MRS of human brain tumors.

    PubMed

    Hou, Bob L; Hu, Jiani

    2009-01-01

    The purpose of this chapter is to provide an introduction to magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) of human brain tumors, including the primary applications and basic terminology involved. Readers who wish to know more about this broad subject should seek out the referenced books (1. Tofts (2003) Quantitative MRI of the brain. Measuring changes caused by disease. Wiley; Bradley and Stark (1999) 2. Magnetic resonance imaging, 3rd Edition. Mosby Inc; Brown and Semelka (2003) 3. MRI basic principles and applications, 3rd Edition. Wiley-Liss) or reviews (4. Top Magn Reson Imaging 17:127-36, 2006; 5. JMRI 24:709-724, 2006; 6. Am J Neuroradiol 27:1404-1411, 2006).MRI is the most popular means of diagnosing human brain tumors. The inherent difference in the magnetic resonance (MR) properties of water between normal tissues and tumors results in contrast differences on the image that provide the basis for distinguishing tumors from normal tissues. In contrast to MRI, which provides spatial maps or images using water signals of the tissues, proton MRS detects signals of tissue metabolites. MRS can complement MRI because the observed MRS peaks can be linked to inherent differences in biochemical profiles between normal tissues and tumors.The goal of MRI and MRS is to characterize brain tumors, including tumor core, edge, edema, volume, types, and grade. The commonly used brain tumor MRI protocol includes T2-weighted images and T1-weighted images taken both before and after the injection of a contrast agent (typically gadolinium: Gd). The commonly used MRS technique is either point-resolved spectroscopy (PRESS) or stimulated echo acquisition mode (STEAM). PMID:19381963

  7. Müllerian inhibiting substance/anti-Müllerian hormone: A novel treatment for gynecologic tumors

    PubMed Central

    Kim, Jang Heub; MacLaughlin, David T.

    2014-01-01

    Müllerian inhibiting substance (MIS), also called anti-Müllerian hormone (AMH), is a member of the transforming growth factor-β super-family of growth and differentiation response modifiers. It is produced in immature Sertoli cells in male embryos and binds to MIS/AMH receptors in primordial Müllerian ducts to cause regression of female reproductive structures that are the precursors to the fallopian tubes, the surface epithelium of the ovaries, the uterus, the cervix, and the upper third of the vagina. Because most gynecologic tumors originate from Müllerian duct-derived tissues, and since MIS/AMH causes regression of the Müllerian duct in male embryos, it is expected to inhibit the growth of gynecologic tumors. Purified recombinant human MIS/AMH causes growth inhibition of epithelial ovarian cancer cells and cell lines in vitro and in vitro via MIS receptor-mediated mechanism. Furthermore, several lines of evidence suggest that MIS/AMH inhibits proliferation in tissues and cell lines of other MIS/AMH receptor-expressing gynecologic tumors such as cervical, endometrial, breast, and in endometriosis as well. These findings indicate that bioactive MIS/AMH recombinant protein should be tested in patients against tumors expressing the MIS/AMH receptor complex, perhaps beginning with ovarian cancer because it has the worst prognosis. The molecular tools to identify MIS/AMH receptor expressing ovarian and other cancers are in place, thus, it is possible to select patients for treatment. An MIS/AMH ELISA exists to follow administered doses of MIS/AMH, as well. Clinical trials await the production of sufficient supplies of qualified recombinant human MIS/AMH for this purpose. PMID:25264524

  8. Glipizide, an antidiabetic drug, suppresses tumor growth and metastasis by inhibiting angiogenesis.

    PubMed

    Qi, Cuiling; Zhou, Qin; Li, Bin; Yang, Yang; Cao, Liu; Ye, Yuxiang; Li, Jiangchao; Ding, Yi; Wang, Huiping; Wang, Jintao; He, Xiaodong; Zhang, Qianqian; Lan, Tian; Lee, Kenneth Ka Ho; Li, Weidong; Song, Xiaoyu; Zhou, Jia; Yang, Xuesong; Wang, Lijing

    2014-10-30

    Angiogenesis is involved in the development, progression and metastasis of various human cancers. Herein, we report the discovery of glipizide, a widely used drug for type 2 diabetes mellitus, as a promising anticancer agent through the inhibition of tumor angiogenesis. By high-throughput screening (HTS) of an FDA approved drug library utilizing our in vivo chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) models, glipizide has been identified to significantly inhibit blood vessel formation and development. Moreover, glipizide was found to suppress tumor angiogenesis, tumor growth and metastasis using xenograft tumor and MMTV-PyMT transgenic mouse models. We further revealed that the anticancer capability of glipizide is not attributed to its antiproliferative effects, which are not significant against various human cancer cell lines. To investigate whether its anticancer efficacy is associated with the glucose level alteration induced by glipizide application, glimepiride, another medium to long-acting sulfonylurea antidiabetic drug in the same class, was employed for the comparison studies in the same fashion. Interestingly, glimepiride has demonstrated no significant impact on the tumor growth and metastasis, indicating that the anticancer effects of glipizide is not ascribed to its antidiabetic properties. Furthermore, glipizide suppresses endothelial cell migration and the formation of tubular structures, thereby inhibiting angiogenesis by up-regulating the expression of natriuretic peptide receptor A. These findings uncover a novel mechanism of glipizide as a potential cancer therapy, and also for the first time, provide direct evidence to support that treatment with glipizide may reduce the cancer risk for diabetic patients. PMID:25294818

  9. A Novel Potent Oral Series of VEGFR2 Inhibitors Abrogate Tumor Growth by Inhibiting Angiogenesis.

    PubMed

    Bold, Guido; Schnell, Christian; Furet, Pascal; McSheehy, Paul; Brüggen, Josef; Mestan, Jürgen; Manley, Paul W; Drückes, Peter; Burglin, Marion; Dürler, Ursula; Loretan, Jacqueline; Reuter, Robert; Wartmann, Markus; Theuer, Andreas; Bauer-Probst, Beatrice; Martiny-Baron, Georg; Allegrini, Peter; Goepfert, Arnaud; Wood, Jeanette; Littlewood-Evans, Amanda

    2016-01-14

    This paper describes the identification of 6-(pyrimidin-4-yloxy)-naphthalene-1-carboxamides as a new class of potent and selective human vascular endothelial growth factor receptor 2 (VEGFR2) tyrosine kinase inhibitors. In biochemical and cellular assays, the compounds exhibit single-digit nanomolar potency toward VEGFR2. Compounds of this series show good exposure in rodents when dosed orally. They potently inhibit VEGF-driven angiogenesis in a chamber model and rodent tumor models at daily doses of less than 3 mg/kg by targeting the tumor vasculature as demonstrated by ELISA for TIE-2 in lysates or by immunohistochemical analysis. This novel series of compounds shows a potential for the treatment of solid tumors and other diseases where angiogenesis plays an important role. PMID:26629594

  10. Anticancer activity of MPT0G157, a derivative of indolylbenzenesulfonamide, inhibits tumor growth and angiogenesis.

    PubMed

    Huang, Yen-Chia; Huang, Fang-I; Mehndiratta, Samir; Lai, Ssu-Chia; Liou, Jing-Ping; Yang, Chia-Ron

    2015-07-30

    Histone deacetylases (HDACs) display multifaceted functions by coordinating the interaction of signal pathways with chromatin structure remodeling and the activation of non-histone proteins; these epigenetic regulations play an important role during malignancy progression. HDAC inhibition shows promise as a new strategy for cancer therapy; three HDAC inhibitors have been approved. We previously reported that N-hydroxy-3-{4-[2-(2-methyl-1H-indol-3-yl)-ethylsulfamoyl]-phenyl}-acrylamide (MPT0G157), a novel indole-3-ethylsulfamoylphenylacrylamide compound, demonstrated potent HDAC inhibition and anti-inflammatory effects. In this study, we evaluated its anti-cancer activity in vitro and in vivo. MPT0G157 treatment significantly inhibited different tumor growth at submicromolar concentration and was particularly potent in human colorectal cancer (HCT116) cells. Apoptosis and inhibited HDACs activity induced by MPT0G157 was more potent than that by the marketed drugs PXD101 (Belinostat) and SAHA (Vorinostat). In an in vivo model, MPT0G157 markedly inhibited HCT116 xenograft tumor volume and reduced matrigel-induced angiogenesis. The anti-angiogenetic effect of MPT0G157 was found to increase the hyperacetylation of heat shock protein 90 (Hsp90) and promote hypoxia-inducible factor-1α (HIF-1α) degradation followed by down-regulation of vascular endothelial growth factor (VEGF) expression. Our results demonstrate that MPT0G157 has potential as a new drug candidate for cancer therapy. PMID:26087180

  11. Anticancer activity of MPT0G157, a derivative of indolylbenzenesulfonamide, inhibits tumor growth and angiogenesis

    PubMed Central

    Mehndiratta, Samir; Lai, Ssu-Chia; Liou, Jing-Ping; Yang, Chia-Ron

    2015-01-01

    Histone deacetylases (HDACs) display multifaceted functions by coordinating the interaction of signal pathways with chromatin structure remodeling and the activation of non-histone proteins; these epigenetic regulations play an important role during malignancy progression. HDAC inhibition shows promise as a new strategy for cancer therapy; three HDAC inhibitors have been approved. We previously reported that N-hydroxy-3-{4-[2-(2-methyl-1H-indol-3-yl)-ethylsulfamoyl]-phenyl}-acrylamide (MPT0G157), a novel indole-3-ethylsulfamoylphenylacrylamide compound, demonstrated potent HDAC inhibition and anti-inflammatory effects. In this study, we evaluated its anti-cancer activity in vitro and in vivo. MPT0G157 treatment significantly inhibited different tumor growth at submicromolar concentration and was particularly potent in human colorectal cancer (HCT116) cells. Apoptosis and inhibited HDACs activity induced by MPT0G157 was more potent than that by the marketed drugs PXD101 (Belinostat) and SAHA (Vorinostat). In an in vivo model, MPT0G157 markedly inhibited HCT116 xenograft tumor volume and reduced matrigel-induced angiogenesis. The anti-angiogenetic effect of MPT0G157 was found to increase the hyperacetylation of heat shock protein 90 (Hsp90) and promote hypoxia-inducible factor-1α (HIF-1α) degradation followed by down-regulation of vascular endothelial growth factor (VEGF) expression. Our results demonstrate that MPT0G157 has potential as a new drug candidate for cancer therapy. PMID:26087180

  12. Targeting Tumor Vasculature Endothelial Cells and Tumor Cells for Immunotherapy of Human Melanoma in a Mouse Xenograft Model

    NASA Astrophysics Data System (ADS)

    Hu, Zhiwei; Sun, Ying; Garen, Alan

    1999-07-01

    An immunotherapy treatment for cancer that targets both the tumor vasculature and tumor cells has shown promising results in a severe combined immunodeficient mouse xenograft model of human melanoma. The treatment involves systemic delivery of an immunoconjugate molecule composed of a tumor-targeting domain conjugated to the Fc effector domain of human IgG1. The effector domain induces a cytolytic immune response against the targeted cells by natural killer cells and complement. Two types of targeting domains were used. One targeting domain is a human single-chain Fv molecule that binds to a chondroitin sulfate proteoglycan expressed on the surface of most human melanoma cells. Another targeting domain is factor VII (fVII), a zymogen that binds with high specificity and affinity to the transmembrane receptor tissue factor (TF) to initiate the blood coagulation cascade. TF is expressed by endothelial cells lining the tumor vasculature but not the normal vasculature, and also by many types of tumor cells including melanoma. Because the binding of a fVII immunoconjugate to TF might cause disseminated intravascular coagulation, the active site of fVII was mutated to inhibit coagulation without affecting the affinity for TF. The immunoconjugates were encoded as secreted molecules in a replication-defective adenovirus vector, which was injected into the tail vein of severe combined immunodeficient mice. The results demonstrate that a mutated fVII immunoconjugate, administered separately or together with a single-chain Fv immunoconjugate that binds to the tumor cells, can inhibit the growth or cause regression of an established human tumor xenograft. This procedure could be effective in treating a broad spectrum of human solid tumors that express TF on vascular endothelial cells and tumor cells.

  13. Suppression of KSHV-induced angiopoietin-2 inhibits angiogenesis, infiltration of inflammatory cells, and tumor growth.

    PubMed

    Yu, Xiaolan; Sha, Jingfeng; Xiang, Shao; Qin, Sanhai; Conrad, Patricia; Ghosh, Santosh K; Weinberg, Aaron; Ye, Fengchun

    2016-08-01

    Kaposi's sarcoma (KS) is a highly angiogenic and inflammatory neoplasia. The angiogenic and inflammatory cytokine angiopoietin-2 (Ang-2) is strongly expressed in KS due to Kaposi's sarcoma-associated herpesvirus (KSHV) infection. In the present study, we determined how Ang-2 contributes to development of KS by using telomerase-immortalized human umbilical vein endothelial cells (TIVE) as a model, which become malignantly transformed and express increased levels of Ang-2 following KSHV infection. Ang-2 released from TIVE-KSHV cells induces tyrosine phosphorylation of Tie-2 receptor from both human and mouse endothelial cells and promotes angiogenesis in nude mice. Functional inhibition or expressional "knock-down" of Ang-2 in these cells blocks angiogenesis and inhibits tumor growth. Ang-2 suppression also reduces the numbers of infiltrating monocytes/macrophages in tumors. In transwell-based cell migration assays, Ang-2 indeed enhances migration of human monocytes in a dose-dependent manner. These results underscore a pivotal role of KSHV-induced Ang-2 in KS tumor development by promoting both angiogenesis and inflammation. Our data also suggest that selective drug targeting of Ang-2 may be used for treatment of KS. PMID:27294705

  14. Disruption of the protein interaction between FAK and IGF-1R inhibits melanoma tumor growth.

    PubMed

    Ucar, Deniz A; Kurenova, Elena; Garrett, Timothy J; Cance, William G; Nyberg, Carl; Cox, Audrey; Massoll, Nicole; Ostrov, David A; Lawrence, Nicholas; Sebti, Said M; Zajac-Kaye, Maria; Hochwald, Steven N

    2012-09-01

    FAK (focal adhesion kinase) and IGF-1R (insulin-like growth factor receptor-1) directly interact with each other and thereby activate crucial signaling pathways that benefit cancer cells. Inhibition of FAK and IGF-1R function has been shown to significantly decrease cancer cell proliferation and increase sensitivity to chemotherapy and radiation treatment. As a novel approach in human melanoma, we evaluated the effect of a small-molecule compound that disrupts the protein interaction of FAK and IGF-1R. Previously, using virtual screening and functional testing, we identified a lead compound (INT2-31) that targets the known FAK-IGF-1R protein interaction site. We studied the ability of this compound to disrupt FAK-IGF-1R protein interactions, inhibit downstream signaling, decrease human melanoma cell proliferation, alter cell cycle progression, induce apoptosis and decrease tumor growth in vivo. INT2-31 blocked the interaction of FAK and IGF-1R in vitro and in vivo in melanoma cells and tumor xenografts through precluding the activation of IRS-1, leading to reduced phosphorylation of AKT upon IGF-1 stimulation. As a result, INT2-31 significantly inhibited cell proliferation and viability (range 0.05-10 μM). More importantly, 15 mg/kg of INT2-31 given for 21 d via intraperitoneal injection disrupted the interaction of FAK and IGF-1R and effectively decreased phosphorylation of tumor AKT, resulting in significant melanoma tumor regression in vivo. Our data suggest that the FAK-IGF-1R protein interaction is an important target, and disruption of this interaction with a novel small molecule (INT2-31) has potential anti-neoplastic therapeutic effects in human melanoma. PMID:22894899

  15. Anti-Metastatic and Anti-Tumor Growth Effects of Origanum majorana on Highly Metastatic Human Breast Cancer Cells: Inhibition of NFκB Signaling and Reduction of Nitric Oxide Production

    PubMed Central

    Al Dhaheri, Yusra; Attoub, Samir; Arafat, Kholoud; AbuQamar, Synan; Viallet, Jean; Saleh, Alaaeldin; Al Agha, Hala; Eid, Ali; Iratni, Rabah

    2013-01-01

    Background We have recently reported that Origanummajorana exhibits anticancer activity by promoting cell cycle arrest and apoptosis of the metastatic MDA-MB-231 breast cancer cell line. Here, we extended our study by investigating the effect of O. majorana on the migration, invasion and tumor growth of these cells. Results We demonstrate that non-cytotoxic concentrations of O. majorana significantly inhibited the migration and invasion of the MDA-MB-231 cells as shown by wound-healing and matrigel invasion assays. We also show that O. majorana induce homotypic aggregation of MDA-MB-231 associated with an upregulation of E-cadherin protein and promoter activity. Furthermore, we show that O. majorana decrease the adhesion of MDA-MB-231 to HUVECs and inhibits transendothelial migration of MDA-MB-231 through TNF-α-activated HUVECs. Gelatin zymography assay shows that O. majorana suppresses the activities of matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9). ELISA, RT-PCR and Western blot results revealed that O. majorana decreases the expression of MMP-2, MMP-9, urokinase plasminogen activator receptor (uPAR), ICAM-1 and VEGF. Further investigation revealed that O. majorana suppresses the phosphorylation of IκB, downregulates the nuclear level of NFκB and reduces Nitric Oxide (NO) production in MDA-MB-231 cells. Most importantly, by using chick embryo tumor growth assay, we also show that O. majorana promotes inhibition of tumor growth and metastasis in vivo. Conclusion Our findings identify Origanummajorana as a promising chemopreventive and therapeutic candidate that modulate breast cancer growth and metastasis. PMID:23874773

  16. RPA inhibition increases replication stress and suppresses tumor growth.

    PubMed

    Glanzer, Jason G; Liu, Shengqin; Wang, Ling; Mosel, Adam; Peng, Aimin; Oakley, Greg G

    2014-09-15

    The ATR/Chk1 pathway is a critical surveillance network that maintains genomic integrity during DNA replication by stabilizing the replication forks during normal replication to avoid replication stress. One of the many differences between normal cells and cancer cells is the amount of replication stress that occurs during replication. Cancer cells with activated oncogenes generate increased levels of replication stress. This creates an increased dependency on the ATR/Chk1 pathway in cancer cells and opens up an opportunity to preferentially kill cancer cells by inhibiting this pathway. In support of this idea, we have identified a small molecule termed HAMNO ((1Z)-1-[(2-hydroxyanilino)methylidene]naphthalen-2-one), a novel protein interaction inhibitor of replication protein A (RPA), a protein involved in the ATR/Chk1 pathway. HAMNO selectively binds the N-terminal domain of RPA70, effectively inhibiting critical RPA protein interactions that rely on this domain. HAMNO inhibits both ATR autophosphorylation and phosphorylation of RPA32 Ser33 by ATR. By itself, HAMNO treatment creates DNA replication stress in cancer cells that are already experiencing replication stress, but not in normal cells, and it acts synergistically with etoposide to kill cancer cells in vitro and slow tumor growth in vivo. Thus, HAMNO illustrates how RPA inhibitors represent candidate therapeutics for cancer treatment, providing disease selectivity in cancer cells by targeting their differential response to replication stress. Cancer Res; 74(18); 5165-72. ©2014 AACR. PMID:25070753

  17. RPA Inhibition increases Replication Stress and Suppresses Tumor Growth

    PubMed Central

    Glanzer, Jason G.; Liu, Shengqin; Wang, Ling; Mosel, Adam; Peng, Aimin; Oakley, Greg G.

    2014-01-01

    The ATR/Chk1 pathway is a critical surveillance network that maintains genomic integrity during DNA replication by stabilizing the replication forks during normal replication to avoid replication stress. One of the many differences between normal cells and cancer cells is the amount of replication stress that occurs during replication. Cancer cells with activated oncogenes generate increased levels of replication stress. This creates an increased dependency on the ATR/Chk1 pathway in cancer cells and opens up an opportunity to preferentially kill cancer cells by inhibiting this pathway. In support of this idea, we have identified a small molecule termed HAMNO ((1Z)-1-[(2-hydroxyanilino)methylidene]naphthalen-2-one), a novel protein interaction inhibitor of replication protein A (RPA), a protein involved in the ATR/Chk1 pathway. HAMNO selectively binds the N-terminal domain of RPA70, effectively inhibiting critical RPA protein interactions which rely on this domain. HAMNO inhibits both ATR autophosphorylation and phosphorylation of RPA32 Ser33 by ATR. By itself, HAMNO treatment creates DNA replication stress in cancer cells that are already experiencing replication stress, but not in normal cells, and it acts synergistically with etoposide to kill cancer cells in vitro and slow tumor growth in vivo. Thus, HAMNO illustrates how RPA inhibitors represent candidate therapeutics for cancer treatment, providing disease selectivity in cancer cells by targeting their differential response to replication stress. PMID:25070753

  18. The c-Met Inhibitor MSC2156119J Effectively Inhibits Tumor Growth in Liver Cancer Models.

    PubMed

    Bladt, Friedhelm; Friese-Hamim, Manja; Ihling, Christian; Wilm, Claudia; Blaukat, Andree

    2014-01-01

    The mesenchymal-epithelial transition factor (c-Met) is a receptor tyrosine kinase with hepatocyte growth factor (HGF) as its only high-affinity ligand. Aberrant activation of c-Met is associated with many human malignancies, including hepatocellular carcinoma (HCC). We investigated the in vivo antitumor and antimetastatic efficacy of the c-Met inhibitor MSC2156119J (EMD 1214063) in patient-derived tumor explants. BALB/c nude mice were inoculated with MHCC97H cells or with tumor fragments of 10 patient-derived primary liver cancer explants selected according to c-Met/HGF expression levels. MSC2156119J (10, 30, and 100 mg/kg) and sorafenib (50 mg/kg) were administered orally as single-agent treatment or in combination, with vehicle as control. Tumor response, metastases formation, and alpha fetoprotein (AFP) levels were measured. MSC2156119J inhibited tumor growth and induced complete regression in mice bearing subcutaneous and orthotopic MHCC97H tumors. AFP levels were undetectable after 5 weeks of MSC2156119J treatment, and the number of metastatic lung foci was reduced. Primary liver explant models with strong c-Met/HGF activation showed increased responsiveness to MSC2156119J, with MSC2156119J showing similar or superior activity to sorafenib. Tumors characterized by low c-Met expression were less sensitive to MSC2156119J. MSC2156119J was better tolerated than sorafenib, and combination therapy did not improve efficacy. These findings indicate that selective c-Met/HGF inhibition with MSC2156119J is associated with marked regression of c-Met high-expressing tumors, supporting its clinical development as an antitumor treatment for HCC patients with active c-Met signaling. PMID:25256830

  19. Inhibition of cytokine production by a tumor cell product.

    PubMed Central

    Farram, E; Nelson, M; Nelson, D S; Moon, D K

    1982-01-01

    Supernatants from cultured mouse and human tumour cells, but not mouse or guinea-pig fibroblasts, inhibited the production of a lymphokine, macrophage chemotactic factor, by PHA-stimulated mouse spleen cells. The supernatants affected spleen cells from old, but not young, mice. They were most active if added at the start of the spleen cell culture and did not act by binding phytohaemagglutinin (PHA). The active material had an approximate molecular weight, on membrane filtration, of 1000-10,000 and could be bound to and eluted from Con A-Sepharose. Tumour supernatant factor(s) of similar molecular weight inhibited the production of interleukin 1 (lymphocyte activating factor) in response to lipopolysaccharide by stimulated thioglycollate-induced peritoneal exudate macrophages, but not by Corynebacterium parvum-activated macrophages. Similar tumour-produced material has been found to inhibit the early phase of delayed-type hypersensitivity reactions in older mice. It is suggested that this effect is due, at least in part, to inhibition of interleukin 1 production leading to inhibition of lymphokine production. PMID:7047385

  20. Modulation of tumor growth by inhibitory Fcγ receptor expressed by human melanoma cells

    PubMed Central

    Cassard, Lydie; Cohen-Solal, Joël F.G.; Galinha, Annie; Sastre-Garau, Xavier; Mathiot, Claire; Galon, Jérôme; Dorval, Thierry; Bernheim, Alain; Fridman, Wolf H.; Sautès-Fridman, Catherine

    2002-01-01

    The efficacy of anti-tumor IgG reflects the balance between opposing signals mediated by activating and inhibitory Fcγ receptors (FcγRs) expressed by effector cells. Here, we show that human malignant melanoma cells express the inhibitory low-affinity Fcγ receptor FcγRIIB1 in 40% of tested metastases. When melanoma cells were grafted in nude mice, a profound inhibition of FcγRIIB1 tumor growth that required the intracytoplasmic region of the receptor was observed. IgG immune complexes (ICs) may be required for this inhibition, since sera from nude mice bearing tumors contained IgG that decreased the proliferation of FcγRIIB1-positive cells in vitro, and tumor development of FcγRIIB1-positive melanoma lines was not inhibited in antibody-defective severe combined immunodeficiency (SCID) mice. Passive immunization of SCID mice with anti–ganglioside GD2 antibody resulted in significant inhibition of growth of FcγRIIB1-positive tumors in an intracytoplasmic-dependent manner. Altogether, these data suggest that human melanoma cells express biologically active inhibitory FcγRIIB1, which regulates their development upon direct interaction with anti-tumor antibodies. Therefore, FcγR expression on human tumors may be one component of the efficacy of antibody-mediated therapies, and FcγR-positive tumors could be the most sensitive candidates for such treatments. PMID:12438452

  1. Triparanol suppresses human tumor growth in vitro and in vivo

    SciTech Connect

    Bi, Xinyu; Han, Xingpeng; Zhang, Fang; He, Miao; Zhang, Yi; Zhi, Xiu-Yi; Zhao, Hong

    2012-08-31

    Highlights: Black-Right-Pointing-Pointer Demonstrate Triparanol can block proliferation in multiple cancer cells. Black-Right-Pointing-Pointer Demonstrate Triparanol can induce apoptosis in multiple cancer cells. Black-Right-Pointing-Pointer Proved Triparanol can inhibit Hedgehog signaling in multiple cancer cells. Black-Right-Pointing-Pointer Demonstrated Triparanol can impede tumor growth in vivo in mouse xenograft model. -- Abstract: Despite the improved contemporary multidisciplinary regimens treating cancer, majority of cancer patients still suffer from adverse effects and relapse, therefore posing a significant challenge to uncover more efficacious molecular therapeutics targeting signaling pathways central to tumorigenesis. Here, our study have demonstrated that Triparanol, a cholesterol synthesis inhibitor, can block proliferation and induce apoptosis in multiple human cancer cells including lung, breast, liver, pancreatic, prostate cancer and melanoma cells, and growth inhibition can be rescued by exogenous addition of cholesterol. Remarkably, we have proved Triparanol can significantly repress Hedgehog pathway signaling in these human cancer cells. Furthermore, study in a mouse xenograft model of human lung cancer has validated that Triparanol can impede tumor growth in vivo. We have therefore uncovered Triparanol as potential new cancer therapeutic in treating multiple types of human cancers with deregulated Hedgehog signaling.

  2. mTOR and PDGF pathway blockade inhibits liver metastasis of colorectal cancer by modulating the tumor microenvironment.

    PubMed

    Yuge, Ryo; Kitadai, Yasuhiko; Shinagawa, Kei; Onoyama, Mieko; Tanaka, Shinji; Yasui, Wataru; Chayama, Kazuaki

    2015-02-01

    Tumor growth and metastasis are not determined by cancer cells alone but also by a variety of stromal cells, and platelet-derived growth factor receptors (PDGF-Rs) are overexpressed by various stromal cell populations. Activation of PI3K-AKT-mTOR signaling is frequently observed in many cancer types. We investigated whether the mTOR inhibitor everolimus, alone or in combination with the PDGF-R tyrosine kinase inhibitor nilotinib, can inhibit growth and metastasis of human colon cancer. The effects of nilotinib and everolimus on tumor growth and metastasis were examined in an orthotopic mouse model of human colon cancer and a model of liver metastasis. After treatment with nilotinib (versus distilled water), the stromal reaction of xenografts growing in the cecal wall and liver was significantly decreased. After treatment with everolimus, the stromal reaction did not decrease, but tumor cell proliferation and microvessel density decreased. With the two drugs in combination, both stromal reaction and tumor cell proliferation decreased and apoptosis of tumor cells increased, resulting in remarkable inhibition of tumor growth at both the orthotopic and the metastatic site. Concurrent inhibition of tumor cells and activated stromal cells by a PDGF-R tyrosine kinase inhibitor and an mTOR inhibitor used in combination may represent a novel therapeutic approach for colorectal cancer. PMID:25478811

  3. Cimetidine induces apoptosis of human salivary gland tumor cells.

    PubMed

    Fukuda, Masakatsu; Tanaka, Shin; Suzuki, Seiji; Kusama, Kaoru; Kaneko, Tadayoshi; Sakashita, Hideaki

    2007-03-01

    It has been reported that cimetidine, a histamine type-2 receptor (H2R) antagonist, inhibits the growth of glandular tumors such as colorectal cancer. However, its effects against salivary gland tumors are still unknown. We demonstrated previously that human salivary gland tumor (HSG) cells spontaneously express the neural cell adhesion molecule (NCAM) and also that HSG cell proliferation could be controlled via a homophilic (NCAM-NCAM) binding mechanism and that NCAM may be associated with perineural invasion by malignant salivary gland tumors. In the present study, we investigated the effects of cimetidine via the expression of NCAM on tumor growth and perineural/neural invasion in salivary gland tumor cells. Expression of both NCAM mRNA and protein was found to decrease in a dose-dependent manner upon treatment with cimetidine for 24 h. The MTT assay and confocal laser microscopy clearly showed that HSG cells underwent apoptosis after treatment with cimetidine. Activation of caspases 3, 7, 8 and 9 was observed in HSG cells after cimetidine treatment, thus confirming that the apoptosis was induced by the activated caspases. Apaf-1 activity was also detected in HSG cells in a dose-dependent manner after treatment with cimetidine. We also found that the cimetidine-mediated down-regulation of NCAM expression in HSG cells did not occur via blocking of the histamine receptor, even though H2R expression was observed on HSG cells, as two other H2R antagonists, famotidine and ranitidine, did not show similar effects. We demonstrated for the first time that cimetidine can induce significant apoptosis of salivary gland tumor cells, which express NCAM, at least in part by down-regulation of NCAM expression on the cells. These findings suggest that the growth, development and perineural/neural invasion of salivary gland tumor cells can be blocked by cimetidine administration through down-regulation of NCAM expression, as well as induction of apoptosis. PMID:17273750

  4. Arsenic trioxide inhibits tumor cell growth in malignant rhabdoid tumors in vitro and in vivo by targeting overexpressed Gli1.

    PubMed

    Kerl, Kornelius; Moreno, Natalia; Holsten, Till; Ahlfeld, Julia; Mertins, Julius; Hotfilder, Marc; Kool, Marcel; Bartelheim, Kerstin; Schleicher, Sabine; Handgretinger, Rupert; Schüller, Ulrich; Meisterernst, Michael; Frühwald, Michael C

    2014-08-15

    Rhabdoid tumors are highly aggressive tumors occurring in infants and very young children. Despite multimodal and intensive therapy prognosis remains poor. Molecular analyses have uncovered several deregulated pathways, among them the CDK4/6-Rb-, the WNT- and the Sonic hedgehog (SHH) pathways. The SHH pathway is activated in rhabdoid tumors by GLI1 overexpression. Here, we demonstrate that arsenic trioxide (ATO) inhibits tumor cell growth of malignant rhabdoid tumors in vitro and in a mouse xenograft model by suppressing Gli1. Our data uncover ATO as a promising therapeutic approach to improve prognosis for rhabdoid tumor patients. PMID:24420698

  5. Inhibition in the Human Auditory Cortex

    PubMed Central

    Inui, Koji; Nakagawa, Kei; Nishihara, Makoto; Motomura, Eishi; Kakigi, Ryusuke

    2016-01-01

    Despite their indispensable roles in sensory processing, little is known about inhibitory interneurons in humans. Inhibitory postsynaptic potentials cannot be recorded non-invasively, at least in a pure form, in humans. We herein sought to clarify whether prepulse inhibition (PPI) in the auditory cortex reflected inhibition via interneurons using magnetoencephalography. An abrupt increase in sound pressure by 10 dB in a continuous sound was used to evoke the test response, and PPI was observed by inserting a weak (5 dB increase for 1 ms) prepulse. The time course of the inhibition evaluated by prepulses presented at 10–800 ms before the test stimulus showed at least two temporally distinct inhibitions peaking at approximately 20–60 and 600 ms that presumably reflected IPSPs by fast spiking, parvalbumin-positive cells and somatostatin-positive, Martinotti cells, respectively. In another experiment, we confirmed that the degree of the inhibition depended on the strength of the prepulse, but not on the amplitude of the prepulse-evoked cortical response, indicating that the prepulse-evoked excitatory response and prepulse-evoked inhibition reflected activation in two different pathways. Although many diseases such as schizophrenia may involve deficits in the inhibitory system, we do not have appropriate methods to evaluate them; therefore, the easy and non-invasive method described herein may be clinically useful. PMID:27219470

  6. A recombinant decoy comprising EGFR and ErbB-4 inhibits tumor growth and metastasis

    PubMed Central

    Lindzen, Moshit; Carvalho, Silvia; Starr, Alex; Ben-Chetrit, Nir; Pradeep, Chaluvally-Raghavan; Köstler, Wolfgang J.; Rabinkov, Aaron; Lavi, Sara; Bacus, Sarah S.; Yarden, Yosef

    2011-01-01

    EGF-like growth factors control tumor progression, as well as evasion from the toxic effects of chemotherapy. Accordingly, antibodies targeting the cognate receptors, such as EGFR/ErbB-1 and the co-receptor HER2/ErbB-2, are widely used to treat cancer patients, but agents that target the EGF-like growth factors are not available. To circumvent the existence of 11 distinct ErbB ligands, we constructed a soluble fusion protein (hereinafter: TRAP-Fc) comprising truncated extracellular domains of EGFR/ErbB-1 and ErbB-4. The recombinant TRAP-Fc retained high affinity ligand binding to EGF-like growth factors and partially inhibited growth of a variety of cultured tumor cells. Consistently, TRAP-Fc displayed an inhibitory effect in xenograft models of human cancer, as well as synergy with chemotherapy. Additionally, TRAP-Fc inhibited invasive growth of mammary tumor cells and reduced their metastatic seeding in the lungs of animals. Taken together, the activities displayed by TRAP-Fc reinforce critical roles of EGF-like growth factors in tumor progression, and they warrant further tests of TRAP-Fc in pre-clinical models. PMID:22105361

  7. Itraconazole inhibits angiogenesis and tumor growth in non-small cell lung cancer

    PubMed Central

    Aftab, Blake T.; Dobromilskaya, Irina; Liu, Jun O.; Rudin, Charles M.

    2011-01-01

    The anti-angiogenic agent bevacizumab has been approved for the treatment of non-small cell lung cancer, although the survival benefit associated with this agent is marginal, and toxicities and cost are substantial. A recent screen for selective inhibitors of endothelial cell proliferation identified the oral anti-fungal drug itraconazole as a novel agent with potential anti-angiogenic activity. Here we define and characterize the anti-angiogenic and anti-cancer activities of itraconazole in relevant preclinical models of angiogenesis and lung cancer. Itraconazole consistently demonstrated potent, specific, and dose-dependent inhibition of endothelial cell proliferation, migration, and tube formation in response to both vascular endothelial growth factor (VEGF)- and basic fibroblast growth factor (bFGF)-mediated angiogenic stimulation. In vivo, using primary xenograft models of human non-small cell lung cancer, oral itraconazole showed single agent growth-inhibitory activity associated with induction of tumor HIF1α expression and marked inhibition of tumor vascularity. Itraconazole significantly enhanced the anti-tumor efficacy of the chemotherapeutic agent cisplatin in the same model systems. Taken together, these data suggest that itraconazole has potent and selective inhibitory activity against multiple key aspects of tumor-associated angiogenesis in vitro and in vivo, and strongly support clinical translation of its use. Based on these observations we have initiated a randomized phase II study comparing the efficacy of standard cytotoxic therapy with or without daily oral itraconazole in patients with recurrent metastatic non-small cell lung cancer. PMID:21896639

  8. Inhibition of cystine uptake disrupts the growth of primary brain tumors.

    PubMed

    Chung, Wook Joon; Lyons, Susan A; Nelson, Gina M; Hamza, Hashir; Gladson, Candece L; Gillespie, G Yancey; Sontheimer, Harald

    2005-08-01

    Glial cells play an important role in sequestering neuronally released glutamate via Na+-dependent transporters. Surprisingly, these transporters are not operational in glial-derived tumors (gliomas). Instead, gliomas release glutamate, causing excitotoxic death of neurons in the vicinity of the tumor. We now show that glutamate release from glioma cells is an obligatory by-product of cellular cystine uptake via system xc-, an electroneutral cystine-glutamate exchanger. Cystine is an essential precursor for the biosynthesis of glutathione, a major redox regulatory molecule that protects cells from endogenously produced reactive oxygen species (ROS). Glioma cells, but not neurons or astrocytes, rely primarily on cystine uptake via system xc- for their glutathione synthesis. Inhibition of system xc- causes a rapid depletion of glutathione, and the resulting loss of ROS defense causes caspase-mediated apoptosis. Glioma cells can be rescued if glutathione status is experimentally restored or if glutathione is substituted by alternate cellular antioxidants, confirming that ROS are indeed mediators of cell death. We describe two potent drugs that permit pharmacological inhibition of system xc-. One of these drugs, sulfasalazine, is clinically used to treat inflammatory bowel disease and rheumatoid arthritis. Sulfasalazine was able to reduce glutathione levels in tumor tissue and slow tumor growth in vivo in a commonly used intracranial xenograft animal model for human gliomas when administered by intraperitoneal injection. These data suggest that inhibition of cystine uptake into glioma cells through the pharmacological inhibition of system xc- may be a viable therapeutic strategy with a Food and Drug Administration-approved drug already in hand. PMID:16079392

  9. Cabozantinib inhibits prostate cancer growth and prevents tumor-induced bone lesions

    PubMed Central

    Dai, Jinlu; Zhang, Honglai; Karatsinides, Andreas; Keller, Jill M.; Kozloff, Kenneth M.; Aftab, Dana T.; Schimmoller, Frauke; Keller, Evan T.

    2013-01-01

    Purpose Cabozantinib, an orally available multi-tyrosine kinase inhibitor with activity against MET and vascular endothelial growth factor receptor 2 (VEGFR2), induces resolution of bone scan lesions in men with castration-resistant prostate cancer bone metastases. The purpose of this study was to determine whether cabozantinib elicited a direct anti-tumor effect, an indirect effect through modulating bone, or both. Experimental Design Using human prostate cancer xenograft studies in mice we determined cabozantinib's impact on tumor growth in soft tissue and bone. In vitro studies with cabozantinib were performed using (1) prostate cancer cell lines to evaluate its impact on cell growth, invasive ability and MET and (2) osteoblast cell lines to evaluate its impact on viability and differentiation and VEGFR2. Results Cabozantinib inhibited progression of multiple prostate cancer cell lines (Ace-1,C4-2B, and LuCaP 35) in bone metastatic and soft tissue murine models of prostate cancer, except for PC-3 prostate cancer cells in which it inhibited only subcutaneous growth. Cabozantinib directly inhibited prostate cancer cell viability and induced apoptosis in vitro and in vivo and inhibited cell invasion in vitro. Cabozantinib had a dose-dependent biphasic effect on osteoblast activity and inhibitory effect on osteoclast production in vitro, that was reflected in vivo. It blocked MET and VEGFR2 phosphorylation in prostate cancer cells and osteoblast-like cells, respectively. Conclusion These data indicate that cabozantinib has direct anti-tumor activity; and that its ability to modulate osteoblast activity may contribute to its anti-tumor efficacy. PMID:24097861

  10. Imatinib and Dasatinib Inhibit Hemangiosarcoma and Implicate PDGFR-β and Src in Tumor Growth.

    PubMed

    Dickerson, Erin B; Marley, Kevin; Edris, Wade; Tyner, Jeffrey W; Schalk, Vidya; Macdonald, Valerie; Loriaux, Marc; Druker, Brian J; Helfand, Stuart C

    2013-04-01

    Hemangiosarcoma, a natural model of human angiosarcoma, is an aggressive vascular tumor diagnosed commonly in dogs. The documented expression of several receptor tyrosine kinases (RTKs) by these tumors makes them attractive targets for therapeutic intervention using tyrosine kinase inhibitors (TKIs). However, we possess limited knowledge of the effects of TKIs on hemangiosarcoma as well as other soft tissue sarcomas. We report here on the use of the TKIs imatinib and dasatinib in canine hemangiosarcoma and their effects on platelet-derived growth factor receptor β (PDGFR-β) and Src inhibition. Both TKIs reduced cell viability, but dasatinib was markedly more potent in this regard, mediating cytotoxic effects orders of magnitude greater than imatinib. Dasatinib also inhibited the phosphorylation of the shared PDGFR-β target at a concentration approximately 1000 times less than that needed by imatinib and effectively blocked Src phosphorylation. Both inhibitors augmented the response to doxorubicin, suggesting that clinical responses likely will be improved using both drugs in combination; however, dasatinib was significantly (P < .05) more effective in this context. Despite the higher concentrations needed in cell-based assays, imatinib significantly inhibited tumor growth (P < .05) in a tumor xenograft model, highlighting that disruption of PDGFR-β/PDGF signaling may be important in targeting the angiogenic nature of these tumors. Treatment of a dog with spontaneously occurring hemangiosarcoma established that clinically achievable doses of dasatinib may be realized in dogs and provides a means to investigate the effect of TKIs on soft tissue sarcomas in a large animal model. PMID:23544168

  11. A tissue-engineered therapeutic device inhibits tumor growth in vitro and in vivo.

    PubMed

    Sun, Ming; Wang, Miao; Chen, Muwan; Dagnaes-Hansen, Frederik; Le, Dang Quang Svend; Baatrup, Anette; Horsman, Michael R; Kjems, Jørgen; Bünger, Cody Eric

    2015-05-01

    Bone metastasis is one of the leading causes of death in breast cancer patients. The current treatment is performed as a palliative therapy and the adverse side effects can compromise the patients' quality of life. In order to both effectively treat bone metastasis and avoid the limitation of current strategies, we have invented a drug eluting scaffold with clay matrix release doxorubicin (DESCLAYMR_DOX) to mechanically support the structure after resecting the metastatic tissue while also releasing the anticancer drug doxorubicin which supplements growth inhibition and elimination of the remaining tumor cells. We have previously demonstrated that this device has the capacity to regenerate the bone and provide sustained release of the anticancer drug in vitro. In this study, we focus on the ability of the device to inhibit cancer cell growth in vitro as well as in vivo. Drug-release kinetics was investigated and the cell viability test showed that the tumor inhibitory effect is sustained for up to 4weeks in vitro. Subcutaneous implantation of DESCLAYMR_DOX in athymic mice resulted in significant growth inhibition of human tumor xenografts of breast origin and decelerated multi-organ metastasis formation. Fluorescence images, visualizing doxorubicin, showed a sustained drug release from the DESCLAYMR device in vivo. Furthermore, local use of DESCLAYMR_DOX implantation reduced the incidence of doxorubicin's cardio-toxicity. These results suggest that DESCLAYMR_DOX can be used in reconstructive surgery to support the structure after bone tumor resection and facilitate a sustained release of anticancer drugs in order to prevent tumor recurrence. PMID:25686557

  12. Genetically engineered endostatin-lidamycin fusion proteins effectively inhibit tumor growth and metastasis

    PubMed Central

    2013-01-01

    Background Endostatin (ES) inhibits endothelial cell proliferation, migration, invasion, and tube formation. It also shows antiangiogenesis and antitumor activities in several animal models. Endostatin specifically targets tumor vasculature to block tumor growth. Lidamycin (LDM), which consists of an active enediyne chromophore (AE) and a non-covalently bound apo-protein (LDP), is a member of chromoprotein family of antitumor antibiotics with extremely potent cytotoxicity to cancer cells. Therefore, we reasoned that endostatin-lidamycin (ES-LDM) fusion proteins upon energizing with enediyne chromophore may obtain the combined capability targeting tumor vasculature and tumor cell by respective ES and LDM moiety. Methods In this study, we designed and obtained two new endostatin-based fusion proteins, endostatin-LDP (ES-LDP) and LDP-endostatin (LDP-ES). In vitro, the antiangiogenic effect of fusion proteins was determined by the wound healing assay and tube formation assay and the cytotoxicity of their enediyne-energized analogs was evaluated by CCK-8 assay. Tissue microarray was used to analyze the binding affinity of LDP, ES or ES-LDP with specimens of human lung tissue and lung tumor. The in vivo efficacy of the fusion proteins was evaluated with human lung carcinoma PG-BE1 xenograft and the experimental metastasis model of 4T1-luc breast cancer. Results ES-LDP and LDP-ES disrupted the formation of endothelial tube structures and inhibited endothelial cell migration. Evidently, ES-LDP accumulated in the tumor and suppressed tumor growth and metastasis. ES-LDP and ES show higher binding capability than LDP to lung carcinoma; in addition, ES-LDP and ES share similar binding capability. Furthermore, the enediyne-energized fusion protein ES-LDP-AE demonstrated significant efficacy against lung carcinoma xenograft in athymic mice. Conclusions The ES-based fusion protein therapy provides some fundamental information for further drug development. Targeting both tumor

  13. Inhibition of Rho-Associated Kinase 1/2 Attenuates Tumor Growth in Murine Gastric Cancer.

    PubMed

    Hinsenkamp, Isabel; Schulz, Sandra; Roscher, Mareike; Suhr, Anne-Maria; Meyer, Björn; Munteanu, Bogdan; Fuchser, Jens; Schoenberg, Stefan O; Ebert, Matthias P A; Wängler, Björn; Hopf, Carsten; Burgermeister, Elke

    2016-08-01

    Gastric cancer (GC) remains a malignant disease with high mortality. Patients are frequently diagnosed in advanced stages where survival prognosis is poor. Thus, there is high medical need to find novel drug targets and treatment strategies. Recently, the comprehensive molecular characterization of GC subtypes revealed mutations in the small GTPase RHOA as a hallmark of diffuse-type GC. RHOA activates RHO-associated protein kinases (ROCK1/2) which regulate cell contractility, migration and growth and thus may play a role in cancer. However, therapeutic benefit of RHO-pathway inhibition in GC has not been shown so far. The ROCK1/2 inhibitor 1-(5-isoquinoline sulfonyl)-homopiperazine (HA-1077, fasudil) is approved for cerebrovascular bleeding in patients. We therefore investigated whether fasudil (i.p., 10 mg/kg per day, 4 times per week, 4 weeks) inhibits tumor growth in a preclinical model of GC. Fasudil evoked cell death in human GC cells and reduced the tumor size in the stomach of CEA424-SV40 TAg transgenic mice. Small animal PET/CT confirmed preclinical efficacy. Mass spectrometry imaging identified a translatable biomarker for mouse GC and suggested rapid but incomplete in situ distribution of the drug to gastric tumor tissue. RHOA expression was increased in the neoplastic murine stomach compared with normal non-malignant gastric tissue, and fasudil reduced (auto) phosphorylation of ROCK2 at THR249 in vivo and in human GC cells in vitro. In sum, our data suggest that RHO-pathway inhibition may constitute a novel strategy for treatment of GC and that enhanced distribution of future ROCK inhibitors into tumor tissue may further improve efficacy. PMID:27566106

  14. BROMODICHLOROMETHANE INHIBITS HUMAN PLACENTAL TROPHOBLAST DIFFERENTIATION

    EPA Science Inventory

    BROMODICHLOROMETHANE INHIBITS HUMAN PLACENTAL
    TROPHOBLAST DIFFERENTIATION
    Jiangang Chen, Twanda L. Thirkill, Peter N. Lohstroh, Susan R. Bielmeier, Michael
    G. Narotsky, Deborah S. Best, Randy A. Harrison, Kala Natarajan, Rex A. Pegram,
    Bill L. Lasley, and Gordon C. Do...

  15. Dietary phenethyl isothiocyanate inhibition of androgen-responsive LNCaP prostate cancer cell tumor growth correlates with decreased angiogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phenethyl isothiocyanate (PEITC), found in certain cruciferous vegetables, has antitumor activity in several cancer models, including prostate cancer. In our xenograft model, dietary administration of PEITC (100-150 mg/kg/d) inhibited androgen-responsive LNCaP human prostate cancer cell tumor growth...

  16. Canonical Wnt/β-catenin signaling drives human schwann cell transformation, progression, and tumor maintenance.

    PubMed

    Watson, Adrienne L; Rahrmann, Eric P; Moriarity, Branden S; Choi, Kwangmin; Conboy, Caitlin B; Greeley, Andrew D; Halfond, Amanda L; Anderson, Leah K; Wahl, Brian R; Keng, Vincent W; Rizzardi, Anthony E; Forster, Colleen L; Collins, Margaret H; Sarver, Aaron L; Wallace, Margaret R; Schmechel, Stephen C; Ratner, Nancy; Largaespada, David A

    2013-06-01

    Genetic changes required for the formation and progression of human Schwann cell tumors remain elusive. Using a Sleeping Beauty forward genetic screen, we identified several genes involved in canonical Wnt signaling as potential drivers of benign neurofibromas and malignant peripheral nerve sheath tumors (MPNSTs). In human neurofibromas and MPNSTs, activation of Wnt signaling increased with tumor grade and was associated with downregulation of β-catenin destruction complex members or overexpression of a ligand that potentiates Wnt signaling, R-spondin 2 (RSPO2). Induction of Wnt signaling was sufficient to induce transformed properties in immortalized human Schwann cells, and downregulation of this pathway was sufficient to reduce the tumorigenic phenotype of human MPNST cell lines. Small-molecule inhibition of Wnt signaling effectively reduced the viability of MPNST cell lines and synergistically induced apoptosis when combined with an mTOR inhibitor, RAD-001, suggesting that Wnt inhibition represents a novel target for therapeutic intervention in Schwann cell tumors. PMID:23535903

  17. Inhibition of the autophagy flux by gingerol enhances TRAIL-induced tumor cell death.

    PubMed

    Nazim, Uddin Md; Jeong, Jae-Kyo; Seol, Jae-Won; Hur, Jin; Eo, Seong-Kug; Lee, John-Hwa; Park, Sang-Youel

    2015-05-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a primary anticancer agent and a member of the tumor necrosis factor family that selectively induces apoptosis in various tumor cells, but not in normal cells. Gingerol is a major ginger component with anti-inflammatory and anti‑tumorigenic activities. Autophagy flux is the complete process of autophagy, in which the autophagosomes are lysed by lysosomes. The role of autophagy in cell death or cell survival is controversial. A549 adenocarcinoma cells are TRAIL-resistant. In the present study, we showed that treatment with TRAIL slightly induced cell death, but gingerol treatment enhanced the TRAIL-induced cell death in human lung cancer cells. The combination of gingerol and TRAIL increased accumulation of microtubule-associated protein light chain 3-II and p62, confirming the inhibited autophagy flux. Collectively, our results suggest that gingerol sensitizes human lung cancer cells to TRAIL-induced apoptosis by inhibiting the autophagy flux. PMID:25813697

  18. Anti-tumor activity of benzylideneacetophenone derivatives via proteasomal inhibition in prostate cancer cells.

    PubMed

    Lee, Yun-hee; Yun, Jaesuk; Jung, Jae-Chul; Oh, Seikwan; Jung, Young-Suk

    2016-05-01

    A number of some chalcone derivatives possess promising biological properties including anti-inflammation, anti-oxidant, and anti-tumor activity. Although it has been shown that some derivatives of chalcone induce apoptosis in different kinds of cancer cells, the involved mechanism of action is not well defined. The purpose of this study is to investigate the primary target of a benzylideneacetophenone derivative (JC3), which is a synthetic compound derived from the chalcone family, in human cancer, using prostate cancer cells as a working model. Herein, we show that JC3 inhibits proteasomal activity as indicated by both in vitro and in cell-based assays. Especially, the JC3-dimer was more potent than monomer in the aspect of proteasome inhibition, which induced apoptosis significantly in the prostate cancer cells. Owing to the critical roles of the proteasome in the biology of human tumor progression, invasion, and metastasis, these findings give an important clue for the development of novel anti-tumor agents. PMID:27348972

  19. Morelloflavone, a biflavonoid, inhibits tumor angiogenesis by targeting rho GTPases and extracellular signal-regulated kinase signaling pathways.

    PubMed

    Pang, Xiufeng; Yi, Tingfang; Yi, Zhengfang; Cho, Sung Gook; Qu, Weijing; Pinkaew, Decha; Fujise, Ken; Liu, Mingyao

    2009-01-15

    Morelloflavone, a biflavonoid extracted from Garcinia dulcis, has shown antioxidative, antiviral, and anti-inflammatory properties. However, the function and the mechanism of this compound in cancer treatment and tumor angiogenesis have not been elucidated to date. In this study, we postulated that morelloflavone might have the ability to inhibit angiogenesis, the pivotal step in tumor growth, invasiveness, and metastasis. We showed that morelloflavone could inhibit vascular endothelial growth factor (VEGF)-induced cell proliferation, migration, invasion, and capillary-like tube formation of primary cultured human umbilical vascular endothelial cells in a dose-dependent manner. Morelloflavone effectively inhibited microvessel sprouting of endothelial cells in the mouse aortic ring assay and the formation of new blood microvessels induced by VEGF in the mouse Matrigel plug assay. Furthermore, morelloflavone inhibited tumor growth and tumor angiogenesis of prostate cancer cells (PC-3) in xenograft mouse tumor model in vivo, suggesting that morelloflavone inhibited tumorigenesis by targeting angiogenesis. To understand the underlying mechanism of morelloflavone on the inhibitory effect of tumor growth and angiogenesis, we showed that morelloflavone could inhibit the activation of both RhoA and Rac1 GTPases but have little effect on the activation of Cdc42 GTPase. Additionally, morelloflavone inhibited the phosphorylation and activation of Raf/mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase/ERK pathway kinases without affecting VEGF receptor 2 activity. Together, our results indicate that morelloflavone exerts antiangiogenic action by targeting the activation of Rho-GTPases and ERK signaling pathways. These findings are the first to reveal the novel functions of morelloflavone in tumor angiogenesis and its molecular basis for the anticancer action. PMID:19147565

  20. Antagonism of sphingosine-1-phosphate receptors by FTY720 inhibits angiogenesis and tumor vascularization.

    PubMed

    LaMontagne, Kenneth; Littlewood-Evans, Amanda; Schnell, Christian; O'Reilly, Terence; Wyder, Lorenza; Sanchez, Teresa; Probst, Beatrice; Butler, Jeannene; Wood, Alexander; Liau, Gene; Billy, Eric; Theuer, Andreas; Hla, Timothy; Wood, Jeanette

    2006-01-01

    FTY720, a potent immunomodulator, becomes phosphorylated in vivo (FTY-P) and interacts with sphingosine-1-phosphate (S1P) receptors. Recent studies showed that FTY-P affects vascular endothelial growth factor (VEGF)-induced vascular permeability, an important aspect of angiogenesis. We show here that FTY720 has antiangiogenic activity, potently abrogating VEGF- and S1P-induced angiogenesis in vivo in growth factor implant and corneal models. FTY720 administration tended to inhibit primary and significantly inhibited metastatic tumor growth in a mouse model of melanoma growth. In combination with a VEGFR tyrosine kinase inhibitor PTK787/ZK222584, FTY720 showed some additional benefit. FTY720 markedly inhibited tumor-associated angiogenesis, and this was accompanied by decreased tumor cell proliferation and increased apoptosis. In transfected HEK293 cells, FTY-P internalized S1P1 receptors, inhibited their recycling to the cell surface, and desensitized S1P receptor function. Both FTY720 and FTY-P apparently failed to impede VEGF-produced increases in mitogen-activated protein kinase activity in human umbilical vascular endothelial cells (HUVEC), and unlike its activity in causing S1PR internalization, FTY-P did not result in a decrease of surface VEGFR2 levels in HUVEC cells. Pretreatment with FTY720 or FTY-P prevented S1P-induced Ca2+ mobilization and migration in vascular endothelial cells. These data show that functional antagonism of vascular S1P receptors by FTY720 potently inhibits angiogenesis; therefore, this may provide a novel therapeutic approach for pathologic conditions with dysregulated angiogenesis. PMID:16397235

  1. Small rho GTPases mediate tumor-induced inhibition of endocytic activity of dendritic cells.

    PubMed

    Tourkova, Irina L; Shurin, Galina V; Wei, Sheng; Shurin, Michael R

    2007-06-15

    The generation, maturation, and function of dendritic cells (DC) have been shown to be markedly compromised in the tumor microenvironment in animals and humans. However, the molecular mechanisms and intracellular pathways involved in the regulation of the DC system in cancer are not yet fully understood. Recently, we have reported on the role of the small Rho GTPase family members Cdc42, Rac1, and RhoA in regulating DC adherence, motility, and Ag presentation. To investigate involvement of small Rho GTPases in dysregulation of DC function by tumors, we next evaluated how Cdc42, Rac1, and RhoA regulated endocytic activity of DC in the tumor microenvironment. We revealed a decreased uptake of dextran 40 and polystyrene beads by DC generated in the presence of different tumor cell lines, including RM1 prostate, MC38 colon, 3LL lung, and B7E3 oral squamous cell carcinomas in vitro and by DC prepared from tumor-bearing mice ex vivo. Impaired endocytic activity of DC cocultured with tumor cells was associated with decreased levels of active Cdc42 and Rac1. Transduction of DC with the dominant negative Cdc42 and Rac1 genes also led to reduced phagocytosis and receptor-mediated endocytosis. Furthermore, transduction of DC with the constitutively active Cdc42 and Rac1 genes restored endocytic activity of DC that was inhibited by the tumors. Thus, our results suggest that tumor-induced dysregulation of endocytic activity of DC is mediated by reduced activity of several members of the small Rho GTPase family, which might serve as new targets for improving the efficacy of DC vaccines. PMID:17548616

  2. Tumor promotion and inhibition by phenobarbital in livers of conditional Apc-deficient mice.

    PubMed

    Braeuning, Albert; Gavrilov, Alina; Geissler, Miriam; Wenz, Christine; Colnot, Sabine; Templin, Markus F; Metzger, Ute; Römer, Michael; Zell, Andreas; Schwarz, Michael

    2016-06-01

    Activation of Wnt/β-catenin signaling is important for human and rodent hepatocarcinogenesis. In mice, the tumor promoter phenobarbital (PB) selects for hepatocellular tumors with activating β-catenin mutations via constitutive androstane receptor activation. PB-dependent tumor promotion was studied in mice with genetic inactivation of Apc, a negative regulator of β-catenin, to circumvent the problem of randomly induced mutations by chemical initiators and to allow monitoring of PB- and Wnt/β-catenin-dependent tumorigenesis in the absence of unknown genomic alterations. Moreover, the study was designed to investigate PB-induced proliferation of liver cells with activated β-catenin. PB treatment provided Apc-deficient hepatocytes with only a minor proliferative advantage, and additional connexin 32 deficiency did not affect the proliferative response. PB significantly promoted the outgrowth of Apc-deficient hepatocellular adenoma (HCA), but simultaneously inhibited the formation of Apc-deficient hepatocellular carcinoma (HCC). The probability of tumor promotion by PB was calculated to be much lower for hepatocytes with loss of Apc, as compared to mutational β-catenin activation. Comprehensive transcriptomic and phosphoproteomic characterization of HCA and HCC revealed molecular details of the two tumor types. HCC were characterized by a loss of differentiated hepatocellular gene expression, enhanced proliferative signaling, and massive over-activation of Wnt/β-catenin signaling. In conclusion, PB exerts a dual role in liver tumor formation by promoting the growth of HCA but inhibiting the growth of HCC. Data demonstrate that one and the same compound can produce opposite effects on hepatocarcinogenesis, depending on context, highlighting the necessity to develop a more differentiated view on the tumorigenicity of this model compound. PMID:26838046

  3. Recombinant TIMP-1-GPI inhibits growth of fibrosarcoma and enhances tumor sensitivity to doxorubicin.

    PubMed

    Bao, Q; Niess, H; Djafarzadeh, R; Zhao, Y; Schwarz, B; Angele, M K; Jauch, K-W; Nelson, P J; Bruns, C J

    2014-09-01

    Fibrosarcomas show a high incidence of recurrence and general resistance to apoptosis. Limiting tumor regrowth and increasing their sensitivity to chemotherapy and apoptosis represent key issues in developing more effective treatments of these tumors. Tissue inhibitor of metalloproteinase 1 (TIMP-1) broadly blocks matrix metalloproteinase (MMP) activity and can moderate tumor growth and metastasis. We previously described generation of a recombinant fusion protein linking TIMP-1 to glycosylphophatidylinositol (GPI) anchor (TIMP-1-GPI) that efficiently directs the inhibitor to cell surfaces. In the present report, we examined the effect of TIMP-1-GPI treatment on fibrosarcoma biology. Exogenously applied TIMP-1-GPI efficiently incorporated into surface membranes of human HT1080 fibrosarcoma cells. It inhibited their proliferation, migration, suppressed cancer cell clone formation, and enhanced apoptosis. Doxorubicin, the standard chemotherapeutic drug for fibrosarcoma, was tested alone or in combination with TIMP-1-GPI. In parallel, the influence of treatment on HT1080 side population cells (exhibiting tumor stem cell-like characteristics) was investigated using Hoechst 33342 staining. The sequential combination of TIMP-1-GPI and doxorubicin showed more than additive effects on apoptosis, while TIMP-1-GPI treatment alone effectively decreased "stem-cell like" side population cells of HT1080. TIMP-1-GPI treatment was validated using HT1080 fibrosarcoma murine xenografts. Growing tumors treated with repeated local injections of TIMP-1-GPI showed dramatically inhibited fibrosarcoma growth and reduced angiogenesis. Intraoperative peritumoral application of GPI-anchored TIMP-1 as an adjuvant to surgery may help maintain tumor control by targeting microscopic residual fibrosarcoma cells and increasing their sensitivity to chemotherapy. PMID:23934106

  4. CCR-08-0827 Version 2 Targeted inhibition of cyclic AMP phosphodiesterase-4 promotes brain tumor regression

    PubMed Central

    Goldhoff, Patricia; Warrington, Nicole; Limbrick, David D.; Hope, Andrew; Woerner, B. Mark; Jackson, Erin; Perry, Arie; Piwnica-Worms, David; Rubin, Joshua B.

    2008-01-01

    Statement of Clinical Relevance Therapies that can overcome the resistance of malignant brain tumors would be a major clinical advance. Here, we investigate the role of cAMP Phosphodiesterase-4 in stimulating brain tumor growth and the therapeutic utility of cAMP Phosphodiesterase-4 inhibition in the treatment of malignant brain tumors. Cyclic AMP Phosphodiesterase-4 was widely expressed in human brain tumors of glial and neuronal lineage, and forced expression of PDE4A1 accelerated intracranial glioblastoma and medulloblastoma xenograft growth. Moreover, targeted inhibition of PDE4, in combination with standard radiation and chemotherapy, induced a unique regression of established intracranial glioblastoma xenografts. These findings identify PDE4 as a novel molecular target for brain tumor therapy and indicate that PDE4 inhibition should be evaluated in clinical trials for malignant brain tumors. Purpose As favorable outcomes from malignant brain tumors remain limited by poor survival and treatment-related toxicity, novel approaches to cure are essential. Previously, we identified the cyclic AMP phosphodiesterase-4 (PDE4) inhibitor Rolipram as a potent anti-tumor agent. Here, we investigate the role of PDE4 in brain tumors and examine the utility of PDE4 as a therapeutic target. Experimental Design Immunohistochemistry was used to evaluate the expression pattern of a subfamily of PDE4, PDE4A, in multiple brain tumor types. To evaluate the effect of PDE4A on growth, a brain-specific isoform, PDE4A1 was overexpressed in xenografts of Daoy medulloblastoma and U87 glioblastoma cells. To determine therapeutic potential of PDE4 inhibition, Rolipram, temozolomide, and radiation were tested alone and in combination on mice bearing intracranial U87 xenografts. Results We found that PDE4A is expressed in medulloblastoma, glioblastoma, oligodendroglioma, ependymoma and meningioma. Moreover, when PDE4A1 was overexpressed in Daoy medulloblastoma and U87 glioblastoma cells, in

  5. Dual inhibition of cyclooxygenase-2 and soluble epoxide hydrolase synergistically suppresses primary tumor growth and metastasis

    PubMed Central

    Zhang, Guodong; Panigrahy, Dipak; Hwang, Sung Hee; Yang, Jun; Mahakian, Lisa M.; Wettersten, Hiromi I.; Liu, Jun-Yan; Wang, Yanru; Ingham, Elizabeth S.; Tam, Sarah; Kieran, Mark W.; Weiss, Robert H.; Ferrara, Katherine W.; Hammock, Bruce D.

    2014-01-01

    Prostaglandins derived from the cyclooxygenase (COX) pathway and epoxyeicosatrienoic acids (EETs) from the cytochrome P450/soluble epoxide hydrolase (sEH) pathway are important eicosanoids that regulate angiogenesis and tumorigenesis. COX-2 inhibitors, which block the formation of prostaglandins, suppress tumor growth, whereas sEH inhibitors, which increase endogenous EETs, stimulate primary tumor growth and metastasis. However, the functional interactions of these two pathways in cancer are unknown. Using pharmacological inhibitors as probes, we show here that dual inhibition of COX-2 and sEH synergistically inhibits primary tumor growth and metastasis by suppressing tumor angiogenesis. COX-2/sEH dual pharmacological inhibitors also potently suppress primary tumor growth and metastasis by inhibiting tumor angiogenesis via selective inhibition of endothelial cell proliferation. These results demonstrate a critical interaction of these two lipid metabolism pathways on tumorigenesis and suggest dual inhibition of COX-2 and sEH as a potential therapeutic strategy for cancer therapy. PMID:25024195

  6. A soluble form of GAS1 inhibits tumor growth and angiogenesis in a triple negative breast cancer model.

    PubMed

    Jiménez, Adriana; López-Ornelas, Adolfo; Estudillo, Enrique; González-Mariscal, Lorenza; González, Rosa O; Segovia, José

    2014-10-01

    We previously demonstrated the capacity of GAS1 (Growth Arrest Specific 1) to inhibit the growth of gliomas by blocking the GDNF-RET signaling pathway. Here, we show that a soluble form of GAS1 (tGAS1), decreases the number of viable MDA MB 231 human breast cancer cells, acting in both autocrine and paracrine manners when secreted from producing cells. Moreover, tGAS1 inhibits the growth of tumors implanted in female nu/nu mice through a RET-independent mechanism which involves interfering with the Artemin (ARTN)-GFRα3-(GDNF Family Receptor alpha 3) mediated intracellular signaling and the activation of ERK. In addition, we observed that the presence of tGAS1 reduces the vascularization of implanted tumors, by preventing the migration of endothelial cells. The present results support a potential adjuvant role for tGAS1 in the treatment of breast cancer, by detaining tumor growth and inhibiting angiogenesis. PMID:24992044

  7. CDC42 inhibition suppresses progression of incipient intestinal tumors

    PubMed Central

    Sakamori, Ryotaro; Yu, Shiyan; Zhang, Xiao; Hoffman, Andrew; Sun, Jiaxin; Das, Soumyashree; Vedula, Pavan; Li, Guangxun; Fu, Jiang; Walker, Francesca; Yang, Chung S.; Yi, Zheng; Hsu, Wei; Yu, Da-Hai; Shen, Lanlan; Rodriguez, Alexis J.; Taketo, Makoto M.; Bonder, Edward M.; Verzi, Michael P.; Gao, Nan

    2014-01-01

    Mutations in the APC or β-catenin genes are well established initiators of colorectal cancer (CRC), yet modifiers that facilitate the survival and progression of nascent tumor cells are not well defined. Using genetic and pharmacological approaches in mouse CRC and human CRC xenograft models, we show that incipient intestinal tumor cells activate CDC42, an APC-interacting small GTPase, as a crucial step in malignant progression. In the mouse, Cdc42 ablation attenuated the tumorigenicity of mutant intestinal cells carrying single APC or β-catenin mutations. Similarly, human CRC with relatively higher levels of CDC42 activity were particularly sensitive to CDC42 blockade. Mechanistic studies suggested that Cdc42 may be activated at different levels, including at the level of transcriptional activation of the stem-cell-enriched Rho family exchange factor Arhgef4. Our results suggest that early-stage mutant intestinal epithelial cells must recruit the pleiotropic functions of Cdc42 for malignant progression, suggesting its relevance as a biomarker and therapeutic target for selective CRC intervention. PMID:25113996

  8. Structural and Enzymatic Analysis of Tumor-Targeted Antifolates That Inhibit Glycinamide Ribonucleotide Formyltransferase.

    PubMed

    Deis, Siobhan M; Doshi, Arpit; Hou, Zhanjun; Matherly, Larry H; Gangjee, Aleem; Dann, Charles E

    2016-08-16

    Pemetrexed and methotrexate are antifolates used for cancer chemotherapy and inflammatory diseases. These agents have toxic side effects resulting, in part, from nonspecific cellular transport by the reduced folate carrier (RFC), a ubiquitously expressed facilitative transporter. We previously described 2-amino-4-oxo-6-substituted pyrrolo[2,3-d]pyrimidine antifolates with modifications of the side chain linker and aromatic ring that are poor substrates for RFC but are efficiently transported via folate receptors (FRs) and the proton-coupled folate transporter (PCFT). These targeted antifolates are cytotoxic in vitro toward FR- and PCFT-expressing tumor cells and in vivo with human tumor xenografts in immune-compromised mice, reflecting selective cellular uptake. Antitumor efficacy is due to inhibition of glycinamide ribonucleotide (GAR) formyltransferase (GARFTase) activity in de novo synthesis of purine nucleotides. This study used purified human GARFTase (formyltransferase domain) to assess in vitro inhibition by eight novel thieno- and pyrrolo[2,3-d]pyrimidine antifolates. Seven analogues (AGF23, AGF71, AGF94, AGF117, AGF118, AGF145, and AGF147) inhibited GARFTase with Ki values in the low- to mid-nanomolar concentration range, whereas AGF50 inhibited GARFTase with micromolar potency similar to that of PMX. On the basis of crystal structures of ternary complexes with GARFTase, β-GAR, and the monoglutamyl antifolates, differences in inhibitory potencies correlated well with antifolate binding and the positions of the terminal carboxylates. Our data provide a mechanistic basis for differences in inhibitory potencies between these novel antifolates and a framework for future structure-based drug design. These analogues could be more efficacious than clinically used antifolates, reflecting their selective cellular uptake by FRs and PCFT and potent GARFTase inhibition. PMID:27439469

  9. Crystal structure of the thioesterase domain of human fatty acid synthase inhibited by orlistat

    SciTech Connect

    Pemble,C.; Johnson, L.; Kridel, S.; Lowther, W.

    2007-01-01

    Human fatty acid synthase (FAS) is uniquely expressed at high levels in many tumor types. Pharmacological inhibition of FAS therefore represents an important therapeutic opportunity. The drug Orlistat, which has been approved by the US Food and Drug Administration, inhibits FAS, induces tumor cell-specific apoptosis and inhibits the growth of prostate tumor xenografts. We determined the 2.3-{angstrom}-resolution crystal structure of the thioesterase domain of FAS inhibited by Orlistat. Orlistat was captured in the active sites of two thioesterase molecules as a stable acyl-enzyme intermediate and as the hydrolyzed product. The details of these interactions reveal the molecular basis for inhibition and suggest a mechanism for acyl-chain length discrimination during the FAS catalytic cycle. Our findings provide a foundation for the development of new cancer drugs that target FAS.

  10. A novel recombinant slow-release TNF α-derived peptide effectively inhibits tumor growth and angiogensis.

    PubMed

    Ma, Yi; Zhao, Shaojun; Shen, Shutao; Fang, Shixiong; Ye, Zulu; Shi, Zhi; Hong, An

    2015-01-01

    RMP16, a recombinant TNF α-derived polypeptide comprising a specific human serum albumin (HSA)-binding 7-mer peptide identified by phage display screening (WQRPSSW), a cleavage peptide for Factor Xa (IEGR), and a 20-amino acid bioactive peptide P16 (TNF α segment including amino acid residues 75-94), was prepared by gene-engineering technology. RMP16 showed prolonged half-life, 13.11 hours in mice (half-lives of P16 and TNF α are 5.77 and 29.0 minutes, respectively), and obviously higher receptor selectivity for TNFRI than TNF α. RMP16 had significant inhibition effects for multiple tumor cells, especially prostate cancer Du145 cells, and human vascular endothelial cells but not for human mammary non-tumorigenic epithelial cells. RMP16 can more effectively induce apoptosis and inhibit proliferation for DU145 cells than P16 and TNF α via the caspase-dependent apoptosis pathway and G0/G1 cell cycle arrest. In nude mice with transplanted tumor of DU145 cells, RMP16 significantly induced apoptosis and necrosis of tumor tissues but causing less side effects, and tumor inhibitory rate reached nearly 80%, furthermore, RMP16 can potently inhibit tumor angiogenesis and neovascularization. These findings suggest that RMP16 may represent a promising long-lasting antitumor therapeutic peptide with less TNF α-induced toxicity. PMID:26337231

  11. A novel recombinant slow-release TNF α-derived peptide effectively inhibits tumor growth and angiogensis

    PubMed Central

    Ma, Yi; Zhao, Shaojun; Shen, Shutao; Fang, Shixiong; Ye, Zulu; Shi, Zhi; Hong, An

    2015-01-01

    RMP16, a recombinant TNF α-derived polypeptide comprising a specific human serum albumin (HSA)-binding 7-mer peptide identified by phage display screening (WQRPSSW), a cleavage peptide for Factor Xa (IEGR), and a 20-amino acid bioactive peptide P16 (TNF α segment including amino acid residues 75–94), was prepared by gene-engineering technology. RMP16 showed prolonged half-life, 13.11 hours in mice (half-lives of P16 and TNF α are 5.77 and 29.0 minutes, respectively), and obviously higher receptor selectivity for TNFRI than TNF α. RMP16 had significant inhibition effects for multiple tumor cells, especially prostate cancer Du145 cells, and human vascular endothelial cells but not for human mammary non-tumorigenic epithelial cells. RMP16 can more effectively induce apoptosis and inhibit proliferation for DU145 cells than P16 and TNF α via the caspase-dependent apoptosis pathway and G0/G1 cell cycle arrest. In nude mice with transplanted tumor of DU145 cells, RMP16 significantly induced apoptosis and necrosis of tumor tissues but causing less side effects, and tumor inhibitory rate reached nearly 80%, furthermore, RMP16 can potently inhibit tumor angiogenesis and neovascularization. These findings suggest that RMP16 may represent a promising long-lasting antitumor therapeutic peptide with less TNF α-induced toxicity. PMID:26337231

  12. Retinoic acid inhibits angiogenesis and tumor growth of thyroid cancer cells.

    PubMed

    Hoffmann, Sebastian; Rockenstein, Andreas; Ramaswamy, Anette; Celik, Ilhan; Wunderlich, Anette; Lingelbach, Susanne; Hofbauer, Lorenz C; Zielke, Andreas

    2007-01-29

    The anti-proliferative effect of retinoic acid (RA) has been documented for various tumors. Some 40% of patients with advanced and poorly differentiated thyroid cancer have been shown to respond to RA with increased uptake of radioiodine. It has been suggested that these effects may be caused by redifferentiation. Presently, little is known about the effects of RA on tumor angiogenesis, a prerequisite for growth and metastatic spread. The aim of the current study was to determine, whether tumor-induced angiogenesis of thyroid cancer is affected by RA. In vitro, the effect of 0.1/10 microM 13-cis RA on tumor cell number (MTT assay) and secretion of VEGF (ELISA) was analyzed in three thyroid cancer cell lines (FTC 236, C634 and XTC), as well as in endothelial cells (HUVEC) over several passages. In vivo, tumor growth, VEGF-expression and microvessel density (VSD) of RA treated thyroid cancer cells after xenotransplantation to nude mice was evaluated by morphometric analysis. In vitro, thyroid cancer cell lines responded to RA with reduced proliferation, ranging from 26 to 34% after 2 weeks of treatment and with up to 80% reduced secretion of VEGF. In vivo, tumor volumes of animals receiving RA were reduced by 33% (FTC 236), 27% (C643) and 6% (XTC), respectively. VSD of experimental tumors was diminished in the FTC 236 (25%) and the C643 cell line (15%), and almost unchanged in XTC tumors (7%). In vivo, VEGF-expression and apoptosis were not significantly affected by RA. In vitro, proliferation of HUVEC was inhibited by conditioned medium of C643 cells pretreated with RA (0.1/10 microM), as well as by administration of RA (0.1/10 microM). This study confirms thyroid tumor cell growth to be inhibited by RA. It demonstrates a decrease of in vitro VEGF accumulation and reduction of VSD in experimental undifferentiated thyroid carcinoma, suggesting that reduced angiogenesis may be an important mechanism responsible for the therapeutic effect of RA in thyroid cancer

  13. Peptide inhibition of human cytomegalovirus infection

    PubMed Central

    2011-01-01

    Background Human cytomegalovirus (HCMV) is the most prevalent congenital viral infection in the United States and Europe causing significant morbidity and mortality to both mother and child. HCMV is also an opportunistic pathogen in immunocompromised individuals, including human immunodeficiency virus (HIV)- infected patients with AIDS, and solid organ and allogeneic stem cell transplantation recipients. Current treatments for HCMV-associated diseases are insufficient due to the emergence of drug-induced resistance and cytotoxicity, necessitating novel approaches to limit HCMV infection. The aim of this study was to develop therapeutic peptides targeting glycoprotein B (gB), a major glycoprotein of HCMV that is highly conserved across the Herpesviridae family, that specifically inhibit fusion of the viral envelope with the host cell membrane preventing HCMV entry and infection. Results Using the Wimley-White Interfacial Hydrophobicity Scale (WWIHS), several regions within gB were identified that display a high potential to interact with lipid bilayers of cell membranes and hydrophobic surfaces within proteins. The ability of synthetic peptides analogous to WWIHS-positive sequences of HCMV gB to inhibit viral infectivity was evaluated. Human foreskin fibroblasts (HFF) were infected with the Towne-GFP strain of HCMV (0.5 MOI), preincubated with peptides at a range of concentrations (78 nm to 100 μM), and GFP-positive cells were visualized 48 hours post-infection by fluorescence microscopy and analyzed quantitatively by flow cytometry. Peptides that inhibited HCMV infection demonstrated different inhibitory concentration curves indicating that each peptide possesses distinct biophysical properties. Peptide 174-200 showed 80% inhibition of viral infection at a concentration of 100 μM, and 51% and 62% inhibition at concentrations of 5 μM and 2.5 μM, respectively. Peptide 233-263 inhibited infection by 97% and 92% at concentrations of 100 μM and 50 μM, respectively

  14. Inhibition of lung tumor colonization and cell migration with the disintegrin crotatroxin 2 isolated from the venom of Crotalus atrox.

    PubMed

    Galán, Jacob A; Sánchez, Elda E; Rodríguez-Acosta, Alexis; Soto, Julio G; Bashir, Sajid; McLane, Mary Ann; Paquette-Straub, Carrie; Pérez, John C

    2008-06-01

    Disintegrins are low molecular weight proteins (4-15 kDa) with an RGD binding region at their binding loop. Disintegrin and disintegrin-like proteins are found in the venom of four families of snakes: Atractaspididae, Elapidae, Viperidae, and Colubridae. This report describes the biological activity of a disintegrin, crotatroxin 2, isolated by a three-step chromatography procedure from the venom of the Western diamondback rattlesnake (Crotalus atrox). The intact molecular mass for crotatroxin 2 was 7.384 kDa and 71 amino acids. Crotatroxin 2 inhibited human whole blood platelet aggregation with an IC(50) of 17.5 nM, inhibited cell (66.3p) migration by 63%, and inhibited experimental lung tumor colonization in BALB/c mice at 1000 microg/kg. Our data suggest that while crotatroxin 2 inhibits platelet aggregation, cancer cell migration, and lung tumor colonization, it is done via different integrins. PMID:18387648

  15. Inhibition of breast tumor growth and angiogenesis by a medicinal herb: Ocimum sanctum

    PubMed Central

    Nangia-Makker, Pratima; Tait, Larry; Hogan, Victor; Shekhar, Malathy P.V.; Funasaka, Tatsuyoshi; Raz, Avraham

    2013-01-01

    Ocimum sanctum (OS) is a traditionally used medicinal herb, which shows anti-oxidant, anti-carcinogenic, radio-protective and free radical scavenging properties. So far no detailed studies have been reported on its effects on human cancers. Thus, we analyzed its effects on human breast cancer utilizing in vitro and in vivo methodologies. Aqueous extracts were prepared from the mature leaves of Ocimum sanctum cultivated devoid of pesticides. Tumor progression and angiogenesis related processes like chemotaxis, proliferation, apoptosis, 3-dimensional growth and morphogenesis, angiogenesis, and tumor growth were studied in the presence or absence of the extract and in some experiments a comparison was made with purified commercially available eugenol, apigenin and ursolic acid. Aqueous OS leaf extract inhibits proliferation, migration, anchorage independent growth, three dimensional growth and morphogenesis, and induction of COX-2 protein in breast cancer cells. A comparative analysis with eugenol, apigenin and ursolic acid showed that the inhibitory effects on chemotaxis and three dimensional morphogenesis of breast cancer cells were specific to OS extract. In addition, OS extracts also reduced tumor size and neoangiogenesis in a MCF10 DCIS.com xenograft model of human DCIS. This is the first detailed report showing that OS leaf extract may be of value as a breast cancer preventive and therapeutic agent and might be considered as additional additive in the arsenal of components aiming at combating breast cancer progression and metastasis. PMID:17437270

  16. Aptamers Binding to c-Met Inhibiting Tumor Cell Migration

    PubMed Central

    Piater, Birgit; Doerner, Achim; Guenther, Ralf; Kolmar, Harald; Hock, Bjoern

    2015-01-01

    The human receptor tyrosine kinase c-Met plays an important role in the control of critical cellular processes. Since c-Met is frequently over expressed or deregulated in human malignancies, blocking its activation is of special interest for therapy. In normal conditions, the c-Met receptor is activated by its bivalent ligand hepatocyte growth factor (HGF). Also bivalent antibodies can activate the receptor by cross linking, limiting therapeutic applications. We report the generation of the RNA aptamer CLN64 containing 2’-fluoro pyrimidine modifications by systematic evolution of ligands by exponential enrichment (SELEX). CLN64 and a previously described single-stranded DNA (ssDNA) aptamer CLN3 exhibited high specificities and affinities to recombinant and cellular expressed c-Met. Both aptamers effectively inhibited HGF-dependent c-Met activation, signaling and cell migration. We showed that these aptamers did not induce c-Met activation, revealing an advantage over bivalent therapeutic molecules. Both aptamers were shown to bind overlapping epitopes but only CLN3 competed with HGF binding to cMet. In addition to their therapeutic and diagnostic potential, CLN3 and CLN64 aptamers exhibit valuable tools to further understand the structural and functional basis for c-Met activation or inhibition by synthetic ligands and their interplay with HGF binding. PMID:26658271

  17. Targeted BMI1 inhibition impairs tumor growth in lung adenocarcinomas with low CEBPα expression.

    PubMed

    Yong, Kol Jia; Basseres, Daniela S; Welner, Robert S; Zhang, Wen Cai; Yang, Henry; Yan, Benedict; Alberich-Jorda, Meritxell; Zhang, Junyan; de Figueiredo-Pontes, Lorena Lobo; Battelli, Chiara; Hetherington, Christopher J; Ye, Min; Zhang, Hong; Maroni, Giorgia; O'Brien, Karen; Magli, Maria Cristina; Borczuk, Alain C; Varticovski, Lyuba; Kocher, Olivier; Zhang, Pu; Moon, Young-Choon; Sydorenko, Nadiya; Cao, Liangxian; Davis, Thomas W; Thakkar, Bhavin M; Soo, Ross A; Iwama, Atsushi; Lim, Bing; Halmos, Balazs; Neuberg, Donna; Tenen, Daniel G; Levantini, Elena

    2016-08-01

    Lung cancer is the most common cause of cancer deaths. The expression of the transcription factor C/EBPα (CCAAT/enhancer binding protein α) is frequently lost in non-small cell lung cancer, but the mechanisms by which C/EBPα suppresses tumor formation are not fully understood. In addition, no pharmacological therapy is available to specifically target C/EBPα expression. We discovered a subset of pulmonary adenocarcinoma patients in whom negative/low C/EBPα expression and positive expression of the oncogenic protein BMI1 (B lymphoma Mo-MLV insertion region 1 homolog) have prognostic value. We also generated a lung-specific mouse model of C/EBPα deletion that develops lung adenocarcinomas, which are prevented by Bmi1 haploinsufficiency. BMI1 activity is required for both tumor initiation and maintenance in the C/EBPα-null background, and pharmacological inhibition of BMI1 exhibits antitumor effects in both murine and human adenocarcinoma lines. Overall, we show that C/EBPα is a tumor suppressor in lung cancer and that BMI1 is required for the oncogenic process downstream of C/EBPα loss. Therefore, anti-BMI1 pharmacological inhibition may offer a therapeutic benefit for lung cancer patients with low expression of C/EBPα and high BMI1. PMID:27488898

  18. GSK-3 inhibition overcomes chemoresistance in human breast cancer.

    PubMed

    Ugolkov, Andrey; Gaisina, Irina; Zhang, Jin-San; Billadeau, Daniel D; White, Kevin; Kozikowski, Alan; Jain, Sarika; Cristofanilli, Massimo; Giles, Francis; O'Halloran, Thomas; Cryns, Vincent L; Mazar, Andrew P

    2016-10-01

    Glycogen Synthase Kinase-3β (GSK-3β), a serine/threonine protein kinase, is an emerging therapeutic target in the treatment of human breast cancer. In this study, we demonstrate that the pharmacological inhibition of GSK-3 by two novel small molecule GSK-3 inhibitors, 9-ING-41 and 9-ING-87, reduced the viability of breast cancer cells but had little effect on non-tumorigenic cell growth. Moreover, treatment with 9-ING-41 enhanced the antitumor effect of irinotecan (CPT-11) against breast cancer cells in vitro. We next established two patient-derived xenograft tumor models (BC-1 and BC-2) from metastatic pleural effusions obtained from patients with progressive, chemorefractory breast cancer and demonstrated that 9-ING-41 also potentiated the effect of the chemotherapeutic drug CPT-11 in vivo, leading to regression of established BC-1 and BC-2 tumors in mice. Our results suggest that the inhibition of GSK-3 is a promising therapeutic approach to overcome chemoresistance in human breast cancer, and identify the GSK-3 inhibitor 9-ING-41 as a candidate targeted agent for metastatic breast cancer therapy. PMID:27424289

  19. Synergistic action of tiazofurin with hypoxanthine and allopurinol in human neuroectodermal tumor cell lines.

    PubMed

    Szekeres, T; Schuchter, K; Chiba, P; Ressmann, G; Lhotka, C; Gharehbaghi, K; Szalay, S M; Pillwein, K

    1993-12-01

    The activity of IMP dehydrogenase (EC 1.2.1.14), the key enzyme of de novo guanylate biosynthesis, was shown to be increased in tumor cells. Tiazofurin (TR), a potent and specific inhibitor of this enzyme, proved to be effective in the treatment of refractory granulocytic leukemia in blast crisis. We examined the effects of tiazofurin as a single agent and in combination with hypoxanthine and allopurinol in six different neuroectodermal tumor cell lines, the STA-BT-3 and 146-18 human glioblastoma cell lines, the SK-N-SH, LA-N-1 and LA-N-5 human neuroblastoma cell lines, and the STA-ET-1 Ewing tumor cell line. Tiazofurin inhibited tumor cell growth with IC50 values between 2.2 microM (LA-N-1 cell line) and 550 microM (LA-N-5 cells) and caused a significant decrease of intracellular GTP pools (GTP concentrations decreased to 39-79% of control). Incorporation of [8-14C]guanine into GTP pools was determined as a measure of guanylate salvage activity; incubation with 100 microM hypoxanthine caused a 62-96% inhibition of the salvage pathway. Incubation with tiazofurin (100 microM) and hypoxanthine (100 microM) synergistically inhibited tumor cell growth, and the addition of allopurinol (100 microM) strengthened these effects. Therefore, this drug combination, inhibiting guanylate de novo and salvage pathways, may prove useful in the treatment of human neuroectodermal tumors. PMID:7903533

  20. Tumor cell responses to inhibition of thymidylate synthase

    SciTech Connect

    Keyomarsi, K.

    1989-01-01

    The cellular, biochemical and molecular events that occur in tumor cells treated with inhibitors of thymidylate synthase (TS) were studied. 5-Fluorouracil (5-FUra) and fluorodeoxyuridine (FdUrd) are more growth inhibitory to mouse and human tumor cells when grown in medium containing folinate. L1210 cells exposed to folinate and noncytotoxic concentrations of 5-FUra or FdUrd, resulted in a 98% to 99.98% cell kill. Exposure of L1210 cells to folinate resulted in expansion of intracellular pools of 5,10-methylenetetrahydrofolate, delayed the reappearance of catalytically active TS following FdUrd exposure, and stabilized inactive TS complexes over the same concentration range that augmented the cytotoxic effect of FdUrd and 5-FUra. In intact L1210 cells, fluorodeoxyuridylate (FdUMP) behaved as an inhibitor whose complexes with TS dissociate with a biologically significant rate. However, these complexes become functionally irreversible in cells incubated with high levels of folinate. CB 3717 eliminated TS activity in L1210 cells, yet the inactive enzyme retained the ability to bind ({sup 3}H)-FdUMP covalently, suggesting that the binding of one subunit of TS inactivates the catalytic activity of both subunits.

  1. N -Methyl- N -nitrosourea-induced Renal Tumors in Rats: Immunohistochemical Comparison to Human Wilms Tumors

    PubMed Central

    Yoshizawa, Katsuhiko; Kinoshita, Yuichi; Emoto, Yuko; Kimura, Ayako; Uehara, Norihisa; Yuri, Takashi; Shikata, Nobuaki; Tsubura, Airo

    2013-01-01

    N-Methyl-N-nitrosourea (MNU)-induced renal tumors in rats and Wilms tumors in humans were compared. Renal mesenchymal tumors (RMTs) and nephroblastomas (blastemal and epithelial components) in female Lewis rats treated with a single intraperitoneal injection of 50 mg/kg MNU at birth and Wilms tumors (blastemal, epithelial and mesenchymal components) in humans were analyzed for the expression of pancytokeratin (CK), vimentin, p63, α-smooth muscle actin (SMA), desmin, S-100, CD57, CD117/c-kit, Wilms tumor 1 protein (WT1) and β-catenin. The mesenchymal components of rat RMTs and human Wilms tumors expressed vimentin, SMA and β-catenin. The blastemal components of rat nephroblastomas and human Wilms tumors expressed vimentin, CD117/c-kit and β-catenin. The epithelial components of rat nephroblastomas and human Wilms tumors expressed vimentin and β-catenin. WT1 was expressed in different cellular components of rat tumors as compared with human Wilms tumors; the expression was seen in mesenchymal tumors and blastemal components of nephroblastomas in rats and epithelial components in human Wilms tumors. CK, p63 and CD57 were not expressed in rat RMTs or nephroblastomas, while CK and WT1 were expressed in epithelial components and CD57 was expressed in blastemal and epithelial components of human Wilms tumors. Rat and human tumors were universally negative for the expression of desmin and S-100. The immunohistochemical characteristics of rat renal tumors and human Wilms tumors may provide valuable information on the differences in renal oncogenesis and biology between the two species. PMID:23914056

  2. Carbon Monoxide Expedites Metabolic Exhaustion to Inhibit Tumor Growth

    PubMed Central

    Wegiel, Barbara; Gallo, David; Csizmadia, Eva; Harris, Clair; Belcher, John; Vercellotti, Gregory M.; Penacho, Nuno; Seth, Pankaj; Sukhatme, Vikas; Ahmed, Asif; Pandolfi, Pier Paolo; Helczynski, Leszek; Bjartell, Anders; Persson, Jenny Liao; Otterbein, Leo E

    2013-01-01

    One classical feature of cancer cells is their metabolic acquisition of a highly glycolytic phenotype. Carbon monoxide (CO), one of the products of the cytoprotective molecule heme oxygenase-1 (HO-1) in cancer cells, has been implicated in carcinogenesis and therapeutic resistance. However, the functional contributions of CO and HO-1 to these processes are poorly defined. In human prostate cancers, we found that HO-1 was nuclear localized in malignant cells, with low enzymatic activity in moderately differentiated tumors correlating with relatively worse clinical outcomes. Exposure to CO sensitized prostate cancer cells but not normal cells to chemotherapy, with growth arrest and apoptosis induced in vivo in part through mitotic catastrophe. CO targeted mitochondria activity in cancer cells as evidenced by higher oxygen consumption, free radical generation and mitochondrial collapse. Collectively, our findings indicated that CO transiently induces an anti-Warburg effect by rapidly fueling cancer cell bioenergetics, ultimately resulting in metabolic exhaustion. PMID:24121491

  3. Vitamin D binding protein-macrophage activating factor (DBP-maf) inhibits angiogenesis and tumor growth in mice.

    PubMed

    Kisker, Oliver; Onizuka, Shinya; Becker, Christian M; Fannon, Michael; Flynn, Evelyn; D'Amato, Robert; Zetter, Bruce; Folkman, Judah; Ray, Rahul; Swamy, Narasimha; Pirie-Shepherd, Steven

    2003-01-01

    We have isolated a selectively deglycosylated form of vitamin D binding protein (DBP-maf) generated from systemically available DBP by a human pancreatic cancer cell line. DBP-maf is antiproliferative for endothelial cells and antiangiogenic in the chorioallantoic membrane assay. DBP-maf administered daily was able to potently inhibit the growth of human pancreatic cancer in immune compromised mice (T/C=0.09). At higher doses, DBP-maf caused tumor regression. Histological examination revealed that treated tumors had a higher number of infiltrating macrophages as well as reduced microvessel density, and increased levels of apoptosis relative to untreated tumors. Taken together, these data suggest that DBP-maf is an antiangiogenic molecule that can act directly on endothelium as well as stimulate macrophages to attack both the endothelial and tumor cell compartment of a growing malignancy. PMID:12659668

  4. Vitamin D Binding Protein-Macrophage Activating Factor (DBP-maf) Inhibits Angiogenesis and Tumor Growth in Mice1

    PubMed Central

    Kisker, Oliver; Onizuka, Shinya; Becker, Christian M; Fannon, Michael; Flynn, Evelyn; D'Amato, Robert; Zetter, Bruce; Folkman, Judah; Ray, Rahul; Swamy, Narasimha; Pirie-Shepherd, Steven

    2003-01-01

    Abstract We have isolated a selectively deglycosylated form of vitamin D binding protein (DBP-maf) generated from systemically available DBP by a human pancreatic cancer cell line. DBP-maf is antiproliferative for endothelial cells and antiangiogenic in the chorioallantoic membrane assay. DBP-maf administered daily was able to potently inhibit the growth of human pancreatic cancer in immune compromised mice (T/C=0.09). At higher doses, DBP-maf caused tumor regression. Histological examination revealed that treated tumors had a higher number of infiltrating macrophages as well as reduced microvessel density, and increased levels of apoptosis relative to untreated tumors. Taken together, these data suggest that DBP-maf is an antiangiogenic molecule that can act directly on endothelium as well as stimulate macrophages to attack both the endothelial and tumor cell compartment of a growing malignancy. PMID:12659668

  5. Lactate Activates HIF-1 in Oxidative but Not in Warburg-Phenotype Human Tumor Cells

    PubMed Central

    De Saedeleer, Christophe J.; Copetti, Tamara; Porporato, Paolo E.; Verrax, Julien

    2012-01-01

    Cancer can be envisioned as a metabolic disease driven by pressure selection and intercellular cooperativeness. Together with anaerobic glycolysis, the Warburg effect, formally corresponding to uncoupling glycolysis from oxidative phosphorylation, directly participates in cancer aggressiveness, supporting both tumor progression and dissemination. The transcription factor hypoxia-inducible factor-1 (HIF-1) is a key contributor to glycolysis. It stimulates the expression of glycolytic transporters and enzymes supporting high rate of glycolysis. In this study, we addressed the reverse possibility of a metabolic control of HIF-1 in tumor cells. We report that lactate, the end-product of glycolysis, inhibits prolylhydroxylase 2 activity and activates HIF-1 in normoxic oxidative tumor cells but not in Warburg-phenotype tumor cells which also expressed lower basal levels of HIF-1α. These data were confirmed using genotypically matched oxidative and mitochondria-depleted glycolytic tumor cells as well as several different wild-type human tumor cell lines of either metabolic phenotype. Lactate activates HIF-1 and triggers tumor angiogenesis and tumor growth in vivo, an activity that we found to be under the specific upstream control of the lactate transporter monocarboxylate transporter 1 (MCT1) expressed in tumor cells. Because MCT1 also gates lactate-fueled tumor cell respiration and mediates pro-angiogenic lactate signaling in endothelial cells, MCT1 inhibition is confirmed as an attractive anticancer strategy in which a single drug may target multiple tumor-promoting pathways. PMID:23082126

  6. Syzygium campanulatum korth methanolic extract inhibits angiogenesis and tumor growth in nude mice

    PubMed Central

    2013-01-01

    Background Syzygium campanulatum Korth (Myrtaceae) is an evergreen shrub rich in phenolics, flavonoid antioxidants, and betulinic acid. This study sought to investigate antiangiogenic and anti-colon cancer effects of S.C. standardized methanolic extract. Methods Betulinic acid was isolated from methanolic extract by crystallization and chromatography techniques. S.C. methanolic extract was analyzed by UV-Vis spectrophotometry, FTIR, LC-MS, and HPLC. Antiangiogenic effect was studied on rat aortic rings, matrigel tube formation, cell proliferation and migration, and expression of vascular endothelial growth factor (VEGF). Antitumor effect was studied using a subcutaneous tumor model of HCT 116 colorectal carcinoma cells established in nude mice. Results Analysis by HPLC, LC-MS and FTIR confirm presence of betulinic acid in S.C. methanolic extract. Quantitative analysis by HPLC indicates presence of betulinic acid in S.C. extract at 5.42 ± 0.09% (w/w). Antiangiogenesis study showed potent inhibition of microvessels outgrowth in rat aortic rings, and studies on normal and cancer cells did not show any significant cytotoxic effect. Antiangiogenic effect was further confirmed by inhibition of tube formation on matrigel matrix that involves human endothelial cells (IC50 = 17.6 ± 2.9 μg/ml). S.C. extract also inhibited migration of endothelial cells and suppressed expression of VEGF. In vivo antiangiogenic study showed inhibition of new blood vessels in chicken embryo chorioallantoic membrane (CAM), and in vivo antitumor study showed significant inhibition of tumor growth due to reduction of intratumor blood vessels and induction of cell death. Conclusion Collectively, our results indicate S. campanulatum as antiangiogenic and antitumor candidate, and a new source of betulinic acid. PMID:23842450

  7. PPARα inhibition modulates multiple reprogrammed metabolic pathways in kidney cancer and attenuates tumor growth

    PubMed Central

    Abu Aboud, Omran; Donohoe, Dallas; Bultman, Scott; Fitch, Mark; Riiff, Tim; Hellerstein, Marc

    2015-01-01

    Kidney cancer [renal cell carcinoma (RCC)] is the sixth-most-common cancer in the United States, and its incidence is increasing. The current progression-free survival for patients with advanced RCC rarely extends beyond 1–2 yr due to the development of therapeutic resistance. We previously identified peroxisome proliferator-activating receptor-α (PPARα) as a potential therapeutic target for this disease and showed that a specific PPARα antagonist, GW6471, induced apoptosis and cell cycle arrest at G0/G1 in RCC cell lines associated with attenuation of cell cycle regulatory proteins. We now extend that work and show that PPARα inhibition attenuates components of RCC metabolic reprogramming, capitalizing on the Warburg effect. The specific PPARα inhibitor GW6471, as well as a siRNA specific to PPARα, attenuates the enhanced fatty acid oxidation and oxidative phosphorylation associated with glycolysis inhibition, and PPARα antagonism also blocks the enhanced glycolysis that has been observed in RCC cells; this effect did not occur in normal human kidney epithelial cells. Such cell type-specific inhibition of glycolysis corresponds with changes in protein levels of the oncogene c-Myc and has promising clinical implications. Furthermore, we show that treatment with GW6471 results in RCC tumor growth attenuation in a xenograft mouse model, with minimal obvious toxicity, a finding associated with the expected on-target effects on c-Myc. These studies demonstrate that several pivotal cancer-relevant metabolic pathways are inhibited by PPARα antagonism. Our data support the concept that targeting PPARα, with or without concurrent inhibition of glycolysis, is a potential novel and effective therapeutic approach for RCC that targets metabolic reprogramming in this tumor. PMID:25810260

  8. Mesenchymal stromal cells inhibit murine syngeneic anti-tumor immune responses by attenuating inflammation and reorganizing the tumor microenvironment.

    PubMed

    Modiano, Jaime F; Lindborg, Beth A; McElmurry, Ron T; Lewellen, Mitzi; Forster, Colleen L; Zamora, Edward A; Schaack, Jerome; Bellgrau, Donald; O'Brien, Timothy D; Tolar, Jakub

    2015-11-01

    The potential of mesenchymal stromal cells (MSCs) to inhibit anti-tumor immunity is becoming increasingly well recognized, but the precise steps affected by these cells during the development of an anti-tumor immune response remain incompletely understood. Here, we examined how MSCs affect the steps required to mount an effective anti-tumor immune response following administration of adenovirus Fas ligand (Ad-FasL) in the Lewis lung carcinoma (LL3) model. Administration of bone marrow-derived MSCs with LL3 cells accelerated tumor growth significantly. MSCs inhibited the inflammation induced by Ad-FasL in the primary tumors, precluding their rejection; MSCs also reduced the consequent expansion of tumor-specific T cells in the treated hosts. When immune T cells were transferred to adoptive recipients, MSCs impaired, but did not completely abrogate the ability of these T cells to promote elimination of secondary tumors. This impairment was associated with a modest reduction in tumor-infiltrating T cells, with a significant reduction in tumor-infiltrating macrophages, and with a reorganization of the stromal environment. Our data indicate that MSCs in the tumor environment reduce the efficacy of immunotherapy by creating a functional and anatomic barrier that impairs inflammation, T cell priming and expansion, and T cell function-including recruitment of effector cells. PMID:26250807

  9. Rubus idaeus L Inhibits Invasion Potential of Human A549 Lung Cancer Cells by Suppression Epithelial-to-Mesenchymal Transition and Akt Pathway In Vitro and Reduces Tumor Growth In Vivo.

    PubMed

    Chu, Shu-Chen; Hsieh, Yih-Shou; Hsu, Li-Sung; Chen, Kuo-Shuen; Chiang, Chien-Cheng; Chen, Pei-Ni

    2014-05-01

    The metastasis of lung cancer is the most prevalent cause of patient death. Various treatment strategies have targeted the prevention of the occurrence of metastasis. The epithelial-mesenchymal transition (EMT) in lung cancer cells is considered a prerequisite to acquire the invasive/migratory phenotype and to subsequently achieve metastasis. However, the effects ofRubus idaeuson cancer invasion and the EMT of the human lung carcinoma remain unclear. In this article, we test the hypothesis thatR idaeusethyl acetate (RIAE) possesses an antimetastatic effect and reverses the EMT potential of human lung A549 cells. We extract the raspberryR idaeuswith methanol (RIME), chloroform (RICE), ethyl acetate (RIAE),n-butanol (RIBE), and water (RIWE). The RIAE treatment obviously inhibits the invasive (P< .001), motility (P< .001), spreading, and migratory potential (P< .001) of highly metastatic human lung cancer A549 cells. The zymography and promoter luciferase analysis reveals that RIAE decreases the proteinase and transcription activities of MMP-2 and u-PA. Molecular analyses show that RIAE increases the E-cadherin level that is mainly localized at the cellular membrane. This result was also verified through confocal analyses. RIAE also induces the upregulation of an epithelial marker, such as α-catenin, and decreases mesenchymal markers, such as snail-1 and N-cadherin, that promote cell invasion and metastasis. RIAE inhibits MMP-2 and u-PA by attenuating the NF-κB and p-Akt expression. The inhibition of RIAE on the growth of A549 cells in vivo was also verified using a cancer cell xenograft nude mice model. Our results show the anti-invasive/antitumor effects of RIAE and associated mechanisms, which suggest that RIAE should be further tested in clinically relevant models to exploit its potential benefits against metastatic lung cancer cells. PMID:24335666

  10. Wilfoside K1N isolated from Cynanchum wilfordii inhibits angiogenesis and tumor cell invasion.

    PubMed

    Kim, Myoung Sook; Baek, Jin Hyen; Park, Jeong Ae; Hwang, Bang Yeon; Kim, Se Eun; Lee, Jung Joon; Kim, Kyu-Won

    2005-06-01

    Wilfoside K1N is a polyoxypregnane glycoside isolated from Cynanchum wilfordii (Asclepiadaceae). Polyoxypregnane glycosides are associated with cellular immunity and anti-tumor activity, and increase the cytotoxicity of many anti-cancer drugs showing multidrug resistant activity on tumor cells. In the present study, we investigated the anti-angiogenic and anti-invasive activities of wilfoside K1N. In in vivo Matrigel plug assay using C57BL/6 mice, wilfoside K1N strongly inhibited basic fibroblast growth factor-induced microvessel formation. Exposure of wilfoside K1N to human umbilical vein endothelial cells (HUVEC) suppressed in vitro tube formation at a concentration not affecting cell viability. Moreover, wilfoside K1N significantly reduced the proliferation of HUVEC and calf pulmonary artery endothelial cells. In addition, wilfoside K1N decreased in vitro invasion of HT1080 human fibrosarcoma cells, and the inhibition might be through down-regulation of activity as well as quantity of matrix metalloproteinase-9. Therefore, our present study suggests that wilfoside K1N may have a potential to have strong anti-angiogenic and anti-invasive activities both in vitro and in vivo. PMID:15870866

  11. Anti-tumor effect of inhibition of IL-6 signaling in mucoepidermoid carcinoma

    PubMed Central

    Mochizuki, Daiki; Adams, April; Warner, Kristy A.; Zhang, Zhaocheng; Pearson, Alexander T.; Misawa, Kiyoshi; McLean, Scott A.; Wolf, Gregory T.; Nör, Jacques E.

    2015-01-01

    Mucoepidermoid carcinoma (MEC) is the most frequent malignant salivary gland cancer. Response to chemoradiotherapy is modest, and therefore radical surgery remains the standard-of-care. Emerging evidence suggests that Interleukin (IL)-6 signaling correlates with the survival of cancer stem cells and resistance to therapy. Here, we investigated whether inhibition of IL-6 receptor (IL-6R) signaling with tocilizumab (humanized anti-human IL-6R antibody) sensitizes MEC to chemotherapy using human mucoepidermoid carcinoma cell lines (UM-HMC) and correspondent xenograft models. In vitro, we observed that tocilizumab inhibited STAT3 phosphorylation but had no measurable effect in MEC cell viability (UM-HMC-1,-3A,-3B). In contrast, the anti-tumor effect of single agent tocilizumab on MEC xenografts was comparable to paclitaxel or cisplatin. Combination of tocilizumab with cisplatin or paclitaxel enhanced the inhibitory effect of chemotherapy on xenograft growth (P < 0.05), time to failure (P < 0.01), decreased vascular endothelial growth factor (VEGF) expression and tumor microvessel density (P < 0.05) without added systemic toxicities. Notably, tocilizumab decreased the fraction of MEC cancer stem cells (ALDHhighCD44high) in vitro, and prevented paclitaxel-induced increase in the fraction of cancer stem cells in vivo (P < 0.05). Collectively, these findings demonstrate that tocilizumab enhances the anti-tumor effect of conventional chemotherapy in preclinical models of mucoepidermoid carcinoma, and suggest that patients might benefit from combination therapy with an inhibitor of IL-6R signaling and chemotherapeutic agent such as paclitaxel. PMID:26287605

  12. Anti-tumor effect of inhibition of IL-6 signaling in mucoepidermoid carcinoma.

    PubMed

    Mochizuki, Daiki; Adams, April; Warner, Kristy A; Zhang, Zhaocheng; Pearson, Alexander T; Misawa, Kiyoshi; McLean, Scott A; Wolf, Gregory T; Nör, Jacques E

    2015-09-01

    Mucoepidermoid carcinoma (MEC) is the most frequent malignant salivary gland cancer. Response to chemoradiotherapy is modest, and therefore radical surgery remains the standard-of-care. Emerging evidence suggests that Interleukin (IL)-6 signaling correlates with the survival of cancer stem cells and resistance to therapy. Here, we investigated whether inhibition of IL-6 receptor (IL-6R) signaling with tocilizumab (humanized anti-human IL-6R antibody) sensitizes MEC to chemotherapy using human mucoepidermoid carcinoma cell lines (UM-HMC) and correspondent xenograft models. In vitro, we observed that tocilizumab inhibited STAT3 phosphorylation but had no measurable effect in MEC cell viability (UM-HMC-1,-3A,-3B). In contrast, the anti-tumor effect of single agent tocilizumab on MEC xenografts was comparable to paclitaxel or cisplatin. Combination of tocilizumab with cisplatin or paclitaxel enhanced the inhibitory effect of chemotherapy on xenograft growth (P < 0.05), time to failure (P < 0.01), decreased vascular endothelial growth factor (VEGF) expression and tumor microvessel density (P < 0.05) without added systemic toxicities. Notably, tocilizumab decreased the fraction of MEC cancer stem cells (ALDH(high)CD44(high)) in vitro, and prevented paclitaxel-induced increase in the fraction of cancer stem cells in vivo (P < 0.05). Collectively, these findings demonstrate that tocilizumab enhances the anti-tumor effect of conventional chemotherapy in preclinical models of mucoepidermoid carcinoma, and suggest that patients might benefit from combination therapy with an inhibitor of IL-6R signaling and chemotherapeutic agent such as paclitaxel. PMID:26287605

  13. Therapeutic inhibition of Jak activity inhibits progression of gastrointestinal tumors in mice.

    PubMed

    Stuart, Emma; Buchert, Michael; Putoczki, Tracy; Thiem, Stefan; Farid, Ryan; Elzer, Joachim; Huszar, Dennis; Waring, Paul M; Phesse, Toby J; Ernst, Matthias

    2014-02-01

    Aberrant activation of the latent transcription factor STAT3 and its downstream targets is a common feature of epithelial-derived human cancers, including those of the gastrointestinal tract. Mouse models of gastrointestinal malignancy implicate Stat3 as a key mediator of inflammatory-driven tumorigenesis, in which its cytokine/gp130/Janus kinase (Jak)-dependent activation provides a functional link through which the microenvironment sustains tumor promotion. Although therapeutic targeting of STAT3 is highly desirable, such molecules are not available for immediate clinical assessment. Here, we investigated whether the small-molecule Jak1/2 inhibitor AZD1480 confers therapeutic benefits in two mouse models of inflammation-associated gastrointestinal cancer, which are strictly dependent of excessive Stat3 activation. We confirm genetically that Cre-mediated, tumor cell-specific reduction of Stat3 expression arrests the growth of intestinal-type gastric tumors in gp130(F/F) mice. We find that systemic administration of AZD1480 readily replicates this effect, which is associated with reduced Stat3 activation and correlates with diminished tumor cell proliferation and increased apoptosis. Likewise, AZD1480 therapy also conferred a cytostatic effect on established tumors in a colitis-associated colon cancer model in wild-type mice. As predicted from our genetic observations in gp130(F/F) mice, the therapeutic effect of AZD1480 remains fully reversible upon cessation of compound administration. Collectively, our results provide the first evidence that pharmacologic targeting of excessively activated wild-type Jak kinases affords therapeutic suppression of inflammation-associated gastrointestinal cancers progression in vivo. PMID:24398427

  14. Novel immunocytokine IL12-SS1 (Fv) inhibits mesothelioma tumor growth in nude mice.

    PubMed

    Kim, Heungnam; Gao, Wei; Ho, Mitchell

    2013-01-01

    Mesothelin is a glycosylphosphatidylinositol-anchored glycoprotein that is highly expressed on the cell surface of malignant mesothelioma. Monoclonal antibodies against mesothelin are being evaluated for the treatment of mesothelioma. Immunocytokines represent a novel class of armed antibodies. To provide an alternative approach to current mesothelin-targeted antibody therapies, we have developed a novel immunocytokine based on interleukin-12 (IL12) and the SS1 Fv specific for mesothelin. IL12 possesses potent anti-tumor activity in a wide variety of solid tumors. The newly-developed recombinant immunocytokine, IL12-SS1 (Fv), was produced in insect cells using a baculovirus-insect cell expression system. The SS1 single-chain Fv was fused to the C terminus of the p35 subunit of IL12 through a short linker (GSADGG). The single-chain IL12-SS1 (Fv) immunocytokine bound native mesothelin proteins on malignant mesothelioma (NCI-H226) and ovarian (OVCAR-3) cells as well as recombinant mesothelin on A431/H9 cells. The immunocytokine retained sufficient bioactivity of IL12 and significantly inhibited human malignant mesothelioma (NCI-H226) grown in the peritoneal cavity of nude mice and showed comparable anti-tumor activity to that of the SS1P immunotoxin. IL12-SS1 (Fv) is the first reported immunocytokine to mesothelin-positive tumors and may be an attractive addition to mesothelin-targeted cancer therapies. PMID:24260587

  15. Alk5 inhibition increases delivery of macromolecular and protein-bound contrast agents to tumors

    PubMed Central

    Daldrup-Link, Heike E.; Mohanty, Suchismita; Ansari, Celina; Lenkov, Olga; Shaw, Aubie; Ito, Ken; Hong, Su Hyun; Hoffmann, Matthias; Pisani, Laura; Boudreau, Nancy; Gambhir, Sanjiv Sam; Coussens, Lisa M.

    2016-01-01

    Limited transendothelial permeability across tumor microvessels represents a significant bottleneck in the development of tumor-specific diagnostic agents and theranostic drugs. Here, we show an approach to increase transendothelial permeability of macromolecular and nanoparticle-based contrast agents via inhibition of the type I TGF-β receptor, activin-like kinase 5 (Alk5), in tumors. Alk5 inhibition significantly increased tumor contrast agent delivery and enhancement on imaging studies, while healthy organs remained relatively unaffected. Imaging data correlated with significantly decreased tumor interstitial fluid pressure, while tumor vascular density remained unchanged. This immediately clinically translatable concept involving Alk5 inhibitor pretreatment prior to an imaging study could be leveraged for improved tumor delivery of macromolecular and nanoparticle-based imaging probes and, thereby, facilitate development of more sensitive imaging tests for cancer diagnosis, enhanced tumor characterization, and personalized, image-guided therapies. PMID:27182558

  16. Bromodichloromethane inhibits human placental trophoblast differentiation.

    PubMed

    Chen, Jiangang; Thirkill, Twanda L; Lohstroh, Peter N; Bielmeier, Susan R; Narotsky, Michael G; Best, Deborah S; Harrison, Randy A; Natarajan, Kala; Pegram, Rex A; Overstreet, James W; Lasley, Bill L; Douglas, Gordon C

    2004-03-01

    Epidemiological data suggest an association between exposures to bromodichloromethane (BDCM), a trihalomethane found in drinking water as a result of drinking water disinfection, and an increased risk of spontaneous abortion. We previously hypothesized that BDCM targets the placenta and showed that the secretion of chorionic gonadotrophin (CG) was reduced in primary cultures of human term syncytiotrophoblasts exposed to BDCM. In the present study we extend this observation by evaluating the effects of BDCM on the morphological differentiation of mononucleated cytotrophoblast cells to multinucleated syncytiotrophoblast-like colonies. Addition of BDCM to cytotrophoblast cultures inhibited the subsequent formation of multinucleated colonies in a dose-dependent manner, as determined by immunocytochemical staining for desmosomes and nuclei. The effect was seen at BDCM concentrations between 0.02 and 2 mM and was confirmed by quantitative image analysis. Secretion of bioactive and immunoreactive chorionic gonadotropin was also significantly inhibited in a dose-dependent manner under these culture conditions, and cellular levels of CG were also reduced. Trophoblast viability was not compromised by exposure to BDCM. We conclude that BDCM disrupts syncytiotrophoblast formation and inhibits CG secretion in vitro. Although other tissue targets are not ruled out, these data substantiate the idea that BDCM targets the placenta and could have implications for understanding the adverse pregnancy outcomes associated with BDCM exposure in humans. PMID:14691210

  17. 3-β-Εrythrodiol isolated from Conyza canadensis inhibits MKN‑45 human gastric cancer cell proliferation by inducing apoptosis, cell cycle arrest, DNA fragmentation, ROS generation and reduces tumor weight and volume in mouse xenograft model.

    PubMed

    Liu, Kai; Qin, Yue-Hong; Yu, Jian-Yong; Ma, Heng; Song, Xi-Lin

    2016-04-01

    The objective of the present study was to investigate the in vitro and in vivo anticancer and apoptotic effects of 3-β-erythrodiol, a plant-derived triterpene against MKN-45 human gastric cancer cells. In addition, effects on cellular morphology, cell cycle phase distribution, DNA fragmentation, and ROS generation were also elucidated in the current research work. Cytotoxic activity of 3-β-erythrodiol was demonstrated by MTT cell viability and LDH assay. Cellular morphological study was carried out using phase contrast, fluorescence and scanning electron microscopy. Cell cycle analysis was evaluated by flow cytometry and gel electrophoresis was used to evaluate DNA fragmentation pattern. The results of the present study revealed that 3-β-erythrodiol induced dose-dependent as well as time-dependent anticancer effects in MKN-45 gastric cancer cells. Cellular morphological changes in MKN-45 cells as indicated by fluorescence and scanning electron microscopy were induced by 3-β-erythrodiol. This triterpene induced both early and late apoptotic features in these cancer cells. 3-β-Erythrodiol treatment led to sub-G1 cell cycle arrest with a corresponding decrease in S-phase cells and an increase in G2/M phase cells. DNA fragments were evident in gel electrophoresis experiment following 3-β-erythrodiol treatment. It was observed that 0.50 and 1.0 µg/g 3-β-erythrodiol injection reduced the tumor weight from 1.4 g in PBS-treated group (control) to 0.61 and 0.22 g, respectively. Similarly, 0.50 and 1.0 µg/g 3-β-erythrodiol injection reduced the tumor volume from 1.5 cm3 in PBS-treated group (control) to 0.91 and 0.31 cm3, respectively. The present investigation indicates that 3-β-erythrodiol exerts anti-proliferative effects in human gastric cancer by inducing early and late apoptosis, cell cycle arrest, and ROS generation. It also decreased the tumor volume and tumor weight in male Balb/c nude mice. PMID:26846256

  18. Dominant-negative inhibition of the Axl receptor tyrosine kinase suppresses brain tumor cell growth and invasion and prolongs survival

    PubMed Central

    Vajkoczy, Peter; Knyazev, Pjotr; Kunkel, Andrea; Capelle, Hans-Holger; Behrndt, Sandra; von Tengg-Kobligk, Hendrik; Kiessling, Fabian; Eichelsbacher, Uta; Essig, Marco; Read, Tracy-Ann; Erber, Ralf; Ullrich, Axel

    2006-01-01

    Malignant gliomas remain incurable brain tumors because of their diffuse-invasive growth. So far, the genetic and molecular events underlying gliomagenesis are poorly understood. In this study, we have identified the receptor tyrosine kinase Axl as a mediator of glioma growth and invasion. We demonstrate that Axl and its ligand Gas6 are overexpressed in human glioma cell lines and that Axl is activated under baseline conditions. Furthermore, Axl is expressed at high levels in human malignant glioma. Inhibition of Axl signaling by overexpression of a dominant-negative receptor mutant (AXL-DN) suppressed experimental gliomagenesis (growth inhibition >85%, P < 0.05) and resulted in long-term survival of mice after intracerebral glioma cell implantation when compared with Axl wild-type (AXL-WT) transfected tumor cells (survival times: AXL-WT, 10 days; AXL-DN, >72 days). A detailed analysis of the distinct hallmarks of glioma pathology, such as cell proliferation, migration, and invasion and tumor angiogenesis, revealed that inhibition of Axl signaling interfered with cell proliferation (inhibition 30% versus AXL-WT), glioma cell migration (inhibition 90% versus mock and AXL-WT, P < 0.05), and invasion (inhibition 62% and 79% versus mock and AXL-WT, respectively; P < 0.05). This study describes the identification, functional manipulation, in vitro and in vivo validation, and preclinical therapeutic inhibition of a target receptor tyrosine kinase mediating glioma growth and invasion. Our findings implicate Axl in gliomagenesis and validate it as a promising target for the development of approaches toward a therapy of these highly aggressive but, as yet, therapy-refractory, tumors. PMID:16585512

  19. Functional atrial natriuretic peptide receptor in human adrenal tumor

    SciTech Connect

    Shionoiri, H.; Hirawa, N.; Takasaki, I.; Ishikawa, Y.; Oda, H.; Minamisawa, K.; Sugimoto, K.; Matsukawa, T.; Ueda, S.; Miyajima, E.

    1989-01-01

    The effects of synthetic human atrial natriuretic peptide (ANP) on the release of catecholamines, aldosterone, or cortisol were observed in human adrenal tumors obtained surgically from patients with pheochromocytoma, primary aldosteronism, or Cushing's syndrome, respectively. Each tumor tissue or adjacent normal cortical tissue was sectioned into slices, which were incubated in medium-199 in the presence or absence of adrenocorticotrophin (ACTH) and ANP. The amounts of epinephrine, norepinephrine, aldosterone, or cortisol released into the medium were measured. Existence of ANP receptors on the adrenal tissues was examined by binding assays, affinity labeling, and immunohistochemistry. Release of catecholamines from pheochromocytoma tissues was inhibited by ANP, and the presence of the ANP receptor on pheochromocytoma was further demonstrated by both binding assays and affinity labeling; Scatchard analysis revealed a single class of binding sites for ANP with a Kd of 1.0 nM and a Bmax of 0.4 pmol/mg of protein and the molecular size was estimated as 140 and a 70 kDa under nonreducing and reducing conditions, respectively. The presence of ANP receptors in pheochromocytoma was demonstrated by immunohistochemistry. ANP inhibited both basal and ACTH-stimulated aldosterone secretion in the slices of normal cortex, and localization of ANP receptors in zona glomerulosa cells was also demonstrated. However, ANP did not inhibit basal and ACTH-stimulated aldosterone and cortisol secretion in both tissue slices from aldosteronoma and Cushing's adenoma. Consistent with these observations, the absence of ANP receptors in adenoma tissues was determined by binding assays, affinity labeling, and immunohistochemistry.

  20. Inhibitions of several antineoplastic drugs on serum sialic Acid levels in mice bearing tumors.

    PubMed

    Lu, Da-Yong; Xu, Jing; Lu, Ting-Ren; Wu, Hong-Ying; Xu, Bin

    2013-03-01

    Six murine tumors, including ascetic tumors HepA, EC, P388 leukemia, S180 and solid tumor S180, and Lewis lung carcinoma, were employed in this work. The free sialic acid concentrations in both blood and ascites were measured in tumor-bearing mice. The results showed that the content of sialic acids in blood was increased in tumor growth and certain tumor types. Higher sialic acid content was observed in ascites than that present in blood. The influence of antineoplastic agents (vincristine, thiotepa, adriamycin, probimane, cisplatin, oxalysine, cortisone, nitrogen mustard, lycobetaine, Ara-C, harringtonine, and cyclophosphamide) on the content of sialic acids in mice blood bearing solid tumors of either S180 or Lewis lung carcinoma was observed. Different inhibitions of antineoplastic drugs on both tumor growth and serum sialic acid levels in mice bearing tumors were found. Among these antineoplastic drugs, probimane, cisplatin, nitrogen mustard, and lycobetaine were able to decrease the serum sialic acid levels in mice bearing tumors. Since these four antineoplastic drugs are all DNA chelating agents, it was proposed that the inhibition of tumor sialic acids by these drugs might be through the DNA template via two ways. Since we have found no effect of antineoplastic drugs on serum sialic acid levels in normal mice, this suggests that the inhibition of antineoplastic drugs on sialic acids is by tumor involvement. PMID:23641340

  1. B7h triggering inhibits the migration of tumor cell lines.

    PubMed

    Dianzani, Chiara; Minelli, Rosalba; Gigliotti, Casimiro Luca; Occhipinti, Sergio; Giovarelli, Mirella; Conti, Laura; Boggio, Elena; Shivakumar, Yogesh; Baldanzi, Gianluca; Malacarne, Valeria; Orilieri, Elisabetta; Cappellano, Giuseppe; Fantozzi, Roberto; Sblattero, Daniele; Yagi, Junji; Rojo, Josè Maria; Chiocchetti, Annalisa; Dianzani, Umberto

    2014-05-15

    Vascular endothelial cells (ECs) and several cancer cells express B7h, which is the ligand of the ICOS T cell costimulatory molecule. We have previously shown that B7h triggering via a soluble form of ICOS (ICOS-Fc) inhibits the adhesion of polymorphonuclear and tumor cell lines to HUVECs; thus, we suggested that ICOS-Fc may act as an anti-inflammatory and antitumor agent. Because cancer cell migration and angiogenesis are crucial for metastasis dissemination, the aim of this work was to evaluate the effect of ICOS-Fc on the migration of cancer cells and ECs. ICOS-Fc specifically inhibited the migration of HUVECs, human dermal lymphatic ECs, and the HT29, HCT116, PC-3, HepG2, JR8, and M14 tumor cell lines expressing high levels of B7h, whereas it was ineffective in the RPMI7932, PCF-2, LM, and BHT-101 cell lines expressing low levels of B7h. Furthermore, ICOS-Fc downmodulated hepatocyte growth factor facilitated the epithelial-to-mesenchymal transition in HepG2 cells. Moreover, ICOS-Fc downmodulated the phosphorylation of focal adhesion kinase and the expression of β-Pix in both HUVECs and tumor cell lines. Finally, treatment with ICOS-Fc inhibited the development of lung metastases upon injection of NOD-SCID-IL2Rγnull mice with CF-PAC1 cells, as well as C57BL/6 mice with B16-F10 cells. Therefore, the B7h-ICOS interaction may modulate the spread of cancer metastases, which suggests the novel use of ICOS-Fc as an immunomodulatory drug. However, in the B16-F10-metastasized lungs, ICOS-Fc also increased IL-17A/RORc and decreased IL-10/Foxp3 expression, which indicates that it also exerts positive effects on the antitumor immune response. PMID:24729612

  2. Ginseng saponin metabolite 20(S)-protopanaxadiol inhibits tumor growth by targeting multiple cancer signaling pathways

    PubMed Central

    GAO, JIAN-LI; LV, GUI-YUAN; HE, BAI-CHENG; ZHANG, BING-QIANG; ZHANG, HONGYU; WANG, NING; WANG, CHONG-ZHI; DU, WEI; YUAN, CHUN-SU; HE, TONG-CHUAN

    2013-01-01

    Plant-derived active constituents and their semi-synthetic or synthetic analogs have served as major sources of anticancer drugs. 20(S)-protopanaxadiol (PPD) is a metabolite of ginseng saponin of both American ginseng (Panax quinquefolius L.) and Asian ginseng (Panax ginseng C.A. Meyer). We previously demonstrated that ginsenoside Rg3, a glucoside precursor of PPD, exhibits anti-proliferative effects on HCT116 cells and reduces tumor size in a xenograft model. Our subsequent study indicated that PPD has more potent antitumor activity than that of Rg3 in vitro although the mechanism underlying the anticancer activity of PPD remains to be defined. Here, we investigated the mechanism underlying the anticancer activity of PPD in human cancer cells in vitro and in vivo. PPD was shown to inhibit growth and induce cell cycle arrest in HCT116 cells. The in vivo studies indicate that PPD inhibits xenograft tumor growth in athymic nude mice bearing HCT116 cells. The xenograft tumor size was significantly reduced when the animals were treated with PPD (30 mg/kg body weight) for 3 weeks. When the expression of previously identified Rg3 targets, A kinase (PRKA) anchor protein 8 (AKAP8L) and phosphatidylinositol transfer protein α (PITPNA), was analyzed, PPD was shown to inhibit the expression of PITPNA while upregulating AKAP8L expression in HCT116 cells. Pathway-specific reporter assays indicated that PPD effectively suppressed the NF-κB, JNK and MAPK/ERK signaling pathways. Taken together, our results suggest that the anticancer activity of PPD in colon cancer cells may be mediated through targeting NF-κB, JNK and MAPK/ERK signaling pathways, although the detailed mechanisms underlying the anticancer mode of PPD action need to be fully elucidated. PMID:23633038

  3. Enhancement of glioblastoma radioresponse by a selective COX-2 inhibitor celecoxib: Inhibition of tumor angiogenesis with extensive tumor necrosis

    SciTech Connect

    Kang, Khong Bee . E-mail: dmskkb@nccs.com.sg; Wang, Ting Ting; Woon, Chow Thai; Cheah, Elizabeth S.; Moore, Xiao Lei; Zhu Congju; Wong, Meng Cheong

    2007-03-01

    Purpose: Toward improved glioblastoma multiforme treatment, we determined whether celecoxib, a selective cyclooxygenase (COX)-2 inhibitor, could enhance glioblastoma radiosensitivity by inducing tumor necrosis and inhibiting tumor angiogenesis. Methods and Materials: U-87MG cells treated with celecoxib, irradiation, or both were assayed for clonogenic survival and angiogenic factor protein analysis (angiopoietin-1, angiopoietin-2, and vascular endothelial growth factor [VEGF]). In vivo, survival of mice intracranially implanted with U-87MG cells and treated with celecoxib and/or irradiation was monitored. Isolated tumors were assessed for tumor necrosis and tumor microvascular density by von Williebrand's factor (vWF) immunohistochemical staining. Results: Celecoxib (4 and 30 {mu}M; 24, 48, and 72 h) enhanced U-87MG cell radiosensitivity by significantly reducing clonogenic survival of irradiated cells. Angiopoietin-1 and VEGF proteins were decreased, whereas angiopoietin-2 expression increased after 72 h of celecoxib alone and when combined with irradiation. In vivo, median survival of control mice intracranially implanted with U-87MG cells was 18 days. Celecoxib (100 mg/kg/day, 2 weeks) significantly extended median survival of irradiated mice (24 Gy total) from 34 to 41 days, with extensive tumor necrosis [24.5 {+-} 8.6% of tumor region, compared with irradiation alone (2.7 {+-} 1.8%)]. Tumor microvascular density was significantly reduced in combined celecoxib and irradiated tumors (52.5 {+-} 2.9 microvessels per mm{sup 2} tumor region), compared with irradiated tumors alone (65.4 {+-} 4.0 microvessels per mm{sup 2}). Conclusion: Celecoxib significantly enhanced glioblastoma radiosensitivity, reduced clonogenic survival, and prolonged survival of glioblastoma-implanted mice by inhibition of tumor angiogenesis with extensive tumor necr0010os.

  4. 3'-deoxy-3'-[18F]fluorothymidine positron emission tomography is a sensitive method for imaging the response of BRAF-dependent tumors to MEK inhibition.

    PubMed

    Solit, David B; Santos, Elmer; Pratilas, Christine A; Lobo, Jose; Moroz, Maxim; Cai, Shangde; Blasberg, Ronald; Sebolt-Leopold, Judith; Larson, Steven; Rosen, Neal

    2007-12-01

    Activating mutations of BRAF occur in approximately 7% of all human tumors and in the majority of melanomas. These tumors are very sensitive to pharmacologic inhibition of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK), which causes loss of D-cyclin expression, hypophosphorylation of Rb, and G(1) arrest. Growth arrest is followed by differentiation or senescence and, in a subset of BRAF mutant tumors, by apoptosis. The former effects result in so-called "stable disease" and, in patients with cancer, can be difficult to distinguish from indolent tumor growth. The profound G(1) arrest induced by MEK inhibition in BRAF mutant tumors is associated with a marked decline in thymidine uptake and is therefore potentially detectable in vivo by noninvasive 3'-deoxy-3'-[(18)F]fluorothymidine ([(18)F]FLT) positron emission tomography (PET) imaging. In SKMEL-28 tumor xenografts, MEK inhibition completely inhibited tumor growth and induced differentiation with only modest tumor regression. MEK inhibition also resulted in a rapid decline in the [(18)F]FLT signal in V600E BRAF mutant SKMEL-28 xenografts but not in BRAF wild-type BT-474 xenografts. The data suggest that [(18)F]FLT PET can effectively image induction of G(1) arrest by MEK inhibitors in mutant BRAF tumors and may be a useful noninvasive method for assessing the early biological response to this class of drugs. PMID:18056475

  5. Inhibition of metastatic tumor growth by targeted delivery of antioxidant enzymes.

    PubMed

    Nishikawa, Makiya; Hyoudou, Kenji; Kobayashi, Yuki; Umeyama, Yukari; Takakura, Yoshinobu; Hashida, Mitsuru

    2005-12-01

    To develop effective anti-metastatic therapy, targeted or sustained delivery of catalase was examined in mice. We found that mouse lung with metastatic colonies of adenocarcinoma colon26 cells exhibited reduced catalase activity. The interaction of the tumor cells with macrophages or hepatocytes generated detectable amounts of ROS, and increased the activity of matrix metalloproteinases. Hepatocyte-targeted delivery of catalase was successfully achieved by galactosylation, which was highly effective in inhibiting the hepatic metastasis of colon26 cells. PEGylation, which increased the retention of catalase in the circulation, effectively inhibited the pulmonary metastasis of the cells. To examine which processes in tumor metastasis are inhibited by catalase derivatives, the tissue distribution and proliferation of tumor cells in mice was quantitatively analyzed using firefly luciferase-expressing tumor cells. An injection of PEG-catalase just before the inoculation of melanoma B16-BL6/Luc cells significantly reduced the number of the tumor cells in the lung at 24 h. Daily dosing of PEG-catalase greatly inhibited the proliferation of the tumor cells, and increased the survival rate of the tumor-bearing mice. These results indicate that targeted or sustained delivery of catalase to sites where tumor cells metastasize is a promising approach for inhibiting metastatic tumor growth. PMID:16256238

  6. Tumor growth suppression by inhibiting both autophagy and STAT3 signaling in HNSCC

    PubMed Central

    Wang, Wei-Ming; Ma, Si-Rui; Liu, Jian-Feng; Deng, Wei-Wei; Mao, Liang; Yu, Guang-Tao; Huang, Cong-Fa; Liu, Bing; Zhang, Wen-Feng; Sun, Zhi-Jun

    2015-01-01

    Autophagy is considered as a double-edged sword. It can prolong the survival of cancer cells and enhance its resistance to apoptosis, and paradoxically, defective autophagy has been linked to increased tumorigenesis, but the mechanism behind this phenomenon is unclear. In this study, we demonstrated that decreased phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) was correlated with increased autophagy through the Akt/mTOR and Erk signaling pathways in human head and neck squamous cell carcinoma (HNSCC). We also showed that blockage of STAT3 by NSC74859 could markedly induce apoptotic cell death and autophagy. Meanwhile, increased autophagy inhibited apoptosis. The pharmacological or genetic inhibition of autophagy and STAT3 further sensitized HNSCC cells to apoptosis. Furthermore, evidence from xenograft model proved that suppressed STAT3 activity combined with inhibition of autophagy promoted tumor regression better than either treatment alone. Taken together, this present study demonstrated that autophagy alleviates apoptotic cell death in HNSCC, and combination of inhibition of STAT3 by NSC74859 and autophagy might be a promising new therapeutic strategy for HNSCC. PMID:26561201

  7. Myristica fragrans Suppresses Tumor Growth and Metabolism by Inhibiting Lactate Dehydrogenase A.

    PubMed

    Kim, Eun-Yeong; Choi, Hee-Jung; Park, Mi-Ju; Jung, Yeon-Seop; Lee, Syng-Ook; Kim, Keuk-Jun; Choi, Jung-Hye; Chung, Tae-Wook; Ha, Ki-Tae

    2016-01-01

    Most cancer cells predominantly produce ATP by maintaining a high rate of lactate fermentation, rather than by maintaining a comparatively low rate of tricarboxylic acid cycle, i.e., Warburg's effect. In the pathway, the pyruvate produced by glycolysis is converted to lactic acid by lactate dehydrogenase (LDH). Here, we demonstrated that water extracts from the seeds of Myristica fragrans Houtt. (MF) inhibit the in vitro enzymatic activity of LDH. MF effectively suppressed cell growth and the overall Warburg effect in HT29 human colon cancer cells. Although the expression of LDH-A was not changed by MF, both lactate production and LDH activity were decreased in MF-treated cells under both normoxic and hypoxic conditions. In addition, intracellular ATP levels were also decreased by MF treatment, and the uptake of glucose was also reduced by MF treatment. Furthermore, the experiment on tumor growth in the in vivo mice model revealed that MF effectively reduced the growth of allotransplanted Lewis lung carcinoma cells. Taken together, these results suggest that MF effectively inhibits cancer growth and metabolism by inhibiting the activity of LDH, a major enzyme responsible for regulating cancer metabolism. These results implicate MF as a potential candidate for development into a novel drug against cancer through inhibition of LDH activity. PMID:27430914

  8. Piperlongumine inhibits lung tumor growth via inhibition of nuclear factor kappa B signaling pathway.

    PubMed

    Zheng, Jie; Son, Dong Ju; Gu, Sun Mi; Woo, Ju Rang; Ham, Young Wan; Lee, Hee Pom; Kim, Wun Jae; Jung, Jae Kyung; Hong, Jin Tae

    2016-01-01

    Piperlongumine has anti-cancer activity in numerous cancer cell lines via various signaling pathways. But there has been no study regarding the mechanisms of PL on the lung cancer yet. Thus, we evaluated the anti-cancer effects and possible mechanisms of PL on non-small cell lung cancer (NSCLC) cells in vivo and in vitro. Our findings showed that PL induced apoptotic cell death and suppressed the DNA binding activity of NF-κB in a concentration dependent manner (0-15 μM) in NSCLC cells. Docking model and pull down assay showed that PL directly binds to the DNA binding site of nuclear factor-κB (NF-κB) p50 subunit, and surface plasmon resonance (SPR) analysis showed that PL binds to p50 concentration-dependently. Moreover, co-treatment of PL with NF-κB inhibitor phenylarsine oxide (0.1 μM) or p50 siRNA (100 nM) augmented PL-induced inhibitory effect on cell growth and activation of Fas and DR4. Notably, co-treatment of PL with p50 mutant plasmid (C62S) partially abolished PL-induced cell growth inhibition and decreased the enhanced expression of Fas and DR4. In xenograft mice model, PL (2.5-5 mg/kg) suppressed tumor growth of NSCLC dose-dependently. Therefore, these results indicated that PL could inhibit lung cancer cell growth via inhibition of NF-κB signaling pathway in vitro and in vivo. PMID:27198178

  9. Piperlongumine inhibits lung tumor growth via inhibition of nuclear factor kappa B signaling pathway

    PubMed Central

    Zheng, Jie; Son, Dong Ju; Gu, Sun Mi; Woo, Ju Rang; Ham, Young Wan; Lee, Hee Pom; Kim, Wun Jae; Jung, Jae Kyung; Hong, Jin Tae

    2016-01-01

    Piperlongumine has anti-cancer activity in numerous cancer cell lines via various signaling pathways. But there has been no study regarding the mechanisms of PL on the lung cancer yet. Thus, we evaluated the anti-cancer effects and possible mechanisms of PL on non-small cell lung cancer (NSCLC) cells in vivo and in vitro. Our findings showed that PL induced apoptotic cell death and suppressed the DNA binding activity of NF-κB in a concentration dependent manner (0–15 μM) in NSCLC cells. Docking model and pull down assay showed that PL directly binds to the DNA binding site of nuclear factor-κB (NF-κB) p50 subunit, and surface plasmon resonance (SPR) analysis showed that PL binds to p50 concentration-dependently. Moreover, co-treatment of PL with NF-κB inhibitor phenylarsine oxide (0.1 μM) or p50 siRNA (100 nM) augmented PL-induced inhibitory effect on cell growth and activation of Fas and DR4. Notably, co-treatment of PL with p50 mutant plasmid (C62S) partially abolished PL-induced cell growth inhibition and decreased the enhanced expression of Fas and DR4. In xenograft mice model, PL (2.5–5 mg/kg) suppressed tumor growth of NSCLC dose-dependently. Therefore, these results indicated that PL could inhibit lung cancer cell growth via inhibition of NF-κB signaling pathway in vitro and in vivo. PMID:27198178

  10. An epitope-specific novel anti-EMMPRIN polyclonal antibody inhibits tumor progression

    PubMed Central

    Walter, Miriam; Simanovich, Elina; Brod, Vera; Lahat, Nitza; Bitterman, Haim; Rahat, Michal A.

    2016-01-01

    ABSTRACT Extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) mediates tumor cell–macrophage interactions, and has been shown to induce both matrix metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF). However, the epitope responsible for MMP induction is controversial, and the epitope responsible for VEGF induction is yet unknown. We generated a novel anti-EMMPRIN antibody directed against a specific epitope that successfully inhibited the production of both MMP-9 and VEGF in tumor cell–macrophage in vitro co-culture systems, exhibiting a U-shaped dose response. Furthermore, this antibody efficiently inhibited in vivo tumor progression in both the RENCA renal cell carcinoma and CT26 colon carcinoma subcutaneous tumor models, and reduced tumor size and number of metastatic foci in the 4T1 orthotopic model. This was achieved by inhibiting angiogenesis as assessed by immunohistochemical staining for the endothelial marker CD31, by inhibiting tumor cell proliferation as assessed by the staining for Ki-67, and by enhancing tumor cell apoptosis as assessed in the TUNEL assay. Moreover, administration of the antibody recruited more macrophages into the tumor, and skewed the tumor microenvironment for macrophages from TGFβ-dominated anti-inflammatory microenvironment, to a less immunosuppressive one. The antibody improved the ability of stimulated macrophages to perform antibody-dependent cell cytotoxicity (ADCC) and kill tumor cells. Thus, our new antibody maps the epitope capable of inducing both MMPs and VEGF, and places EMMPRIN as a good target for cancer therapy. PMID:27057452

  11. Violacein induces p44/42 mitogen-activated protein kinase-mediated solid tumor cell death and inhibits tumor cell migration

    PubMed Central

    MEHTA, TORAL; VERCRUYSSE, KOEN; JOHNSON, TERRANCE; EJIOFOR, ANTHONY OKECHUKWU; MYLES, ELBERT; QUICK, QUINCY ANTOINE

    2015-01-01

    Microbial secondary metabolites have emerged as alternative novel drugs for the treatment of human cancers. Violacein, a purple pigment produced by Chromobacterium violaceum, was investigated in the present study for its anti-tumor properties in tumor cell lines. Clinically applicable concentrations of violacein were demonstrated to inhibit the proliferative capacity of tumor cell lines according to a crystal violet proliferation assay. The underlying mechanism was the promotion of apoptotic cell death, as indicated by poly(ADP ribose) polymerase cleavage and p44/42 mitogen-activated protein kinase signaling determined by western blot analysis. Collectively, this provided mechanistic evidence that violacein elicits extracellular-signal regulated kinase-induced apoptosis via the intrinsic pathway. The anti-malignant properties of violacein in the present study were further demonstrated by its inhibitory effects on brain tumor cell migration, specifically glioblastomas, one of the most invasive and therapeutically resistant neoplasms in the clinic. Additionally, solid tumors examined in the present study displayed differential cellular responses and sensitivities to violacein as observed by morphologically induced cellular changes that contributed to its anti-migratory properties. In conclusion, violacein is a novel natural product with the potential to kill several types of human tumor cell lines, as well as prevent disease recurrence by antagonizing cellular processes that contribute to metastatic invasion. PMID:25816226

  12. Isolated tumoral pyruvate dehydrogenase can synthesize acetoin which inhibits pyruvate oxidation as well as other aldehydes.

    PubMed

    Baggetto, L G; Lehninger, A L

    1987-05-29

    Oxidation of 1 mM pyruvate by Ehrlich and AS30-D tumor mitochondria is inhibited by acetoin, an unusual and important metabolite of pyruvate utilization by cancer cells, by acetaldehyde, methylglyoxal and excess pyruvate. The respiratory inhibition is reversed by other substrates added to pyruvate and also by 0.5 mM ATP. Kinetic properties of pyruvate dehydrogenase complex isolated from these tumor mitochondria have been studied. This complex appears to be able to synthesize acetoin from acetaldehyde plus pyruvate and is competitively inhibited by acetoin. The role of a new regulatory pattern for tumoral pyruvate dehydrogenase is presented. PMID:3593337

  13. Human bactericidal/permeability-increasing protein and a recombinant NH2-terminal fragment cause killing of serum-resistant gram-negative bacteria in whole blood and inhibit tumor necrosis factor release induced by the bacteria.

    PubMed Central

    Weiss, J; Elsbach, P; Shu, C; Castillo, J; Grinna, L; Horwitz, A; Theofan, G

    1992-01-01

    The bactericidal/permeability-increasing protein (BPI) of neutrophils and BPI fragments neutralize the effects of isolated Gram-negative bacterial lipopolysaccharides both in vitro and in vivo. Since endotoxin most commonly enters the host as constituents of invading Gram-negative bacteria, we raised the question: Can BPI and its bioactive fragments also protect against whole bacteria? To determine whether the bactericidal and endotoxin-neutralizing activities of BPI/fragments are expressed when Gram-negative bacteria are introduced to the complex environment of whole blood we examined the effects of added BPI and proteolytically prepared and recombinant NH2-terminal fragments on: (a) the fate of serum-resistant encapsulated Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa that survive the antibacterial actions of whole blood and (b) the ability of these bacteria to trigger cytokine release. Added BPI in nanomolar concentrations killed each of three encapsulated strains of E. coli and in closely parallel fashion inhibited tumor necrosis factor (TNF) release. Holo-BPI and its NH2-terminal fragment were equipotent toward a rough LPS chemotype K1-encapsulated strain, but the fragment was substantially more potent than holo-BPI toward two encapsulated smooth LPS chemotype strains. TNF release induced by K. pneumoniae and P. aeruginosa was also inhibited by both holo-BPI and fragment but, at the protein concentrations tested, P. aeruginosa was killed only by the fragment and K. pneumoniae was not killed by either protein. The bactericidal action of BPI/fragment toward E. coli is inhibited by C7-depleted serum, but accelerated by normal serum, indicating that BPI, acting in synergy with late complement components, enhances extracellular killing of serum-resistant bacteria. Thus, BPI and an even more potent NH2-terminal fragment may protect against Gram-negative bacteria in the host by blocking bacterial proliferation as well as endotoxin

  14. Patient-Derived Tumor Xenografts Are Susceptible to Formation of Human Lymphocytic Tumors1

    PubMed Central

    Bondarenko, Gennadiy; Ugolkov, Andrey; Rohan, Stephen; Kulesza, Piotr; Dubrovskyi, Oleksii; Gursel, Demirkan; Mathews, Jeremy; O’Halloran, Thomas V.; Wei, Jian J.; Mazar, Andrew P.

    2015-01-01

    Patient-derived xenograft (PDX) tumor models have emerged as a new approach to evaluate the effects of cancer drugs on patients’ personalized tumor grafts enabling to select the best treatment for the cancer patient and providing a new tool for oncology drug developers. Here, we report that human tumors engrafted in immunodeficient mice are susceptible to formation of B-and T-cell PDX tumors. We xenografted human primary and metastatic tumor samples into immunodeficient mice and found that a fraction of PDX tumors generated from patients’ samples of breast, colon, pancreatic, bladder and renal cancer were histologically similar to lymphocytic neoplasms. Moreover, we found that the first passage of breast and pancreatic cancer PDX tumors after initial transplantation of the tumor pieces from the same human tumor graft could grow as a lymphocytic tumor in one mouse and as an adenocarcinoma in another mouse. Whereas subcutaneous PDX tumors resembling human adenocarcinoma histology were slow growing and non-metastatic, we found that subcutaneous PDX lymphocytic tumors were fast growing and formed large metastatic lesions in mouse lymph nodes, liver, lungs, and spleen. PDX lymphocytic tumors were comprised of B-cells which were Epstein-Barr virus positive and expressed CD45 and CD20. Because B-cells are typically present in malignant solid tumors, formation of B-cell tumor may evolve in a wide range of PDX tumor models. Although PDX tumor models show great promise in the development of personalized therapy for cancer patients, our results suggest that confidence in any given PDX tumor model requires careful screening of lymphocytic markers. PMID:26476081

  15. The RAF inhibitor PLX4032 inhibits ERK signaling and tumor cell proliferation in a V600E BRAF-selective manner

    PubMed Central

    Joseph, Eric W.; Pratilas, Christine A.; Poulikakos, Poulikos I.; Tadi, Madhavi; Wang, Weiqing; Taylor, Barry S.; Halilovic, Ensar; Persaud, Yogindra; Xing, Feng; Viale, Agnes; Tsai, James; Chapman, Paul B.; Bollag, Gideon; Solit, David B.; Rosen, Neal

    2010-01-01

    Tumors with mutant BRAF and some with mutant RAS are dependent upon ERK signaling for proliferation, and their growth is suppressed by MAPK/ERK kinase (MEK) inhibitors. In contrast, tumor cells with human EGF receptor (HER) kinase activation proliferate in a MEK-independent manner. These findings have led to the development of RAF and MEK inhibitors as anticancer agents. Like MEK inhibitors, the RAF inhibitor PLX4032 inhibits the proliferation of BRAFV600E tumor cells but not that of HER kinase-dependent tumors. However, tumors with RAS mutation that are sensitive to MEK inhibition are insensitive to PLX4032. MEK inhibitors inhibit ERK phosphorylation in all normal and tumor cells, whereas PLX4032 inhibits ERK signaling only in tumor cells expressing BRAFV600E. In contrast, the drug activates MEK and ERK phosphorylation in cells with wild-type BRAF. In BRAFV600E tumor cells, MEK and RAF inhibitors affect the expression of a common set of genes. PLX4032 inhibits ERK signaling output in mutant BRAF cells, whereas it transiently activates the expression of these genes in tumor cells with wild-type RAF. Thus, PLX4032 inhibits ERK signaling output in a mutant BRAF-selective manner. These data explain why the drug selectively inhibits the growth of mutant BRAF tumors and suggest that it will not cause toxicity resulting from the inhibition of ERK signaling in normal cells. This selectivity may lead to a broader therapeutic index and help explain the greater antitumor activity observed with this drug than with MEK inhibitors. PMID:20668238

  16. Tetramethylpyrazine inhibits tumor growth of lung cancer through disrupting angiogenesis via BMP/Smad/Id-1 signaling.

    PubMed

    Jia, Youchao; Wang, Zhigang; Zang, Aimin; Jiao, Shunchang; Chen, Sumei; Fu, Yan

    2016-05-01

    The underlying mechanisms of inhibitory effects induced by tetramethylpyrazine (TMP) on angiogenesis and tumor growth of lung cancer were investigated. In vitro cell proliferation, migration, and tube formation of human microvascular endothelial cells (HMEC-1) were evaluated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-dephenyltetrazolium bromide (MTT), wound healing, Transwell, and Matrigel assays. The expression of BMP/Smad/Id-1 signals was detected by RT-PCR and western blotting. In an A549 xenograft tumor model, TMP (40 and 80 mg/kg/day) was intraperitoneally injected into mice. The expressions of CD31, phosphorylated Smad1/5/8, and Id-1 were measured by immunohistochemistry. We demonstrated that TMP inhibited proliferation, migration, and capillary tube formation of HMEC-1 in a dose- and time-dependent manner. Furthermore, treatment of HMEC-1 cells with TMP (0.4 mg/ml) significantly upregulated BMP2 expression and downregulated BMPRIA, BMPRII, phosphorylated Smad1/5/8, and Id-1 expression. In addition, administrations of TMP remarkably inhibited tumor growth of A549 xenograft in nude mice. The CD31, phosphorylated Smad1/5/8, and Id-1 expression were significantly inhibited in TMP-treated xenograft tumors compared with the vehicle. In conclusion, our results indicated that TMP suppressed angiogenesis and tumor growth of lung cancer via blocking the BMP/Smad/Id-1 signaling. PMID:26984046

  17. DSGOST inhibits tumor growth by blocking VEGF/VEGFR2-activated angiogenesis

    PubMed Central

    Choi, Hyeong Sim; Lee, Kangwook; Kim, Min Kyoung; Lee, Kang Min; Shin, Yong Cheol; Cho, Sung-Gook; Ko, Seong-Gyu

    2016-01-01

    Tumor growth requires a process called angiogenesis, a new blood vessel formation from pre-existing vessels, as newly formed vessels provide tumor cells with oxygen and nutrition. Danggui-Sayuk-Ga-Osuyu-Saenggang-Tang (DSGOST), one of traditional Chinese medicines, has been widely used in treatment of vessel diseases including Raynaud's syndrome in Northeast Asian countries including China, Japan and Korea. Therefore, we hypothesized that DSGOST might inhibit tumor growth by targeting newly formed vessels on the basis of its historical prescription. Here, we demonstrate that DSGOST inhibits tumor growth by inhibiting VEGF-induced angiogenesis. DSGOST inhibited VEGF-induced angiogenic abilities of endothelial cells in vitro and in vivo, which resulted from its inhibition of VEGF/VEGFR2 interaction. Furthermore, DSGOST attenuated pancreatic tumor growth in vivo by reducing angiogenic vessel numbers, while not affecting pancreatic tumor cell viability. Thus, our data conclude that DSGOST inhibits VEGF-induced tumor angiogenesis, suggesting a new indication for DSGOST in treatment of cancer. PMID:26967562

  18. Glioma oncoprotein Bcl2L12 inhibits the p53 tumor suppressor

    PubMed Central

    Stegh, Alexander H.; Brennan, Cameron; Mahoney, John A.; Forloney, Kristin L.; Jenq, Harry T.; Luciano, Janina P.; Protopopov, Alexei; Chin, Lynda; DePinho, Ronald A.

    2010-01-01

    Glioblastoma multiforme (GBM) is a lethal brain tumor characterized by intense apoptosis resistance and extensive necrosis. Bcl2L12 (for Bcl2-like 12) is a cytoplasmic and nuclear protein that is overexpressed in primary GBM and functions to inhibit post-mitochondrial apoptosis signaling. Here, we show that nuclear Bcl2L12 physically and functionally interacts with the p53 tumor suppressor, as evidenced by the capacity of Bcl2L12 to (1) enable bypass of replicative senescence without concomitant loss of p53 or p19Arf, (2) inhibit p53-dependent DNA damage-induced apoptosis, (3) impede the capacity of p53 to bind some of its target gene promoters, and (4) attenuate endogenous p53-directed transcriptomic changes following genotoxic stress. Correspondingly, The Cancer Genome Atlas profile and tissue protein analyses of human GBM specimens show significantly lower Bcl2L12 expression in the setting of genetic p53 pathway inactivation. Thus, Bcl2L12 is a multifunctional protein that contributes to intense therapeutic resistance of GBM through its ability to operate on two key nodes of cytoplasmic and nuclear signaling cascades. PMID:20837658

  19. A DNA vaccine targeting angiomotin inhibits angiogenesis and suppresses tumor growth

    NASA Astrophysics Data System (ADS)

    Holmgren, Lars; Ambrosino, Elena; Birot, Olivier; Tullus, Carl; Veitonmäki, Niina; Levchenko, Tetyana; Carlson, Lena-Maria; Musiani, Piero; Iezzi, Manuela; Curcio, Claudia; Forni, Guido; Cavallo, Federica; Kiessling, Rolf

    2006-06-01

    Endogenous angiogenesis inhibitors have shown promise in preclinical trials, but clinical use has been hindered by low half-life in circulation and high production costs. Here, we describe a strategy that targets the angiostatin receptor angiomotin (Amot) by DNA vaccination. The vaccination procedure generated antibodies that detected Amot on the endothelial cell surface. Purified Ig bound to the endothelial cell membrane and inhibited endothelial cell migration. In vivo, DNA vaccination blocked angiogenesis in the matrigel plug assay and prevented growth of transplanted tumors for up to 150 days. We further demonstrate that a combination of DNA vaccines encoding Amot and the extracellular and transmembrane domains of the human EGF receptor 2 (Her-2)/neu oncogene inhibited breast cancer progression and impaired tumor vascularization in Her-2/neu transgenic mice. No toxicity or impairment of normal blood vessels could be detected. This work shows that DNA vaccination targeting Amot may be used to mimic the effect of angiostatin. cancer vaccines | neoplasia | neovascularization | breast cancer | angiostatin

  20. Inhibition of metastasis, angiogenesis, and tumor growth by Chinese herbal cocktail Tien-Hsien Liquid

    PubMed Central

    2010-01-01

    Background Advanced cancer is a multifactorial disease that demands treatments targeting multiple cellular pathways. Chinese herbal cocktail which contains various phytochemicals may target multiple dys-regulated pathways in cancer cells and thus may provide an alternative/complementary way to treat cancers. Previously we reported that the Chinese herbal cocktail Tien-Hsien Liguid (THL) can specifically induce apoptosis in various cancer cells and have immuno-modulating activity. In this study, we further evaluated the anti-metastatic, anti-angiogenic and anti-tumor activities of THL with a series of in vitro and in vivo experiments. Methods The migration and invasion of cancer cells and endothelial cells was determined by Boyden chamber transwell assays. The effect of THL on pulmonary metastasis was done by injecting CT-26 colon cancer cells intravenously to syngenic mice. The in vitro and in vivo microvessel formation was determined by the tube formation assay and the Matrigel plug assay, respectively. The in vivo anti-tumor effect of THL was determined by a human MDA-MB-231 breast cancer xenograft model. The expression of metalloproteinase (MMP)-2, MMP-9, and urokinase plasminogen activator (uPA) was measured by gelatin zymography. The expression of HIF-1α and the phosphorylation of ERK1/2 were determined by Western blot. Results THL inhibited the migration and invasion ability of various cancer cells in vitro, decreased the secretion of MMP-2, MMP-9, and uPA and the activity of ERK1/2 in cancer cells, and suppressed pulmonary metastasis of CT-26 cancer cells in syngenic mice. Moreover, THL inhibited the migration, invasion, and tube formation of endothelial cells in vitro, decreased the secretion of MMP-2 and uPA in endothelial cells, and suppressed neovascularization in Matrigel plugs in mice. Besides its inhibitory effect on endothelial cells, THL inhibited hypoxia-induced HIF-1α and vascular endothelial growth factor-A expression in cancer cells. Finally

  1. Experimental chemotherapy of human tumors heterotransplanted in nude mice.

    PubMed

    Giovanella, B C

    1980-01-01

    Human tumors heterotransplanted in nude mice offer the most realistic model for experimental chemotherapy of human neoplasms. Almost all the known human malignancies have been successfully transplanted in the nudes, although the rate of takes varies considerably between different tumor types. So far, a good correlation has been observed between the results obtained treating with the same drug the same tumor in the patient and in the nude mouse. Our experience in this field is, however, still too limited for the direct extrapolation of chemotherapeutic results obtained in the nudes to human tumors. PMID:6998362

  2. Inhibition of adhesion and proliferation of peritoneally disseminated tumor cells by pegylated catalase.

    PubMed

    Hyoudou, Kenji; Nishikawa, Makiya; Kobayashi, Yuki; Kuramoto, Yukari; Yamashita, Fumiyoshi; Hashida, Mitsuru

    2006-01-01

    Hydrogen peroxide may aggravate the peritoneal dissemination of tumor cells by activating the expression of a variety of genes. In this study, we used pegylated catalase (PEG-catalase) to examine whether prolonged retention of catalase activity within the peritoneal cavity is effective in inhibiting peritoneal dissemination in mouse models. Murine B16-BL6 cells or colon 26 cells labeled with firefly luciferase gene were inoculated intraperitoneally into syngeneic mice. Compared with unmodified catalase, PEG-catalase was retained in the peritoneal cavity for a long period after intraperitoneal injection. A single injection of PEG-catalase just before tumor inoculation significantly reduced the number of the tumor cells at 1 and 7 days. The changes in the expression of molecules involved in the metastasis were evaluated by real time quantitative PCR analysis. Inoculation of the tumor cells increased the expression of intercellular adhesion molecule (ICAM)-1 in the greater omentum, which was inhibited by PEG-catalase. An injection of PEG-catalase at 3 days after tumor inoculation also reduced the number of the tumor cells, suggesting that processes other than the adhesion of tumor cells to peritoneal organs are also inhibited. Daily doses of PEG-catalase significantly prolonged the survival time of tumor-bearing mice. These results indicate that intraperitoneal injection of PEG-catalase inhibits the multiple processes of peritoneal dissemination of tumor cells by scavenging hydrogen peroxide in the peritoneal cavity. PMID:17086358

  3. Dopamine receptor antagonist thioridazine inhibits tumor growth in a murine breast cancer model.

    PubMed

    Yin, Tao; He, Sisi; Shen, Guobo; Ye, Tinghong; Guo, Fuchun; Wang, Yongsheng

    2015-09-01

    Neuropsychological factors have been shown to influence tumor progression and therapeutic response. The present study investigated the effect of the dopamine receptor antagonist thioridazine on murine breast cancer. The anti‑tumor efficacy of thioridazine was assessed using a murine breast cancer model. Cell apoptosis and proliferation were analyzed in vitro using flow cytometry (FCM) and the MTT assay, respectively. Western blot analysis was performed to assess Akt, phosphorylated (p)‑Akt, signal transducer and activator of transcription (STAT) 3, p‑STAT3 and p‑p65 in tumor cells following treatment with thioridazine. The Ki67 index and the number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)‑positive apoptotic cells were assessed in the tumor sections. Thioridazine was found to reduce tumor growth, inhibit tumor cell proliferation and induce apoptosis in a dose‑ and time‑dependent manner in vitro. Thioridazine was also found to markedly inhibit tumor proliferation and induce tumor cell apoptosis in vivo as shown by the lower Ki67 index and increase in TUNEL‑positive cells. In addition, thioridazine was observed to inhibit the activation of the canonical nuclear factor κ‑light‑chain‑enhancer of activated B cells pathway and exert anti‑tumor effects by remodeling the tumor stroma, as well as inhibit angiogenesis in the tumor microenvironment. In conclusion, thioridazine was found to significantly inhibit breast tumor growth and the potential for thioridazine to be used in cancer therapy may be re‑evaluated and investigated in clinical settings. PMID:26095429

  4. GGNBP2 acts as a tumor suppressor by inhibiting estrogen receptor α activity in breast cancer cells.

    PubMed

    Lan, Zi-Jian; Hu, YunHui; Zhang, Sheng; Li, Xian; Zhou, Huaxin; Ding, Jixiang; Klinge, Carolyn M; Radde, Brandie N; Cooney, Austin J; Zhang, Jin; Lei, Zhenmin

    2016-07-01

    Gametogenetin-binding protein 2 (GGNBP2) is encoded in human chromosome 17q12-q23, a region known as a breast and ovarian cancer susceptibility locus. GGNBP2, also referred to ZFP403, has a single C2H2 zinc finger and a consensus LxxLL nuclear receptor-binding motif. Here, we demonstrate that GGNBP2 expression is reduced in primary human breast tumors and in breast cancer cell lines, including T47D, MCF-7, LCC9, LY2, and MDA-MB-231 compared with normal, immortalized estrogen receptor α (ERα) negative MCF-10A and MCF10F breast epithelial cells. Overexpression of GGNBP2 inhibits the proliferation of T47D and MCF-7 ERα positive breast cancer cells without affecting MCF-10A and MCF10F. Stable GGNBP2 overexpression in T47D cells inhibits 17β-estradiol (E2)-stimulated proliferation as well as migration, invasion, anchorage-independent growth in vitro, and xenograft tumor growth in mice. We further demonstrate that GGNBP2 protein physically interacts with ERα, inhibits E2-induced activation of estrogen response element-driven reporter activity, and attenuates ER target gene expression in T47D cells. In summary, our in vitro and in vivo findings suggest that GGNBP2 is a novel breast cancer tumor suppressor functioning as a nuclear receptor corepressor to inhibit ERα activity and tumorigenesis. PMID:27357812

  5. Radiofrequency thermal ablation of breast tumors combined with intralesional administration of IL-7 and IL-15 augments anti-tumor immune responses and inhibits tumor development and metastasis

    PubMed Central

    Habibi, Mehran; Kmieciak, Maciej; Graham, Laura; Morales, Johanna K; Bear, Harry D; Manjili, Masoud H

    2008-01-01

    Tumor development or recurrence is always a matter of concern following radiofrequency thermal ablation (RFA) of tumors. To determine whether combining RFA with immunologically active cytokines might induce tumor-specific immune responses against mammary carcinoma and inhibit tumor development or metastasis, we evaluated intralesional injection of IL-7 and IL-15 in RFA-treated murine tumors. We used two different breast carcinoma models: neu-overexpressing mouse mammary carcinoma (MMC) in FVBN202 transgenic mouse and 4T1 tumors in Balb/c mouse. MMC tend to relapse even in the presence of neu-specific immune responses, and 4T1 is a weakly immunogenic, aggressive and highly metastatic transplantable tumor. In vivo growth of both of these tumors is also associated with increased numbers of CD11b+Gr1+ myeloid-derived suppressor cells (MDSC). We showed for the first time that unlike RFA alone, RFA combined with the administration of intralesional IL-7 and IL-15 (after RFA), induced immune responses to tumors, inhibited tumor development and lung metastasis, and reduced MDSC. PMID:18425677

  6. Therapeutic silencing of miR-10b inhibits metastasis in a mouse mammary tumor model

    PubMed Central

    Ma, Li; Reinhardt, Ferenc; Pan, Elizabeth; Soutschek, Jürgen; Bhat, Balkrishen; Marcusson, Eric; Teruya-Feldstein, Julie; Bell, George W.; Weinberg, Robert A.

    2010-01-01

    MicroRNAs (miRNAs) are increasingly implicated in regulating metastasis. Despite progress in silencing miRNAs in normal tissues of rodents and non-human primates, the development of effective approaches for sequence-specific inhibition of miRNAs in fast-growing tumors remains a significant scientific and clinical challenge. Here we show that systemic treatment of tumor-bearing mice with miR-10b antagomirs – a class of chemically modified anti-miRNA oligonucleotides – suppresses breast cancer metastasis. Silencing of miR-10b both in vitro and in vivo with antagomirs significantly decreases miR-10b levels and increases levels of a functionally important miR-10b target, Hoxd10. Administration of miR-10b antagomirs to mice bearing highly metastatic cells does not reduce primary mammary tumor growth but instead markedly suppresses formation of lung metastases. This metastasis-suppressing effect is sequence-specific. The miR-10b antagomir, which is well tolerated by normal animals, appears to be a promising candidate and a starting point for the development of new anti-metastasis agents. PMID:20351690

  7. Inhibition of BRD4 suppresses tumor growth and enhances iodine uptake in thyroid cancer.

    PubMed

    Gao, Xuemei; Wu, Xinchao; Zhang, Xiao; Hua, Wenjuan; Zhang, Yajing; Maimaiti, Yusufu; Gao, Zairong; Zhang, Yongxue

    2016-01-15

    Thyroid cancer is a common malignancy of the endocrine system. Although radioiodine (131)I treatment on differentiated thyroid cancer is widely used, many patients still fail to benefit from (131)I therapy. Therefore, exploration of novel targeted therapies to suppress tumor growth and improve radioiodine uptake remains necessary. Bromodomain-containing protein 4 (BRD4) is an important member of the bromodomain and extra terminal domain family that influences transcription of downstream genes by binding to acetylated histones. In the present study, we found that BRD4 was up-regulated in thyroid cancer tissues and cell lines. Inhibition of BRD4 in thyroid cancer cells by JQ1 resulted in cell cycle arrest at G0/G1 phase and enhanced (131)I uptake in vitro and suppressed tumor growth in vivo. Moreover, JQ1 treatment suppressed C-MYC but enhanced NIS expression. We further demonstrated that BRD4 was enriched in the promoter region of C-MYC, which could be markedly blocked by JQ1 treatment. In conclusion, our findings revealed that the aberrant expression of BRD4 in thyroid cancer is possibly involved in tumor progression, and JQ1 is potentially an effective chemotherapeutic agent against human thyroid cancer. PMID:26707881

  8. The tumor microenvironment underlies acquired resistance to CSF-1R inhibition in gliomas.

    PubMed

    Quail, Daniela F; Bowman, Robert L; Akkari, Leila; Quick, Marsha L; Schuhmacher, Alberto J; Huse, Jason T; Holland, Eric C; Sutton, James C; Joyce, Johanna A

    2016-05-20

    Macrophages accumulate with glioblastoma multiforme (GBM) progression and can be targeted via inhibition of colony-stimulating factor-1 receptor (CSF-1R) to regress high-grade tumors in animal models of this cancer. However, whether and how resistance emerges in response to sustained CSF-1R blockade is unknown. We show that although overall survival is significantly prolonged, tumors recur in >50% of mice. Gliomas reestablish sensitivity to CSF-1R inhibition upon transplantation, indicating that resistance is tumor microenvironment-driven. Phosphatidylinositol 3-kinase (PI3K) pathway activity was elevated in recurrent GBM, driven by macrophage-derived insulin-like growth factor-1 (IGF-1) and tumor cell IGF-1 receptor (IGF-1R). Combining IGF-1R or PI3K blockade with CSF-1R inhibition in recurrent tumors significantly prolonged overall survival. Our findings thus reveal a potential therapeutic approach for treating resistance to CSF-1R inhibitors. PMID:27199435

  9. Ascitic and solid Ehrlich tumor inhibition by Chenopodium ambrosioides L. treatment.

    PubMed

    Nascimento, Flávia R F; Cruz, Gustavo V B; Pereira, Paulo Vitor S; Maciel, Márcia C G; Silva, Lucilene A; Azevedo, Ana Paula S; Barroqueiro, Elizabeth S B; Guerra, Rosane N M

    2006-04-25

    The leaves of Chenopodium ambrosioides L. [Chenopodiaceae] ('mastruz') have been indicated for the treatment of several diseases, among which the cancer. There are no results focusing the effect of C. ambrosioides treatment on tumor development in vivo. The aim of this study was to investigate the effect of treatment with C. ambrosioides on Ehrlich tumor development. Swiss mice were treated by intraperitoneal route (i.p.) with hydroalcoholic extract from leaves of C. ambrosioides (5 mg/kg) or with PBS (control group) 48 h before or 48 h later the Ehrlich tumor implantation. The tumor cells were implanted on the left footpad (solid tumor) or in the peritoneal cavity (ascitic tumor). To determine the solid tumor growth, footpad was measured each 2 days until the fourteenth day, when the feet were weighed. Ascitic tumor development was evaluated after 8 days of tumor implantation by quantification of the ascitic fluid volume and tumor cell number. The i.p. administration of C. ambrosioides extract before or after the tumor implantation significantly inhibited the solid and ascitic Ehrlich tumor forms. This inhibition was observed in ascitic tumor cell number, in the ascitic volume, in the tumor-bearing foot size and foot weight when compared to control mice. The treatments also increased the survival of tumor-bearing mice. In conclusion, C. ambrosioides has a potent anti-tumoral effect which was evident with a small dose and even when the treatment was given two days after the tumor implantation. This effect is probably related with anti-oxidant properties of C. ambrosioides. PMID:16307762

  10. Targeted Proapoptotic Peptides Depleting Adipose Stromal Cells Inhibit Tumor Growth.

    PubMed

    Daquinag, Alexes C; Tseng, Chieh; Zhang, Yan; Amaya-Manzanares, Felipe; Florez, Fernando; Dadbin, Ali; Zhang, Tao; Kolonin, Mikhail G

    2016-02-01

    Progression of many cancers is associated with tumor infiltration by mesenchymal stromal cells (MSC). Adipose stromal cells (ASC) are MSC that serve as adipocyte progenitors and endothelium-supporting cells in white adipose tissue (WAT). Clinical and animal model studies indicate that ASC mobilized from WAT are recruited by tumors. Direct evidence for ASC function in tumor microenvironment has been lacking due to unavailability of approaches to specifically inactivate these cells. Here, we investigate the effects of a proteolysis-resistant targeted hunter-killer peptide D-WAT composed of a cyclic domain CSWKYWFGEC homing to ASC and of a proapoptotic domain KLAKLAK2. Using mouse bone marrow transplantation models, we show that D-WAT treatment specifically depletes tumor stromal and perivascular cells without directly killing malignant cells or tumor-infiltrating leukocytes. In several mouse carcinoma models, targeted ASC cytoablation reduced tumor vascularity and cell proliferation resulting in hemorrhaging, necrosis, and suppressed tumor growth. We also validated a D-WAT derivative with a proapoptotic domain KFAKFAK2 that was found to have an improved cytoablative activity. Our results for the first time demonstrate that ASC, recruited as a component of tumor microenvironment, support cancer progression. We propose that drugs targeting ASC can be developed as a combination therapy complementing conventional cancer treatments. PMID:26316391

  11. The Selective PI3K Inhibitor XL147 (SAR245408) Inhibits Tumor Growth and Survival and Potentiates the Activity of Chemotherapeutic Agents in Preclinical Tumor Models.

    PubMed

    Foster, Paul; Yamaguchi, Kyoko; Hsu, Pin P; Qian, Fawn; Du, Xiangnan; Wu, Jianming; Won, Kwang-Ai; Yu, Peiwen; Jaeger, Christopher T; Zhang, Wentao; Marlowe, Charles K; Keast, Paul; Abulafia, Wendy; Chen, Jason; Young, Jenny; Plonowski, Artur; Yakes, F Michael; Chu, Felix; Engell, Kelly; Bentzien, Frauke; Lam, Sanh T; Dale, Stephanie; Yturralde, Olivia; Matthews, David J; Lamb, Peter; Laird, A Douglas

    2015-04-01

    Dysregulation of PI3K/PTEN pathway components, resulting in hyperactivated PI3K signaling, is frequently observed in various cancers and correlates with tumor growth and survival. Resistance to a variety of anticancer therapies, including receptor tyrosine kinase (RTK) inhibitors and chemotherapeutic agents, has been attributed to the absence or attenuation of downregulating signals along the PI3K/PTEN pathway. Thus, PI3K inhibitors have therapeutic potential as single agents and in combination with other therapies for a variety of cancer indications. XL147 (SAR245408) is a potent and highly selective inhibitor of class I PI3Ks (α, β, γ, and δ). Moreover, broad kinase selectivity profiling of >130 protein kinases revealed that XL147 is highly selective for class I PI3Ks over other kinases. In cellular assays, XL147 inhibits the formation of PIP3 in the membrane, and inhibits phosphorylation of AKT, p70S6K, and S6 in multiple tumor cell lines with diverse genetic alterations affecting the PI3K pathway. In a panel of tumor cell lines, XL147 inhibits proliferation with a wide range of potencies, with evidence of an impact of genotype on sensitivity. In mouse xenograft models, oral administration of XL147 results in dose-dependent inhibition of phosphorylation of AKT, p70S6K, and S6 with a duration of action of at least 24 hours. Repeat-dose administration of XL147 results in significant tumor growth inhibition in multiple human xenograft models in nude mice. Administration of XL147 in combination with chemotherapeutic agents results in antitumor activity in xenograft models that is enhanced over that observed with the corresponding single agents. PMID:25637314

  12. 1,10-Phenanthroline promotes copper complexes into tumor cells and induces apoptosis by inhibiting the proteasome activity.

    PubMed

    Zhang, Zhen; Bi, Caifeng; Schmitt, Sara M; Fan, Yuhua; Dong, Lili; Zuo, Jian; Dou, Q Ping

    2012-12-01

    Indole-3-acetic acid and indole-3-propionic acid, two potent natural plant growth hormones, have attracted attention as promising prodrugs in cancer therapy. Copper is known to be a cofactor essential for tumor angiogenesis. We have previously reported that taurine, L-glutamine, and quinoline-2-carboxaldehyde Schiff base copper complexes inhibit cell proliferation and proteasome activity in human cancer cells. In the current study, we synthesized two types of copper complexes, dinuclear complexes and ternary complexes, to investigate whether a certain structure could easily carry copper into cancer cells and consequently inhibit tumor proteasome activity and induce apoptosis. We observed that ternary complexes binding with 1,10-phenanthroline are more potent proteasome inhibitors and apoptosis inducers than dinuclear complexes in PC-3 human prostate cancer cells. Furthermore, the ternary complexes potently inhibit proteasome activity before induction of apoptosis in MDA-MB-231 human breast cancer cells, but not in nontumorigenic MCF-10A cells. Our results suggest that copper complexes binding with 1,10-phenanthroline as the third ligand could serve as potent, selective proteasome inhibitors and apoptosis inducers in tumor cells, and that the ternary complexes may be good potential anticancer drugs. PMID:23053530

  13. Antibody-mediated neutralization of autocrine Gas6 inhibits the growth of pancreatic ductal adenocarcinoma tumors in vivo.

    PubMed

    Moody, Gordon; Belmontes, Brian; Masterman, Stephanie; Wang, Wei; King, Chadwick; Murawsky, Chris; Tsuruda, Trace; Liu, Shuying; Radinsky, Robert; Beltran, Pedro J

    2016-09-15

    Gas6 and its receptors Axl, Mer and Tyro-3 (TAM) are highly expressed in human malignancy suggesting that signaling through this axis may be tumor-promoting. In pancreatic ductal adenocarcinoma (PDAC), Gas6 and the TAM receptor Axl are frequently co-expressed and their co-expression correlates with poor survival. A strategy was devised to generate fully human neutralizing antibodies against Gas6 using XenoMouse® technology. Hybridoma supernatants were selected based on their ability to inhibit Gas6 binding to the receptor Axl and block Gas6-induced Axl phosphorylation in human cells. Two purified antibodies isolated from the screened hybridomas, GMAB1 and GMAB2, displayed optimal cellular potency which was comparable to that of the soluble extracellular domain of the receptor Axl (Axl-Fc). In vivo characterization of GMAB1 was conducted using a pharmacodynamic assay that measured inhibition of Gas6-induced Akt activation in the mouse spleen. Treatment of mice with a single dose (100-1000 µg) of GMAB1 led to greater than 90% inhibition of Gas6-induced phosphorylated Akt (pAkt) for up to 72 hr. Based on the target coverage observed in the PD assay, the efficacy of GMAB1 was tested against human pancreatic adenocarcinoma xenografts. At doses of 50 µg and 150 µg, twice weekly, GMAB1 was able to inhibit 55% and 76% of tumor growth, respectively (p < 0.001 for both treatments vs. control Ig). When combined with gemcitabine, GMAB1 significantly inhibited tumor growth compared to either agent alone (p < 0.001). Together, the data suggest that Gas6 neutralization may be important as a potential strategy for the treatment of PDAC. PMID:27170265

  14. RAS/MAPK Activation Drives Resistance to Smo Inhibition, Metastasis, and Tumor Evolution in Shh Pathway-Dependent Tumors.

    PubMed

    Zhao, Xuesong; Ponomaryov, Tatyana; Ornell, Kimberly J; Zhou, Pengcheng; Dabral, Sukriti K; Pak, Ekaterina; Li, Wei; Atwood, Scott X; Whitson, Ramon J; Chang, Anne Lynn S; Li, Jiang; Oro, Anthony E; Chan, Jennifer A; Kelleher, Joseph F; Segal, Rosalind A

    2015-09-01

    Aberrant Shh signaling promotes tumor growth in diverse cancers. The importance of Shh signaling is particularly evident in medulloblastoma and basal cell carcinoma (BCC), where inhibitors targeting the Shh pathway component Smoothened (Smo) show great therapeutic promise. However, the emergence of drug resistance limits long-term efficacy, and the mechanisms of resistance remain poorly understood. Using new medulloblastoma models, we identify two distinct paradigms of resistance to Smo inhibition. Sufu mutations lead to maintenance of the Shh pathway in the presence of Smo inhibitors. Alternatively activation of the RAS-MAPK pathway circumvents Shh pathway dependency, drives tumor growth, and enhances metastatic behavior. Strikingly, in BCC patients treated with Smo inhibitor, squamous cell cancers with RAS/MAPK activation emerged from the antecedent BCC tumors. Together, these findings reveal a critical role of the RAS-MAPK pathway in drug resistance and tumor evolution of Shh pathway-dependent tumors. PMID:26130651

  15. RAS/MAPK activation drives resistance to Smo inhibition, metastasis and tumor evolution in Shh pathway-dependent tumors

    PubMed Central

    Zhao, Xuesong; Ponomaryov, Tatyana; Ornell, Kimberly J.; Zhou, Pengcheng; Dabral, Sukriti K.; Pak, Ekaterina; Li, Wei; Atwood, Scott X.; Whitson, Ramon J.; Chang, Anne Lynn S.; Li, Jiang; Oro, Anthony E.; Chan, Jennifer A.; Kelleher, Joseph F.; Segal, Rosalind A.

    2015-01-01

    Aberrant Shh signaling promotes tumor growth in diverse cancers. The importance of Shh signaling is particularly evident in medulloblastoma and basal cell carcinoma (BCC), where inhibitors targeting the Shh pathway component Smoothened (Smo) show great therapeutic promise. However, the emergence of drug resistance limits long-term efficacy and the mechanisms of resistance remain poorly understood. Using new medulloblastoma models, we identify two distinct paradigms of resistance to Smo inhibition. Sufu mutations lead to maintenance of the Shh pathway in the presence of Smo inhibitors. Alternatively activation of the RAS/MAPK pathway circumvents Shh pathway-dependency, drives tumor growth and enhances metastatic behavior. Strikingly, in BCC patients treated with Smo inhibitor, squamous cell cancers with RAS/MAPK activation emerged from the antecedent BCC tumors. Together these findings reveal a critical role of RAS/MAPK pathway in drug resistance and tumor evolution of Shh pathway-dependent tumors. PMID:26130651

  16. Aspirin delays mesothelioma growth by inhibiting HMGB1-mediated tumor progression

    PubMed Central

    Yang, H; Pellegrini, L; Napolitano, A; Giorgi, C; Jube, S; Preti, A; Jennings, C J; De Marchis, F; Flores, E G; Larson, D; Pagano, I; Tanji, M; Powers, A; Kanodia, S; Gaudino, G; Pastorino, S; Pass, H I; Pinton, P; Bianchi, M E; Carbone, M

    2015-01-01

    High-mobility group box 1 (HMGB1) is an inflammatory molecule that has a critical role in the initiation and progression of malignant mesothelioma (MM). Aspirin (acetylsalicylic acid, ASA) is the most widely used nonsteroidal anti-inflammatory drug that reduces the incidence, metastatic potential and mortality of many inflammation-induced cancers. We hypothesized that ASA may exert anticancer properties in MM by abrogating the carcinogenic effects of HMGB1. Using HMGB1-secreting and -non-secreting human MM cell lines, we determined whether aspirin inhibited the hallmarks of HMGB1-induced MM cell growth in vitro and in vivo. Our data demonstrated that ASA and its metabolite, salicylic acid (SA), inhibit motility, migration, invasion and anchorage-independent colony formation of MM cells via a novel HMGB1-mediated mechanism. ASA/SA, at serum concentrations comparable to those achieved in humans taking therapeutic doses of aspirin, and BoxA, a specific inhibitor of HMGB1, markedly reduced MM growth in xenograft mice and significantly improved survival of treated animals. The effects of ASA and BoxA were cyclooxygenase-2 independent and were not additive, consistent with both acting via inhibition of HMGB1 activity. Our findings provide a rationale for the well documented, yet poorly understood antitumorigenic activity of aspirin, which we show proceeds via HMGB1 inhibition. Moreover, the use of BoxA appears to allow a more efficient HMGB1 targeting while eluding the known gastrointestinal side effects of ASA. Our findings are directly relevant to MM. Given the emerging importance of HMGB1 and its tumor-promoting functions in many cancer types, and of aspirin in cancer prevention and therapy, our investigation is poised to provide broadly applicable information. PMID:26068794

  17. Aspirin delays mesothelioma growth by inhibiting HMGB1-mediated tumor progression.

    PubMed

    Yang, H; Pellegrini, L; Napolitano, A; Giorgi, C; Jube, S; Preti, A; Jennings, C J; De Marchis, F; Flores, E G; Larson, D; Pagano, I; Tanji, M; Powers, A; Kanodia, S; Gaudino, G; Pastorino, S; Pass, H I; Pinton, P; Bianchi, M E; Carbone, M

    2015-01-01

    High-mobility group box 1 (HMGB1) is an inflammatory molecule that has a critical role in the initiation and progression of malignant mesothelioma (MM). Aspirin (acetylsalicylic acid, ASA) is the most widely used nonsteroidal anti-inflammatory drug that reduces the incidence, metastatic potential and mortality of many inflammation-induced cancers. We hypothesized that ASA may exert anticancer properties in MM by abrogating the carcinogenic effects of HMGB1. Using HMGB1-secreting and -non-secreting human MM cell lines, we determined whether aspirin inhibited the hallmarks of HMGB1-induced MM cell growth in vitro and in vivo. Our data demonstrated that ASA and its metabolite, salicylic acid (SA), inhibit motility, migration, invasion and anchorage-independent colony formation of MM cells via a novel HMGB1-mediated mechanism. ASA/SA, at serum concentrations comparable to those achieved in humans taking therapeutic doses of aspirin, and BoxA, a specific inhibitor of HMGB1, markedly reduced MM growth in xenograft mice and significantly improved survival of treated animals. The effects of ASA and BoxA were cyclooxygenase-2 independent and were not additive, consistent with both acting via inhibition of HMGB1 activity. Our findings provide a rationale for the well documented, yet poorly understood antitumorigenic activity of aspirin, which we show proceeds via HMGB1 inhibition. Moreover, the use of BoxA appears to allow a more efficient HMGB1 targeting while eluding the known gastrointestinal side effects of ASA. Our findings are directly relevant to MM. Given the emerging importance of HMGB1 and its tumor-promoting functions in many cancer types, and of aspirin in cancer prevention and therapy, our investigation is poised to provide broadly applicable information. PMID:26068794

  18. Inhibition of Nucleotide Synthesis Targets Brain Tumor Stem Cells in a Subset of Glioblastoma.

    PubMed

    Laks, Dan R; Ta, Lisa; Crisman, Thomas J; Gao, Fuying; Coppola, Giovanni; Radu, Caius G; Nathanson, David A; Kornblum, Harley I

    2016-06-01

    Inhibition of both the de novo (DNP) and salvage (NSP) pathways of nucleoside synthesis has been demonstrated to impair leukemia cells. We endeavored to determine whether this approach would be efficacious in glioblastoma. To diminish nucleoside biosynthesis, we utilized compound DI-39, which selectively targets NSP, in combination with thymidine (dT), which selectively targets DNP. We employed in vitro and ex vivo models to determine the effects of pretreatment with dT + DI-39 on brain tumor stem cells (BTSC). Here, we demonstrate that this combinatorial therapy elicits a differential response across a spectrum of human patient-derived glioblastoma cultures. As determined by apoptotic markers, most cultures were relatively resistant to treatment, although a subset was highly sensitive. Sensitivity was unrelated to S-phase delay and to DNA damage induced by treatment. Bioinformatics analysis indicated that response across cultures was associated with the transcription factor PAX3 (associated with resistance) and with canonical pathways, including the nucleotide excision repair pathway, PTEN (associated with resistance), PI3K/AKT (associated with sensitivity), and ErbB2-ErbB3. Our in vitro assays demonstrated that, in sensitive cultures, clonal sphere formation was reduced upon removal from pretreatment. In contrast, in a resistant culture, clonal sphere formation was slightly increased upon removal from pretreatment. Moreover, in an intracranial xenograft model, pretreatment of a sensitive culture caused significantly smaller and fewer tumors. In a resistant culture, tumors were equivalent irrespective of pretreatment. These results indicate that, in the subset of sensitive glioblastoma, BTSCs are targeted by inhibition of pyrimidine synthesis. Mol Cancer Ther; 15(6); 1271-8. ©2016 AACR. PMID:27196770

  19. Absence of tumor growth stimulation in a panel of 16 human tumor cell lines by mistletoe extracts in vitro.

    PubMed

    Maier, Gerhard; Fiebig, Heinz-Herbert

    2002-04-01

    Extracts of Viscum album (mistletoe) are widely used as complementary cancer therapies in Europe. The mistletoe lectins have been identified as the main active principle of mistletoe extracts. They have been shown to exhibit cytotoxic effects as well as immunomodulatory activities. The latter is exemplified by induction of cytokine secretion and increased activity of natural killer cells. Recent reports, however, indicated possible tumor growth stimulation by mistletoe extracts. Therefore, the three aqueous mistletoe extracts (Iscador M special, Iscador Qu special and Iscador P) were evaluated for antiproliferative and/or stimulatory effects in a panel of 16 human tumor cell lines in vitro using a cellular proliferation assay. The results show no evidence of stimulation of tumor growth by any of the three Iscador preparations, comprising central nervous system, gastric, non-small cell lung, mammary, prostate, renal and uterine cancer cell lines, as well as cell lines from hematological malignancies and melanomas. On the contrary, Iscador preparations containing a high lectin concentration (Iscador M special and Iscador Qu special) showed antitumor activity in the mammary cancer cell line MAXF 401NL at the 15 microg/ml dose level with a more than 70% growth inhibition compared to untreated control cells. In addition, a slight antitumor activity (growth inhibition 30-70%) was found in three tumor cell lines for Iscador M special and in seven tumor cell lines for Iscador Qu special, respectively. Iscador P, which contains no mistletoe lectin I, showed no antiproliferative activity. PMID:11984083

  20. Analysis of human tumor associated Thomsen-Friedenreich antigen

    SciTech Connect

    Samuel, J.; Noujaim, A.A.; MacLean, G.D.; Suresh, M.R.; Longenecker, B.M. )

    1990-08-01

    The Thomsen-Friedenrich (TF) antigen is a precursor structure of MN blood group antigens and is also expressed by about 90% of human carcinomas. The immunodominant group of TF antigen (beta-galactosyl(1-3)-alpha-N-acetylglactosamine) is present in cryptic form in normal RBC and is revealed by neuraminidase treatment. A murine monoclonal antibody (Mab 49H.8) developed against neuraminidase treated human RBC was reactive against a variety of human tumors. We have characterized the human tumor associated TF antigen detected by this antibody from a human transitional bladder carcinoma cell line (647V), a human colon adenocarcinoma cell line (LS174T), and a pleural effusion fluid of a breast adenocarcinoma patient (PE 89). A heterologous sandwich radioimmunoassay for TF antigen was developed using Mab 49H.8 as the catcher and 125I-peanut agglutinin as the probe. Detergent extracts of 647V and LS174T cells, media conditioned by culturing these cells, and PE 89 were shown to contain the antigen by this assay. The specificity of the antigen capture by Mab 49H.8 in this assay was demonstrated by its selective inhibition by nitrophenyl-beta-D-galactoside, phenyl-beta-D-galactoside, and a TF hapten. Preliminary studies on TF antigen in serum samples using this assay showed that about 53.7% of the carcinoma samples contained an antigen concentration greater than 200 units/ml whereas for 90.9% of the normal samples the antigen concentration was below 200 units/ml. These studies demonstrated that the TF antigen is shed by the tumor cells both in vitro and in vivo. The TF antigen was sensitive to treatment with alkali (0.1 M NaOH for 5 h at 37 degrees C) and periodate (10 mM sodium periodate for 1 h at room temperature), was resistant to acidic pH (50 mM acetate buffer, pH 4.5, for 5 h at 37 degrees C), and could be extracted with perchloric acid.

  1. Human tumor antigens identified with monoclonal antibodies

    SciTech Connect

    AlSedairy, S.T.

    1987-01-01

    MoAbLc1 (IgM) and MoAbLc2 (IgG/sub 2a/) were produced against human lung carcinoma cell line (ChaGo). Lc1 recognizes a approx. = 330-kd/approx. = 310-kd glycoprotein complexes, and Lc2 recognizes a approx. = 60-kd/approx. = 47-kd protein complex. With a panel of cell lines of different tissue origin, Lc1 showed a more restricted reactivity to ChaGo; it cross-reacted with another lung carcinoma cell line (SK-Lc-2) and two breast carcinoma cell lines, but failed to react with cell lines of fetal lung, of colon, esophageal, prostate, stomach, and ovarian carcinomas, of B and T lymphoblastoid cells, neuroblastomas, glioblastoma, astrocytoma, and human peripheral blood lymphocytes. New and improved methods were developed for the production of indium-111-labeled MoAbs for tumor imaging. To facilitate the application of bicyclic anhydride diethylenetriaminepentaacetic acid (BADTPA) to In-111 labeling of antibodies, we have modified the original method by using C-14-labeled BADTPA, which allows precise quantitation of DTPA molecules incorporated. A new heterobifunctional reagent, 2,6-dioxo-N-(carboxyl)morpholine (DCM) was synthesized for chelating In-111 to MoAbs, and demonstrated higher retention of immunoreactivity of the labeled antibody.

  2. Inhibition of peritoneal dissemination of tumor cells by cationized catalase in mice.

    PubMed

    Hyoudou, Kenji; Nishikawa, Makiya; Kobayashi, Yuki; Mukai, Sakiko; Ikemura, Mai; Kuramoto, Yukari; Yamashita, Fumiyoshi; Hashida, Mitsuru

    2007-05-14

    To inhibit peritoneal dissemination of tumor cells by destroying hydrogen peroxide, ethylenediamine-conjugated catalase (ED-catalase), a cationized derivative, was injected into the peritoneal cavity of mice. ED-catalase had about a 6-fold longer retention time within the cavity than unmodified catalase. Peritoneal dissemination was evaluated after intraperitoneal inoculation of B16-BL6/Luc, a melanoma clone stably expressing firefly luciferase, by measuring luciferase activity. An intraperitoneal injection of ED-catalase just before tumor inoculation significantly reduced the number of tumor cells in peritoneal organs. Catalase was less effective, confirming the importance of the retention of the enzyme within the cavity for the inhibition. ED-catalase injected 3 days after tumor inoculation was also effective in inhibiting tumor growth. A real-time quantitative PCR analysis revealed that ED-catalase significantly suppressed the expression of intercellular adhesion molecule-1. Daily dosing of ED-catalase for 7 days significantly prolonged the survival of tumor-bearing mice. These findings indicate that ED-catalase, which is retained for a long time within the peritoneal cavity, is highly effective in inhibiting the adhesion and proliferation of peritoneally disseminated tumor cells, and in increasing the survival of tumor-bearing mice. PMID:17382424

  3. Direct endothelial junction restoration results in significant tumor vascular normalization and metastasis inhibition in mice

    PubMed Central

    Agrawal, Vijayendra; Maharjan, Sony; Kim, Kyeojin; Kim, Nam-Jung; Son, Jimin; Lee, Keunho; Choi, Hyun-Jung; Rho, Seung-Sik; Ahn, Sunjoo; Won, Moo-Ho; Ha, Sang-Jun; Koh, Gou Young; Kim, Young-Myeong; Suh, Young-Ger; Kwon, Young-Guen

    2014-01-01

    Tumor blood vessels are leaky and immature, which causes inadequate blood supply to tumor tissues resulting in hypoxic microenvironment and promotes metastasis. Here we have explored tumor vessel modulating activity of Sac-1004, a recently developed molecule in our lab, which directly potentiates VE-cadherin-mediated endothelial cell junction. Sac-1004 could enhance vascular junction integrity in tumor vessels and thereby inhibit vascular leakage and enhance vascular perfusion. Improved perfusion enabled Sac-1004 to have synergistic anti-tumor effect on cisplatin-mediated apoptosis of tumor cells. Interestingly, characteristics of normalized blood vessels namely reduced hypoxia, improved pericyte coverage and decreased basement membrane thickness were readily observed in tumors treated with Sac-1004. Remarkably, Sac-1004 was also able to inhibit lung and lymph node metastasis in MMTV and B16BL6 tumor models. This was in correlation with a reduction in epithelial-to-mesenchymal transition of tumor cells with considerable diminution in expression of related transcription factors. Moreover, cancer stem cell population dropped substantially in Sac-1004 treated tumor tissues. Taken together, our results showed that direct restoration of vascular junction could be a significant strategy to induce normalization of tumor blood vessels and reduce metastasis. PMID:24811731

  4. Inhibition of metabotropic glutamate receptor 1 suppresses tumor growth and angiogenesis in experimental non-small cell lung cancer.

    PubMed

    Xia, Hui; Zhao, Ying-Nan; Yu, Chang-Hai; Zhao, Yun-Long; Liu, Yang

    2016-07-15

    Metabotropic glutamate receptor 1 (mGlu1 receptor) is expressed in many cancer cell types as compared to normal counterparts underscoring its potential role in tumor behavior. The aim of present study was to test the role of mGlu1 receptor in experimental non-small cell lung cancer (NSCLC). First, protein expression of mGlu1 receptor was higher in human NSCLC cell lines, including both adenocarcinoma and squamous carcinoma subtypes, when compared to normal bronchial epithelial cells. Inhibition of mGlu1 receptor by BAY36-7620 (an mGlu1 receptor-specific inhibitor) inhibited tumor growth and prolonged survival of mice with tumors of A549 or H1299. Treatment with BAY36-7620 suppressed AKT phosphorylation in A549 tumors and pre-treatment with BAY36-7620 blocked the L-quisqualate (a potent mGlu1 receptor agonist)-induced AKT phosphorylation in A549 cells. Treatment with BAY36-7620 reduced cellular proliferation of A549 cells. Treatment with BAY36-7620 enhanced cleaved PARP levels and reduced protein expression of bcl-2, HIF-1α, and VEGF. In contrast, treatment with L-quisqualate reduced cleaved PARP levels and enhanced protein expression of bcl-2, HIF-1α, VEGF, and IL-8, which was reversed by co-incubation with MK2206 (an AKT inhibitor). Pre-treatment with BAY36-7620 blocked the VEGF-induced AKT phosphorylation in HUVECs. Treatment of HUVECs with L-quisqualate resulted in enhancement of capillary tube formation, which was reversed by co-incubation with MK2206. Furthermore, mGlu1 receptor knockdown suppressed tumor growth and prolonged survival of mice with tumors of A549 or H1299. Collectively, inhibition of mGlu1 receptor suppressed tumor growth and angiogenesis in experimental NSCLC. PMID:27132814

  5. Does nutrition support stimulate tumor growth in humans?

    PubMed

    Bossola, Maurizio; Pacelli, Fabio; Rosa, Fausto; Tortorelli, Antonio; Doglietto, Giovan Battista

    2011-04-01

    Many studies have been conducted to ascertain if nutrition support (NS), either as parenteral nutrition (PN) or enteral nutrition (EN), stimulates tumor growth and causes cancer progression, but after almost 30 years, the question remains at least in part unresolved. In this study, previous studies were reviewed to evaluate the effect of NS on tumor growth, tumor proliferation, tumor apoptosis, and cancer-related survival in humans. MEDLINE and PubMed were searched using combinations of the following keywords: PN, EN, tumor growth, tumor proliferation, tumor apoptosis, arginine, ω-3 fatty acids, and glutamine. Unfortunately, the effect of nutrition support on tumor growth has been assessed only in terms of tumor proliferation, whereas the interferences on tumor apoptosis have never been determined. Overall, the results seem conflicting and inconclusive. Similarly, it remains unknown if PN or EN enriched with specific nutrients such as arginine, ω-3 fatty acids, and glutamine can affect tumor growth in humans. It is hoped that further studies will elucidate if NS with conventional or specific nutrients stimulates tumor proliferation, interferes with tumor apoptosis, and causes cancer progression. PMID:21447771

  6. CysLT1R Antagonists Inhibit Tumor Growth in a Xenograft Model of Colon Cancer

    PubMed Central

    Savari, Sayeh; Liu, Minghui; Zhang, Yuan; Sime, Wondossen; Sjölander, Anita

    2013-01-01

    The expression of the inflammatory G-protein coupled receptor CysLT1R has been shown to be upregulated in colon cancer patients and associated with poor prognosis. The present study investigated the correlation between CysLT1R and colon cancer development in vivo using CysLT1R antagonists (ZM198,615 or Montelukast) and the nude mouse xenograft model. Two drug administration regimens were established. The first regimen was established to investigate the importance of CysLT1R in tumor initiation. Nude mice were inoculated with 50 µM CysLT1R antagonist-pretreated HCT-116 colon cancer cells and received continued treatment (5 mg/kg/day, intraperitoneally). The second regimen aimed to address the role of CysLT1R in tumor progression. Nude mice were inoculated with non-pretreated HCT-116 cells and did not receive CysLT1R antagonist treatment until recordable tumor appearance. Both regimens resulted in significantly reduced tumor size, attributed to changes in proliferation and apoptosis as determined by reduced Ki-67 levels and increased levels of p21WAF/Cip1 (P<0.01), cleaved caspase 3, and the caspase-cleaved product of cytokeratin 18. Decreased levels of VEGF (P<0.01) and reduced vessel size (P<0.05) were also observed, the latter only in the ZM198,615-pretreatment group. Furthermore, we performed a series of in vitro studies using the colon cancer cell line HCT-116 and CysLT1R antagonists. In addition to significant reductions in cell proliferation, adhesion and colony formation, we observed induction of cell cycle arrest and apoptosis in a dose-dependent manner. The ability of Montelukast to inhibit growth of human colon cancer xenograft was further validated by using two additional colon cancer cell lines, SW-480 and HT-29. Our results demonstrate that CysLT1R antagonists inhibit growth of colon cancer xenografts primarily by reducing proliferation and inducing apoptosis of the tumor cells. PMID:24039952

  7. Identification of internalizing human single chain antibodies targeting brain tumor sphere cells

    PubMed Central

    Zhu, Xiaodong; Bidlingmaier, Scott; Hashizume, Rintaro; James, C. David; Berger, Mitchel S.; Liu, Bin

    2010-01-01

    Glioblastoma multiforme (GBM) is the most common and aggressive form of primary brain tumor and there is no curative treatment to date. Resistance to conventional therapies and tumor recurrence pose major challenges to treatment and management of this disease, and therefore new therapeutic strategies need to be developed. Previous studies by other investigators have shown that a subpopulation of GBM cells can grow as neurosphere-like cells when cultured in restrictive media, and exhibit enhanced tumor initiating ability and resistance to therapy. We report here the identification of internalizing human single chain antibodies (scFvs) targeting GBM tumor sphere cells. We selected a large naive phage antibody display library on the glycosylation-dependent CD133 epitope-positive subpopulation of GBM cells grown as tumor spheres and identified internalizing scFvs that target tumor sphere cells broadly, as well as scFvs that target the CD133 positive subpopulation. These scFvs were found to be efficiently internalized by GBM tumor sphere cells. One scFv GC4 inhibited self-renewal of GBM tumor sphere cells in vitro. We have further developed a full-length human IgG1 based on this scFv and found that it potently inhibits proliferation of GBM tumor sphere cells and GBM cells grown in regular non-selective media. Taken together, these results show that internalizing human scFvs targeting brain tumor sphere cells can be readily identified from a phage antibody display library, which could be useful for further development of novel therapies that target subpopulations of GBM cells to combat recurrence and resistance to treatment. PMID:20587664

  8. Novel Midkine Inhibitor iMDK Inhibits Tumor Growth and Angiogenesis in Oral Squamous Cell Carcinoma.

    PubMed

    Masui, Masanori; Okui, Tatsuo; Shimo, Tsuyoshi; Takabatake, Kiyofumi; Fukazawa, Takuya; Matsumoto, Kenichi; Kurio, Naito; Ibaragi, Soichiro; Naomoto, Yoshio; Nagatsuka, Hitoshi; Sasaki, Akira

    2016-06-01

    Midkine is a heparin-binding growth factor highly expressed in various human malignant tumors. However, its role in the growth of oral squamous cell carcinoma is not well understood. In this study, we analyzed the antitumor effect of a novel midkine inhibitor (iMDK) against oral squamous cell carcinoma. Administration of iMDK induced a robust antitumor response and suppressed cluster of differentiation 31 (CD31) expression in oral squamous cell carcinoma HSC-2 cells and SAS cells xenograft models. iMDK inhibited the proliferation of these cells dose-dependently, as well as the expression of midkine and phospho-extracellular signal-regulated kinase in HSC-2 and SAS cells. Moreover, iMDK significantly inhibited vascular endothelial growth factor and induced tube growth of human umbilical vein endothelial cells in a dose-dependent fashion. These findings suggest that midkine is critically involved in oral squamous cell carcinoma and iMDK can be effectively used for the treatment of oral squamous cell carcinoma. PMID:27272788

  9. Moxifloxacin increases anti-tumor and anti-angiogenic activity of irinotecan in human xenograft tumors.

    PubMed

    Reuveni, Debby; Halperin, Drora; Fabian, Ina; Tsarfaty, Galia; Askenasy, Nadir; Shalit, Itamar

    2010-04-15

    Camptothecins (CPTs) are topoisomerase I inhibitors chemotherapeutic agents used in combination chemotherapy. We showed previously that combination of moxifloxacin (MXF) and CPT induced inhibitory effects on topoisomerase I activity, on proliferation of HT-29 cells in vitro and enhanced apoptosis, compared to CPT alone. Analysis of secretion of the pro-angiogenic factors IL-8 and VEGF showed significant reduction by MXF. Using a murine model of human colon carcinoma xenograft, we compared the effects of MXF/CPT in vitro to MXF/irinotecan combination in vivo. We show that the MXF/CPT inhibitory effects observed in vitro are reflected in the inhibition of the progressive growth of HT-29 cells implanted in SCID mice. Using caliper measurements, Doppler ultrasonography, image analyses and immunohistochemistry of nuclear proteins (Ki-67) and vascular endothelial cells (CD-31) we show that addition of MXF (45mg/kg) to a relatively ineffective dose of irinotecan (20mg/kg), results in a 50% and 30% decrease, respectively, in tumor size and a decrease in Ki-67 staining. Power Doppler Ultrasound showed a significant, pronounced decrease in the number of blood vessels, as did CD-31 staining, indicating decreased blood flow in tumors in mice treated with MXF alone or MXF/irinotecan compared to irinotecan. These results suggest that the combination of MXF/irinotecan may result in enhanced anti-neoplastic/anti-angiogenic activity. PMID:20025849

  10. Inhibition of melanocortin 1 receptor slows melanoma growth, reduces tumor heterogeneity and increases survival.

    PubMed

    Kansal, Rita G; McCravy, Matthew S; Basham, Jacob H; Earl, Joshua A; McMurray, Stacy L; Starner, Chelsey J; Whitt, Michael A; Albritton, Lorraine M

    2016-05-01

    Melanoma risk is increased in patients with mutations of melanocortin 1 receptor (MC1R) yet the basis for the increased risk remains unknown. Here we report in vivo evidence supporting a critical role for MC1R in regulating melanoma tumor growth and determining overall survival time. Inhibition of MC1R by its physiologically relevant competitive inhibitor, agouti signaling protein (ASIP), reduced melanin synthesis and morphological heterogeneity in murine B16-F10 melanoma cells. In the lungs of syngeneic C57BL/6 mice, mCherry-marked, ASIP-secreting lung tumors inhibited MC1R on neighboring tumors lacking ASIP in a dose dependent manner as evidenced by a proportional loss of pigment in tumors from mice injected with 1:1, 3:1 and 4:1 mixtures of parental B16-F10 to ASIP-expressing tumor cells. ASIP-expressing B16-F10 cells formed poorly pigmented tumors in vivo that correlated with a 20% longer median survival than those bearing parental B16-F10 tumors (p=0.0005). Mice injected with 1:1 mixtures also showed survival benefit (p=0.0054), whereas injection of a 4:1 mixture showed no significant difference in survival. The longer survival time of mice bearing ASIP-expressing tumors correlated with a significantly slower growth rate than parental B16-F10 tumors as judged by quantification of numbers of tumors and total tumor load (p=0.0325), as well as a more homogeneous size and morphology of ASIP-expressing lung tumors. We conclude that MC1R plays an important role in regulating melanoma growth and morphology. Persistent inhibition of MC1R provided a significant survival advantage resulting in part from slower tumor growth, establishing MC1R as a compelling new molecular target for metastatic melanoma. PMID:27028866

  11. Antigen targeting to dendritic cells combined with transient regulatory T cell inhibition results in long-term tumor regression

    PubMed Central

    Unger, Wendy WJ; Mayer, Christian T; Engels, Steef; Hesse, Christina; Perdicchio, Maurizio; Puttur, Franz; Streng-Ouwehand, Ingeborg; Litjens, Manja; Kalay, Hakan; Berod, Luciana; Sparwasser, Tim; van Kooyk, Yvette

    2014-01-01

    Therapeutic vaccinations against cancer are still largely ineffective. Major caveats are inefficient delivery of tumor antigens to dendritic cells (DCs) and excessive immune suppression by Foxp3+ regulatory T cells (Tregs), resulting in defective T cell priming and failure to induce tumor regression. To circumvent these problems we evaluated a novel combinatorial therapeutic strategy. We show that tumor antigen targeting to DC-SIGN in humanized hSIGN mice via glycans or specific antibodies induces superior T cell priming. Next, this targeted therapy was combined with transient Foxp3+ Treg depletion employing hSIGNxDEREG mice. While Treg depletion alone slightly delayed B16-OVA melanoma growth, only the combination therapy instigated long-term tumor regression in a substantial fraction of mice. This novel strategy resulted in optimal generation of antigen-specific activated CD8+ T cells which accumulated in regressing tumors. Notably, Treg depletion also allowed the local appearance of effector T cells specific for endogenous B16 antigens. This indicates that antitumor immune responses can be broadened by therapies aimed at controlling Tregs in tumor environments. Thus, transient inhibition of Treg-mediated immune suppression potentiates DC targeted antigen vaccination and tumor-specific immunity. PMID:26405564

  12. Salinomycin efficiency assessment in non-tumor (HB4a) and tumor (MCF-7) human breast cells.

    PubMed

    Niwa, Andressa Megumi; D Epiro, Gláucia Fernanda Rocha; Marques, Lilian Areal; Semprebon, Simone Cristine; Sartori, Daniele; Ribeiro, Lúcia Regina; Mantovani, Mário Sérgio

    2016-06-01

    The search for anticancer drugs has led researchers to study salinomycin, an ionophore antibiotic that selectively destroys cancer stem cells. In this study, salinomycin was assessed in two human cell lines, a breast adenocarcinoma (MCF-7) and a non-tumor breast cell line (HB4a), to verify its selective action against tumor cells. Real-time assessment of cell proliferation showed that HB4a cells are more resistant to salinomycin than MCF-7 tumor cell line, and these data were confirmed in a cytotoxicity assay. The half maximal inhibitory concentration (IC50) values show the increased sensitivity of MCF-7 cells to salinomycin. In the comet assay, only MCF-7 cells showed the induction of DNA damage. Flow cytometric analysis showed that cell death by apoptosis/necrosis was only induced in the MCF-7 cells. The increased expression of GADD45A and CDKN1A genes was observed in all cell lines. Decreased expression of CCNA2 and CCNB1 genes occurred only in tumor cells, suggesting G2/M cell cycle arrest. Consequently, cell death was activated in tumor cells through strong inhibition of the antiapoptotic genes BCL-2, BCL-XL, and BIRC5 genes in MCF-7 cells. These data demonstrate the selectivity of salinomycin in killing human mammary tumor cells. The cell death observed only in MCF-7 tumor cells was confirmed by gene expression analysis, where there was downregulation of antiapoptotic genes. These data contribute to clarifying the mechanism of action of salinomycin as a promising antitumor drug and, for the first time, we observed the higher resistance of HB4a non-tumor breast cells to salinomycin. PMID:26932586

  13. Mucosal Imprinting of Vaccine-Induced CD8+ T Cells Is Crucial to Inhibit the Growth of Mucosal Tumors

    PubMed Central

    Sandoval, Federico; Bureau, Michel-Francis; Freyburger, Ludovic; Clement, Olivier; Marcheteau, Elie; Gey, Alain; Fraisse, Guillaume; Bouguin, Cécilia; Merillon, Nathalie; Dransart, Estelle; Tran, Thi; Quintin-Colonna, Françoise; Autret, Gwennhael; Thiebaud, Marine; Suleman, Muhammad; Riffault, Sabine; Wu, Tzyy-Choou; Launay, Odile; Danel, Claire; Taieb, Julien; Richardson, Jennifer; Zitvogel, Laurence; Fridman, Wolf H.; Johannes, Ludger; Tartour, Eric

    2014-01-01

    Although many human cancers are located in mucosal sites, most cancer vaccines are tested against subcutaneous tumors in preclinical models. We therefore wondered whether mucosa-specific homing instructions to the immune system might influence mucosal tumor outgrowth. We showed that the growth of orthotopic head and neck or lung cancers was inhibited when a cancer vaccine was delivered by the intranasal mucosal route but not the intramuscular route. This antitumor effect was dependent on CD8+ T cells. Indeed, only intranasal vaccination elicited mucosal-specific CD8+ T cells expressing the mucosal integrin CD49a. Blockade of CD49a decreased intratumoral CD8+ T cell infiltration and the efficacy of cancer vaccine on mucosal tumor. We then showed that after intranasal vaccination, dendritic cells from lung parenchyma, but not those from spleen, induced the expression of CD49a on cocultured specific CD8+ T cells. Tumor-infiltrating lymphocytes from human mucosal lung cancer also expressed CD49a, which supports the relevance and possible extrapolation of these results in humans. We thus identified a link between the route of vaccination and the induction of a mucosal homing program on induced CD8+ T cells that controlled their trafficking. Immunization route directly affected the efficacy of the cancer vaccine to control mucosal tumors. PMID:23408053

  14. Establishment and Characterization of a Human Neuroendocrine Tumor Xenograft.

    PubMed

    Yang, Zhaoying; Zhang, Le; Serra, Stefano; Law, Calvin; Wei, Alice; Stockley, Tracy L; Ezzat, Shereen; Asa, Sylvia L

    2016-06-01

    Neuroendocrine tumors (NETs) are increasing in incidence yet the cause of these tumors remains unknown. Familial associations have shed light on the genetic basis of some of these tumors, but sporadic tumors seem to have primarily epigenetic dysregulation. The rarity of cell lines and animal models has been a barrier to studies of treatment modalities. We set out to develop a xenograft model of gastrointestinal NETs. Primary human NETs were collected at the time of surgery under sterile conditions and xenografted into the flanks of immunodeficient mice. Tumor growth was measured and when tumors reached 1500 mm(3), they were excised and half was re-xenografted through multiple generations. The other half was bisected; a part was frozen and a part was fixed for morphologic and immunohistochemical characterization as well as molecular validation of fidelity of a successful xenograft. Of 106 human NETs, seven were successfully engrafted of which only one tumor was successfully propagated for eight passages. Two years later, the tumor retains its neuroendocrine features and similarity to the original primary human tumor. It has retained expression of keratin as well as chromogranin A reactivity. The establishment of a NET xenograft provides a model for further study of the biological behavior of these tumors and can be used to examine the in vivo effects of various medical and targeted radiotherapeutic agents on tumor growth. PMID:27067082

  15. Temozolomide/PLGA microparticles plus vatalanib inhibits tumor growth and angiogenesis in an orthotopic glioma model.

    PubMed

    Zhang, Yu-Hui; Yue, Zhi-Jian; Zhang, He; Tang, Gu-Sheng; Wang, Yang; Liu, Jian-Min

    2010-11-01

    Temozolomide (TM) has anti-tumor activity in patients with malignant glioma. Implantable poly (D,L-lactide-co-glycolide) (PLGA) microparticles of TM (TM-MS) have been developed, enhancing the cytotoxicity of TM to Glioma C6 cells. Vatalanib, as anti-angiogenic agent, has also shown anti-tumor activity with malignant gliomas. We examined the combined effects of TM-MS and vatalanib in a rat orthotopic glioma model and found TM-MS offered a greater tumor inhibition than TM, and combination treatment with both of them improved the survival time versus single agent therapy. The combination treatment also demonstrated an inhibition to rat glioma tumors, a significant decrease in cell proliferation, an increase in apoptosis, and a lower microvessel density within the glioma tumors. The results suggest that TM-MS can more effectively inhibit tumor than TM, and combination treatment with TM-MS and vatalanib inhibits tumor growth and angiogenesis and may prove to be a promising therapy for malignant gliomas. PMID:20816959

  16. MMGZ01, an anti-DLL4 monoclonal antibody, promotes nonfunctional vessels and inhibits breast tumor growth.

    PubMed

    Xu, Zhuobin; Wang, Zegen; Jia, Xuelian; Wang, Luxuan; Chen, Zhiguo; Wang, Shijing; Wang, Min; Zhang, Juan; Wu, Min

    2016-03-01

    Increasing evidence suggests that DLL4 (Delta-like 4)-Notch signaling plays a critical role in cell fate determination and differentiation in tissues. Blocking DLL4-Notch signaling results in inhibition of tumor growth, which is associated with increased nonfunctional vessels and poor perfusion in the tumor. We successfully generated a human DLL4 monoclonal antibody MMGZ01 that binds specifically to DLL4 to disrupt the interaction between DLL4 and Notch1. MMGZ01 showed high affinity to DLL4 to inhibit the DLL4-mediated human umbilical vein endothelial cell (HUVEC) phenotype. Furthermore, MMGZ01 stimulated HUVEC vessel sprouting and tubule formation in vitro. In addition, MMGZ01 had a pronounced effect in promoting immature vessels and reduced breast cancer cell growth in vivo. Finally, MMGZ01 treatment inhibited the proliferation of breast cancer cells, induced tumor cell apoptosis, suppressed mammosphere formation, decreased CD44(+)/CD24(-) cell population, and reduced epithelial mesenchymal transition (EMT). These findings suggest that antagonism of the DLL4-Notch signaling pathway might provide a potential therapeutic approach for breast cancer treatment. PMID:26739060

  17. APOBEC3 Inhibition of Mouse Mammary Tumor Virus Infection: the Role of Cytidine Deamination versus Inhibition of Reverse Transcription

    PubMed Central

    MacMillan, Alyssa L.; Kohli, Rahul M.

    2013-01-01

    The apolipoprotein B editing complex 3 (APOBEC3) family of proteins is a group of intrinsic antiviral factors active against a number of retroviral pathogens, including HIV in humans and mouse mammary tumor virus (MMTV) in mice. APOBEC3 restricts its viral targets through cytidine deamination of viral DNA during reverse transcription or via deaminase-independent means. Here, we used virions from the mammary tissue of MMTV-infected inbred wild-type mice with different allelic APOBEC3 variants (APOBEC3BALB and APOBEC3BL/6) and knockout mice to determine whether cytidine deamination was important for APOBEC3's anti-MMTV activity. First, using anti-murine APOBEC3 antiserum, we showed that both APOBEC3 allelic variants are packaged into the cores of milk-borne virions produced in vivo. Next, using an in vitro deamination assay, we determined that virion-packaged APOBEC3 retains its deamination activity and that allelic differences in APOBEC3 affect the sequence specificity. In spite of this in vitro activity, cytidine deamination by virion-packaged APOBEC3 of MMTV early reverse transcription DNA occurred only at low levels. Instead, the major means by which in vivo virion-packaged APOBEC3 restricted virus was through inhibition of early reverse transcription in both cell-free virions and in vitro infection assays. Moreover, the different wild-type alleles varied in their ability to inhibit this step. Our data suggest that while APOBEC3-mediated cytidine deamination of MMTV may occur, it is not the major means by which APOBEC3 restricts MMTV infection in vivo. This may reflect the long-term coexistence of MMTV and APOBEC3 in mice. PMID:23449789

  18. Efficient inhibition of tumor angiogenesis and growth by a synthetic peptide blocking S100A4-methionine aminopeptidase 2 interaction

    PubMed Central

    Ochiya, Takahiro; Takenaga, Keizo; Asagiri, Masataka; Nakano, Kazumi; Satoh, Hitoshi; Watanabe, Toshiki; Imajoh-Ohmi, Shinobu; Endo, Hideya

    2015-01-01

    The prometastatic calcium-binding protein, S100A4, is expressed in endothelial cells, and its downregulation markedly suppresses tumor angiogenesis in a xenograft cancer model. Given that endothelial S100A4 can be a molecular target for inhibiting tumor angiogenesis, we addressed here whether synthetic peptide capable of blocking S100A4-effector protein interaction could be a novel antiangiogenic agent. To examine this hypothesis, we focused on the S100A4-binding domain of methionine aminopeptidase 2, an effector protein, which plays a role in endothelial cell growth. Overexpression of the domain in mouse endothelial MSS31 cells reduced DNA synthesis, and the corresponding synthetic peptide (named NBD) indeed interacted with S100A4 and inhibited capillary formation in vitro and new blood vessel formation in vivo. Intriguingly, a single intra-tumor administration of the NBD peptide in human prostate cancer xenografts significantly reduced vascularity, resulting in tumor regression. Mechanistically, the NBD peptide enhanced assembly of nonmuscle myosin IIA filaments along with Ser1943 phosphorylation, stimulated formation of focal adhesions without phosphorylation of focal adhesion kinase, and provoked G1/S arrest of the cell cycle. Altogether, the NBD peptide is a potent inhibitor for tumor angiogenesis, and is the first example of an anticancer peptide drug developed on the basis of an endothelial S100A4-targeted strategy. PMID:26029719

  19. Efficient inhibition of tumor angiogenesis and growth by a synthetic peptide blocking S100A4-methionine aminopeptidase 2 interaction.

    PubMed

    Ochiya, Takahiro; Takenaga, Keizo; Asagiri, Masataka; Nakano, Kazumi; Satoh, Hitoshi; Watanabe, Toshiki; Imajoh-Ohmi, Shinobu; Endo, Hideya

    2015-01-01

    The prometastatic calcium-binding protein, S100A4, is expressed in endothelial cells, and its downregulation markedly suppresses tumor angiogenesis in a xenograft cancer model. Given that endothelial S100A4 can be a molecular target for inhibiting tumor angiogenesis, we addressed here whether synthetic peptide capable of blocking S100A4-effector protein interaction could be a novel antiangiogenic agent. To examine this hypothesis, we focused on the S100A4-binding domain of methionine aminopeptidase 2, an effector protein, which plays a role in endothelial cell growth. Overexpression of the domain in mouse endothelial MSS31 cells reduced DNA synthesis, and the corresponding synthetic peptide (named NBD) indeed interacted with S100A4 and inhibited capillary formation in vitro and new blood vessel formation in vivo. Intriguingly, a single intra-tumor administration of the NBD peptide in human prostate cancer xenografts significantly reduced vascularity, resulting in tumor regression. Mechanistically, the NBD peptide enhanced assembly of nonmuscle myosin IIA filaments along with Ser1943 phosphorylation, stimulated formation of focal adhesions without phosphorylation of focal adhesion kinase, and provoked G1/S arrest of the cell cycle. Altogether, the NBD peptide is a potent inhibitor for tumor angiogenesis, and is the first example of an anticancer peptide drug developed on the basis of an endothelial S100A4-targeted strategy. PMID:26029719

  20. Polymalic acid nanobioconjugate for simultaneous inhibition of tumor growth and immunostimulation in HER2/neu-positive breast cancer✩

    PubMed Central

    Ding, Hui; Helguera, Gustavo; Rodríguez, José A.; Markman, Janet; Luria-Pérez, Rosendo; Gangalum, Pallavi; Portilla-Arias, Jose; Inoue, Satoshi; Daniels-Wells, Tracy R.; Black, Keith; Holler, Eggehard; Penichet, Manuel L.; Ljubimova, Julia Y.

    2013-01-01

    Breast cancer remains the second leading cause of cancer death among women in the United States. The breast cancer prognosis is particularly poor in case of tumors overexpressing the oncoprotein HER2/neu. A new nanobioconjugate of the Polycefin family of anti-cancer drugs based on biodegradable and non-toxic polymalic acid (PMLA) was engineered for a multi-pronged attack on HER2/neu-positive breast cancer cells. An antibody cytokine fusion protein consisting of the immunostimulatory cytokine interleukin-2 (IL-2) genetically fused to an antibody specific for human HER2/neu [anti-HER2/neu IgG3-(IL-2)] was covalently attached to the PMLA backbone to target HER2/neu expressing tumors and ensuring the delivery of IL-2 to the tumor microenvironment. Antisense oligonucleotides (AON) were conjugated to the nanodrug to inhibit the expression of vascular tumor protein laminin-411 in order to block tumor angiogenesis. It is shown that the nanobioconjugate was capable of specifically binding human HER2/neu and retaining the biological activity of IL-2. We also showed the uptake of the nanobioconjugate by HER2/neu-positive breast cancer cells and enhanced tumor targeting in vivo. In addition, the nanobioconjugate was capable of eliciting anti-tumor activity in immunocompetent mice bearing D2F2/E2 murine mammary tumors that express human HER2/neu. Both IgG1 and IgG2a levels were significantly increased in animals treated with the PMLA-fusion nanobioconjugate compared to animals treated with the antibody–cytokine fusion protein alone or control animals, indicative of the induction of a humoral (TH2) and cell-mediated (TH1) immune responses. Animal survival in vivo was significantly longer after treatment with leading nanobioconjugate with fusion [anti-HER2/neu IgG3-(IL-2)] antibody, p < 0.05. The combination of these molecules on a single polymeric platform is expected to act through direct elimination of cancer cells, inhibition of tumor angiogenesis, and orchestration of a

  1. Dystrophin is a tumor suppressor in human cancers with myogenic programs.

    PubMed

    Wang, Yuexiang; Marino-Enriquez, Adrian; Bennett, Richard R; Zhu, Meijun; Shen, Yiping; Eilers, Grant; Lee, Jen-Chieh; Henze, Joern; Fletcher, Benjamin S; Gu, Zhizhan; Fox, Edward A; Antonescu, Cristina R; Fletcher, Christopher D M; Guo, Xiangqian; Raut, Chandrajit P; Demetri, George D; van de Rijn, Matt; Ordog, Tamas; Kunkel, Louis M; Fletcher, Jonathan A

    2014-06-01

    Many common human mesenchymal tumors, including gastrointestinal stromal tumor (GIST), rhabdomyosarcoma (RMS) and leiomyosarcoma (LMS), feature myogenic differentiation. Here we report that intragenic deletion of the dystrophin-encoding and muscular dystrophy-associated DMD gene is a frequent mechanism by which myogenic tumors progress to high-grade, lethal sarcomas. Dystrophin is expressed in the non-neoplastic and benign counterparts of GIST, RMS and LMS tumors, and DMD deletions inactivate larger dystrophin isoforms, including 427-kDa dystrophin, while preserving the expression of an essential 71-kDa isoform. Dystrophin inhibits myogenic sarcoma cell migration, invasion, anchorage independence and invadopodia formation, and dystrophin inactivation was found in 96%, 100% and 62% of metastatic GIST, embryonal RMS and LMS samples, respectively. These findings validate dystrophin as a tumor suppressor and likely anti-metastatic factor, suggesting that therapies in development for muscular dystrophies may also have relevance in the treatment of cancer. PMID:24793134

  2. Nitric Oxide Synthase Inhibition by NG-Nitro-l-Arginine Methyl Ester Inhibits Tumor-Induced Angiogenesis in Mammary Tumors

    PubMed Central

    Jadeski, Lorraine C.; Lala, Peeyush K.

    1999-01-01

    Using a murine breast cancer model, we earlier found a positive correlation between the expression of nitric oxide synthase (NOS) and tumor progression; treatment with inhibitors of NOS, NG-methyl-l-arginine (NMMA) and NG-nitro-l-arginine methyl ester (L-NAME), had antitumor and antimetastatic effects that were partly attributed to reduced tumor cell invasiveness. In the present study, we used a novel in vivo model of tumor angiogenesis using subcutaneous implants of tumor cells suspended in growth factor-reduced Matrigel to examine the angiogenic role of NO in a highly metastatic murine mammary adenocarcinoma cell line. This cell line, C3L5, expresses endothelial (e) NOS in vitro and in vivo, and inducible (i) NOS in vitro on stimulation with lipopolysaccharide and interferon-γ. Female C3H/HeJ mice received subcutaneous implants of growth factor-reduced Matrigel inclusive of C3L5 cells on one side, and on the contralateral side, Matrigel alone; L-NAME and D-NAME (inactive enantiomer) were subsequently administered for 14 days using osmotic minipumps. Immediately after sacrifice, implants were removed and processed for immunolocalization of eNOS and iNOS proteins, and measurement of angiogenesis. Neovascularization was quantified in sections stained with Masson’s trichrome or immunostained for the endothelial cell specific CD31 antigen. While most tumor cells and endothelial cells expressed immunoreactive eNOS protein, iNOS was localized in endothelial cells and some macrophages within the tumor-inclusive implants. Measurable angiogenesis occurred only in implants containing tumor cells. Irrespective of the method of quantification used, tumor-induced neovascularization was significantly reduced in L-NAME-treated mice relative to those treated with D-NAME. The quantity of stromal tissue was lower, but the quantity of necrotic tissue higher in L-NAME relative to D-NAME-treated animals. The total mass of viable tissue (ie, stroma and tumor cells) was lower in L

  3. Conditional ablation of Ikkb inhibits melanoma tumor development in mice

    PubMed Central

    Yang, Jinming; Splittgerber, Ryan; Yull, Fiona E.; Kantrow, Sara; Ayers, Gregory D.; Karin, Michael; Richmond, Ann

    2010-01-01

    Several lines of evidence suggest that tumor cells show elevated activity of the NF-κB transcription factor, a phenomenon often resulting from constitutive activity of IκB kinase β (IKKβ). However, others have found that loss of NF-κB activity or IKKβ is tumor promoting. The role of NF-κB in tumor progression is therefore controversial and varies with tumor type. We sought to more extensively investigate the role IKKβ in melanoma tumor development by specifically disrupting Ikkb in melanocytes in an established mouse model of spontaneous melanoma, whereby HRasV12 is expressed in a melanocyte-specific, doxycycline-inducible manner in mice null for the gene encoding the tumor suppressor inhibitor cyclin-dependent kinase 4/alternative reading frame (Ink4a/Arf). Our results show that Ink4a/Arf–/– mice with melanocyte-specific deletion of Ikkb were protected from HRasV12-initiated melanoma only when p53 was expressed. This protection was accompanied by cell cycle arrest, with reduced cyclin-dependent kinase 2 (Cdk2), Cdk4, Aurora kinase A, and Aurora kinase B expression. Increased p53-mediated apoptosis was also observed, with decreased expression of the antiapoptotic proteins Bcl2 and survivin. Enhanced stabilization of p53 involved increased phosphorylation at Ser15 and reduced phosphorylation of double minute 2 (Mdm2) at Ser166. Together, our findings provide genetic and mechanistic evidence that mutant HRas initiation of tumorigenesis requires Ikkβ-mediated NF-κB activity. PMID:20530876

  4. Cinnamon extract induces tumor cell death through inhibition of NFκB and AP1

    PubMed Central

    2010-01-01

    Background Cinnamomum cassia bark is the outer skin of an evergreen tall tree belonging to the family Lauraceae containing several active components such as essential oils (cinnamic aldehyde and cinnamyl aldehyde), tannin, mucus and carbohydrate. They have various biological functions including anti-oxidant, anti-microbial, anti-inflammation, anti-diabetic and anti-tumor activity. Previously, we have reported that anti-cancer effect of cinnamon extracts is associated with modulation of angiogenesis and effector function of CD8+ T cells. In this study, we further identified that anti-tumor effect of cinnamon extracts is also link with enhanced pro-apoptotic activity by inhibiting the activities NFκB and AP1 in mouse melanoma model. Methods Water soluble cinnamon extract was obtained and quality of cinnamon extract was evaluated by HPLC (High Performance Liquid Chromatography) analysis. In this study, we tested anti-tumor activity and elucidated action mechanism of cinnamon extract using various types of tumor cell lines including lymphoma, melanoma, cervix cancer and colorectal cancer in vitro and in vivo mouse melanoma model. Results Cinnamon extract strongly inhibited tumor cell proliferation in vitro and induced active cell death of tumor cells by up-regulating pro-apoptotic molecules while inhibiting NFκB and AP1 activity and their target genes such as Bcl-2, BcL-xL and survivin. Oral administration of cinnamon extract in melanoma transplantation model significantly inhibited tumor growth with the same mechanism of action observed in vitro. Conclusion Our study suggests that anti-tumor effect of cinnamon extracts is directly linked with enhanced pro-apoptotic activity and inhibition of NFκB and AP1 activities and their target genes in vitro and in vivo mouse melanoma model. Hence, further elucidation of active components of cinnamon extract could lead to development of potent anti-tumor agent or complementary and alternative medicine for the treatment of

  5. Inhibition of Mouse Breast Tumor-Initiating Cells by Calcitriol and Dietary Vitamin D.

    PubMed

    Jeong, Youngtae; Swami, Srilatha; Krishnan, Aruna V; Williams, Jasmaine D; Martin, Shanique; Horst, Ronald L; Albertelli, Megan A; Feldman, Brian J; Feldman, David; Diehn, Maximilian

    2015-08-01

    The anticancer actions of vitamin D and its hormonally active form, calcitriol, have been extensively documented in clinical and preclinical studies. However, the mechanisms underlying these actions have not been completely elucidated. Here, we examined the effect of dietary vitamin D and calcitriol on mouse breast tumor-initiating cells (TICs, also known as cancer stem cells). We focused on MMTV-Wnt1 mammary tumors, for which markers for isolating TICs have previously been validated. We confirmed that these tumors expressed functional vitamin D receptors and estrogen receptors (ER) and exhibited calcitriol-induced molecular responses including ER downregulation. Following orthotopic implantation of MMTV-Wnt1 mammary tumor cells into mice, calcitriol injections or a vitamin D-supplemented diet caused a striking delay in tumor appearance and growth, whereas a vitamin D-deficient diet accelerated tumor appearance and growth. Calcitriol inhibited TIC tumor spheroid formation in a dose-dependent manner in primary cultures and inhibited TIC self-renewal in secondary passages. A combination of calcitriol and ionizing radiation inhibited spheroid formation more than either treatment alone. Further, calcitriol significantly decreased TIC frequency as evaluated by in vivo limiting dilution analyses. Calcitriol inhibition of TIC spheroid formation could be overcome by the overexpression of β-catenin, suggesting that the inhibition of Wnt/β-catenin pathway is an important mechanism mediating the TIC inhibitory activity of calcitriol in this tumor model. Our findings indicate that vitamin D compounds target breast TICs reducing tumor-initiating activity. Our data also suggest that combining vitamin D compounds with standard therapies may enhance anticancer activity and improve therapeutic outcomes. PMID:25934710

  6. Blockade of MUC1 expression by glycerol guaiacolate inhibits proliferation of human breast cancer cells.

    PubMed

    Smith, J S; Colon, J; Madero-Visbal, R; Isley, B; Konduri, S D; Baker, C H

    2010-10-01

    We sought to determine whether administration of glycerol guaiacolate at an optimal biological dose inhibits human breast cancer cell growth. Human breast cancer MCF-7 and ZR-75-1 cells were treated with glycerol guaiacolate and the therapeutic efficacy and biological activity of this drug was investigated on breast cancer cell growth. MCF-7 cells were injected into the mammary fat pad of overectamized female athymic nude mice. Ten days later, animals were treated with daily intraperitoneal injections of glycerol guaiacolate for six weeks. Tumor size and volume was monitored and immunohistochemistry analysis on MUC1, p21 and ki-67 was performed. Glycerol guaiacolate decreased breast cancer cell growth in a dose-dependent manner, decreased cell migration, and caused G1 cell cycle arrest. Our results demonstrate that glycerol guaiacolate inhibits MUC1 protein and mRNA expression levels and significantly increased p21 expression in human breast cancer cells as well as induced PARP cleavage. Similarly, glycerol guaiacolate inhibited breast tumor growth in vivo as well as enhanced p21 expression and decreased breast tumor cell proliferation (ki-67 expression). Collectively, our results demonstrate that glycerol guaiacolate decreased MUC1 expression and enhanced cell growth inhibition by inducing p21 expression in breast cancer cells. These findings suggest that glycerol guaiacolate may provide a novel and effective approach for the treatment of human breast cancer. PMID:21184665

  7. Gefitinib inhibits the cross-talk between mesenchymal stem cells and prostate cancer cells leading to tumor cell proliferation and inhibition of docetaxel activity.

    PubMed

    Borghese, Cinzia; Cattaruzza, Lara; Pivetta, Eliana; Normanno, Nicola; De Luca, Antonella; Mazzucato, Mario; Celegato, Marta; Colombatti, Alfonso; Aldinucci, Donatella

    2013-05-01

    Increasing evidence suggests that bone marrow derived mesenchymal stem cells (BM-MSCs) are recruited into the stroma of developing tumors where they contribute to progression by enhancing tumor growth and metastasis, or by inducing anticancer-drug resistance. Prostate cancer cells secrete ligands of epidermal growth factor receptor (EGFR) and EGFR signaling could play an important role in the cross-talk between mesenchymal stem cells and prostate cancer cells. In this study, we showed that treatment of human primary MSCs with conditioned medium (CM) derived from the bone metastatic PC3 carcinoma cells (PC3-CM) resulted in: a significant activation of EGFR; increased proliferation; increased osteoblastic but decreased adipocitic differentiation; inhibition of senescence induced by serum starvation; increased CCL5 secretion. These activities were significantly inhibited in the presence of the EGFR tyrosine kinase inhibitor gefitinib. PC3-CM directly inhibited osteoclastogenesis as well as the ability of osteoblasts to induce osteoclast differentiation. The increased MSCs migration by PC3-CM and PC3 cells was partially mediated by CCL5. MSC-CM increased the formation of colonies by PC3 cells and inhibited the anti-proliferative activity of Docetaxel. Activation of EGFR expressed on MSCs by PC3-CM enhanced their capability to increase PC3 cells proliferation and to inhibit Docetaxel activity. These findings, by showing that the tumor-promoting interactions between PC3 cells and MSCs are mediated, at least in part, by EGFR, suggest a novel application of the EGFR-tyrosine kinase inhibitors in the treatment of prostate cancer. PMID:23192362

  8. Oxidative stress inhibits distant metastasis by human melanoma cells

    PubMed Central

    Piskounova, Elena; Agathocleous, Michalis; Murphy, Malea M.; Hu, Zeping; Huddlestun, Sara E.; Zhao, Zhiyu; Leitch, A. Marilyn; Johnson, Timothy M.; DeBerardinis, Ralph J.; Morrison, Sean J.

    2015-01-01

    Solid cancer cells commonly enter the blood and disseminate systemically but are highly inefficient at forming distant metastases for poorly understood reasons. We studied human melanomas that differed in their metastasis histories in patients and in their capacity to metastasize in NSG mice. All melanomas had high frequencies of cells that formed subcutaneous tumours, but much lower percentages of cells that formed tumours after intravenous or intrasplenic transplantation, particularly among inefficient metastasizers. Melanoma cells in the blood and visceral organs experienced oxidative stress not observed in established subcutaneous tumours. Successfully metastasizing melanomas underwent reversible metabolic changes during metastasis that increased their capacity to withstand oxidative stress, including increased dependence upon NADPH-generating enzymes in the folate pathway. Anti-oxidants promoted distant metastasis in NSG mice. Folate pathway inhibition using low-dose methotrexate, ALDH1L2 knockdown, or MTHFD1 knockdown inhibited distant metastasis without significantly affecting the growth of subcutaneous tumors in the same mice. Oxidative stress thus limits distant metastasis by melanoma cells in vivo. PMID:26466563

  9. Lovastatin and tumor necrosis factor-alpha exhibit potentiated antitumor effects against Ha-ras-transformed murine tumor via inhibition of tumor-induced angiogenesis.

    PubMed

    Feleszko, W; Bałkowiec, E Z; Sieberth, E; Marczak, M; Dabrowska, A; Giermasz, A; Czajka, A; Jakóbisiak, M

    1999-05-17

    Lovastatin, a drug commonly used in the treatment of hypercholesterolemia, has previously been reported to exert potentiated antitumor activity when combined with either tumor necrosis factor-alpha (TNF-alpha), cisplatin or doxorubicin in a melanoma model in mice. Since lovastatin interferes with the function of ras oncogene-encoded (Ras) proteins, we have investigated the antitumor activity of lovastatin and TNF-alpha using a Ha-ras-transformed murine tumor model. In in vitro studies, lovastatin inhibited the growth of cells transformed with Ha-ras oncogene (Ras-3T3 and HBL100-ras cells) more effectively than control NIH-3T3 and HBL100-neo cells. In in vivo experiments, the Ras-3T3 tumor demonstrated significantly increased sensitivity to combined treatment with both lovastatin (50 mg/kg) and TNF-alpha (1 microg/day) compared with either agent alone. Combined treatment with both agents also resulted in greater inhibition of blood-vessel formation. Ras-3T3 tumor cells produced increased amounts of vascular endothelial growth factor (VEGF) and lovastatin effectively suppressed VEGF production by these cells. Our results suggest that lovastatin increases antitumor activity of TNF-alpha against tumor cells transformed with v-Ha-ras oncogene via inhibition of tumor-induced blood-vessel formation. PMID:10225445

  10. A comparative study of peanut agglutinin and amaranthin binding to human urinary bladder tumor glycoproteins.

    PubMed

    Langkilde, N C; Orntoft, T F

    1995-01-01

    The reactivity of two T-antigen specific lectins, Amaranthin (ACA) and Peanut Agglutinin (PNA), was compared by immunohistochemical staining of serial sections of human bladder tumors and by Western Blot analysis of glycoproteins extracted from human bladder tumors prior to and after sialic acid removal. In low grade tumors ACA reacted prior to neuraminidase treatment. PNA on the other hand only showed positive reaction in these tumors after neuraminidase treatment. The two lectins showed identical staining patterns after neuraminidase treatment in tumors. In Western blottings both lectins detected a 28 kD glycoprotein. PNA also reacted with several other bands after neuraminidase treatment. The reactivity of ACA was not enhanced after neuraminidase treatment. In monosaccharide inhibition tests ACA- and PNA-binding to different T-antigens was most efficiently inhibited by GalNAc and Gal respectively. PNA binding was also inhibited by Glc, GlcNAc and GalNAc at higher concentrations, while the binding of ACA was only scarcely affected by Glc, GlcNAc and Gal. PMID:8578258

  11. Ursolic acid inhibits tumor angiogenesis and induces apoptosis through mitochondrial-dependent pathway in Ehrlich ascites carcinoma tumor.

    PubMed

    Saraswati, Sarita; Agrawal, S S; Alhaider, Abdulqader A

    2013-11-25

    Ursolic acid (UA) is a pentacyclic triterpene naturally occurring in many plant foods. In the present study, we investigated anti-cancer activity of UA in vivo in Ehrlich ascites carcinoma (EAC) tumor. 15 × 10(6) EAC cells were implanted intraperitoneally (i.p., ascitic tumor) and subcutaneous (s.c., solid tumor) in Swiss albino mice. Mice with established tumors received UA i.p. at 25, 50 and 100mg/kg bw for 14 d in ascitic and 100mg/kg bw in solid tumor for 30 d. On day 15, blood samples were collected for hematological assessment of hemoglobin (Hb%), RBCs, WBCs and PCV. Tumor volume, cell viability, angiogenic, anti-angiogenic, anti-inflammatory factors and antioxidant parameters were determined. Immunohistochemistry analysis for VEGF, iNOS, CD31, caspase-3 and Bax were also performed. UA significantly inhibited tumor growth, cell viability, in both ascites and solid tumor model in vivo (p<0.001). The anti-angiogenic effects were accompanied with decreased VEGF, iNOS, TNF-α and increased IL-12 levels. UA at 100mg/kg bw dose significantly increased SOD and CAT activity (p<0.01). GSH and TBARS were increased as compared to control group (p<0.001). Furthermore, UA increased total RBCs, WBCs as well as Hb% significantly (p<0.05) compared to cyclophosphamide (CP). Histopathological examination of tumor cells in the treated group demonstrated signs of apoptosis with chromatin condensation and cell shrinkage. Decreased peritoneal angiogenesis showed the anti-angiogenic potential. UA downregulated VEGF & iNOS expression whereas bax and caspase-3 expressions were upregulated suggesting drug induced tumor cell apoptosis through activating the pro-apoptotic bcl-2 family and caspase-3 and downregulation of VEGF. The present study sheds light on the potent antitumor property of the UA and can be extended further to develop therapeutic protocols for treatment of cancer. PMID:24051192

  12. Extract of Vernonia condensata, Inhibits Tumor Progression and Improves Survival of Tumor-allograft Bearing Mouse.

    PubMed

    Thomas, Elizabeth; Gopalakrishnan, Vidya; Somasagara, Ranganatha R; Choudhary, Bibha; Raghavan, Sathees C

    2016-01-01

    Medicinal plants are considered as one of the ideal sources for cancer therapy due to their bioactive contents and low toxicity to humans. Vernonia genus is one of the common medicinal plants, which has wide spread usage in food and medicine. However, there are limited studies to explore its anticancer properties. In the current study, we have used Vernonia condensata, to explore its anticancer activity using various approaches. Here, we show that extract prepared from Vernonia condensata (VCE) exhibits cytotoxic properties against various cancer cells in a dose- and time-dependent manner. Interestingly, when treated with VCE, there was no significant cytotoxicity in peripheral blood mononuclear cells (PBMCs). Flow cytometry analysis revealed that although VCE induced cell death, arrest was not observed. VCE treatment led to disruption of mitochondrial membrane potential in a concentration dependent manner resulting in activation of apoptosis culminating in cell death. Immunoblotting studies revealed that VCE activated intrinsic pathway of apoptosis. More importantly, VCE treatment resulted in tumor regression leading to significant enhancement in life span in treated mice, without showing any detectable side effects. Therefore, for the first time our study reveals the potential of extract from Vernonia condensata to be used as an anticancer agent. PMID:27009490

  13. Extract of Vernonia condensata, Inhibits Tumor Progression and Improves Survival of Tumor-allograft Bearing Mouse

    PubMed Central

    Thomas, Elizabeth; Gopalakrishnan, Vidya; Somasagara, Ranganatha R.; Choudhary, Bibha; Raghavan, Sathees C.

    2016-01-01

    Medicinal plants are considered as one of the ideal sources for cancer therapy due to their bioactive contents and low toxicity to humans. Vernonia genus is one of the common medicinal plants, which has wide spread usage in food and medicine. However, there are limited studies to explore its anticancer properties. In the current study, we have used Vernonia condensata, to explore its anticancer activity using various approaches. Here, we show that extract prepared from Vernonia condensata (VCE) exhibits cytotoxic properties against various cancer cells in a dose- and time-dependent manner. Interestingly, when treated with VCE, there was no significant cytotoxicity in peripheral blood mononuclear cells (PBMCs). Flow cytometry analysis revealed that although VCE induced cell death, arrest was not observed. VCE treatment led to disruption of mitochondrial membrane potential in a concentration dependent manner resulting in activation of apoptosis culminating in cell death. Immunoblotting studies revealed that VCE activated intrinsic pathway of apoptosis. More importantly, VCE treatment resulted in tumor regression leading to significant enhancement in life span in treated mice, without showing any detectable side effects. Therefore, for the first time our study reveals the potential of extract from Vernonia condensata to be used as an anticancer agent. PMID:27009490

  14. Heme oxygenase-1 promotes tumor progression and metastasis of colorectal carcinoma cells by inhibiting antitumor immunity

    PubMed Central

    Seo, Geom Seog; Jiang, Wen-Yi; Chi, Jin Hua; Jin, Hao; Park, Won-Chul; Sohn, Dong Hwan; Park, Pil-Hoon; Lee, Sung Hee

    2015-01-01

    Heme oxygenase-1 (HO-1) is upregulated in colorectal carcinoma (CRC) cells. However, the role of HO-1 in the metastatic potential of CRC remains to be elucidated. In this study, we investigated the potential of HO-1 to control the antitumor immunity of CRC. Intercellular adhesion molecule-1 (ICAM-1) plays an important role in the immune surveillance system. Hemin-induced HO-1 expression suppressed the expression of ICAM-1 in human CRC cells. HO-1 regulated ICAM-1 expression via tristetraprolin, an mRNA-binding protein, at the posttranscriptional level in CRC cells. The upregulated HO-1 expression in CRC cells markedly decreased the adhesion of peripheral blood mononuclear lymphocytes (PBMLs) to CRC cells and PBML-mediated cytotoxicity against CRC cells. Production of CXCL10, an effector T cell-recruiting chemokine, was significantly reduced by the increased HO-1 expression. The expression of the CXCL10 receptor, CXCR3, decreased significantly in PBMLs that adhered to CRC cells. HO-1 expression correlated negatively, although nonsignificantly, with ICAM-1 and CXCL10 expression in xenograft tumors. Taken together, our data suggest that HO-1 expression is functionally linked to the mediation of tumor progression and metastasis of CRC cells by inhibiting antitumor immunity. PMID:26087182

  15. HEDGEHOG-GLI signaling inhibition suppresses tumor growth in squamous lung cancer

    PubMed Central

    Huang, Lingling; Walter, Vonn; Hayes, D. Neil; Onaitis, Mark

    2014-01-01

    Purpose Lung squamous cell carcinoma (LSCC) currently lacks effective targeted therapies. Previous studies reported overexpression of HEDGEHOG (HH)-GLI signaling components in LSCC. However, they addressed neither the tumor heterogeneity nor the requirement for HH-GLI signaling. Here, we investigated the role of HH-GLI signaling in LSCC, and studied the therapeutic potential of HH-GLI suppression. Experimental Design Gene expression datasets of two independent LSCC patient cohorts were analyzed to study the activation of HH-GLI signaling. Four human LSCC cell lines were examined for HH-GLI signaling components. Cell proliferation and apoptosis were assayed in these cells after blocking the HH-GLI pathway by lentiviral-shRNA knockdown or small molecule inhibitors. Xenografts in immunodeficient mice were used to determine the in vivo efficacy of GLI inhibitor GANT61. Results In both cohorts, activation of HH-GLI signaling was significantly associated with the classical subtype of LSCC. In cell lines, genetic knockdown of SMO produced minor effects on cell survival, while GLI2 knockdown significantly reduced proliferation and induced extensive apoptosis. Consistently, the SMO inhibitor GDC-0449 resulted in limited cytotoxicity in LSCC cells, whereas the GLI inhibitor GANT61 was very effective. Importantly, GANT61 demonstrated specific in vivo anti-tumor activity in xenograft models of GLI-positive cell lines. Conclusion Our studies demonstrate an important role for GLI2 in LSCC, and suggest GLI inhibition as a novel and potent strategy to treat a subset of LSCC patients. PMID:24423612

  16. MiR-122 targets VEGFC in bladder cancer to inhibit tumor growth and angiogenesis

    PubMed Central

    Wang, Yi; Xing, Qing-Fei; Liu, Xiao-Qiang; Guo, Zhan-Jun; Li, Chang-Ying; Sun, Guang

    2016-01-01

    Previous studies indicate that microRNA-122 (miR-122) is down-regulated in several cancer cells and regulates cell apoptosis, proliferation, metastasis, and tumor angiogenesis. However, the mount of miR-122 in bladder cancer and the pivotal molecular mechanisms of miR-122 used to regulate bladder carcinogenesis and angiogenesis remain to be clarified. Here, we reveal that miR-122 expression is down-regulated in human bladder cancer tissues and cell lines. MiR-122 represses vascular endothelial growth factor C (VEGFC) post-transcriptional expression by directly binding to its 3’-UTR. The protein kinase B (AKT) and mammalian target of rapamycin (mTOR), which are the most important downstream molecules of VEGFC, are also decreased in bladder cancer cell after miR-122 overexpression. Furthermore, miR-122 over-expression decreases bladder cancer cell migration, invasion, colony formation in vitro and slow bladder cancer growth and angiogenesis in vivo. Finally, miR-122 sensitizes bladder cancer cells to cisplatin-induced apoptosis. Taken together, these studies suggest that miR-122 serves as a tumor suppressor and down-regulating VEGFC expression, leading to the inhibition of bladder cancer growth and angiogenesis. PMID:27508026

  17. Comparative Epigenomics of Human and Mouse Mammary Tumors

    PubMed Central

    Demircan, Berna; Dyer, Lisa M.; Gerace, Mallory; Lobenhofer, Edward K.; Robertson, Keith D.; Brown, Kevin D.

    2010-01-01

    Gene silencing by aberrant epigenetic chromatin alteration is a well-recognized event contributing to tumorigenesis. While genetically engineered tumor-prone mouse models have proven a powerful tool in understanding many aspects of carcinogenesis, to date few studies have focused on epigenetic alterations in mouse tumors. To uncover epigenetically silenced tumor suppressor genes (TSGs) in mouse mammary tumor cells, we conducted initial genome-wide screening by combining the treatment of cultured cells with the DNA demethylating drug 5-aza-2′-deoxycytidine (5-azadC) and the histone deacetylase inhibitor trichostatin A (TSA) with expression microarray. By conducting this initial screen on EMT6 cells and applying protein function and genomic structure criteria to genes identified as upregulated in response to 5-azadC/TSA, we were able to identify 2 characterized breast cancer TSGs (Timp3 and Rprm) and 4 putative TSGs (Atp1B2, Dusp2, FoxJ1 and Smpd3) silenced in this line. By testing a panel of ten mouse mammary tumor lines, we determined that each of these genes is commonly hypermethylated, albeit with varying frequency. Furthermore, by examining a panel of human breast tumor lines and primary tumors we observed that the human orthologs of ATP1B2, FOXJ1 and SMPD3 are aberrantly hypermethylated in the human disease while DUSP2 was not hypermethylated in primary breast tumors. Finally, we examined hypermethylation of several genes targeted for epigenetic silencing in human breast tumors in our panel of ten mouse mammary tumor lines. We observed that the orthologs of Cdh1, RarB, Gstp1, RassF1 genes were hypermethylated, while neither Dapk1 nor Wif1 were aberrantly methylated in this panel of mouse tumor lines. From this study, we conclude that there is significant, but not absolute, overlap in the epigenome of human and mouse mammary tumors. PMID:18836996

  18. Map2k4 Functions as a Tumor Suppressor in Lung Adenocarcinoma and Inhibits Tumor Cell Invasion by Decreasing Peroxisome Proliferator-Activated Receptor γ2 Expression ▿

    PubMed Central

    Ahn, Young-Ho; Yang, Yanan; Gibbons, Don L.; Creighton, Chad J.; Yang, Fei; Wistuba, Ignacio I.; Lin, Wei; Thilaganathan, Nishan; Alvarez, Cristina A.; Roybal, Jonathon; Goldsmith, Elizabeth J.; Tournier, Cathy; Kurie, Jonathan M.

    2011-01-01

    MAP2K4 encodes a dual-specificity kinase (mitogen-activated protein kinase kinase 4, or MKK4) that is mutated in a variety of human malignancies, but the biochemical properties of the mutant kinases and their roles in tumorigenesis have not been fully elucidated. Here we showed that 8 out of 11 cancer-associated MAP2K4 mutations reduce MKK4 protein stability or impair its kinase activity. On the basis of findings from bioinformatic studies on human cancer cell lines with homozygous MAP2K4 loss, we posited that MKK4 functions as a tumor suppressor in lung adenocarcinomas that develop in mice owing to expression of mutant Kras and Tp53. Conditional Map2k4 inactivation in the bronchial epithelium of mice had no discernible effect alone but increased the multiplicity and accelerated the growth of incipient lung neoplasias induced by oncogenic Kras. MKK4 suppressed the invasion and metastasis of Kras-Tp53-mutant lung adenocarcinoma cells. MKK4 deficiency increased peroxisomal proliferator-activated receptor γ2 (PPARγ2) expression through noncanonical MKK4 substrates, and PPARγ2 enhanced tumor cell invasion. We conclude that Map2k4 functions as a tumor suppressor in lung adenocarcinoma and inhibits tumor cell invasion by decreasing PPARγ2 levels. PMID:21896780

  19. Inhibition of brain tumor cell proliferation by alternating electric fields

    SciTech Connect

    Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi E-mail: radioyoon@korea.ac.kr; Sung, Jiwon; Jeong, Seonghoon; Yoon, Myonggeun E-mail: radioyoon@korea.ac.kr; Koh, Eui Kwan

    2014-11-17

    This study was designed to investigate the mechanism by which electric fields affect cell function, and to determine the optimal conditions for electric field inhibition of cancer cell proliferation. Low-intensity (<2 V/cm) and intermediate-frequency (100–300 kHz) alternating electric fields were applied to glioblastoma cell lines. These electric fields inhibited cell proliferation by inducing cell cycle arrest and abnormal mitosis due to the malformation of microtubules. These effects were significantly dependent on the intensity and frequency of applied electric fields.

  20. Inhibition of tumor-stromal interaction through HGF/Met signaling by valproic acid

    SciTech Connect

    Matsumoto, Yohsuke; Motoki, Takahiro; Kubota, Satoshi; Takigawa, Masaharu; Tsubouchi, Hirohito; Gohda, Eiichi

    2008-02-01

    Hepatocyte growth factor (HGF), which is produced by surrounding stromal cells, including fibroblasts and endothelial cells, has been shown to be a significant factor responsible for cancer cell invasion mediated by tumor-stromal interactions. We found in this study that the anti-tumor agent valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, strongly inhibited tumor-stromal interaction. VPA inhibited HGF production in fibroblasts induced by epidermal growth factor (EGF), platelet-derived growth factor, basic fibroblast growth factor, phorbol 12-myristate 13-acetate (PMA) and prostaglandin E{sub 2} without any appreciable cytotoxic effect. Other HDAC inhibitors, including butyric acid and trichostatin A (TSA), showed similar inhibitory effects on HGF production stimulated by various inducers. Up-regulations of HGF gene expression induced by PMA and EGF were also suppressed by VPA and TSA. Furthermore, VPA significantly inhibited HGF-induced invasion of HepG2 hepatocellular carcinoma cells. VPA, however, did not affect the increases in phosphorylation of MAPK and Akt in HGF-treated HepG2 cells. These results demonstrated that VPA inhibited two critical processes of tumor-stromal interaction, induction of fibroblastic HGF production and HGF-induced invasion of HepG2 cells, and suggest that those activities serve for other anti-tumor mechanisms of VPA besides causing proliferation arrest, differentiation, and/or apoptosis of tumor cells.

  1. PCB126 Inhibits Adipogenesis of Human Preadipocytes

    PubMed Central

    Gadupudi, Gopi; Gourronc, Francoise A.; Ludewig, Gabriele; Robertson, Larry W.; Klingelhutz, Aloysius J.

    2014-01-01

    Emerging evidence indicates that persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), are involved in the development of diabetes. Dysfunctional adipocytes play a significant role in initiating insulin resistance. Preadipocytes make up a large portion of adipose tissue and are necessary for the generation of functional mature adipocytes through adipogenesis. PCB126 is a dioxin-like PCB and a potent aryl hydrocarbon receptor (AhR) agonist. We hypothesized that PCB126 may be involved in the development of diabetes through disruption of adipogenesis. Using a newly developed human preadipocyte cell line called NPAD (Normal PreADipocytes), we found that exposure of preadipocytes to PCB126 resulted in significant reduction in their subsequent ability to fully differentiate into adipocytes, more so than when the cells were exposed to PCB126 during differentiation. Reduction in differentiation by PCB126 was associated with downregulation of transcript levels of a key adipocyte transcription factor, PPARγ, and late adipocyte differentiation genes. An AhR antagonist, CH223191, blocked this effect. These studies indicate that preadipocytes are particularly sensitive to the effects of PCB126 and suggest that AhR activation inhibits PPARγ transcription and subsequent adipogenesis. Our results validate the NPAD cell line as a useful model for studying the effects of POPs on adipogenesis. PMID:25304490

  2. Fulvene-5 potently inhibits NADPH oxidase 4 and blocks the growth of endothelial tumors in mice

    PubMed Central

    Bhandarkar, Sulochana S.; Jaconi, Marisa; Fried, Levi E.; Bonner, Michael Y.; Lefkove, Benjamin; Govindarajan, Baskaran; Perry, Betsy N.; Parhar, Ravi; Mackelfresh, Jamie; Sohn, Allie; Stouffs, Michael; Knaus, Ulla; Yancopoulos, George; Reiss, Yvonne; Benest, Andrew V.; Augustin, Hellmut G.; Arbiser, Jack L.

    2009-01-01

    Hemangiomas are the most common type of tumor in infants. As they are endothelial cell–derived neoplasias, their growth can be regulated by the autocrine-acting Tie2 ligand angiopoietin 2 (Ang2). Using an experimental model of human hemangiomas, in which polyoma middle T–transformed brain endothelial (bEnd) cells are grafted subcutaneously into nude mice, we compared hemangioma growth originating from bEnd cells derived from wild-type, Ang2+/–, and Ang2–/– mice. Surprisingly, Ang2-deficient bEnd cells formed endothelial tumors that grew rapidly and were devoid of the typical cavernous architecture of slow-growing Ang2-expressing hemangiomas, while Ang2+/– cells were greatly impaired in their in vivo growth. Gene array analysis identified a strong downregulation of NADPH oxidase 4 (Nox4) in Ang2+/– cells. Correspondingly, lentiviral silencing of Nox4 in an Ang2-sufficient bEnd cell line decreased Ang2 mRNA levels and greatly impaired hemangioma growth in vivo. Using a structure-based approach, we identified fulvenes as what we believe to be a novel class of Nox inhibitors. We therefore produced and began the initial characterization of fulvenes as potential Nox inhibitors, finding that fulvene-5 efficiently inhibited Nox activity in vitro and potently inhibited hemangioma growth in vivo. In conclusion, the present study establishes Nox4 as a critical regulator of hemangioma growth and identifies fulvenes as a potential class of candidate inhibitor to therapeutically interfere with Nox function. PMID:19620773

  3. Effect of soy isoflavones on the growth of human breast tumors: findings from preclinical studies

    PubMed Central

    Kwon, Youngjoo

    2014-01-01

    Breast cancer is the most common cancer among women worldwide, and many women with breast cancer live more than 5 years after their diagnosis. Breast cancer patients and survivors have a greater interest in taking soy foods and isoflavone supplements. However, the effect of isoflavones on breast cancer remains controversial. Thus, it is critical to determine if and when isoflavones are beneficial or detrimental to breast cancer patients. According to the available preclinical data, high concentrations of isoflavones inhibit the proliferation of breast cancer cells, regardless of their estrogen receptor (ER) status. In comparison, genistein, a major isoflavone, has stimulated tumor growth at low concentrations and mitigated tamoxifen efficacy in ER-positive breast cancer. Studies have indicated that the relative levels of genistein and estrogen at the target site are important to determine the genistein effect on the ER-positive tumor growth. However, studies using ovariectomized mice and subcutaneous xenograft models might not truly reflect estrogen concentrations in human breast tumors. Moreover, it may be an oversimplification that isoflavones stimulate hormone-dependent tumor growth due to their potential estrogenic effect since studies also suggest nonestrogenic anticancer effects of isoflavones and ER-independent anticancer activity of tamoxifen. Therefore, the concentrations of isoflavones and estrogen in human breast tumors should be considered better in future preclinical studies and the parameters that can estimate those levels in breast tumors are required in human clinical/epidemiological investigation. In addition, it will be important to identify the molecular mechanisms that either inhibit or promote the growth of breast cancer cells by soy isoflavones, and use those molecules to evaluate the relevance of the preclinical findings to the human disease and to predict the health effects of isoflavones in human breast tumors. PMID:25493176

  4. Isatin-pyrazole benzenesulfonamide hybrids potently inhibit tumor-associated carbonic anhydrase isoforms IX and XII.

    PubMed

    Ibrahim, Hany S; Abou-Seri, Sahar M; Tanc, Muhammet; Elaasser, Mahmoud M; Abdel-Aziz, Hatem A; Supuran, Claudiu T

    2015-10-20

    New series of benzenesulfonamide derivatives incorporating pyrazole and isatin moieties were prepared using celecoxib as lead molecule. Biological evaluation of the target compounds was performed against the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) and more precisely against the human isoforms hCA I, II (cytosolic), IX and XII (transmembrane, tumor-associated enzymes). Most of the tested compounds efficiently inhibited hCA I, II and IX, with KIs of 2.5-102 nM, being more effective than the reference drug acetazolamide. Compounds 11e, 11f, 16e and 16f were found to inhibit hCA XII with Ki of 3.7, 6.5, 5.4 and 7.2 nM, respectively. Compounds 11e and 16e, with 5-NO2 substitution on the isatin ring, were found to be selective inhibitors of hCA IX and hCA XII. Docking studies revealed that the NO2 group of both compounds participate in interactions with Asp132 within the hCA IX active site, and with residues Lys67 and Asp130 in hCA XII, respectively. PMID:26408817

  5. Pharmacological or genetic inhibition of LDHA reverses tumor progression of pediatric osteosarcoma.

    PubMed

    Gao, Shan; Tu, Dan-Na; Li, Heng; Jiang, Jian-Xin; Cao, Xin; You, Jin-Bin; Zhou, Xiao-Qin

    2016-07-01

    Reprogrammed energy metabolism is an emerging hallmark of cancer. Lactate dehydrogenase A (LDHA), a key enzyme involved in anaerobic glycolysis, is frequently deregulated in human malignancies. However, limited knowledge is known about its roles in the progression of osteosarcoma (OS). In this study, we found that LDHA is commonly upregulated in four OS cell lines compared with the normal osteoblast cells (hFOB1.19). Treatment with FX11, a specific inhibitor of LDHA, significantly reduced LDHA activity, and inhibited cell proliferation and invasive potential in a dose dependent manner. Genetic silencing of LDHA resulted in a decreased lactate level in the culture medium, reduced cell viability and decreased cell invasion ability. Meanwhile, silencing of LDHA also compromised tumorigenesis in vivo. Furthermore, knockdown of LDHA remarkably reduced extracellular acidification rate (ECAR) as well as glucose consumption. In the presence of 2-DG, a glycolysis inhibitor, LDHA-mediated cell proliferation and invasion were completely blocked, indicating the oncogenic activities of LDHA may dependent on Warburg effect. Finally, pharmacological inhibition of c-Myc or HIF1α significantly attenuated LDHA expression. Taken together, upregulated LDHA facilitates tumor progression of OS and might be a potential target for OS treatment. PMID:27261617

  6. Enhancer of zeste homolog 2 silencing inhibits tumor growth and lung metastasis in osteosarcoma

    PubMed Central

    Lv, Yang-Fan; Yan, Guang-Ning; Meng, Gang; Zhang, Xi; Guo, Qiao-Nan

    2015-01-01

    The enhancer of zeste homolog 2 (EZH2) methyltransferase is the catalytic subunit of polycomb repressive complex 2 (PRC2), which acts as a transcription repressor via the trimethylation of lysine 27 of histone 3 (H3K27me3). EZH2 has been recognised as an oncogene in several types of tumors; however, its role in osteosarcoma has not been fully elucidated. Herein, we show that EZH2 silencing inhibits tumor growth and lung metastasis in osteosarcoma by facilitating re-expression of the imprinting gene tumor-suppressing STF cDNA 3 (TSSC3). Our previous study showed that TSSC3 acts as a tumor suppressor in osteosarcoma. In this study, we found that EZH2 was abnormally elevated in osteosarcoma, and its overexpression was associated with poor prognosis in osteosarcoma. Silencing of EZH2 resulted in tumor growth inhibition, apoptosis and chemosensitivity enhancement. Moreover, suppression of EZH2 markedly inhibited tumor growth and lung metastasis in vivo. Furthermore, EZH2 knockdown facilitated the re-expression of TSSC3 by reducing H3K27me3 in the promoter region. Cotransfection with siEZH2 and siTSSC3 could partially reverse the ability of siEZH2 alone. We have demonstrated that EZH2 plays a crucial role in tumor growth and distant metastasis in osteosarcoma; its oncogenic role is related to its regulation of the expression of TSSC3. PMID:26265454

  7. Evaluation of Elephantopus scaber on the inhibition of chemical carcinogenesis and tumor development in mice.

    PubMed

    Geetha, B S; Latha, P G; Remani, P

    2010-03-01

    The effect of the active fraction of Elephantopus scaber L. (Asteraceae) (ES) on skin papillomas induced by 7,12-dimethylbenz(a)anthracene (DMBA) as an initiator and croton oil as promoter was studied in mice. The active fraction of E. scaber (100 mg/kg) on topical application delayed the onset of papilloma formation and reduced the mean number of papillomas and the mean weight of papillomas per mouse. The intraperitoneal administration of the active fraction of E. scaber also had a significant effect on subcutaneous injection of 20-methylcholanthrene (20-MCA)-induced soft tissue sarcomas in mice. It inhibited the incidence of sarcomas and reduced the tumor diameter compared to MCA-treated control animals. The subcutaneous administration of the active fraction of E. scaber significantly inhibited the growth of subcutaneously transplanted DLA and EAC solid tumors, delayed the onset of tumor formation, and increased the life span of tumor bearing mice. The present study thus indicates the tumor inhibitory activity of the active fraction of E. scaber against chemically induced tumors and its ability to inhibit the development of solid tumors. PMID:20645824

  8. Multiwalled Carbon Nanotubes Inhibit Tumor Progression in a Mouse Model.

    PubMed

    García-Hevia, Lorena; Villegas, Juan C; Fernández, Fidel; Casafont, Íñigo; González, Jesús; Valiente, Rafael; Fanarraga, Mónica L

    2016-05-01

    Understanding the molecular mechanisms underlying the biosynthetic interactions between particular nanomaterials with specific cells or proteins opens new alternatives in nanomedicine and nanotoxicology. Multiwalled carbon nanotubes (MWCNTs) have long been explored as drug delivery systems and nanomedicines against cancer. There are high expectations for their use in therapy and diagnosis. These filaments can translocate inside cultured cells and intermingle with the protein nanofilaments of the cytoskeleton, interfering with the biomechanics of cell division mimicking the effect of traditional microtubule-binding anti-cancer drugs such as paclitaxel. Here, it is shown how MWCNTs can trigger significant anti-tumoral effects in vivo, in solid malignant melanomas produced by allograft transplantation. Interestingly, the MWCNT anti-tumoral effects are maintained even in solid melanomas generated from paclitaxel-resistant cells. These findings provide great expectation in the development of groundbreaking adjuvant synthetic microtubule-stabilizing chemotherapies to overcome drug resistance in cancer. PMID:26866927

  9. GSK-3β signaling determines autophagy activation in the breast tumor cell line MCF7 and inclusion formation in the non-tumor cell line MCF10A in response to proteasome inhibition

    PubMed Central

    Gavilán, E; Sánchez-Aguayo, I; Daza, P; Ruano, D

    2013-01-01

    The ubiquitin–proteasome system and the autophagy–lysosome pathway are the two main mechanisms for eukaryotic intracellular protein degradation. Proteasome inhibitors are used for the treatment of some types of cancer, whereas autophagy seems to have a dual role in tumor cell survival and death. However, the relationship between both pathways has not been extensively studied in tumor cells. We have investigated both proteolytic systems in the human epithelial breast non-tumor cell line MCF10A and in the human epithelial breast tumor cell line MCF7. In basal condition, tumor cells showed a lower proteasome function but a higher autophagy activity when compared with MCF10A cells. Importantly, proteasome inhibition (PI) leads to different responses in both cell types. Tumor cells showed a dose-dependent glycogen synthase kinase-3 (GSK-3)β inhibition, a huge increase in the expression of the transcription factor CHOP and an active processing of caspase-8. By contrast, MCF10A cells fully activated GSK-3β and showed a lower expression of both CHOP and processed caspase-8. These molecular differences were reflected in a dose-dependent autophagy activation and cell death in tumor cells, while non-tumor cells exhibited the formation of inclusion bodies and a decrease in the cell death rate. Importantly, the behavior of the MCF7 cells can be reproduced in MCF10A cells when GSK-3β and the proteasome were simultaneously inhibited. Under this situation, MCF10A cells strongly activated autophagy, showing minimal inclusion bodies, increased CHOP expression and cell death rate. These findings support GSK-3β signaling as a key mechanism in regulating autophagy activation or inclusion formation in human tumor or non-tumor breast cells, respectively, which may shed new light on breast cancer control. PMID:23559006

  10. Establishment and characterization of five new human renal tumor xenografts.

    PubMed Central

    Beniers, A. J.; Peelen, W. P.; Schaafsma, H. E.; Beck, J. L.; Ramaekers, F. C.; Debruyne, F. M.; Schalken, J. A.

    1992-01-01

    Ten different human renal cell carcinoma (RCC) primary tumors were xenografted into BALB/c nu/nu mice. Five of the tumors (NU-10, NU-12, NU-20, NU-22, and NU-28) gave rise to serially transplantable tumors that were further characterized. Histology, DNA index, immunohistochemical characteristics, growth rate, and clonogenic potential were followed from primary tumor to the 5th to 15th transplant passage. Only one of the tumors (NU-20) showed remarkable instability for all tested parameters in the first five transplant passages. Histology of the other tumors was essentially the same to the histology of the primary tumors, although differences between human and host-derived vessels were apparent. DNA index values in general showed a trend toward an aneuploid character of the xenografts. Immunohistochemical analyses showed a loss of intensity of staining but a concomitant rise in the fraction of positively staining cells with antibodies against cytokeratins, vimentin, tumor-associated antigens, and human leukocyte antigen (HLA) class I antigens. Human leukocyte antigen class II antigen expression showed a loss of intensity as well as a decrease in the fraction of positive cells. Tumor doubling time was lowest in transplant passage number 0, and stable growth was noticed in transplant passages 1 through 4. Clonogenic potential of four of the lines was higher for the xenografts than for the primary tumors. The authors conclude that, on xenografting, histologic characteristics of the primary tumor are essentially conserved. Progression in the first transplant passages, however, results in tumors with a more aggressive character. Images Figure 1 PMID:1739137

  11. RALBP1/RLIP76 depletion in mice suppresses tumor growth by inhibiting tumor neovascularization

    PubMed Central

    Lee, Seunghyung; Wurtzel, Jeremy G.T.; Singhal, Sharad S.; Awasthi, Sanjay; Goldfinger, Lawrence E.

    2012-01-01

    RalBP1/RLIP76 is a widely expressed multifunctional protein that binds the Ral and R-Ras small GTPases. In the mouse, RLIP76 is non-essential but its depletion or blockade promotes tumorigenesis and heightens the sensitivity of normal and tumor cells to radiation and cytotoxic drugs. However, its pathobiological functions which support tumorigenesis are not well understood. Here we show that RLIP76 is required for angiogenesis and for efficient neovascularization of primary solid tumors. Tumor growth from implanted melanoma or carcinoma cells was blunted in RLIP76−/− mice. An X-ray microCT-based method to model tumor vascular structures revealed defects in both the extent and form of tumor angiogenesis in RLIP76−/− mice. Specifically, tumor vascular volumes were diminished and vessels were fewer in number, shorter, and narrower in RLIP76−/− mice than in wild-type mice. Moreover, we found that angiogenesis was blunted in mutant mice in the absence of tumor cells, with endothelial cells isolated from these animals exhibiting defects in migration, proliferation and cord formation in vitro. Taken together, our results establish that RLIP76 is required for efficient endothelial cell function and angiogenesis in solid tumors. PMID:22902412

  12. Detection of Human Polyomavirus 7 in human thymic epithelial tumors

    PubMed Central

    Rennspiess, Dorit; Pujari, Sreedhar; Keijzers, Marlies; Abdul-Hamid, Myrurgia A.; Hochstenbag, Monique; Dingemans, Anne-Marie; Kurz, Anna Kordelia; Speel, Ernst-Jan; Haugg, Anke; Pastrana, Diana V.; Buck, Christopher B.; De Baets, Marc H.; zur Hausen, Axel

    2014-01-01

    Introduction Although the molecular genetics possibly underlying the pathogenesis of human thymoma have been extensively studied, its etiology remains poorly understood. Since murine polyomavirus consistently induces thymomas in mice, we assessed the presence of the novel human polyomavirus 7 (HPyV7) in human thymic epithelial tumors. Methods HPyV7-DNA Fluorescence in situ hybridization (FISH), DNA-PCR and immuno-histochemistry (IHC) were performed in 37 thymomas. Of these, 26 were previously diagnosed with myasthenia gravis (MG). In addition, 20 thymic hyperplasias and 20 fetal thymic tissues were tested. Results HPyV7-FISH revealed specific nuclear hybridization signals within the neoplastic epithelial cells of 23 thymomas (62.2%). With some exceptions, the HPyV7-FISH data correlated with the HPyV7-DNA PCR. By IHC large T antigen (LTAg) expression of HPyV7 was detected, and double staining confirmed its expression in the neoplastic epithelial cells. Eighteen of the 26 MG-positive and 7 of the 11 MG-negative thymomas were HPyV7-positive. 40% of the 20 hyperplastic thymi were HPyV7-positive by PCR as confirmed by FISH and IHC in the follicular lymphocytes. All 20 fetal thymi tested HPyV7-negative. Conclusions The presence of HPyV7-DNA and LTAg expression in the majority of thymomas possibly link HPyV7 to human thymomagenesis. Further investigations are needed to elucidate the possible associations of HPyV7 and MG. PMID:25526237

  13. N-(3-oxo-acyl) homoserine lactone inhibits tumor growth independent of Bcl-2 proteins

    PubMed Central

    Zhao, Guoping; Neely, Aaron M.; Schwarzer, Christian; Lu, Huayi; Whitt, Aaron G.; Stivers, Nicole S.; Burlison, Joseph A.; White, Carl; Machen, Terry E.; Li, Chi

    2016-01-01

    Pseudomonas aeruginosa produces N-(3-oxododecanoyl)-homoserine lactone (C12) as a quorum-sensing molecule for bacterial communication. C12 has also been reported to induce apoptosis in various types of tumor cells. However, the detailed molecular mechanism of C12-triggerred tumor cell apoptosis is still unclear. In addition, it is completely unknown whether C12 possesses any potential therapeutic effects in vivo. Our data indicate that, unlike most apoptotic inducers, C12 evokes a novel form of apoptosis in tumor cells through inducing mitochondrial membrane permeabilization independent of both pro- and anti-apoptotic Bcl-2 proteins. Importantly, C12 inhibits tumor growth in animals regardless of either pro- or anti-apoptotic Bcl-2 proteins. Furthermore, opposite to conventional chemotherapeutics, C12 requires paraoxonase 2 (PON2) to exert its cytotoxicity on tumor cells in vitro and its inhibitory effects on tumor growth in vivo. Overall, our results demonstrate that C12 inhibits tumor growth independent of both pro- and anti-apoptotic Bcl-2 proteins, and through inducing unique apoptotic signaling mediated by PON2 in tumor cells. PMID:26758417

  14. N-(3-oxo-acyl) homoserine lactone inhibits tumor growth independent of Bcl-2 proteins.

    PubMed

    Zhao, Guoping; Neely, Aaron M; Schwarzer, Christian; Lu, Huayi; Whitt, Aaron G; Stivers, Nicole S; Burlison, Joseph A; White, Carl; Machen, Terry E; Li, Chi

    2016-02-01

    Pseudomonas aeruginosa produces N-(3-oxododecanoyl)-homoserine lactone (C12) as a quorum-sensing molecule for bacterial communication. C12 has also been reported to induce apoptosis in various types of tumor cells. However, the detailed molecular mechanism of C12-triggerred tumor cell apoptosis is still unclear. In addition, it is completely unknown whether C12 possesses any potential therapeutic effects in vivo. Our data indicate that, unlike most apoptotic inducers, C12 evokes a novel form of apoptosis in tumor cells through inducing mitochondrial membrane permeabilization independent of both pro- and anti-apoptotic Bcl-2 proteins. Importantly, C12 inhibits tumor growth in animals regardless of either pro- or anti-apoptotic Bcl-2 proteins. Furthermore, opposite to conventional chemotherapeutics, C12 requires paraoxonase 2 (PON2) to exert its cytotoxicity on tumor cells in vitro and its inhibitory effects on tumor growth in vivo. Overall, our results demonstrate that C12 inhibits tumor growth independent of both pro- and anti-apoptotic Bcl-2 proteins, and through inducing unique apoptotic signaling mediated by PON2 in tumor cells. PMID:26758417

  15. Vasoactive Intestinal Peptide Inhibits Human Small-Cell Lung Cancer Proliferation in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Maruno, Kaname; Absood, Afaf; Said, Sami I.

    1998-11-01

    Small-cell lung carcinoma (SCLC) is an aggressive, rapidly growing and metastasizing, and highly fatal neoplasm. We report that vasoactive intestinal peptide inhibits the proliferation of SCLC cells in culture and dramatically suppresses the growth of SCLC tumor-cell implants in athymic nude mice. In both cases, the inhibition was mediated apparently by a cAMP-dependent mechanism, because the inhibition was enhanced by the adenylate cyclase activator forskolin and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine in proportion to increases in intracellular cAMP levels, and the inhibition was abolished by selective inhibition of cAMP-dependent protein kinase. If confirmed in clinical trials, this antiproliferative action of vasoactive intestinal peptide may offer a new and promising means of suppressing SCLC in human subjects, without the toxic side effects of chemotherapeutic agents.

  16. Pyrrolidine dithiocarbamate-zinc(II) and -copper(II) complexes induce apoptosis in tumor cells by inhibiting the proteasomal activity

    SciTech Connect

    Milacic, Vesna; Chen Di; Giovagnini, Lorena; Diez, Alejandro; Fregona, Dolores; Dou, Q. Ping

    2008-08-15

    Zinc and copper are trace elements essential for proper folding, stabilization and catalytic activity of many metalloenzymes in living organisms. However, disturbed zinc and copper homeostasis is reported in many types of cancer. We have previously demonstrated that copper complexes induced proteasome inhibition and apoptosis in cultured human cancer cells. In the current study we hypothesized that zinc complexes could also inhibit the proteasomal chymotrypsin-like activity responsible for subsequent apoptosis induction. We first showed that zinc(II) chloride was able to inhibit the chymotrypsin-like activity of a purified 20S proteasome with an IC{sub 50} value of 13.8 {mu}M, which was less potent than copper(II) chloride (IC{sub 50} 5.3 {mu}M). We then compared the potencies of a pyrrolidine dithiocarbamate (PyDT)-zinc(II) complex and a PyDT-copper(II) complex to inhibit cellular proteasomal activity, suppress proliferation and induce apoptosis in various human breast and prostate cancer cell lines. Consistently, zinc complex was less potent than copper complex in inhibiting the proteasome and inducing apoptosis. Additionally, zinc and copper complexes appear to use somewhat different mechanisms to kill tumor cells. Zinc complexes were able to activate calpain-, but not caspase-3-dependent pathway, while copper complexes were able to induce activation of both proteases. Furthermore, the potencies of these PyDT-metal complexes depend on the nature of metals and also on the ratio of PyDT to the metal ion within the complex, which probably affects their stability and availability for interacting with and inhibiting the proteasome in tumor cells.

  17. Pyrrolidine dithiocarbamate-zinc(II) and -copper(II) complexes induce apoptosis in tumor cells by inhibiting the proteasomal activity☆

    PubMed Central

    Milacic, Vesna; Chen, Di; Giovagnini, Lorena; Diez, Alejandro; Fregona, Dolores; Dou, Q. Ping

    2013-01-01

    Zinc and copper are trace elements essential for proper folding, stabilization and catalytic activity of many metalloenzymes in living organisms. However, disturbed zinc and copper homeostasis is reported in many types of cancer. We have previously demonstrated that copper complexes induced proteasome inhibition and apoptosis in cultured human cancer cells. In the current study we hypothesized that zinc complexes could also inhibit the proteasomal chymotrypsin-like activity responsible for subsequent apoptosis induction. We first showed that zinc(II) chloride was able to inhibit the chymotrypsin-like activity of a purified 20S proteasome with an IC50 value of 13.8 μM, which was less potent than copper(II) chloride (IC50 5.3 μM). We then compared the potencies of a pyrrolidine dithiocarbamate (PyDT)-zinc(II) complex and a PyDT-copper(II) complex to inhibit cellular proteasomal activity, suppress proliferation and induce apoptosis in various human breast and prostate cancer cell lines. Consistently, zinc complex was less potent than copper complex in inhibiting the proteasome and inducing apoptosis. Additionally, zinc and copper complexes appear to use somewhat different mechanisms to kill tumor cells. Zinc complexes were able to activate calpain-, but not caspase-3-dependent pathway, while copper complexes were able to induce activation of both proteases. Furthermore, the potencies of these PyDT-metal complexes depend on the nature of metals and also on the ratio of PyDT to the metal ion within the complex, which probably affects their stability and availability for interacting with and inhibiting the proteasome in tumor cells. PMID:18501397

  18. ATR inhibition preferentially targets homologous recombination-deficient tumor cells.

    PubMed

    Krajewska, M; Fehrmann, R S N; Schoonen, P M; Labib, S; de Vries, E G E; Franke, L; van Vugt, M A T M

    2015-06-01

    Homologous recombination (HR) is required for faithful repair of double-strand DNA breaks. Defects in HR repair cause severe genomic instability and challenge cellular viability. Paradoxically, various cancers are HR defective and have apparently acquired characteristics to survive genomic instability. We aimed to identify these characteristics to uncover therapeutic targets for HR-deficient cancers. Cytogenetic analysis of 1143 ovarian cancers showed that the degree of genomic instability was correlated to amplification of replication checkpoint genes ataxia telangiectasia and Rad3-related kinase (ATR) and CHEK1. To test whether genomic instability leads to increased reliance on replication checkpoint signaling, we inactivated Rad51 to model HR-related genomic instability. Rad51 inactivation caused defective HR repair and induced aberrant replication dynamics. Notably, inhibition of Rad51 led to increased ATR/checkpoint kinase-1 (Chk1)-mediated replication stress signaling. Importantly, inhibition of ATR or Chk1 preferentially killed HR-deficient cancer cells. Combined, our data show that defective HR caused by Rad51 inhibition results in differential sensitivity for ATR and Chk1 inhibitors, implicating replication checkpoint kinases as potential drug targets for HR-defective cancers. PMID:25174396

  19. Inhibition and regression of tumors in hamster DMBA model following laser microvascular targeting

    NASA Astrophysics Data System (ADS)

    McMillan, Kathleen; Wang, Zhi; Shapshay, Stanley M.

    1998-07-01

    Vascular targeting is a recent approach to cancer therapy that aims at damaging tumor vasculature to induce tumor cell hypoxia and subsequent cell death. Squamous cell cancer arises in the superficial mucosal and cutaneous epithelial layers, and tumor microvasculature therefore may be particularly well suited for targeting by selective photothermolysis. An initial evaluation of the effect of selective eradication of microvasculature on tumor development was undertaken here using the chemically-induced hamster cheek pouch model and a 585 nm pulsed dye laser. In a first group of 6 hamsters, progression of premalignant mucosal lesions was compared between control and laser treatment groups, and laser-induced regression of established tumors was evaluated. In a second group of 12 hamsters, the number of laser treatments required to produce complete regression of tumors of the buccal mucosa was determined. The effect of the laser on tumors appearing on the skin in these animals was also investigated. These experiments showed that laser treatment inhibited tumor development and caused complete regression of established tumors 10 mm3 or smaller. Photothermal microvascular targeting may be useful in treating dyplasia and early tumors of the upper aerodigestive tract and skin, with fewer adverse sequelae than existing modalities.

  20. Squalamine treatment of human tumors in nu/nu mice enhances platinum-based chemotherapies.

    PubMed

    Williams, J I; Weitman, S; Gonzalez, C M; Jundt, C H; Marty, J; Stringer, S D; Holroyd, K J; Mclane, M P; Chen, Q; Zasloff, M; Von Hoff, D D

    2001-03-01

    Squalamine, an antiangiogenic aminosterol, is presently undergoing Phase II clinical trials in cancer patients. To broaden our understanding of the clinical potential for squalamine, this agent was evaluated in nu/nu mouse xenograft models using the chemoresistant MV-522 human non-small cell lung carcinoma and the SD human neuroblastoma lines. Squalamine was studied alone and in combination with either cisplatin or paclitaxel plus carboplatin. Squalamine alone produced a modest MV-522 tumor growth inhibition (TGI) and yielded a TGI with cisplatin that was better than cisplatin alone. Squalamine also significantly enhanced the activity of paclitaxel/carboplatin combination therapy in the MV-522 tumor model. Squalamine similarly improved the effectiveness of cisplatin in producing TGI when screened against the SD human neuroblastoma xenograft. Xenograft tumor shrinkage was seen for the MV-522 tumor in combination treatments including squalamine, whereas no tumor shrinkage was seen when squalamine was omitted from the treatment regimen. To gain a greater understanding of the mechanism by which squalamine inhibited tumor growth in the xenograft studies, in vitro experiments were carried out with vascular endothelial growth factor-stimulated human umbilical vein endothelial cells in culture exposed to squalamine. Squalamine treatment was found to retard two cellular events necessary for angiogenesis, inducing disorganization of F-actin stress fibers and causing a concomitant reduction of detectable cell the surface molecular endothelial cadherin (VE-cadherin). We propose that the augmentation by squalamine of cytotoxicity from platinum-based therapies is attributable to interference by squalamine with the ability of stimuli to promote endothelial cell movement and cell-cell communication necessary for growth of new blood vessels in xenografts after chemotherapeutic injury to the tumor. PMID:11297269

  1. ACE2 overexpression inhibits acquired platinum resistance-induced tumor angiogenesis in NSCLC.

    PubMed

    Cheng, Qijian; Zhou, Ling; Zhou, Jianping; Wan, Huanying; Li, Qingyun; Feng, Yun

    2016-09-01

    Angiotensin II (AngII) is a multifunctional bioactive peptide in the renin-angiotensin system (RAS). Angiotensin-converting enzyme 2 (ACE2) is a newly identified component of RAS. We previously reported that ACE2 overexpression may inhibit cell growth and vascular endothelial growth factor (VEGF) production in vitro and in vivo. In the present study, we investigated the effect of ACE2 on tumor-associated angiogen-esis after the development of acquired platinum resistance in non-small cell lung cancer (NSCLC). Four NSCLC cell lines, A549, LLC, A549-DDP and LLC-DDP, were used in vitro, while A549 and A549-DDP cells were used in vivo. A549-DDP and LLC-DDP cells were newly established at our institution as acquired platinum-resistant sublines by culturing the former parent cells in cisplatin (CDDP)-containing conditioned medium for 6 months. These platinum-resistant cells showed significantly higher angiotensin II type 1 receptor (AT1R), ACE and VEGF production and lower ACE2 expression than their corresponding parent cells. We showed that ACE2 overexpression inhibited the production of VEGF in vitro and in vivo compared to their corresponding parent cells. We also found that ACE2 overexpression reduced the expression of AT1R and ACE. Additionally, we confirmed that ACE2 overexpres-sion inhibited cell growth and VEGF production while simultaneously suppressing ACE and AT1R expression in human lung cancer xenografts. Our findings indicate that ACE2 overexpression may potentially suppress angiogenesis in NSCLC after the development of acquired platinum resistance. PMID:27460845

  2. Pain inhibits pain; human brainstem mechanisms.

    PubMed

    Youssef, A M; Macefield, V G; Henderson, L A

    2016-01-01

    Conditioned pain modulation is a powerful analgesic mechanism, occurring when a painful stimulus is inhibited by a second painful stimulus delivered at a different body location. Reduced conditioned pain modulation capacity is associated with the development of some chronic pain conditions and the effectiveness of some analgesic medications. Human lesion studies show that the circuitry responsible for conditioned pain modulation lies within the caudal brainstem, although the precise nuclei in humans remain unknown. We employed brain imaging to determine brainstem sites responsible for conditioned pain modulation in 54 healthy individuals. In all subjects, 8 noxious heat stimuli (test stimuli) were applied to the right side of the mouth and brain activity measured using functional magnetic resonance imaging. This paradigm was then repeated. However, following the fourth noxious stimulus, a separate noxious stimulus, consisting of an intramuscular injection of hypertonic saline into the leg, was delivered (conditioning stimulus). During this test and conditioning stimulus period, 23 subjects displayed conditioned pain modulation analgesia whereas 31 subjects did not. An individual's analgesic ability was not influenced by gender, pain intensity levels of the test or conditioning stimuli or by psychological variables such as pain catastrophizing or fear of pain. Brain images were processed using SPM8 and the brainstem isolated using the SUIT toolbox. Significant increases in signal intensity were determined during each test stimulus and compared between subjects that did and did not display CPM analgesia (p<0.05, small volume correction). The expression of analgesia was associated with reduction in signal intensity increases during each test stimulus in the presence of the conditioning stimulus in three brainstem regions: the caudalis subdivision of the spinal trigeminal nucleus, i.e., the primary synapse, the region of the subnucleus reticularis dorsalis and in the

  3. Yap1 promotes the survival and self-renewal of breast tumor initiating cells via inhibiting Smad3 signaling

    PubMed Central

    Sun, Jian-Guo; Chen, Xie-Wan; Zhang, Lu-Ping; Wang, Jiang; Diehn, Max

    2016-01-01

    Tumor initiating cells (TICs) serve as the root of tumor growth. After identifying TICs in spontaneous breast tumors of the MMTV-Wnt1 mouse model, we confirmed the specific expression and activation of Yes-associated protein 1 (Yap1) within TICs. To investigate the role of Yap1 in the self-renewal of breast TICs and the underlying mechanism, we sorted CD49fhighEpCAMlow cells as breast TICs. Active Yap1 with ectopic expression in breast TICs promoted their colony formation in vitro (p< 0.01) and self-renewal in vivo (p< 0.01), and led to a 4-fold increase in TIC frequency (p< 0.05). A conditional knock-out mouse was reconstructed to generate Yap1 knock-out breast tumors. The loss of Yap1 led to a dramatic growth disadvantage of breast TICs in vitro (p< 0.01) and in vivo (p< 0.01), and it also led to an over 200-fold decrease in TIC frequency (p< 0.01). The expression of active Yap1 was negatively correlated with that of phosphorylated Smad3 (p-Smad3). Transforming growth factor β (TGF-β) served as a strong enhancer of Smad3 and an inhibitor of clonogenesis of TICs. The presence of SIS3, a specific inhibitor of Smad3, could rescue the TGF-β -induced growth inhibition and reverse the Smad3 inhibition by Yap1. Analysis of a database containing 2,072 human breast cancer samples showed that higher expressions of Yap1 correlated with a poorer outcome of a 15-year survival rate and median overall survival (mOS)in patients, especially in those with basal breast tumors without estrogen receptor 1 (ER) expression. The findings indicate that active Yap1 promotes the self-renewal of breast TICs by inhibiting Smad3 signaling. PMID:26695440

  4. Yap1 promotes the survival and self-renewal of breast tumor initiating cells via inhibiting Smad3 signaling.

    PubMed

    Sun, Jian-Guo; Chen, Xie-Wan; Zhang, Lu-Ping; Wang, Jiang; Diehn, Max

    2016-03-01

    Tumor initiating cells (TICs) serve as the root of tumor growth. After identifying TICs in spontaneous breast tumors of the MMTV-Wnt1 mouse model, we confirmed the specific expression and activation of Yes-associated protein 1 (Yap1) within TICs. To investigate the role of Yap1 in the self-renewal of breast TICs and the underlying mechanism, we sorted CD49fhighEpCAMlow cells as breast TICs. Active Yap1 with ectopic expression in breast TICs promoted their colony formation in vitro (p< 0.01) and self-renewal in vivo (p< 0.01), and led to a 4-fold increase in TIC frequency (p< 0.05).A conditional knock-out mouse was reconstructed to generate Yap1 knock-out breast tumors. The loss of Yap1 led to a dramatic growth disadvantage of breast TICs in vitro (p< 0.01) and in vivo (p< 0.01), and it also led to an over 200-fold decrease in TIC frequency (p< 0.01). The expression of active Yap1 was negatively correlated with that of phosphorylated Smad3 (p-Smad3).Transforming growth factor β (TGF-β) served as a strong enhancer of Smad3 and an inhibitor of clonogenesis of TICs. The presence of SIS3, a specific inhibitor of Smad3, could rescue the TGF-β -induced growth inhibition and reverse the Smad3 inhibition by Yap1. Analysis of a database containing 2,072 human breast cancer samples showed that higher expressions of Yap1 correlated with a poorer outcome of a 15-year survival rate and median overall survival (mOS)in patients, especially in those with basal breast tumors without estrogen receptor 1 (ER) expression. The findings indicate that active Yap1 promotes the self-renewal of breast TICs by inhibiting Smad3 signaling. PMID:26695440

  5. Ranitidine modifies myeloid cell populations and inhibits breast tumor development and spread in mice.

    PubMed

    Vila-Leahey, Ava; Oldford, Sharon A; Marignani, Paola A; Wang, Jun; Haidl, Ian D; Marshall, Jean S

    2016-07-01

    Histamine receptor 2 (H2) antagonists are widely used clinically for the control of gastrointestinal symptoms, but also impact immune function. They have been reported to reduce tumor growth in established colon and lung cancer models. Histamine has also been reported to modify populations of myeloid-derived suppressor cells (MDSCs). We have examined the impact of the widely used H2 antagonist ranitidine, on both myeloid cell populations and tumor development and spread, in three distinct models of breast cancer that highlight different stages of cancer progression. Oral ranitidine treatment significantly decreased the monocytic MDSC population in the spleen and bone marrow both alone and in the context of an orthotopic breast tumor model. H2 antagonists ranitidine and famotidine, but not H1 or H4 antagonists, significantly inhibited lung metastasis in the 4T1 model. In the E0771 model, ranitidine decreased primary tumor growth while omeprazole treatment had no impact on tumor development. Gemcitabine treatment prevented the tumor growth inhibition associated with ranitidine treatment. In keeping with ranitidine-induced changes in myeloid cell populations in non-tumor-bearing mice, ranitidine also delayed the onset of spontaneous tumor development, and decreased the number of tumors that developed in LKB1(-/-)/NIC mice. These results indicate that ranitidine alters monocyte populations associated with MDSC activity, and subsequently impacts breast tumor development and outcome. Ranitidine has potential as an adjuvant therapy or preventative agent in breast cancer and provides a novel and safe approach to the long-term reduction of tumor-associated immune suppression. PMID:27622015

  6. Ranitidine modifies myeloid cell populations and inhibits breast tumor development and spread in mice

    PubMed Central

    Vila-Leahey, Ava; Oldford, Sharon A.; Marignani, Paola A.; Wang, Jun; Haidl, Ian D.; Marshall, Jean S.

    2016-01-01

    ABSTRACT Histamine receptor 2 (H2) antagonists are widely used clinically for the control of gastrointestinal symptoms, but also impact immune function. They have been reported to reduce tumor growth in established colon and lung cancer models. Histamine has also been reported to modify populations of myeloid-derived suppressor cells (MDSCs). We have examined the impact of the widely used H2 antagonist ranitidine, on both myeloid cell populations and tumor development and spread, in three distinct models of breast cancer that highlight different stages of cancer progression. Oral ranitidine treatment significantly decreased the monocytic MDSC population in the spleen and bone marrow both alone and in the context of an orthotopic breast tumor model. H2 antagonists ranitidine and famotidine, but not H1 or H4 antagonists, significantly inhibited lung metastasis in the 4T1 model. In the E0771 model, ranitidine decreased primary tumor growth while omeprazole treatment had no impact on tumor development. Gemcitabine treatment prevented the tumor growth inhibition associated with ranitidine treatment. In keeping with ranitidine-induced changes in myeloid cell populations in non-tumor-bearing mice, ranitidine also delayed the onset of spontaneous tumor development, and decreased the number of tumors that developed in LKB1−/−/NIC mice. These results indicate that ranitidine alters monocyte populations associated with MDSC activity, and subsequently impacts breast tumor development and outcome. Ranitidine has potential as an adjuvant therapy or preventative agent in breast cancer and provides a novel and safe approach to the long-term reduction of tumor-associated immune suppression. PMID:27622015

  7. Prolyl hydroxylase-2 inhibits liver tumor cell proliferation and cyclin D1 expression in a hydroxylase-dependent manner.

    PubMed

    Tao, Yifeng; Lin, Feng; Li, Ruidong; Shen, Jie; Wang, Zhengxin

    2016-08-01

    Prolyl hydroxylase 2 is a key regulator of hypoxia-inducible factor 1 alpha protein, and has previously been implicated as a tumor suppressor in various cancers. However, the function of prolyl hydroxylase 2 in liver cancer has yet to be elucidated. Characterization of prolyl hydroxylase 2 function and related mechanisms in liver cancer may enable the development of targeted therapy. Here we found that prolyl hydroxylase 2 overexpression in human hepatocellular carcinoma cancer cell lines inhibited cell proliferation, while prolyl hydroxylase 2 knockdown enhanced cell proliferation. Further analyses revealed that the prolyl hydroxylase 2-mediated inhibition of cell proliferation was due to a cell cycle arrest at the G1/S transition. Moreover, the block in cell cycle was facilitated by negative regulation of cyclin D1, a process dependent on the hydroxylase activity of prolyl hydroxylase 2. Using an in vivo xenograft mouse model, we found that the overexpression of prolyl hydroxylase 2 led to a reduction in tumor size. Evaluation of paired human liver cancer patient samples revealed that prolyl hydroxylase 2 protein levels were significantly reduced in 6 of the 10 cancer tissues as compared to their respective normal tissue controls. Furthermore, elevated expression of prolyl hydroxylase 2 was associated with significantly prolonged survival in patients with liver cancer. These results suggest that prolyl hydroxylase 2 plays an important tumor suppressive role in liver cancer and may prove to be of prognostic and therapeutic value. PMID:27307407

  8. Binding of the Fap2 protein of Fusobacterium nucleatum to human inhibitory receptor TIGIT protects tumors from immune cell attack.

    PubMed

    Gur, Chamutal; Ibrahim, Yara; Isaacson, Batya; Yamin, Rachel; Abed, Jawad; Gamliel, Moriya; Enk, Jonatan; Bar-On, Yotam; Stanietsky-Kaynan, Noah; Coppenhagen-Glazer, Shunit; Shussman, Noam; Almogy, Gideon; Cuapio, Angelica; Hofer, Erhard; Mevorach, Dror; Tabib, Adi; Ortenberg, Rona; Markel, Gal; Miklić, Karmela; Jonjic, Stipan; Brennan, Caitlin A; Garrett, Wendy S; Bachrach, Gilad; Mandelboim, Ofer

    2015-02-17

    Bacteria, such as Fusobacterium nucleatum, are present in the tumor microenvironment. However, the immunological consequences of intra-tumoral bacteria remain unclear. Here, we have shown that natural killer (NK) cell killing of various tumors is inhibited in the presence of various F. nucleatum strains. Our data support that this F. nucleatum-mediated inhibition is mediated by human, but not by mouse TIGIT, an inhibitory receptor present on all human NK cells and on various T cells. Using a library of F. nucleatum mutants, we found that the Fap2 protein of F. nucleatum directly interacted with TIGIT, leading to the inhibition of NK cell cytotoxicity. We have further demonstrated that tumor-infiltrating lymphocytes expressed TIGIT and that T cell activities were also inhibited by F. nucleatum via Fap2. Our results identify a bacterium-dependent, tumor-immune evasion mechanism in which tumors exploit the Fap2 protein of F. nucleatum to inhibit immune cell activity via TIGIT. PMID:25680274

  9. Deuterium-depleted water inhibits human lung carcinoma cell growth by apoptosis

    PubMed Central

    CONG, FENG-SONG; ZHANG, YA-RU; SHENG, HONG-CAI; AO, ZONG-HUA; ZHANG, SU-YI; WANG, JU-YONG

    2010-01-01

    To investigate the in vivo and in vitro inhibitory effects of deuterium-depleted water (DDW) on human lung cancer and the possible mechanisms underlying these effects, we cultured and treated human lung carcinoma cell line A549 and human embryonic lung fibroblasts HLF-1 with various concentrations of DDW from 2 to 72 h. Cellular growth inhibition rates were determined using the 3-(4, 5-dimethyldiazol-2-yl)-2, 5-diphenyltetrazolium-bromide) (MTT) proliferation assay. A549 cells were treated with 50±5 ppm DDW, and the morphology and structure of cells were observed by scanning electron microscopy (SEM). We observed alterations in the cellular skeleton by transmission electron microscopy (TEM) and changes in cell cycle by flow cytometry. Our data showed that DDW significantly inhibited the proliferation of A549 cells at a specific time point, and cells demonstrated the characteristic morphological changes of apoptosis under SEM and TEM. The length of the S phase increased significantly in cells treated with 50 ppm DDW, whereas the G0 to G1 phase and G2 to M phase were decreased. We observed DDW-induced cellular apoptosis using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and DNA fragment analyses. In addition, we established a tumor transplantion model by injecting H460 tumor cells into subcutaneous tissue of BALB/c mice treated with DDW for 60 days. We determined the tumor inhibition rate of treated and control groups and found that the tumor weight was significantly decreased and the tumor inhibition rate was approximately 30% in the DDW group. We conclude that DDW is a promising new anticancer agent with potential for future clinical application. PMID:22993540

  10. Simultaneous Inhibition of EGFR, VEGFR and PDGFR Signaling Combined with Gemcitabine Produces Therapy of Human Pancreatic Carcinoma and Prolongs Survival in an Orthotopic Nude Mouse Model

    PubMed Central

    Yokoi, Kenji; Sasaki, Takamitsu; Bucana, Corazon D.; Fan, Dominic; Baker, Cheryl H.; Kitadai, Yasuhiko; Kuwai, Toshio; Abbruzzese, James L.; Fidler, Isaiah J.

    2006-01-01

    Although gemcitabine has been approved as the first-line chemotherapeutic reagent for pancreatic cancer, its response rate is low and average survival duration is still only marginal. Because epidermal growth factor receptor (EGFR), vascular endothelial growth factor receptor (VEGFR), and platelet-derived growth factor receptor (PDGFR) modulate tumor progression, we hypothesized that inhibition of phosphorylation of all three on tumor cells, tumor-associated endothelial cells, and stroma cells would improve the treatment efficacy of gemcitabine in an orthotopic pancreatic tumor model in nude mice and prolong survival. We implanted L3.6pl, a human pancreatic cancer cell, in the pancreas of nude mice. We found that tumor-associated endothelial cells in this model highly expressed phosphorylated EGFR, VEGFR, and PDGFR. Oral administration of AEE788, a dual tyrosine kinase inhibitor against EGFR and VEGFR, decreased phosphorylation of EGFR and VEGFR. PDGFR phosphorylation was inhibited by STI571. Although intraperitoneal (i.p.) injection of gemcitabine did not inhibit tumor growth, its combination with AEE788 and STI571 produced >80% inhibition of tumor growth and prolonged survival in parallel with increases in number of tumor cells and tumor-associated endothelial cell apoptosis, decreased microvascular density, decreased proliferation rate, and prolonged survival. STI571 treatment also decreased pericyte coverage on tumor-associated endothelial cells. Thus, inhibiting phosphorylation of EGFR, VEGFR, and PDGFR in combination with gemcitabine enhanced the efficacy of gemcitabine, resulting in inhibition of experimental human pancreatic cancer growth and significant prolongation of survival. PMID:16288027

  11. Inhibition by alcohols of the localization of radioactive nitrosonornicotine in sites of tumor formation

    SciTech Connect

    Waddell, W.J.; Marlowe, C.

    1983-06-01

    Oral administration of ethanol, n-butanol, or t-butanol to mice 20 minutes before injection of carbon-14-labeled nitrosonornicotine inhibited the localization of radioactivity in bronchial and salivary duct epithelium and in the liver. Localization of radioactivity in the nasal epithelium and esophagus was not significantly reduced. These alcohols therefore may selectively inhibit tumor formation in three of the five sites where this carcinogen typically acts.

  12. Aminomethylphosphonic acid inhibits growth and metastasis of human prostate cancer in an orthotopic xenograft mouse model.

    PubMed

    Parajuli, Keshab Raj; Zhang, Qiuyang; Liu, Sen; You, Zongbing

    2016-03-01

    Aminomethylphosphonic acid (AMPA) has been shown to inhibit prostate cancer cell growth in vitro. The purpose of the present study was to determine if AMPA could inhibit growth and metastasis of prostate cancer in vivo. Human prostate cancer PC-3-LacZ-luciferase cells were implanted into the ventral lateral lobes of the prostate in 39 athymic Nu/Nu nude male mice. Seven days later, mice were randomized into the control group (n = 14, treated intraperitoneally with phosphate buffered saline), low dose group (n = 10, treated intraperitoneally with AMPA at 400 mg/kg body weight/day), and high dose group (n = 15, treated intraperitoneally with AMPA at 800 mg/kg body weight/day). Tumor growth and metastasis were examined every 4-7 days by bioluminescence imaging of live mice. We found that AMPA treatment significantly inhibited growth and metastasis of orthotopic xenograft prostate tumors and prolonged the survival time of the mice. AMPA treatment decreased expression of BIRC2 and activated caspase 3, leading to increased apoptosis in the prostate tumors. AMPA treatment decreased expression of cyclin D1. AMPA treatment also reduced angiogenesis in the prostate tumors. Taken together, these results demonstrate that AMPA can inhibit prostate cancer growth and metastasis, suggesting that AMPA may be developed into a therapeutic agent for the treatment of prostate cancer. PMID:26840261

  13. Aminomethylphosphonic acid inhibits growth and metastasis of human prostate cancer in an orthotopic xenograft mouse model

    PubMed Central

    Parajuli, Keshab Raj; Zhang, Qiuyang; Liu, Sen; You, Zongbing

    2016-01-01

    Aminomethylphosphonic acid (AMPA) has been shown to inhibit prostate cancer cell growth in vitro. The purpose of the present study was to determine if AMPA could inhibit growth and metastasis of prostate cancer in vivo. Human prostate cancer PC-3-LacZ-luciferase cells were implanted into the ventral lateral lobes of the prostate in 39 athymic Nu/Nu nude male mice. Seven days later, mice were randomized into the control group (n = 14, treated intraperitoneally with phosphate buffered saline), low dose group (n = 10, treated intraperitoneally with AMPA at 400 mg/kg body weight/day), and high dose group (n = 15, treated intraperitoneally with AMPA at 800 mg/kg body weight/day). Tumor growth and metastasis were examined every 4-7 days by bioluminescence imaging of live mice. We found that AMPA treatment significantly inhibited growth and metastasis of orthotopic xenograft prostate tumors and prolonged the survival time of the mice. AMPA treatment decreased expression of BIRC2 and activated caspase 3, leading to increased apoptosis in the prostate tumors. AMPA treatment decreased expression of cyclin D1. AMPA treatment also reduced angiogenesis in the prostate tumors. Taken together, these results demonstrate that AMPA can inhibit prostate cancer growth and metastasis, suggesting that AMPA may be developed into a therapeutic agent for the treatment of prostate cancer. PMID:26840261

  14. Targeting Notch1 inhibits invasion and angiogenesis of human breast cancer cells via inhibition Nuclear Factor-κB signaling

    PubMed Central

    Liu, Yuan; Su, Chuanfu; Shan, Yuqing; Yang, Shouxiang; Ma, Guifeng

    2016-01-01

    Notch-1, a type-1 transmembrane protein, plays critical roles in the pathogenesis and progression of human malignancies, including breast cancer; however, the precise mechanism by which Notch-1 causes tumor cell invasion and angiogenesis remain unclear. Nuclear factor-κB (NF-κB), interleukin-8 (IL-8), vascular endothelial growth factor (VEGF), and matrix metalloproteinases (MMP) are critically involved in the processes of tumor cell invasion and metastasis, we investigated whether targeting Notch-1 could be mechanistically associated with the down-regulation of NF-κB, IL-8, VEGF, and MMP-9, resulting in the inhibition of invasion and angiogenesis of breast cancer cells. Our data showed that down-regulation of Notch-1 leads to the inactivation of NF-κB activity and inhibits the expression of its target genes, such as IL-8, VEGF and MMP-9. We also found that down-regulation of Notch-1 decreased cell invasion, and vice versa Consistent with these results, we also found that the down-regulation of Notch-1 not only decreased MMP-9 mRNA and its protein expression but also inhibited MMP-9 active form. Moreover, conditioned medium from Notch-1 siRNA-transfected breast cancer cells showed reduced levels of IL-8 and VEGF and, in turn, inhibited the tube formation of HUVECs, suggesting that down-regulation of Notch-1 leads to the inhibition of angiogenesis. Furthermore, conditioned medium from Notch-1 cDNA-transfected breast cancer cells showed increased levels of IL-8 and VEGF and, in turn, promoted the tube formation of HUVECs, suggesting that Notch-1 overexpression leads to the promotion of angiogenesis.We therefore concluded that down-regulation of Notch-1 leads to the inactivation NF-κB and its target genes (IL-8, MMP-9 and VEGF), resulting in the inhibition of invasion and angiogenesis. PMID:27398151

  15. Purification and characterization of an inhibitor (soluble tumor necrosis factor receptor) for tumor necrosis factor and lymphotoxin obtained from the serum ultrafiltrates of human cancer patients

    SciTech Connect

    Gatanaga, Tetsuya; Whang, Chenduen; Cappuccini, F.; Lucci, J.A. III; Jeffes, E.W.B. ); Kohr, W. ); Lentz, R. ); Tomich, J. ); Yamamoto, R.S. ); Granger, G.A. Memorial Cancer Inst., Long Beach, CA )

    1990-11-01

    Serum ultrafiltrates (SUF) from human patients with different types of cancer contain a blocking factor (BF) that inhibits the cytolytic activity of human tumor necrosis factor {alpha} (TNF-{alpha}) in vitro. BF is a protein with a molecular mass of 28kDa on reducing sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE). The active material was purified to homogeneity by a combination of affinity chromatography, PAGE, and high-pressure liquid chromatography. Amino acid sequence analysis revealed that BF is derived from the membrane TNF receptor. Purified BF blocks the lytic activity of recombinant human and mouse TNF-{alpha} and recombinant human lymphotoxin activity of TNF-{alpha} and recombinant human lymphotoxin on murine L929 cells in vitro. However, BF inhibits the lytic activity of TNF-{alpha} more effectively than it does that of lymphotoxin. The BF also inhibits the necrotizing activity of recombinant human TNF-{alpha} when coinjected into established cutaneous Meth A tumors in BALB/c mice. The BF may have an important role in (i) the regulation and control of TNF-{alpha} and lymphotoxin activity in cancer patients, (ii) interaction between the tumor and the host antitumor mechanisms, and (iii) use of systemically administered TNF-{alpha} in clinical trials with human cancer patients.

  16. Isolation of Mouse and Human Tumor-Associated Macrophages

    PubMed Central

    Cassetta, Luca; Noy, Roy; Swierczak, Agnieszka; Sugano, Gaël; Smith, Harriet; Wiechmann, Lisa; Pollard, Jeffrey W.

    2016-01-01

    The tumor microenvironment is a complex network of cells that support tumor progression and malignancy. It has been demonstrated that tumor cells can educate the immune system to promote a tumor-friendly environment. Among all these immune cells, tumor-associated macrophages (TAMs) are well represented and their presence in mouse models has been shown to promote tumor progression and metastasis. These effects are through the stimulation of angiogenesis, enhancement of tumor cell invasion and intravasation, immunosuppression, and at the metastatic site tumor cell extravasation and growth. However, the precise mechanisms are not fully understood. Furthermore there is limited information on TAMs derived from human cancers. For this reason it is important to be able to extract TAMs from tumors in order to compare their phenotypes, functions, and transcriptomes with normal resident tissue macrophages. Isolation of these cells is challenging due to the lack of markers and standardized protocols. Here we show an optimized protocol for the efficient isolation and extraction of resident macrophages and TAMs from human and mouse tissues by using multicolor flow cytometry. These protocols allow for the extraction of thousands of macrophages in less than 5 h from tissues as small as half a gram. The isolated macrophages can then be used for both “omics” and in vitro studies. PMID:27325269

  17. Isolation of Mouse and Human Tumor-Associated Macrophages.

    PubMed

    Cassetta, Luca; Noy, Roy; Swierczak, Agnieszka; Sugano, Gaël; Smith, Harriet; Wiechmann, Lisa; Pollard, Jeffrey W

    2016-01-01

    The tumor microenvironment is a complex network of cells that support tumor progression and malignancy. It has been demonstrated that tumor cells can educate the immune system to promote a tumor-friendly environment. Among all these immune cells, tumor-associated macrophages (TAMs) are well represented and their presence in mouse models has been shown to promote tumor progression and metastasis. These effects are through the stimulation of angiogenesis, enhancement of tumor cell invasion and intravasation, immunosuppression, and at the metastatic site tumor cell extravasation and growth. However, the precise mechanisms are not fully understood. Furthermore there is limited information on TAMs derived from human cancers. For this reason it is important to be able to extract TAMs from tumors in order to compare their phenotypes, functions, and transcriptomes with normal resident tissue macrophages. Isolation of these cells is challenging due to the lack of markers and standardized protocols. Here we show an optimized protocol for the efficient isolation and extraction of resident macrophages and TAMs from human and mouse tissues by using multicolor flow cytometry. These protocols allow for the extraction of thousands of macrophages in less than 5 h from tissues as small as half a gram. The isolated macrophages can then be used for both "omics" and in vitro studies. PMID:27325269

  18. Silibinin inhibits accumulation of myeloid-derived suppressor cells and tumor growth of murine breast cancer.

    PubMed

    Forghani, Parvin; Khorramizadeh, Mohammad R; Waller, Edmund K

    2014-04-01

    Myeloid-derived suppressor cells (MDSC)s increase in blood and accumulate in the tumor microenvironment of tumor-bearing animals, contributing to immune suppression in cancer. Silibinin, a natural flavonoid from the seeds of milk thistle, has been developed as an anti-inflammatory agent and supportive care agent to reduce the toxicity of cancer chemotherapy. The goals of this study were to evaluate the effect of silibinin on MDSCs in tumor-bearing mice and antitumor activity of silibinin in a mouse model of breast cancer. 4T1 luciferase-transfected mammary carcinoma cells were injected into in the mammary fat pad female BALB/c mice, and female CB17-Prkdc Scid/J mice. Silibinin treatment started on day 4 or day 14 after tumor inoculation continued every other day. Tumor growth was monitored by bioluminescent imaging (BLI) measuring total photon flux. Flow cytometry measured total leukocytes, CD11b(+) Gr-1(+) MDSC, and T cells in the blood and tumors of tumor-bearing mice. The effects of silibinin on 4T1 cell viability in vitro were measured by BLI. Treatment with silibinin increased overall survival in mice harboring tumors derived from the 4T1-luciferase breast cancer cell line, and reduced tumor volumes and numbers of CD11b(+) Gr-1(+) MDSCs in the blood and tumor, and increased the content of T cells in the tumor microenvironment. Silibinin failed to inhibit tumor growth in immunocompromised severe combined immunodeficiency mice, supporting the hypothesis that anticancer effect of silibinin is immune-mediated. The antitumor activity of silibinin requires an intact host immune system and is associated with decreased accumulation of blood and tumor-associated MDSCs. PMID:24574320

  19. Combination Therapy with Epigallocatechin-3-Gallate and Doxorubicin in Human Prostate Tumor Modeling Studies

    PubMed Central

    Stearns, Mark E.; Amatangelo, Michael D.; Varma, Devika; Sell, Chris; Goodyear, Shaun M.

    2010-01-01

    The polyphenol epigallocatechin-3-gallate (EGCG) in combination with doxorubicin (Dox) exhibits a synergistic activity in blocking the growth and colony-forming ability of human prostate cell lines in vitro. EGCG has been found to disrupt the mitochondrial membrane potential, induce vesiculation of mitochondria, and induce elevated poly (ADP-ribose) polymerase (PARP) cleavage and apoptosis. EGCG in combination with low levels of Dox had a synergistic effect in blocking tumor cell growth. In vivo tumor modeling studies with a highly metastatic tumor line, PC-3ML cells, revealed that EGCG (228 mg/kg or 200 μmol/L) appeared to sensitize tumors to Dox. EGCG combined with low levels of Dox (0.14 mg/kg or 2 μmol/L) blocked tumor growth by PC-3ML cells injected intraperitoneally (ie, in CB17 severe combined immunodeficiencies) and significantly increased mouse survival rates. Similarly, relatively low levels of EGCG (57 mg/kg or 50 μmol/L) plus Dox (0.07 mg/kg or 1 μmol/L) eradicated established tumors (ie, in nonobese diabetic–severe combined immunodeficiencies) that were derived from CD44hi tumor-initiating cells isolated from PCa-20a cells. Flow cytometry results showed that EGCG appeared to enhance retention of Dox by tumor cells to synergistically inhibit tumor growth and eradicate tumors. These data suggest that localized delivery of high dosages of EGCG combined with low levels of Dox may have significant clinical application in the treatment of metastatic prostate and/or eradication of primary tumors derived from tumor-initiating cells. PMID:20971741

  20. Modeling Breast Tumor Development with a Humanized Mouse Model.

    PubMed

    Arendt, Lisa M

    2016-01-01

    The tumor microenvironment plays a critical role in breast cancer growth and progression to metastasis. Here, we describe a method to examine stromal-epithelial interactions during tumor formation and progression utilizing human-derived mammary epithelial cells and breast stromal cells. This method outlines the isolation of each cell type from reduction mammoplasty tissue, the culture and genetic modification of both epithelial and stromal cells using lentiviral technology, and the method of humanizing and implantation of transformed epithelial cells into the cleared mammary fat pads of immunocompromised mice. This model system may be a useful tool to dissect signaling interactions that contribute to invasive tumor behavior and therapeutic resistance. PMID:27581027

  1. Recent advances in managing human papillomavirus-positive oropharyngeal tumors

    PubMed Central

    Riccio, Stefano; Colombo, Sarah; Pompilio, Madia; Formillo, Paolo

    2010-01-01

    Human papillomavirus (HPV) is detected in a subset of patients with head and neck squamous cell carcinoma, most frequently in tumors in the Waldeyer's ring (palatine tonsil and base of tongue). Several studies suggest that patients with HPV-positive tumors have better survival with either concurrent chemoradiation therapy or surgery followed by radiation compared with HPV-negative patients. However, some possible confounding clinicopathologic variables may challenge the validity of this statement, for example, some authors used the TNM (tumor, node, metastasis) grouping stage while others used the primary tumor (T stage), and other studies have demonstrated that tumors with advanced T stage were less likely to be infected with HPV. A large clinical trial with stratification of patients according to all known tumor prognostic factors is crucial to solve the question. PMID:20948869

  2. The YSNSG cyclopeptide derived from tumstatin inhibits tumor angiogenesis by down-regulating endothelial cell migration.

    PubMed

    Thevenard, Jessica; Ramont, Laurent; Devy, Jérome; Brassart, Bertrand; Dupont-Deshorgue, Aurélie; Floquet, Nicolas; Schneider, Laurence; Ouchani, Farid; Terryn, Christine; Maquart, François-Xavier; Monboisse, Jean-Claude; Brassart-Pasco, Sylvie

    2010-03-01

    We previously demonstrated that the CNYYSNS peptide derived from tumstatin inhibited in vivo tumor progression. The YSNS motif formed a beta-turn crucial for biological activity. More recently, a YSNSG cyclopeptide with a constrained beta-turn on the YSNS residues was designed. Intraperitoneal administration of the YSNSG cyclopeptide inhibited in vivo melanoma progression more efficiently than the native linear peptide. In the present article, we showed that the YSNSG cyclopeptide also triggered an inhibition of in vivo tumor neovascularization and we further analyzed its in vitroantiangiogenic effect. The YSNSG cyclopeptide did not alter endothelial cell proliferation but inhibited cell migration by 83% in an in vitro wound healing model. The inhibition was mediated by a decrease in active MT1-MMP at the migration front as well as a decrease in u-PA and u-PAR expression. The cyclopeptide also altered beta1-integrin distribution in endothelial cell lamellipodia, induced a strong decrease in the phosphorylated focal adhesion kinase (p125(FAK)), disorganized F-actin stress fibers and decreased the number of lamellipodia, resulting in a non migratory phenotype. Our results confirm the YSNSG cyclopeptide as a potent antitumor agent, through both the inhibition of invasive properties of tumor cells and the antiangiogenic activity. PMID:19551865

  3. Chloroquine alleviates etoposide-induced centrosome amplification by inhibiting CDK2 in adrenocortical tumor cells

    PubMed Central

    Chen, T-Y; Syu, J-S; Lin, T-C; Cheng, H-l; Lu, F-l; Wang, C-Y

    2015-01-01

    The antitumor drug etoposide (ETO) is widely used in treating several cancers, including adrenocortical tumor (ACT). However, when used at sublethal doses, tumor cells still survive and are more susceptible to the recurring tumor due to centrosome amplification. Here, we checked the effect of sublethal dose of ETO in ACT cells. Sublethal dose of ETO treatment did not induce cell death but arrested the ACT cells in G2/M phase. This resulted in centrosome amplification and aberrant mitotic spindle formation leading to genomic instability and cellular senescence. Under such conditions, Chk2, cyclin A/CDK2 and ERK1/2 were aberrantly activated. Pharmacological inactivation of Chk2, CDK2 or ERK1/2 or depletion of CDK2 or Chk2 inhibited the centrosome amplification in ETO-treated ACT cells. In addition, autophagy was activated by ETO and was required for ACT cell survival. Chloroquine, the autophagy inhibitor, reduced ACT cell growth and inhibited ETO-induced centrosome amplification. Chloroquine alleviated CDK2 and ERK, but not Chk2, activation and thus inhibited centrosome amplification in either ETO- or hydroxyurea-treated ACT cells. In addition, chloroquine also inhibited centrosome amplification in osteosarcoma U2OS cell lines when treated with ETO or hydroxyurea. In summary, we have demonstrated that chloroquine inhibited ACT cell growth and alleviated DNA damage-induced centrosome amplification by inhibiting CDK2 and ERK activity, thus preventing genomic instability and recurrence of ACT. PMID:26690546

  4. A small-molecule antagonist of CXCR4 inhibits intracranial growth of primary brain tumors

    NASA Astrophysics Data System (ADS)

    Rubin, Joshua B.; Kung, Andrew L.; Klein, Robyn S.; Chan, Jennifer A.; Sun, Yanping; Schmidt, Karl; Kieran, Mark W.; Luster, Andrew D.; Segal, Rosalind A.

    2003-11-01

    The vast majority of brain tumors in adults exhibit glial characteristics. Brain tumors in children are diverse: Many have neuronal characteristics, whereas others have glial features. Here we show that activation of the Gi protein-coupled receptor CXCR4 is critical for the growth of both malignant neuronal and glial tumors. Systemic administration of CXCR4 antagonist AMD 3100 inhibits growth of intracranial glioblastoma and medulloblastoma xenografts by increasing apoptosis and decreasing the proliferation of tumor cells. This reflects the ability of AMD 3100 to reduce the activation of extracellular signal-regulated kinases 1 and 2 and Akt, all of which are pathways downstream of CXCR4 that promote survival, proliferation, and migration. These studies (i) demonstrate that CXCR4 is critical to the progression of diverse brain malignances and (ii) provide a scientific rationale for clinical evaluation of AMD 3100 in treating both adults and children with malignant brain tumors.

  5. Inhibition of vacuolar ATPase subunit in tumor cells delays tumor growth by decreasing the essential macrophage population in the tumor microenvironment.

    PubMed

    Katara, G K; Kulshrestha, A; Jaiswal, M K; Pamarthy, S; Gilman-Sachs, A; Beaman, K D

    2016-02-25

    In cancer cells, vacuolar ATPase (V-ATPase), a multi-subunit enzyme, is expressed on the plasma as well as vesicular membranes and critically influences metastatic behavior. The soluble, cleaved N-terminal domain of V-ATPase a2 isoform is associated with in vitro induction of tumorigenic characteristics in macrophages. This activity led us to further investigate its in vivo role in cancer progression by inhibition of a2 isoform (a2V) in tumor cells and the concomitant effect on tumor microenvironment in the mouse 4T-1 breast cancer model. Results showed that macrophages cocultivated with a2V knockdown (sh-a2) 4T-1 cells produce lower amounts of tumorigenic factors in vitro and have reduced ability to suppress T-cell activation and proliferation compared with control 4T-1 cells. Data analysis showed a delayed mammary tumor growth in Balb/c mice inoculated with sh-a2 4T-1 cells compared with control. The purified CD11b(+) macrophages from sh-a2 tumors showed a reduced expression of mannose receptor-1 (CD206), interleukin-10, transforming growth factor-β, arginase-1, matrix metalloproteinase and vascular endothelial growth factor. Flow cytometric analysis of tumor-infiltrated macrophages showed a significantly low number of F4/80(+)CD11c(+)CD206(+) macrophages in sh-a2 tumors compared with control. In sh-a2 tumors, most of the macrophages were F4/80(+)CD11c(+) (antitumor M1 macrophages) suggesting it to be the reason behind delayed tumor growth. Additionally, tumor-infiltrating macrophages from sh-a2 tumors showed a reduced expression of CD206 compared with control whereas CD11c expression was unaffected. These findings demonstrate that in the absence of a2V in tumor cells, the resident macrophage population in the tumor microenvironment is altered which affects in vivo tumor growth. We suggest that by involving the host immune system, tumor growth can be controlled through targeting of a2V on tumor cells. PMID:25961933

  6. Arsenic trioxide disrupts glioma stem cells via promoting PML degradation to inhibit tumor growth

    PubMed Central

    Zhou, Wenchao; Cheng, Lin; Shi, Yu; Ke, Susan Q.; Huang, Zhi; Fang, Xiaoguang; Chu, Cheng-wei; Xie, Qi; Bian, Xiu-wu; Rich, Jeremy N.; Bao, Shideng

    2015-01-01

    Glioblastoma multiforme (GBM) is the most lethal brain tumor. Tumor relapse in GBM is inevitable despite maximal therapeutic interventions. Glioma stem cells (GSCs) have been found to be critical players in therapeutic resistance and tumor recurrence. Therapeutic drugs targeting GSCs may significantly improve GBM treatment. In this study, we demonstrated that arsenic trioxide (As2O3) effectively disrupted GSCs and inhibited tumor growth in the GSC-derived orthotopic xenografts by targeting the promyelocytic leukaemia (PML). As2O3 treatment induced rapid degradation of PML protein along with severe apoptosis in GSCs. Disruption of the endogenous PML recapitulated the inhibitory effects of As2O3 treatment on GSCs both in vitro and in orthotopic tumors. Importantly, As2O3 treatment dramatically reduced GSC population in the intracranial GBM xenografts and increased the survival of mice bearing the tumors. In addition, As2O3 treatment preferentially inhibited cell growth of GSCs but not matched non-stem tumor cells (NSTCs). Furthermore, As2O3 treatment or PML disruption potently diminished c-Myc protein levels through increased poly-ubiquitination and proteasome degradation of c-Myc. Our study indicated a potential implication of As2O3 in GBM treatment and highlighted the important role of PML/c-Myc axis in the maintenance of GSCs. PMID:26510911

  7. Dihydrolipoic acid inhibits tetrachlorohydroquinone-induced tumor promotion through prevention of oxidative damage.

    PubMed

    Wang, Ying-Jan; Yang, Ming-Chen; Pan, Ming-Hsiung

    2008-12-01

    alpha-Lipoic acid (LA) has been intensely investigated as a therapeutic agent for several diseases, including hepatic disorder and diabetic polyneuropathy. However, the effects of LA or its reduced form, dihydrolipoic acid (DHLA), on cancer chemoprevention has seldom been studied. Tetrachlorohydroquinone (TCHQ) is a toxic metabolite of pentachlorophenol (PCP) that was proven to be a tumor promoter in our previous study. We recently reported that DHLA can inhibit DMBA/TPA-induced skin tumor formation through its anti-inflammatory and anti-oxidizing functions. In the present study, we further examined the effects of DHLA on DMBA/TCHQ-induced skin tumor formation and the possible mechanisms. We found that DHLA significantly inhibited tumor incidence and tumor multiplicity in DMBA/TCHQ-induced skin tumor formation. Administration of DHLA prevented ROS generation, cytotoxicity, genotoxicity and apoptotic cell death in cells treated with TCHQ. In addition, activation of JNK and p38 MAPK may be involved in TCHQ-mediated apoptosis. Nonetheless, the detailed mechanisms of DHLA in attenuating TCHQ-induced skin tumor promotion are still unclear and need to be further investigated. We conclude that DHLA may be a useful protective agent against TCHQ-induced toxicity in epithelial cells, and for reversing TCHQ-induced damage in mouse skin. PMID:18951944

  8. Inhibitor or promoter? The performance of polysaccharides from Ganoderma lucidum on human tumor cells with different p53 statuses.

    PubMed

    Zhang, Jue; Chen, Jun-ming; Wang, Xiao-xia; Xia, Yong-mei; Cui, Steve W; Li, Jian; Ding, Zhong-yang

    2016-04-01

    Polysaccharides from Ganoderma lucidum (GLPs) have been taken as effective supplements by both healthy people and cancer patients for many years. However, this short survey indicates that instead of inhibiting cancer cell growth, both submerge-cultured intracellular GLP and fruiting body GLP can stimulate the growth of human carcinoma cell lines lacking functional p53, such as HCT-116 p53(-/-), Saos-2, H1299, HL-60, MDA-MB-157. Conversely, the two GLPs inhibit all other assayed cells with functional p53. These results could be an alert since mutational inactivation of the tumor suppressor protein p53 is the most frequent genetic alteration found in human tumors. PMID:26999513

  9. Warburg metabolism in tumor-conditioned macrophages promotes metastasis in human pancreatic ductal adenocarcinoma.

    PubMed

    Penny, Hweixian Leong; Sieow, Je Lin; Adriani, Giulia; Yeap, Wei Hseun; See Chi Ee, Peter; San Luis, Boris; Lee, Bernett; Lee, Terence; Mak, Shi Ya; Ho, Ying Swan; Lam, Kong Peng; Ong, Choon Kiat; Huang, Ruby Y J; Ginhoux, Florent; Rotzschke, Olaf; Kamm, Roger D; Wong, Siew Cheng

    2016-08-01

    Patients with pancreatic ductal adenocarcinoma (PDAC) face a clinically intractable disease with poor survival rates, attributed to exceptionally high levels of metastasis. Epithelial-to-mesenchymal transition (EMT) is pronounced at inflammatory foci within the tumor; however, the immunological mechanisms promoting tumor dissemination remain unclear. It is well established that tumors exhibit the Warburg effect, a preferential use of glycolysis for energy production, even in the presence of oxygen, to support rapid growth. We hypothesized that the metabolic pathways utilized by tumor-infiltrating macrophages are altered in PDAC, conferring a pro-metastatic phenotype. We generated tumor-conditioned macrophages in vitro, in which human peripheral blood monocytes were cultured with conditioned media generated from normal pancreatic or PDAC cell lines to obtain steady-state and tumor-associated macrophages (TAMs), respectively. Compared with steady-state macrophages, TAMs promoted vascular network formation, augmented extravasation of tumor cells out of blood vessels, and induced higher levels of EMT. TAMs exhibited a pronounced glycolytic signature in a metabolic flux assay, corresponding with elevated glycolytic gene transcript levels. Inhibiting glycolysis in TAMs with a competitive inhibitor to Hexokinase II (HK2), 2-deoxyglucose (2DG), was sufficient to disrupt this pro-metastatic phenotype, reversing the observed increases in TAM-supported angiogenesis, extravasation, and EMT. Our results indicate a key role for metabolic reprogramming of tumor-infiltrating macrophages in PDAC metastasis, and highlight the therapeutic potential of using pharmacologics to modulate these metabolic pathways. PMID:27622062

  10. Endoglin targeting inhibits tumor angiogenesis and metastatic spread in breast cancer.

    PubMed

    Paauwe, M; Heijkants, R C; Oudt, C H; van Pelt, G W; Cui, C; Theuer, C P; Hardwick, J C H; Sier, C F M; Hawinkels, L J A C

    2016-08-01

    Endoglin, a transforming growth factor-β co-receptor, is highly expressed on angiogenic endothelial cells in solid tumors. Therefore, targeting endoglin is currently being explored in clinical trials for anti-angiogenic therapy. In this project, the redundancy between endoglin and vascular endothelial growth factor (VEGF) signaling in angiogenesis and the effects of targeting both pathways on breast cancer metastasis were explored. In patient samples, increased endoglin signaling after VEGF inhibition was observed. In vitro TRC105, an endoglin-neutralizing antibody, increased VEGF signaling in endothelial cells. Moreover, combined targeting of the endoglin and VEGF pathway, with the VEGF receptor kinase inhibitor SU5416, increased antiangiogenic effects in vitro and in a zebrafish angiogenesis model. Next, in a mouse model for invasive lobular breast cancer, the effects of TRC105 and SU5416 on tumor growth and metastasis were explored. Although TRC105 and SU5416 decreased tumor vascular density, tumor volume was unaffected. Strikingly, in mice treated with TRC105, or TRC105 and SU5416 combined, a strong inhibition in the number of metastases was seen. Moreover, upon resection of the primary tumor, strong inhibition of metastatic spread by TRC105 was observed in an adjuvant setting. To confirm these data, we assessed the effects of endoglin-Fc (an endoglin ligand trap) on metastasis formation. Similar to treatment with TRC105 in the resection model, endoglin-Fc-expressing tumors showed strong inhibition of distant metastases. These results show, for the first time, that targeting endoglin, either with neutralizing antibodies or a ligand trap, strongly inhibits metastatic spread of breast cancer in vivo. PMID:26804178

  11. Luteolin inhibits the Nrf2 signaling pathway and tumor growth in vivo

    SciTech Connect

    Chian, Song; Thapa, Ruby; Chi, Zhexu; Wang, Xiu Jun; Tang, Xiuwen

    2014-05-16

    Highlights: • Luteolin inhibits the Nrf2 pathway in mouse liver and in xenografted tumors. • Luteolin markedly inhibits the growth of xenograft tumors. • Luteolin enhances the anti-cancer effect of cisplatin in mice in vivo. • Luteolin could serve as an adjuvant in the chemotherapy of NSCLC. - Abstract: Nuclear factor erythroid 2-related factor 2 (Nrf2) is over-expressed in many types of tumor, promotes tumor growth, and confers resistance to anticancer therapy. Hence, Nrf2 is regarded as a novel therapeutic target in cancer. Previously, we reported that luteolin is a strong inhibitor of Nrf2 in vitro. Here, we showed that luteolin reduced the constitutive expression of NAD(P)H quinone oxidoreductase 1 in mouse liver in a time- and dose-dependent manner. Further, luteolin inhibited the expression of antioxidant enzymes and glutathione transferases, decreasing the reduced glutathione in the liver of wild-type mice under both constitutive and butylated hydroxyanisole-induced conditions. In contrast, such distinct responses were not detected in Nrf2{sup −/−} mice. In addition, oral administration of luteolin, either alone or combined with intraperitoneal injection of the cytotoxic drug cisplatin, greatly inhibited the growth of xenograft tumors from non-small-cell lung cancer (NSCLC) cell line A549 cells grown subcutaneously in athymic nude mice. Cell proliferation, the expression of Nrf2, and antioxidant enzymes were all reduced in tumor xenograft tissues. Furthermore, luteolin enhanced the anti-cancer effect of cisplatin. Together, our findings demonstrated that luteolin inhibits the Nrf2 pathway in vivo and can serve as an adjuvant in the chemotherapy of NSCLC.

  12. Tumor necrosis factor-beta in human pregnancy and labor.

    PubMed

    Laham, N; Van Dunné, F; Abraham, L J; Farrugia, W; Bendtzen, K; Brennecke, S P; Rice, G E

    1997-04-01

    The aims of this study were to determine tumor necrosis factor-beta (TNF-beta) concentration profiles in peripheral venous plasma and amniotic fluid during pregnancy and at the time of labor and to characterise TNF-beta mRNA expression and TNF-beta release from human gestational tissues. In addition, we investigated the expression of TNF-beta binding protein, lymphotoxin-beta (LT-beta), in human gestational tissues. The mean (+/-S.E.M.) TNF-beta concentrations in maternal plasma (TIL, 78 +/- 12 pg/ml, n = 7 vs. TNIL, 304 +/- 88 pg/ml, n = 7) and amniotic fluid (TIL, 8 +/- 5 pg/ml, n = 6 vs. TNIL, 73 +/- 20 pg/ml, n = 20) were significantly (P < 0.05) decreased in association with term labor-onset (TIL) compared to term not-in-labor (TNIL). TNF-beta concentration in maternal plasma and amniotic fluid did not change significantly either with preterm labor (PIL), or during pregnancy. Group-matched comparison of maternal plasma and amniotic fluid TNF-beta concentrations demonstrated that amniotic fluid TNF-beta concentrations were 6-8 fold lower than maternal plasma TNF-beta concentrations. Furthermore, no detectable TNF-beta was secreted from cultured human amniotic, choriodecidual and placental explants. Although, TNF-beta mRNA was detected in amnion, choriodecidual and placenta, LT-beta was similarly expressed in these tissues, suggesting that TNF-beta may be cell membrane bound. These data demonstrate that TNF-beta is present at low levels within the intrauterine environment and may suggest that TNF-beta is specifically inhibited at the maternal-fetal interface. PMID:9185077

  13. Resistance to telomerase inhibition by human squamous cell carcinoma cell lines.

    PubMed

    Bojovic, Bojana; Crowe, David L

    2011-04-01

    Telomeres are nucleoprotein structures at the ends of chromosomes that are composed of a repetitive G rich sequence and telomeric binding proteins. Telomeres prevent the degradation of chromosomal ends and protect against inappropriate recombination. Telomere attrition involves a tumor suppressor pathway that limits the replication of premalignant cells. The loss of telomeric DNA with each round of replication leads to growth arrest accompanied by senescence or apoptosis. Many tumor cells activate the telomerase gene to bypass senescence. Telomerase is a multisubunit ribonucleoprotein that uses an RNA template to catalyze the addition of telomeric DNA to chromosomal ends. Overexpression of the TERT subunit leads to telomere lengthening and extension of the replicative lifespan. Dominant-negative telomerase has been shown to inhibit telomerase activity in many tumor cell lines, and this is associated with telomere shortening and apoptosis. Additionally, pharmacological telomerase inhibitors have been developed which lead to progressive telomere shortening and programmed cell death. In this study, we report a series of human squamous cell carcinoma cell lines that have high telomerase activity and short telomeres. Dominant-negative telomerase expression and pharmacological telomerase inhibition failed to completely inhibit enzymatic activity which was accompanied by the lack of telomere shortening. These cells continued to proliferate and demonstrated fewer responsive genes when treated with a pharmacological telomerase inhibitor. We concluded that some human squamous cell carcinoma cell lines are resistant to telomerase inhibition. PMID:21305252

  14. Metformin impairs Rho GTPase signaling to induce apoptosis in neuroblastoma cells and inhibits growth of tumors in the xenograft mouse model of neuroblastoma

    PubMed Central

    Kumar, Ambrish; Al-Sammarraie, Nadia; DiPette, Donald J.; Singh, Ugra S.

    2014-01-01

    Metformin has been shown to inhibit tumor growth in xenograft rodent models of adult cancers, and various human clinical trials are in progress. However, the precise molecular mechanisms of metformin action are largely unknown. In the present study we examined the anti-tumor activity of metformin against neuroblastoma, and determined the underlying signaling mechanisms. Using human neuroblastoma xenograft mice, we demonstrated that oral administration of metformin (100 and 250 mg/kg body weight) significantly inhibited the growth of tumors. The interference of metformin in spheroid formation further confirmed the anti-tumor activity of metformin. In tumors, the activation of Rac1 (GTP-Rac1) and Cdc42 (GTP-Cdc42) was increased while RhoA activation (GTP-RhoA) was decreased by metformin. It also induced phosphorylation of JNK and inhibited the phosphorylation of ERK1/2 without affecting p38 MAP Kinase. Infection of cells by adenoviruses expressing dominant negative Rac1 (Rac1-N17), Cdc42 (Cdc42-N17) or constitutively active RhoA (RhoA-V14), or incubation of cells with pharmacological inhibitors of Rac1 (NSC23766) or Cdc42 (ML141) significantly protected neuroblastoma cells from metformin-induced apoptosis. Additionally, inhibition of JNK activity along with Rac1 or Cdc42 attenuated cytotoxic effects of metformin. These studies demonstrated that metformin impairs Rho GTPases signaling to induce apoptosis via JNK pathway. PMID:25365944

  15. Selective expression of constitutively active pro-apoptotic protein BikDD gene in primary mammary tumors inhibits tumor growth and reduces tumor initiating cells

    PubMed Central

    Rahal, Omar M; Nie, Lei; Chan, Li-Chuan; Li, Chia-Wei; Hsu, Yi-Hsin; Hsu, Jennifer; Yu, Dihua; Hung, Mien-Chie

    2015-01-01

    Our previous study showed that specifically delivering BikDD, a constitutive active mutant of pro-apoptotic protein Bik, to breast cancer cell xenografts in immunocompromised mice has a potent activity against tumor initiating cells (TICs), and that the combination between tyrosine kinase inhibitors (TKI) and BikDD gene therapy yielded synergistic effect on EGFR and HER2 positive breast cancer cells in immunodeficient nude mice. Those encouraging results have allowed us to propose a clinical trial using the liposome-complexing plasmid DNA expressing BikDD gene which has been approved by the NIH RAC Advisory committee. However, it is imperative to test whether systemic delivery of BikDD-expressing plasmid DNAs with liposomes into immunocompetent mice has therapeutic efficacy and tolerable side effects as what we observed in the nude mice model. In this study, we investigated the effects of BikDD gene-therapy on the primary mammary tumors, especially on tumor initiating cells (TICs), of a genetically engineered immunocompetent mouse harboring normal microenvironment and immune response. The effects on TIC population in tumors were determined by FACS analysis with different sets of murine specific TIC markers, CD49fhighCD61high and CD24+Jagged1-. First we showed in vitro that ectopic expression of BikDD in murine N202 cells derived from MMTV-HER2/Neu transgenic mouse tumors induced apoptosis and decreased the number of TICs. Consistently, systemic delivery of VISA-Claudin4-BikDD by liposome complexes significantly inhibited mammary tumor growth and slowed down residual tumor growth post cessation of therapy in MMTV-HER2/Neu transgenic mice compared to the controls. In addition, the anti-tumor effects of BikDD in vivo were consistent with decreased TIC population assessed by FACS analysis and in vitro tumorsphere formation assay of freshly isolated tumor cells. Importantly, systemic administration of BikDD did not cause significant cytotoxic response in standard

  16. Selective expression of constitutively active pro-apoptotic protein BikDD gene in primary mammary tumors inhibits tumor growth and reduces tumor initiating cells.

    PubMed

    Rahal, Omar M; Nie, Lei; Chan, Li-Chuan; Li, Chia-Wei; Hsu, Yi-Hsin; Hsu, Jennifer; Yu, Dihua; Hung, Mien-Chie

    2015-01-01

    Our previous study showed that specifically delivering BikDD, a constitutive active mutant of pro-apoptotic protein Bik, to breast cancer cell xenografts in immunocompromised mice has a potent activity against tumor initiating cells (TICs), and that the combination between tyrosine kinase inhibitors (TKI) and BikDD gene therapy yielded synergistic effect on EGFR and HER2 positive breast cancer cells in immunodeficient nude mice. Those encouraging results have allowed us to propose a clinical trial using the liposome-complexing plasmid DNA expressing BikDD gene which has been approved by the NIH RAC Advisory committee. However, it is imperative to test whether systemic delivery of BikDD-expressing plasmid DNAs with liposomes into immunocompetent mice has therapeutic efficacy and tolerable side effects as what we observed in the nude mice model. In this study, we investigated the effects of BikDD gene-therapy on the primary mammary tumors, especially on tumor initiating cells (TICs), of a genetically engineered immunocompetent mouse harboring normal microenvironment and immune response. The effects on TIC population in tumors were determined by FACS analysis with different sets of murine specific TIC markers, CD49f(high)CD61(high) and CD24(+)Jagged1(-). First we showed in vitro that ectopic expression of BikDD in murine N202 cells derived from MMTV-HER2/Neu transgenic mouse tumors induced apoptosis and decreased the number of TICs. Consistently, systemic delivery of VISA-Claudin4-BikDD by liposome complexes significantly inhibited mammary tumor growth and slowed down residual tumor growth post cessation of therapy in MMTV-HER2/Neu transgenic mice compared to the controls. In addition, the anti-tumor effects of BikDD in vivo were consistent with decreased TIC population assessed by FACS analysis and in vitro tumorsphere formation assay of freshly isolated tumor cells. Importantly, systemic administration of BikDD did not cause significant cytotoxic response in

  17. Inhibition of mammary tumor growth and metastases to bone and liver by dietary grape polyphenols.

    PubMed

    Castillo-Pichardo, Linette; Martínez-Montemayor, Michelle M; Martínez, Joel E; Wall, Kristin M; Cubano, Luis A; Dharmawardhane, Suranganie

    2009-01-01

    The cancer preventive properties of grape products such as red wine have been attributed to polyphenols enriched in red wine. However, much of the studies on cancer preventive mechanisms of grape polyphenols have been conducted with individual compounds at concentrations too high to be achieved via dietary consumption. We recently reported that combined grape polyphenols at physiologically relevant concentrations are more effective than individual compounds at inhibition of ERalpha(-), ERbeta(+) MDA-MB-231 breast cancer cell proliferation, cell cycle progression, and primary mammary tumor growth (Schlachterman et al., Transl Oncol 1:19-27, 2008). Herein, we show that combined grape polyphenols induce apoptosis and are more effective than individual resveratrol, quercetin, or catechin at inhibition of cell proliferation, cell cycle progression, and cell migration in the highly metastatic ER (-) MDA-MB-435 cell line. The combined effect of dietary grape polyphenols (5 mg/kg each resveratrol, quercetin, and catechin) was tested on progression of mammary tumors in nude mice created from green fluorescent protein-tagged MDA-MB-435 bone metastatic variant. Fluorescence image analysis of primary tumor growth demonstrated a statistically significant decrease in tumor area by dietary grape polyphenols. Molecular analysis of excised tumors demonstrated that reduced mammary tumor growth may be due to upregulation of FOXO1 (forkhead box O1) and NFKBIA (IkappaBalpha), thus activating apoptosis and potentially inhibiting NfkappaB (nuclear factor kappaB) activity. Image analysis of distant organs for metastases demonstrated that grape polyphenols reduced metastasis especially to liver and bone. Overall, these results indicate that combined dietary grape polyphenols are effective at inhibition of mammary tumor growth and site-specific metastasis. PMID:19294520

  18. Cytosolic phospholipaseA2 inhibition with PLA-695 radiosensitizes tumors in lung cancer animal models.

    PubMed

    Thotala, Dinesh; Craft, Jeffrey M; Ferraro, Daniel J; Kotipatruni, Rama P; Bhave, Sandeep R; Jaboin, Jerry J; Hallahan, Dennis E

    2013-01-01

    Lung cancer remains the leading cause of cancer deaths in the United States and the rest of the world. The advent of molecularly directed therapies holds promise for improvement in therapeutic efficacy. Cytosolic phospholipase A2 (cPLA2) is associated with tumor progression and radioresistance in mouse tumor models. Utilizing the cPLA2 specific inhibitor PLA-695, we determined if cPLA2 inhibition radiosensitizes non small cell lung cancer (NSCLC) cells and tumors. Treatment with PLA-695 attenuated radiation induced increases of phospho-ERK and phospho-Akt in endothelial cells. NSCLC cells (LLC and A549) co-cultured with endothelial cells (bEND3 and HUVEC) and pre-treated with PLA-695 showed radiosensitization. PLA-695 in combination with irradiation (IR) significantly reduced migration and proliferation in endothelial cells (HUVEC & bEND3) and induced cell death and attenuated invasion by tumor cells (LLC &A549). In a heterotopic tumor model, the combination of PLA-695 and radiation delayed growth in both LLC and A549 tumors. LLC and A549 tumors treated with a combination of PLA-695 and radiation displayed reduced tumor vasculature. In a dorsal skin fold model of LLC tumors, inhibition of cPLA2 in combination with radiation led to enhanced destruction of tumor blood vessels. The anti-angiogenic effects of PLA-695 and its enhancement of the efficacy of radiotherapy in mouse models of NSCLC suggest that clinical trials for its capacity to improve radiotherapy outcomes are warranted. PMID:23894523

  19. Cytosolic PhospholipaseA2 Inhibition with PLA-695 Radiosensitizes Tumors in Lung Cancer Animal Models