Use of polyclonal/monoclonal antibody therapies in transplantation.

PubMed

Yeung, Melissa Y; Gabardi, Steven; Sayegh, Mohamed H

2017-03-01

For over thirty years, antibody (mAb)-based therapies have been a standard component of transplant immunosuppression, and yet much remains to be learned in order for us to truly harness their therapeutic capabilities. Current mAbs used in transplant directly target and destroy graft-destructive immune cells, interrupt cytokine and costimulation-dependent T and B cell activation, and prevent down-stream complement activation. Areas covered: This review summarizes our current approaches to using antibody-based therapies to prevent and treat allograft rejection. It also provides examples of promising novel mAb therapies, and discusses the potential for future mAb development in transplantation. Expert opinion: The broad capability of antibodies, in parallel with our growing ability to synthetically modulate them, offers exciting opportunities to develop better biologic therapeutics. In order to do so, we must further our understanding about the basic biology underlying allograft rejection, and gain better appreciation of how characteristics of therapeutic antibodies affect their efficacy.

Extracorporeal adsorption therapy: A Method to improve targeted radiation delivered by radiometal-labeled monoclonal antibodies.

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

Nemecek, Eneida R.; Green, Damian J.; Fisher, Darrell R.

2008-04-01

Many investigators have demonstrated the ability to treat hematologic malignancies with radiolabeled monoclonal antibodies targeting hematopoietic antigens such as anti-CD20 and anti-CD45. [1-5] Although the remission rates achieved with radioimmunotherapy (RIT) are relatively high, many patients subsequently relapse presumably due to suboptimal delivery of enough radiation to eradicate the malignancy. The dose-response of leukemia and lymphoma to radiation has been proven. Substantial amounts of radiation can be delivered by RIT if followed by hematopoietic cell transplantation to rescue the bone marrow from myeloablation.[ref] However, the maximum dose of RIT that can be used is still limited by toxicity to normalmore » tissues affected by nonspecific delivery of radiation. Efforts to improve RIT focus on improving the therapeutic ratios of radiation in target versus non-target tissues by removing the fraction of radioisotope that fails to bind to target tissues and circulates freely in the bloodstream perfusing non-target tissues. Our group and others have explored several alternatives for removal of unbound circulating antibody. [refs] One such method, extracorporeal adsorption therapy (ECAT) consists of removing unbound antibody by a method similar to plasmapheresis after critical circulation time and distribution of antibody into target tissues have been achieved. Preclinical studies of ECAT in murine xenograft models demonstrated significant improvement in therapeutic ratios of radioactivity. Chen and colleagues demonstrated that a 2-hour ECAT procedure could remove 40 to 70% of the radioactivity from liver, lung and spleen. [ref] Although isotope concentration in the tumor was initially unaffected, a 50% decrease was noted approximately 36 hours after the procedure. This approach was also evaluated in a limited phase I pilot study of patients with refractory B-cell lymphoma. [ref] After radiographic confirmation of tumor localization of a test dose of

Design of therapeutic vaccines as a novel antibody therapy for cardiovascular diseases.

PubMed

Nakagami, Hironori

2017-09-01

Vaccines are primarily used worldwide as a preventive medicine for infectious diseases and have recently been applied to cancer. We and others have developed therapeutic vaccines designed for cardiovascular diseases that are notably different from previous vaccines. In the case of cancer vaccines, a specific protein in cancer cells is a target antigen, and the activation of cytotoxic T cells (CTL) is required to kill and remove the antigen-presenting cancer cells. Our therapeutic vaccines work against hypertension by targeting angiotensin II (Ang II) as the antigen, which is an endogenous hormone. Therapeutic vaccines must avoid CTL activation and induce the blocking antibodies for Ang II. The goal of our therapeutic vaccine for cardiovascular diseases is to induce the specific antibody response toward the target protein without inducing T-cell or antibody-mediated inflammation through the careful selection of the target antigen, carrier protein and adjuvants. The goal of our therapeutic vaccine is similar to that of antibody therapy. Recently, multiple antibody-based drugs have been developed for cancer, immune-related diseases, and dyslipidemia, which are efficient but expensive. If the effect of a therapeutic vaccine is nearly equivalent to antibody therapy as an alternative approach, the lower medical cost and improvement in drug adherence can be advantages of therapeutic vaccines. In this review, we will describe our concept of therapeutic vaccines for cardiovascular diseases and the future directions of therapeutic vaccines as novel antibody therapies. Copyright © 2017. Published by Elsevier Ltd.

Challenges and opportunities for monoclonal antibody therapy in veterinary oncology.

PubMed

Beirão, Breno C B; Raposo, Teresa; Jain, Saurabh; Hupp, Ted; Argyle, David J

2016-12-01

Monoclonal antibodies (mAbs) have come to dominate the biologics market in human cancer therapy. Nevertheless, in veterinary medicine, very few clinical trials have been initiated using this form of therapy. Some of the advantages of mAb therapeutics over conventional drugs are high specificity, precise mode of action and long half-life, which favour infrequent dosing of the antibody. Further advancement in the field of biomedical sciences has led to the production of different forms of antibodies, such as single chain antibody fragment, Fab, bi-specific antibodies and drug conjugates for use in diagnostic and therapeutic purposes. This review describes the potential for mAbs in veterinary oncology in supporting both diagnosis and therapy of cancer. The technical and financial hurdles to facilitate clinical acceptance of mAbs are explored and insights into novel technologies and targets that could support more rapid clinical development are offered. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phosphatidylserine-targeting antibodies augment the anti-tumorigenic activity of anti-PD-1 therapy by enhancing immune activation and downregulating pro-oncogenic factors induced by T-cell checkpoint inhibition in murine triple-negative breast cancers.

PubMed

Gray, Michael J; Gong, Jian; Hatch, Michaela M S; Nguyen, Van; Hughes, Christopher C W; Hutchins, Jeff T; Freimark, Bruce D

2016-05-11

The purpose of this study was to investigate the potential of antibody-directed immunotherapy targeting the aminophospholipid phosphatidylserine, which promotes immunosuppression when exposed in the tumor microenvironment, alone and in combination with antibody treatment towards the T-cell checkpoint inhibitor PD-1 in breast carcinomas, including triple-negative breast cancers. Immune-competent mice bearing syngeneic EMT-6 or E0771 tumors were subjected to treatments comprising of a phosphatidylserine-targeting and an anti-PD-1 antibody either as single or combinational treatments. Anti-tumor effects were determined by tumor growth inhibition and changes in overall survival accompanying each treatment. The generation of a tumor-specific immune response in animals undergoing complete tumor regression was assessed by secondary tumor cell challenge and splenocyte-produced IFNγ in the presence or absence of irradiated tumor cells. Changes in the presence of tumor-infiltrating lymphocytes were assessed by flow cytometry, while mRNA-based immune profiling was determined using NanoString PanCancer Immune Profiling Panel analysis. Treatment by a phosphatidylserine-targeting antibody inhibits in-vivo growth and significantly enhances the anti-tumor activity of antibody-mediated PD-1 therapy, including providing a distinct survival advantage over treatment by either single agent. Animals in which complete tumor regression occurred with combination treatments were resistant to secondary tumor challenge and presented heightened expression levels of splenocyte-produced IFNγ. Combinational treatment by a phosphatidylserine-targeting antibody with anti-PD-1 therapy increased the number of tumor-infiltrating lymphocytes more than that observed with single-arm therapies. Finally, immunoprofiling analysis revealed that the combination of anti-phosphatidylserine targeting antibody and anti-PD-1 therapy enhanced tumor-infiltrating lymphocytes, and increased expression of pro

Macrophages are critical effectors of antibody therapies for cancer.

PubMed

Weiskopf, Kipp; Weissman, Irving L

2015-01-01

Macrophages are innate immune cells that derive from circulating monocytes, reside in all tissues, and participate in many states of pathology. Macrophages play a dichotomous role in cancer, where they promote tumor growth but also serve as critical immune effectors of therapeutic antibodies. Macrophages express all classes of Fcγ receptors, and they have immense potential to destroy tumors via the process of antibody-dependent phagocytosis. A number of studies have demonstrated that macrophage phagocytosis is a major mechanism of action of many antibodies approved to treat cancer. Consequently, a number of approaches to augment macrophage responses to therapeutic antibodies are under investigation, including the exploration of new targets and development of antibodies with enhanced functions. For example, the interaction of CD47 with signal-regulatory protein α (SIRPα) serves as a myeloid-specific immune checkpoint that limits the response of macrophages to antibody therapies, and CD47-blocking agents overcome this barrier to augment phagocytosis. The response of macrophages to antibody therapies can also be enhanced with engineered Fc variants, bispecific antibodies, or antibody-drug conjugates. Macrophages have demonstrated success as effectors of cancer immunotherapy, and further investigation will unlock their full potential for the benefit of patients.

Discovery of an antibody for pan-ebolavirus therapy.

PubMed

Furuyama, Wakako; Marzi, Andrea; Nanbo, Asuka; Haddock, Elaine; Maruyama, Junki; Miyamoto, Hiroko; Igarashi, Manabu; Yoshida, Reiko; Noyori, Osamu; Feldmann, Heinz; Takada, Ayato

2016-02-10

During the latest outbreak of Ebola virus disease in West Africa, monoclonal antibody therapy (e.g., ZMapp) was utilized to treat patients. However, due to the antigenic differences among the five ebolavirus species, the current therapeutic monoclonal antibodies are only effective against viruses of the species Zaire ebolavirus. Although this particular species has indeed caused the majority of human infections in Central and, recently, West Africa, other ebolavirus species (e.g., Sudan ebolavirus and Bundibugyo ebolavirus) have also repeatedly caused outbreaks in Central Africa and thus should not be neglected in the development of countermeasures against ebolaviruses. Here we report the generation of an ebolavirus glycoprotein-specific monoclonal antibody that effectively inhibits cellular entry of representative isolates of all known ebolavirus species in vitro and show its protective efficacy in mouse models of ebolavirus infections. This novel neutralizing monoclonal antibody targets a highly conserved internal fusion loop in the glycoprotein molecule and prevents membrane fusion of the viral envelope with cellular membranes. The discovery of this highly cross-neutralizing antibody provides a promising option for broad-acting ebolavirus antibody therapy and will accelerate the design of improved vaccines that can selectively elicit cross-neutralizing antibodies against multiple species of ebolaviruses.

Antibodies Targeting EMT

DTIC Science & Technology

2015-10-01

breast cancer does not have specific antibody drugs like Herceptin, and there is considerable need for targeted therapeutics and diagnostic...mesenchymal transition” or EMT. This process is important in several cancers , but is particularly associated with “triple-negative” breast cancer ...pathways in cancer cells and make a major impact on breast cancer . 15. SUBJECT TERMS Monoclonal Antibody, Epithelial to Mesenchymal Transition, Antibody

Antibody therapy for acute myeloid leukaemia.

PubMed

Gasiorowski, Robin E; Clark, Georgina J; Bradstock, Kenneth; Hart, Derek N J

2014-02-01

Novel therapies with increased efficacy and decreased toxicity are desperately needed for the treatment of acute myeloid leukaemia (AML). The anti CD33 immunoconjugate, gemtuzumab ozogamicin (GO), was withdrawn with concerns over induction mortality and lack of efficacy. However a number of recent trials suggest that, particularly in AML with favourable cytogenetics, GO may improve overall survival. This data and the development of alternative novel monoclonal antibodies (mAb) have renewed interest in the area. Leukaemic stem cells (LSC) are identified as the subset of AML blasts that reproduces the leukaemic phenotype upon transplantation into immunosuppressed mice. AML relapse may be caused by chemoresistant LSC and this has refocused interest on identifying and targeting antigens specific for LSC. Several mAb have been developed that target LSC effectively in xenogeneic models but only a few have begun clinical evaluation. Antibody engineering may improve the activity of potential new therapeutics for AML. The encouraging results seen with bispecific T cell-engaging mAb-based molecules against CD19 in the treatment of B-cell acute lymphobalstic leukaemia, highlight the potential efficacy of engineered antibodies in the treatment of acute leukaemia. Potent engineered mAb, possibly targeting novel LSC antigens, offer hope for improving the current poor prognosis for AML. © 2013 John Wiley & Sons Ltd.

Angiogenic cytokines are antibody targets during graft-versus-leukemia reactions

PubMed Central

Piesche, Matthias; Ho, Vincent T.; Kim, Haesook; Nakazaki, Yukoh; Nehil, Michael; Yaghi, Nasser; Kolodin, Dmitriy; Weiser, Jeremy; Altevogt, Peter; Kiefel, Helena; Alyea, Edwin P.; Antin, Joseph H.; Cutler, Corey; Koreth, John; Canning, Christine; Ritz, Jerome; Soiffer, Robert J.; Dranoff, Glenn

2014-01-01

Purpose The graft-versus-leukemia (GVL) reaction is an important example of immune-mediated tumor destruction. A coordinated humoral and cellular response accomplishes leukemia cell killing, but the specific targets remain largely uncharacterized. To learn more about the antigens that elicit antibodies during GVL reactions, we analyzed advanced myelodysplasia (MDS) and acute myeloid leukemia (AML) patients who received an autologous, granulocyte-macrophage colony stimulating factor (GM-CSF) secreting tumor cell vaccine early after allogeneic hematopoietic stem cell transplantation (HSCT). Experimental Design A combination of tumor-derived cDNA expression library screening, protein microarrays, and antigen-specific ELISAs were employed to characterize sera obtained longitudinally from 15 AML/MDS patients who were vaccinated early after allogeneic HSCT. Results A broad, therapy-induced antibody response was uncovered, which primarily targeted intracellular proteins that function in growth, transcription/translation, metabolism, and homeostasis. Unexpectedly, antibodies were also elicited against eight secreted angiogenic cytokines that play critical roles in leukemogenesis. Antibodies to the angiogenic cytokines were evident early after therapy, and in some patients manifested a diversification in reactivity over time. Patients that developed antibodies to multiple angiogenic cytokines showed prolonged remission and survival. Conclusions These results reveal a potent humoral response during GVL reactions induced with vaccination early after allogeneic HSCT and raise the possibility that antibodies, in conjunction with NK cells and T lymphocytes, may contribute to immune-mediated control of myeloid leukemias. PMID:25538258

Antibody-mediated delivery of therapeutics for cancer therapy.

PubMed

Parakh, Sagun; Parslow, Adam C; Gan, Hui K; Scott, Andrew M

2016-01-01

Antibody-conjugated therapies (ACTs) combine the specificity of monoclonal antibodies to target cancer cells directly with highly potent payloads, often resulting in superior efficacy and/or reduced toxicity. This represents a new approach to the treatment of cancer. There have been highly promising clinical trial results using this approach with improvements in linker and payload technology. The breadth of current trials examining ACTs in haematological malignancies and solid tumours indicate the potential for clinical impact. This review will provide an overview of ACTs currently in clinical development as well as the principles of antibody delivery and types of payloads used, including cytotoxic drugs, radiolabelled isotopes, nanoparticle-based siRNA particles and immunotoxins. The focus of much of the clinical activity in ACTs has, understandably, been on their use as a monotherapy or in combination with standard of care drugs. This will continue, as will the search for better targets, linkers and payloads. Increasingly, as these drugs enter routine clinical care, important questions will arise regarding how to optimise ACT treatment approaches, including investigation of resistance mechanisms, biomarker and patient selection strategies, understanding of the unique toxicities of these drugs, and combinatorial approaches with standard therapies as well as emerging therapeutic agents like immunotherapy.

Therapeutic Targeting of Siglecs using Antibody- and Glycan-based Approaches

PubMed Central

Angata, Takashi; Nycholat, Corwin M.; Macauley, Matthew S.

2015-01-01

The sialic acid-binding immunoglobulin-like lectins (Siglecs) are a family of immunomodulatory receptors whose functions are regulated by their glycan ligands. Siglecs are attractive therapeutic targets because of their cell-type specific expression pattern, endocytic properties, high expression on certain lymphomas/leukemias, and ability to modulate receptor signaling. Siglec-targeting approaches with therapeutic potential encompass antibody- and glycan-based strategies. Several antibody-based therapies are in clinical trials and continue to be developed for the treatment of lymphoma/leukemia and autoimmune disease, while the therapeutic potential of glycan-based strategies for cargo-delivery and immunomodulation is a promising new approach. Here, we review these strategies with special emphasis on emerging approaches and disease areas that may benefit from targeting the Siglec family. PMID:26435210

Target-Specific Delivery of an Antibody That Blocks the Formation of Collagen Deposits in Skin and Lung.

PubMed

Fertala, Jolanta; Romero, Freddy; Summer, Ross; Fertala, Andrzej

2017-10-01

Regardless of the cause of organ fibrosis, its main unwanted consequence is the formation of collagen fibril-rich deposits that hamper the structure and function of affected tissues. Although many strategies have been proposed for the treatment of fibrotic diseases, no therapy has been developed, which can effectively block the formation of collagen fibril deposits. With this in mind, we recently developed an antibody-based therapy to block key interactions that drive collagen molecules into fibrils. In this study, we analyzed target specificity, which is a main parameter that defines the safe use of all antibody-based therapies in humans. We hypothesized that, regardless of the route of administration, our antibody would preferentially bind to free collagen molecules synthesized at the sites of fibrosis and have minimal off-target interactions when applied in various tissues. To test this hypothesis, we used two experimental models of organ fibrosis: (1) a keloid model, in which antibody constructs were directly implanted under the skin of nude mice and (2) an experimental model of pulmonary fibrosis, in which our antibody was administered systemically by intravenous injection. Following administration, we studied the distribution of our antibody within target and off-target sites as well as analyzed its effects on fibrotic tissue formation. We found that local and systemic application of our antibody had high specificity for targeting collagen fibrillogenesis and also appeared safe and therapeutically effective. In summary, this study provides the basis for further testing our antifibrotic antibody in a broad range of disease conditions and suggests that this treatment approach will be effective if delivered by local or systemic administration.

Maximizing in vivo target clearance by design of pH-dependent target binding antibodies with altered affinity to FcRn.

PubMed

Yang, Danlin; Giragossian, Craig; Castellano, Steven; Lasaro, Marcio; Xiao, Haiguang; Saraf, Himanshu; Hess Kenny, Cynthia; Rybina, Irina; Huang, Zhong-Fu; Ahlberg, Jennifer; Bigwarfe, Tammy; Myzithras, Maria; Waltz, Erica; Roberts, Simon; Kroe-Barrett, Rachel; Singh, Sanjaya

2017-10-01

Antibodies with pH-dependent binding to both target antigens and neonatal Fc receptor (FcRn) provide an alternative tool to conventional neutralizing antibodies, particularly for therapies where reduction in antigen level is challenging due to high target burden. However, the requirements for optimal binding kinetic framework and extent of pH dependence for these antibodies to maximize target clearance from circulation are not well understood. We have identified a series of naturally-occurring high affinity antibodies with pH-dependent target binding properties. By in vivo studies in cynomolgus monkeys, we show that pH-dependent binding to the target alone is not sufficient for effective target removal from circulation, but requires Fc mutations that increase antibody binding to FcRn. Affinity-enhanced pH-dependent FcRn binding that is double-digit nM at pH 7.4 and single-digit nM at pH 6 achieved maximal target reduction when combined with similar target binding affinities in reverse pH directions. Sustained target clearance below the baseline level was achieved 3 weeks after single-dose administration at 1.5 mg/kg. Using the experimentally derived mechanistic model, we demonstrate the essential kinetic interplay between target turnover and antibody pH-dependent binding during the FcRn recycling, and identify the key components for achieving maximal target clearance. These results bridge the demand for improved patient dosing convenience with the "know-how" of therapeutic modality by design.

Antibodies Targeting EMT

DTIC Science & Technology

2015-10-01

of breast cancer does not have specific antibody drugs like Herceptin, and there is considerable need for targeted therapeutics and diagnostic...epithelial to mesenchymal transition” or EMT. This process is important in several cancers , but is particularly associated with “triple-negative” breast ...pathways in cancer cells and make a major impact on breast cancer . 15. SUBJECT TERMS Monoclonal Antibody, Epithelial to Mesenchymal Transition

A novel cancer-targeting transporter with integrin αvβ3 monoclonal antibody functionalized single-walled carbon nanotubes

NASA Astrophysics Data System (ADS)

Ou, Zhongmin; Wu, Baoyan; Xing, Da

2009-08-01

The pursuit of efficient and highly targeting-selective transporters is an active topic in cancer-targeting therapy. In this study, a novel cancer-targeting transporter with integrin αvβ3 monoclonal antibody functionalized single-walled carbon nanotubes (SWCNTs) was developed to investigate cancer cell targeting in vitro. SWCNTs were first modified by phospholipid-bearing polyethylene glycol (PL-PEG). PL-PEG functionalized SWCNTs were then conjugated with fluorescein isothiocyanate (FITC) labeled integrin αvβ3 monoclonal antibody to construct SWCNT-integrin αvβ3 monoclonal antibody system (denoted as SWCNT-PEG-mAb). In vitro study revealed that the system had a high efficiency in cancer cell targeting in integrin αvβ3 positive U87MG cells. Moreover, the SWCNT-PEG-mAb is stable in physiological media, and can be readily transported into U87MG cells via integrin αvβ3-mediated endocytosis in cell. In summary, the integrin αvβ3 monoclonal antibody labeled SWCNT is a potential carrier-candidate for cancer-imaging and drug-delivering in cancer-targeting therapy.

Linker-free conjugation and specific cell targeting of antibody functionalized iron-oxide nanoparticles

PubMed Central

Xu, Yaolin; Baiu, Dana C.; Sherwood, Jennifer A.; McElreath, Meghan R.; Qin, Ying; Lackey, Kimberly H.; Otto, Mario; Bao, Yuping

2015-01-01

Specific targeting is a key step to realize the full potential of iron oxide nanoparticles in biomedical applications, especially tumor-associated diagnosis and therapy. Here, we developed anti-GD2 antibody conjugated iron oxide nanoparticles for highly efficient neuroblastoma cell targeting. The antibody conjugation was achieved through an easy, linker-free method based on catechol reactions. The targeting efficiency and specificity of the antibody-conjugated nanoparticles to GD2-positive neuroblastoma cells were confirmed by flow cytometry, fluorescence microscopy, Prussian blue staining and transmission electron microscopy. These detailed studies indicated that the receptor-recognition capability of the antibody was fully retained after conjugation and the conjugated nanoparticles quickly attached to GD2-positive cells within four hours. Interestingly, longer treatment (12 h) led the cell membrane-bound nanoparticles to be internalized into cytosol, either by directly penetrating the cell membrane or escaping from the endosomes. Last but importantly, the uniquely designed functional surfaces of the nanoparticles allow easy conjugation of other bioactive molecules. PMID:26660881

Molecularly-Targeted Gold-Based Nanoparticles for Cancer Imaging and Near-Infrared Photothermal Therapy

NASA Astrophysics Data System (ADS)

Day, Emily Shannon

2011-12-01

This thesis advances the use of nanoparticles as multifunctional agents for molecularly-targeted cancer imaging and photothermal therapy. Cancer mortality has remained relatively unchanged for several decades, indicating a significant need for improvements in care. Researchers are evaluating strategies incorporating nanoparticles as exogenous energy absorbers to deliver heat capable of inducing cell death selectively to tumors, sparing normal tissue. Molecular targeting of nanoparticles is predicted to improve photothermal therapy by enhancing tumor retention. This hypothesis is evaluated with two types of nanoparticles. The nanoparticles utilized, silica-gold nanoshells and gold-gold sulfide nanoparticles, can convert light energy into heat to damage cancerous cells. For in vivo applications nanoparticles are usually coated with poly(ethylene glycol) (PEG) to increase blood circulation time. Here, heterobifunctional PEG links nanoparticles to targeting agents (antibodies and growth factors) to provide cell-specific binding. This approach is evaluated through a series of experiments. In vitro, antibody-coated nanoparticles can bind breast carcinoma cells expressing the targeted receptor and act as contrast agents for multiphoton microscopy prior to inducing cell death via photoablation. Furthermore, antibody-coated nanoparticles can bind tissue ex vivo at levels corresponding to receptor expression, suggesting they should bind their target even in the complex biological milieu. This is evaluated by comparing the accumulation of antibody-coated and PEG-coated nanoparticles in subcutaneous glioma tumors in mice. Contrary to expectations, antibody targeting did not yield more nanoparticles within tumors. Nevertheless, these studies established the sensitivity of glioma to photothermal therapy; mice treated with PEG-coated nanoshells experienced 57% complete tumor regression versus no regression in control mice. Subsequent experiments employed intracranial tumors to

Structure of solid tumors and their vasculature: Implications for therapy with monoclonal antibodies

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

Dvorak, H.F.; Nagy, J.A.; Dvorak, A.M.

Delivery of monoclonal antibodies to solid tumors is a vexing problem that must be solved if these antibodies are to realize their promise in therapy. Such success as has been achieved with monoclonal antibodies is attributable to the local hyperpermeability of the tumor vasculature, a property that favors antibody extravasation at tumor sites and that is mediated by a tumor-secreted vascular permeability factor. However, leaky tumor blood vessels are generally some distance removed from target tumor cells, separated by stroma and by other tumor cells that together represent significant barriers to penetration by extravasated monoclonal antibodies. For this reason, alternativemore » approaches may be attractive. These include the use of antibody-linked cytotoxins, which are able to kill tumor cells without immediate contact, and direction of antibodies against nontumor cell targets, for example, antigens unique to the tumor vascular endothelium or to tumor stroma. 50 refs.« less

Familial breast cancer - targeted therapy in secondary and tertiary prevention.

PubMed

Kast, Karin; Rhiem, Kerstin

2015-02-01

The introduction of an increasing number of individualized molecular targeted therapies into clinical routine mirrors their importance in modern cancer prevention and treatment. Well-known examples for targeted agents are the monoclonal antibody trastuzumab and the selective estrogen receptor modulator tamoxifen. The identification of an unaltered gene in tumor tissue in colon cancer (KRAS) is a predictor for the patient's response to targeted therapy with a monoclonal antibody (cetuximab). Targeted therapy for hereditary breast and ovarian cancer has become a reality with the approval of olaparib for platin-sensitive late relapsed BRCA-associated ovarian cancer in December 2014. This manuscript reviews the status quo of poly-ADP-ribose polymerase inhibitors (PARPi) in the therapy of breast and ovarian cancer as well as the struggle for carboplatin as a potential standard of care for triple-negative and, in particular, BRCA-associated breast cancer. Details of the mechanism of action with information on tumor development are provided, and an outlook for further relevant research is given. The efficacy of agents against molecular targets together with the identification of an increasing number of cancer-associated genes will open the floodgates to a new era of treatment decision-making based on molecular tumor profiles. Current clinical trials involving patients with BRCA-associated cancer explore the efficacy of the molecular targeted therapeutics platinum and PARPi.

Recombinant immunotoxins and retargeted killer cells: employing engineered antibody fragments for tumor-specific targeting of cytotoxic effectors.

PubMed

Wels, Winfried; Biburger, Markus; Müller, Tina; Dälken, Benjamin; Giesübel, Ulrike; Tonn, Torsten; Uherek, Christoph

2004-03-01

Over the past years, monoclonal antibodies have attracted enormous interest as targeted therapeutics, and a number of such reagents are in clinical use. However, responses could not be achieved in all patients with tumors expressing high levels of the respective target antigens, suggesting that other factors such as limited recruitment of endogenous immune effector mechanisms can also influence treatment outcome. This justifies the search for alternative, potentially more effective reagents. Antibody-toxins and cytolytic effector cells genetically modified to carry antibody-based receptors on the surface, represent such tailor-made targeting vehicles with the potential of improved tumor localization and enhanced efficacy. In this way, advances in recombinant antibody technology have made it possible to circumvent problems inherent in chemical coupling of antibodies and toxins, and have allowed construction via gene fusion of recombinant molecules which combine antibody-mediated recognition of tumor cells with specific delivery of potent protein toxins of bacterial or plant origin. Likewise, recombinant antibody fragments provide the basis for the construction of chimeric antigen receptors that, upon expression in cytotoxic T lymphocytes (CTLs) or natural killer (NK) cells, link antibody-mediated recognition of tumor antigens with these effector cells' potent cytolytic activities, thereby making them promising cellular therapeutics for adoptive cancer therapy. Here, general principles for the derivation of cytotoxic proteins and effector cells with antibody-dependent tumor specificity are summarized, and current strategies to employ these molecules and cells for directed cancer therapy are discussed, focusing mainly on the tumor-associated antigens epidermal growth factor receptor (EGFR) and the closely related ErbB2 (HER2) as targets.

Antibody therapy for Ebola

PubMed Central

Qiu, Xiangguo; Kobinger, Gary P

2014-01-01

Ebola viruses can cause severe hemorrhagic fever in humans and nonhuman primates with fatality rates up to 90%, and are identified as biosafety level 4 pathogens and CDC Category A Agents of Bioterrorism. To date, there are no approved therapies and vaccines available to treat these infections. Antibody therapy was estimated to be an effective and powerful treatment strategy against infectious pathogens in the late 19th, early 20th centuries but has fallen short to meet expectations to widely combat infectious diseases. Passive immunization for Ebola virus was successful in 2012, after over 15 years of failed attempts leading to skepticism that the approach would ever be of potential benefit. Currently, monoclonal antibody (mAbs)-based therapies are the most efficient at reversing the progression of a lethal Ebola virus infection in nonhuman primates, which recapitulate the human disease with the highest similarity. Novel combinations of mAbs can even fully cure lethally infected animals after clinical symptoms and circulating virus have been detected, days into the infection. These new developments have reopened the door for using antibody-based therapies for filovirus infections. Furthermore, they are reigniting hope that these strategies will contribute to better control the spread of other infectious agents and provide new tools against infectious diseases. PMID:24503566

Anti-CD38 antibody therapy: windows of opportunity yielded by the functional characteristics of the target molecule.

PubMed

Chillemi, Antonella; Zaccarello, Gianluca; Quarona, Valeria; Ferracin, Manuela; Ghimenti, Chiara; Massaia, Massimo; Horenstein, Alberto L; Malavasi, Fabio

2013-05-20

In vivo use of monoclonal antibodies (mAbs) has become a mainstay of routine clinical practice in the treatment of various human diseases. A number of molecules can serve as targets, according to the condition being treated. Now entering human clinical trials, CD38 molecule is a particularly attractive target because of its peculiar pattern of expression and its twin role as receptor and ectoenzyme. This review provides a range of analytical perspectives on the current progress in and challenges to anti-CD38 mAb therapy. We present a synopsis of the evidence available on CD38, particularly in myeloma and chronic lymphocytic leukemia (CLL). Our aim is to make the data from basic science helpful and accessible to a diverse clinical audience and, at the same time, to improve its potential for in vivo use. The topics covered include tissue distribution and signal implementation by mAb ligation and the possibility of increasing cell density on target cells by exploiting information about the molecule's regulation in combination with drugs approved for in vivo use. Also analyzed is the behavior of CD38 as an enzyme: CD38 is a component of a pathway leading to the production of adenosine in the tumor microenvironment, thus inducing local anergy. Consequently, not only might CD38 be a prime target for mAb-mediated therapy, but its functional block may contribute to general improvement in cancer immunotherapy and outcomes.

Immune checkpoint inhibitors and targeted therapies for metastatic melanoma: A network meta-analysis.

PubMed

Pasquali, Sandro; Chiarion-Sileni, Vanna; Rossi, Carlo Riccardo; Mocellin, Simone

2017-03-01

Immune checkpoint inhibitors and targeted therapies, two new class of drugs for treatment of metastatic melanoma, have not been compared in randomized controlled trials (RCT). We quantitatively summarized the evidence and compared immune and targeted therapies in terms of both efficacy and toxicity. A comprehensive search for RCTs of immune checkpoint inhibitors and targeted therapies was conducted to August 2016. Using a network meta-analysis approach, treatments were compared with each other and ranked based on their effectiveness (as measured by the impact on progression-free survival [PFS]) and acceptability (the inverse of high grade toxicity). Twelve RCTs enrolling 6207 patients were included. Network meta-analysis generated 15 comparisons. Combined BRAF and MEK inhibitors were associated with longer PFS as compared to anti-CTLA4 (HR: 0.22; 95% confidence interval [CI]: 0.12-0.41) and anti-PD1 antibodies alone (HR: 0.38; CI: 0.20-0.72). However, anti-PD1 monoclonal antibodies were less toxic than anti-CTLA4 monoclonal antibodies (RR: 0.65; CI: 0.40-0.78) and their combination significantly increased toxicity compared to either single agent anti-CTLA4 (RR: 2.06; CI: 1.45-2.93) or anti-PD1 monoclonal antibodies (RR: 3.67; CI: 2.27-5.96). Consistently, ranking analysis suggested that the combination of targeted therapies is the most effective strategy, whereas single agent anti-PD1 antibodies have the best acceptability. The GRADE level of evidence quality for these findings was moderate to low. The simultaneous inhibition of BRAF and MEK appears the most effective treatment for melanomas harboring BRAF V600 mutation, although anti-PD1 antibodies appear to be less toxic. Further research is needed to increase the quality of evidence. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antiviral Activity of HIV gp120 Targeting Bispecific T Cell Engager (BiTE®) Antibody Constructs.

PubMed

Brozy, Johannes; Schlaepfer, Erika; Mueller, Christina K S; Rochat, Mary-Aude; Rampini, Silvana K; Myburgh, Renier; Raum, Tobias; Kufer, Peter; Baeuerle, Patrick A; Muenz, Markus; Speck, Roberto F

2018-05-02

Today's gold standard in HIV therapy is the combined antiretroviral therapy (cART). It requires strict adherence by patients and life-long medication, which can lower the viral load below detection limits and prevent HIV-associated immunodeficiency, but cannot cure patients. The bispecific T cell engaging (BiTE®) antibody technology has demonstrated long-term relapse-free outcomes in patients with relapsed and refractory acute lymphocytic leukemia. We here generated BiTE® antibody constructs that target the HIV-1 envelope protein gp120 (HIV gp120) using either the scFv B12 or VRC01, the first two extracellular domains (1+2) of human CD4 alone or joined to the single chain variable fragment (scFv) of the antibody 17b fused to an anti-human CD3ϵ scFv. These engineered human BiTE® antibody constructs showed engagement of T cells for redirected lysis of HIV gp120-transfected CHO cells. Furthermore, they substantially inhibited HIV-1 replication in PBMCs as well as in macrophages co-cultured with autologous CD8+ T-cells, the most potent being the human CD4(1+2) BiTE® antibody construct and the CD4(1+2)L17b BiTE® antibody construct. The CD4(1+2) h BiTE® antibody construct promoted HIV infection of human CD4-/CD8+ T cells. In contrast, the neutralizing B12 and the VRC01 BiTE® antibody constructs as well as the CD4(1+2)L17b BiTE® antibody construct did not. Thus, BiTE® antibody constructs targeting HIV gp120 are very promising for constraining HIV and warrant further development as novel antiviral therapy with curative potential. Importance HIV is a chronic infection well controlled with the current cART. However, we lack cure of HIV, and the HIV pandemic goes on. Here we showed in vitro and ex vivo t hat a bispecific T-cell engaging (BiTE®) antibody construct targeting HIV gp120 resulted in substantially reduced HIV replication. In addition, these BiTE® antibody constructs display efficient killing of gp120 expressing cells and inhibited replication in ex vivo

Humanized Antibodies for Antiviral Therapy

NASA Astrophysics Data System (ADS)

Co, Man Sung; Deschamps, Marguerite; Whitley, Richard J.; Queen, Cary

1991-04-01

Antibody therapy holds great promise for the treatment of cancer, autoimmune disorders, and viral infections. Murine monoclonal antibodies are relatively easy to produce but are severely restricted for therapeutic use by their immunogenicity in humans. Production of human monoclonal antibodies has been problematic. Humanized antibodies can be generated by introducing the six hypervariable regions from the heavy and light chains of a murine antibody into a human framework sequence and combining it with human constant regions. We humanized, with the aid of computer modeling, two murine monoclonal antibodies against herpes simplex virus gB and gD glycoproteins. The binding, virus neutralization, and cell protection results all indicate that both humanized antibodies have retained the binding activities and the biological properties of the murine monoclonal antibodies.

Targeting of phage particles towards endothelial cells by antibodies selected through a multi-parameter selection strategy.

PubMed

Mandrup, Ole A; Lykkemark, Simon; Kristensen, Peter

2017-02-10

One of the hallmarks of cancer is sustained angiogenesis. Here, normal endothelial cells are activated, and their formation of new blood vessels leads to continued tumour growth. An improved patient condition is often observed when angiogenesis is prevented or normalized through targeting of these genomically stable endothelial cells. However, intracellular targets constitute a challenge in therapy, as the agents modulating these targets have to be delivered and internalized specifically to the endothelial cells. Selection of antibodies binding specifically to certain cell types is well established. It is nonetheless a challenge to ensure that the binding of antibodies to the target cell will mediate internalization. Previously selection of such antibodies has been performed targeting cancer cell lines; most often using either monovalent display or polyvalent display. In this article, we describe selections that isolate internalizing antibodies by sequential combining monovalent and polyvalent display using two types of helper phages, one which increases display valence and one which reduces background. One of the selected antibodies was found to mediate internalization into human endothelial cells, although our results confirms that the single stranded nature of the DNA packaged into phage particles may limit applications aimed at targeting nucleic acids in mammalian cells.

Mucin-based targeted pancreatic cancer therapy.

PubMed

Torres, Maria P; Chakraborty, Subhankar; Souchek, Joshua; Batra, Surinder K

2012-01-01

The prognosis of pancreatic cancer (PC) patients is very poor with a five-year survival of less than 5%. One of the major challenges in developing new therapies for PC is the lack of expression of specific markers by pancreatic tumor cells. Mucins are heavily Oglycosylated proteins characterized by the presence of short stretches of amino acid sequences repeated several times in tandem. The expression of several mucins including MUC1, MUC4, MUC5AC, and MUC16 is strongly upregulated in PC. Recent studies have also demonstrated a link between the aberrant expression and differential overexpression of mucin glycoproteins to the initiation, progression, and poor prognosis of the disease. These studies have led to increasing recognition of mucins as potential diagnostic markers and therapeutic targets in PC. In this focused review we present an overview of the therapies targeting mucins in PC, including immunotherapy (i.e. vaccines, antibodies, and radioimmunoconjugates), gene therapy, and other novel therapeutic strategies.

Broad Detection of Alterations Predicted to Confer Lack of Benefit From EGFR Antibodies or Sensitivity to Targeted Therapy in Advanced Colorectal Cancer.

PubMed

Rankin, Andrew; Klempner, Samuel J; Erlich, Rachel; Sun, James X; Grothey, Axel; Fakih, Marwan; George, Thomas J; Lee, Jeeyun; Ross, Jeffrey S; Stephens, Philip J; Miller, Vincent A; Ali, Siraj M; Schrock, Alexa B

2016-09-28

A KRAS mutation represented the first genomic biomarker to predict lack of benefit from anti-epidermal growth factor receptor (EGFR) antibody therapy in advanced colorectal cancer (CRC). Expanded RAS testing has further refined the treatment approach, but understanding of genomic alterations underlying primary and acquired resistance is limited and further study is needed. We prospectively analyzed 4,422 clinical samples from patients with advanced CRC, using hybrid-capture based comprehensive genomic profiling (CGP) at the request of the individual treating physicians. Comparison with prior molecular testing results, when available, was performed to assess concordance. We identified a RAS/RAF pathway mutation or amplification in 62% of cases, including samples harboring KRAS mutations outside of the codon 12/13 hotspot region in 6.4% of cases. Among cases with KRAS non-codon 12/13 alterations for which prior test results were available, 79 of 90 (88%) were not identified by focused testing. Of 1,644 RAS/RAF wild-type cases analyzed by CGP, 31% harbored a genomic alteration (GA) associated with resistance to anti-EGFR therapy in advanced CRC including mutations in PIK3CA, PTEN, EGFR, and ERBB2. We also identified other targetable GA, including novel kinase fusions, receptor tyrosine kinase amplification, activating point mutations, as well as microsatellite instability. Extended genomic profiling reliably detects alterations associated with lack of benefit to anti-EGFR therapy in advanced CRC, while simultaneously identifying alterations potentially important in guiding treatment. The use of CGP during the course of clinical care allows for the refined selection of appropriate targeted therapies and clinical trials, increasing the chance of clinical benefit and avoiding therapeutic futility. Comprehensive genomic profiling (CGP) detects diverse genomic alterations associated with lack of benefit to anti-epidermal growth factor receptor therapy in advanced

Antibodies directed against receptor tyrosine kinases

PubMed Central

FAUVEL, Bénédicte; Yasri, Aziz

2014-01-01

Approximately 30 therapeutic monoclonal antibodies have already been approved for cancers and inflammatory diseases, and monoclonal antibodies continue to be one of the fastest growing classes of therapeutic molecules. Because aberrant signaling by receptor tyrosine kinases (RTKs) is a commonly observed factor in cancer, most of the subclasses of RTKs are being extensively studied as potential targets for treating malignancies. The first two RTKs that have been targeted by antibody therapy, with five currently marketed antibodies, are the growth factor receptors EGFR and HER2. However, due to systemic side effects, refractory patients and the development of drug resistance, these treatments are being challenged by emerging therapeutics. This review examines current monoclonal antibody therapies against RTKs. After an analysis of agents that have already been approved, we present an analysis of antibodies in clinical development that target RTKs. Finally, we highlight promising RTKs that are emerging as new oncological targets for antibody-based therapy. PMID:24859229

A natural human monoclonal antibody targeting Staphylococcus Protein A protects against Staphylococcus aureus bacteremia

PubMed Central

Varshney, Avanish K.; Sunley, Kevin M.; Bowling, Rodney A.; Kwan, Tzu-Yu; Mays, Heather R.; Rambhadran, Anu; Zhang, Yanfeng; Martin, Rebecca L.; Cavalier, Michael C.; Simard, John

2018-01-01

Staphylococcus aureus can cause devastating and life-threatening infections. With the increase in multidrug resistant strains, novel therapies are needed. Limited success with active and passive immunization strategies have been attributed to S. aureus immune evasion. Here, we report on a monoclonal antibody, 514G3, that circumvents a key S. aureus evasion mechanism by targeting the cell wall moiety Protein A (SpA). SpA tightly binds most subclasses of immunoglobulins via their Fc region, neutralizing effector function. The organism can thus shield itself with a protective coat of serum antibodies and render humoral immunity ineffective. The present antibody reactivity was derived from an individual with natural anti-SpA antibody titers. The monoclonal antibody is of an IgG3 subclass, which differs critically from other immunoglobulin subclasses since its Fc is not bound by SpA. Moreover, it targets a unique epitope on SpA that allows it to bind in the presence of serum antibodies. Consequently, the antibody opsonizes S. aureus and maintains effector function to enable natural immune mediated clearance. The data presented here provide evidence that 514G3 antibody is able to successfully rescue mice from S. aureus mediated bacteremia. PMID:29364906

Design of antibody-functionalized carbon nanotubes filled with radioactivable metals towards a targeted anticancer therapy

NASA Astrophysics Data System (ADS)

Spinato, Cinzia; Perez Ruiz de Garibay, Aritz; Kierkowicz, Magdalena; Pach, Elzbieta; Martincic, Markus; Klippstein, Rebecca; Bourgognon, Maxime; Wang, Julie Tzu-Wen; Ménard-Moyon, Cécilia; Al-Jamal, Khuloud T.; Ballesteros, Belén; Tobias, Gerard; Bianco, Alberto

2016-06-01

In the present work we have devised the synthesis of a novel promising carbon nanotube carrier for the targeted delivery of radioactivity, through a combination of endohedral and exohedral functionalization. Steam-purified single-walled carbon nanotubes (SWCNTs) have been initially filled with radioactive analogues (i.e. metal halides) and sealed by high temperature treatment, affording closed-ended CNTs with the filling material confined in the inner cavity. The external functionalization of these filled CNTs was then achieved by nitrene cycloaddition and followed by the derivatization with a monoclonal antibody (Cetuximab) targeting the epidermal growth factor receptor (EGFR), overexpressed by several cancer cells. The targeting efficiency of the so-obtained conjugate was evaluated by immunostaining with a secondary antibody and by incubation of the CNTs with EGFR positive cells (U87-EGFR+), followed by flow cytometry, confocal microscopy or elemental analyses. We demonstrated that our filled and functionalized CNTs can internalize more efficiently in EGFR positive cancer cells.In the present work we have devised the synthesis of a novel promising carbon nanotube carrier for the targeted delivery of radioactivity, through a combination of endohedral and exohedral functionalization. Steam-purified single-walled carbon nanotubes (SWCNTs) have been initially filled with radioactive analogues (i.e. metal halides) and sealed by high temperature treatment, affording closed-ended CNTs with the filling material confined in the inner cavity. The external functionalization of these filled CNTs was then achieved by nitrene cycloaddition and followed by the derivatization with a monoclonal antibody (Cetuximab) targeting the epidermal growth factor receptor (EGFR), overexpressed by several cancer cells. The targeting efficiency of the so-obtained conjugate was evaluated by immunostaining with a secondary antibody and by incubation of the CNTs with EGFR positive cells (U87

Antibody-mediated targeting of replication-competent retroviral vectors.

PubMed

Tai, Chien-Kuo; Logg, Christopher R; Park, Jinha M; Anderson, W French; Press, Michael F; Kasahara, Noriyuki

2003-05-20

Replication-competent murine leukemia virus (MLV) vectors can be engineered to achieve high efficiency gene transfer to solid tumors in vivo and tumor-restricted replication, however their safety can be further enhanced by redirecting tropism of the virus envelope. We have therefore tested the targeting capability and replicative stability of ecotropic and amphotropic replication-competent retrovirus (RCR) vectors containing two tandem repeats from the immunoglobulin G-binding domain of Staphylococcal protein A inserted into the proline-rich "hinge" region of the envelope, which enables modular use of antibodies of various specificities for vector targeting. The modified envelopes were efficiently expressed and incorporated into virions, were capable of capturing monoclonal anti-HER2 antibodies, and mediated efficient binding of the virus-antibody complex to HER2-positive target cells. While infectivity was markedly reduced by pseudotyping with targeted envelopes alone, coexpression of wild-type envelope rescued efficient cellular entry. Both ecotropic and amphotropic RCR vector/anti-HER2 antibody complexes achieved significant enhancement of transduction on murine target cells overexpressing HER2, which could be competed by preincubation with excess free antibodies. Interestingly, HER2-expressing human breast cancer cells did not show enhancement of transduction despite efficient antibody-mediated cell surface binding, suggesting that target cell-specific parameters markedly affect the efficiency of post-binding entry processes. Serial replication of targeted vectors resulted in selection of Z domain deletion variants, but reduction of the overall size of the vector genome enhanced its stability. Application of antibody-mediated targeting to the initial localization of replication-competent virus vectors to tumor sites will thus require optimized target selection and vector design.

One target, different effects: a comparison of distinct therapeutic antibodies against the same targets.

PubMed

Shim, Hyunbo

2011-10-31

To date, more than 30 antibodies have been approved worldwide for therapeutic use. While the monoclonal antibody market is rapidly growing, the clinical use of therapeutic antibodies is mostly limited to treatment of cancers and immunological disorders. Moreover, antibodies against only five targets (TNF-α, HER2, CD20, EGFR, and VEGF) account for more than 80 percent of the worldwide market of therapeutic antibodies. The shortage of novel, clinically proven targets has resulted in the development of many distinct therapeutic antibodies against a small number of proven targets, based on the premise that different antibody molecules against the same target antigen have distinct biological and clinical effects from one another. For example, four antibodies against TNF-α have been approved by the FDA -- infliximab, adalimumab, golimumab, and certolizumab pegol -- with many more in clinical and preclinical development. The situation is similar for HER2, CD20, EGFR, and VEGF, each having one or more approved antibodies and many more under development. This review discusses the different binding characteristics, mechanisms of action, and biological and clinical activities of multiple monoclonal antibodies against TNF-α, HER-2, CD20, and EGFR and provides insights into the development of therapeutic antibodies.

CD22 antigen is broadly expressed on lung cancer cells and is a target for antibody-based therapy.

PubMed

Tuscano, Joseph M; Kato, Jason; Pearson, David; Xiong, Chengyi; Newell, Laura; Ma, Yunpeng; Gandara, David R; O'Donnell, Robert T

2012-11-01

Most patients with lung cancer still die from their disease, necessitating additional options to improve treatment. Here, we provide evidence for targeting CD22, a cell adhesion protein known to influence B-cell survival that we found is also widely expressed in lung cancer cells. In characterizing the antitumor activity of an established anti-CD22 monoclonal antibody (mAb), HB22.7, we showed CD22 expression by multiple approaches in various lung cancer subtypes, including 7 of 8 cell lines and a panel of primary patient specimens. HB22.7 displayed in vitro and in vivo cytotoxicity against CD22-positive human lung cancer cells and tumor xenografts. In a model of metastatic lung cancer, HB22.7 inhibited the development of pulmonary metastasis and extended overall survival. The finding that CD22 is expressed on lung cancer cells is significant in revealing a heretofore unknown mechanism of tumorigenesis and metastasis. Our work suggests that anti-CD22 mAbs may be useful for targeted therapy of lung cancer, a malignancy that has few tumor-specific targets. ©2012 AACR.

Function-blocking antibodies to human vascular adhesion protein-1: a potential anti-inflammatory therapy.

PubMed

Kirton, Christopher M; Laukkanen, Marja-Leena; Nieminen, Antti; Merinen, Marika; Stolen, Craig M; Armour, Kathryn; Smith, David J; Salmi, Marko; Jalkanen, Sirpa; Clark, Michael R

2005-11-01

Human vascular adhesion protein-1 (VAP-1) is a homodimeric 170-kDa sialoglycoprotein that is expressed on the surface of endothelial cells and functions as a semicarbazide-sensitive amine oxidase and as an adhesion molecule. Blockade of VAP-1 has been shown to reduce leukocyte adhesion and transmigration in in vivo and in vitro models, suggesting that VAP-1 is a potential target for anti-inflammatory therapy. In this study we have constructed mouse-human chimeric antibodies by genetic engineering in order to circumvent the potential problems involved in using murine antibodies in man. Our chimeric anti-VAP-1 antibodies, which were designed to lack Fc-dependent effector functions, bound specifically to cell surface-expressed recombinant human VAP-1 and recognized VAP-1 in different cell types in tonsil. Furthermore, the chimeric antibodies prevented leukocyte adhesion and transmigration in vitro and in vivo. Hence, these chimeric antibodies have the potential to be used as a new anti-inflammatory therapy.

Rebmab200, a humanized monoclonal antibody targeting the sodium phosphate transporter NaPi2b displays strong immune mediated cytotoxicity against cancer: a novel reagent for targeted antibody therapy of cancer.

PubMed

Lopes dos Santos, Mariana; Yeda, Fernanda Perez; Tsuruta, Lilian Rumi; Horta, Bruno Brasil; Pimenta, Alécio A; Degaki, Theri Leica; Soares, Ibere C; Tuma, Maria Carolina; Okamoto, Oswaldo Keith; Alves, Venancio A F; Old, Lloyd J; Ritter, Gerd; Moro, Ana Maria

2013-01-01

NaPi2b, a sodium-dependent phosphate transporter, is highly expressed in ovarian carcinomas and is recognized by the murine monoclonal antibody MX35. The antibody had shown excellent targeting to ovarian cancer in several early phase clinical trials but being murine the antibody's full therapeutic potential could not be explored. To overcome this impediment we developed a humanized antibody version named Rebmab200, expressed in human PER.C6® cells and cloned by limiting dilution. In order to select a clone with high therapeutic potential clones were characterized using a series of physicochemical assays, flow cytometry, real-time surface plasmon resonance, glycosylation analyses, immunohistochemistry, antibody-dependent cell-mediated cytotoxicity, complement-dependent-cytotoxicity assays and quantitative PCR. Comparative analyses of Rebmab200 and MX35 monoclonal antibodies demonstrated that the two antibodies had similar specificity for NaPi2b by flow cytometry with a panel of 30 cell lines and maintained similar kinetic parameters. Robust and high producer cell clones potentially suitable for use in manufacturing were obtained. Rebmab200 antibodies were assessed by immunohistochemistry using a large panel of tissues including human carcinomas of ovarian, lung, kidney and breast origin. An assessment of its binding towards 33 normal human organs was performed as well. Rebmab200 showed selected strong reactivity with the tested tumor types but little or no reactivity with the normal tissues tested confirming its potential for targeted therapeutics strategies. The remarkable cytotoxicity shown by Rebmab200 in OVCAR-3 cells is a significant addition to the traits of stability and productivity displayed by the top clones of Rebmab200. Antibody-dependent cell-mediated toxicity functionality was confirmed in repeated assays using cancer cell lines derived from ovary, kidney and lung as targets. To explore use of this antibody in clinical trials, GMP production of Rebmab

Rebmab200, a Humanized Monoclonal Antibody Targeting the Sodium Phosphate Transporter NaPi2b Displays Strong Immune Mediated Cytotoxicity against Cancer: A Novel Reagent for Targeted Antibody Therapy of Cancer

PubMed Central

dos Santos, Mariana Lopes; Yeda, Fernanda Perez; Tsuruta, Lilian Rumi; Horta, Bruno Brasil; Pimenta, Alécio A.; Degaki, Theri Leica; Soares, Ibere C.; Tuma, Maria Carolina; Okamoto, Oswaldo Keith; Alves, Venancio A. F.; Ritter, Gerd; Moro, Ana Maria

2013-01-01

NaPi2b, a sodium-dependent phosphate transporter, is highly expressed in ovarian carcinomas and is recognized by the murine monoclonal antibody MX35. The antibody had shown excellent targeting to ovarian cancer in several early phase clinical trials but being murine the antibody's full therapeutic potential could not be explored. To overcome this impediment we developed a humanized antibody version named Rebmab200, expressed in human PER.C6® cells and cloned by limiting dilution. In order to select a clone with high therapeutic potential clones were characterized using a series of physicochemical assays, flow cytometry, real-time surface plasmon resonance, glycosylation analyses, immunohistochemistry, antibody-dependent cell-mediated cytotoxicity, complement-dependent-cytotoxicity assays and quantitative PCR. Comparative analyses of Rebmab200 and MX35 monoclonal antibodies demonstrated that the two antibodies had similar specificity for NaPi2b by flow cytometry with a panel of 30 cell lines and maintained similar kinetic parameters. Robust and high producer cell clones potentially suitable for use in manufacturing were obtained. Rebmab200 antibodies were assessed by immunohistochemistry using a large panel of tissues including human carcinomas of ovarian, lung, kidney and breast origin. An assessment of its binding towards 33 normal human organs was performed as well. Rebmab200 showed selected strong reactivity with the tested tumor types but little or no reactivity with the normal tissues tested confirming its potential for targeted therapeutics strategies. The remarkable cytotoxicity shown by Rebmab200 in OVCAR-3 cells is a significant addition to the traits of stability and productivity displayed by the top clones of Rebmab200. Antibody-dependent cell-mediated toxicity functionality was confirmed in repeated assays using cancer cell lines derived from ovary, kidney and lung as targets. To explore use of this antibody in clinical trials, GMP production of Rebmab

Antibody-drug conjugate targeting CD46 eliminates multiple myeloma cells.

PubMed

Sherbenou, Daniel W; Aftab, Blake T; Su, Yang; Behrens, Christopher R; Wiita, Arun; Logan, Aaron C; Acosta-Alvear, Diego; Hann, Byron C; Walter, Peter; Shuman, Marc A; Wu, Xiaobo; Atkinson, John P; Wolf, Jeffrey L; Martin, Thomas G; Liu, Bin

2016-12-01

Multiple myeloma is incurable by standard approaches because of inevitable relapse and development of treatment resistance in all patients. In our prior work, we identified a panel of macropinocytosing human monoclonal antibodies against CD46, a negative regulator of the innate immune system, and constructed antibody-drug conjugates (ADCs). In this report, we show that an anti-CD46 ADC (CD46-ADC) potently inhibited proliferation in myeloma cell lines with little effect on normal cells. CD46-ADC also potently eliminated myeloma growth in orthometastatic xenograft models. In primary myeloma cells derived from bone marrow aspirates, CD46-ADC induced apoptosis and cell death, but did not affect the viability of nontumor mononuclear cells. It is of clinical interest that the CD46 gene resides on chromosome 1q, which undergoes genomic amplification in the majority of relapsed myeloma patients. We found that the cell surface expression level of CD46 was markedly higher in patient myeloma cells with 1q gain than in those with normal 1q copy number. Thus, genomic amplification of CD46 may serve as a surrogate for target amplification that could allow patient stratification for tailored CD46-targeted therapy. Overall, these findings indicate that CD46 is a promising target for antibody-based treatment of multiple myeloma, especially in patients with gain of chromosome 1q.

Advances of Molecular Targeted Therapy in Gastric Cancer.

PubMed

Cetin, Bulent; Gumusay, Ozge; Cengiz, Mustafa; Ozet, Ahmet

2016-06-01

Gastric cancer is the second most common cause of cancer-related death in the world, and its prognosis remains poor with a median overall survival of 12 months for advanced disease. Advances in the understanding of molecular genetics have led to the development of directed molecular targeted therapy in gastric cancer, leading to improve patient outcomes and quality of life. In the treatment of human epidermal growth factor receptor 2 (HER2)-positive gastric cancer, the addition of trastuzumab significantly improves survival in the first-line setting of therapy. Ramucirumab, an antibody directed against vascular endothelial growth factor receptor 2, significantly improved progression-free and overall survival and has been approved for second-line treatment of gastric cancer. Anti-mesenchymal-epithelial transition (c-MET), mammalian target of rapamycin inhibitors, and polo-like kinase 1 inhibitors are under investigation as a novel therapeutic option for the treatment of gastric cancer. The novel therapies target the key immune checkpoint interaction between a T cell co-inhibitory receptor called programmed death 1 (PD-1) and one of its immunosuppressive ligands, PD-L1. This article reviews molecular targeted therapies in gastric cancer, in light of recent advances.

Targeted anti-IL-13 therapies in asthma: current data and future perspectives.

PubMed

Ntontsi, Polyxeni; Papathanassiou, Evgenia; Loukides, Stelios; Bakakos, Petros; Hillas, Georgios

2018-02-01

The identification of patients with severe asthma who will benefit from a personalized management approach remains an unmet need. Interleukin-13 (IL-13) is a cytokine possessing a significant role in asthma pathogenesis and progression of disease. Humanised monoclonal antibodies against IL-13 and IL-13 and IL-4 receptors are mainly proposed as add-on therapy in patients with T H 2-high inflammation with uncontrolled asthma despite maximum therapy. Areas covered: The role of IL-13 in airway inflammation in severe asthma, the targeted anti-IL-13 therapies and biomarkers that predict response to anti-IL-13 treatment are discussed. Expert opinion: New effective individualized therapies in severe asthma are urgently needed to block specific inflammatory pathways using monoclonal antibodies. Studies on anti-IL-13 therapies showed that asthmatic patients could benefit from this novel targeted therapy as far as lung function and exacerbation rate are concerned. T H 2-high and especially periostin-high groups of asthmatics with moderate-to-severe uncontrolled asthma seem to compose the group that could benefit from anti-IL-13 therapy. Targeting IL-13 alone may not be sufficient to achieve asthma control. Inhibition of IL-13 and IL-4 with mabs may be more encouraging and patients will probably have additional benefits from these therapeutic interventions because of IL-13/IL-4 overlapping actions in asthma pathophysiology.

A bi-functional antibody-receptor domain fusion protein simultaneously targeting IGF-IR and VEGF for degradation

PubMed Central

Shen, Yang; Zeng, Lin; Novosyadlyy, Ruslan; Forest, Amelie; Zhu, Aiping; Korytko, Andrew; Zhang, Haifan; Eastman, Scott W; Topper, Michael; Hindi, Sagit; Covino, Nicole; Persaud, Kris; Kang, Yun; Burtrum, Douglas; Surguladze, David; Prewett, Marie; Chintharlapalli, Sudhakar; Wroblewski, Victor J; Shen, Juqun; Balderes, Paul; Zhu, Zhenping; Snavely, Marshall; Ludwig, Dale L

2015-01-01

Bi-specific antibodies (BsAbs), which can simultaneously block 2 tumor targets, have emerged as promising therapeutic alternatives to combinations of individual monoclonal antibodies. Here, we describe the engineering and development of a novel, human bi-functional antibody-receptor domain fusion molecule with ligand capture (bi-AbCap) through the fusion of the domain 2 of human vascular endothelial growth factor receptor 1 (VEGFR1) to an antibody directed against insulin-like growth factor – type I receptor (IGF-IR). The bi-AbCap possesses excellent stability and developability, and is the result of minimal engineering. Beyond potent neutralizing activities against IGF-IR and VEGF, the bi-AbCap is capable of cross-linking VEGF to IGF-IR, leading to co-internalization and degradation of both targets by tumor cells. In multiple mouse xenograft tumor models, the bi-AbCap improves anti-tumor activity over individual monotherapies. More importantly, it exhibits superior inhibition of tumor growth, compared with the combination of anti-IGF-IR and anti-VEGF therapies, via powerful blockade of both direct tumor cell growth and tumor angiogenesis. The unique “capture-for-degradation” mechanism of the bi-AbCap is informative for the design of next-generation bi-functional anti-cancer therapies directed against independent signaling pathways. The bi-AbCap design represents an alternative approach to the creation of dual-targeting antibody fusion molecules by taking advantage of natural receptor-ligand interactions. PMID:26073904

Targeting the MET oncogene by concomitant inhibition of receptor and ligand via an antibody-"decoy" strategy.

PubMed

Basilico, Cristina; Modica, Chiara; Maione, Federica; Vigna, Elisa; Comoglio, Paolo M

2018-04-25

MET, a master gene sustaining "invasive growth," is a relevant target for cancer precision therapy. In the vast majority of tumors, wild-type MET behaves as a "stress-response" gene and relies on the ligand (HGF) to sustain cell "scattering," invasive growth and apoptosis protection (oncogene "expedience"). In this context, concomitant targeting of MET and HGF could be crucial to reach effective inhibition. To test this hypothesis, we combined an anti-MET antibody (MvDN30) inducing "shedding" (i.e., removal of MET from the cell surface), with a "decoy" (i.e., the soluble extracellular domain of the MET receptor) endowed with HGF-sequestering ability. To avoid antibody/decoy interaction-and subsequent neutralization-we identified a single aminoacid in the extracellular domain of MET-lysine 842-that is critical for MvDN30 binding and engineered the corresponding recombinant decoyMET (K842E). DecoyMET K842E retains the ability to bind HGF with high affinity and inhibits HGF-induced MET phosphorylation. In HGF-dependent cellular models, MvDN30 antibody and decoyMET K842E used in combination cooperate in restraining invasive growth, and synergize in blocking cancer cell "scattering." The antibody and the decoy unbridle apoptosis of colon cancer stem cells grown in vitro as spheroids. In a preclinical model, built by orthotopic transplantation of a human pancreatic carcinoma in SCID mice engineered to express human HGF, concomitant treatment with antibody and decoy significantly reduces metastatic spread. The data reported indicate that vertical targeting of the MET/HGF axis results in powerful inhibition of ligand-dependent MET activation, providing proof of concept in favor of combined target therapy of MET "expedience." © 2018 UICC.

Antibody-cytokine fusion proteins for improving efficacy and safety of cancer therapy.

PubMed

Valedkarimi, Zahra; Nasiri, Hadi; Aghebati-Maleki, Leili; Majidi, Jafar

2017-11-01

Cytokines are key players in the regulation of immune responses both in physiological and pathological states. A number of cytokines have been evaluated in clinical trials and shown promising results in the treatment of different malignancies. Despite this, the clinical application of these molecules may be plagued by undesirable side effects The development of recombinant antibody-cytokine fusion proteins, which offer a means for target delivery of cytokines toward the tumor site, has significantly improved the therapeutic index of these immunomodulatory molecules. Selective tumor localization is provided by the monoclonal antibody component of the fusion protein that binds to the molecules present on the surface of tumor cells or accumulated preferentially in the diseased site. In this manner, the cytokine element is specifically located at the tumor site and can stimulate immune cells with appropriate cytokine receptors. Over the recent years, several antibody-cytokine fusion proteins have been developed with the capacity to target a wide variety of cancers whose application, in some cases, has led to complete rejection of the tumor. These findings support the notion that antibody-cytokine fusion proteins represent huge potential for cancer therapy. This review presents an overview of the advances made in the field of targeted cytokine delivery, which is made possible by genetically engineering antibody-cytokine fusion proteins. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Targeted and Nontargeted α-Particle Therapies.

PubMed

McDevitt, Michael R; Sgouros, George; Sofou, Stavroula

2018-06-04

α-Particle irradiation of cancerous tissue is increasingly recognized as a potent therapeutic option. We briefly review the physics, radiobiology, and dosimetry of α-particle emitters, as well as the distinguishing features that make them unique for radiopharmaceutical therapy. We also review the emerging clinical role of α-particle therapy in managing cancer and recent studies on in vitro and preclinical α-particle therapy delivered by antibodies, other small molecules, and nanometer-sized particles. In addition to their unique radiopharmaceutical characteristics, the increased availability and improved radiochemistry of α-particle radionuclides have contributed to the growing recent interest in α-particle radiotherapy. Targeted therapy strategies have presented novel possibilities for the use of α-particles in the treatment of cancer. Clinical experience has already demonstrated the safe and effective use of α-particle emitters as potent tumor-selective drugs for the treatment of leukemia and metastatic disease.

Targeted and Nontargeted α-Particle Therapies

PubMed Central

McDevitt, Michael R.; Sgouros, George; Sofou, Stavroula

2018-01-01

α-Particle irradiation of cancerous tissue is increasingly recognized as a potent therapeutic option. We briefly review the physics, radiobiology, and dosimetry of α-particle emitters, as well as the distinguishing features that make them unique for radiopharmaceutical therapy. We also review the emerging clinical role of α-particle therapy in managing cancer and recent studies on in vitro and preclinical α-particle therapy delivered by antibodies, other small molecules, and nanometer-sized particles. In addition to their unique radiopharmaceutical characteristics, the increased availability and improved radiochemistry of α-particle radionuclides have contributed to the growing recent interest in α-particle radiotherapy. Targeted therapy strategies have presented novel possibilities for the use of α-particles in the treatment of cancer. Clinical experience has already demonstrated the safe and effective use of α-particle emitters as potent tumor-selective drugs for the treatment of leukemia and metastatic disease. PMID:29345977

IBC’s 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics International Conferences and the 2012 Annual Meeting of The Antibody Society

PubMed Central

Klöhn, Peter-Christian; Wuellner, Ulrich; Zizlsperger, Nora; Zhou, Yu; Tavares, Daniel; Berger, Sven; Zettlitz, Kirstin A.; Proetzel, Gabriele; Yong, May; Begent, Richard H.J.; Reichert, Janice M

2013-01-01

The 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics international conferences, and the 2012 Annual Meeting of The Antibody Society, organized by IBC Life Sciences with contributions from The Antibody Society and two Scientific Advisory Boards, were held December 3–6, 2012 in San Diego, CA. The meeting drew over 800 participants who attended sessions on a wide variety of topics relevant to antibody research and development. As a prelude to the main events, a pre-conference workshop held on December 2, 2012 focused on intellectual property issues that impact antibody engineering. The Antibody Engineering Conference was composed of six sessions held December 3–5, 2012: (1) From Receptor Biology to Therapy; (2) Antibodies in a Complex Environment; (3) Antibody Targeted CNS Therapy: Beyond the Blood Brain Barrier; (4) Deep Sequencing in B Cell Biology and Antibody Libraries; (5) Systems Medicine in the Development of Antibody Therapies/Systematic Validation of Novel Antibody Targets; and (6) Antibody Activity and Animal Models. The Antibody Therapeutics conference comprised four sessions held December 4–5, 2012: (1) Clinical and Preclinical Updates of Antibody-Drug Conjugates; (2) Multifunctional Antibodies and Antibody Combinations: Clinical Focus; (3) Development Status of Immunomodulatory Therapeutic Antibodies; and (4) Modulating the Half-Life of Antibody Therapeutics. The Antibody Society’s special session on applications for recording and sharing data based on GIATE was held on December 5, 2012, and the conferences concluded with two combined sessions on December 5–6, 2012: (1) Development Status of Early Stage Therapeutic Antibodies; and (2) Immunomodulatory Antibodies for Cancer Therapy. PMID:23575266

Efficacy of anti-RON antibody Zt/g4-drug maytansinoid conjugation (Anti-RON ADC) as a novel therapeutics for targeted colorectal cancer therapy.

PubMed

Feng, Liang; Yao, Hang-Ping; Wang, Wei; Zhou, Yong-Qing; Zhou, Jianwei; Zhang, Ruiwen; Wang, Ming-Hai

2014-12-01

The receptor tyrosine kinase RON is critical in epithelial tumorigenesis and a drug target for cancer therapy. Here, we report the development and therapeutic efficacy of a novel anti-RON antibody Zt/g4-maytansinoid (DM1) conjugates for targeted colorectal cancer (CRC) therapy. Zt/g4 (IgG1a/κ) was conjugated to DM1 via thioether linkage to form Zt/g4-DM1 with a drug-antibody ratio of 4:1. CRC cell lines expressing different levels of RON were tested in vitro to determine Zt/g4-DM1-induced RON endocytosis, cell-cycle arrest, and cytotoxicity. Efficacy of Zt/g4-DM1 in vivo was evaluated in mouse xenograft CRC tumor model. Zt/g4-DM1 rapidly induced RON endocytosis, arrested cell cycle at G2-M phase, reduced cell viability, and caused massive cell death within 72 hours. In mouse xenograft CRC models, Zt/g4-DM1 at a single dose of 20 mg/kg body weight effectively delayed CRC cell-mediated tumor growth up to 20 days. In a multiple dose-ranging study with a five injection regimen, Zt/g4-DM1 inhibited more than 90% tumor growth at doses of 7, 10, and 15 mg/kg body weight. The minimal dose achieving 50% of tumor inhibition was approximately 5.0 mg/kg. The prepared Zt/g4-DM1 is stable at 37°C for up to 30 days. At 60 mg/kg, Zt/g4-DM1 had a moderate toxicity in vivo with an average of 12% reduction in mouse body weight. Zt/g4-DM1 is highly effective in targeted inhibition of CRC cell-derived tumor growth in mouse xenograft models. This work provides the basis for development of humanized Zt/g4-DM1 for RON-targeted CRC therapy in the future. ©2014 American Association for Cancer Research.

Targeted therapy with MXD3 siRNA, anti-CD22 antibody and nanoparticles for precursor B-cell acute lymphoblastic leukaemia.

PubMed

Satake, Noriko; Duong, Connie; Chen, Cathy; Barisone, Gustavo A; Diaz, Elva; Tuscano, Joseph; Rocke, David M; Nolta, Jan; Nitin, Nitin

2014-11-01

Conventional chemotherapy for precursor B-cell (preB) acute lymphoblastic leukaemia (ALL) has limitations that could be overcome by targeted therapy. Previously, we discovered a potential therapeutic molecular target, MDX3 (MAX dimerization protein 3), in preB ALL. In this study, we hypothesize that an effective siRNA therapy for preB ALL can be developed using antiCD22 antibody (αCD22 Ab) and nanoparticles. We composed nanocomplexes with super paramagnetic iron oxide nanoparticles (SPIO NPs), αCD22 Abs and MXD3 siRNA molecules based on physical interactions between the molecules. We demonstrated that the MXD3 siRNA-αCD22 Ab-SPIO NP complexes entered leukaemia cells and knocked down MXD3, leading the cells to undergo apoptosis and resulting in decreased live cell counts in the cell line Reh and in primary preB ALL samples in vitro. Furthermore, the cytotoxic effects of the MXD3 siRNA-αCD22 Ab-SPIO NP complexes were significantly enhanced by addition of the chemotherapy drugs vincristine or doxorubicin. We also ruled out potential cytotoxic effects of the MXD3 siRNA-αCD22 Ab-SPIO NP complexes on normal primary haematopoietic cells. Normal B cells were affected while CD34-positive haematopoietic stem cells and non-B cells were not. These data suggest that MXD3 siRNA-αCD22 Ab-SPIO NP complexes have the potential to be a new targeted therapy for preB ALL. © 2014 John Wiley & Sons Ltd.

Development of cell-penetrating bispecific antibodies targeting the N-terminal domain of androgen receptor for prostate cancer therapy.

PubMed

Goicochea, Nancy L; Garnovskaya, Maria; Blanton, Mary G; Chan, Grace; Weisbart, Richard; Lilly, Michael B

2017-12-01

Castration-resistant prostate cancer cells exhibit continued androgen receptor signaling in spite of low levels of ligand. Current therapies to block androgen receptor signaling act by inhibiting ligand production or binding. We developed bispecific antibodies capable of penetrating cells and binding androgen receptor outside of the ligand-binding domain. Half of the bispecific antibody molecule consists of a single-chain variable fragment of 3E10, an anti-DNA antibody that enters cells. The other half is a single-chain variable fragment version of AR441, an anti-AR antibody. The resulting 3E10-AR441 bispecific antibody enters human LNCaP prostate cells and accumulates in the nucleus. The antibody binds to wild-type, mutant and splice variant androgen receptor. Binding affinity of 3E10-AR441 to androgen receptor (284 nM) was lower than that of the parental AR441 mAb (4.6 nM), but could be improved (45 nM) through alternative placement of the affinity tags, and ordering of the VH and VK domains. The 3E10-AR441 bispecific antibody blocked genomic signaling by wild-type or splice variant androgen receptor in LNCaP cells. It also blocked non-genomic signaling by the wild-type receptor. Furthermore, bispecific antibody inhibited the growth of C4-2 prostate cancer cells under androgen-stimulated conditions. The 3E10-AR441 biAb can enter prostate cancer cells and inhibits androgen receptor function in a ligand-independent manner. It may be an attractive prototype agent for prostate cancer therapy. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Enzymatic single-chain antibody tagging: a universal approach to targeted molecular imaging and cell homing in cardiovascular disease.

PubMed

Ta, H T; Prabhu, S; Leitner, E; Jia, F; von Elverfeldt, D; Jackson, Katherine E; Heidt, T; Nair, A K N; Pearce, H; von Zur Muhlen, C; Wang, X; Peter, K; Hagemeyer, C E

2011-08-05

Antibody-targeted delivery of imaging agents can enhance the sensitivity and accuracy of current imaging techniques. Similarly, homing of effector cells to disease sites increases the efficacy of regenerative cell therapy while reducing the number of cells required. Currently, targeting can be achieved via chemical conjugation to specific antibodies, which typically results in the loss of antibody functionality and in severe cell damage. An ideal conjugation technique should ensure retention of antigen-binding activity and functionality of the targeted biological component. To develop a biochemically robust, highly reproducible, and site-specific coupling method using the Staphylococcus aureus sortase A enzyme for the conjugation of a single-chain antibody (scFv) to nanoparticles and cells for molecular imaging and cell homing in cardiovascular diseases. This scFv specifically binds to activated platelets, which play a pivotal role in thrombosis, atherosclerosis, and inflammation. The conjugation procedure involves chemical and enzyme-mediated coupling steps. The scFv was successfully conjugated to iron oxide particles (contrast agents for magnetic resonance imaging) and to model cells. Conjugation efficiency ranged between 50% and 70%, and bioactivity of the scFv after coupling was preserved. The targeting of scFv-coupled cells and nanoparticles to activated platelets was strong and specific as demonstrated in in vitro static adhesion assays, in a flow chamber system, in mouse intravital microscopy, and in in vivo magnetic resonance imaging of mouse carotid arteries. This unique biotechnological approach provides a versatile and broadly applicable tool for procuring targeted regenerative cell therapy and targeted molecular imaging in cardiovascular and inflammatory diseases and beyond.

Addressing the Immunogenicity of the Cargo and of the Targeting Antibodies with a Focus on Deimmunized Bacterial Toxins and on Antibody-Targeted Human Effector Proteins

PubMed Central

Grinberg, Yehudit; Benhar, Itai

2017-01-01

Third-generation immunotoxins are composed of a human, or humanized, targeting moiety, usually a monoclonal antibody or an antibody fragment, and a non-human effector molecule. Due to the non-human origin of the cytotoxic domain, these molecules stimulate potent anti-drug immune responses, which limit treatment options. Efforts are made to deimmunize such immunotoxins or to combine treatment with immunosuppression. An alternative approach is using the so-called “human cytotoxic fusion proteins”, in which antibodies are used to target human effector proteins. Here, we present three relevant approaches for reducing the immunogenicity of antibody-targeted protein therapeutics: (1) reducing the immunogenicity of the bacterial toxin, (2) fusing human cytokines to antibodies to generate immunocytokines and (3) addressing the immunogenicity of the targeting antibodies. PMID:28574434

A collagen-binding EGFR antibody fragment targeting tumors with a collagen-rich extracellular matrix.

PubMed

Liang, Hui; Li, Xiaoran; Wang, Bin; Chen, Bing; Zhao, Yannan; Sun, Jie; Zhuang, Yan; Shi, Jiajia; Shen, He; Zhang, Zhijun; Dai, Jianwu

2016-02-17

Many tumors over-express collagen, which constitutes the physical scaffold of tumor microenvironment. Collagen has been considered to be a target for cancer therapy. The collagen-binding domain (CBD) is a short peptide, which could bind to collagen and achieve the sustained release of CBD-fused proteins in collagen scaffold. Here, a collagen-binding EGFR antibody fragment was designed and expressed for targeting the collagen-rich extracellular matrix in tumors. The antibody fragment (Fab) of cetuximab was fused with CBD (CBD-Fab) and expressed in Pichia pastoris. CBD-Fab maintained antigen binding and anti-tumor activity of cetuximab and obtained a collagen-binding ability in vitro. The results also showed CBD-Fab was mainly enriched in tumors and had longer retention time in tumors in A431 s.c. xenografts. Furthermore, CBD-Fab showed a similar therapeutic efficacy as cetuximab in A431 xenografts. Although CBD-Fab hasn't showed better therapeutic effects than cetuximab, its smaller molecular and special target may be applicable as antibody-drug conjugates (ADC) or immunotoxins.

Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies.

PubMed

Zhang, Zhiqing; Li, Shaowei; Gu, Ying; Xia, Ningshao

2016-11-18

Human immunodeficiency virus type 1 (HIV-1) infection causes acquired immune deficiency syndrome (AIDS), a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART) but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs) with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

Characterization of single chain antibody targets through yeast two hybrid

PubMed Central

2010-01-01

Background Due to their unique ability to bind their targets with high fidelity, antibodies are used widely not only in biomedical research, but also in many clinical applications. Recombinant antibodies, including single chain variable fragments (scFv), are gaining momentum because they allow powerful in vitro selection and manipulation without loss of function. Regardless of the ultimate application or type of antibody used, precise understanding of the interaction between the antibody's binding site and its specific target epitope(s) is of great importance. However, such data is frequently difficult to obtain. Results We describe an approach that allows detailed characterization of a given antibody's target(s) using the yeast two-hybrid system. Several recombinant scFv were used as bait and screened against highly complex cDNA libraries. Systematic sequencing of all retained clones and statistical analysis allowed efficient ranking of the prey fragments. Multiple alignment of the obtained cDNA fragments provided a selected interacting domain (SID), efficiently narrowing the epitope-containing region. Interactions between antibodies and their respective targets were characterized for several scFv. For AA2 and ROF7, two conformation-specific sensors that exclusively bind the activated forms of the small GTPases Rab6 and Rab1 respectively, only fragments expressing the entire target protein's core region were retained. This strongly suggested interaction with a non-linear epitope. For two other scFv, TA10 and SF9, which recognize the large proteins giantin and non-muscle myosin IIA, respectively, precise antibody-binding regions within the target were defined. Finally, for some antibodies, secondary targets within and across species could be revealed. Conclusions Our method, utilizing the yeast two-hybrid technology and scFv as bait, is a simple yet powerful approach for the detailed characterization of antibody targets. It allows precise domain mapping for linear

Targeted cancer therapy--are the days of systemic chemotherapy numbered?

PubMed

Joo, Won Duk; Visintin, Irene; Mor, Gil

2013-12-01

Targeted therapy or molecular targeted therapy has been defined as a type of treatment that blocks the growth of cancer cells by interfering with specific cell molecules required for carcinogenesis and tumor growth, rather than by simply interfering with all rapidly dividing cells as with traditional chemotherapy. There is a growing number of FDA approved monoclonal antibodies and small molecules targeting specific types of cancer suggestive of the growing relevance of this therapeutic approach. Targeted cancer therapies, also referred to as "Personalized Medicine", are being studied for use alone, in combination with other targeted therapies, and in combination with chemotherapy. The objective of personalized medicine is the identification of patients that would benefit from a specific treatment based on the expression of molecular markers. Examples of this approach include bevacizumab and olaparib, which have been designated as promising targeted therapies for ovarian cancer. Combinations of trastuzumab with pertuzumab, or T-DM1 and mTOR inhibitors added to an aromatase inhibitor are new therapeutic strategies for breast cancer. Although this approach has been seen as a major step in the expansion of personalized medicine, it has substantial limitations including its high cost and the presence of serious adverse effects. The Cancer Genome Atlas is a useful resource to identify novel and more effective targets, which may help to overcome the present limitations. In this review we will discuss the clinical outcome of some of these new therapies with a focus on ovarian and breast cancer. We will also discuss novel concepts in targeted therapy, the target of cancer stem cells. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Strategies of targeting the extracellular domain of RON tyrosine kinase receptor for cancer therapy and drug delivery.

PubMed

Zarei, Omid; Benvenuti, Silvia; Ustun-Alkan, Fulya; Hamzeh-Mivehroud, Maryam; Dastmalchi, Siavoush

2016-12-01

Cancer is one of the most important life-threatening diseases in the world. The current efforts to combat cancer are being focused on molecular-targeted therapies. The main purpose of such approaches is based on targeting cancer cell-specific molecules to minimize toxicity for the normal cells. RON (Recepteur d'Origine Nantais) tyrosine kinase receptor is one of the promising targets in cancer-targeted therapy and drug delivery. In this review, we will summarize the available agents against extracellular domain of RON with potential antitumor activities. The presented antibodies and antibody drug conjugates against RON in this review showed wide spectrum of in vitro and in vivo antitumor activities promising the hope for them entering the clinical trials. Due to critical role of extracellular domain of RON in receptor activation, the development of therapeutic agents against this region could lead to fruitful outcome in cancer therapy.

Targeted Therapies for Brain Metastases from Breast Cancer.

PubMed

Venur, Vyshak Alva; Leone, José Pablo

2016-09-13

The discovery of various driver pathways and targeted small molecule agents/antibodies have revolutionized the management of metastatic breast cancer. Currently, the major targets of clinical utility in breast cancer include the human epidermal growth factor receptor 2 (HER2) and epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF) receptor, mechanistic target of rapamycin (mTOR) pathway, and the cyclin-dependent kinase 4/6 (CDK-4/6) pathway. Brain metastasis, however, remains a thorn in the flesh, leading to morbidity, neuro-cognitive decline, and interruptions in the management of systemic disease. Approximately 20%-30% of patients with metastatic breast cancer develop brain metastases. Surgery, whole brain radiation therapy, and stereotactic radiosurgery are the traditional treatment options for patients with brain metastases. The therapeutic paradigm is changing due to better understanding of the blood brain barrier and the advent of tyrosine kinase inhibitors and monoclonal antibodies. Several of these agents are in clinical practice and several others are in early stage clinical trials. In this article, we will review the common targetable pathways in the management of breast cancer patients with brain metastases, and the current state of the clinical development of drugs against these pathways.

Advances in targeted therapy for acute myeloid leukaemia.

PubMed

Kayser, Sabine; Levis, Mark J

2018-02-01

In the past few years, research in the underlying pathogenic mechanisms of acute myeloid leukaemia (AML) has led to remarkable advances in our understanding of the disease. Cytogenetic and molecular aberrations are the most important factors in determining response to chemotherapy as well as long-term outcome, but beyond prognostication are potential therapeutic targets. Our increased understanding of the pathogenesis of AML, facilitated by next-generation sequencing, has spurred the development of new compounds in the treatment of AML, particularly the creation of small molecules that target the disease on a molecular level. Various new agents, such as tyrosine kinase inhibitors, immune checkpoint inhibitors, monoclonal or bispecific T-cell engager antibodies, metabolic and pro-apoptotic agents are currently investigated within clinical trials. The highest response rates are often achieved when new molecularly targeted therapies are combined with standard chemotherapy. Presented here is an overview of novel therapies currently being evaluated in AML. © 2017 John Wiley & Sons Ltd.

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

PubMed

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

2014-01-01

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

Selection of phage-displayed accessible recombinant targeted antibodies (SPARTA): methodology and applications.

PubMed

D'Angelo, Sara; Staquicini, Fernanda I; Ferrara, Fortunato; Staquicini, Daniela I; Sharma, Geetanjali; Tarleton, Christy A; Nguyen, Huynh; Naranjo, Leslie A; Sidman, Richard L; Arap, Wadih; Bradbury, Andrew Rm; Pasqualini, Renata

2018-05-03

We developed a potentially novel and robust antibody discovery methodology, termed selection of phage-displayed accessible recombinant targeted antibodies (SPARTA). This combines an in vitro screening step of a naive human antibody library against known tumor targets, with in vivo selections based on tumor-homing capabilities of a preenriched antibody pool. This unique approach overcomes several rate-limiting challenges to generate human antibodies amenable to rapid translation into medical applications. As a proof of concept, we evaluated SPARTA on 2 well-established tumor cell surface targets, EphA5 and GRP78. We evaluated antibodies that showed tumor-targeting selectivity as a representative panel of antibody-drug conjugates (ADCs) and were highly efficacious. Our results validate a discovery platform to identify and validate monoclonal antibodies with favorable tumor-targeting attributes. This approach may also extend to other diseases with known cell surface targets and affected tissues easily isolated for in vivo selection.

ERBB oncogene proteins as targets for monoclonal antibodies.

PubMed

Polanovski, O L; Lebedenko, E N; Deyev, S M

2012-03-01

General properties of the family of tyrosine kinase ERBB receptors are considered in connection with their role in the generation of cascades of signal transduction in normal and tumor cells. Causes of acquisition of oncogene features by genes encoding these receptors and their role in tumorigenesis are analyzed. Anti-ERBB monoclonal antibodies approved for therapy are described in detail, and mechanisms of their antitumor activity and development of resistance to them are reviewed. The existing and the most promising strategies for creating and using monoclonal antibodies and their derivatives for therapy of cancer are discussed.

The emergence of antibody therapies for Ebola.

PubMed

Hiatt, Andrew; Pauly, Michael; Whaley, Kevin; Qiu, Xiangguo; Kobinger, Gary; Zeitlin, Larry

2015-12-23

This review describes the history of Ebola monoclonal antibody (mAb) development leading up to the recent severe Ebola outbreak in West Africa. The Ebola virus has presented numerous perplexing challenges in the long effort to develop therapeutic antibody strategies. Since the first report of a neutralizing human anti-Ebola mAb in 1999, the straightforward progression from in vitro neutralization resulting in in vivo protection and therapy has not occurred. A number of mAbs, including the first reported, failed to protect non-human primates (NHPs) in spite of protection in rodents. An appreciation of the role of effector functions to antibody efficacy has contributed significantly to understanding mechanisms of in vivo protection. However a crucial contribution, as measured by post-exposure therapy of NHPs, involved the comprehensive testing of mAb cocktails. This effort was aided by the use of plant production technology where various combinations of mAbs could be rapidly produced and tested. Introduction of appropriate modifications, such as specific glycan profiles, also improved therapeutic efficacy. The resulting cocktail, ZMapp™, consists of three mAbs that were identified from numerous mAb candidates. ZMapp™ \\ is now being evaluated in human clinical trials but has already played a role in bringing awareness to the potential of antibody therapy for Ebola.

Blister-inducing antibodies target multiple epitopes on collagen VII in mice

PubMed Central

Csorba, Kinga; Chiriac, Mircea Teodor; Florea, Florina; Ghinia, Miruna Georgiana; Licarete, Emilia; Rados, Andreea; Sas, Alexandra; Vuta, Vlad; Sitaru, Cassian

2014-01-01

Epidermolysis bullosa acquisita (EBA) is an autoimmune subepidermal blistering disease of mucous membranes and the skin caused by autoantibodies against collagen VII. In silico and wet laboratory epitope mapping studies revealed numerous distinct epitopes recognized by EBA patients' autoantibodies within the non-collagenous (NC)1 and NC2 domains of collagen VII. However, the distribution of pathogenic epitopes on collagen VII has not yet been described. In this study, we therefore performed an in vivo functional epitope mapping of pathogenic autoantibodies in experimental EBA. Animals (n = 10/group) immunized against fragments of the NC1 and NC2 domains of collagen VII or injected with antibodies generated against the same fragments developed to different extent experimental EBA. Our results demonstrate that antibodies targeting multiple, distinct epitopes distributed over the entire NC1, but not NC2 domain of collagen VII induce blistering skin disease in vivo. Our present findings have crucial implications for the development of antigen-specific B- and T cell-targeted therapies in EBA. PMID:25091020

Successes and limitations of targeted therapies in renal cell carcinoma.

PubMed

Pracht, Marc; Berthold, Dominik

2014-01-01

Until recently, the standard treatment for metastatic renal cell carcinoma (RCC) was nonspecific immunotherapy based on interleukin-2 or interferon-α. This was associated with a modest survival benefit and with significant clinical toxicities. The understanding of numerous molecular pathways in RCC, including HIF, VEGF, mTOR, and the consecutive use of targeted therapies since the beginning of 2005 have significantly improved outcomes for patients with metastatic RCC with an overall survival greater than 2 years. At present, at least 7 targeted agents are approved for first and consecutive lines of treatment of clear cell metastatic RCC. Long-term benefit and extended survival may be achieved through the optimal use of targeted therapies: optimal dosing, adverse event management and treatment duration and compliance. Advances in the finding of prognostic factors highlight the potential for personalizing treatment for patients with metastatic RCC. Data regarding the best sequencing of targeted therapies, predictive biomarkers, best timing of surgery, patient risk profiles, understanding of resistance mechanisms and safety of targeted therapies are growing and will provide a further step ahead in the management of advanced RCC. In parallel, a new class of therapeutics is emerging in RCC: immunotherapy; in particular check-point blockade antibodies are showing very promising results. © 2014 S. Karger AG, Basel.

IBC's 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics international conferences and the 2012 Annual Meeting of The Antibody Society: December 3-6, 2012, San Diego, CA.

PubMed

Klöhn, Peter-Christian; Wuellner, Ulrich; Zizlsperger, Nora; Zhou, Yu; Tavares, Daniel; Berger, Sven; Zettlitz, Kirstin A; Proetzel, Gabriele; Yong, May; Begent, Richard H J; Reichert, Janice M

2013-01-01

The 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics international conferences, and the 2012 Annual Meeting of The Antibody Society, organized by IBC Life Sciences with contributions from The Antibody Society and two Scientific Advisory Boards, were held December 3-6, 2012 in San Diego, CA. The meeting drew over 800 participants who attended sessions on a wide variety of topics relevant to antibody research and development. As a prelude to the main events, a pre-conference workshop held on December 2, 2012 focused on intellectual property issues that impact antibody engineering. The Antibody Engineering Conference was composed of six sessions held December 3-5, 2012: (1) From Receptor Biology to Therapy; (2) Antibodies in a Complex Environment; (3) Antibody Targeted CNS Therapy: Beyond the Blood Brain Barrier; (4) Deep Sequencing in B Cell Biology and Antibody Libraries; (5) Systems Medicine in the Development of Antibody Therapies/Systematic Validation of Novel Antibody Targets; and (6) Antibody Activity and Animal Models. The Antibody Therapeutics conference comprised four sessions held December 4-5, 2012: (1) Clinical and Preclinical Updates of Antibody-Drug Conjugates; (2) Multifunctional Antibodies and Antibody Combinations: Clinical Focus; (3) Development Status of Immunomodulatory Therapeutic Antibodies; and (4) Modulating the Half-Life of Antibody Therapeutics. The Antibody Society's special session on applications for recording and sharing data based on GIATE was held on December 5, 2012, and the conferences concluded with two combined sessions on December 5-6, 2012: (1) Development Status of Early Stage Therapeutic Antibodies; and (2) Immunomodulatory Antibodies for Cancer Therapy.

Antibody targeting facilitates effective intratumoral siRNA nanoparticle delivery to HER2-overexpressing cancer cells

PubMed Central

Palanca-Wessels, Maria C.; Booth, Garrett C.; Convertine, Anthony J.; Lundy, Brittany B.; Berguig, Geoffrey Y.; Press, Michael F.; Stayton, Patrick S.; Press, Oliver W.

2016-01-01

The therapeutic potential of RNA interference (RNAi) has been limited by inefficient delivery of short interfering RNA (siRNA). Tumor-specific recognition can be effectively achieved by antibodies directed against highly expressed cancer cell surface receptors. We investigated the utility of linking an internalizing streptavidin-conjugated HER2 antibody to an endosome-disruptive biotinylated polymeric nanocarrier to improve the functional cytoplasmic delivery of siRNA in breast and ovarian cancer cells in vitro and in an intraperitoneal ovarian cancer xenograft model in vivo, yielding an 80% reduction of target mRNA and protein levels with sustained repression for at least 96 hours. RNAi-mediated site specific cleavage of target mRNA was demonstrated using the 5′ RLM-RACE (RNA ligase mediated-rapid amplification of cDNA ends) assay. Mice bearing intraperitoneal human ovarian tumor xenografts demonstrated increased tumor accumulation of Cy5.5 fluorescently labeled siRNA and 70% target gene suppression after treatment with HER2 antibody-directed siRNA nanocarriers. Detection of the expected mRNA cleavage product by 5′ RLM-RACE assay confirmed that suppression occurs via the expected RNAi pathway. Delivery of siRNA via antibody-directed endosomolytic nanoparticles may be a promising strategy for cancer therapy. PMID:26840082

Antibody targeting facilitates effective intratumoral siRNA nanoparticle delivery to HER2-overexpressing cancer cells.

PubMed

Palanca-Wessels, Maria C; Booth, Garrett C; Convertine, Anthony J; Lundy, Brittany B; Berguig, Geoffrey Y; Press, Michael F; Stayton, Patrick S; Press, Oliver W

2016-02-23

The therapeutic potential of RNA interference (RNAi) has been limited by inefficient delivery of short interfering RNA (siRNA). Tumor-specific recognition can be effectively achieved by antibodies directed against highly expressed cancer cell surface receptors. We investigated the utility of linking an internalizing streptavidin-conjugated HER2 antibody to an endosome-disruptive biotinylated polymeric nanocarrier to improve the functional cytoplasmic delivery of siRNA in breast and ovarian cancer cells in vitro and in an intraperitoneal ovarian cancer xenograft model in vivo, yielding an 80% reduction of target mRNA and protein levels with sustained repression for at least 96 hours. RNAi-mediated site specific cleavage of target mRNA was demonstrated using the 5' RLM-RACE (RNA ligase mediated-rapid amplification of cDNA ends) assay. Mice bearing intraperitoneal human ovarian tumor xenografts demonstrated increased tumor accumulation of Cy5.5 fluorescently labeled siRNA and 70% target gene suppression after treatment with HER2 antibody-directed siRNA nanocarriers. Detection of the expected mRNA cleavage product by 5' RLM-RACE assay confirmed that suppression occurs via the expected RNAi pathway. Delivery of siRNA via antibody-directed endosomolytic nanoparticles may be a promising strategy for cancer therapy.

New targeted therapies for indolent B-cell malignancies in older patients.

PubMed

Krem, Maxwell M; Gopal, Ajay K

2015-01-01

Molecularly targeted agents have become an established component of the treatment of indolent B-cell malignancies (iNHL). iNHL disproportionately affects older adults, so treatments that have excellent tolerability and efficacy across multiple lines of therapy are in demand. The numbers and classes of targeted therapies for iNHL have proliferated rapidly in recent years; classes of agents that show promise for older patients with iNHL include anti-CD20 antibodies, phosphatidyl-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway inhibitors, immunomodulators, proteasome inhibitors, epigenetic modulators, and immunotherapies. Here, we review the proposed mechanisms of action, efficacy, and tolerability of novel agents for iNHL, with an emphasis on their applicability to older patients.

Cbl-independent degradation of Met: ways to avoid agonism of bivalent Met-targeting antibody.

PubMed

Lee, J M; Kim, B; Lee, S B; Jeong, Y; Oh, Y M; Song, Y-J; Jung, S; Choi, J; Lee, S; Cheong, K H; Kim, D U; Park, H W; Han, Y K; Kim, G W; Choi, H; Song, P H; Kim, K A

2014-01-02

The Met receptor tyrosine kinase, found to be constitutively activated in many tumors, has become a leading target for cancer therapy. Disruptions in Met downregulation have been associated with aggressive tumor progression with several therapeutic strategies addressing this aspect of Met biology. Castias B-lineage lymphoma (Cbl) E3 ligase-mediated degradation, which attenuates Met signaling via ligand-dependent Met internalization, is a major negative regulator of Met expression. It is believed that one of the mechanisms by which the therapeutic anti-Met antibodies induce cancer cell death in Met overexpressing tumors is via internalization and subsequent degradation of Met from the cell surface. However, a previously reported Met-targeting antibody demonstrated intrinsic agonistic activity while being capable of inducing Cbl-mediated degradation of Met, suggesting that Cbl-mediated degradation requires receptor activation and impedes therapeutic application. We have developed a potent and selective bivalent Met-targeting antibody (SAIT301) that invokes Met degradation using an alternative regulator LRIG1. In this report, we demonstrate that LRIG1 mediates degradation of Met by SAIT301 and this degradation does not require Met activation. Furthermore, SAIT301 was able to downregulate Met and dramatically inhibit growth of tumors with low or no Cbl expression, as well as tumors with Met exon 14 deletion that prevents Met binding to Cbl. In summary, we demonstrate the enhanced therapeutic potential of a novel tumor-inhibiting anti-Met antibody, SAIT301, which utilizes a Cbl-independent, LRIG1-mediated Met degradation pathway and thereby avoids the agonism that limits the effectiveness of previously reported anti-Met antibodies.

Discovery of functional monoclonal antibodies targeting G-protein-coupled receptors and ion channels.

PubMed

Wilkinson, Trevor C I

2016-06-15

The development of recombinant antibody therapeutics is a significant area of growth in the pharmaceutical industry with almost 50 approved monoclonal antibodies on the market in the US and Europe. Despite this growth, however, certain classes of important molecular targets have remained intractable to therapeutic antibodies due to complexity of the target molecules. These complex target molecules include G-protein-coupled receptors and ion channels which represent a large potential target class for therapeutic intervention with monoclonal antibodies. Although these targets have typically been addressed by small molecule approaches, the exquisite specificity of antibodies provides a significant opportunity to provide selective modulation of these target proteins. Given this opportunity, substantial effort has been applied to address the technical challenges of targeting these complex membrane proteins with monoclonal antibodies. In this review recent progress made in the strategies for discovery of functional monoclonal antibodies for these challenging membrane protein targets is addressed. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

Uncovering the Origin of Skin Side Effects from EGFR-Targeted Therapies | Center for Cancer Research

Cancer.gov

The epidermal growth factor receptor (EGFR), a key regulator of cell proliferation, is often mutated or overexpressed in a variety of cancer types. EGFR-targeted therapies, including monoclonal antibodies and small molecule inhibitors, can effectively treat patients whose tumors depend on aberrant EGFR signaling. Within a few weeks of initiating therapy, however, patients

[Biotherapies, immunotherapies, targeted therapies, biopharmaceuticals… which word should be used?].

PubMed

Watier, Hervé

2014-05-01

The ability to accurately describe and name medical advances is a prerequisite to foster public debates with scientists and physicians, and favour faith over fear among patients and citizens. Therapeutic antibodies are a good example of a medical breakthrough which has met with considerable clinical success, and which terminology has changed over the years. If the appellation serotherapy was appropriate a century ago, it has become obsolete. Recent names such as biotherapy, immunotherapy, targeted therapy, biopharmaceuticals have been introduced and are now commonly used, each of those can apply to therapeutic antibodies. It is thus interesting to question the real meaning of these different appellations. Our goal in this manuscript is to analyse the genesis of these terms but also to suggest how to simplify the terminology: biotherapy or targeted therapy need to be eliminated, as well as immunotherapy when communicating with non scientific public. It is recommended to favour the term biopharmaceuticals (biomédicaments in French), which clearly indicates the origin of these molecules, intermediate between chemical drugs and living biologics, whose borders need to be accurately defined also. © 2014 médecine/sciences – Inserm.

A dual-targeting PDGFRbeta/VEGF-A molecule assembled from stable antibody fragments demonstrates anti-angiogenic activity in vitro and in vivo.

PubMed

Mabry, Robert; Gilbertson, Debra G; Frank, Amanda; Vu, Tuyen; Ardourel, Dan; Ostrander, Craig; Stevens, Brenda; Julien, Susan; Franke, Secil; Meengs, Brent; Brody, Jennifer; Presnell, Scott; Hamacher, Nels B; Lantry, Megan; Wolf, Anitra; Bukowski, Tom; Rosler, Robert; Yen, Cindy; Anderson-Haley, Monica; Brasel, Kenneth; Pan, Qi; Franklin, Hank; Thompson, Penny; Dodds, Mike; Underwood, Sara; Peterson, Scott; Sivakumar, Pallavur V; Snavely, Mark

2010-01-01

Targeting angiogenesis is a promising approach to the treatment of solid tumors and age-related macular degeneration (AMD). Inhibition of vascularization has been validated by the successful marketing of monoclonal antibodies (mAbs) that target specific growth factors or their receptors, but there is considerable room for improvement in existing therapies. Combination of mAbs targeting both the VEGF and PDGF pathways has the potential to increase the efficacy of anti-angiogenic therapy without the accompanying toxicities of tyrosine kinase inhibitors and the inability to combine efficiently with traditional chemotherapeutics. However, development costs and regulatory issues have limited the use of combinatorial approaches for the generation of more efficacious treatments. The concept of mediating disease pathology by targeting two antigens with one therapeutic was proposed over two decades ago. While mAbs are particularly suitable candidates for a dual-targeting approach, engineering bispecificity into one molecule can be difficult due to issues with expression and stability, which play a significant role in manufacturability. Here, we address these issues upstream in the process of developing a bispecific antibody (bsAb). Single-chain antibody fragments (scFvs) targeting PDGFRbeta and VEGF-A were selected for superior stability. The scFvs were fused to both termini of human Fc to generate a bispecific, tetravalent molecule. The resulting molecule displays potent activity, binds both targets simultaneously, and is stable in serum. The assembly of a bsAb using stable monomeric units allowed development of an anti-PDGFRB/VEGF-A antibody capable of attenuating angiogenesis through two distinct pathways and represents an efficient method for rapid engineering of dual-targeting molecules.

Novel Targeted Therapies for Inflammatory Bowel Disease.

PubMed

Coskun, Mehmet; Vermeire, Severine; Nielsen, Ole Haagen

2017-02-01

Our growing understanding of the immunopathogenesis of inflammatory bowel disease (IBD) has opened new avenues for developing targeted therapies. These advances in treatment options targeting different mechanisms of action offer new hope for personalized management. In this review we highlight emerging novel and easily administered therapeutics that may be viable candidates for the management of IBD, such as antibodies against interleukin 6 (IL-6) and IL-12/23, small molecules including Janus kinase inhibitors, antisense oligonucleotide against SMAD7 mRNA, and inhibitors of leukocyte trafficking to intestinal sites of inflammation (e.g., sphingosine 1-phosphate receptor modulators). We also provide an update on the current status in clinical development of these new classes of therapeutics. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Recombinant Secondary Antibody Mimic as a Target-specific Signal Amplifier and an Antibody Immobilizer in Immunoassays.

PubMed

Min, Junseon; Song, Eun Kyung; Kim, Hansol; Kim, Kyoung Taek; Park, Tae Joo; Kang, Sebyung

2016-04-11

We construct a novel recombinant secondary antibody mimic, GST-ABD, which can bind to the Fc regions of target-bound primary antibodies and acquire multiple HRPs simultaneously. We produce it in tenth of mg quantities with a bacterial overexpression system and simple purification procedures, significantly reducing the manufacturing cost and time without the use of animals. GST-ABD is effectively conjugated with 3 HRPs per molecule on an average and selectively bind to the Fc region of primary antibodies derived from three different species (mouse, rabbit, and rat). HRP-conjugated GST-ABD (HRP-GST-ABD) is successfully used as an alternative to secondary antibodies to amplify target-specific signals in both ELISA and immunohistochemistry regardless of the target molecules and origin of primary antibodies used. GST-ABD also successfully serves as an anchoring adaptor on the surface of GSH-coated plates for immobilizing antigen-capturing antibodies in an orientation-controlled manner for sandwich-type indirect ELISA through simple molecular recognition without any complicated chemical modification.

Trojan horses and guided missiles: targeted therapies in the war on arthritis.

PubMed

Ferrari, Mathieu; Onuoha, Shimobi C; Pitzalis, Costantino

2015-06-01

Despite major advances in the treatment of rheumatoid arthritis (RA) led by the success of biologic therapies, the lack of response to therapy in a proportion of patients, as well as therapy discontinuation owing to systemic toxicity, are still unsolved issues. Unchecked RA might develop into progressive structural joint damage, loss of function and long-term disability, disorders which are associated with a considerable health-economic burden. Therefore, new strategies are required to actively target and deliver therapeutic agents to disease sites in order to promote in situ activity and decrease systemic toxicity. Polymer-drug conjugates can improve the pharmacokinetics of therapeutic agents, conferring desirable properties such as increased solubility and tissue penetration at sites of active disease. Additionally, nanotechnology is an exciting modality in which drugs are encapsulated to protect them from degradation or early activation in the circulation, as well as to reduce systemic toxicity. Together with the targeting capacity of antibodies and site-specific peptides, these approaches will facilitate selective accumulation of therapeutic agents in the inflamed synovium, potentially improving drug efficacy at disease sites without affecting healthy tissues. This Review aims to summarize key developments in the past 5 years in polymer conjugation, nanoparticulate drug delivery and antibody or peptide-based targeting--strategies that might constitute the platform for the next generation of RA therapeutics.

Live dynamic imaging of caveolae pumping targeted antibody rapidly and specifically across endothelium in the lung.

PubMed

Oh, Phil; Borgström, Per; Witkiewicz, Halina; Li, Yan; Borgström, Bengt J; Chrastina, Adrian; Iwata, Koji; Zinn, Kurt R; Baldwin, Richard; Testa, Jacqueline E; Schnitzer, Jan E

2007-03-01

How effectively and quickly endothelial caveolae can transcytose in vivo is unknown, yet critical for understanding their function and potential clinical utility. Here we use quantitative proteomics to identify aminopeptidase P (APP) concentrated in caveolae of lung endothelium. Electron microscopy confirms this and shows that APP antibody targets nanoparticles to caveolae. Dynamic intravital fluorescence microscopy reveals that targeted caveolae operate effectively as pumps, moving antibody within seconds from blood across endothelium into lung tissue, even against a concentration gradient. This active transcytosis requires normal caveolin-1 expression. Whole body gamma-scintigraphic imaging shows rapid, specific delivery into lung well beyond that achieved by standard vascular targeting. This caveolar trafficking in vivo may underscore a key physiological mechanism for selective transvascular exchange and may provide an enhanced delivery system for imaging agents, drugs, gene-therapy vectors and nanomedicines. 'In vivo proteomic imaging' as described here integrates organellar proteomics with multiple imaging techniques to identify an accessible target space that includes the transvascular pumping space of the caveola.

Engineering multivalent antibodies to target heregulin-induced HER3 signaling in breast cancer cells

PubMed Central

Kang, Jeffrey C; Poovassery, Jayakumar S; Bansal, Pankaj; You, Sungyong; Manjarres, Isabel M; Ober, Raimund J; Ward, E Sally

2014-01-01

The use of antibodies in therapy and diagnosis has undergone an unprecedented expansion during the past two decades. This is due in part to innovations in antibody engineering that now offer opportunities for the production of “second generation” antibodies with multiple specificities or altered valencies. The targeting of individual components of the human epidermal growth factor receptor (HER)3-PI3K signaling axis, including the preferred heterodimerization partner HER2, is known to have limited anti-tumor effects. The efficacy of antibodies or small molecule tyrosine kinase inhibitors (TKIs) in targeting this axis is further reduced by the presence of the HER3 ligand, heregulin. To address these shortcomings, we performed a comparative analysis of two distinct approaches toward reducing the proliferation and signaling in HER2 overexpressing tumor cells in the presence of heregulin. These strategies both involve the use of engineered antibodies in combination with the epidermal growth factor receptor (EGFR)/HER2 specific TKI, lapatinib. In the first approach, we generated a bispecific anti-HER2/HER3 antibody that, in the presence of lapatinib, is designed to sequester HER3 into inactive HER2-HER3 dimers that restrain HER3 interactions with other possible dimerization partners. The second approach involves the use of a tetravalent anti-HER3 antibody with the goal of inducing efficient HER3 internalization and degradation. In combination with lapatinib, we demonstrate that although the multivalent HER3 antibody is more effective than its bivalent counterpart in reducing heregulin-mediated signaling and growth, the bispecific HER2/HER3 antibody has increased inhibitory activity. Collectively, these observations provide support for the therapeutic use of bispecifics in combination with TKIs to recruit HER3 into complexes that are functionally inert. PMID:24492289

Antibody-drug conjugates for cancer therapy: The technological and regulatory challenges of developing drug-biologic hybrids.

PubMed

Hamilton, Gregory S

2015-09-01

Antibody-drug conjugates (ADCs) are a new class of therapeutic agents that combine the targeting ability of monoclonal antibodies (mAbs) with small molecule drugs. The combination of a mAb targeting a cancer-specific antigen with a cytotoxin has tremendous promise as a new type of targeted cancer therapy. Two ADCs have been approved and many more are in clinical development, suggesting that this new class of drugs is coming to the forefront. Because of their unique nature as biologic-small drug hybrids, ADCs are challenging to develop, from both the scientific and regulatory perspectives. This review discusses both these aspects in current practice, and surveys the current state of the art of ADC drug development. Copyright © 2015 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

Molecular targeted therapies for solid tumors: management of side effects.

PubMed

Grünwald, Viktor; Soltau, Jens; Ivanyi, Philipp; Rentschler, Jochen; Reuter, Christoph; Drevs, Joachim

2009-03-01

This review will provide physicians and oncologists with an overview of side effects related to targeted agents that inhibit vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and mammalian target of rapamycin (mTOR) signaling in the treatment of solid tumors. Such targeted agents can be divided into monoclonal antibodies, tyrosine kinase inhibitors, multitargeted tyrosine kinase inhibitors and serine/threonine kinase inhibitors. Molecular targeted therapies are generally well tolerated, but inhibitory effects on the biological function of the targets in healthy tissue can result in specific treatment-related side effects, particularly with multitargeted agents. We offer some guidance on how to manage adverse events in cancer patients based on the range of options currently available. Copyright 2009 S. Karger AG, Basel.

Functional single-walled carbon nanotubes based on an integrin αvβ3 monoclonal antibody for highly efficient cancer cell targeting

NASA Astrophysics Data System (ADS)

Ou, Zhongmin; Wu, Baoyan; Xing, Da; Zhou, Feifan; Wang, Huiying; Tang, Yonghong

2009-03-01

The application of single-walled carbon nanotubes (SWNTs) in the field of biomedicine is becoming an entirely new and exciting topic. In this study, a novel functional SWNT based on an integrin αvβ3 monoclonal antibody was developed and was used for cancer cell targeting in vitro. SWNTs were first modified by phospholipid-bearing polyethylene glycol (PL-PEG). The PL-PEG functionalized SWNTs were then conjugated with protein A. A SWNT-integrin αvβ3 monoclonal antibody system (SWNT-PEG-mAb) was thus constructed by conjugating protein A with the fluorescein labeled integrin αvβ3 monoclonal antibody. In vitro study revealed that SWNT-PEG-mAb presented a high targeting efficiency on integrin αvβ3-positive U87MG cells with low cellular toxicity, while for integrin αvβ3-negative MCF-7 cells, the system had a low targeting efficiency, indicating that the high targeting to U87MG cells was due to the specific integrin targeting of the monoclonal antibody. In conclusion, SWNT-PEG-mAb developed in this research is a potential candidate for cancer imaging and drug delivery in cancer targeting therapy.

A collagen-binding EGFR antibody fragment targeting tumors with a collagen-rich extracellular matrix

PubMed Central

Liang, Hui; Li, Xiaoran; Wang, Bin; Chen, Bing; Zhao, Yannan; Sun, Jie; Zhuang, Yan; Shi, Jiajia; Shen, He; Zhang, Zhijun; Dai, Jianwu

2016-01-01

Many tumors over-express collagen, which constitutes the physical scaffold of tumor microenvironment. Collagen has been considered to be a target for cancer therapy. The collagen-binding domain (CBD) is a short peptide, which could bind to collagen and achieve the sustained release of CBD-fused proteins in collagen scaffold. Here, a collagen-binding EGFR antibody fragment was designed and expressed for targeting the collagen-rich extracellular matrix in tumors. The antibody fragment (Fab) of cetuximab was fused with CBD (CBD-Fab) and expressed in Pichia pastoris. CBD-Fab maintained antigen binding and anti-tumor activity of cetuximab and obtained a collagen-binding ability in vitro. The results also showed CBD-Fab was mainly enriched in tumors and had longer retention time in tumors in A431 s.c. xenografts. Furthermore, CBD-Fab showed a similar therapeutic efficacy as cetuximab in A431 xenografts. Although CBD-Fab hasn’t showed better therapeutic effects than cetuximab, its smaller molecular and special target may be applicable as antibody–drug conjugates (ADC) or immunotoxins. PMID:26883295

Genetically engineered multivalent single chain antibody constructs for cancer therapy

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

Surinder Batra, Ph D

2006-02-27

Current therapeutic approaches against the advanced stages of human solid tumors are palliative rather than curative. Many modalities, including, surgery, radiation, and chemotherapy, either alone or in combination have met with only modest success for advanced metastatic cancers. Radioimmunotherapy (RIT) combines the specificity of monoclonal antibodies with cytotxic effects of radioisotopes. It is the smart way of delivering radiation to the known and occult metastatic cancer cells and is independent of drug toxicity and/or hormone resistance. The tumor associated glycoprotein-72 (TAG-72) containing the unique disaccharide sialyl-Tn, is highly expressed in majority of adenocarcinomas, including carcinomas of the prostate, breast, ovaries,more » pancreas and colon (80-90%) compared to undetectable expression in normal tissues. Monoclonal antibody CC49, reactive with TAG-72, after conjugation to potent gamma- and beta-emitting radionuclides, has been useful in selective systemic radiolocalization of disease and therapy of primary and metastatic tumor sites. However, limited therapeutic responses were observed in patients. Limited success of antibody based delivery of radioisotopes can be attributed to several factors including undesirable pharmacokinetics, poor tumor uptake and high immunogenicity of intact antibodies (IgGs). The primary factors contributing towards the failure of RIT include: 1) longer serum half-lives of the intact IgG molecules resulting in the radiotoxicity, 2) generation of human antibodies against murine antibodies (HAMA) that limits the frequency of dose administration, 3) poor diffusion rates of intact IgG due to the large size and 4) high interstitial fluid pressures (IFP) encountered in solid tumors. The major goal of our multidisciplinary project was to develop specific novel radiopharmaceuticals, with desired pharmacokinetics, for the diagnosis and therapy of solid tumors. To overcome the low uptake of radioactivity by tumors and to

Targeted therapies in hepatocellular carcinoma.

PubMed

Bronte, F; Bronte, G; Cusenza, S; Fiorentino, E; Rolfo, C; Cicero, G; Bronte, E; Di Marco, V; Firenze, A; Angarano, G; Fontana, T; Russo, A

2014-01-01

The onset of hepatocellular carcinoma (HCC) is related to the development of non-neoplastic liver disease, such as viral infections and cirrhosis. Even though patients with chronic liver diseases undergo clinical surveillance for early diagnosis of HCC, this cancer is often diagnosed in advanced stage. In this case locoregional treatment is not possible and systemic therapies are the best way to control it. Until now sorafenib, a Raf and multi-kinase inhibitor has been the best, choice to treat HCC systemically. It showed a survival benefit in multicenter phase III trials. However the proper patient setting to treat is not well defined, since the results in Child-Pugh B patients are conflicting. To date various new target drugs are under developed and other biological treatments normally indicated in other malignancies are under investigation also for HCC. These strategies aim to target the different biological pathways implicated in HCC development and progression. The target drugs studied in HCC include anti-VEGF and anti-EGFR monoclonal antibodies, tyrosine kinase inhibitors and mTOR inhibitors. The most important challenge is represented by the best integration of these drugs with standard treatments to achieve improvement in overall survival and quality of life.

Human IgG1 antibodies suppress angiogenesis in a target-independent manner

PubMed Central

Bogdanovich, Sasha; Kim, Younghee; Mizutani, Takeshi; Yasuma, Reo; Tudisco, Laura; Cicatiello, Valeria; Bastos-Carvalho, Ana; Kerur, Nagaraj; Hirano, Yoshio; Baffi, Judit Z; Tarallo, Valeria; Li, Shengjian; Yasuma, Tetsuhiro; Arpitha, Parthasarathy; Fowler, Benjamin J; Wright, Charles B; Apicella, Ivana; Greco, Adelaide; Brunetti, Arturo; Ruvo, Menotti; Sandomenico, Annamaria; Nozaki, Miho; Ijima, Ryo; Kaneko, Hiroki; Ogura, Yuichiro; Terasaki, Hiroko; Ambati, Balamurali K; Leusen, Jeanette HW; Langdon, Wallace Y; Clark, Michael R; Armour, Kathryn L; Bruhns, Pierre; Verbeek, J Sjef; Gelfand, Bradley D; De Falco, Sandro; Ambati, Jayakrishna

2016-01-01

Aberrant angiogenesis is implicated in diseases affecting nearly 10% of the world’s population. The most widely used anti-angiogenic drug is bevacizumab, a humanized IgG1 monoclonal antibody that targets human VEGFA. Although bevacizumab does not recognize mouse Vegfa, it inhibits angiogenesis in mice. Here we show bevacizumab suppressed angiogenesis in three mouse models not via Vegfa blockade but rather Fc-mediated signaling through FcγRI (CD64) and c-Cbl, impairing macrophage migration. Other approved humanized or human IgG1 antibodies without mouse targets (adalimumab, alemtuzumab, ofatumumab, omalizumab, palivizumab and tocilizumab), mouse IgG2a, and overexpression of human IgG1-Fc or mouse IgG2a-Fc, also inhibited angiogenesis in wild-type and FcγR humanized mice. This anti-angiogenic effect was abolished by Fcgr1 ablation or knockdown, Fc cleavage, IgG-Fc inhibition, disruption of Fc-FcγR interaction, or elimination of FcRγ-initated signaling. Furthermore, bevacizumab’s Fc region potentiated its anti-angiogenic activity in humanized VEGFA mice. Finally, mice deficient in FcγRI exhibited increased developmental and pathological angiogenesis. These findings reveal an unexpected anti-angiogenic function for FcγRI and a potentially concerning off-target effect of hIgG1 therapies. PMID:26918197

Dual combination therapy targeting DR5 and EMMPRIN in pancreatic adenocarcinoma.

PubMed

Kim, Hyunki; Zhai, Guihua; Samuel, Sharon L; Rigell, Christopher J; Umphrey, Heidi R; Rana, Samir; Stockard, Cecil R; Fineberg, Naomi S; Zinn, Kurt R

2012-02-01

The goal of the study was to assess the efficacy of combined extracellular matrix metalloprotease inducer (EMMPRIN)- and death receptor 5 (DR5)-targeted therapy for pancreatic adenocarcinoma in orthotopic mouse models with multimodal imaging. Cytotoxicity of anti-EMMPRIN antibody and anti-DR5 antibody (TRA-8) in MIA PaCa-2 and PANC-1 cell lines was measured by ATPlite assay in vitro. The distributions of Cy5.5-labeled TRA-8 and Cy3-labeled anti-EMMPRIN antibody in the 2 cell lines were analyzed by fluorescence imaging in vitro. Groups 1 to 12 of severe combined immunodeficient mice bearing orthotopic MIA PaCa-2 (groups 1-8) or PANC-1 (groups 9-12) tumors were used for in vivo studies. Dynamic contrast-enhanced-MRI was applied in group 1 (untreated) or group 2 (anti-EMMPRIN antibody). The tumor uptake of Tc-99m-labeled TRA-8 was measured in group 3 (untreated) and group 4 (anti-EMMPRIN antibody). Positron emission tomography/computed tomography imaging with (18)F-FDG was applied in groups 5 to 12. Groups 5 to 8 (or groups 9 to 12) were untreated or treated with anti-EMMPRIN antibody, TRA-8, and combination, respectively. TRA-8 showed high killing efficacy for both MIA PaCa-2 and PANC-1 cells in vitro, but additional anti-EMMPRIN treatment did not improve the cytotoxicity. Cy5.5-TRA-8 formed cellular caps in both the cell lines, whereas the maximum signal intensity was correlated with TRA-8 cytotoxicity. Anti-EMMPRIN therapy significantly enhanced the tumor delivery of the MR contrast agent, but not Tc-99m-TRA-8. Tumor growth was significantly suppressed by the combination therapy, and the additive effect of the combination was shown in both MIA PaCa-2 and PANC-1 tumor models.

Targeted Therapies in Hematology and Their Impact on Patient Care: Chronic and Acute Myeloid Leukemia

PubMed Central

Cortes, Elias Jabbour Jorge; Ravandi, Farhad; O’Brien, Susan; Kantarjian, Hagop

2014-01-01

Advances in the genetic and molecular characterizations of leukemias have enhanced our capabilities to develop targeted therapies. The most dramatic examples of targeted therapy in cancer to date are the use of targeted BCR-ABL protein tyrosine kinase inhibitors (TKI) which has revolutionized the treatment of chronic myeloid leukemia (CML). Inhibition of the signaling activity of this kinase has proved to be a highly successful treatment target, transforming the prognosis of patients with CML. In contrast, acute myeloid leukemia (AML) is an extremely heterogeneous disease with outcomes that vary widely according to subtype of the disease. Targeted therapy with monoclonal antibodies and small molecule kinase inhibitors are promising strategies to help improve the cure rates in AML. In this review, we will highlight the results of recent clinical trials in which outcomes of CML and AML have been influenced significantly. Also, novel approaches to sequencing and combining available therapies will be covered. PMID:24246694

In vivo targeting and imaging of tumor vasculature with radiolabeled, antibody-conjugated nanographene.

PubMed

Hong, Hao; Yang, Kai; Zhang, Yin; Engle, Jonathan W; Feng, Liangzhu; Yang, Yunan; Nayak, Tapas R; Goel, Shreya; Bean, Jero; Theuer, Charles P; Barnhart, Todd E; Liu, Zhuang; Cai, Weibo

2012-03-27

Herein we demonstrate that nanographene can be specifically directed to the tumor neovasculature in vivo through targeting of CD105 (i.e., endoglin), a vascular marker for tumor angiogenesis. The covalently functionalized nanographene oxide (GO) exhibited excellent stability and target specificity. Pharmacokinetics and tumor targeting efficacy of the GO conjugates were investigated with serial noninvasive positron emission tomography imaging and biodistribution studies, which were validated by in vitro, in vivo, and ex vivo experiments. The incorporation of an active targeting ligand (TRC105, a monoclonal antibody that binds to CD105) led to significantly improved tumor uptake of functionalized GO, which was specific for the neovasculature with little extravasation, warranting future investigation of these GO conjugates for cancer-targeted drug delivery and/or photothermal therapy to enhance therapeutic efficacy. Since poor extravasation is a major hurdle for nanomaterial-based tumor targeting in vivo, this study also establishes CD105 as a promising vascular target for future cancer nanomedicine. © 2012 American Chemical Society

Application of molecular targeted therapies in the treatment of head and neck squamous cell carcinoma.

PubMed

Kozakiewicz, Paulina; Grzybowska-Szatkowska, Ludmiła

2018-05-01

Despite the development of standard therapies, including surgery, radiotherapy and chemotherapy, survival rates for head and neck squamous cell carcinoma (HNSCC) have not changed significantly over the past three decades. Complete recovery is achieved in <50% of patients. The treatment of advanced HNSCC frequently requires multimodality therapy and involves significant toxicity. The promising, novel treatment option for patients with HNSCC is molecular-targeted therapies. The best known targeted therapies include: Epidermal growth factor receptor (EGFR) monoclonal antibodies (cetuximab, panitumumab, zalutumumab and nimotuzumab), EGFR tyrosine kinase inhibitors (gefitinib, erlotinib, lapatinib, afatinib and dacomitinib), vascular endothelial growth factor (VEGF) inhibitor (bevacizumab) or vascular endothelial growth factor receptor (VEGFR) inhibitors (sorafenib, sunitinib and vandetanib) and inhibitors of phosphatidylinositol 3-kinase/serine/threonine-specific protein kinase/mammalian target of rapamycin. There are also various inhibitors of other pathways and targets, which are promising and require evaluation in further studies.

Adoptive therapy with CAR redirected T cells: the challenges in targeting solid tumors.

PubMed

Abken, Hinrich

2015-01-01

Recent spectacular success in the adoptive cell therapy of leukemia and lymphoma with chimeric antigen receptor (CAR)-modified T cells raised the expectations that this therapy may be efficacious in a wide range of cancer entities. The expectations are based on the predefined specificity of CAR T cells by an antibody-derived binding domain that acts independently of the natural T-cell receptor, recognizes targets independently of presentation by the major histocompatibility complex and allows targeting toward virtually any cell surface antigen. We here discuss that targeting CAR T cells toward solid tumors faces certain circumstances critical for the therapeutic success. Targeting tumor stroma and taking advantage of TRUCK cells, in other words, CAR T cells with inducible release of a transgenic payload, are some strategies envisaged to overcome current limitations in the near future.

Computational selection of antibody-drug conjugate targets for breast cancer

PubMed Central

Fauteux, François; Hill, Jennifer J.; Jaramillo, Maria L.; Pan, Youlian; Phan, Sieu; Famili, Fazel; O'Connor-McCourt, Maureen

2016-01-01

The selection of therapeutic targets is a critical aspect of antibody-drug conjugate research and development. In this study, we applied computational methods to select candidate targets overexpressed in three major breast cancer subtypes as compared with a range of vital organs and tissues. Microarray data corresponding to over 8,000 tissue samples were collected from the public domain. Breast cancer samples were classified into molecular subtypes using an iterative ensemble approach combining six classification algorithms and three feature selection techniques, including a novel kernel density-based method. This feature selection method was used in conjunction with differential expression and subcellular localization information to assemble a primary list of targets. A total of 50 cell membrane targets were identified, including one target for which an antibody-drug conjugate is in clinical use, and six targets for which antibody-drug conjugates are in clinical trials for the treatment of breast cancer and other solid tumors. In addition, 50 extracellular proteins were identified as potential targets for non-internalizing strategies and alternative modalities. Candidate targets linked with the epithelial-to-mesenchymal transition were identified by analyzing differential gene expression in epithelial and mesenchymal tumor-derived cell lines. Overall, these results show that mining human gene expression data has the power to select and prioritize breast cancer antibody-drug conjugate targets, and the potential to lead to new and more effective cancer therapeutics. PMID:26700623

Single-Cell Droplet Microfluidic Screening for Antibodies Specifically Binding to Target Cells.

PubMed

Shembekar, Nachiket; Hu, Hongxing; Eustace, David; Merten, Christoph A

2018-02-20

Monoclonal antibodies are a main player in modern drug discovery. Many antibody screening formats exist, each with specific advantages and limitations. Nonetheless, it remains challenging to screen antibodies for the binding of cell-surface receptors (the most important class of all drug targets) or for the binding to target cells rather than purified proteins. Here, we present a high-throughput droplet microfluidics approach employing dual-color normalized fluorescence readout to detect antibody binding. This enables us to obtain quantitative data on target cell recognition, using as little as 33 fg of IgG per assay. Starting with an excess of hybridoma cells releasing unspecific antibodies, individual clones secreting specific binders (of target cells co-encapsulated into droplets) could be enriched 220-fold after sorting 80,000 clones in a single experiment. This opens the way for therapeutic antibody discovery, especially since the single-cell approach is in principle also applicable to primary human plasma cells. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Antibody-mediated rejection across solid organ transplants: manifestations, mechanisms, and therapies.

PubMed

Valenzuela, Nicole M; Reed, Elaine F

2017-06-30

Solid organ transplantation is a curative therapy for hundreds of thousands of patients with end-stage organ failure. However, long-term outcomes have not improved, and nearly half of transplant recipients will lose their allografts by 10 years after transplant. One of the major challenges facing clinical transplantation is antibody-mediated rejection (AMR) caused by anti-donor HLA antibodies. AMR is highly associated with graft loss, but unfortunately there are few efficacious therapies to prevent and reverse AMR. This Review describes the clinical and histological manifestations of AMR, and discusses the immunopathological mechanisms contributing to antibody-mediated allograft injury as well as current and emerging therapies.

Phage display-derived human antibodies in clinical development and therapy.

PubMed

Frenzel, André; Schirrmann, Thomas; Hust, Michael

2016-10-01

Over the last 3 decades, monoclonal antibodies have become the most important class of therapeutic biologicals on the market. Development of therapeutic antibodies was accelerated by recombinant DNA technologies, which allowed the humanization of murine monoclonal antibodies to make them more similar to those of the human body and suitable for a broad range of chronic diseases like cancer and autoimmune diseases. In the early 1990s in vitro antibody selection technologies were developed that enabled the discovery of "fully" human antibodies with potentially superior clinical efficacy and lowest immunogenicity. Antibody phage display is the first and most widely used of the in vitro selection technologies. It has proven to be a robust, versatile platform technology for the discovery of human antibodies and a powerful engineering tool to improve antibody properties. As of the beginning of 2016, 6 human antibodies discovered or further developed by phage display were approved for therapy. In 2002, adalimumab (Humira®) became the first phage display-derived antibody granted a marketing approval. Humira® was also the first approved human antibody, and it is currently the best-selling antibody drug on the market. Numerous phage display-derived antibodies are currently under advanced clinical investigation, and, despite the availability of other technologies such as human antibody-producing transgenic mice, phage display has not lost its importance for the discovery and engineering of therapeutic antibodies. Here, we provide a comprehensive overview about phage display-derived antibodies that are approved for therapy or in clinical development. A selection of these antibodies is described in more detail to demonstrate different aspects of the phage display technology and its development over the last 25 years.

Antibody Fragments as Potential Biopharmaceuticals for Cancer Therapy: Success and Limitations.

PubMed

Kholodenko, Roman V; Kalinovsky, Daniel V; Doronin, Igor I; Ponomarev, Eugene D; Kholodenko, Irina V

2017-08-17

Monoclonal antibodies (mAbs) are an important class of therapeutic agents approved for the therapy of many types of malignancies. However, in certain cases applications of conventional mAbs have several limitations in anticancer immunotherapy. These limitations include insufficient efficacy and adverse effects. The antigen-binding fragments of antibodies have a considerable potential to overcome the disadvantages of conventional mAbs, such as poor penetration into solid tumors and Fc-mediated bystander activation of the immune system. Fragments of antibodies retain antigen specificity and part of functional properties of conventional mAbs and at the same time have much better penetration into the tumors and a greatly reduced level of adverse effects. Recent advantages in antibody engineering allowed to produce different types of antibody fragments with improved structure and properties for efficient elimination of tumor cells. These molecules opened up new perspectives for anticancer therapy. Here we will overview the structural features of the various types of antibody fragments and their applications for anticancer therapy as separate molecules and as part of complex conjugates or structures. Mechanisms of antitumor action of antibody fragments as well as their advantages and disadvantages for clinical application will be discussed in this review. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

3β-Hydroxysterol Δ24-Reductase on the Surface of Hepatitis C Virus-Related Hepatocellular Carcinoma Cells Can Be a Target for Molecular Targeting Therapy

PubMed Central

Saito, Makoto; Takano, Takashi; Nishimura, Tomohiro; Kohara, Michinori; Tsukiyama-Kohara, Kyoko

2015-01-01

In our previous study, we demonstrated that 3β-hydroxysterol Δ24-reductase (DHCR24) was overexpressed in hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC), and that its expression was induced by HCV. Using a monoclonal antibody against DHCR24 (2-152a MAb), we found that DHCR24 was specifically expressed on the surface of HCC cell lines. Based on these findings, we aimed to establish a novel targeting strategy using 2-152a MAb to treat HCV-related HCC. In the present study, we examined the antitumor activity of 2-152a MAb. In the presence of complement, HCC-derived HuH-7 cells were killed by treatment with 2-152a MAb, which was mediated by complement-dependent cytotoxicity (CDC). In addition, the antigen recognition domain of 2-152a MAb was responsible for the unique anti-HCV activity. These findings demonstrate the feasibility of using 2-152a MAb for antibody therapy against HCV-related HCC. In addition, surface DHCR24 on HCC cells exhibited a functional property, agonist-induced internalization. We showed that 2-152a MAb-mediated binding of a cytotoxic agent (a saponin-conjugated secondary antibody) to surface DHCR24 led to significant cytotoxicity. This suggests that surface DHCR24 on HCC cells can function as a carrier for internalization. Therefore, surface DHCR24 could be a valuable target for HCV-related HCC therapy, and 2-152a MAb appears to be useful for this targeted therapy. PMID:25875901

Targeted Therapy for Cancer

Cancer.gov

Targeted therapy is a type of cancer treatment that targets the changes in cancer cells that help them grow, divide, and spread. Learn how targeted therapy works against cancer and about side effects that may occur.

Targeting IL-5Rα with antibody-conjugates reveals a strategy for imaging and therapy for invasive bladder cancer.

PubMed

Paquette, Michel; Vilera-Perez, Luis-Guillermo; Beaudoin, Simon; Ekindi-Ndongo, Nadia; Boudreaut, Pierre-Luc; Bonin, Marc-Andre; Battista, Marie-Claude; Bentourkia, M'hamed; Lopez, Angel F; Lecomte, Roger; Marsault, Eric; Guérin, Brigitte; Sabbagh, Robert; Leyton, Jeffrey V

2017-01-01

Despite the high interest and concern due to an increasing incidence and death rate, patients who develop muscle invasive bladder cancer (MIBC) have few options available. However, the past decade has produced many candidate bladder tumor-specific markers but further development of these markers is still needed for creating effective targeted medications to solve this urgent need. Interleukin-5 receptor α-subunit (IL-5Rα) has recently been reported to be involved in MIBC progression. Thus, we aimed to validate IL-5Rα as a target for antibody-conjugates to better manage patients with MIBC. Patients were recruited and their tumors were processed for IL-5Rα immunohistochemical analysis. NOD/SCID mice were also heterotopically implanted with the human MIBC HT-1376 and HT-B9 cell lines and established xenografts immunohistochemically evaluated for IL-5Rα and compared against patient tumors. Using the mAb A14, an antibody-drug conjugate (ADC) and a radiolabeled immunoconjugate (RIC) were developed by conjugating to vinblastine and to the positron emitter copper-64 ( 64 Cu), respectively. As a proof-of-concept for ADC and RIC efficacy, in vitro cytotoxicity and in vivo positron emission tomography (PET) imaging in tumor-bearing mice were performed, respectively. In addition, as rapid internalization and accumulation are important components for effective antibody-conjugates, we evaluated these aspects in response to IL-5 and 64 Cu-A14 treatments. Our findings suggest that although IL-5Rα protein expression is preferentially increased in MIBC, it is rapid IL-5Rα-mediated internalization allowing vinblastine-A14 to have cytotoxic activity and 64 Cu-A14 to detect MIBC tumors in vivo . This is the first report to elucidate the potential of IL-5Rα as an attractive MIBC target for antibody-conjugate applications.

Targeting IL-5Rα with antibody-conjugates reveals a strategy for imaging and therapy for invasive bladder cancer

PubMed Central

Vilera-Perez, Luis-Guillermo; Beaudoin, Simon; Ekindi-Ndongo, Nadia; Boudreaut, Pierre-Luc; Bonin, Marc-Andre; Battista, Marie-Claude; Bentourkia, M'hamed; Lopez, Angel F.; Lecomte, Roger; Marsault, Eric; Sabbagh, Robert; Leyton, Jeffrey V.

2017-01-01

ABSTRACT Despite the high interest and concern due to an increasing incidence and death rate, patients who develop muscle invasive bladder cancer (MIBC) have few options available. However, the past decade has produced many candidate bladder tumor-specific markers but further development of these markers is still needed for creating effective targeted medications to solve this urgent need. Interleukin-5 receptor α-subunit (IL-5Rα) has recently been reported to be involved in MIBC progression. Thus, we aimed to validate IL-5Rα as a target for antibody-conjugates to better manage patients with MIBC. Patients were recruited and their tumors were processed for IL-5Rα immunohistochemical analysis. NOD/SCID mice were also heterotopically implanted with the human MIBC HT-1376 and HT-B9 cell lines and established xenografts immunohistochemically evaluated for IL-5Rα and compared against patient tumors. Using the mAb A14, an antibody-drug conjugate (ADC) and a radiolabeled immunoconjugate (RIC) were developed by conjugating to vinblastine and to the positron emitter copper-64 (64Cu), respectively. As a proof-of-concept for ADC and RIC efficacy, in vitro cytotoxicity and in vivo positron emission tomography (PET) imaging in tumor-bearing mice were performed, respectively. In addition, as rapid internalization and accumulation are important components for effective antibody-conjugates, we evaluated these aspects in response to IL-5 and 64Cu-A14 treatments. Our findings suggest that although IL-5Rα protein expression is preferentially increased in MIBC, it is rapid IL-5Rα-mediated internalization allowing vinblastine-A14 to have cytotoxic activity and 64Cu-A14 to detect MIBC tumors in vivo. This is the first report to elucidate the potential of IL-5Rα as an attractive MIBC target for antibody-conjugate applications. PMID:29123949

Sclerostin Antibody Therapy for the Treatment of Osteoporosis: Clinical Prospects and Challenges

PubMed Central

MacNabb, Claire; Patton, D.; Hayes, J. S.

2016-01-01

It is estimated that over 200 million adults worldwide have osteoporosis, a disease that has increasing socioeconomic impact reflected by unsustainable costs associated with disability, fracture management, hospital stays, and treatment. Existing therapeutic treatments for osteoporosis are associated with a variety of issues relating to use, clinical predictability, and health risks. Consequently, additional novel therapeutic targets are increasingly sought. A promising therapeutic candidate is sclerostin, a Wnt pathway antagonist and, as such, a negative regulator of bone formation. Sclerostin antibody treatment has demonstrated efficacy and superiority compared to other anabolic treatments for increasing bone formation in both preclinical and clinical settings. Accordingly, it has been suggested that sclerostin antibody treatment is set to achieve market approval by 2017 and aggressively compete as the gold standard for osteoporotic treatment by 2021. In anticipation of phase III trial results which may potentially signify a significant step in achieving market approval here, we review the preclinical and clinical emergence of sclerostin antibody therapies for both osteoporosis and alternative applications. Potential clinical challenges are also explored as well as ongoing developments that may impact on the eventual clinical application of sclerostin antibodies as an effective treatment of osteoporosis. PMID:27313945

Financial relationships in economic analyses of targeted therapies in oncology.

PubMed

Valachis, Antonis; Polyzos, Nikolaos P; Nearchou, Andreas; Lind, Pehr; Mauri, Davide

2012-04-20

A potential financial relationship between investigators and pharmaceutical manufacturers has been associated with an increased likelihood of reporting favorable conclusions about a sponsor's proprietary agent in pharmacoeconomic studies. The purpose of this study is to investigate whether there is an association between financial relationships and outcome in economic analyses of new targeted therapies in oncology. We searched PubMed (last update June 2011) for economic analyses of targeted therapies (including monoclonal antibodies, tyrosine-kinase inhibitors, and mammalian target of rapamycin inhibitors) in oncology. The trials were qualitatively rated regarding the cost assessment as favorable, neutral, or unfavorable on the basis of prespecified criteria. Overall, 81 eligible studies were identified. Economic analyses that were funded by pharmaceutical companies were more likely to report favorable qualitative cost estimates (28 [82%] of 34 v 21 [45%] of 47; P = .003). The presence of an author affiliated with manufacturer was not associated with study outcome. Furthermore, if only studies including a conflict of interest statement were included (66 of 81), studies that reported any financial relationship with manufacturers (author affiliation and/or funding and/or other financial relationship) were more likely to report favorable results of targeted therapies compared with studies without financial relationship (32 [71%] of 45 v nine [43%] of 21; P = .025). Our study reveals a potential threat for industry-related bias in economic analyses of targeted therapies in oncology in favor of analyses with financial relationships between authors and manufacturers. A more balanced funding of economic analyses from other sources may allow greater confidence in the interpretation of their results.

Antibody Desensitization Therapy in Highly Sensitized Lung Transplant Candidates

PubMed Central

Snyder, L. D.; Gray, A. L.; Reynolds, J. M.; Arepally, G. M.; Bedoya, A.; Hartwig, M. G.; Davis, R. D.; Lopes, K. E.; Wegner, W. E.; Chen, D. F.; Palmer, S. M.

2015-01-01

As HLAs antibody detection technology has evolved, there is now detailed HLA antibody information available on prospective transplant recipients. Determining single antigen antibody specificity allows for a calculated panel reactive antibodies (cPRA) value, providing an estimate of the effective donor pool. For broadly sensitized lung transplant candidates (cPRA ≥ 80%), our center adopted a pretransplant multimodal desensitization protocol in an effort to decrease the cPRA and expand the donor pool. This desensitization protocol included plasmapheresis, solumedrol, bortezomib and rituximab given in combination over 19 days followed by intravenous immunoglobulin. Eight of 18 candidates completed therapy with the primary reasons for early discontinuation being transplant (by avoiding unacceptable antigens) or thrombocytopenia. In a mixed-model analysis, there were no significant changes in PRA or cPRA changes over time with the protocol. A sub-analysis of the median fluorescence intensity (MFI) change indicated a small decline that was significant in antibodies with MFI 5000–10 000. Nine of 18 candidates subsequently had a transplant. Posttransplant survival in these nine recipients was comparable to other pretransplant-sensitized recipients who did not receive therapy. In summary, an aggressive multi-modal desensitization protocol does not significantly reduce pretransplant HLA antibodies in a broadly sensitized lung transplant candidate cohort. PMID:24666831

Phage display-derived human antibodies in clinical development and therapy

PubMed Central

Frenzel, André; Schirrmann, Thomas; Hust, Michael

2016-01-01

ABSTRACT Over the last 3 decades, monoclonal antibodies have become the most important class of therapeutic biologicals on the market. Development of therapeutic antibodies was accelerated by recombinant DNA technologies, which allowed the humanization of murine monoclonal antibodies to make them more similar to those of the human body and suitable for a broad range of chronic diseases like cancer and autoimmune diseases. In the early 1990s in vitro antibody selection technologies were developed that enabled the discovery of “fully” human antibodies with potentially superior clinical efficacy and lowest immunogenicity. Antibody phage display is the first and most widely used of the in vitro selection technologies. It has proven to be a robust, versatile platform technology for the discovery of human antibodies and a powerful engineering tool to improve antibody properties. As of the beginning of 2016, 6 human antibodies discovered or further developed by phage display were approved for therapy. In 2002, adalimumab (Humira®) became the first phage display-derived antibody granted a marketing approval. Humira® was also the first approved human antibody, and it is currently the best-selling antibody drug on the market. Numerous phage display-derived antibodies are currently under advanced clinical investigation, and, despite the availability of other technologies such as human antibody-producing transgenic mice, phage display has not lost its importance for the discovery and engineering of therapeutic antibodies. Here, we provide a comprehensive overview about phage display-derived antibodies that are approved for therapy or in clinical development. A selection of these antibodies is described in more detail to demonstrate different aspects of the phage display technology and its development over the last 25 years. PMID:27416017

Personalizing therapies for gastric cancer: Molecular mechanisms and novel targeted therapies

PubMed Central

Luis, Michael; Tavares, Ana; Carvalho, Liliana S; Lara-Santos, Lúcio; Araújo, António; de Mello, Ramon Andrade

2013-01-01

Globally, gastric cancer is the 4th most frequently diagnosed cancer and the 2nd leading cause of death from cancer, with an estimated 990000 new cases and 738000 deaths registered in 2008. In the advanced setting, standard chemotherapies protocols acquired an important role since last decades in prolong survival. Moreover, recent advances in molecular therapies provided a new interesting weapon to treat advanced gastric cancer through anti-human epidermal growth factor receptor 2 (HER2) therapies. Trastuzumab, an anti-HER2 monoclonal antibody, was the first target drug in the metastatic setting that showed benefit in overall survival when in association with platinum-5-fluorouracil based chemotherapy. Further, HER2 overexpression analysis acquired a main role in predict response for trastuzumab in this field. Thus, we conducted a review that will discuss the main points concerning trastuzumab and HER2 in gastric cancer, providing a comprehensive overview of molecular mechanisms and novel trials involved. PMID:24151357

Dual display: phage selection driven by co-engagement of two targets by two different antibody fragments.

PubMed

Fagète, Séverine; Botas-Perez, Ledicia; Rossito-Borlat, Irène; Adea, Kenneth; Gueneau, Franck; Ravn, Ulla; Rousseau, François; Kosco-Vilbois, Marie; Fischer, Nicolas; Hartley, Oliver

2017-09-01

Antibody phage display technology has supported the emergence of numerous therapeutic antibodies. The development of bispecific antibodies, a promising new frontier in antibody therapy, could be facilitated by new phage display approaches that enable pairs of antibodies to be co-selected based on co-engagement of their respective targets. We describe such an approach, making use of two complementary leucine zipper domains that heterodimerize with high affinity. Phagemids encoding a first antibody fragment (scFv) fused to phage coat protein via the first leucine zipper are rescued in bacteria expressing a second scFv fused to the second leucine zipper as a soluble periplasmic protein, so that it is acquired by phage during assembly. Using a soluble scFv specific for a human CD3-derived peptide, we show that its acquisition by phage displaying an irrelevant antibody is sufficiently robust to drive selection of rare phage (1 in 105) over three rounds of panning. We then set up a model selection experiment using a cell line expressing the chemokine receptor CCR5 fused to the CD3 peptide together with a panel of phage clones capable displaying either an anti-CCR5 scFv or an irrelevant antibody, with or without the capacity to acquire the soluble anti-CD3 scFv. In this experiment we showed that rare phage (1 in 105) capable of displaying the two different scFvs can be specifically enriched over four rounds of panning. This approach has the potential to be applied to the identification of pairs of ligands capable of co-engaging two different user-defined targets, which would facilitate the discovery of novel bispecific antibodies. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

New Molecular Targets of Anticancer Therapy - Current Status and Perspectives.

PubMed

Zajac, Marianna; Muszalska, Izabela; Jelinska, Anna

2016-01-01

Molecularly targeted anticancer therapy involves the use of drugs or other substances affecting specific molecular targets that play a part in the development, progression and spread of a given neoplasm. By contrast, the majority of classical chemotherapeutics act on all rapidly proliferating cells, both healthy and cancerous ones. Target anticancer drugs are designed to achieve a particular aim and they usually act cytostatically, not cytotoxically like classical chemotherapeutics. At present, more than 300 biological molecular targets have been identified. The proteins involved in cellular metabolism include (among others) receptor proteins, signal transduction proteins, mRNA thread matrix synthesis proteins participating in neoplastic transformation, cell cycle control proteins, functional and structural proteins. The receptor proteins that are targeted by currently used anticancer drugs comprise the epithelial growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR) and vascular endothelial growth factor receptor(VEGFR). Target anticancer drugs may affect extracellular receptor domains (antibodies) or intracellular receptor domains (tyrosine kinase inhibitors). The blocking of the mRNA thread containing information about the structure of oncogenes (signal transduction proteins) is another molecular target of anticancer drugs. That type of treatment, referred to as antisense therapy, is in clinical trials. When the synthesis of genetic material is disturbed, in most cases the passage to the next cycle phase is blocked. The key proteins responsible for the blockage are cyclines and cycline- dependent kinases (CDK). Clinical trials are focused on natural and synthetic substances capable of blocking various CDKs. The paper discusses the molecular targets and chemical structure of target anticancer drugs that have been approved for and currently applied in antineoplastic therapy together with indications and contraindications for their

Interferon-targeted therapy in systemic lupus erythematosus: Is this an alternative to targeting B and T cells?

PubMed

Kalunian, K C

2016-09-01

Clinical trials of investigational agents in systemic lupus erythematosus (SLE) have focused on targeting dysregulated B and T cells; however, recent translational research findings of the importance of the dysregulation of the innate immune system in SLE have led to clinical trials that target interferon. Three biologics that target type I interferons have been tested for their efficacy and safety in active SLE patients; these phase II trials have tested the hypothesis that down-regulation of interferon-regulated gene expression (the interferon signature) lessen the clinical burden of SLE. Rontalizumab, an anti-interferon-α monoclonal antibody, was studied in patients who had discontinued immunosuppressants. This study failed to show efficacy as assessed by both two outcome assessments; however, in low interferon signature patients, response was higher and corticosteroid usage was less in rontalizumab-treated patients. Sifalimumab, another anti-interferon-α monoclonal antibody, was studied in patients who remained on standard of care therapy. This study showed significantly better efficacy in patients treated with two sifalimumab dosages; significant differences were seen in the high interferon signature group. In a similar design and in a similar population as the sifalimumab study, anifrolumab, a monoclonal antibody that binds to a type I interferon receptor, was studied in patients who remained on standard of care therapy. In this study, one dosage group demonstrated efficacy and statistically significant effects were achieved in both tested dosage groups with secondary end points. Oral corticosteroid reduction to ≤7.5 mg daily was achieved in one of the tested dosage groups and organ-specific outcomes were significantly improved in that same group. For all studies, no significant differences in serious adverse effects were seen; although, herpes zoster infections were increased in sifalimumab- and anifrolumab-treated patients and influenza rates were

Clinical Advancements in the Targeted Therapies against Liver Fibrosis

PubMed Central

Nagórniewicz, Beata; Prakash, Jai

2016-01-01

Hepatic fibrosis, characterized by excessive accumulation of extracellular matrix (ECM) proteins leading to liver dysfunction, is a growing cause of mortality worldwide. Hepatocellular damage owing to liver injury leads to the release of profibrotic factors from infiltrating inflammatory cells that results in the activation of hepatic stellate cells (HSCs). Upon activation, HSCs undergo characteristic morphological and functional changes and are transformed into proliferative and contractile ECM-producing myofibroblasts. Over recent years, a number of therapeutic strategies have been developed to inhibit hepatocyte apoptosis, inflammatory responses, and HSCs proliferation and activation. Preclinical studies have yielded numerous targets for the development of antifibrotic therapies, some of which have entered clinical trials and showed improved therapeutic efficacy and desirable safety profiles. Furthermore, advancements have been made in the development of noninvasive markers and techniques for the accurate disease assessment and therapy responses. Here, we focus on the clinical developments attained in the field of targeted antifibrotics for the treatment of liver fibrosis, for example, small molecule drugs, antibodies, and targeted drug conjugate. We further briefly highlight different noninvasive diagnostic technologies and will provide an overview about different therapeutic targets, clinical trials, endpoints, and translational efforts that have been made to halt or reverse the progression of liver fibrosis. PMID:27999454

Liver toxicity of chemotherapy and targeted therapy for breast cancer patients with hepatitis virus infection.

PubMed

Liu, Yu; Li, Zhan-Yi; Li, Xi; Wang, Jia-Ni; Huang, Qun-Ai; Huang, Yong

2017-10-01

Chemotherapy has greatly improved the prognosis of breast cancer patients. However, it may also result in undesirable side effects such as hepatitis virus reactivation. Little information is available on the liver toxicity of chemotherapy and targeted therapy for breast cancer patients with hepatitis virus (HBV/HCV) infection. We performed a retrospective survey of 835 patients diagnosed with breast cancer between January 2010 and December 2015 at our institution. All patients had been screened for HBV/HCV infection at the time of breast cancer diagnosis. We retrospectively investigated the toxicity of chemotherapy and the changes in HBV/HCV load based on a medical record review. 52 patients with positive anti-HBV antibody test and 21 patients with positive anti-HCV antibody tests received chemotherapy. 762 patients without HBV and HCV infection served as the control group. The morbidity of liver toxicity and disruptions in chemotherapy attributable to liver toxicity were not significantly different among control group, HBV group and HCV groups (27.7% vs 34.6% vs 42.9%, P = 0.189 and 5.0% vs 9.6% vs 9.5%, P = 0.173, respectively). No patients presented with HBV/HCV reactivation. Breast cancer patients with HCV can be treated with chemotherapy and targeted therapy with trastuzumab. Breast cancer patients with HBV who accept antiviral therapy can be treated with chemotherapy and targeted therapy with trastuzumab and patients can benefit from prophylactic antiviral therapy before chemotherapy. However, a multidisciplinary cooperation and closely monitoring liver function during the course of chemotherapy may benefit patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Surrogate target cells expressing surface anti-idiotype antibody for the clinical evaluation of an internalizing CD22-specific antibody.

PubMed

Leung, Shui-On; Gao, Kai; Wang, Guang Yu; Cheung, Benny Ka-Wa; Lee, Kwan-Yeung; Zhao, Qi; Cheung, Wing-Tai; Wang, Jun Zhi

2015-01-01

SM03, a chimeric antibody that targets the B-cell restricted antigen CD22, is currently being clinically evaluated for the treatment of lymphomas and other autoimmune diseases in China. SM03 binding to surface CD22 leads to rapid internalization, making the development of an appropriate cell-based bioassay for monitoring changes in SM03 bioactivities during production, purification, storage, and clinical trials difficult. We report herein the development of an anti-idiotype antibody against SM03. Apart from its being used as a surrogate antigen for monitoring SM03 binding affinities, the anti-idiotype antibody was engineered to express as fusion proteins on cell surfaces in a non-internalizing manner, and the engineered cells were used as novel "surrogate target cells" for SM03. SM03-induced complement-mediated cytotoxicity (CMC) against these "surrogate target cells" proved to be an effective bioassay for monitoring changes in Fc functions, including those resulting from minor structural modifications borne within the Fc-appended carbohydrates. The approach can be generally applied for antibodies that target rapidly internalizing or non-surface bound antigens. The combined use of the anti-idiotype antibody and the surrogate target cells could help evaluate clinical parameters associated with safety and efficacies, and possibly the mechanisms of action of SM03.

Improved decision making for prioritizing tumor targeting antibodies in human xenografts: Utility of fluorescence imaging to verify tumor target expression, antibody binding and optimization of dosage and application schedule.

PubMed

Dobosz, Michael; Haupt, Ute; Scheuer, Werner

2017-01-01

Preclinical efficacy studies of antibodies targeting a tumor-associated antigen are only justified when the expression of the relevant antigen has been demonstrated. Conventionally, antigen expression level is examined by immunohistochemistry of formalin-fixed paraffin-embedded tumor tissue section. This method represents the diagnostic "gold standard" for tumor target evaluation, but is affected by a number of factors, such as epitope masking and insufficient antigen retrieval. As a consequence, variances and discrepancies in histological staining results can occur, which may influence decision-making and therapeutic outcome. To overcome these problems, we have used different fluorescence-labeled therapeutic antibodies targeting human epidermal growth factor receptor (HER) family members and insulin-like growth factor-1 receptor (IGF1R) in combination with fluorescence imaging modalities to determine tumor antigen expression, drug-target interaction, and biodistribution and tumor saturation kinetics in non-small cell lung cancer xenografts. For this, whole-body fluorescence intensities of labeled antibodies, applied as a single compound or antibody mixture, were measured in Calu-1 and Calu-3 tumor-bearing mice, then ex vivo multispectral tumor tissue analysis at microscopic resolution was performed. With the aid of this simple and fast imaging method, we were able to analyze the tumor cell receptor status of HER1-3 and IGF1R, monitor the antibody-target interaction and evaluate the receptor binding sites of anti-HER2-targeting antibodies. Based on this, the most suitable tumor model, best therapeutic antibody, and optimal treatment dosage and application schedule was selected. Predictions drawn from obtained imaging data were in excellent concordance with outcome of conducted preclinical efficacy studies. Our results clearly demonstrate the great potential of combined in vivo and ex vivo fluorescence imaging for the preclinical development and characterization of

Erythrocyte membrane-coated gold nanocages for targeted photothermal and chemical cancer therapy

NASA Astrophysics Data System (ADS)

Zhu, Dao-Ming; Xie, Wei; Xiao, Yu-Sha; Suo, Meng; Zan, Ming-Hui; Liao, Qing-Quan; Hu, Xue-Jia; Chen, Li-Ben; Chen, Bei; Wu, Wen-Tao; Ji, Li-Wei; Huang, Hui-Ming; Guo, Shi-Shang; Zhao, Xing-Zhong; Liu, Quan-Yan; Liu, Wei

2018-02-01

Recently, red blood cell (RBC) membrane-coated nanoparticles have attracted much attention because of their excellent immune escapability; meanwhile, gold nanocages (AuNs) have been extensively used for cancer therapy due to their photothermal effect and drug delivery capability. The combination of the RBC membrane coating and AuNs may provide an effective approach for targeted cancer therapy. However, few reports have shown the utilization of combining these two technologies. Here, we design erythrocyte membrane-coated gold nanocages for targeted photothermal and chemical cancer therapy. First, anti-EpCam antibodies were used to modify the RBC membranes to target 4T1 cancer cells. Second, the antitumor drug paclitaxel (PTX) was encapsulated into AuNs. Then, the AuNs were coated with the modified RBC membranes. These new nanoparticles were termed EpCam-RPAuNs. We characterized the capability of the EpCam-RPAuNs for selective tumor targeting via exposure to near-infrared irradiation. The experimental results demonstrate that EpCam-RPAuNs can effectively generate hyperthermia and precisely deliver the antitumor drug PTX to targeted cells. We also validated the biocompatibility of the EpCam-RAuNs in vitro. By combining the molecularly modified targeting RBC membrane and AuNs, our approach provides a new way to design biomimetic nanoparticles to enhance the surface functionality of nanoparticles. We believe that EpCam-RPAuNs can be potentially applied for cancer diagnoses and therapies.

Ki-67 as a molecular target for therapy in an in vitro three-dimensional model for ovarian cancer.

PubMed

Rahmanzadeh, Ramtin; Rai, Prakash; Celli, Jonathan P; Rizvi, Imran; Baron-Lühr, Bettina; Gerdes, Johannes; Hasan, Tayyaba

2010-11-15

Targeting molecular markers and pathways implicated in cancer cell growth is a promising avenue for developing effective therapies. Although the Ki-67 protein (pKi-67) is a key marker associated with aggressively proliferating cancer cells and poor prognosis, its full potential as a therapeutic target has never before been successfully shown. In this regard, its nuclear localization presents a major hurdle because of the need for intracellular and intranuclear delivery of targeting and therapeutic moieties. Using a liposomally encapsulated construct, we show for the first time the specific delivery of a Ki-67-directed antibody and subsequent light-triggered death in the human ovarian cancer cell line OVCAR-5. Photoimmunoconjugate-encapsulating liposomes (PICEL) were constructed from anti-pKi-67 antibodies conjugated to fluorescein 5(6)-isothiocyanate, as a photoactivatable agent, followed by encapsulation in noncationic liposomes. Nucleolar localization of the PICELs was confirmed by confocal imaging. Photodynamic activation with PICELs specifically killed pKi-67-positive cancer cells both in monolayer and in three-dimensional (3D) cultures of OVCAR-5 cells, with the antibody TuBB-9 targeting a physiologically active form of pKi-67 but not with MIB-1, directed to a different epitope. This is the first demonstration of (a) the exploitation of Ki-67 as a molecular target for therapy and (b) specific delivery of an antibody to the nucleolus in monolayer cancer cells and in an in vitro 3D model system. In view of the ubiquity of pKi-67 in proliferating cells in cancer and the specificity of targeting in 3D multicellular acini, these findings are promising and the approach merits further investigation. Copyright © 2010 AACR.

Ki-67 as a molecular target for therapy in an in vitro 3D model for ovarian cancer

PubMed Central

Rahmanzadeh, Ramtin; Rai, Prakash; Celli, Jonathan P.; Rizvi, Imran; Baron-Lühr, Bettina; Gerdes, Johannes; Hasan, Tayyaba

2010-01-01

Targeting molecular markers and pathways implicated in cancer cell growth is a promising avenue for developing effective therapies. Although the Ki-67 protein (pKi-67) is a key marker associated with aggressively proliferating cancer cells and poor prognosis, its full potential as a therapeutic target has never before been successfully demonstrated. In this regard, its nuclear localization presents a major hurdle because of the need for intracellular and intranuclear delivery of targeting and therapeutic moieties. Using a liposomally encapsulated construct, we demonstrate for the first time, the specific delivery of a Ki-67 directed antibody and subsequent light-triggered death in a human ovarian cancer cell line OVCAR-5. Photoimmunoconjugate encapsulating liposomes (PICELs) were constructed from anti-pKi-67 antibodies conjugated to fluorescein isothiocyanate, as a photoactivatable agent followed by encapsulation in non-cationic liposomes. Nucleolar localization of the PICELs was confirmed by confocal imaging. Photodynamic activation with PICELs specifically killed pKi-67 positive cancer cells both in monolayer and in 3D cultures of OVCAR-5 cells with the antibody TuBB-9 targeting a physiologically active form of pKi-67 but not with MIB-1, directed to a different epitope. This is the first demonstration of: - 1. the exploitation of Ki-67 as a molecular target for therapy and - 2. specific delivery of an antibody to the nucleolus in monolayer cancer cells and in an in vitro 3D model system. In view of the ubiquity of pKi-67 in proliferating cells in cancer and the specificity of targeting in 3D multicellular acini, these findings are promising and the approach merits further investigation. PMID:21045152

Theranostic nanoparticles carrying doxorubicin attenuate targeting ligand specific antibody responses following systemic delivery.

PubMed

Yang, Emmy; Qian, Weiping; Cao, Zehong; Wang, Liya; Bozeman, Erica N; Ward, Christina; Yang, Bin; Selvaraj, Periasamy; Lipowska, Malgorzata; Wang, Y Andrew; Mao, Hui; Yang, Lily

2015-01-01

Understanding the effects of immune responses on targeted delivery of nanoparticles is important for clinical translations of new cancer imaging and therapeutic nanoparticles. In this study, we found that repeated administrations of magnetic iron oxide nanoparticles (IONPs) conjugated with mouse or human derived targeting ligands induced high levels of ligand specific antibody responses in normal and tumor bearing mice while injections of unconjugated mouse ligands were weakly immunogenic and induced a very low level of antibody response in mice. Mice that received intravenous injections of targeted and polyethylene glycol (PEG)-coated IONPs further increased the ligand specific antibody production due to differential uptake of PEG-coated nanoparticles by macrophages and dendritic cells. However, the production of ligand specific antibodies was markedly inhibited following systemic delivery of theranostic nanoparticles carrying a chemotherapy drug, doxorubicin. Targeted imaging and histological analysis revealed that lack of the ligand specific antibodies led to an increase in intratumoral delivery of targeted nanoparticles. Results of this study support the potential of further development of targeted theranostic nanoparticles for the treatment of human cancers.

Therapeutic targets and new directions for antibodies developed for ovarian cancer

PubMed Central

Bax, Heather J.; Josephs, Debra H.; Pellizzari, Giulia; Spicer, James F.; Montes, Ana; Karagiannis, Sophia N.

2016-01-01

ABSTRACT Antibody therapeutics against different target antigens are widely used in the treatment of different malignancies including ovarian carcinomas, but this disease still requires more effective agents. Improved understanding of the biological features, signaling pathways, and immunological escape mechanisms involved in ovarian cancer has emerged in the past few years. These advances, including an appreciation of the cross-talk between cancer cells and the patient's immune system, have led to the identification of new targets. In turn, potential antibody treatments with various mechanisms of action, including immune activation or toxin-delivery, that are directed at these targets have been developed. Here, we identify established as well as novel targets for antibodies in ovarian cancer, and discuss how they may provide fresh opportunities to identify interventions with enhanced therapeutic potential. PMID:27494775

Molecular targeted therapy for advanced gastric cancer.

PubMed

Kim, Jong Gwang

2013-03-01

Although medical treatment has been shown to improve quality of life and prolong survival, no significant progress has been made in the treatment of advanced gastric cancer (AGC) within the last two decades. Thus, the optimum standard first-line chemotherapy regimen for AGC remains debatable, and most responses to chemotherapy are partial and of short duration; the median survival is approximately 7 to 11 months, and survival at 2 years is exceptionally > 10%. Recently, remarkable progress in tumor biology has led to the development of new agents that target critical aspects of oncogenic pathways. For AGC, many molecular targeting agents have been evaluated in international randomized studies, and trastuzumab, an anti-HER-2 monoclonal antibody, has shown antitumor activity against HER-2-positive AGC. However, this benefit is limited to only ~20% of patients with AGC (patients with HER-2-positive AGC). Therefore, there remains a critical need for both the development of more effective agents and the identification of molecular predictive and prognostic markers to select those patients who will benefit most from specific chemotherapeutic regimens and targeted therapies.

Current therapies and targets for type 2 diabetes mellitus: a review.

PubMed

Chellapan, Dinesh K; Sheng Yap, Wei; Bt Ahmad Suhaimi, Nurfatihah A; Gupta, Gaurav; Dua, Kamal

2018-04-24

The prevalence of type 2 diabetes mellitus (T2DM) has been increasing at an alarming rate. With an increased understanding of the pathophysiology and pathogenesis of T2DM, various new therapeutic options have been developed to target different key defects in T2DM. Incremental innovations of existing therapies either through unprecedented drug combinations, modified drug molecules, or improved delivery systems are capable to nullify some of the undesirable side effects of traditional therapies as well as to enhance effectiveness. The existing administration routes include inhalation, nasal, buccal, parenteral and oral. Newer drug targets such as protein kinase B (Akt/PKB), AMPactivated protein kinase (AMPK), sirtuin (SIRT), and others are novel approaches that act via different mechanisms and possibly treating T2DM of distinct variations and aetiologies. Other therapies such as endobarrier, gene therapy, and stem cell technology utilize advanced techniques to treat T2DM, and the potential of these therapies are still being explored. Gene therapy is plausible to fix the underlying pathology of T2DM instead of using traditional reactive treatments, especially with the debut of Clustered Regularly Interspaced Short Palindromic RepeatsCRISPR associated protein9 (CRISPRCas9) gene editing tool. Molecular targets in T2DM are also being extensively studied as it could target the defects at the molecular level. Furthermore, antibody therapies and vaccinations are also being developed against T2DM; but the ongoing clinical trials are relatively lesser and the developmental progress is slower. Although, there are many therapies designed to cure T2DM, each of them has their own advantages and disadvantages. The preference for the treatment plan usually depends on the health status of the patient and the treatment goal. Therefore, an ideal treatment should take patient's compliance, efficacy, potency, bioavailability, and other pharmacological and nonpharmacological properties

Specific targeting and toxicity of sulphonated aluminium phthalocyanine photosensitised liposomes directed to cells by monoclonal antibody in vitro.

PubMed Central

Morgan, J.; Gray, A. G.; Huehns, E. R.

1989-01-01

A partially purified fraction of the water soluble photosensitive dye sulphonated aluminium phthalocyanine (AlSPc) was encapsulated in liposomes which were then linked to a targeting monoclonal antibody 791T/36 using a heterobifunctional linking agent. The photocytotoxic effects of the liposomes were determined on two cell lines bearing an antigen with which the targeting antibody binds: 791T, an osteosarcoma and C170, a colorectal carcinoma; and a control cell line not bearing the antigen; DW-BCL, an Epstein-Barr virus immortalised B-cell line. Antibody dependent cytotoxicity was observed in 791T and C170 cells and was proportional to the number of antigens on the cells, the AlSPc concentration and the time of exposure to activating red light. No significant toxicity was seen using untargeted liposomes, control cells or free AlSPc fraction under similar conditions. Targeted cells and controls kept in the dark also showed no significant toxicity. A possible mechanism of action is postulated and simple adaptations which demonstrate the versatility of the model are discussed. Some suggestions as to the clinical situations to which this system might be applied in the form of photodynamic therapy (PDT) are made. PMID:2930700

Nanoparticles for the delivery of therapeutic antibodies: Dogma or promising strategy?

PubMed

Sousa, Flávia; Castro, Pedro; Fonte, Pedro; Kennedy, Patrick J; Neves-Petersen, Maria Teresa; Sarmento, Bruno

2017-10-01

Over the past two decades, therapeutic antibodies have demonstrated promising results in the treatment of a wide array of diseases. However, the application of antibody-based therapy implies multiple administrations and a high cost of antibody production, resulting in costly therapy. Another disadvantage inherent to antibody-based therapy is the limited stability of antibodies and the low level of tissue penetration. The use of nanoparticles as delivery systems for antibodies allows for a reduction in antibody dosing and may represent a suitable alternative to increase antibody stability Areas covered: We discuss different nanocarriers intended for the delivery of antibodies as well as the corresponding encapsulation methods. Recent developments in antibody nanoencapsulation, particularly the possible toxicity issues that may arise from entrapment of antibodies into nanocarriers, are also assessed. In addition, this review will discuss the alterations in antibody structure and bioactivity that occur with nanoencapsulation. Expert opinion: Nanocarriers can protect antibodies from degradation, ensuring superior bioavailability. Encapsulation of therapeutic antibodies may offer some advantages, including potential targeting, reduced immunogenicity and controlled release. Furthermore, antibody nanoencapsulation may aid in the incorporation of the antibodies into the cells, if intracellular components (e.g. intracellular enzymes, oncogenic proteins, transcription factors) are to be targeted.

Novel strategy for a bispecific antibody: induction of dual target internalization and degradation.

PubMed

Lee, J M; Lee, S H; Hwang, J-W; Oh, S J; Kim, B; Jung, S; Shim, S-H; Lin, P W; Lee, S B; Cho, M-Y; Koh, Y J; Kim, S Y; Ahn, S; Lee, J; Kim, K-M; Cheong, K H; Choi, J; Kim, K-A

2016-08-25

Activation of the extensive cross-talk among the receptor tyrosine kinases (RTKs), particularly ErbB family-Met cross-talk, has emerged as a likely source of drug resistance. Notwithstanding brilliant successes were attained while using small-molecule inhibitors or antibody therapeutics against specific RTKs in multiple cancers over recent decades, a high recurrence rate remains unsolved in patients treated with these targeted inhibitors. It is well aligned with multifaceted properties of cancer and cross-talk and convergence of signaling pathways of RTKs. Thereby many therapeutic interventions have been actively developed to overcome inherent or acquired resistance. To date, no bispecific antibody (BsAb) showed complete depletion of dual RTKs from the plasma membrane and efficient dual degradation. In this manuscript, we report the first findings of a target-specific dual internalization and degradation of membrane RTKs induced by designed BsAbs based on the internalizing monoclonal antibodies and the therapeutic values of these BsAbs. Leveraging the anti-Met mAb able to internalize and degrade by a unique mechanism, we generated the BsAbs for Met/epidermal growth factor receptor (EGFR) and Met/HER2 to induce an efficient EGFR or HER2 internalization and degradation in the presence of Met that is frequently overexpressed in the invasive tumors and involved in the resistance against EGFR- or HER2-targeted therapies. We found that Met/EGFR BsAb ME22S induces dissociation of the Met-EGFR complex from Hsp90, followed by significant degradation of Met and EGFR. By employing patient-derived tumor models we demonstrate therapeutic potential of the BsAb-mediated dual degradation in various cancers.

Cardiotoxicity of novel HER2-targeted therapies.

PubMed

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

2013-08-01

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

Chimeric antigen receptor (CAR)-directed adoptive immunotherapy: a new era in targeted cancer therapy.

PubMed

Chen, Yamei; Liu, Delong

2014-01-01

As a result of the recent advances in molecular immunology, virology, genetics, and cell processing, chimeric antigen receptor (CAR)-directed cancer therapy has finally arrived for clinical application. CAR-directed adoptive immunotherapy represents a novel form of gene therapy, cellular therapy, and immunotherapy, a combination of three in one. Early phase clinical trial was reported in patients with refractory chronic lymphoid leukemia with 17p deletion. Accompanying the cytokine storm and tumor lysis syndrome was the shocking disappearance of the leukemia cells refractory to chemotherapy and monoclonal antibodies. CAR therapy was reproduced in both children and adults with refractory acute lymphoid leukemia. The CAR technology is being explored for solid tumor therapy, such as glioma. Close to 30 clinical trials are underway in the related fields (www.clinicaltrials.gov). Further improvement in gene targeting, cell expansion, delivery constructs (such as using Sleeping Beauty or Piggyback transposons) will undoubtedly enhance clinical utility. It is foreseeable that CAR-engineered T cell therapy will bring targeted cancer therapy into a new era.

Chimeric Monoclonal Antibody Cetuximab Targeting Epidermal Growth Factor-Receptor in Advanced Non-Melanoma Skin Cancer.

PubMed

Wollina, Uwe; Tchernev, Georgi; Lotti, Torello

2018-01-25

Non-melanoma skin cancer (NMSC) is the most common malignancy in humans. Targeted therapy with monoclonal antibody cetuximab is an option in case of advanced tumor or metastasis. We present and update of the use of cetuximab in NMSC searching PUBMED 2011-2017. The monoclonal antibody cetuximab against epidermal growth factor receptor (EGFR) has been investigated for its use in NMSC during the years 2011 to 2017 by a PUBMED research using the following items: "Non-melanoma skin cancer AND cetuximab," "cutaneous squamous cell carcinoma AND cetuximab," and "basal cell carcinoma AND cetuximab", and "cetuximab AND skin toxicity". Available data were analyzed including case reports. Current evidence of cetuximab efficacy in NMSC was mainly obtained in cutaneous SCC and to a lesser extend in BCC. Response rates vary for neoadjuvant, adjuvant, mono- and combined therapy with cetuximab. Management of cutaneous toxicities is necessary. Guidelines are available. Cetuximab is an option for recurrent or advanced NMSC of the skin. It seems to be justified particularly in very high-risk tumors. There is a need for phase III trials.

Fitness landscape of the human immunodeficiency virus envelope protein that is targeted by antibodies

PubMed Central

Louie, Raymond H. Y.; Kaczorowski, Kevin J.; Chakraborty, Arup K.; McKay, Matthew R.

2018-01-01

HIV is a highly mutable virus, and over 30 years after its discovery, a vaccine or cure is still not available. The isolation of broadly neutralizing antibodies (bnAbs) from HIV-infected patients has led to renewed hope for a prophylactic vaccine capable of combating the scourge of HIV. A major challenge is the design of immunogens and vaccination protocols that can elicit bnAbs that target regions of the virus’s spike proteins where the likelihood of mutational escape is low due to the high fitness cost of mutations. Related challenges include the choice of combinations of bnAbs for therapy. An accurate representation of viral fitness as a function of its protein sequences (a fitness landscape), with explicit accounting of the effects of coupling between mutations, could help address these challenges. We describe a computational approach that has allowed us to infer a fitness landscape for gp160, the HIV polyprotein that comprises the viral spike that is targeted by antibodies. We validate the inferred landscape through comparisons with experimental fitness measurements, and various other metrics. We show that an effective antibody that prevents immune escape must selectively bind to high escape cost residues that are surrounded by those where mutations incur a low fitness cost, motivating future applications of our landscape for immunogen design. PMID:29311326

Factors modulating the delivery and effect of enzymatic cargo conjugated with antibodies targeted to the pulmonary endothelium

PubMed Central

Shuvaev, Vladimir V.; Christofidou-Solomidou, Melpo; Scherpereel, Arnaud; Simone, Eric; Arguiri, Evguenia; Tliba, Samira; Pick, Jeremy; Kennel, Stephen; Albelda, Steven M.; Muzykantov, Vladimir R.

2007-01-01

Vascular drug targeting may improve therapies, yet a thorough understanding of the factors that regulate effects of drugs directed to the endothelium is needed to translate this approach into the clinical domain. To define factors modulating the efficacy and effects of endothelial targeting, we used a model enzyme (glucose oxidase, GOX) coupled with monoclonal antibodies (anti-TM34 or anti-TM201) to distinct epitopes of thrombomodulin, a surface determinant enriched in the pulmonary endothelium. GOX delivery results in conversion of glucose and oxygen into H2O2 leading to lung damage, a clear physiologic endpoint. Results of in vivo studies in mice showed that the efficiency of cargo delivery and its effect are influenced by a number of factors including: 1) The level of pulmonary uptake of the targeting antibody (anti-TM201 was more efficient than anti-TM34); 2) The amount of an active drug delivered to the target; 3) The amount of target antigen on the endothelium (animals with suppressed TM levels showed less targeting); and, 4) The substrate availability for the enzyme cargo in the target tissue (hyperoxia augmented GOX-induced injury). Therefore, both activity of the conjugates and biological factors control targeting and effects of enzymatic cargo. Understanding the nature of such “modulating biological factors” will hopefully allow optimization and ultimately applications of drug targeting for “individualized” pharmacotherapy. PMID:17270308

Cell Penetrating Bispecific Antibodies for Targeting Oncogenic Transcription Factors in Advanced Prostate Cancer

DTIC Science & Technology

2016-12-01

biochemical and biologic assay systems. The final specific aim was tol examine the ability of the bispecific antibody to perturb the growth of prostate ...designated by other documentation. TITLE: Cell-Penetrating Bispecific Antibodies for Targeting Oncogenic Transcription Factors in Advanced Prostate ...Bispecific Antibodies for Targeting Oncogenic Transcription Factors in Advanced Prostate Cancer Michael Lilly, MD Richard Weisbart, MD Medical

HIV therapy by a combination of broadly neutralizing antibodies in humanized mice.

PubMed

Klein, Florian; Halper-Stromberg, Ariel; Horwitz, Joshua A; Gruell, Henning; Scheid, Johannes F; Bournazos, Stylianos; Mouquet, Hugo; Spatz, Linda A; Diskin, Ron; Abadir, Alexander; Zang, Trinity; Dorner, Marcus; Billerbeck, Eva; Labitt, Rachael N; Gaebler, Christian; Marcovecchio, Paola; Incesu, Reha-Baris; Eisenreich, Thomas R; Bieniasz, Paul D; Seaman, Michael S; Bjorkman, Pamela J; Ravetch, Jeffrey V; Ploss, Alexander; Nussenzweig, Michel C

2012-12-06

Human antibodies to human immunodeficiency virus-1 (HIV-1) can neutralize a broad range of viral isolates in vitro and protect non-human primates against infection. Previous work showed that antibodies exert selective pressure on the virus but escape variants emerge within a short period of time. However, these experiments were performed before the recent discovery of more potent anti-HIV-1 antibodies and their improvement by structure-based design. Here we re-examine passive antibody transfer as a therapeutic modality in HIV-1-infected humanized mice. Although HIV-1 can escape from antibody monotherapy, combinations of broadly neutralizing antibodies can effectively control HIV-1 infection and suppress viral load to levels below detection. Moreover, in contrast to antiretroviral therapy, the longer half-life of antibodies led to control of viraemia for an average of 60 days after cessation of therapy. Thus, combinations of potent monoclonal antibodies can effectively control HIV-1 replication in humanized mice, and should be re-examined as a therapeutic modality in HIV-1-infected individuals.

Antibody Production in Response to Staphylococcal MS-1 Phage Cocktail in Patients Undergoing Phage Therapy.

PubMed

Żaczek, Maciej; Łusiak-Szelachowska, Marzanna; Jończyk-Matysiak, Ewa; Weber-Dąbrowska, Beata; Międzybrodzki, Ryszard; Owczarek, Barbara; Kopciuch, Agnieszka; Fortuna, Wojciech; Rogóż, Paweł; Górski, Andrzej

2016-01-01

In this study, we investigated the humoral immune response (through the release of IgG, IgA, and IgM antiphage antibodies) to a staphylococcal phage cocktail in patients undergoing experimental phage therapy at the Phage Therapy Unit, Medical Center of the Ludwik Hirszfeld Institute of Immunology and Experimental Therapy in Wrocław, Poland. We also evaluated whether occurring antiphage antibodies had neutralizing properties toward applied phages (K rate). Among 20 examined patients receiving the MS-1 phage cocktail orally and/or locally, the majority did not show a noticeably higher level of antiphage antibodies in their sera during phage administration. Even in those individual cases with an increased immune response, mostly by induction of IgG and IgM, the presence of antiphage antibodies did not translate into unsatisfactory clinical results of phage therapy. On the other hand, a negative outcome of the treatment occurred in some patients who showed relatively weak production of antiphage antibodies before and during treatment. This may imply that possible induction of antiphage antibodies is not an obstacle to the implementation of phage therapy and support our assumption that the outcome of the phage treatment does not primarily depend on the appearance of antiphage antibodies in sera of patients during therapy. These conclusions are in line with our previous findings. The confirmation of this thesis is of great interest as regards the efficacy of phage therapy in humans.

[Anti-FGF23 antibody therapy for patients with tumor-induced osteomalacia].

PubMed

Kinoshita, Yuka; Fukumoto, Seiji

2014-08-01

Tumor-induced osteomalacia (TIO) is a disease caused by fibroblast growth factor 23 (FGF23) secreted from the causative tumor. This disease is cured by complete surgical removal of the tumor. However, there are several difficult cases in which the responsible tumors cannot be found, are incompletely removed, or relapse after the surgery. Anti-FGF23 antibody is being studied as a novel therapy for FGF23-related hypophosphatemic diseases. The efficacy of anti-FGF23 antibodies were confirmed using a murine model of X-linked hypophosphatemic rickets (XLHR) , which is the most common heritable form of FGF23-related hypophosphatemic disease. In addition, results of phase I study of single injection of humanized anti-FGF23 antibody for adult patients with XLHR were recently published and the safety and effectiveness of this antibody was shown. This antibody therapy may be useful for patients with TIO with similar pathogenesis to that of XLHR.

A dual chain chimeric antigen receptor (CAR) in the native antibody format for targeting immune cells towards cancer cells without the need of an scFv.

PubMed

Faitschuk, E; Nagy, V; Hombach, A A; Abken, H

2016-10-01

Adoptive cell therapy with chimeric antigen receptor (CAR)-modified T cells showed remarkable therapeutic efficacy in the treatment of leukaemia/lymphoma. However, the application to a variety of cancer entities is often constricted by the non-availability of a single chain antibody (scFv), which is usually the targeting domain in a CAR, while antibodies in the natural format are often available. To overcome the limitation, we designed a CAR that uses an antibody in its natural configuration for binding. Such CAR consists of two chains, the immunoglobulin light and heavy chain with their constant regions, whereby the heavy chain is anchored to the membrane and linked to an intracellular signalling domain for T-cell activation. The two chains form a stable heterodimer, a so-called dual chain CAR (dcCAR), and bind with high affinity and in a specific manner to their cognate antigen. By specific binding, the dcCAR activates engineered T cells for the release of pro-inflammatory cytokines and for target cell lysis. We provide evidence by three examples that the dcCAR format is universally applicable and thereby broadens the CAR cell therapy towards a larger variety of targets for which an scFv antibody is not available.

Targeting CD147 for T to NK Lineage Reprogramming and Tumor Therapy.

PubMed

Geng, Jie-Jie; Tang, Juan; Yang, Xiang-Min; Chen, Ruo; Zhang, Yang; Zhang, Kui; Miao, Jin-Lin; Chen, Zhi-Nan; Zhu, Ping

2017-06-01

CD147 is highly expressed on the surface of numerous tumor cells to promote invasion and metastasis. Targeting these cells with CD147-specific antibodies has been validated as an effective approach for lung and liver cancer therapy. In the immune system, CD147 is recognized as a co-stimulatory receptor and impacts the outcome of thymic selection. Using T cell-specific deletion, we showed here that in thymus CD147 is indispensable for the stable αβ T cell lineage commitment: loss of CD147 biases both multipotent DN (double negative) and fully committed DP (double positive) cells into innate NK-like lineages. Mechanistically, CD147 deficiency results in impaired Wnt signaling and expression of BCL11b, a master transcription factor in determining T cell identity. In addition, functional blocking of CD147 by antibody phenocopies genetic deletion to enrich NK-like cells in the periphery. Furthermore, using a melanoma model and orthotopic liver cancer transplants, we showed that the augmentation of NK-like cells strongly associates with resistance against tumor growth upon CD147 suppression. Therefore, besides its original function in tumorigenesis, CD147 is also an effective surface target for immune modulation in tumor therapy. Copyright © 2017. Published by Elsevier B.V.

Current Molecular Targeted Therapy in Advanced Gastric Cancer: A Comprehensive Review of Therapeutic Mechanism, Clinical Trials, and Practical Application

PubMed Central

Li, Kaichun; Li, Jin

2016-01-01

Despite the great progress in the treatment of gastric cancer, it is still the third leading cause of cancer death worldwide. Patients often miss the opportunity for a surgical cure, because the cancer has already developed into advanced cancer when identified. Compared to best supportive care, chemotherapy can improve quality of life and prolong survival time, but the overall survival is often short. Due to the molecular study of gastric cancer, new molecular targeted drugs have entered the clinical use. Trastuzumab, an antibody targeting human epidermal growth factor receptor 2 (HER2), can significantly improve survival in advanced gastric cancer patients with HER2 overexpression. Second-line treatment of advanced gastric cancer with ramucirumab, an antibody targeting VEGFR-2, alone or in combination with paclitaxel, has been proved to provide a beneficial effect. The VEGFR-2 tyrosine kinase inhibitor, apatinib, can improve the survival of advanced gastric cancer patients after second-line chemotherapy failure. Unfortunately, none of the EGFR targeting antibodies (cetuximab or panitumumab), VEGF targeting monoclonal antibodies (bevacizumab), mTOR inhibitor (everolimus), or HGF/MET pathway targeting drugs has a significant survival benefit. Many other clinical trials based on molecular markers are underway. This review will summarize targeted therapies for advanced gastric cancer. PMID:26880889

Monoclonal antibodies as cancer therapeutics.

PubMed

Elloumi, Jihene; Jellali, Karim; Jemel, Ikram; Aifa, Sami

2012-04-01

Three main targets were subjected for the most approved monoclonal antibodies (mAbs) in cancer therapy: EGFR in solid cancer, the clusters of differentiation in blood cancer and VEGF in angiogenesis. Meanwhile side effects, the elevated costs and resistance problems are limiting the efficiency of mAbs as targeted therapy. The combinatory therapy with chemo or radiotherapy has improved the efficiency of mAbs. The present review aims to shed more light on the immunotherapy and the related patents that were developed for cancer treatment.

Carbamylated albumin is one of the target antigens of anti-carbamylated protein antibodies.

PubMed

Nakabo, Shuichiro; Hashimoto, Motomu; Ito, Shinji; Furu, Moritoshi; Ito, Hiromu; Fujii, Takao; Yoshifuji, Hajime; Imura, Yoshitaka; Nakashima, Ran; Murakami, Kosaku; Kuramoto, Nobuo; Tanaka, Masao; Satoh, Junko; Ishigami, Akihito; Morita, Satoshi; Mimori, Tsuneyo; Ohmura, Koichiro

2017-07-01

Anti-carbamylated protein (anti-CarP) antibodies are detected in RA patients. Fetal calf serum is used as an antigen source in anti-CarP ELISA, and the precise target antigens have not been found. We aimed to identify the target antigens of anti-CarP antibodies. Western blotting of anti-CarP antibodies was conducted. Anti-carbamylated human albumin (CarALB) antibody was detected by in-house ELISA for 493 RA patients and 144 healthy controls (HCs). An inhibition ELISA of anti-CarP antibodies by CarALB and citrullinated albumin (citALB) was performed using eight RA patients' sera. Serum CarALB was detected by liquid chromatography-tandem mass spectroscopy (LC/MS/MS), and the serum MPO concentration was measured by ELISA. We focused on carbamylated albumin because it corresponded to the size of the thickest band detected by western blotting of anti-CarP antibodies. Anti-CarALB antibody was detected in 31.4% of RA patients, and the correlation of the titres between anti-CarALB and anti-CarP was much closer than that between anti-citALB and anti-CCP antibodies (ρ = 0.59 and ρ = 0.16, respectively). The inhibition ELISA showed that anti-CarP antibodies were inhibited by CarALB, but not by citALB. CarALB was detected in sera from RA patients by LC/MS/MS. The serum MPO concentration was correlated with disease activity and was higher in RA patients with anti-CarALB antibody than in those without. We found that carbamylated albumin is a novel target antigen of anti-CarP antibodies, and it is the first reported target antigen that has not been reported as the target of ACPA. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Factors determining antibody distribution in tumors.

PubMed

Thurber, Greg M; Schmidt, Michael M; Wittrup, K Dane

2008-02-01

The development of antibody therapies for cancer is increasing rapidly, primarily owing to their specificity. Antibody distribution in tumors is often extremely uneven, however, leading to some malignant cells being exposed to saturating concentrations of antibody, whereas others are completely untargeted. This is detrimental because large regions of cells escape therapy, whereas other regions might be exposed to suboptimal concentrations that promote a selection of resistant mutants. The distribution of antibody depends on a variety of factors, including dose, affinity, antigens per cell and molecular size. Because these parameters are often known or easily estimated, a quick calculation based on simple modeling considerations can predict the uniformity of targeting within a tumor. Such analyses should enable experimental researchers to identify in a straightforward way the limitations in achieving evenly distributed antibody, and design and test improved antibody therapeutics more rationally.

Factors determining antibody distribution in tumors

PubMed Central

Thurber, Greg M.; Schmidt, Michael M.; Wittrup, K. Dane

2009-01-01

The development of antibody therapies for cancer is increasing rapidly, primarily owing to their specificity. Antibody distribution in tumors is often extremely uneven, however, leading to some malignant cells being exposed to saturating concentrations of antibody, whereas others are completely untargeted. This is detrimental because large regions of cells escape therapy, whereas other regions might be exposed to suboptimal concentrations that promote a selection of resistant mutants. The distribution of antibody depends on a variety of factors, including dose, affinity, antigens per cell and molecular size. Because these parameters are often known or easily estimated, a quick calculation based on simple modeling considerations can predict the uniformity of targeting within a tumor. Such analyses should enable experimental researchers to identify in a straightforward way the limitations in achieving evenly distributed antibody, and design and test improved antibody therapeutics more rationally. PMID:18179828

Antibody Engineering and Therapeutics

PubMed Central

Almagro, Juan Carlos; Gilliland, Gary L; Breden, Felix; Scott, Jamie K; Sok, Devin; Pauthner, Matthias; Reichert, Janice M; Helguera, Gustavo; Andrabi, Raiees; Mabry, Robert; Bléry, Mathieu; Voss, James E; Laurén, Juha; Abuqayyas, Lubna; Barghorn, Stefan; Ben-Jacob, Eshel; Crowe, James E; Huston, James S; Johnston, Stephen Albert; Krauland, Eric; Lund-Johansen, Fridtjof; Marasco, Wayne A; Parren, Paul WHI; Xu, Kai Y

2014-01-01

The 24th Antibody Engineering & Therapeutics meeting brought together a broad range of participants who were updated on the latest advances in antibody research and development. Organized by IBC Life Sciences, the gathering is the annual meeting of The Antibody Society, which serves as the scientific sponsor. Preconference workshops on 3D modeling and delineation of clonal lineages were featured, and the conference included sessions on a wide variety of topics relevant to researchers, including systems biology; antibody deep sequencing and repertoires; the effects of antibody gene variation and usage on antibody response; directed evolution; knowledge-based design; antibodies in a complex environment; polyreactive antibodies and polyspecificity; the interface between antibody therapy and cellular immunity in cancer; antibodies in cardiometabolic medicine; antibody pharmacokinetics, distribution and off-target toxicity; optimizing antibody formats for immunotherapy; polyclonals, oligoclonals and bispecifics; antibody discovery platforms; and antibody-drug conjugates. PMID:24589717

Thyroid-stimulation hormone-receptor antibodies as a predictor of thyrosuppressive drug therapy outcome in Graves' disease patients.

PubMed

Aleksić, Aleksandar Z; Aleksić, Željka; Manić, Saška; Mitov, Vladimir; Jolić, Aleksandar

2014-01-01

Graves' disease is autoimmune hyperthyroidism caused by pathological stimulation of thyroid-stimulation hormone-receptor antibodies. The decision on changing the therapy can be made on time by determining the prognostic factors of thyrosuppressive drug therapy outcome. The aim of the study was to determine the significance of thyroid-stimulation hormone-receptor antibodies level on the prediction of therapy outcome. The study was prospective and involved 106 drug-treated patients with newly diagnosed Graves' disease. Thyroid-stimulation hormone-receptor antibodies level was measured at the beginning of therapy, during therapy and 12 months after it had been introduced. No statistically significant difference in the level of thyroid-stimulation hormone-receptor antibodies was found at the beginning of disease and 12 months after the introduction of thyrosuppressive drug therapy among the patients who had been in remission and those who had not. Regardless of the outcome, thyroid-stimulation hormone-receptor antibodies level significantly decreased in all patients 12 months after the therapy had been introduced. The level of thyroid-stimulation hormone-receptor antibodies at the beginning of disease and 12 months after the introduction of therapy cannot predict the outcome of thyrosuppressive drug therapy.

[Targeted therapy: toward a clean and effective war against cancer].

PubMed

Castronovo, V; Waltregny, D; Detry, O; Coimbra Marques, C; De Roover, A; Honoré, P; De Pauw, E; Turtoi, A

2009-01-01

One promising avenue towards the development of more selective, better anticancer drugs consists in the targeted delivery of bioactive compounds to the tumor environment by means of binding molecules specific for tumor-associated biomarkers. Eligibility of such markers for therapeutic use implies ideally three criteria : (i) accessibility from the bloodstream, (ii) expression at sufficient level and (iii) no (or much lower) expression in normal tissues. Most current discovery strategies (such as biomarker searching into body fluids) provide no clue as to whether proteins of interest are accessible, in human tissues, to suitable high-affinity ligands, such as systemically delivered monoclonal antibodies. Innovative proteomic technologies are able to identify such accessible biomarkers and represent a key step in the clinical development of such target therapies.

Structural biology of antibody recognition of carbohydrate epitopes and potential uses for targeted cancer immunotherapies.

PubMed

Dingjan, Tamir; Spendlove, Ian; Durrant, Lindy G; Scott, Andrew M; Yuriev, Elizabeth; Ramsland, Paul A

2015-10-01

Monoclonal antibodies represent the most successful class of biopharmaceuticals for the treatment of cancer. Mechanisms of action of therapeutic antibodies are very diverse and reflect their ability to engage in antibody-dependent effector mechanisms, internalize to deliver cytotoxic payloads, and display direct effects on cells by lysis or by modulating the biological pathways of their target antigens. Importantly, one of the universal changes in cancer is glycosylation and carbohydrate-binding antibodies can be produced to selectively recognize tumor cells over normal tissues. A promising group of cell surface antibody targets consists of carbohydrates presented as glycolipids or glycoproteins. In this review, we outline the basic principles of antibody-based targeting of carbohydrate antigens in cancer. We also present a detailed structural view of antibody recognition and the conformational properties of a series of related tissue-blood group (Lewis) carbohydrates that are being pursued as potential targets of cancer immunotherapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Monoclonal antibodies targeting non-small cell lung cancer stem-like cells by multipotent cancer stem cell monoclonal antibody library.

PubMed

Cao, Kaiyue; Pan, Yunzhi; Yu, Long; Shu, Xiong; Yang, Jing; Sun, Linxin; Sun, Lichao; Yang, Zhihua; Ran, Yuliang

2017-02-01

Cancer stem cells (CSCs) are a rare subset of cancer cells that play a significant role in cancer initiation, spreading, and recurrence. In this study, a subpopulation of lung cancer stem-like cells (LCSLCs) was identified from non-small cell lung carcinoma cell lines, SPCA-1 and A549, using serum-free suspension sphere-forming culture method. A monoclonal antibody library was constructed using immunized BLAB/c mice with the multipotent CSC cell line T3A-A3. Flow cytometry analysis showed that 33 mAbs targeted antigens can be enriched in sphere cells compared with the parental cells of SPCA-1 and A549 cell lines. Then, we performed functional antibody screening including sphere-forming inhibiting and invasion inhibiting assay. The results showed that two antibodies, 12C7 and 9B8, notably suppressed the self-renewal and invasion of LCSLCs. Fluorescence-activated cell sorting (FACs) found that the positive cells recognized by mAbs, 12C7 or 9B8, displayed features of LCSLCs. Interestingly, we found that these two antibodies recognized different subsets of cells and their combination effect was superior to the individual effect both in vitro and in vivo. Tissue microarrays were applied to detect the expression of the antigens targeted by these two antibodies. The positive expression of 12C7 and 9B8 targeted antigen was 84.4 and 82.5%, respectively, which was significantly higher than that in the non-tumor lung tissues. In conclusion, we screened two potential therapeutic antibodies that target different subsets of LCSLCs.

C4d-negative antibody-mediated rejection with high anti-angiotensin II type I receptor antibodies in absence of donor-specific antibodies.

PubMed

Fuss, Alexander; Hope, Christopher M; Deayton, Susan; Bennett, Greg Donald; Holdsworth, Rhonda; Carroll, Robert P; Coates, P Toby H

2015-07-01

Acute antibody-mediated rejection can occur in absence of circulating donor-specific antibodies. Agonistic antibodies targeting the anti-angiotensin II type 1 receptor (anti-AT1 R) are emerging as important non-human leucocyte antigen (HLA) antibodies. Elevated levels of anti-angiotensin II receptor antibodies were first observed in kidney transplant recipients with malignant hypertension and allograft rejection. They have now been studied in three separate kidney transplant populations and associate to frequency of rejection, severity of rejection and graft failure. We report 11 cases of biopsy-proven, Complement 4 fragment d (C4d)-negative, acute rejection occurring without circulating donor-specific anti-HLA antibodies. In eight cases, anti-angiotensin receptor antibodies were retrospectively examined. The remaining three subjects were identified from our centre's newly instituted routine anti-angiotensin receptor antibody screening. All subjects fulfilled Banff 2013 criteria for antibody-mediated rejection and all responded to anti-rejection therapy, which included plasma exchange and angiotensin receptor blocker therapy. These cases support the routine assessment of anti-AT1 R antibodies in kidney transplant recipients to identify subjects at risk. Further studies will need to determine optimal assessment protocol and the effectiveness of pre-emptive treatment with angiotensin receptor blockers. © 2015 Asian Pacific Society of Nephrology.

Glycosylated Triterpenoids as Endosomal Escape Enhancers in Targeted Tumor Therapies

PubMed Central

Fuchs, Hendrik; Niesler, Nicole; Trautner, Alexandra; Sama, Simko; Jerz, Gerold; Panjideh, Hossein; Weng, Alexander

2017-01-01

Protein-based targeted toxins play an increasingly important role in targeted tumor therapies. In spite of their high intrinsic toxicity, their efficacy in animal models is low. A major reason for this is the limited entry of the toxin into the cytosol of the target cell, which is required to mediate the fatal effect. Target receptor bound and internalized toxins are mostly either recycled back to the cell surface or lysosomally degraded. This might explain why no antibody-targeted protein toxin has been approved for tumor therapeutic applications by the authorities to date although more than 500 targeted toxins have been developed within the last decades. To overcome the problem of insufficient endosomal escape, a number of strategies that make use of diverse chemicals, cell-penetrating or fusogenic peptides, and light-induced techniques were designed to weaken the membrane integrity of endosomes. This review focuses on glycosylated triterpenoids as endosomal escape enhancers and throws light on their structure, the mechanism of action, and on their efficacy in cell culture and animal models. Obstacles, challenges, opportunities, and future prospects are discussed. PMID:28536357

BRCAA1 antibody- and Her2 antibody-conjugated amphiphilic polymer engineered CdSe/ZnS quantum dots for targeted imaging of gastric cancer

NASA Astrophysics Data System (ADS)

Li, Chao; Ji, Yang; Wang, Can; Liang, Shujing; Pan, Fei; Zhang, Chunlei; Chen, Feng; Fu, Hualin; Wang, Kan; Cui, Daxiang

2014-05-01

Successful development of safe and highly effective nanoprobes for targeted imaging of in vivo early gastric cancer is a great challenge. Herein, we choose the CdSe/ZnS (core-shell) quantum dots (QDs) as prototypical materials, synthesized one kind of a new amphiphilic polymer including dentate-like alkyl chains and multiple carboxyl groups, and then used the prepared amphiphilic polymer to modify QDs. The resultant amphiphilic polymer engineered QDs (PQDs) were conjugated with BRCAA1 and Her2 monoclonal antibody, and prepared BRCAA1 antibody- and Her2 antibody-conjugated QDs were used for in vitro MGC803 cell labeling and in vivo targeted imaging of gastric cancer cells. Results showed that the PQDs exhibited good water solubility, strong photoluminescence (PL) intensity, and good biocompatibility. BRCAA1 antibody- and Her2 antibody-conjugated QD nanoprobes successfully realized targeted imaging of in vivo gastric cancer MGC803 cells. In conclusion, BRCAA1 antibody- and Her2 antibody-conjugated PQDs have great potential in applications such as single cell labeling and in vivo tracking, and targeted imaging and therapeutic effects' evaluation of in vivo early gastric cancer cells in the near future.

Proteomic Identification of Non-Gal Antibody Targets After Pig-to-Primate Cardiac Xenotransplantation

PubMed Central

Byrne, Guerard W.; Stalboerger, Paul G.; Davila, Eduardo; Heppelmann, Carrie J.; Gazi, Mozammel H.; McGregor, Hugh C. J.; LaBreche, Peter T.; Davies, William R.; Rao, Vinay P.; Oi, Keiji; Tazelaar, Henry D.; Logan, John S.; McGregor, Christopher G. A.

2008-01-01

Background Experience with non-antigenic galactose α1,3 galactose (αGal) polymers and development of αGal deficient pigs has reduced or eliminated the significance of this antigen in xenograft rejection. Despite these advances, delayed xenograft rejection (DXR) continues to occur most likely due to antibody responses to non-Gal endothelial cell (EC) antigens. Methods To gauge the diversity of the non-Gal antibody response we used antibody derived from CD46 transgenic heterotopic cardiac xenografts performed without T-cell immunosuppression, Group A (n = 4) and Gal knockout (GT-KO) heart transplants under tacrolimus and sirolimus immunosuppression, Group B (n = 8). Non-Gal antibody was measured by flow cytometry and by Western blots using GT-KO EC membrane antigens. A nanoLC/MS/MS analysis of proteins recovered from 2D gels was used to identify target antigens. Results Group A recipients exhibited a mixed cellular and humoral rejection. Group B recipients mainly exhibited classical DXR. Western blot analysis showed a non-Gal antibody response induced by GT+ and GT-KO hearts to an overlapping set of pig aortic EC membrane antigens. Proteomic analysis identified 14 potential target antigens but failed to define several immunodominant targets. Conclusions These experiments indicate that the non-Gal antibody response is directed to a number of stress response and inflammation related pig EC antigens and a few undefined targets. Further analysis of these antibody specificities using alternative methods is required to more fully define the repertoire of non-Gal antibody responses. PMID:18957049

Therapeutic antibodies: market considerations, disease targets and bioprocessing.

PubMed

Elvin, John G; Couston, Ruairidh G; van der Walle, Christopher F

2013-01-02

Antibodies are well established in mainstream clinical practice and present an exciting area for collaborative research and development in industry and academia alike. In this review, we will provide an overview of the current market and an outlook to 2015, focussing on whole antibody molecules while acknowledging the next generation scaffolds containing variable fragments. The market will be discussed in the context of disease targets, particularly in the areas of oncology and immune disorders which generate the greatest revenue by a wide margin. Emerging targets include central nervous system disorders which will also stimulate new delivery strategies. It is becoming increasingly apparent that a better understanding of bioprocessing is required in order to optimize the steps involved in the preparation of a protein prior to formulation. The latter is outside the scope of this review and nor is it our intention to discuss protein delivery and pharmacokinetics. The challenges that lie ahead include the discovery of new disease targets and the development of robust bioprocessing operations. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Clearance mechanism of a mannosylated antibody-enzyme fusion protein used in experimental cancer therapy.

PubMed

Kogelberg, Heide; Tolner, Berend; Sharma, Surinder K; Lowdell, Mark W; Qureshi, Uzma; Robson, Mathew; Hillyer, Tim; Pedley, R Barbara; Vervecken, Wouter; Contreras, Roland; Begent, Richard H J; Chester, Kerry A

2007-01-01

MFECP1 is a mannosylated antibody-enzyme fusion protein used in antibody-directed enzyme prodrug therapy (ADEPT). The antibody selectively targets tumor cells and the targeted enzyme converts a prodrug into a toxic drug. MFECP1 is obtained from expression in the yeast Pichia pastoris and produced to clinical grade. The P. pastoris-derived mannosylation of the fusion protein aids rapid normal tissue clearance required for successful ADEPT. The work presented provides evidence that MFECP1 is cleared by the endocytic and phagocytic mannose receptor (MR), which is known to bind to mannose-terminating glycans. MR-transfected fibroblast cells internalize MFECP1 as revealed by flow cytometry and confocal microscopy. Immunofluorescence microscopy shows that in vivo clearance in mice occurs predominantly by MR on liver sinusoidal endothelial cells, although MR is also expressed on adjacent Kupffer cells. In the spleen, MFECP1 is taken up by MR-expressing macrophages residing in the red pulp and not by dendritic cells which are found in the marginal zone and white pulp. Clearance can be inhibited in vivo by the MR inhibitor mannan as shown by increased enzyme activities in blood. The work improves understanding of interactions of MFECP1 with normal tissue, shows that glycosylation can be exploited in the design of recombinant anticancer therapeutics and opens the ways for optimizing pharmacokinetics of mannosylated recombinant therapeutics.

[Design of next generation antibody drug conjugates].

PubMed

Zhu, Gui-Dong; Fu, Yang-Xin

2013-07-01

Chemotherapy remains one of the major tools, along with surgery, radiotherapy, and more recently targeted therapy, in the war against cancer. There have appeared a plethora of highly potent cytotoxic drugs but the poor discriminability between cancerous and healthy cells of these agents limits their broader application in clinical settings. Therapeutic antibodies have emerged as an important class of biological anticancer agents, thanks to their ability in specific binding to tumor-associated antigens. While this important class of biologics can be used as single agents for the treatment of cancer through antibody-dependent cell cytotoxicity (ADCC), their therapeutical efficacy is often limited. Antitumor antibody drug conjugates (ADCs) combine the target-specificity of monoclonal antibody (mAb) and the highly active cell-killing drugs, taking advantages of the best characteristics out of both components. Thus, insufficiency of most naked mAbs in cancer therapy has been circumvented by arming the immunoglobulin with cytotoxic drugs. Here mAbs are used as vehicles to transport potent payloads to tumor cells. ADCs contain three main components: antibody, linker and cytotoxics (also frequently referred as payload). Antibodies can recognize and specifically bind to the tumor-specific antigens, leading to an antibody-assisted internalization, and payload release. While ADC has demonstrated tremendous success, a number of practical challenges limit the broader applications of this new class of anticancer therapy, including inefficient cellular uptake, low cytotoxicity, and off-target effects. This review article aims to cover recent advances in optimizing linkers with increased stability in circulation while allowing efficient payload release within tumor cells. We also attempt to provide some practical strategies in resolving the current challenges in this attractive research area, particularly to those new to the field.

Prostate-specific membrane antigen as a target for cancer imaging and therapy

PubMed Central

KIESS, A. P.; BANERJEE, S. R.; MEASE, R. C.; ROWE, S. P.; RAO, A.; FOSS, C. A.; CHEN, Y.; YANG, X.; CHO, S. Y.; NIMMAGADDA, S.; POMPER, M. G.

2016-01-01

The prostate-specific membrane antigen (PSMA) is a molecular target whose use has resulted in some of the most productive work toward imaging and treating prostate cancer over the past two decades. A wide variety of imaging agents extending from intact antibodies to low-molecular-weight compounds permeate the literature. In parallel there is a rapidly expanding pool of antibody-drug conjugates, radiopharmaceutical therapeutics, small-molecule drug conjugates, theranostics and nanomedicines targeting PSMA. Such productivity is motivated by the abundant expression of PSMA on the surface of prostate cancer cells and within the neovasculature of other solid tumors, with limited expression in most normal tissues. Animating the field is a variety of small-molecule scaffolds upon which the radionuclides, drugs, MR-detectable species and nanoparticles can be placed with relative ease. Among those, the urea-based agents have been most extensively leveraged, with expanding clinical use for detection and more recently for radiopharmaceutical therapy of prostate cancer, with surprisingly little toxicity. PSMA imaging of other cancers is also appearing in the clinical literature, and may overtake FDG for certain indications. Targeting PSMA may provide a viable alternative or first-line approach to managing prostate and other cancers. PMID:26213140

Immunologic advances in monoclonal antibody therapy: implications for oncology nursing.

PubMed

Karius, D; Marriott, M A

1997-04-01

To provide an overview of monoclonal antibody (MoAb) formation, therapeutic and diagnostic uses of MoAbs, and the implications for oncology nurses. Books and Journal articles (including research studies). Clinical trials have demonstrated the diagnostic and therapeutic potential of MoAb therapy. Advances in hybridoma technology and gene-splicing techniques have led to the formation of chimeric MoAbs, which exhibit decreased immunogenicity in the recipient. Clinical limitations with MoAb therapy include cross-reactivity with normal tissues, heterogeneity of antigen expression, presence of circulating antigen, antigenic modulation, tumor size and vascularity, and the anti-antibody response. MoAbs currently are used for diagnostic purposes and in phase I, II, and III clinical trials for cancer treatment. As research progresses, MoAbs are likely to be incorporated into the mainstream of cancer therapy as have other biologic response modifiers. Current uses of MoAb therapy in clinical trials involve nurses in many roles, including clinical nurse specialist, staff nurse, and research nurse. As more oncology nurses encounter MoAb therapy in practice, they will have to have an increased understanding of basic immunologic principles and the expertise to manage the unique toxicities associated with MoAb therapy.

Cutaneous Adverse Events of Targeted Therapies for Hematolymphoid Malignancies.

PubMed

Ransohoff, Julia D; Kwong, Bernice Y

2017-12-01

The identification of oncogenic drivers of liquid tumors has led to the rapid development of targeted agents with distinct cutaneous adverse event (AE) profiles. The diagnosis and management of these skin toxicities has motivated a novel partnership between dermatologists and oncologists in developing supportive oncodermatology clinics. In this article we review the current state of knowledge of clinical presentation, mechanisms, and management of the most common and significant cutaneous AEs observed during treatment with targeted therapies for hematologic and lymphoid malignancies. We systematically review according to drug-targeting pathway the cutaneous AE profiles of these drugs, and offer insight when possible into whether pharmacologic target versus immunologic modulation primarily underlie presentation. We include discussion of tyrosine kinase inhibitors (imatinib, dasatinib, nilotinib, bosutinib, ponatinib), blinatumomab, ibrutinib, idelalisib, anti-B cell antibodies (rituximab, ibritumomab, obinutuzumab, ofatumumab, tositumomab), immune checkpoint inhibitors (nivolumab, pembrolizumab), alemtuzumab, brentuximab, and proteasome inhibitors (bortezomib, carfilzomib, ixazomib). We highlight skin reactions seen with antiliquid but not solid tumor agents, draw attention to serious cutaneous AEs that might require therapy modification or cessation, and offer management strategies to permit treatment tolerability. We emphasize the importance of early diagnosis and treatment to minimize disruptions to care, optimize prognosis and quality of life, and promptly address life-threatening skin or infectious events. This evolving partnership between oncologists and dermatologists in the iterative characterization and management of skin toxicities will contribute to a better understanding of these drugs' cutaneous targets and improved patient care. Copyright © 2017 Elsevier Inc. All rights reserved.

Epidermal growth factor receptor and EGFRvIII in glioblastoma: signaling pathways and targeted therapies. | Office of Cancer Genomics

Cancer.gov

Amplification of epidermal growth factor receptor (EGFR) and its active mutant EGFRvIII occurs frequently in glioblastoma (GBM). While EGFR and EGFRvIII play critical roles in pathogenesis, targeted therapy with EGFR-tyrosine kinase inhibitors (TKIs) or antibodies has only shown limited efficacy in patients. Here we discuss signaling pathways mediated by EGFR/EGFRvIII, current therapeutics, and novel strategies to target EGFR/EGFRvIII-amplified GBM.

A view on EGFR-targeted therapies from the oncogene-addiction perspective.

PubMed

Perez, Rolando; Crombet, Tania; de Leon, Joel; Moreno, Ernesto

2013-01-01

Tumor cell growth and survival can often be impaired by inactivating a single oncogen- a phenomenon that has been called as "oncogene addiction." It is in such scenarios that molecular targeted therapies may succeed. among known oncogenes, the epidermal growth factor receptor (EGFR) has become the target of different cancer therapies. So far, however, the clinical benefit from EGFR-targeted therapies has been rather limited. a critical review of the large amount of clinical data obtained with anti-EGFR agents, carried out from the perspective of the oncogene addiction concept, may help to understand the causes of the unsatisfactory results. In this article we intend to do such an exercise taking as basis for the analysis a few case studies of anti-EGFR agents that are currently in the clinic. There, the "EGFR addiction" phenomenon becomes apparent in high-responder patients. We further discuss how the concept of oncogene addiction needs to be interpreted on the light of emerging experimental evidences and ideas; in particular, that EGFR addiction may reflect the interconnection of several cellular pathways. In this regard we set forth several hypotheses; namely, that requirement of higher glucose uptake by hypoxic tumor cells may reinforce EGFR addiction; and that chronic use of EGFR-targeted antibodies in EGFR-addicted tumors would induce stable disease by reversing the malignant phenotype of cancer stem cells and also by sustaining an anti-tumor T cell response. Finally, we discuss possible reasons for the failure of certain combinatorial therapies involving anti-EGFR agents, arguing that some of these agents might produce either a negative or a positive trans-modulation effect on other oncogenes. It becomes evident that we need operational definitions of EGFR addiction in order to determine which patient populations may benefit from treatment with anti-EGFR drugs, and to improve the design of these therapies.

HIV antibodies for treatment of HIV infection

PubMed Central

Margolis, David M.; Koup, Richard A.; Ferrari, Guido

2016-01-01

Summary The bar is high to improve on current combination antiretroviral therapy (ART), now highly effective, safe, and simple. However antibodies that bind the HIV envelope are able to uniquely target the virus as it seeks to enter new target cells, or as it is expressed from previously infected cells. Further, the use of antibodies against HIV as a therapeutic may offer advantages. Antibodies can have long half-lives, and are being considered as partners for long-acting antiretrovirals for use in therapy or prevention of HIV infection. Early studies in animal models and in clinical trials suggest that such antibodies can have antiviral activity but, as with small molecule antiretrovirals, the issues of viral escape and resistance will have to be addressed. Most promising, however, are the unique properties of anti-HIV antibodies: the potential ability to opsonize viral particles, to direct antibody-dependent cellular cytotoxicity (ADCC) against actively infected cells, and ultimately the ability to direct the clearance of HIV-infected cells by effector cells of the immune system. These distinctive activities suggest that HIV antibodies and their derivatives may play an important role in the next frontier of HIV therapeutics, the effort to develop treatments that could lead to an HIV cure. PMID:28133794

The Notch Ligand Jagged1 as a Target for Anti-Tumor Therapy

PubMed Central

Li, Demin; Masiero, Massimo; Banham, Alison H.; Harris, Adrian L.

2014-01-01

The Notch pathway is increasingly attracting attention as a source of therapeutic targets for cancer. Ligand-induced Notch signaling has been implicated in various aspects of cancer biology; as a consequence, pan-Notch inhibitors and therapeutic antibodies targeting one or more of the Notch receptors have been investigated for cancer therapy. Alternatively, Notch ligands provide attractive options for therapy in cancer treatment due to their more restricted expression and better-defined functions, as well as their low rate of mutations in cancer. One of the Notch ligands, Jagged1 (JAG1), is overexpressed in many cancer types, and plays an important role in several aspects of tumor biology. In fact, JAG1-stimulated Notch activation is directly implicated in tumor growth through maintaining cancer stem cell populations, promoting cell survival, inhibiting apoptosis, and driving cell proliferation and metastasis. In addition, JAG1 can indirectly affect cancer by influencing tumor microenvironment components such as tumor vasculature and immune cell infiltration. This article gives an overview of JAG1 and its role in tumor biology, and its potential as a therapeutic target. PMID:25309874

Recent advances in aptamer-armed multimodal theranostic nanosystems for imaging and targeted therapy of cancer.

PubMed

Vandghanooni, Somayeh; Eskandani, Morteza; Barar, Jaleh; Omidi, Yadollah

2018-05-30

The side effects of chemotherapeutics during the course of cancer treatment limit their clinical outcomes. The most important mission of the modern cancer therapy modalities is the delivery of anticancer drugs specifically to the target cells/tissue in order to avoid/reduce any inadvertent non-specific impacts on the healthy normal cells. Nanocarriers decorated with a designated targeting ligand such as aptamers (Aps) and antibodies (Abs) are able to deliver cargo molecules to the target cells/tissue without affecting other neighboring cells, resulting in an improved treatment of cancer. For targeted therapy of cancer, different ligands (e.g., protein, peptide, Abs, Aps and small molecules) have widely been used in the development of different targeting drug delivery systems (DDSs). Of these homing agents, nucleic acid Aps show unique targeting potential with high binding affinity to a variety of biological targets (e.g., genes, peptides, proteins, and even cells and organs). Aps have widely been used as the targeting agent, in large part due to their unique 3D structure, simplicity in synthesis and functionalization, high chemical flexibility, low immunogenicity and toxicity, and cell/tissue penetration capability in some cases. Here, in this review, we provide important insights on Ap-decorated multimodal nanosystems (NSs) and discuss their applications in targeted therapy and imaging of cancer. Copyright © 2018 Elsevier B.V. All rights reserved.

Bioengineering Strategies for Designing Targeted Cancer Therapies

PubMed Central

Wen, Xuejun

2014-01-01

The goals of bioengineering strategies for targeted cancer therapies are (1) to deliver a high dose of an anticancer drug directly to a cancer tumor, (2) to enhance drug uptake by malignant cells, and (3) to minimize drug uptake by nonmalignant cells. Effective cancer-targeting therapies will require both passive- and active targeting strategies and a thorough understanding of physiologic barriers to targeted drug delivery. Designing a targeted therapy includes the selection and optimization of a nanoparticle delivery vehicle for passive accumulation in tumors, a targeting moiety for active receptor-mediated uptake, and stimuli-responsive polymers for control of drug release. The future direction of cancer targeting is a combinatorial approach, in which targeting therapies are designed to use multiple targeting strategies. The combinatorial approach will enable combination therapy for delivery of multiple drugs and dual ligand targeting to improve targeting specificity. Targeted cancer treatments in development and the new combinatorial approaches show promise for improving targeted anticancer drug delivery and improving treatment outcomes. PMID:23768509

A perspective on B-cell-targeting therapy for SLE.

PubMed

Looney, R John; Anolik, Jennifer; Sanz, Inaki

2010-02-01

In recent years, large controlled trials have tested several new agents for systemic lupus erythematosus (SLE). Unfortunately, none of these trials has met its primary outcome. This does not mean progress has not been made. In fact, a great deal has been learned about doing clinical trials in lupus and about the biological and clinical effects of the drugs being tested. Many of these drugs were designed to target B cells directly, e.g., rituximab, belimumab, epratuzumab, and transmembrane activator and calcium modulator and cyclophilin ligand interactor-immunoglobulin (TACI-Ig). The enthusiasm for targeting B cells derives from substantial evidence showing the critical role of B cells in murine models of SLE, as well promising results from multiple open trials with rituximab, a chimeric anti-CD20 monoclonal antibody that specifically depletes B cells (Martin and Chan in Immunity 20(5):517-527, 2004; Sobel et al. in J Exp Med 173:1441-1449, 1991; Silverman and Weisman in Arthritis Rheum 48:1484-1492, 2003; Silverman in Arthritis Rheum 52(4):1342, 2005; Shlomchik et al. in Nat Rev Immunol 1:147-153, 2001; Looney et al. in Arthritis Rheum 50:2580-2589, 2004; Lu et al. in Arthritis Rheum 61(4):482-487, 2009; Saito et al. in Lupus 12(10):798-800, 2003; van Vollenhoven et al. in Scand J Rheumatol 33(6):423-427, 2004; Sfikakis et al. Arthritis Rheum 52(2):501-513, 2005). Why have the controlled trials of B-cell-targeting therapies failed to demonstrate efficacy? Were there flaws in design or execution of these trials? Or, were promising animal studies and open trials misleading, as so often happens? This perspective discusses the current state of B-cell-targeting therapies for human lupus and the future development of these therapies.

Evaluation of anti-podoplanin rat monoclonal antibody NZ-1 for targeting malignant gliomas.

PubMed

Kato, Yukinari; Vaidyanathan, Ganesan; Kaneko, Mika Kato; Mishima, Kazuhiko; Srivastava, Nidhi; Chandramohan, Vidyalakshmi; Pegram, Charles; Keir, Stephen T; Kuan, Chien-Tsun; Bigner, Darell D; Zalutsky, Michael R

2010-10-01

Podoplanin/aggrus is a mucin-like sialoglycoprotein that is highly expressed in malignant gliomas. Podoplanin has been reported to be a novel marker to enrich tumor-initiating cells, which are thought to resist conventional therapies and to be responsible for cancer relapse. The purpose of this study was to determine whether an anti-podoplanin antibody is suitable to target radionuclides to malignant gliomas. The binding affinity of an anti-podoplanin antibody, NZ-1 (rat IgG(2a)), was determined by surface plasmon resonance and Scatchard analysis. NZ-1 was radioiodinated with (125)I using Iodogen [(125)I-NZ-1(Iodogen)] or N-succinimidyl 4-guanidinomethyl 3-[(131)I]iodobenzoate ([(131)I]SGMIB-NZ-1), and paired-label internalization assays of NZ-1 were performed. The tissue distribution of (125)I-NZ-1(Iodogen) and that of [(131)I]SGMIB-NZ-1 were then compared in athymic mice bearing glioblastoma xenografts. The dissociation constant (K(D)) of NZ-1 was determined to be 1.2 × 10(-10) M by surface plasmon resonance and 9.8 × 10(-10) M for D397MG glioblastoma cells by Scatchard analysis. Paired-label internalization assays in LN319 glioblastoma cells indicated that [(131)I]SGMIB-NZ-1 resulted in higher intracellular retention of radioactivity (26.3 ± 0.8% of initially bound radioactivity at 8 h) compared to that from the (125)I-NZ-1(Iodogen) (10.0 ± 0.1% of initially bound radioactivity at 8 h). Likewise, tumor uptake of [(131)I]SGMIB-NZ-1 (39.9 ± 8.8 %ID/g at 24 h) in athymic mice bearing D2159MG xenografts in vivo was significantly higher than that of (125)I-NZ-1(Iodogen) (29.7 ± 6.1 %ID/g at 24 h). The overall results suggest that an anti-podoplanin antibody NZ-1 warrants further evaluation for antibody-based therapy against glioblastoma. Copyright © 2010 Elsevier Inc. All rights reserved.

Tes, a potential Mena-related cancer therapy target.

PubMed

Li, X

2008-02-01

Cancer remains one of the world's most prominent causes of human morbidity and mortality, particularly in developing countries. According to 2005 statistics from the WHO, approximately 7.6 million people died of cancer out of 58 million deaths worldwide, with 9 million people estimated to die from cancer in 2015 and 11.4 million to die in 2030 (http://www.who.int/mediacentre/factsheets/fs297/en/index.html). The principal and internationally recognized methods of cancer treatment are surgery, radiotherapy, chemotherapy, or multimodality therapy. With the recent development of cancer biology, more and more tumor-related targets have been identified, ushering in a new era for target therapy. Every possible step that causes cellular cancer, such as signal transduction pathways, oncogenes and anti-oncogenes, cytokines and receptors, antiangiogenesis, suicide genes, and telomerase (Shay JW, Keith WN. Br J Cancer 2008), that is biologically relevant, reproducibly measurable, and definably correlated with clinical benefit represents a target for target therapies like targeting gene-virotherapy and monoclonal antibody-directed therapy. These therapies can specifically inhibit the growth of tumor cells at the molecular level and even kill them. Generally speaking, cancer-related targets should be crucial to the tumor's malignant phenotype, easily measurable in readily obtained clinical samples, and yield a significant clinical response. Since tumorigenesis is a very complex process involving the interaction of multiple factors and pathways, target treatment offers hopes to maximize efficacy while minimizing toxicity and specificity. More importantly, treatment should have little or no toxicity on normal cells, thus representing the most promising aspect of cancer research (Friday BB, Adjei AA. Clin Cancer Res 2008; 14:342-346). A recent cancer study has provided exciting information. According to Xinhua News from London, Michael Way and fellow researchers from Cancer

Tumor Inhibitory Effect of IRCR201, a Novel Cross-Reactive c-Met Antibody Targeting the PSI Domain.

PubMed

Park, Hyunkyu; Kim, Donggeon; Kim, Eunmi; Sa, Jason K; Lee, Hee Won; Yu, Suji; Oh, Jiwon; Kim, Seok-Hyung; Yoon, Yeup; Nam, Do-Hyun

2017-09-13

Hepatocyte growth factor receptor (HGFR, c-Met) is an essential member of the receptor tyrosine kinase (RTK) family that is often dysregulated during tumor progression, driving a malignant phenotypic state and modulating important cellular functions including tumor growth, invasion, metastasis, and angiogenesis, providing a strong rationale for targeting HGF/c-Met signaling axis in cancer therapy. Based on its protumorigenic potentials, we developed IRCR201, a potent antagonistic antibody targeting the plexin-semaphorin-integrin (PSI) domain of c-Met, using synthetic human antibody phage libraries. We characterized and evaluated the biochemical properties and tumor inhibitory effect of IRCR201 in vitro and in vivo. IRCR201 is a novel fully-human bivalent therapeutic antibody that exhibits cross-reactivity against both human and mouse c-Met proteins with high affinity and specificity. IRCR201 displayed low agonist activity and rapidly depleted total c-Met protein via the lysosomal degradation pathway, inhibiting c-Met-dependent downstream activation and attenuating cellular proliferation in various c-Met-expressing cancer cells. In vivo tumor xenograft models also demonstrated the superior tumor inhibitory responsiveness of IRCR201. Taken together, IRCR201 provides a promising therapeutic agent for c-Met-positive cancer patients through suppressing the c-Met signaling pathway and tumor growth.

Targeted chelation therapy with EDTA-loaded albumin nanoparticles regresses arterial calcification without causing systemic side effects

PubMed Central

Lei, Yang; Nosoudi, Nasim; Vyavahare, Naren

2014-01-01

Background and aims Elastin-specific medial arterial calcification (MAC) is an arterial disease commonly referred as Monckeberg’s sclerosis. It causes significant arterial stiffness, and as yet, no clinical therapy exists to prevent or reverse it. We developed albumin nanoparticles (NPs) loaded with disodium ethylene diaminetetraacetic acid (EDTA) that were designed to target calcified elastic lamina when administrated by intravenous injection. Methods and Results We optimized NP size, charge, and EDTA-loading efficiency (150~200 nm, zeta potential of − 22.89 ~ − 31.72 mV, loading efficiency for EDTA ~20 %) for in vivo targeting in rats. These NPs released EDTA slowly for up to 5 days. In both ex-vivo study and in vivo study with injury-induced local abdominal aortic calcification, we showed that elastin antibody-coated and EDTA-loaded albumin NPs targeted the damaged elastic lamina while sparing healthy artery. Intravenous NP injections reversed elastin-specific MAC in rats after four injections over a 2-week period. EDTA-loaded albumin NPs did not cause the side effects observed in EDTA injection alone, such as decrease in serum calcium (Ca), increase in urine Ca, or toxicity to kidney. There was no bone loss in any treated groups. Conclusion We demonstrate that elastin antibody-coated and EDTA-loaded albumin NPs might be a promising nanoparticle therapy to reverse elastin-specific MAC and circumvent side effects associated with systemic EDTA chelation therapy. PMID:25285609

The collagen receptor uPARAP/Endo180 as a novel target for antibody-drug conjugate mediated treatment of mesenchymal and leukemic cancers

PubMed Central

Nielsen, Christoffer Fagernæs; van Putten, Sander Maarten; Lund, Ida Katrine; Melander, Maria Carlsén; Nørregaard, Kirstine Sandal; Jürgensen, Henrik Jessen; Reckzeh, Kristian; Christensen, Kristine Rothaus; Ingvarsen, Signe Ziir; Gårdsvoll, Henrik; Jensen, Kamilla Ellermann; Hamerlik, Petra; Engelholm, Lars Henning; Behrendt, Niels

2017-01-01

A key task in developing the field of personalized cancer therapy is the identification of novel molecular targets that enable treatment of cancers not susceptible to other means of specific therapy. The collagen receptor uPARAP/Endo180 is overexpressed by malignant cells in several non-epithelial cancers, notably including sarcomas, glioblastomas and subsets of acute myeloid leukemia. In contrast, in healthy adult individuals, expression is restricted to minor subsets of mesenchymal cells. Functionally, uPARAP/Endo180 is a rapidly recycling endocytic receptor that delivers its cargo directly into the endosomal-lysosomal system, thus opening a potential route of entry into receptor-positive cells. This combination of specific expression and endocytic function appears well suited for targeting of uPARAP/Endo180-positive cancers by antibody-drug conjugate (ADC) mediated drug delivery. Therefore, we utilized a specific monoclonal antibody against uPARAP/Endo180, raised through immunization of a uPARAP/Endo180 knock-out mouse, which reacts with both the human and the murine receptor, to construct a uPARAP-directed ADC. This antibody was coupled to the highly toxic dolastatin derivative, monomethyl auristatin E, via a cathepsin-labile valine-citrulline linker. With this ADC, we show strong and receptor-dependent cytotoxicity in vitro in uPARAP/Endo180-positive cancer cell lines of sarcoma, glioblastoma and leukemic origin. Furthermore, we demonstrate the potency of the ADC in vivo in a xenograft mouse model with human uPARAP/Endo180-positive leukemic cells, obtaining a complete cure of all tested mice following intravenous ADC treatment with no sign of adverse effects. Our study identifies uPARAP/Endo180 as a promising target for novel therapy against several highly malignant cancer types. PMID:28574834

Antibody targeting of anaplastic lymphoma kinase induces cytotoxicity of human neuroblastoma

PubMed Central

Carpenter, EL; Haglund, EA; Mace, EM; Deng, D; Martinez, D; Wood, AC; Chow, AK; Weiser, DA; Belcastro, LT; Winter, C; Bresler, SC; Asgharzadeh, S; Seeger, RC; Zhao, H; Guo, R; Christensen, JG; Orange, JS; Pawel, BR; Lemmon, MA; Mossé, YP

2013-01-01

Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase aberrantly expressed in neuroblastoma, a devastating pediatric cancer of the sympathetic nervous system. Germline and somatically acquired ALK aberrations induce increased autophosphorylation, constitutive ALK activation and increased downstream signaling. Thus, ALK is a tractable therapeutic target in neuroblastoma, likely to be susceptible to both small-molecule tyrosine kinase inhibitors and therapeutic antibodies–as has been shown for other receptor tyrosine kinases in malignancies such as breast and lung cancer. Small-molecule inhibitors of ALK are currently being studied in the clinic, but common ALK mutations in neuroblastoma appear to show de novo insensitivity, arguing that complementary therapeutic approaches must be developed. We therefore hypothesized that antibody targeting of ALK may be a relevant strategy for the majority of neuroblastoma patients likely to have ALK-positive tumors. We show here that an antagonistic ALK antibody inhibits cell growth and induces in vitro antibody-dependent cellular cytotoxicity of human neuroblastoma-derived cell lines. Cytotoxicity was induced in cell lines harboring either wild type or mutated forms of ALK. Treatment of neuroblastoma cells with the dual Met/ALK inhibitor crizotinib sensitized cells to antibody-induced growth inhibition by promoting cell surface accumulation of ALK and thus increasing the accessibility of antigen for antibody binding. These data support the concept of ALK-targeted immunotherapy as a highly promising therapeutic strategy for neuroblastomas with mutated or wild-type ALK. PMID:22266870

PET-based compartmental modeling of (124)I-A33 antibody: quantitative characterization of patient-specific tumor targeting in colorectal cancer.

PubMed

Zanzonico, Pat; Carrasquillo, Jorge A; Pandit-Taskar, Neeta; O'Donoghue, Joseph A; Humm, John L; Smith-Jones, Peter; Ruan, Shutian; Divgi, Chaitanya; Scott, Andrew M; Kemeny, Nancy E; Fong, Yuman; Wong, Douglas; Scheinberg, David; Ritter, Gerd; Jungbluth, Achem; Old, Lloyd J; Larson, Steven M

2015-10-01

The molecular specificity of monoclonal antibodies (mAbs) directed against tumor antigens has proven effective for targeted therapy of human cancers, as shown by a growing list of successful antibody-based drug products. We describe a novel, nonlinear compartmental model using PET-derived data to determine the "best-fit" parameters and model-derived quantities for optimizing biodistribution of intravenously injected (124)I-labeled antitumor antibodies. As an example of this paradigm, quantitative image and kinetic analyses of anti-A33 humanized mAb (also known as "A33") were performed in 11 colorectal cancer patients. Serial whole-body PET scans of (124)I-labeled A33 and blood samples were acquired and the resulting tissue time-activity data for each patient were fit to a nonlinear compartmental model using the SAAM II computer code. Excellent agreement was observed between fitted and measured parameters of tumor uptake, "off-target" uptake in bowel mucosa, blood clearance, tumor antigen levels, and percent antigen occupancy. This approach should be generally applicable to antibody-antigen systems in human tumors for which the masses of antigen-expressing tumor and of normal tissues can be estimated and for which antibody kinetics can be measured with PET. Ultimately, based on each patient's resulting "best-fit" nonlinear model, a patient-specific optimum mAb dose (in micromoles, for example) may be derived.

Antibody Therapeutics in Oncology.

PubMed

Wold, Erik D; Smider, Vaughn V; Felding, Brunhilde H

2016-03-01

One of the newer classes of targeted cancer therapeutics is monoclonal antibodies. Monoclonal antibody therapeutics are a successful and rapidly expanding drug class due to their high specificity, activity, favourable pharmacokinetics, and standardized manufacturing processes. Antibodies are capable of recruiting the immune system to attack cancer cells through complement-dependent cytotoxicity or antibody dependent cellular cytotoxicity. In an ideal scenario the initial tumor cell destruction induced by administration of a therapeutic antibody can result in uptake of tumor associated antigens by antigen-presenting cells, establishing a prolonged memory effect. Mechanisms of direct tumor cell killing by antibodies include antibody recognition of cell surface bound enzymes to neutralize enzyme activity and signaling, or induction of receptor agonist or antagonist activity. Both approaches result in cellular apoptosis. In another and very direct approach, antibodies are used to deliver drugs to target cells and cause cell death. Such antibody drug conjugates (ADCs) direct cytotoxic compounds to tumor cells, after selective binding to cell surface antigens, internalization, and intracellular drug release. Efficacy and safety of ADCs for cancer therapy has recently been greatly advanced based on innovative approaches for site-specific drug conjugation to the antibody structure. This technology enabled rational optimization of function and pharmacokinetics of the resulting conjugates, and is now beginning to yield therapeutics with defined, uniform molecular characteristics, and unprecedented promise to advance cancer treatment.

Monoclonal antibody-tagged receptor-targeted contrast agents for detection of cancers

NASA Astrophysics Data System (ADS)

Soukos, N. S.; Hamblin, Michael R.; Deutsch, Thomas F.; Hasan, Tayyaba

2001-07-01

Oral cancer and precancer overexpress the epidermal growth factor receptor (EGFR) and monoclonal antibodies against EGFR coupled to photoactive dyes may have a potential both as a diagnostic and treatment modalities for oral premalignancy. We asked whether an anti-EGFR mab (C225) conjugated with the fluorescence dye indocyanine Cy5.5 could detect dysplastic changes in the hamster cheek pouch carcinogenesis model. Secondly, we tested whether the same antibody conjugated with the photosensitizer chlorin (e6) could be used together with illumination to reduce levels of expression of EGFR as evaluated by the immunophotodetection procedure. Increased fluorescence appeared to correlate with development of premalignancy when the C225-Cy5.5 conjugate was used. Areas with increased fluorescence signal were found in carcinogen-treated but clinically normal cheek pouches, that revealed dysplastsic changes by histology. The immunophotodetection procedure was carried out after photoummunotherapy with the C225-ce6 conjugate, and showed a significant reduction in fluorescence in the illuminated compared to the non-illuminated areas in the carcinogen- treated but not the normal cheek pouch. The results demonstrate that the use of anti-EGFR Mab targeted photoactive dyes may serve as a feedback controlled optical diagnosis and therapy procedure for oral premalignant lesions.

Targeting of antibody-conjugated plasminogen activators to the pulmonary vasculature.

PubMed

Muzykantov, V R; Barnathan, E S; Atochina, E N; Kuo, A; Danilov, S M; Fisher, A B

1996-11-01

Thrombolytic therapy has not been widely used for pulmonary embolism due to less than optimal results with conventional plasminogen activators. We propose a new approach to deliver plasminogen activators to the luminal surface of the pulmonary vasculature to potentially improve dissolution of pulmonary thromboemboli. Our previous studies have documented that a monoclonal antibody (mAb) to angiotensin-converting enzyme (anti-angiotensin-converting enzyme mAb 9B9) accumulates in the lungs of various animal species after systemic administration. We coupled 125I-labeled biotinylated plasminogen activators (single-chain urokinase plasminogen activator, tissue-type plasminogen activator and streptokinase) to biotinylated mAb 9B9, using streptavidin as a cross-linker. The fibrinolytic activity of plasminogen activators was not changed significantly by either biotinylation or by coupling to streptavidin. Antibody-conjugated plasminogen activators bind to the antigen immobilized in plastic wells and provide lysis of fibrin clots formed in these wells. Therefore, antibody-conjugated plasminogen activators bound to their target antigen retain their capacity to activate plasminogen. One hour after i.v. injection of mAb 9B9-conjugated radiolabeled biotinylated single-chain urokinase plasminogen activator, biotinylated tissue-type plasminogen activator or biotinylated-streptokinase in rats, the level of radiolabel was 7.4 +/- 0.8, 5.9 +/- 0.4 and 3.6 +/- 0.4% of injected dose/g (ID/g) of lung tissue vs. 0.5 +/- 0.01, 0.3 +/- 0.01 and 0.6 +/- 0.3% ID/g after injection of the same activators conjugated with control mouse IgG (P < .01 in all cases). Injection of mAb 9B9-conjugated radiolabeled plasminogen activator led to its rapid pulmonary uptake with a peak value 6.2 +/- 1.2% ID/g attained 3 hr after injection. One day later, 2.2 +/- 0.5% of the injected radioactivity was found per gram of lung tissue, although the blood level was 0.13 +/- 0.03% ID/g (lung/blood ratio 16.7 +/- 0

Ovarian stimulation in young adult cancer survivors on targeted cancer therapies

PubMed Central

Su, H. Irene; Connell, Meghan W.; Bazhenova, Lyudmila A.

2016-01-01

Objective To describe a clinical approach to and outcomes of in vitro fertilization in reproductive-aged cancer survivors on targeted cancer therapies. Design Case report Setting Academic fertility preservation program Patients The first case is of a female patient with metastatic lung cancer on long-term crizotinib, an ALK inhibitor. The second case is of a female patient with metastatic colon cancer on long-term denosumab, a RANKL antibody. Both patients presented desiring fertility. Interventions In vitro fertilization Main outcome measures Live birth and embryo banking Results The potential impact of targeted therapy on oocytes and pregnancy was investigated via literature review and pharmaceutical company inquiries. Following oncologic, fertility and psychological counseling, both survivors underwent ovarian stimulation, in vitro fertilization and preimplantation genetic screening. One couple achieved live births of dizygotic twins via gestational surrogacy. The second couple froze one euploid blastocyst for future fertility. Both survivors are stable from their cancer standpoints. Conclusion Successful fertility treatments are possible in the context of exposure to crizotinib, and denosumab. PMID:27565250

Anti-CD22 and anti-CD79b antibody-drug conjugates preferentially target proliferating B cells.

PubMed

Fuh, Franklin K; Looney, Caroline; Li, Dongwei; Poon, Kirsten A; Dere, Randall C; Danilenko, Dimitry M; McBride, Jacqueline; Reed, Chae; Chung, Shan; Zheng, Bing; Mathews, William Rodney; Polson, Andrew; Prabhu, Saileta; Williams, Marna

2017-04-01

CD22 and CD79b are cell-surface receptors expressed on B-cell-derived malignancies such as non-Hodgkin's lymphoma (NHL). An anti-mitotic agent, monomethyl auristatin E, was conjugated to anti-CD22 and anti-CD79b antibodies to develop target-specific therapies for NHL. The mechanism of action (MOA) and pharmacological and pharmacokinetic (PK) profiles of these antibody-drug conjugates (ADCs) were investigated in cynomolgus monkeys. Animals were administered anti-CD22 or anti-CD79b ADCs, respective unconjugated antibodies or vehicle. Pharmacodynamic effects on total and proliferating B cells and serum PK were then assessed. Antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) of the ADCs were evaluated in vitro. Depletion of B cells was observed after administration of either ADC or the respective unconjugated antibodies. An extended duration of depletion was observed in animals administered ADCs. Similarly, preferential depletion of proliferating B cells in blood and germinal centre B cells in spleen were only observed in animals administered ADCs. Serum PK profiles of ADCs and respective unconjugated antibodies were comparable. In vitro, anti-human CD22 and anti-human CD79b antibodies showed no or only moderate ADCC activity, respectively; neither antibody had CDC activity. The findings support the proposed MOA: initial depletion of total B cells by antibody-mediated opsonization, followed by preferential, sustained depletion of proliferating B cells by the auristatin conjugate due to its anti-mitotic action. Delivering potent anti-mitotic agents to B cells via the specificity of monoclonal antibodies provides a means to eliminate pathogenic B cells in NHL with improved risk-benefit profiles over traditional chemotherapeutics. © 2016 Genentech. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

In Vitro Methods for Comparing Target Binding and CDC Induction Between Therapeutic Antibodies: Applications in Biosimilarity Analysis.

PubMed

Salinas-Jazmín, Nohemi; González-González, Edith; Vásquez-Bochm, Luz X; Pérez-Tapia, Sonia M; Velasco-Velázquez, Marco A

2017-05-04

Therapeutic monoclonal antibodies (mAbs) are relevant to the treatment of different pathologies, including cancers. The development of biosimilar mAbs by pharmaceutical companies is a market opportunity, but it is also a strategy to increase drug accessibility and reduce therapy-associated costs. The protocols detailed here describe the evaluation of target binding and CDC induction by rituximab in Daudi cells. These two functions require different structural regions of the antibody and are relevant to the clinical effect induced by rituximab. The protocols allow the side-to-side comparison of a reference rituximab and a marketed rituximab biosimilar. The evaluated products showed differences both in target binding and CDC induction, suggesting that there are underlying physicochemical differences and highlighting the need to analyze the impact of those differences in the clinical setting. The methods reported here constitute simple and inexpensive in vitro models for the evaluation of the activity of rituximab biosimilars. Thus, they can be useful during biosimilar development, as well as for quality control in biosimilar production. Furthermore, the presented methods can be extrapolated to other therapeutic mAbs.

Antineutrophil cytoplasmic antibody associated vasculitides with renal involvement: Open challenges in the remission induction therapy.

PubMed

Salvadori, Maurizio; Tsalouchos, Aris

2018-05-06

Renal involvement with rapidly progressive glomerulonephritis is a common manifestation of antineutrophil cytoplasmic antibody (ANCA) associated vasculitides, which is characterized by end-stage renal disease and high mortality rates in untreated and/or late referral patients. The long-term renal survival has improved dramatically since the addition of cyclophosphamide (CYC) and recently of rituximab (RTX) in association with corticosteroids in the remission induction therapeutic regimens. However, renal prognosis remains unfavorable for many patients and the mortality rate is still significantly high. In this review, we analyze the open challenges to be addressed to optimize the induction remission therapy, principally in patients with advanced kidney failure. This concern the first-line therapy (CYC or RTX) based on different parameters (estimated glomerular filtration rate at baseline, new or relapsed disease, ANCA specificity, tissue injury, safety), the role of plasma exchange and the role of new therapies. Indeed, we discuss future perspectives in induction remission therapy by reporting recent advances in new targeted therapies with particular reference to avacopan, an orally administered selective C5a receptor inhibitor.

Antineutrophil cytoplasmic antibody associated vasculitides with renal involvement: Open challenges in the remission induction therapy

PubMed Central

Salvadori, Maurizio; Tsalouchos, Aris

2018-01-01

Renal involvement with rapidly progressive glomerulonephritis is a common manifestation of antineutrophil cytoplasmic antibody (ANCA) associated vasculitides, which is characterized by end-stage renal disease and high mortality rates in untreated and/or late referral patients. The long-term renal survival has improved dramatically since the addition of cyclophosphamide (CYC) and recently of rituximab (RTX) in association with corticosteroids in the remission induction therapeutic regimens. However, renal prognosis remains unfavorable for many patients and the mortality rate is still significantly high. In this review, we analyze the open challenges to be addressed to optimize the induction remission therapy, principally in patients with advanced kidney failure. This concern the first-line therapy (CYC or RTX) based on different parameters (estimated glomerular filtration rate at baseline, new or relapsed disease, ANCA specificity, tissue injury, safety), the role of plasma exchange and the role of new therapies. Indeed, we discuss future perspectives in induction remission therapy by reporting recent advances in new targeted therapies with particular reference to avacopan, an orally administered selective C5a receptor inhibitor. PMID:29736379

Targeting chemotherapy-resistant leukemia by combining DNT cellular therapy with conventional chemotherapy.

PubMed

Chen, Branson; Lee, Jong Bok; Kang, Hyeonjeong; Minden, Mark D; Zhang, Li

2018-04-24

While conventional chemotherapy is effective at eliminating the bulk of leukemic cells, chemotherapy resistance in acute myeloid leukemia (AML) is a prevalent problem that hinders conventional therapies and contributes to disease relapse, and ultimately patient death. We have recently shown that allogeneic double negative T cells (DNTs) are able to target the majority of primary AML blasts in vitro and in patient-derived xenograft models. However, some primary AML blast samples are resistant to DNT cell therapy. Given the differences in the modes of action of DNTs and chemotherapy, we hypothesize that DNT therapy can be used in combination with conventional chemotherapy to further improve their anti-leukemic effects and to target chemotherapy-resistant disease. Drug titration assays and flow-based cytotoxicity assays using ex vivo expanded allogeneic DNTs were performed on multiple AML cell lines to identify therapy-resistance. Primary AML samples were also tested to validate our in vitro findings. Further, a xenograft model was employed to demonstrate the feasibility of combining conventional chemotherapy and adoptive DNT therapy to target therapy-resistant AML. Lastly, blocking assays with neutralizing antibodies were employed to determine the mechanism by which chemotherapy increases the susceptibility of AML to DNT-mediated cytotoxicity. Here, we demonstrate that KG1a, a stem-like AML cell line that is resistant to DNTs and chemotherapy, and chemotherapy-resistant primary AML samples both became more susceptible to DNT-mediated cytotoxicity in vitro following pre-treatment with daunorubicin. Moreover, chemotherapy treatment followed by adoptive DNT cell therapy significantly decreased bone marrow engraftment of KG1a in a xenograft model. Mechanistically, daunorubicin increased the expression of NKG2D and DNAM-1 ligands on KG1a; blocking of these pathways attenuated DNT-mediated cytotoxicity. Our results demonstrate the feasibility and benefit of using DNTs as

Longitudinal trends in use and costs of targeted therapies for common cancers in Taiwan: a retrospective observational study

PubMed Central

Hsu, Jason C; Lu, Christine Y

2016-01-01

Objectives Some targeted therapies have improved survival and overall quality of cancer care generally, but these increasingly expensive medicines have led to increases in pharmaceutical expenditure. This study examined trends in use and expenditures of antineoplastic agents in Taiwan, and estimated market shares by prescription volume and costs of targeted therapies over time. We also determined which cancer types accounted for the highest use of targeted therapies. Design This is a retrospective observational study focusing on the utilisation of targeted therapies for treatment of cancer. Setting The monthly claims data for antineoplastic agents were retrieved from Taiwan's National Health Insurance Research Database (2009–2012). Main outcome measures We calculated market shares by prescription volume and costs for each class of antineoplastic agent by cancer type. Using a time series design with Autoregressive Integrated Moving Average (ARIMA) models, we estimated trends in use and costs of targeted therapies. Results Among all antineoplastic agents, use of targeted therapies grew from 6.24% in 2009 to 12.29% in 2012, but their costs rose from 26.16% to 41.57% in that time. Monoclonal antibodies and protein kinase inhibitors contributed the most (respectively, 23.84% and 16.12% of costs for antineoplastic agents in 2012). During 2009–2012, lung (44.64% of use; 28.26% of costs), female breast (16.49% of use; 27.18% of costs) and colorectal (12.11% of use; 13.16% of costs) cancers accounted for the highest use of targeted therapies. Conclusions In Taiwan, targeted therapies are increasingly used for different cancers, representing a substantial economic burden. It is important to establish mechanisms to monitor their use and outcomes. PMID:27266775

Combining Active Immunization with Monoclonal Antibody Therapy to Facilitate Early Initiation of a Long-acting Anti-methamphetamine Antibody Response

PubMed Central

Hambuchen, Michael D.; Carroll, F. Ivy; Rüedi-Bettschen, Daniela; Hendrickson, Howard P.; Hennings, Leah J.; Blough, Bruce E.; Brieaddy, Lawrence E.; Pidaparthi, Ramakrishna R.; Owens, S. Michael

2015-01-01

We hypothesized that an anti-METH mAb could be used in combination with a METH-conjugate vaccine (MCV) to safely improve the overall quality and magnitude of the anti-METH immune response. The benefits would include immediate onset of action (from the mAb), timely increases in the immune responses (from the combined therapy) and duration of antibody response that could last for months (from the MCV). A novel METH-like hapten (METH-SSOO9) was synthesized and then conjugated to immunocyanin monomers of Keyhole limpet hemocyanin (ICKLH) to create the MCV, ICKLH-SOO9. The vaccine, in combination with previously discovered anti-METH mAb7F9, was then tested in rats for safety and potential efficacy. The combination antibody therapy allowed safe achievement of an early high anti-METH antibody response, which persisted throughout the study. Indeed, even after four months the METH vaccine antibodies still had the capacity to significantly reduce METH brain concentrations resulting from a 0.56 mg/kg METH dose. PMID:25973614

Antibodies and Selection of Monoclonal Antibodies.

PubMed

Hanack, Katja; Messerschmidt, Katrin; Listek, Martin

Monoclonal antibodies are universal binding molecules with a high specificity for their target and are indispensable tools in research, diagnostics and therapy. The biotechnological generation of monoclonal antibodies was enabled by the hybridoma technology published in 1975 by Köhler and Milstein. Today monoclonal antibodies are used in a variety of applications as flow cytometry, magnetic cell sorting, immunoassays or therapeutic approaches. First step of the generation process is the immunization of the organism with appropriate antigen. After a positive immune response the spleen cells are isolated and fused with myeloma cells in order to generate stable, long-living antibody-producing cell lines - hybridoma cells. In the subsequent identification step the culture supernatants of all hybridoma cells are screened weekly for the production of the antibody of interest. Hybridoma cells producing the antibody of interest are cloned by limited dilution till a monoclonal hybridoma is found. This is a very time-consuming and laborious process and therefore different selection strategies were developed since 1975 in order to facilitate the generation of monoclonal antibodies. Apart from common automation of pipetting processes and ELISA testing there are some promising approaches to select the right monoclonal antibody very early in the process to reduce time and effort of the generation. In this chapter different selection strategies for antibody-producing hybridoma cells are presented and analysed regarding to their benefits compared to conventional limited dilution technology.

Combinational Therapy Enhances the Effects of Anti-IGF-1R mAb Figitumumab to Target Small Cell Lung Cancer

PubMed Central

Shen, Hongchang; Xu, Jun; Zhu, Linhai; Liu, Qi; Du, Jiajun

2015-01-01

Background Small cell lung cancer (SCLC) is a recalcitrant malignancy with distinct biologic properties. Antibody targeting therapy has been actively investigated as a new drug modality. Methods We tested the expression of IGF-1R and calculated the survival in 61 SCLC patients. We also evaluated the anti-tumor effects of anti-IGF-1R monoclonal antibody Figitumumab (CP) on SCLC, and tried two drug combinations to improve CP therapy. Results Our clinical data suggested that high IGF-1R expression was correlated with low SCLC patient survival. We then demonstrated the effect of CP was likely through IGF-1R blockage and down-regulation without IGF-1R auto-phosphorylation and PI3K/AKT activation. However, we observed elevated MEK/ERK activation upon CP treatment in SCLC cells, and this MEK/ERK activation was enhanced by ß-arrestin1 knockdown while attenuated by ß-arrestin2 knockdown. We found both MEK/ERK inhibitor and metformin could enhance CP treatment in SCLC cells. We further illustrated the additive effect of metformin was likely through promoting further IGF-1R down-regulation. Conclusion Our results highlighted the potential of anti-IGF-1R therapy and the adjuvant therapy strategy with either MEK/ERK inhibitor or metformin to target SCLC, warranting further studies. PMID:26287334

Antibody-targeted interleukin 2 stimulates T-cell killing of autologous tumor cells.

PubMed Central

Gillies, S D; Reilly, E B; Lo, K M; Reisfeld, R A

1992-01-01

A genetically engineered fusion protein consisting of a chimeric anti-ganglioside GD2 antibody (ch14.18) and interleukin 2 (IL2) was tested for its ability to enhance the killing of autologous GD2-expressing melanoma target cells by a tumor-infiltrating lymphocyte line (660 TIL). The fusion of IL2 to the carboxyl terminus of the immunoglobulin heavy chain did not reduce IL2 activity as measured in a standard proliferation assay using either mouse or human T-cell lines. Antigen-binding activity was greater than that of the native chimeric antibody. The ability of resting 660 TIL cells to kill their autologous GD2-positive target cells was enhanced if the target cells were first coated with the fusion protein. This stimulation of killing was greater than that of uncoated cells in the presence of equivalent or higher concentrations of free IL2. Such antibody-cytokine fusion proteins may prove useful in targeting the biological effect of IL2 and other cytokines to tumor cells and in this way stimulate their immune destruction. Images PMID:1741398

Targeted therapies: a nursing perspective.

PubMed

Kay, Polly

2006-02-01

To review the development of targeted therapies and the biology of relevant therapeutic targets. To analyze the relevance of targeted agents as part of current clinical practice. Research articles. Several targeted agents are now available for clinical use. Their mechanisms of action are more specific against tumor cells than traditional cytotoxics. Monotherapy regimens based on targeted agents tend to be better tolerated than chemotherapy, and most combination regimens with targeted agents have proven feasible. Their availability has greatly expanded cancer treatment options, especially for chemorefractory patients. Nurses involved in the care of patients with cancer can benefit from an increased understanding of targeted therapies, including their mechanisms of action, their efficacy profile, as well as prophylaxis and management of adverse events and administration procedures.

Macrophage-mediated trogocytosis leads to death of antibody-opsonized tumor cells

PubMed Central

Velmurugan, Ramraj; Challa, Dilip K.; Ram, Sripad; Ober, Raimund J.; Ward, E. Sally

2016-01-01

Understanding the complex behavior of effector cells such as monocytes or macrophages in regulating cancerous growth is of central importance for cancer immunotherapy. Earlier studies using CD20-specific antibodies have demonstrated that the Fcγ receptor (FcγR)-mediated transfer of the targeted receptors from tumor cells to these effector cells through trogocytosis can enable escape from antibody therapy, leading to the viewpoint that this process is pro-tumorigenic. In the current study we demonstrate that persistent trogocytic attack results in the killing of HER2-overexpressing breast cancer cells. Further, antibody engineering to increase FcγR interactions enhances this tumoricidal activity. These studies extend the complex repertoire of activities of macrophages to trogocytic-mediated cell death of HER2-overexpressing target cells and have implications for the development of effective antibody-based therapies. PMID:27226489

Gaining insights into the consequences of target-mediated drug disposition of monoclonal antibodies using quasi-steady-state approximations.

PubMed

Grimm, Hans Peter

2009-10-01

Target-mediated drug disposition (TMDD) is frequently reported for therapeutic monoclonal antibodies and is linked to the high affinity and high specificity of antibody molecules for their target. Understanding TMDD of a monoclonal antibody should go beyond the empirical description of its non-linear PK since valuable insights on the antibody-target interaction itself can be gained. This makes its mechanistic understanding precious for the drug development process, in particular for the optimization of new antibody molecules, for the design and interpretation of pharmacokinetic studies, and possibly even for the evaluation of efficacy and dose selection of drug candidates. Using the observation that the molecular (microscopic) processes are usually much more rapid than the pharmacokinetic (macroscopic) processes, a series of quasi-steady-state conditions on the microscopic level is proposed to bridge the gap between simple empirical and complex mechanistic descriptions of TMDD. These considerations show the impact of parameters such as target turnover, target expression, and target accessibility on the pharmacokinetics and pharmacodynamics of monoclonal antibodies.

Intracellular and non-neuronal targets of voltage-gated potassium channel complex antibodies

PubMed Central

Lang, Bethan; Makuch, Mateusz; Moloney, Teresa; Dettmann, Inga; Mindorf, Swantje; Probst, Christian; Stoecker, Winfried; Buckley, Camilla; Newton, Charles R; Leite, M Isabel; Maddison, Paul; Komorowski, Lars; Adcock, Jane; Vincent, Angela; Waters, Patrick; Irani, Sarosh R

2017-01-01

Objectives Autoantibodies against the extracellular domains of the voltage-gated potassium channel (VGKC) complex proteins, leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein-2 (CASPR2), are found in patients with limbic encephalitis, faciobrachial dystonic seizures, Morvan's syndrome and neuromyotonia. However, in routine testing, VGKC complex antibodies without LGI1 or CASPR2 reactivities (double-negative) are more common than LGI1 or CASPR2 specificities. Therefore, the target(s) and clinical associations of double-negative antibodies need to be determined. Methods Sera (n=1131) from several clinically defined cohorts were tested for IgG radioimmunoprecipitation of radioiodinated α-dendrotoxin (125I-αDTX)-labelled VGKC complexes from mammalian brain extracts. Positive samples were systematically tested for live hippocampal neuron reactivity, IgG precipitation of 125I-αDTX and 125I-αDTX-labelled Kv1 subunits, and by cell-based assays which expressed Kv1 subunits, LGI1 and CASPR2. Results VGKC complex antibodies were found in 162 of 1131 (14%) sera. 90 of these (56%) had antibodies targeting the extracellular domains of LGI1 or CASPR2. Of the remaining 72 double-negative sera, 10 (14%) immunoprecipitated 125I-αDTX itself, and 27 (38%) bound to solubilised co-expressed Kv1.1/1.2/1.6 subunits and/or Kv1.2 subunits alone, at levels proportionate to VGKC complex antibody levels (r=0.57, p=0.0017). The sera with LGI1 and CASPR2 antibodies immunoprecipitated neither preparation. None of the 27 Kv1-precipitating samples bound live hippocampal neurons or Kv1 extracellular domains, but 16 (59%) bound to permeabilised Kv1-expressing human embryonic kidney 293T cells. These intracellular Kv1 antibodies mainly associated with non-immune disease aetiologies, poor longitudinal clinical–serological correlations and a limited immunotherapy response. Conclusions Double-negative VGKC complex antibodies are often directed against cytosolic epitopes of

Targeting gene therapy to cancer: a review.

PubMed

Dachs, G U; Dougherty, G J; Stratford, I J; Chaplin, D J

1997-01-01

In recent years the idea of using gene therapy as a modality in the treatment of diseases other than genetically inherited, monogenic disorders has taken root. This is particularly obvious in the field of oncology where currently more than 100 clinical trials have been approved worldwide. This report will summarize some of the exciting progress that has recently been made with respect to both targeting the delivery of potentially therapeutic genes to tumor sites and regulating their expression within the tumor microenvironment. In order to specifically target malignant cells while at the same time sparing normal tissue, cancer gene therapy will need to combine highly selective gene delivery with highly specific gene expression, specific gene product activity, and, possibly, specific drug activation. Although the efficient delivery of DNA to tumor sites remains a formidable task, progress has been made in recent years using both viral (retrovirus, adenovirus, adeno-associated virus) and nonviral (liposomes, gene gun, injection) methods. In this report emphasis will be placed on targeted rather than high-efficiency delivery, although those would need to be combined in the future for effective therapy. To date delivery has been targeted to tumor-specific and tissue-specific antigens, such as epithelial growth factor receptor, c-kit receptor, and folate receptor, and these will be described in some detail. To increase specificity and safety of gene therapy further, the expression of the therapeutic gene needs to be tightly controlled within the target tissue. Targeted gene expression has been analyzed using tissue-specific promoters (breast-, prostate-, and melanoma-specific promoters) and disease-specific promoters (carcinoembryonic antigen, HER-2/neu, Myc-Max response elements, DF3/MUC). Alternatively, expression could be regulated externally with the use of radiation-induced promoters or tetracycline-responsive elements. Another novel possibility that will be

Monoclonal antibodies and recombinant immunoglobulins for the treatment of multiple sclerosis.

PubMed

Gensicke, Henrik; Leppert, David; Yaldizli, Özgür; Lindberg, Raija L P; Mehling, Matthias; Kappos, Ludwig; Kuhle, Jens

2012-01-01

Multiple sclerosis (MS) is an inflammatory and degenerative disease leading to demyelination and axonal damage in the CNS. Autoimmunity plays a central role in MS pathogenesis. Per definition, monoclonal antibodies are recombinant biological compounds with a well defined target, thus carrying the promise of targeting pathogenic cells or molecules with high specificity, avoiding undesired off-target effects. Natalizumab was the first monoclonal antibody to be approved for the treatment of MS. Several other monoclonal antibodies are in development and have demonstrated promising efficacy in phase II studies. They can be categorized according to their mode of action into compounds targeting (i) leukocyte migration into the CNS (natalizumab); (ii) cytolytic antibodies (rituximab, ocrelizumab, ofatumumab, alemtuzumab); or (iii) antibodies and recombinant proteins targeting cytokines and chemokines and their receptors (daclizumab, ustekinumab, atacicept, tabalumab [Ly-2127399], secukinumab [AIN457]). In this review, we discuss the specific molecular targets, clinical efficacy and safety of these compounds and discuss criteria to anticipate the position of monoclonal antibodies in the diversifying armamentarium of MS therapy in the coming years.

Characterization and Imaging of Antibody-Coated Gold Nanoparticles for Targeted Treatment of Microbial Keratitis

NASA Astrophysics Data System (ADS)

Mahan, Matthew

Microbial keratitis (MK) is an infection of the cornea by pathogenic organisms that causes inflammation and irritation. It can lead to full or partial blindness if left untreated. Current clinical treatment methods rely on high frequency application of topical drugs which are subject to the issues of patient compliance and microbial resistance. In this work, gold nanoparticles (AuNP) were proposed as an alternative treatment method in light-based therapies. Particle formulation methods were investigated and assessed using transmission electron microscopy (TEM) and ultraviolet/visible spectroscopy (UV-Vis). AuNP of 20 nm diameter were used as platforms to attach monoclonal antibodies anti-FLAG or anti-F1 to enhance their cell-targeting ability as well as polyethylene glycol to reduce non-specific binding and protein adsorption. These functionalized particles were qualitatively assessed using UV-Vis. The antibody-functionalized AuNP were then assessed for their ability to attach directly to Pseudomonas aeruginosa, expressing FLAG peptide, or Aspergillus fumigatus, expressing the F1 receptor. Attachment was imaged using dark field microscopy, transmission electron microscopy, and fluorescence microscopy.

Anti-CD30-targeted gold nanoparticles for photothermal therapy of L-428 Hodgkin’s cell

PubMed Central

Qu, Xiaochao; Yao, Cuiping; Wang, Jing; Li, Zheng; Zhang, Zhenxi

2012-01-01

Purpose Due to the efficient bioconjugation and highly photothermal effect, gold nanoparticles can stain receptor-overexpressing cancer cells through specific targeting of ligands to receptors, strongly absorb specific light and efficiently convert it into heat based on the property of surface plasmon resonance, and then induce the localized protein denaturation and cell death. Methods Two gold nanoparticle–antibody conjugates, gold-BerH2 antibody (anti-CD30 receptor) and gold-ACT1 antibody (anti-CD25-receptor), were synthesized. Gold-BerH2 conjugates can specifically bind to the surface of L-428 Hodgkin’s cells, and gold-ACT1 conjugates were used for the control. The gold nanoparticle-induced L-428 cell-killing experiments were implemented with different experimental parameters. Results At a relatively low concentration of gold and short incubation time, the influence of cytotoxicity of gold on cell viability can be overlooked. Under laser irradiation at suitable power, the high killing efficiency of gold-targeted L-428 cells was achieved, but little damage was done to nontargeted cancer cells. Conclusion Gold nanoparticle-mediated photothermal therapy provides a relatively safe therapeutic technique for cancer treatment. PMID:23269868

Fabry disease, enzyme replacement therapy and the significance of antibody responses.

PubMed

Deegan, Patrick B

2012-03-01

Fabry disease is an X-linked disorder caused by a deficiency of α-galactosidase A. This leads to a progressive accumulation of globotriaosylceramide in tissues throughout the body. Cardiac, renal and neurological manifestations are common and life expectancy is significantly reduced relative to the general population. Management of Fabry disease involves the administration of intravenous enzyme replacement therapy (ERT). Two forms - agalsidase alfa and agalsidase beta - have been licensed in certain jurisdictions and are generally well tolerated; however, some patients develop antibodies to the infused enzyme, which may impair the efficacy and safety of treatment. Agalsidase alfa and agalsidase beta are produced in different systems; this leads to certain differences in post-translational modification that may affect immunogenicity. Immunoglobulin (Ig) G antibodies have frequently been reported in patients with Fabry disease receiving ERT; IgG responses are reported in a greater proportion of patients receiving agalsidase beta than in patients receiving agalsidase alfa. IgE antibodies are less common than IgG antibodies, and have not been observed in patients receiving agalsidase alfa. However, these data are difficult to interpret due to methodological differences in the assessment of seropositivity, and in the doses of enzyme used. The clinical impact of the development of IgG antibodies to ERT in patients with Fabry disease remains unclear, due to lack of data and to the marked heterogeneity of patients both in terms of disease manifestations and response to therapy. Further studies that examine the development of antibodies in patients with Fabry disease and the potential impact of such antibodies on the outcome of ERT are necessary.

Trispecific antibodies for CD16A-directed NK cell engagement and dual-targeting of tumor cells.

PubMed

Gantke, Thorsten; Weichel, Michael; Herbrecht, Carmen; Reusch, Uwe; Ellwanger, Kristina; Fucek, Ivica; Eser, Markus; Müller, Thomas; Griep, Remko; Molkenthin, Vera; Zhukovsky, Eugene A; Treder, Martin

2017-09-01

Bispecific antibodies that redirect the lytic activity of cytotoxic immune effector cells, such as T- and NK cells, onto tumor cells have emerged as a highly attractive and clinically validated treatment modality for hematological malignancies. Advancement of this therapeutic concept into solid tumor indications, however, is hampered by the scarcity of targetable antigens that are surface-expressed on tumor cells but demonstrate only limited expression on healthy tissues. To overcome this limitation, the concept of dual-targeting, i.e. the simultaneous targeting of two tumor-expressed surface antigens with limited co-expression on non-malignant cells, with multispecific antibodies has been proposed to increase tumor selectivity of antibody-induced effector cell cytotoxicity. Here, a novel CD16A (FcγRIIIa)-directed trispecific, tetravalent antibody format, termed aTriFlex, is described, that is capable of redirecting NK cell cytotoxicity to two surface-expressed antigens. Using a BCMA/CD200-based in vitro model system, the potential use of aTriFlex antibodies for dual-targeting and selective induction of NK cell-mediated target cell lysis was investigated. Bivalent bispecific target cell binding was found to result in significant avidity gains and up to 17-fold increased in vitro potency. These data suggest trispecific aTriFlex antibodies may support dual-targeting strategies to redirect NK cell cytotoxicity with increased selectivity to enable targeting of solid tumor antigens. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Nuclear and Fluorescent Labeled PD-1-Liposome-DOX-64Cu/IRDye800CW Allows Improved Breast Tumor Targeted Imaging and Therapy.

PubMed

Du, Yang; Liang, Xiaolong; Li, Yuan; Sun, Ting; Jin, Zhengyu; Xue, Huadan; Tian, Jie

2017-11-06

The overexpression of programmed cell death-1 (PD-1) in tumors as breast cancer makes it a possible target for cancer imaging and therapy. Advances in molecular imaging, including radionuclide imaging and near-infrared fluorescence (NIRF) imaging, enable the detection of tumors with high sensitivity. In this study, we aim to develop a novel PD-1 antibody targeted positron emission tomography (PET) and NIRF labeled liposome loaded with doxorubicin (DOX) and evaluate its application for in vivo cancer imaging and therapy. IRDye800CW and 64 Cu were conjugated to liposomes with PD-1 antibody labeling, and DOX was inside the liposomes to form theranostic nanoparticles. The 4T1 tumors were successfully visualized with PD-1-Liposome-DOX- 64 Cu/IRDye800CW using NIRF/PET imaging. The bioluminescent imaging (BLI) results showed that tumor growth was significantly inhibited in the PD-1-Liposome-DOX-treated group than the IgG control. Our results highlight the potential of using dual-labeled theranostic PD-1 mAb-targeted Liposome-DOX- 64 Cu/IRDye800CW for the management of breast tumor.

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

PubMed

Press, Michael F; Lenz, Heinz-Josef

2007-01-01

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

Targeted therapies for cancer

MedlinePlus

Targeted therapies are promising new treatments, but they have limitations. Cancer cells can become resistant to these drugs. The target sometimes changes, so the treatment no longer works. The cancer may find a different way to grow and survive that ...

EphA2 Targeted Chemotherapy Using an Antibody Drug Conjugate in Endometrial Carcinoma

PubMed Central

Lee, Jeong-Won; Stone, Rebecca L.; Lee, Sun Joo; Nam, Eun Ji; Roh, Ju-Won; Nick, Alpa M.; Han, Hee-Dong; Shahzad, Mian M.K.; Kim, Hye-Sun; Mangala, Lingegowda S.; Jennings, Nicholas B.; Mao, Shenlan; Gooya, John; Jackson, Dowdy; Coleman, Robert L.; Sood, Anil K.

2013-01-01

Purpose EphA2 overexpression is frequently observed in endometrial cancers, and is predictive of poor clinical outcome. Here, we utilize an antibody drug conjugate (MEDI-547) composed of a fully human monoclonal antibody against both human and murine EphA2 (1C1) and the tubulin polymerization inhibitor, monomethylauristatin F (MMAF). Experimental design EphA2 expression was examined in endometrial cancer cell lines by Western Blot. Specificity of MEDI-547 was examined by antibody degradation and internalization assays. Viability and apoptosis were investigated in endometrial cancer cell lines and orthotopic tumor models. Results EphA2 was expressed in the Hec-1A and Ishikawa cells, but was absent in the SPEC-2 cells. Antibody degradation and internalization assays showed that the antibody drug conjugate decreased EphA2 protein levels and was internalized in EphA2 positive cells (Hec-1A and Ishikawa). Moreover, in vitro cytotoxicity and apoptosis assays demonstrated that the antibody drug conjugate decreased viability and increased apoptosis of Hec-1A and Ishikawa cells. In vivo therapy experiments in mouse orthotopic models with this antibody drug conjugate resulted in 86 to 88% growth inhibition (P < 0.001) in the orthotopic Hec-1A and Ishikawa models compared to controls. Moreover, the mice treated with this antibody drug conjugate had a lower incidence of distant metastasis compared with controls. The anti-tumor effects of the therapy were related to decreased proliferation and increased apoptosis of tumor and associated endothelial cells. Conclusions The preclinical data for endometrial cancer treatment using MEDI-547 demonstrate substantial anti-tumor activity. PMID:20388851

Anti-PD-1/PD-L1 antibody therapy for pretreated advanced nonsmall-cell lung cancer

PubMed Central

Zhou, Guo-Wu; Xiong, Ye; Chen, Si; Xia, Fan; Li, Qiang; Hu, Jia

2016-01-01

Abstract Background: Anti-PD-1/PD-L1 antibody therapy is a promising clinical treatment for nonsmall-cell lung cancer (NSCLC). However, whether anti-PD-1/PD-L1 antibody therapy can provide added benefits for heavily pretreated patients with advanced NSCLC and whether the efficacy of anti-PD-1/PD-L1 antibody therapy relates to the tumor PD-L1 expression level remain controversial. Thus, this meta-analysis evaluated the efficacy and safety of anti-PD-1/PD-L1 antibody therapy for pretreated patients with advanced NSCLC. Methods: Randomized clinical trials were retrieved by searching the PubMed, EMBASE, ASCO meeting abstract, clinicaltrial.gov, and Cochrane library databases. The pooled hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS), and odds ratios for the overall response rate and adverse events (AEs) were calculated by STATA software. Results: Three randomized clinical trials involving 1141 pretreated patients with advanced NSCLC were included. These trials all compared the efficacy and safety of anti-PD-1/PD-L1 antibodies (nivolumab and MPDL3280A) with docetaxel. The results suggested that, for all patients, anti-PD-1/PD-L1 therapy could acquire a greater overall response (odds ratio = 1.50, 95% CI: 1.08–2.07, P = 0.015, P for heterogeneity [Ph] = 0.620) and longer OS (HR = 0.71, 95% CI: 0.61–0.81, P < 0.001, Ph = 0.361) than docetaxel, but not PFS (HR = 0.83, 95% CI: 0.65–1.06, P = 0.134; Ph = 0.031). Subgroup analyses according to the tumor PD-L1 expression level showed that anti-PD-1/PD-L1 therapy could significantly improve both OS and PFS in patients with high expressions of PD-L1, but not in those with low expressions. Generally, the rates of grade 3 or 4 AEs of anti-PD-1/PD-L1 therapy were significantly lower than that of docetaxel. However, the risks of pneumonitis and hypothyroidism were significantly higher. Conclusion: Anti-PD-1/PD-L1 antibody therapy may significantly improve

Intracellular and non-neuronal targets of voltage-gated potassium channel complex antibodies.

PubMed

Lang, Bethan; Makuch, Mateusz; Moloney, Teresa; Dettmann, Inga; Mindorf, Swantje; Probst, Christian; Stoecker, Winfried; Buckley, Camilla; Newton, Charles R; Leite, M Isabel; Maddison, Paul; Komorowski, Lars; Adcock, Jane; Vincent, Angela; Waters, Patrick; Irani, Sarosh R

2017-04-01

Autoantibodies against the extracellular domains of the voltage-gated potassium channel (VGKC) complex proteins, leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein-2 (CASPR2), are found in patients with limbic encephalitis, faciobrachial dystonic seizures, Morvan's syndrome and neuromyotonia. However, in routine testing, VGKC complex antibodies without LGI1 or CASPR2 reactivities (double-negative) are more common than LGI1 or CASPR2 specificities. Therefore, the target(s) and clinical associations of double-negative antibodies need to be determined. Sera (n=1131) from several clinically defined cohorts were tested for IgG radioimmunoprecipitation of radioiodinated α-dendrotoxin ( 125 I-αDTX)-labelled VGKC complexes from mammalian brain extracts. Positive samples were systematically tested for live hippocampal neuron reactivity, IgG precipitation of 125 I-αDTX and 125 I-αDTX-labelled Kv1 subunits, and by cell-based assays which expressed Kv1 subunits, LGI1 and CASPR2. VGKC complex antibodies were found in 162 of 1131 (14%) sera. 90 of these (56%) had antibodies targeting the extracellular domains of LGI1 or CASPR2. Of the remaining 72 double-negative sera, 10 (14%) immunoprecipitated 125 I-αDTX itself, and 27 (38%) bound to solubilised co-expressed Kv1.1/1.2/1.6 subunits and/or Kv1.2 subunits alone, at levels proportionate to VGKC complex antibody levels (r=0.57, p=0.0017). The sera with LGI1 and CASPR2 antibodies immunoprecipitated neither preparation. None of the 27 Kv1-precipitating samples bound live hippocampal neurons or Kv1 extracellular domains, but 16 (59%) bound to permeabilised Kv1-expressing human embryonic kidney 293T cells. These intracellular Kv1 antibodies mainly associated with non-immune disease aetiologies, poor longitudinal clinical-serological correlations and a limited immunotherapy response. Double-negative VGKC complex antibodies are often directed against cytosolic epitopes of Kv1 subunits and occasionally against

Fully Human Antibodies and Antibody Drug Conjugates Targeting CD276 (B7-H3) for the Treatment of Cancer | NCI Technology Transfer Center | TTC

Cancer.gov

Researchers at the National Cancer Institute (NCI) seek research collaborations or licensees for a monoclonal antibody targeting CD276, also known as B7-H3, and related conjugates. The antibody and antibody drug conjugates (ADC) containing the antibody of the current invention were tested in vivo and have potential for use in cancer immunotherapy.

New targeted therapies in pancreatic cancer.

PubMed

Seicean, Andrada; Petrusel, Livia; Seicean, Radu

2015-05-28

Patients with pancreatic cancer have a poor prognosis with a median survival of 4-6 mo and a 5-year survival of less than 5%. Despite therapy with gemcitabine, patient survival does not exceed 6 mo, likely due to natural resistance to gemcitabine. Therefore, it is hoped that more favorable results can be obtained by using guided immunotherapy against molecular targets. This review summarizes the new leading targeted therapies in pancreatic cancers, focusing on passive and specific immunotherapies. Passive immunotherapy may have a role for treatment in combination with radiochemotherapy, which otherwise destroys the immune system along with tumor cells. It includes mainly therapies targeting against kinases, including epidermal growth factor receptor, Ras/Raf/mitogen-activated protein kinase cascade, human epidermal growth factor receptor 2, insulin growth factor-1 receptor, phosphoinositide 3-kinase/Akt/mTOR and hepatocyte growth factor receptor. Therapies against DNA repair genes, histone deacetylases, microRNA, and pancreatic tumor tissue stromal elements (stromal extracellular matric and stromal pathways) are also discussed. Specific immunotherapies, such as vaccines (whole cell recombinant, peptide, and dendritic cell vaccines), adoptive cell therapy and immunotherapy targeting tumor stem cells, have the role of activating antitumor immune responses. In the future, treatments will likely include personalized medicine, tailored for numerous molecular therapeutic targets of multiple pathogenetic pathways.

Beyond Antibodies as Binding Partners: The Role of Antibody Mimetics in Bioanalysis.

PubMed

Yu, Xiaowen; Yang, Yu-Ping; Dikici, Emre; Deo, Sapna K; Daunert, Sylvia

2017-06-12

The emergence of novel binding proteins or antibody mimetics capable of binding to ligand analytes in a manner analogous to that of the antigen-antibody interaction has spurred increased interest in the biotechnology and bioanalytical communities. The goal is to produce antibody mimetics designed to outperform antibodies with regard to binding affinities, cellular and tumor penetration, large-scale production, and temperature and pH stability. The generation of antibody mimetics with tailored characteristics involves the identification of a naturally occurring protein scaffold as a template that binds to a desired ligand. This scaffold is then engineered to create a superior binder by first creating a library that is then subjected to a series of selection steps. Antibody mimetics have been successfully used in the development of binding assays for the detection of analytes in biological samples, as well as in separation methods, cancer therapy, targeted drug delivery, and in vivo imaging. This review describes recent advances in the field of antibody mimetics and their applications in bioanalytical chemistry, specifically in diagnostics and other analytical methods.

Human tumor xenografts in mouse as a model for evaluating therapeutic efficacy of monoclonal antibodies or antibody-drug conjugate targeting receptor tyrosine kinases.

PubMed

Feng, Liang; Wang, Wei; Yao, Hang-Ping; Zhou, Jianwei; Zhang, Ruiwen; Wang, Ming-Hai

2015-01-01

Targeting receptor tyrosine kinases by therapeutic monoclonal antibodies and antibody-drug conjugates has met with tremendous success in clinical oncology. Currently, numerous therapeutic monoclonal antibodies are under preclinical development. The potential for moving candidate antibodies into clinical trials relies heavily on therapeutic efficacy validated by human tumor xenografts in mice. Here we describe methods used to determine therapeutic efficacy of monoclonal antibodies or antibody-drug conjugates specific to human receptor tyrosine kinase using human tumor xenografts in mice as the model. The end point of the study is to determine whether treatment of tumor-bearing mice with a monoclonal antibody or antibody-drug conjugates results in significant delay of tumor growth.

A graphene oxide based smart drug delivery system for tumor mitochondria-targeting photodynamic therapy

NASA Astrophysics Data System (ADS)

Wei, Yanchun; Zhou, Feifan; Zhang, Da; Chen, Qun; Xing, Da

2016-02-01

Subcellular organelles play critical roles in cell survival. In this work, a novel photodynamic therapy (PDT) drug delivery and phototoxicity on/off nano-system based on graphene oxide (NGO) as the carrier is developed to implement subcellular targeting and attacking. To construct the nanodrug (PPa-NGO-mAb), NGO is modified with the integrin αvβ3 monoclonal antibody (mAb) for tumor targeting. Pyropheophorbide-a (PPa) conjugated with polyethylene-glycol is used to cover the surface of the NGO to induce phototoxicity. Polyethylene-glycol phospholipid is loaded to enhance water solubility. The results show that the phototoxicity of PPa on NGO can be switched on and off in organic and aqueous environments, respectively. The PPa-NGO-mAb assembly is able to effectively target the αvβ3-positive tumor cells with surface ligand and receptor recognition; once endocytosized by the cells, they are observed escaping from lysosomes and subsequently transferring to the mitochondria. In the mitochondria, the `on' state PPa-NGO-mAb performs its effective phototoxicity to kill cells. The biological and physical dual selections and on/off control of PPa-NGO-mAb significantly enhance mitochondria-mediated apoptosis of PDT. This smart system offers a potential alternative to drug delivery systems for cancer therapy.Subcellular organelles play critical roles in cell survival. In this work, a novel photodynamic therapy (PDT) drug delivery and phototoxicity on/off nano-system based on graphene oxide (NGO) as the carrier is developed to implement subcellular targeting and attacking. To construct the nanodrug (PPa-NGO-mAb), NGO is modified with the integrin αvβ3 monoclonal antibody (mAb) for tumor targeting. Pyropheophorbide-a (PPa) conjugated with polyethylene-glycol is used to cover the surface of the NGO to induce phototoxicity. Polyethylene-glycol phospholipid is loaded to enhance water solubility. The results show that the phototoxicity of PPa on NGO can be switched on and off in

Nanotechnology-based drug delivery treatments and specific targeting therapy for age-related macular degeneration.

PubMed

Lin, Tai-Chi; Hung, Kuo-Hsuan; Peng, Chi-Hsien; Liu, Jorn-Hon; Woung, Lin-Chung; Tsai, Ching-Yao; Chen, Shih-Jen; Chen, Yan-Ting; Hsu, Chih-Chien

2015-11-01

Nanoparticles combined with cells, drugs, and specially designed genes provide improved therapeutic efficacy in studies and clinical setting, demonstrating a new era of treatment strategy, especially in retinal diseases. Nanotechnology-based drugs can provide an essential platform for sustaining, releasing and a specific targeting design to treat retinal diseases. Poly-lactic-co-glycolic acid is the most widely used biocompatible and biodegradable polymer approved by the Food and Drug Administration. Many studies have attempted to develop special devices for delivering small-molecule drugs, proteins, and other macromolecules consistently and slowly. In this article, we first review current progress in the treatment of age-related macular degeneration. Then, we discuss the function of vascular endothelial growth factor (VEGF) and the pharmacological effects of anti-VEGF-A antibodies and soluble or modified VEGF receptors. Lastly, we summarize the combination of antiangiogenic therapy and nanomedicines, and review current potential targeting therapy in age-related macular degeneration. Copyright © 2015. Published by Elsevier Taiwan.

Correlation between antibodies to bisphenol A, its target enzyme protein disulfide isomerase and antibodies to neuron‐specific antigens

PubMed Central

Vojdani, Aristo

2016-01-01

Abstract Evidence continues to increase linking autoimmunity and other complex diseases to the chemicals commonly found in our environment. Bisphenol A (BPA) is a synthetic monomer used widely in many forms, from food containers to toys, medical products and many others. The potential for BPA to participate as a triggering agent for autoimmune diseases is likely due to its known immunological influences. The goal of this research was to determine if immune reactivity to BPA has any correlation with neurological antibodies. BPA binds to a target enzyme called protein disulfide isomerase (PDI). Myelin basic protein (MBP) and myelin oligodendrocyte glycoprotein (MOG) are neuronal antigens that are target sites for neuroinflammation and neuroautoimmunity. We determined the co‐occurrence of anti‐MBP and anti‐MOG antibodies with antibodies made against BPA bound to human serum albumin in 100 healthy human subjects. Correlation between BPA to PDI, BPA to MOG, BPA to MBP, PDI to MBP and PDI to MOG were all highly statistically significant (P < 0.0001). The outcome of our study suggests that immune reactivity to BPA‐human serum albumin and PDI has a high degree of statistical significance with substantial correlation with both MBP and MOG antibody levels. This suggests that BPA may be a trigger for the production of antibodies against PDI, MBP and MOG. Immune reactivity to BPA bound to human tissue proteins may be a contributing factor to neurological autoimmune disorders. Further research is needed to determine the exact relationship of these antibodies with neuroautoimmunities. Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd. PMID:27610592

Anti-PDGF receptor β antibody-conjugated squarticles loaded with minoxidil for alopecia treatment by targeting hair follicles and dermal papilla cells.

PubMed

Aljuffali, Ibrahim A; Pan, Tai-Long; Sung, Calvin T; Chang, Shu-Hao; Fang, Jia-You

2015-08-01

This study developed lipid nanocarriers, called squarticles, conjugated with anti-platelet-derived growth factor (PDGF)-receptor β antibody to determine whether targeted Minoxidil (MXD) delivery to the follicles and dermal papilla cells (DPCs) could be achieved. Squalene and hexadecyl palmitate (HP) were used as the matrix of the squarticles. The PDGF-squarticles showed a mean diameter and zeta potential of 195 nm and -46 mV, respectively. Nanoparticle encapsulation enhanced MXD porcine skin deposition from 0.11 to 0.23 μg/mg. The antibody-conjugated nanoparticles ameliorated follicular uptake of MXD by 3-fold compared to that of the control solution in the in vivo mouse model. Both vertical and horizontal skin sections exhibited a wide distribution of nanoparticles in the follicles, epidermis, and deeper skin strata. The encapsulated MXD moderately elicited proliferation of DPCs and vascular endothelial growth factor (VEGF) expression. The active targeting of PDGF-squarticles may be advantageous to improving the limited success of alopecia therapy. Topical use of minoxidil is only one of the very few treatment options for alopecia. Nonetheless, the current delivery method is far from ideal. In this article, the authors developed lipid nanocarriers with anti-platelet-derived growth factor receptor ? antibody to target dermal papilla cells, and showed enhanced uptake of minoxidil. Copyright © 2015 Elsevier Inc. All rights reserved.

Emerging monoclonal antibodies for the treatment of renal cell carcinoma (RCC).

PubMed

Atkins, Michael B; Philips, George K

2016-09-01

Advanced renal cell carcinoma (RCC) was considered refractory to most cancer therapies until the 1980s, after which immune modulating agents and targeted agents were developed. Recently the rapid development of therapeutic monoclonal antibodies targeting immune checkpoint pathways has provided significant clinical benefit in patients with many distinct cancer types. Nivolumab, an anti-PD1 monoclonal antibody showed improvement in response rate and overall survival in patients with previously treated RCC and received US FDA approval in late 2015. Current efforts with anti-PD1-based therapy include combinations with ipilimumab and with VEGF pathway blockers in the hopes on building on the activity of single agent therapy. We describe our current understanding of tumor immunology including the basis of the tumor-specific immune response and the adaptive mechanisms used by the tumor for immune escape. We describe the mechanisms of action as well as the therapeutic application of the antibodies, ipilimumab, nivolumab and atezolizumab in patients with RCC. We identify key areas of active research in biomarker development and combination therapies. Clinical trials and the field of RCC therapeutics are expected to move in the direction of combination therapies using immune checkpoint inhibitors, extending overall survival as a benchmark for new drug approvals, and biomarker validation for improved selection of patients for specific therapies.

GABARAPL1 antibodies: target one protein, get one free!

PubMed

Le Grand, Jaclyn Nicole; Chakrama, Fatima Zahra; Seguin-Py, Stéphanie; Fraichard, Annick; Delage-Mourroux, Régis; Jouvenot, Michèle; Risold, Pierre-Yves; Boyer-Guittaut, Michaël

2011-11-01

Atg8 is a yeast protein involved in the autophagic process and in particular in the elongation of autophagosomes. In mammals, several orthologs have been identified and are classed into two subfamilies: the LC3 subfamily and the GABARAP subfamily, referred to simply as the LC3 or GABARAP families. GABARAPL1 (GABARAP-like protein 1), one of the proteins belonging to the GABARAP (GABA(A) receptor-associated protein) family, is highly expressed in the central nervous system and implicated in processes such as receptor and vesicle transport as well as autophagy. The proteins that make up the GABARAP family demonstrate conservation of their amino acid sequences and protein structures. In humans, GABARAPL1 shares 86% identity with GABARAP and 61% with GABARAPL2 (GATE-16). The identification of the individual proteins is thus very limited when working in vivo due to a lack of unique peptide sequences from which specific antibodies can be developed. Actually, and to our knowledge, there are no available antibodies on the market that are entirely specific to GABARAPL1 and the same may be true of the anti-GABARAP antibodies. In this study, we sought to examine the specificity of three antibodies targeted against different peptide sequences within GABARAPL1: CHEM-CENT (an antibody raised against a short peptide sequence within the center of the protein), PTG-NTER (an antibody raised against the N-terminus of the protein) and PTG-FL (an antibody raised against the full-length protein). The results described in this article demonstrate the importance of testing antibody specificity under the conditions for which it will be used experimentally, a caution that should be taken when studying the expression of the GABARAP family proteins.

Targeting of small molecule anticancer drugs to the tumour and its vasculature using cationic liposomes: lessons from gene therapy

PubMed Central

Dass, Crispin R; Choong, Peter FM

2006-01-01

Cationic (positively charged) liposomes have been tested in various gene therapy clinical trials for neoplastic and other diseases. They have demonstrated selectivity for tumour vascular endothelial cells raising hopes for both antiangiogenic and antivascular therapies. They are also capable of being selectively delivered to the lungs and liver when administered intravenously. These vesicles are being targeted to the tumour in various parts of the body by using advanced liposomal systems such as ligand-receptor and antibody-antigen combinations. At present, the transferrin receptor is commonly used for cancer-targeted drug delivery systems including cationic liposomes. This review looks at the growing utility of these vesicles for delivery of small molecule anticancer drugs. PMID:16792817

Monoclonal Antibody Fragments for Targeting Therapeutics to Growth Plate Cartilage | NCI Technology Transfer Center | TTC

Cancer.gov

Researchers at The Eunice Kennedy Shriver National Institute on Child Health and Human Development (NICHD) have discovered monoclonal antibodies that bind to matrilin-3, a protein specifically expressed in cartilage tissue, that could be used for treating or inhibiting growth plate disorders, such as a skeletal dysplasia or short stature. The monoclonal antibodies can also be used to target therapeutic agents, such as anti-arthritis agents, to cartilage tissue. NICHD seeks statements of capability or interest from parties interested in collaborative research to co-develop, evaluate, or commercialize treatment of skeletal disorders using targeting antibodies.

Antibody derivatization and conjugation strategies: application in preparation of stealth immunoliposome to target chemotherapeutics to tumor.

PubMed

Manjappa, Arehalli S; Chaudhari, Kiran R; Venkataraju, Makam P; Dantuluri, Prudhviraju; Nanda, Biswarup; Sidda, Chennakesavulu; Sawant, Krutika K; Murthy, Rayasa S Ramachandra

2011-02-28

A great deal of effort has been made over the years to develop liposomes that have targeting vectors (oligosaccharides, peptides, proteins and vitamins) attached to the bilayer surface. Most studies have focused on antibody conjugates since procedures for producing highly specific monoclonal antibodies are well established. Antibody conjugated liposomes have recently attracted a great deal of interest, principally because of their potential use as targeted drug delivery systems and in diagnostic applications. A number of methods have been reported for coupling antibodies to the surface of stealth liposomes. The objective of this review is to enumerate various strategies which are employed in the modification and conjugation of antibodies to the surface of stealth liposomes. This review also describes various derivatization techniques of lipids prior and after their use in the preparation of liposomes. The use of single chain variable fragments and affibodies as targeting ligands in the preparation of immunoliposomes is also discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

Ionizing radiation delivered by specific antibody is therapeutic against a fungal infection

PubMed Central

Dadachova, Ekaterina; Nakouzi, Antonio; Bryan, Ruth A.; Casadevall, Arturo

2003-01-01

There is an urgent need for new antimicrobial therapies to combat drug resistance, new pathogens, and the relative inefficacy of current therapy in compromised hosts. Ionizing radiation can kill microorganisms quickly and efficiently, but this modality has not been exploited as a therapeutic antimicrobial strategy. We have developed methods to target ionizing radiation to a fungal cell by labeling a specific mAb with the therapeutic radioisotopes Rhenium-188 and Bismuth-213. Radiolabeled antibody killed cells of human pathogenic fungus Cryptococcus neoformans in vitro, thus converting an antibody with no inherent antifungal activity into a microbicidal molecule. Administration of radiolabeled antibody to mice with C. neoformans infection delivered 213Bi and 188Re to the sites of infection, reduced their organ fungal burden, and significantly prolonged their survival without apparent toxicity. This study establishes the principle that targeted radiation can be used for the therapy of an infectious disease, and suggests that it may have wide applicability as an antimicrobial strategy. PMID:12930899

Ionizing radiation delivered by specific antibody is therapeutic against a fungal infection

NASA Astrophysics Data System (ADS)

Dadachova, Ekaterina; Nakouzi, Antonio; Bryan, Ruth A.; Casadevall, Arturo

2003-09-01

There is an urgent need for new antimicrobial therapies to combat drug resistance, new pathogens, and the relative inefficacy of current therapy in compromised hosts. Ionizing radiation can kill microorganisms quickly and efficiently, but this modality has not been exploited as a therapeutic antimicrobial strategy. We have developed methods to target ionizing radiation to a fungal cell by labeling a specific mAb with the therapeutic radioisotopes Rhenium-188 and Bismuth-213. Radiolabeled antibody killed cells of human pathogenic fungus Cryptococcus neoformans in vitro, thus converting an antibody with no inherent antifungal activity into a microbicidal molecule. Administration of radiolabeled antibody to mice with C. neoformans infection delivered 213Bi and 188Re to the sites of infection, reduced their organ fungal burden, and significantly prolonged their survival without apparent toxicity. This study establishes the principle that targeted radiation can be used for the therapy of an infectious disease, and suggests that it may have wide applicability as an antimicrobial strategy.

A33 antibody-functionalized exosomes for targeted delivery of doxorubicin against colorectal Cancer.

PubMed

Li, Yan; Gao, Yuan; Gong, Chunai; Wang, Zhuo; Xia, Qingming; Gu, Fenfen; Hu, Chuling; Zhang, Lijuan; Guo, Huiling; Gao, Shen

2018-06-20

Exosomes have emerged as a promising drug carrier with low immunogenicity, high biocompatibility and delivery efficiency. Here in, we isolated exosomes from A33-positive LIM1215 cells (A33-Exo) and loaded them with doxorubicin (Dox). Furthermore, we coated surface-carboxyl superparamagnetic iron oxide nanoparticles (US) with A33 antibodies (A33Ab-US), expecting that these A33 antibodies on the surface of the nanoparticles could bind to A33-positive exosomes and form a complex (A33Ab-US-Exo/Dox) to target A33-positive colon cancer cells. The results showed that A33Ab-US-Exo/Dox had good binding affinity and antiproliferative effect in LIM1215 cells, as shown by increased uptake of the complex. In vivo study showed that A33Ab-US-Exo/Dox had an excellent tumor targeting ability, and was able to inhibit tumor growth and prolong the survival of the mice with reduced cardiotoxicity. In summary, exosomes functionalized by targeting ligands through coating with high-density antibodies may prove to be a novel delivery system for targeted drugs against human cancers. Copyright © 2018 Elsevier Inc. All rights reserved.

Using antibody directed phototherapy to target oesophageal adenocarcinoma with heterogeneous HER2 expression

PubMed Central

Pye, Hayley; Butt, Mohammed Adil; Funnell, Laura; Reinert, Halla W.; Puccio, Ignazio; Rehman Khan, Saif U.; Saouros, Savvas; Marklew, Jared S.; Stamati, Ioanna; Qurashi, Maryam; Haidry, Rehan; Sehgal, Vinay; Oukrif, Dahmane; Gandy, Michael; Whitaker, Hayley C.; Rodriguez-Justo, Manuel; Novelli, Marco; Hamoudi, Rifat; Yahioglu, Gokhan; Deonarain, Mahendra P.; Lovat, Laurence B.

2018-01-01

Early oesophageal adenocarcinoma (OA) and pre-neoplastic dysplasia may be treated with endoscopic resection and ablative techniques such as photodynamic therapy (PDT). Though effective, discrete areas of disease may be missed leading to recurrence. PDT further suffers from the side effects of off-target photosensitivity. A tumour specific and light targeted therapeutic agent with optimised pharmacokinetics could be used to destroy residual cancerous cells left behind after resection. A small molecule antibody-photosensitizer conjugate was developed targeting human epidermal growth factor receptor 2 (HER2). This was tested in an in vivo mouse model of human OA using a xenograft flank model with clinically relevant low level HER2 expression and heterogeneity. In vitro we demonstrate selective binding of the conjugate to tumour versus normal tissue. Light dependent cytotoxicity of the phototherapy agent in vitro was observed. In an in vivo OA mouse xenograft model the phototherapy agent had desirable pharmacokinetic properties for tumour uptake and blood clearance time. PDT treatment caused tumour growth arrest in all the tumours despite the tumours having a clinically defined low/negative HER2 expression level. This new phototherapy agent shows therapeutic potential for treatment of both HER2 positive and borderline/negative OA. PMID:29796164

Elimination of established murine colon carcinoma metastases by antibody-interleukin 2 fusion protein therapy.

PubMed

Xiang, R; Lode, H N; Dolman, C S; Dreier, T; Varki, N M; Qian, X; Lo, K M; Lan, Y; Super, M; Gillies, S D; Reisfeld, R A

1997-11-01

A recombinant humanized antibody-interleukin 2 fusion protein (huKS1/4-IL-2) was used to direct IL-2 to the tumor microenvironment and elicit a T cell-mediated eradication of established pulmonary and hepatic CT26-KSA colon carcinoma metastases in syngeneic BALB/c mice. This antitumor effect was specific because a fusion protein, which was nonreactive with these tumor cells, failed to exert any such effect. The efficacy of the huKS1/4-IL-2 fusion protein in eliminating metastases was documented because mixtures of monoclonal antibody huKS1/4 with recombinant human IL-2 were ineffective and, at best, only partially reduced tumor load. Two lines of evidence indicated the eradication of metastases and the absence of minimal residual disease in animals treated with the fusion protein: first, the lack of detection of CT26-KSA cells by reverse transcription-PCR, which can detect one tumor cell in 10(6) liver cells; and second, the tripling of life span. The effector mechanism involved in this tumor eradication is dependent on T cells because the IL-2-directed therapy is ineffective in T cell-deficient SCID mice. The essential effector cells were further characterized as CD8+ T cells by in vivo depletion studies. Such T cells, isolated from tumor-bearing mice after fusion protein therapy, elicited MHC class I-restricted cytotoxicity in vitro against colon carcinoma target cells. Taken together, these data indicate that fusion protein-directed IL-2 therapy induces a T cell-dependent host immune response capable of eradicating established colon cancer metastases in an animal tumor model.

The EGF receptor family as targets for cancer therapy.

PubMed

Mendelsohn, J; Baselga, J

2000-12-27

Human carcinomas frequently express high levels of receptors in the EGF receptor family, and overexpression of at least two of these receptors, the EGF receptor (EGFr) and closely related ErbB2, has been associated with a more aggressive clinical behavior. Further, transfection or activation of high levels of these two receptors in nonmalignant cell lines can lead to a transformed phenotype. For these reasons therapies directed at preventing the function of these receptors have the potential to be useful anti-cancer treatments. In the last two decades monoclonal antibodies (MAbs) which block activation of the EGFr and ErbB2 have been developed. These MAbs have shown promising preclinical activity and 'chimeric' and 'humanized' MAbs have been produced in order to obviate the problem of host immune reactions. Clinical activity with these antibodies has been documented: trastuzumab, a humanized anti-ErbB2 MAb, is active and was recently approved in combination with paclitaxel for the therapy of patients with metastatic ErbB2-overexpressing breast cancer; IMC-C225, a chimeric anti-EGFr MAb, has shown impressive activity when combined with radiation therapy and reverses resistance to chemotherapy. In addition to antibodies, compounds that directly inhibit receptor tyrosine kinases have shown preclinical activity and early clinical activity has been reported. A series of phase III studies with these antibodies and direct tyrosine kinase inhibitors are ongoing or planned, and will further address the role of these active anti-receptor agents in the treatment of patients with cancer.

Development of a Function-Blocking Antibody Against Fibulin-3 as a Targeted Reagent for Glioblastoma.

PubMed

Nandhu, Mohan S; Behera, Prajna; Bhaskaran, Vivek; Longo, Sharon L; Barrera-Arenas, Lina M; Sengupta, Sadhak; Rodriguez-Gil, Diego J; Chiocca, E Antonio; Viapiano, Mariano S

2018-02-15

Purpose: We sought a novel approach against glioblastomas (GBM) focused on targeting signaling molecules localized in the tumor extracellular matrix (ECM). We investigated fibulin-3, a glycoprotein that forms the ECM scaffold of GBMs and promotes tumor progression by driving Notch and NFκB signaling. Experimental Design: We used deletion constructs to identify a key signaling motif of fibulin-3. An mAb (mAb428.2) was generated against this epitope and extensively validated for specific detection of human fibulin-3. mAb428.2 was tested in cultures to measure its inhibitory effect on fibulin-3 signaling. Nude mice carrying subcutaneous and intracranial GBM xenografts were treated with the maximum achievable dose of mAb428.2 to measure target engagement and antitumor efficacy. Results: We identified a critical 23-amino acid sequence of fibulin-3 that activates its signaling mechanisms. mAb428.2 binds to that epitope with nanomolar affinity and blocks the ability of fibulin-3 to activate ADAM17, Notch, and NFκB signaling in GBM cells. mAb428.2 treatment of subcutaneous GBM xenografts inhibited fibulin-3, increased tumor cell apoptosis, and enhanced the infiltration of inflammatory macrophages. The antibody reduced tumor growth and extended survival of mice carrying GBMs as well as other fibulin-3-expressing tumors. Locally infused mAb428.2 showed efficacy against intracranial GBMs, increasing tumor apoptosis and reducing tumor invasion and vascularization, which are enhanced by fibulin-3. Conclusions: To our knowledge, this is the first rationally developed, function-blocking antibody against an ECM target in GBM. Our results offer a proof of principle for using "anti-ECM" strategies toward more efficient targeted therapies for malignant glioma. Clin Cancer Res; 24(4); 821-33. ©2017 AACR . ©2017 American Association for Cancer Research.

Advanced targeted therapies in cancer: Drug nanocarriers, the future of chemotherapy.

PubMed

Pérez-Herrero, Edgar; Fernández-Medarde, Alberto

2015-06-01

Cancer is the second worldwide cause of death, exceeded only by cardiovascular diseases. It is characterized by uncontrolled cell proliferation and an absence of cell death that, except for hematological cancers, generates an abnormal cell mass or tumor. This primary tumor grows thanks to new vascularization and, in time, acquires metastatic potential and spreads to other body sites, which causes metastasis and finally death. Cancer is caused by damage or mutations in the genetic material of the cells due to environmental or inherited factors. While surgery and radiotherapy are the primary treatment used for local and non-metastatic cancers, anti-cancer drugs (chemotherapy, hormone and biological therapies) are the choice currently used in metastatic cancers. Chemotherapy is based on the inhibition of the division of rapidly growing cells, which is a characteristic of the cancerous cells, but unfortunately, it also affects normal cells with fast proliferation rates, such as the hair follicles, bone marrow and gastrointestinal tract cells, generating the characteristic side effects of chemotherapy. The indiscriminate destruction of normal cells, the toxicity of conventional chemotherapeutic drugs, as well as the development of multidrug resistance, support the need to find new effective targeted treatments based on the changes in the molecular biology of the tumor cells. These novel targeted therapies, of increasing interest as evidenced by FDA-approved targeted cancer drugs in recent years, block biologic transduction pathways and/or specific cancer proteins to induce the death of cancer cells by means of apoptosis and stimulation of the immune system, or specifically deliver chemotherapeutic agents to cancer cells, minimizing the undesirable side effects. Although targeted therapies can be achieved directly by altering specific cell signaling by means of monoclonal antibodies or small molecules inhibitors, this review focuses on indirect targeted approaches that

B-cell-targeted therapies in systemic lupus erythematosus and ANCA-associated vasculitis: current progress.

PubMed

Md Yusof, Md Yuzaiful; Vital, Edward M J; Emery, Paul

2013-08-01

B cells play a central role in the pathogenesis of systemic lupus erythematosus and anti-neutrophil cytoplasmic antibody-associated vasculitis. There are various strategies for targeting B cells including depletion, inhibition of survival factors, activation and inhibition of co-stimulatory molecules. Controlled trials in systemic lupus erythematosus have shown positive results for belimumab, promising results for epratuzumab and negative results for rituximab. The failure of rituximab in controlled trials has been attributed to trial design, sample size and outcome measures rather than true inefficacy. In anti-neutrophil cytoplasmic antibody-associated vasculitis, rituximab is effective for remission induction and in relapsing disease. However, the optimal long-term re-treatment strategy remains to be determined. Over the next 5 years, evidence will be available regarding the clinical efficacy of these novel therapies, biomarkers and their long-term safety.

Single-Domain Antibodies and the Promise of Modular Targeting in Cancer Imaging and Treatment

PubMed Central

Iezzi, María Elena; Policastro, Lucía; Werbajh, Santiago; Podhajcer, Osvaldo; Canziani, Gabriela Alicia

2018-01-01

Monoclonal antibodies and their fragments have significantly changed the outcome of cancer in the clinic, effectively inhibiting tumor cell proliferation, triggering antibody-dependent immune effector cell activation and complement mediated cell death. Along with a continued expansion in number, diversity, and complexity of validated tumor targets there is an increasing focus on engineering recombinant antibody fragments for lead development. Single-domain antibodies (sdAbs), in particular those engineered from the variable heavy-chain fragment (VHH gene) found in Camelidae heavy-chain antibodies (or IgG2 and IgG3), are the smallest fragments that retain the full antigen-binding capacity of the antibody with advantageous properties as drugs. For similar reasons, growing attention is being paid to the yet smaller variable heavy chain new antigen receptor (VNAR) fragments found in Squalidae. sdAbs have been selected, mostly from immune VHH libraries, to inhibit or modulate enzyme activity, bind soluble factors, internalize cell membrane receptors, or block cytoplasmic targets. This succinct review is a compilation of recent data documenting the application of engineered, recombinant sdAb in the clinic as epitope recognition “modules” to build monomeric, dimeric and multimeric ligands that target, tag and stall solid tumor growth in vivo. Size, affinity, specificity, and the development profile of sdAbs drugs are seemingly consistent with desirable clinical efficacy and safety requirements. But the hepatotoxicity of the tetrameric anti-DR5-VHH drug in patients with pre-existing anti-drug antibodies halted the phase I clinical trial and called for a thorough pre-screening of the immune and poly-specific reactivities of the sdAb leads. PMID:29520274

Single-Domain Antibodies and the Promise of Modular Targeting in Cancer Imaging and Treatment.

PubMed

Iezzi, María Elena; Policastro, Lucía; Werbajh, Santiago; Podhajcer, Osvaldo; Canziani, Gabriela Alicia

2018-01-01

Monoclonal antibodies and their fragments have significantly changed the outcome of cancer in the clinic, effectively inhibiting tumor cell proliferation, triggering antibody-dependent immune effector cell activation and complement mediated cell death. Along with a continued expansion in number, diversity, and complexity of validated tumor targets there is an increasing focus on engineering recombinant antibody fragments for lead development. Single-domain antibodies (sdAbs), in particular those engineered from the variable heavy-chain fragment (VHH gene) found in Camelidae heavy-chain antibodies (or IgG2 and IgG3), are the smallest fragments that retain the full antigen-binding capacity of the antibody with advantageous properties as drugs. For similar reasons, growing attention is being paid to the yet smaller variable heavy chain new antigen receptor (VNAR) fragments found in Squalidae. sdAbs have been selected, mostly from immune VHH libraries, to inhibit or modulate enzyme activity, bind soluble factors, internalize cell membrane receptors, or block cytoplasmic targets. This succinct review is a compilation of recent data documenting the application of engineered, recombinant sdAb in the clinic as epitope recognition "modules" to build monomeric, dimeric and multimeric ligands that target, tag and stall solid tumor growth in vivo . Size, affinity, specificity, and the development profile of sdAbs drugs are seemingly consistent with desirable clinical efficacy and safety requirements. But the hepatotoxicity of the tetrameric anti-DR5-VHH drug in patients with pre-existing anti-drug antibodies halted the phase I clinical trial and called for a thorough pre-screening of the immune and poly-specific reactivities of the sdAb leads.

Site-targeted mutagenesis for stabilization of recombinant monoclonal antibody expressed in tobacco (Nicotiana tabacum) plants

PubMed Central

Hehle, Verena K.; Paul, Matthew J.; Roberts, Victoria A.; van Dolleweerd, Craig J.; Ma, Julian K.-C.

2016-01-01

This study examined the degradation pattern of a murine IgG1κ monoclonal antibody expressed in and extracted from transformed Nicotiana tabacum. Gel electrophoresis of leaf extracts revealed a consistent pattern of recombinant immunoglobulin bands, including intact and full-length antibody, as well as smaller antibody fragments. N-terminal sequencing revealed these smaller fragments to be proteolytic cleavage products and identified a limited number of protease-sensitive sites in the antibody light and heavy chain sequences. No strictly conserved target sequence was evident, although the peptide bonds that were susceptible to proteolysis were predominantly and consistently located within or near to the interdomain or solvent-exposed regions in the antibody structure. Amino acids surrounding identified cleavage sites were mutated in an attempt to increase resistance. Different Guy’s 13 antibody heavy and light chain mutant combinations were expressed transiently in N. tabacum and demonstrated intensity shifts in the fragmentation pattern, resulting in alterations to the full-length antibody-to-fragment ratio. The work strengthens the understanding of proteolytic cleavage of antibodies expressed in plants and presents a novel approach to stabilize full-length antibody by site-directed mutagenesis.—Hehle, V. K., Paul, M. J., Roberts, V. A., van Dolleweerd, C. J., Ma, J. K.-C. Site-targeted mutagenesis for stabilization of recombinant monoclonal antibody expressed in tobacco (Nicotiana tabacum) plants. PMID:26712217

Chimeric Antigen Receptor Therapy for Cancer

PubMed Central

Barrett, David M.; Singh, Nathan; Porter, David L.; Grupp, Stephan A.; June, Carl H.

2014-01-01

Improved outcomes for patients with cancer hinge on the development of new targeted therapies with acceptable short-term and long-term toxicity. Progress in basic, preclinical, and clinical arenas spanning cellular immunology, synthetic biology, and cell-processing technologies has paved the way for clinical applications of chimeric antigen receptor– based therapies. This new form of targeted immunotherapy merges the exquisite targeting specificity of monoclonal antibodies with the potent cytotoxicity and long-term persistence provided by cytotoxic T cells. Although this field is still in its infancy, clinical trials have already shown clinically significant antitumor activity in neuroblastoma, chronic lymphocytic leukemia, and B cell lymphoma, and trials targeting a variety of other adult and pediatric malignancies are under way. Ongoing work is focused on identifying optimal tumor targets and on elucidating and manipulating both cell- and host-associated factors to support expansion and persistence of the genetically engineered cells in vivo. The potential to target essentially any tumor-associated cell-surface antigen for which a monoclonal antibody can be made opens up an entirely new arena for targeted therapy of cancer. PMID:24274181

Approaches to target IgE antibodies in allergic diseases.

PubMed

Balbino, Bianca; Conde, Eva; Marichal, Thomas; Starkl, Philipp; Reber, Laurent L

2018-06-15

IgE is the antibody isotype found at the lowest concentration in the circulation. However IgE can undeniably play an important role in mediating allergic reactions; best exemplified by the clinical benefits of anti-IgE monoclonal antibody (omalizumab) therapy for some allergic diseases. This review will describe our current understanding of the interactions between IgE and its main receptors FcεRI and CD23 (FcεRII). We will review the known and potential functions of IgE in health and disease: in particular, its detrimental roles in allergic diseases and chronic spontaneous urticaria, and its protective functions in host defense against parasites and venoms. Finally, we will present an overview of the drugs that are in clinical development or have therapeutic potential for IgE-mediated allergic diseases. Copyright © 2018. Published by Elsevier Inc.

Manipulation of the Glycan-Specific Natural Antibody Repertoire for Immunotherapy

PubMed Central

New, J. Stewart; King, R. Glenn; Kearney, John F.

2015-01-01

Summary Natural immunoglobulin derived from innate-like B lymphocytes plays important roles in the suppression of inflammatory responses and represents a promising therapeutic target in a growing number of allergic and autoimmune diseases. These antibodies are commonly autoreactive and incorporate evolutionarily conserved specificities, including certain glycan-specific antibodies. Despite this conservation, exposure to bacterial polysaccharides during innate-like B lymphocyte development, through either natural exposure or immunization, induces significant changes in clonal representation within the glycan-reactive B cell pool. Glycan-reactive natural antibodies have been reported to play protective and pathogenic roles in autoimmune and inflammatory diseases. An understanding of the composition and functions of a healthy glycan-reactive natural antibody repertoire is therefore paramount. A more thorough understanding of natural antibody repertoire development holds promise for the design of both biological diagnostics and therapies. In this article we review the development and functions of natural antibodies and examine three glycan specificities, represented in the innate-like B cell pool, to illustrate the complex roles environmental antigens play in natural antibody repertoire development. We also discuss the implications of increased clonal plasticity of the innate-like B cell repertoire during neonatal and perinatal periods, and the prospect of targeting B cell development with interventional therapies and correct defects in this important arm of the adaptive immune system. PMID:26864103

Rapid Immunochromatographic Detection of Serum Anti-α-Galactosidase A Antibodies in Fabry Patients after Enzyme Replacement Therapy.

PubMed

Nakano, Sachie; Tsukimura, Takahiro; Togawa, Tadayasu; Ohashi, Toya; Kobayashi, Masahisa; Takayama, Katsuyoshi; Kobayashi, Yukuharu; Abiko, Hiroshi; Satou, Masatsugu; Nakahata, Tohru; Warnock, David G; Sakuraba, Hitoshi; Shibasaki, Futoshi

2015-01-01

We developed an immunochromatography-based assay for detecting antibodies against recombinant α-galactosidase A proteins in serum. The evaluation of 29 serum samples from Fabry patients, who had received enzyme replacement therapy with agalsidase alpha and/or agalsidase beta, was performed by means of this assay method, and the results clearly revealed that the patients exhibited the same level of antibodies against both agalsidase alpha and agalsidase beta, regardless of the species of recombinant α-galactosidase A used for enzyme replacement therapy. A conventional enzyme-linked immunosorbent assay supported the results. Considering these, enzyme replacement therapy with agalsidase alpha or agalsidase beta would generate antibodies against the common epitopes in both agalsidase alpha and agalsidase beta. Most of the patients who showed immunopositive reaction exhibited classic Fabry phenotype and harbored gene mutations affecting biosynthesis of α-galactosidase A. As immunochromatography is a handy and simple assay system which can be available at bedside, this assay method would be extremely useful for quick evaluation or first screening of serum antibodies against agalsidase alpha or agalsidase beta in Fabry disease with enzyme replacement therapy.

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

PubMed

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

2015-07-15

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

Targeted therapy in lung cancer: IPASS and beyond, keeping abreast of the explosion of targeted therapies for lung cancer

PubMed Central

Savas, Peter; Hughes, Brett

2013-01-01

Advances in the treatment of non-small cell lung cancer (NSCLC) over the last decade have predominantly involved the development of therapies directed at molecular targets such as mutations in the epidermal growth factor receptor (EGFR) or rearrangements in the anaplastic lymphoma kinase (ALK) gene. Other targets have been discovered at low frequency, with multiple agents approved or in development for treatment of these rare molecular subtypes. The tumour microenvironment has also provided opportunities for therapies targeting angiogenesis and the host immune response. This review will provide an overview of current targeted therapies in NSCLC and promising treatment approaches on the horizon. PMID:24163750

Surface functionalization of PLGA nanoparticles by non-covalent insertion of a homo-bifunctional spacer for active targeting in cancer therapy.

PubMed

Thamake, S I; Raut, S L; Ranjan, A P; Gryczynski, Z; Vishwanatha, J K

2011-01-21

This work reports the surface functionalization of polymeric PLGA nanoparticles by non-covalent insertion of a homo-bifunctional chemical crosslinker, bis(sulfosuccinimidyl) suberate (BS3) for targeted cancer therapy. We dissolved BS3 in aqueous solution of PVA during formulation of nanoparticles by a modified solid/oil/water emulsion solvent evaporation method. The non-covalent insertion of BS3 was confirmed by Fourier transform infrared (FTIR) spectroscopy. Curcumin and annexin A2 were used as a model drug and a cell specific target, respectively. Nanoparticles were characterized for particle size, zeta potential and surface morphology. The qualitative assessment of antibody attachment was performed by transmission electron microscopy (TEM) as well as confocal microscopy. The optimized formulation showed antibody attachment of 86%. However, antibody attachment was abolished upon blocking the functional groups of BS3. The availability of functional antibodies was evaluated by the presence of a light chain fraction after gel electrophoresis. We further evaluated the in vitro release kinetics of curcumin from antibody coated and uncoated nanoparticles. The release of curcumin is enhanced upon antibody attachment and followed an anomalous release pattern. We also observed that the cellular uptake of nanoparticles was significantly higher in annexin A2 positive cells than in negative cells. Therefore, these results demonstrate the potential use of this method for functionalization as well as to deliver chemotherapeutic agents for treating cancer.

Surface functionalization of PLGA nanoparticles by non-covalent insertion of a homo-bifunctional spacer for active targeting in cancer therapy

NASA Astrophysics Data System (ADS)

Thamake, S. I.; Raut, S. L.; Ranjan, A. P.; Gryczynski, Z.; Vishwanatha, J. K.

2011-01-01

This work reports the surface functionalization of polymeric PLGA nanoparticles by non-covalent insertion of a homo-bifunctional chemical crosslinker, bis(sulfosuccinimidyl) suberate (BS3) for targeted cancer therapy. We dissolved BS3 in aqueous solution of PVA during formulation of nanoparticles by a modified solid/oil/water emulsion solvent evaporation method. The non-covalent insertion of BS3 was confirmed by Fourier transform infrared (FTIR) spectroscopy. Curcumin and annexin A2 were used as a model drug and a cell specific target, respectively. Nanoparticles were characterized for particle size, zeta potential and surface morphology. The qualitative assessment of antibody attachment was performed by transmission electron microscopy (TEM) as well as confocal microscopy. The optimized formulation showed antibody attachment of 86%. However, antibody attachment was abolished upon blocking the functional groups of BS3. The availability of functional antibodies was evaluated by the presence of a light chain fraction after gel electrophoresis. We further evaluated the in vitro release kinetics of curcumin from antibody coated and uncoated nanoparticles. The release of curcumin is enhanced upon antibody attachment and followed an anomalous release pattern. We also observed that the cellular uptake of nanoparticles was significantly higher in annexin A2 positive cells than in negative cells. Therefore, these results demonstrate the potential use of this method for functionalization as well as to deliver chemotherapeutic agents for treating cancer.

Noninvasive, targeted gene therapy for acute spinal cord injury using LIFU-mediated BDNF-loaded cationic nanobubble destruction.

PubMed

Song, Zhaojun; Ye, Yongjie; Zhang, Zhi; Shen, Jieliang; Hu, Zhenming; Wang, Zhigang; Zheng, Jiazhuang

2018-02-12

Various gene delivery systems have been widely studied for the acute spinal cord injury (SCI) treatment. In the present study, a novel type of brain-derived neurotrophic factor (BDNF)-loaded cationic nanobubbles (CNBs) conjugated with MAP-2 antibody (mAb MAP-2 /BDNF/CNBs) was prepared to provide low-intensity focused ultrasound (LIFU)-targeted gene therapy. In vitro experiments, the ultrasound-targeted tranfection to BDNF overexpressioin in neurons and efficiently inhibition neuronal apoptosis have been demonstrated, and the elaborately designed mAb MAP-2 /BDNF/CNBs can specifically target to the neurons. Furthermore, in a acute SCI rat model, LIFU-mediated mAb MAP-2 /BDNF/CNBs transfection significantly increased BDNF expression, attenuated histological injury, decreased neurons loss, inhibited neuronal apoptosis in injured spinal cords, and increased BBB scores in SCI rats. LIFU-mediated mAb MAP-2 /BDNF/CNBs destruction significantly increase transfection efficiency of BDNF gene both in vitro and in vivo, and has a significant neuroprotective effect on the injured spinal cord. Therefore, the combination of LIFU irradiation and gene therapy through mAb MAP-2 /BDNF/CNBs can be considered as a novel non-invasive and targeted treatment for gene therapy of SCI. Copyright © 2018 Elsevier Inc. All rights reserved.

A novel method for measuring cellular antibody uptake using imaging flow cytometry reveals distinct uptake rates for two different monoclonal antibodies targeting L1.

PubMed

Hazin, John; Moldenhauer, Gerhard; Altevogt, Peter; Brady, Nathan R

2015-08-01

Monoclonal antibodies (mAbs) have emerged as a promising tool for cancer therapy. Differing approaches utilize mAbs to either deliver a drug to the tumor cells or to modulate the host's immune system to mediate tumor kill. The rate by which a therapeutic antibody is being internalized by tumor cells is a decisive feature for choosing the appropriate treatment strategy. We herein present a novel method to effectively quantitate antibody uptake of tumor cells by using image-based flow cytometry, which combines image analysis with high throughput of sample numbers and sample size. The use of this method is established by determining uptake rate of an anti-EpCAM antibody (HEA125), from single cell measurements of plasma membrane versus internalized antibody, in conjunction with inhibitors of endocytosis. The method is then applied to two mAbs (L1-9.3, L1-OV52.24) targeting the neural cell adhesion molecule L1 (L1CAM) at two different epitopes. Based on median cell population responses, we find that mAb L1-OV52.24 is rapidly internalized by the ovarian carcinoma cell line SKOV3ip while L1 mAb 9.3 is mainly retained at the cell surface. These findings suggest the L1 mAb OV52.24 as a candidate to be further developed for drug-delivery to cancer cells, while L1-9.3 may be optimized to tag the tumor cells and stimulate immunogenic cancer cell killing. Furthermore, when analyzing cell-to-cell variability, we observed L1 mAb OV52.24 rapidly transition into a subpopulation with high-internalization capacity. In summary, this novel high-content method for measuring antibody internalization rate provides a high level of accuracy and sensitivity for cell population measurements and reveals further biologically relevant information when taking into account cellular heterogeneity. Copyright © 2015 Elsevier B.V. All rights reserved.

Targeted Nanoparticles for Kidney Cancer Therapy

DTIC Science & Technology

2013-10-01

AD_________________ Award Number: W81XWH-10-1-0434 TITLE: Targeted Nanoparticles for Kidney Cancer Therapy PRINCIPAL...Targeted Nanoparticles for Kidney Cancer Therapy 5b. GRANT NUMBER W81XWH-10-1-0434 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...lines following treatment with D5 nanotubes. Tthermoablation will be studied initially. Human kidney cancer cells will be injected into the kidney

LnPO 4 Nanoparticles Doped with Ac-225 and Sequestered Daughters for Targeted Alpha Therapy

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

McLaughlin, Mark F.; Robertson, David; Pevsner, Paul H.

2014-02-01

For targeted alpha therapy (TAT) with 225Ac, daughter radioisotopes from the parent emissions should be controlled. We report on a second-generation layered nanoparticle (NP) with improved daughter retention that can mediate TAT of lung tumor colonies. NPs of La 3+, Gd 3+, and 225Ac 3+ ions were coated with additional layers of GdPO 4 and then coated with gold via citrate reduction of NaAuCl 4. MAb 201b, targeting thrombomodulin in lung endothelium, was added to a polyethylene glycol (dPEG)-COOH linker. Furthermore, we quantified the NPs:mAb ratio by labeling the mAb with 125I. NPs showed 30% injected dose/organ antibody-mediated uptake inmore » the lung, which increased to 47% in mice pretreated with clodronate liposomes to reduce phagocytosis. Retention of daughter 213Bi in lung tissue was more than 70% at one hour and about 90% at 24 hours postinjection. Treatment of mice with lung-targeted 225Ac NP reduced EMT-6 lung colonies relative to cold antibody competition for targeting or phosphate-buffered saline injected controls. Finally, we show that LnPO 4 NPs represent a viable solution to deliver the 225Ac as an in vivo α generator. The NPs successfully retain a large percentage of the daughter products without compromising the tumoricidal properties of the α-radiation.« less

Targeted nanosystems: Advances in targeted dendrimers for cancer therapy.

PubMed

Yang, Hu

2016-02-01

Dendrimers possess discrete highly compact nanostructures constituted of successive branched layers. Soon after the inception of dendrimers, recognition of their tunable structures and biologically favorable properties provoked a great enthusiasm in delving deeply into the utility of dendrimers for biomedical and pharmaceutical applications. One of the most important nanotechnology applications is the development of nanomedicines for targeted cancer therapies. Tremendous success in targeted therapies has been achieved with the use of dendrimer-based nanomedicines. This article provides a concise review on latest advances in the utility of dendrimers in immunotherapies and hormone therapies. Much basic and clinical research has been done since the invention of dendrimers, which are highly branched nano-sized molecules with the ability to act as carriers in nanomedicine. In this concise review article, the authors highlighted the current use of dendrimers in immunotherapies and hormone therapies in the fight against cancers. Copyright © 2015 Elsevier Inc. All rights reserved.

Reagent Target Request for Monoclonal Antibody Production and Characterization | Office of Cancer Clinical Proteomics Research

Cancer.gov

NCI's Antibody Characterization Program provides reagents and other critical resources to support protein/peptide measurements and analysis. In an effort to produce and distribute well-characterized monoclonal antibodies to the scientific community, the program is seeking cancer related protein targets for antibody production and characterization for distribution to the research community. Submission Period: May 20, 2011 - July 1, 2011.

NCI Requests Targets for Monoclonal Antibody Production and Characterization | Office of Cancer Clinical Proteomics Research

Cancer.gov

In an effort to provide well-characterized monoclonal antibodies to the scientific community, NCI's Antibody Characterization Program requests cancer-related protein targets for affinity production and distribution. Submissions will be accepted through July 9, 2012.

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

PubMed

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

2016-12-01

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

An update on the use of antibodies against the filoviruses

PubMed Central

Saphire, Erica Ollmann

2015-01-01

Multiple recent, independent studies have confirmed that passively administered antibodies can provide effective postexposure therapy in nonhuman primates after exposure to an otherwise lethal dose of Ebola virus or Marburg virus. In this article, we review composition and performance of the antibody cocktails tested thus far, what is known about antibody epitopes on the viral glycoprotein target and ongoing research questions in further development of such cocktails for pre-exposure or emergency postexposure use. PMID:24188676

β2-Microglobulin-mediated signaling as a target for cancer therapy.

PubMed

Nomura, Takeo; Huang, Wen-Chin; Zhau, Haiyen E; Josson, Sajni; Mimata, Hiromitsu; Chung, Leland W K

2014-03-01

β2-microglobulin (β2-m) has become the focus of intense scrutiny since the discovery of its undesirable roles promoting osteomimicry and cancer progression. β2-m is a well-known housekeeping protein that forms complexes with the heavy chain of major histocompatibility complex class I molecules, which are heterodimeric cell surface proteins that present antigenic peptides to cytotoxic T cells. On recognition of foreign peptide antigens on cell surfaces, T cells actively bind and lyse antigen-presenting cancer cells. In addition to its roles in tumor immunity, β2-m has two different functions in cancer cells, either tumor promoting or tumor suppressing, in cancer cell context-dependent manner. Our studies have demonstrated that β2-m is involved extensively in the functional regulation of growth, survival, apoptosis, and even metastasis of cancer cells. We found that β2-m is a soluble growth factor and a pleiotropic signaling molecule which interacts with its receptor, hemochromatosis protein, to modulate epithelial-to-mesenchymal transition (EMT) through iron-responsive pathways. Specific antibodies against β2-m have remarkable tumoricidal activity in cancer, through β2-m action on iron flux, alterations of intracellular reactive oxygen species, DNA damage and repair enzyme activities, β-catenin activation and cadherin switching, and tumor responsiveness to hypoxia. These novel functions of β2-m and β2-m signaling may be common to several solid tumors including human lung, breast, renal, and prostate cancers. Our experimental results could lead to the development of a novel class of antibody-based pharmaceutical agents for cancer growth control. In this review, we briefly summarize the recent data regarding β2-m as a promising new cancer therapeutic target and discuss antagonizing this therapeutic target with antibody therapy for the treatment of localized and disseminated cancers.

β2-Microglobulin-mediated Signaling as a Target for Cancer Therapy

PubMed Central

Nomura, Takeo; Huang, Wen-Chin; Zhau, Haiyen E.; Josson, Sajni; Mimata, Hiromitsu; Kaur, Mandeep

2014-01-01

β2-microglobulin (β2-m) has become the focus of intense scrutiny since the discovery of its undesirable roles promoting osteomimicry and cancer progression. β2-m is a well-known housekeeping protein that forms complexes with the heavy chain of major histocompatibility complex class I molecules, which are heterodimeric cell surface proteins that present antigenic peptides to cytotoxic T cells. On recognition of foreign peptide antigens on cell surfaces, T cells actively bind and lyse antigen-presenting cancer cells. In addition to its roles in tumor immunity, β2-m has two different functions in cancer cells, either tumor promoting or tumor suppressing, in cancer cell context-dependent manner. Our studies have demonstrated that β2-m is involved extensively in the functional regulation of growth, survival, apoptosis, and even metastasis of cancer cells. We found that β2-m is a soluble growth factor and a pleiotropic signaling molecule which interacts with its receptor, hemochromatosis protein, to modulate epithelial-to-mesenchymal transition (EMT) through iron-responsive pathways. Specific antibodies against β2-m have remarkable tumoricidal activity in cancer, through β2-m action on iron flux, alterations of intracellular reactive oxygen species, DNA damage and repair enzyme activities, β-catenin activation and cadherin switching, and tumor responsiveness to hypoxia. These novel functions of β2-m and β2-m signaling may be common to several solid tumors including human lung, breast, renal, and prostate cancers. Our experimental results could lead to the development of a novel class of antibody-based pharmaceutical agents for cancer growth control. In this review, we briefly summarize the recent data regarding β2-m as a promising new cancer therapeutic target and discuss antagonizing this therapeutic target with antibody therapy for the treatment of localized and disseminated cancers. PMID:23848204

Monoclonal Antibodies against the MET/HGF Receptor and Its Ligand: Multitask Tools with Applications from Basic Research to Therapy

PubMed Central

Prat, Maria; Oltolina, Francesca; Basilico, Cristina

2014-01-01

Monoclonal antibodies can be seen as valuable tools for many aspects of basic as well as applied sciences. In the case of MET/HGFR, they allowed the identification of truncated isoforms of the receptor, as well as the dissection of different epitopes, establishing structure–function relationships. Antibodies directed against MET extracellular domain were found to be full or partial receptor agonists or antagonists. The agonists can mimic the effects of the different isoforms of the natural ligand, but with the advantage of being more stable than the latter. Thus, some agonist antibodies promote all the biological responses triggered by MET activation, including motility, proliferation, morphogenesis, and protection from apoptosis, while others can induce only a migratory response. On the other hand, antagonists can inhibit MET-driven biological functions either by competing with the ligand or by removing the receptor from the cell surface. Since MET/HGFR is often over-expressed and/or aberrantly activated in tumors, monoclonal antibodies can be used as probes for MET detection or as “bullets” to target MET-expressing tumor cells, thus pointing to their use in diagnosis and therapy. PMID:28548076

Preclinical development of a bispecific antibody that safely and effectively targets CD19 and CD47 for the treatment of B cell lymphoma and leukemia.

PubMed

Buatois, Vanessa; Johnson, Zoë; Salgado-Pires, Susana; Papaïoannou, Anne; Hatterer, Eric; Chauchet, Xavier; Richard, Françoise; Barba, Leticia; Daubeuf, Bruno; Cons, Laura; Broyer, Lucile; D'Asaro, Matilde; Matthes, Thomas; LeGallou, Simon; Fest, Thierry; Tarte, Karin; Clarke Hinojosa, Robert K; Genescà Ferrer, Eulàlia; Ribera, José María; Dey, Aditi; Bailey, Katharine; Fielding, Adele K; Eissenberg, Linda; Ritchey, Julie; Rettig, Michael; DiPersio, John F; Kosco-Vilbois, Marie H; Masternak, Krzysztof; Fischer, Nicolas; Shang, Limin; Ferlin, Walter G

2018-05-09

CD47, a ubiquitously expressed innate immune checkpoint receptor that serves as a universal "don't eat me" signal of phagocytosis, is often up-regulated by hematological and solid cancers to evade immune surveillance. Development of CD47-targeted modalities is hindered by the ubiquitous expression of the target, often leading to rapid drug elimination and hemotoxicity including anemia. To overcome such liabilities, we have developed a fully human bispecific antibody, NI-1701, designed to co-engage CD47 and CD19 selectively on B cells. NI-1701 demonstrates favorable elimination kinetics with no deleterious effects seen on hematological parameters following single or multiple administrations to non-human primates. Potent in vitro and in vivo activity is induced by NI-1701 to kill cancer cells across a plethora of B cell malignancies and control tumor growth in xenograft mouse models. The mechanism affording maximal tumor growth inhibition by NI-1701 is dependent on the co-engagement of CD47/CD19 on B cells inducing potent antibody dependent cellular phagocytosis of the targeted cells. NI-1701-induced control of tumor growth in immunodeficient NOD/SCID mice was more effective than that achieved with the anti-CD20 targeted antibody, rituximab. Interestingly, a synergistic effect was seen when tumor-implanted mice were co-administered NI-1701 and rituximab leading to significantly improved tumor growth inhibition and regression in some animals. We describe herein, a novel bispecific antibody approach aimed at sensitizing B cells to become more readily phagocytosed and eliminated thus offering an alternative or adjunct therapeutic option to patients with B cell malignancies refractory/resistant to anti-CD20 targeted therapy. Copyright ©2018, American Association for Cancer Research.

Abeta targets of the biosimilar antibodies of Bapineuzumab, Crenezumab, Solanezumab in comparison to an antibody against N‑truncated Abeta in sporadic Alzheimer disease cases and mouse models.

PubMed

Bouter, Yvonne; Lopez Noguerola, Jose Socrates; Tucholla, Petra; Crespi, Gabriela A N; Parker, Michael W; Wiltfang, Jens; Miles, Luke A; Bayer, Thomas A

2015-11-01

Solanezumab and Crenezumab are two humanized antibodies targeting Amyloid-β (Aβ) which are currently tested in multiple clinical trials for the prevention of Alzheimer's disease. However, there is a scientific discussion ongoing about the target engagement of these antibodies. Here, we report the immunohistochemical staining profiles of biosimilar antibodies of Solanezumab, Crenezumab and Bapineuzumab in human formalin-fixed, paraffin-embedded tissue and human fresh frozen tissue. Furthermore, we performed a direct comparative immunohistochemistry analysis of the biosimilar versions of the humanized antibodies in different mouse models including 5XFAD, Tg4-42, TBA42, APP/PS1KI, 3xTg. The staining pattern with these humanized antibodies revealed a surprisingly similar profile. All three antibodies detected plaques, cerebral amyloid angiopathy and intraneuronal Aβ in a similar fashion. Remarkably, Solanezumab showed a strong binding affinity to plaques. We also reaffirmed that Bapineuzumab does not recognize N-truncated or modified Aβ, while Solanezumab and Crenezumab do detect N-terminally modified Aβ peptides Aβ4-42 and pyroglutamate Aβ3-42. In addition, we compared the results with the staining pattern of the mouse NT4X antibody that recognizes specifically Aβ4-42 and pyroglutamate Aβ3-42, but not full-length Aβ1-42. In contrast to the biosimilar antibodies of Solanezumab, Crenezumab and Bapineuzumab, the murine NT4X antibody shows a unique target engagement. NT4X does barely cross-react with amyloid plaques in human tissue. It does, however, detect cerebral amyloid angiopathy in human tissue. In Alzheimer mouse models, NT4X detects intraneuronal Aβ and plaques comparable to the humanized antibodies. In conclusion, the biosimilar antibodies Solanezumab, Crenezumab and Bapineuzumab strongly react with amyloid plaques, which are in contrast to the NT4X antibody that hardly recognizes plaques in human tissue. Therefore, NT4X is the first of a new class of

Antibody-cytokine fusion proteins for treatment of cancer: engineering cytokines for improved efficacy and safety.

PubMed

Young, Patricia A; Morrison, Sherie L; Timmerman, John M

2014-10-01

The true potential of cytokine therapies in cancer treatment is limited by the inability to deliver optimal concentrations into tumor sites due to dose-limiting systemic toxicities. To maximize the efficacy of cytokine therapy, recombinant antibody-cytokine fusion proteins have been constructed by a number of groups to harness the tumor-targeting ability of monoclonal antibodies. The aim is to guide cytokines specifically to tumor sites where they might stimulate more optimal anti-tumor immune responses while avoiding the systemic toxicities of free cytokine therapy. Antibody-cytokine fusion proteins containing interleukin (IL)-2, IL-12, IL-21, tumor necrosis factor (TNF)α, and interferons (IFNs) α, β, and γ have been constructed and have shown anti-tumor activity in preclinical and early-phase clinical studies. Future priorities for development of this technology include optimization of tumor targeting, bioactivity of the fused cytokine, and choice of appropriate agents for combination therapies. This review is intended to serve as a framework for engineering an ideal antibody-cytokine fusion protein, focusing on previously developed constructs and their clinical trial results. Copyright © 2014 Elsevier Inc. All rights reserved.

Synergistic anti-tumor therapy by a comb-like multifunctional antibody nanoarray with exceptionally potent activity

NASA Astrophysics Data System (ADS)

Li, Huafei; Sun, Yun; Chen, Di; Zhao, He; Zhao, Mengxin; Zhu, Xiandi; Ke, Changhong; Zhang, Ge; Jiang, Cheng; Zhang, Li; Zhang, Fulei; Wei, Huafeng; Li, Wei

2015-10-01

Simultaneously blocking multiple mediators offers new hope for the treatment of complex diseases. However, the curative potential of current combination therapy by chronological administration of separate monoclonal antibodies (mAbs) or multi-specific mAbs is still moderate due to inconvenient manipulation, low cooperative effectors, poor pharmacokinetics and insufficient tumor accumulation. Here, we describe a facile strategy that arms distinct mAbs with cooperative effectors onto a long chain to form a multicomponent comb-like nano mAb. Unlike dissociative parental mAbs, the multifunctional mAb nanoarray (PL-RB) constructed from type I/II anti-CD20 mAbs shows good pharmacokinetics. This PL-RB simultaneously targets distinct epitopes on a single antigen (Ag) and neighboring Ags on different lymphocytes. This unique intra- and intercellular Ag cross-linking endows the multifunctional mAb nanoarray with potent apoptosis activity. The exceptional apoptosis, complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC) that are synchronously evoked by the nano PL-RB are further synergistically promoted via enhanced permeability and retention (EPR), which resulted in high intratumor accumulation and excellent anti-lymphoma efficiency.

Synergistic anti-tumor therapy by a comb-like multifunctional antibody nanoarray with exceptionally potent activity.

PubMed

Li, Huafei; Sun, Yun; Chen, Di; Zhao, He; Zhao, Mengxin; Zhu, Xiandi; Ke, Changhong; Zhang, Ge; Jiang, Cheng; Zhang, Li; Zhang, Fulei; Wei, Huafeng; Li, Wei

2015-10-28

Simultaneously blocking multiple mediators offers new hope for the treatment of complex diseases. However, the curative potential of current combination therapy by chronological administration of separate monoclonal antibodies (mAbs) or multi-specific mAbs is still moderate due to inconvenient manipulation, low cooperative effectors, poor pharmacokinetics and insufficient tumor accumulation. Here, we describe a facile strategy that arms distinct mAbs with cooperative effectors onto a long chain to form a multicomponent comb-like nano mAb. Unlike dissociative parental mAbs, the multifunctional mAb nanoarray (PL-RB) constructed from type I/II anti-CD20 mAbs shows good pharmacokinetics. This PL-RB simultaneously targets distinct epitopes on a single antigen (Ag) and neighboring Ags on different lymphocytes. This unique intra- and intercellular Ag cross-linking endows the multifunctional mAb nanoarray with potent apoptosis activity. The exceptional apoptosis, complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC) that are synchronously evoked by the nano PL-RB are further synergistically promoted via enhanced permeability and retention (EPR), which resulted in high intratumor accumulation and excellent anti-lymphoma efficiency.

Novel targets for HIV therapy.

PubMed

Greene, Warner C; Debyser, Zeger; Ikeda, Yasuhiro; Freed, Eric O; Stephens, Edward; Yonemoto, Wes; Buckheit, Robert W; Esté, José A; Cihlar, Tomas

2008-12-01

There are currently 25 drugs belonging to 6 different inhibitor classes approved for the treatment of human immunodeficiency virus (HIV) infection. However, new anti-HIV agents are still needed to confront the emergence of drug resistance and various adverse effects associated with long-term use of antiretroviral therapy. The 21st International Conference on Antiviral Research, held in April 2008 in Montreal, Canada, therefore featured a special session focused on novel targets for HIV therapy. The session included presentations by world-renowned experts in HIV virology and covered a diverse array of potential targets for the development of new classes of HIV therapies. This review contains concise summaries of discussed topics that included Vif-APOBEC3G, LEDGF/p75, TRIM 5alpha, virus assembly and maturation, and Vpu. The described viral and host factors represent some of the most noted examples of recent scientific breakthroughs that are opening unexplored avenues to novel anti-HIV target discovery and validation, and should feed the antiretroviral drug development pipeline in the near future.

Statins and myositis: the role of anti-HMGCR antibodies.

PubMed

Selva-O'Callaghan, Albert; Alvarado-Cardenas, Marcelo; Marin, Ana; Pinal-Fernandez, Iago

2015-01-01

Muscle toxicity is a recognized adverse effect of statin use. Recently, a new myositis syndrome was described in association with antibodies directed against the pharmacologic target of statins, anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase (anti-HMGCR antibody). The patient's genetic background, characteristic histologic patterns (immune-mediated necrotizing myopathy), and presence of anti-HMGCR antibodies define the syndrome. In most patients, statin discontinuation is insufficient to reverse the myositis symptoms, and immunosuppressive therapy is needed. The mechanisms by which these antibodies may lead to disease are not fully elucidated. Several important questions remain unsolved and warrant further research.

Assessing the response to targeted therapies in renal cell carcinoma: technical insights and practical considerations.

PubMed

Bex, Axel; Fournier, Laure; Lassau, Nathalie; Mulders, Peter; Nathan, Paul; Oyen, Wim J G; Powles, Thomas

2014-04-01

The introduction of targeted agents for the treatment of renal cell carcinoma (RCC) has resulted in new challenges for assessing response to therapy, and conventional response criteria using computed tomography (CT) are limited. It is widely recognised that targeted therapies may lead to significant necrosis without significant reduction in tumour size. In addition, the vascular effects of antiangiogenic therapy may occur long before there is any reduction in tumour size. To perform a systematic review of conventional and novel imaging methods for the assessment of response to targeted agents in RCC and to discuss their use from a clinical perspective. Relevant databases covering the period January 2006 to April 2013 were searched for studies reporting on the use of anatomic and functional imaging techniques to predict response to targeted therapy in RCC. Inclusion criteria were randomised trials, nonrandomised controlled studies, retrospective case series, and cohort studies. Reviews, animal and preclinical studies, case reports, and commentaries were excluded. A narrative synthesis of the evidence is presented. A total of 331 abstracts and 76 full-text articles were assessed; 34 studies met the inclusion criteria. Current methods of response assessment in RCC include anatomic methods--based on various criteria including Choi, size and attenuation CT, and morphology, attenuation, size, and structure--and functional techniques including dynamic contrast-enhanced (DCE) CT, DCE-magnetic resonance imaging, DCE-ultrasonography, positron emission tomography, and approaches utilising radiolabelled monoclonal antibodies. Functional imaging techniques are promising surrogate biomarkers of response in RCC and may be more appropriate than anatomic CT-based methods. By enabling quantification of tumour vascularisation, functional techniques can directly and rapidly detect the biologic effects of antiangiogenic therapies compared with the indirect detection of belated effects

Self-assembly synthesis, tumor cell targeting, and photothermal capabilities of antibody-coated indocyanine green nanocapsules

PubMed Central

Yu, Jie; Javier, David; Yaseen, Mohammad A.; Nitin, Nitin; Richards-Kortum, Rebecca; Anvari, Bahman; Wong, Michael S.

2010-01-01

New colloidal materials that can generate heat upon irradiation are being explored for photothermal therapy as a minimally invasive approach to cancer treatment. The near-infrared dye indocyanine green (ICG) could serve as a basis for such a material, but its encapsulation and subsequent use is very difficult to carry out. We report the three-step room-temperature synthesis of ~120-nm capsules loaded with ICG within salt-crosslinked polyallylamine aggregates, and coated with anti-epidermal growth factor receptor (anti-EGFR) antibodies for tumor cell targeting capability. We studied the synthesis conditions such as temperature and water dilution to control the capsule size and characterized the size distribution via dynamic light scattering and scanning electron microscopy. We further studied the specificity of tumor cell targeting using three carcinoma cell lines with different levels of EGFR expression, and investigated the photothermal effects of ICG containing nanocapsules on EGFR-rich tumor cells. Significant thermal toxicity was observed for encapsulated ICG as compared to free ICG at 808 nm laser irradiation with radiant exposure of 6 W/cm2. These results illustrate the ability to design a colloidal material with cell targeting and heat generating capabilities using non-covalent chemistry. PMID:20092330

Targeting Transfusion-Related Acute Lung Injury: The Journey From Basic Science to Novel Therapies.

PubMed

Semple, John W; McVey, Mark J; Kim, Michael; Rebetz, Johan; Kuebler, Wolfgang M; Kapur, Rick

2018-05-01

Transfusion-related acute lung injury is characterized by the onset of respiratory distress and acute lung injury following blood transfusion, but its pathogenesis remains poorly understood. Generally, a two-hit model is presumed to underlie transfusion-related acute lung injury with the first hit being risk factors present in the transfused patient (such as inflammation), whereas the second hit is conveyed by factors in the transfused donor blood (such as antileukocyte antibodies). At least 80% of transfusion-related acute lung injury cases are related to the presence of donor antibodies such as antihuman leukocyte or antihuman neutrophil antibodies. The remaining cases may be related to nonantibody-mediated factors such as biolipids or components related to storage and ageing of the transfused blood cells. At present, transfusion-related acute lung injury is the leading cause of transfusion-related fatalities and no specific therapy is clinically available. In this article, we critically appraise and discuss recent preclinical (bench) insights related to transfusion-related acute lung injury pathogenesis and their therapeutic potential for future use at the patients' bedside in order to combat this devastating and possibly fatal complication of transfusion. We searched the PubMed database (until August 22, 2017). Using terms: "Transfusion-related acute lung injury," "TRALI," "TRALI and therapy," "TRALI pathogenesis." English-written articles focusing on transfusion-related acute lung injury pathogenesis, with potential therapeutic implications, were extracted. We have identified potential therapeutic approaches based on the literature. We propose that the most promising therapeutic strategies to explore are interleukin-10 therapy, down-modulating C-reactive protein levels, targeting reactive oxygen species, or blocking the interleukin-8 receptors; all focused on the transfused recipient. In the long-run, it may perhaps also be advantageous to explore other

Non-Covalent Assembly of Targeted Carbon Nanovectors Enables Synergistic Drug and Radiation Cancer Therapy In Vivo

PubMed Central

Sano, Daisuke; Berlin, Jacob M.; Pham, Tam T.; Marcano, Daniela C.; Valdecanas, David R.; Zhou, Ge; Milas, Luka; Myers, Jeffrey N.; Tour, James M.

2012-01-01

Current chemotherapeutics are characterized by efficient tumor cell-killing and severe side effects mostly derived from off target toxicity. Hence targeted delivery of these drugs to tumor cells is actively sought. In an in vitro system, we previously demonstrated that targeted drug delivery to cancer cells overexpressing epidermal growth factor receptor (EGFR+) can be achieved by poly(ethylene glycol)-functionalized carbon nanovectors simply mixed with a drug, paclitaxel, and an antibody that binds to the epidermal growth factor receptor, Cetuximab. This construct is unusual in that all three components are assembled through non-covalent interactions. Here we show that this same construct is effective in vivo, enhancing radiotherapy of EGFR+ tumors. This targeted nanovector system has the potential to be a new therapy for head and neck squamous cell carcinomas, deserving of further preclinical development. PMID:22316245

In Vivo Tumor Targeting and Image-Guided Drug Delivery with Antibody-Conjugated, Radiolabeled Mesoporous Silica Nanoparticles

PubMed Central

Chen, Feng; Hong, Hao; Zhang, Yin; Valdovinos, Hector F.; Shi, Sixiang; Kwon, Glen S.; Theuer, Charles P.; Barnhart, Todd E.; Cai, Weibo

2013-01-01

Since the first use of biocompatible mesoporous silica (mSiO2) nanoparticles as drug delivery vehicles, in vivo tumor targeted imaging and enhanced anti-cancer drug delivery has remained a major challenge. In this work, we describe the development of functionalized mSiO2 nanoparticles for actively targeted positron emission tomography (PET) imaging and drug delivery in 4T1 murine breast tumor-bearing mice. Our structural design involves the synthesis, surface functionalization with thiol groups, PEGylation, TRC105 antibody (specific for CD105/endoglin) conjugation, and 64Cu-labeling of uniform 80 nm sized mSiO2 nanoparticles. Systematic in vivo tumor targeting studies clearly demonstrated that 64Cu-NOTA-mSiO2-PEG-TRC105 could accumulate prominently at the 4T1 tumor site via both the enhanced permeability and retention effect and TRC105-mediated binding to tumor vasculature CD105. As a proof-of-concept, we also demonstrated successful enhanced tumor targeted delivery of doxorubicin (DOX) in 4T1 tumor-bearing mice after intravenous injection of DOX-loaded NOTA-mSiO2-PEG-TRC105, which holds great potential for future image-guided drug delivery and targeted cancer therapy. PMID:24083623

Eph receptor A10 has a potential as a target for a prostate cancer therapy

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

Nagano, Kazuya; Yamashita, Takuya; Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871

2014-07-18

Highlights: • EphA10 mRNA is overexpressed in breast, prostate and colon cancer cell lines. • EphA10 is overexpressed in clinical prostate tumors at mRNA and protein levels. • Anti-EphA10 antibodies were cytotoxic on EphA10-positive prostate cancer cells. - Abstract: We recently identified Eph receptor A10 (EphA10) as a novel breast cancer-specific protein. Moreover, we also showed that an in-house developed anti-EphA10 monoclonal antibody (mAb) significantly inhibited proliferation of breast cancer cells, suggesting EphA10 as a promising target for breast cancer therapy. However, the only other known report for EphA10 was its expression in the testis at the mRNA level. Therefore,more » the potency of EphA10 as a drug target against cancers other than the breast is not known. The expression of EphA10 in a wide variety of cancer cells was studied and the potential of EphA10 as a drug target was evaluated. Screening of EphA10 mRNA expression showed that EphA10 was overexpressed in breast cancer cell lines as well as in prostate and colon cancer cell lines. Thus, we focused on prostate cancers in which EphA10 expression was equivalent to that in breast cancers. As a result, EphA10 expression was clearly shown in clinical prostate tumor tissues as well as in cell lines at the mRNA and protein levels. In order to evaluate the potential of EphA10 as a drug target, we analyzed complement-dependent cytotoxicity effects of anti-EphA10 mAb and found that significant cytotoxicity was mediated by the expression of EphA10. Therefore, the idea was conceived that the overexpression of EphA10 in prostate cancers might have a potential as a target for prostate cancer therapy, and formed the basis for the studies reported here.« less

NCI Requests Targets for Monoclonal Antibody Production and Characterization | Office of Cancer Clinical Proteomics Research

Cancer.gov

In an effort to provide well-characterized monoclonal antibodies to the scientific community, NCI's Antibody Characterization Program requests cancer-related protein targets for affinity production and distribution. Submissions will be accepted through February 5, 2016.

NCI Requests Targets for Monoclonal Antibody Production and Characterization | Office of Cancer Clinical Proteomics Research

Cancer.gov

In an effort to provide well-characterized monoclonal antibodies to the scientific community, NCI's Antibody Characterization Program requests cancer-related protein targets for affinity production and distribution. Submissions will be accepted through July 12, 2013.

Rapid Immunochromatographic Detection of Serum Anti-α-Galactosidase A Antibodies in Fabry Patients after Enzyme Replacement Therapy

PubMed Central

Nakano, Sachie; Tsukimura, Takahiro; Togawa, Tadayasu; Ohashi, Toya; Kobayashi, Masahisa; Takayama, Katsuyoshi; Kobayashi, Yukuharu; Abiko, Hiroshi; Satou, Masatsugu; Nakahata, Tohru; Warnock, David G.; Sakuraba, Hitoshi; Shibasaki, Futoshi

2015-01-01

We developed an immunochromatography-based assay for detecting antibodies against recombinant α-galactosidase A proteins in serum. The evaluation of 29 serum samples from Fabry patients, who had received enzyme replacement therapy with agalsidase alpha and/or agalsidase beta, was performed by means of this assay method, and the results clearly revealed that the patients exhibited the same level of antibodies against both agalsidase alpha and agalsidase beta, regardless of the species of recombinant α-galactosidase A used for enzyme replacement therapy. A conventional enzyme-linked immunosorbent assay supported the results. Considering these, enzyme replacement therapy with agalsidase alpha or agalsidase beta would generate antibodies against the common epitopes in both agalsidase alpha and agalsidase beta. Most of the patients who showed immunopositive reaction exhibited classic Fabry phenotype and harbored gene mutations affecting biosynthesis of α-galactosidase A. As immunochromatography is a handy and simple assay system which can be available at bedside, this assay method would be extremely useful for quick evaluation or first screening of serum antibodies against agalsidase alpha or agalsidase beta in Fabry disease with enzyme replacement therapy. PMID:26083343

Tumor-targeted IL-2 amplifies T cell-mediated immune response induced by gene therapy with single-chain IL-12

PubMed Central

Lode, Holger N.; Xiang, Rong; Duncan, Steven R.; Theofilopoulos, Argyrios N.; Gillies, Stephen D.; Reisfeld, Ralph A.

1999-01-01

Induction, maintenance, and amplification of tumor-protective immunity after cytokine gene therapy is essential for the clinical success of immunotherapeutic approaches. We investigated whether this could be achieved by single-chain IL-12 (scIL-12) gene therapy followed by tumor-targeted IL-2 using a fusion protein containing a tumor-specific recombinant anti-ganglioside GD2 antibody and IL-2 (ch14.18-IL-2) in a poorly immunogenic murine neuroblastoma model. Herein, we demonstrate the absence of liver and bone marrow metastases after a lethal challenge with NXS2 wild-type cells only in mice (five of six animals) vaccinated with scIL-12-producing NXS2 cells and given a booster injection of low-dose ch14.18-IL-2 fusion protein. This tumor-protective immunity was effective 3 months after initial vaccination, in contrast to control animals treated with a nonspecific fusion protein or an equivalent mixture of antibody and IL-2. Only vaccinated mice receiving the tumor-specific ch14.18-IL-2 fusion protein revealed a reactivation of CD8+ T cells and subsequent MHC class I-restricted tumor target cell lysis in vitro. The sequential increase in the usage of TCR chains Vβ11 and -13 in mouse CD8+ T cells after vaccination and amplification with ch14.18-IL-2 suggests that the initial polyclonal CD8+ T cell response is effectively boosted by targeted IL-2. In conclusion, we demonstrate that a successful boost of a partially protective memory T cell immune response that is induced by scIL-12 gene therapy could be generated by tumor-specific targeting of IL-2 with a ch14.18-IL-2 fusion protein. This approach could increase success rates of clinical cancer vaccine trials. PMID:10411920

EMMPRIN as a novel target for pancreatic cancer therapy

PubMed Central

Kim, Hyunki; Zhai, Guihua; Liu, Zhiyong; Samuel, Sharon; Shah, Nemil; Helman, Emily E.; Knowles, Joseph A.; Stockard, Cecil R.; Fineberg, Naomi S.; Grizzle, William E.; Zhou, Tong; Zinn, Kurt R.; Rosenthal, Eben L.

2013-01-01

The objective of this study was to evaluate extracelluar matrix metalloproteinase (EMMPRIN) as a novel target in orthotopic pancreatic-cancer murine models. MIA PaCa-2 human pancreatic tumor cells were implanted in groups 1 and 3-7, while MIA PaCa-2 EMMPRIN knockdown cells were implanted in group 2. Dosing with anti-EMMPRIN antibody started immediately after implantation for groups 1-3 (residual tumor model) and at 21 days after cell implantation for groups 4-7 (established tumor model). Groups 3, 5, and 7 were treated with anti-EMMRPIN antibody (0.2-1.0 mg) twice weekly for 2-3 weeks, while the other groups served as the control. In residual tumor model, tumor growth of anti-EMMPRIN treated group was successfully arrested for 21 days (15±4 mm3), significantly lower than that of EMMPRIN knockdown group (80±15 mm3; p=0.001) or control group (240±41 mm3; p<0.001). In established tumor model, anti-EMMPRIN therapy lowered tumor-volume increase about 40% compared with control regardless of dose amount. Ki67-expressed cell densities of group 5 was 939±150 mm−2, significantly lower than that of group 4 (1709±145 mm−2; p=0.006). Microvessel density of group 5 (30±6 mm−2) was also significantly lower than that of group 4 (53±5 mm−2; p=0.014), while the microvessel size of group 5 (191±22 μm2) was significantly larger than that of group 4 (113±26 μm2; p=0.049). These data show the high potential of anti-EMMPRIN therapy for pancreatic cancer, and support its clinical translation. PMID:21730821

Gene Therapy and Targeted Toxins for Glioma

PubMed Central

Castro, Maria G.; Candolfi, Marianela; Kroeger, Kurt; King, Gwendalyn D.; Curtin, James F.; Yagiz, Kader; Mineharu, Yohei; Assi, Hikmat; Wibowo, Mia; Muhammad, AKM Ghulam; Foulad, David; Puntel, Mariana; Lowenstein, Pedro R.

2011-01-01

The most common primary brain tumor in adults is glioblastoma. These tumors are highly invasive and aggressive with a mean survival time of nine to twelve months from diagnosis to death. Current treatment modalities are unable to significantly prolong survival in patients diagnosed with glioblastoma. As such, glioma is an attractive target for developing novel therapeutic approaches utilizing gene therapy. This review will examine the available preclinical models for glioma including xenographs, syngeneic and genetic models. Several promising therapeutic targets are currently being pursued in pre-clinical investigations. These targets will be reviewed by mechanism of action, i.e., conditional cytotoxic, targeted toxins, oncolytic viruses, tumor suppressors/oncogenes, and immune stimulatory approaches. Preclinical gene therapy paradigms aim to determine which strategies will provide rapid tumor regression and long-term protection from recurrence. While a wide range of potential targets are being investigated preclinically, only the most efficacious are further transitioned into clinical trial paradigms. Clinical trials reported to date are summarized including results from conditionally cytotoxic, targeted toxins, oncolytic viruses and oncogene targeting approaches. Clinical trial results have not been as robust as preclinical models predicted; this could be due to the limitations of the GBM models employed. Once this is addressed, and we develop effective gene therapies in models that better replicate the clinical scenario, gene therapy will provide a powerful approach to treat and manage brain tumors. PMID:21453286

Targeted polymeric nanoparticles for cancer gene therapy

PubMed Central

Kim, Jayoung; Wilson, David R.; Zamboni, Camila G.; Green, Jordan J.

2015-01-01

In this article, advances in designing polymeric nanoparticles for targeted cancer gene therapy are reviewed. Characterization and evaluation of biomaterials, targeting ligands, and transcriptional elements are each discussed. Advances in biomaterials have driven improvements to nanoparticle stability and tissue targeting, conjugation of ligands to the surface of polymeric nanoparticles enable binding to specific cancer cells, and the design of transcriptional elements has enabled selective DNA expression specific to the cancer cells. Together, these features have improved the performance of polymeric nanoparticles as targeted non-viral gene delivery vectors to treat cancer. As polymeric nanoparticles can be designed to be biodegradable, non-toxic, and to have reduced immunogenicity and tumorigenicity compared to viral platforms, they have significant potential for clinical use. Results of polymeric gene therapy in clinical trials and future directions for the engineering of nanoparticle systems for targeted cancer gene therapy are also presented. PMID:26061296

Heart failure—potential new targets for therapy

PubMed Central

Nabeebaccus, Adam; Zheng, Sean; Shah, Ajay M.

2016-01-01

Abstract Introduction/background Heart failure is a major cause of cardiovascular morbidity and mortality. This review covers current heart failure treatment guidelines, emerging therapies that are undergoing clinical trial, and potential new therapeutic targets arising from basic science advances. Sources of data A non-systematic search of MEDLINE was carried out. International guidelines and relevant reviews were searched for additional articles. Areas of agreement Angiotensin-converting enzyme inhibitors and beta-blockers are first line treatments for chronic heart failure with reduced left ventricular function. Areas of controversy Treatment strategies to improve mortality in heart failure with preserved left ventricular function are unclear. Growing points Many novel therapies are being tested for clinical efficacy in heart failure, including those that target natriuretic peptides and myosin activators. A large number of completely novel targets are also emerging from laboratory-based research. Better understanding of pathophysiological mechanisms driving heart failure in different settings (e.g. hypertension, post-myocardial infarction, metabolic dysfunction) may allow for targeted therapies. Areas timely for developing research Therapeutic targets directed towards modifying the extracellular environment, angiogenesis, cell viability, contractile function and microRNA-based therapies. PMID:27365454

[Antibody therapy for Alzheimer's disease].

PubMed

Tabira, Takeshi; Matsumoto, Shin-Ei; Jin, Haifeng

2011-11-01

In order to avoid Abeta-induced autoimmune encephalitis, several monoclonal and polyclonal antibodies are in clinical trials. These are bapineuzumab, solanezumab, ponezumab, gantenerumab, BAN2401, gammaguard and octagam. Since each antibody has a different antigen epitope of Abeta, anti-amyloid activities are different. It is unknown which antibody is effective for Alzheimer disease, and we must wait for the result of clinical trials. Some patients who developed tissue amyloid plaque immuno-reactive (TAPIR) antibody showed slower decline after AN-1792 vaccination. We developed TAPIR-like monoclonal antibody, which was found to react with Abeta oligomers preferentially.

Upregulation of mucin glycoprotein MUC1 in the progression to esophageal adenocarcinoma and therapeutic potential with a targeted photoactive antibody-drug conjugate

PubMed Central

Haidry, Rehan J.; Oukrif, Dahmane; Khan, Saif-U-Rehman; Puccio, Ignazio; Gandy, Michael; Reinert, Halla W.; Bloom, Ellie; Rashid, Mohammed; Yahioglu, Gokhan; Deonarain, Mahendra P.; Hamoudi, Rifat; Rodriguez-Justo, Manuel; Novelli, Marco R.; Lovat, Laurence B.

2017-01-01

Background Mucin glycoprotein 1 (MUC1) is a glycosylated transmembrane protein on epithelial cells. We investigate MUC1 as a therapeutic target in Barrett’s epithelium (BE) and esophageal adenocarcinoma (EA) and provide proof of concept for a light based therapy targeting MUC1. RESULTS MUC1 was present in 21% and 30% of significantly enriched pathways comparing BE and EA to squamous epithelium respectively. MUC1 gene expression was x2.3 and x2.2 higher in BE (p=<0.001) and EA (p=0.03). MUC1 immunohistochemical expression increased during progression to EA and followed tumor invasion. HuHMFG1 based photosensitive antibody drug conjugates (ADC) showed cell internalization, MUC1 selective and light-dependent cytotoxicity (p=0.0006) and superior toxicity over photosensitizer alone (p=0.0022). Methods Gene set enrichment analysis (GSEA) evaluated pathways during BE and EA development and quantified MUC1 gene expression. Immunohistochemistry and flow cytometry evaluated the anti-MUC1 antibody HuHMFG1 in esophageal cells of varying pathological grade. Confocal microscopy examined HuHMFG1 internalization and HuHMFG1 ADCs were created to deliver a MUC1 targeted phototoxic payload. Conclusions MUC1 is a promising target in EA. Molecular and light based targeting of MUC1 with a photosensitive ADC is effective in vitro and after development may enable treatment of locoregional tumors endoscopically. PMID:28212575

NCI Requests Cancer Targets for Monoclonal Antibody Production and Characterization | Office of Cancer Clinical Proteomics Research

Cancer.gov

In an effort to provide well-characterized monoclonal antibodies to the scientific community, the National Cancer Institute (NCI) Antibody Characterization Program requests cancer-related protein targets for affinity production and distribution.

Use of thermodynamic coupling between antibody-antigen binding and phospholipid acyl chain phase transition energetics to predict immunoliposome targeting affinity.

PubMed

Klegerman, Melvin E; Zou, Yuejiao; Golunski, Eva; Peng, Tao; Huang, Shao-Ling; McPherson, David D

2014-09-01

Thermodynamic analysis of ligand-target binding has been a useful tool for dissecting the nature of the binding mechanism and, therefore, potentially can provide valuable information regarding the utility of targeted formulations. Based on a consistent coupling of antibody-antigen binding and gel-liquid crystal transition energetics observed for antibody-phosphatidylethanolamine (Ab-PE) conjugates, we hypothesized that the thermodynamic parameters and the affinity for antigen of the Ab-PE conjugates could be effectively predicted once the corresponding information for the unconjugated antibody is determined. This hypothesis has now been tested in nine different antibody-targeted echogenic liposome (ELIP) preparations, where antibody is conjugated to dipalmitoylphosphatidylethanolamine (DPPE) head groups through a thioether linkage. Predictions were satisfactory (affinity not significantly different from the population of values found) in five cases (55.6%), but the affinity of the unconjugated antibody was not significantly different from the population of values found in six cases (66.7%), indicating that the affinities of the conjugated antibody tended not to deviate appreciably from those of the free antibody. While knowledge of the affinities of free antibodies may be sufficient to judge their suitability as targeting agents, thermodynamic analysis may still provide valuable information regarding their usefulness for specific applications.

Rational Design of Iron Oxide Nanoparticles as Targeted Nanomedicines for Cancer Therapy

NASA Astrophysics Data System (ADS)

Kievit, Forrest M.

2011-07-01

Nanotechnology provides a flexible platform for the development of effective therapeutic nanomaterials that can interact specifically with a target in a biological system and provoke a desired biological response. Of the nanomaterials studied, superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as one of top candidates for cancer therapy due to their intrinsic superparamagnetism that enables non-invasive magnetic resonance imaging (MRI) and biodegradability favorable for in vivo application. This dissertation is aimed at development of SPION-based nanomedicines to overcome the current limitations in cancer therapy. These limitations include non-specificity of therapy which can harm healthy tissue, the difficulty in delivering nucleic acids for gene therapy, the formation of drug resistance, and the inability to detect and treat micrometastases. First, a SPION-based non-viral gene delivery vehicle was developed through functionalization of the SPION core with a co-polymer designed to provide stable binding of DNA and low toxicity which showed excellent gene delivery in vitro and in vivo. This SPION-based non-viral gene delivery vehicle was then activated with a targeting agent to improve gene delivery throughout a xenograft tumor of brain cancer. It was found that targeting did not promote the accumulation of SPIONs at the tumor site, but rather improved the distribution of SPIONs throughout the tumor so a higher proportion of cells received treatment. Next, the high surface area of SPIONs was utilized for loading large amounts of drug which was shown to overcome the multidrug resistance acquired by many cancer cells. Drug bound to SPIONs showed significantly higher multidrug resistant cell uptake as compared to free drug which translated into improved cell kill. Also, an antibody activated SPION was developed and was shown to be able to target micrometastases in a transgenic animal model of metastatic breast cancer. These SPION-based nanomedicines

Targeted Therapy for Melanoma

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

Quinn, Thomas; Moore, Herbert

The research project, entitled ”Targeted Therapy for Melanoma,” was focused on investigating the use of kidney protection measures to lower the non-specific kidney uptake of the radiolabeled Pb-DOTA-ReCCMSH peptide. Previous published work demonstrated that the kidney exhibited the highest non-target tissue uptake of the 212Pb/203Pb radiolabeled melanoma targeting peptide DOTA-ReCCMSH. The radiolabeled alpha-melanocyte stimulating hormone (α-MSH) peptide analog DOTA-Re(Arg 11)CCMSH, which binds the melanocortin-1 receptor over-expressed on melanoma tumor cells, has shown promise as a PRRT agent in pre-clinical studies. High tumor uptake of 212Pb labeled DOTA-Re(Arg 11)CCMSH resulted in tumor reduction or eradication in melanoma therapy studies. Of particularmore » note was the 20-50% cure rate observed when melanoma mice were treated with alpha particle emitter 212Pb. However, as with most PRRT agents, high radiation doses to the kidneys where observed. To optimize tumor treatment efficacy and reduce nephrotoxicity, the tumor to kidney uptake ratio must be improved. Strategies to reduce kidney retention of the radiolabeled peptide, while not effecting tumor uptake and retention, can be broken into several categories including modification of the targeting peptide sequence and reducing proximal tubule reabsorption.« less

Design and characteristics of cytotoxic fibroblast growth factor 1 conjugate for fibroblast growth factor receptor-targeted cancer therapy.

PubMed

Szlachcic, Anna; Zakrzewska, Malgorzata; Lobocki, Michal; Jakimowicz, Piotr; Otlewski, Jacek

2016-01-01

Fibroblast growth factor receptors (FGFRs) are attractive candidate cancer therapy targets as they are overexpressed in multiple types of tumors, such as breast, prostate, bladder, and lung cancer. In this study, a natural ligand of FGFR, an engineered variant of fibroblast growth factor 1 (FGF1V), was conjugated to a potent cytotoxic drug, monomethyl auristatin E (MMAE), and used as a targeting agent for cancer cells overexpressing FGFRs, similar to antibodies in antibody-drug conjugates. The FGF1V-valine-citrulline-MMAE conjugate showed a favorable stability profile, bound FGFRs on the cell surface specifically, and efficiently released the drug (MMAE) upon cleavage by the lysosomal protease cathepsin B. Importantly, the conjugate showed a prominent cytotoxic effect toward cell lines expressing FGFR. FGF1V-vcMMAE was highly cytotoxic at concentrations even an order of magnitude lower than those found for free MMAE. This effect was FGFR-specific as cells lacking FGFR did not show any increased mortality.

Simple and efficient generation of virus-specific T cells for adoptive therapy using anti-4-1BB antibody.

PubMed

Imahashi, Nobuhiko; Nishida, Tetsuya; Goto, Tatsunori; Terakura, Seitaro; Watanabe, Keisuke; Hanajiri, Ryo; Sakemura, Reona; Imai, Misa; Kiyoi, Hitoshi; Naoe, Tomoki; Murata, Makoto

2015-01-01

Although recent studies of virus-specific T-cell (VST) therapy for viral infections after allogeneic hematopoietic stem cell transplantation have shown promising results, simple and less time-intensive and labor-intensive methods are required to generate VSTs for the wider application of VST therapy. We investigated the efficacy of anti-CD28 and anti-4-1BB antibodies, which can provide T cells with costimulatory signals similar in strength to those of antigen-presenting cells, in generating VSTs. When peripheral blood mononuclear cells were stimulated with viral peptides together with isotype control, anti-CD28, or anti-4-1BB antibodies, anti-4-1BB antibodies yielded the highest numbers of VSTs, which were on an average 7.9 times higher than those generated with isotype control antibody. The combination of anti-CD28 and anti-4-1BB antibodies did not result in increased numbers of VSTs compared with anti-4-1BB antibody alone. Importantly, the positive effect of anti-4-1BB antibody was observed regardless of the epitopes of the VSTs. In contrast, the capacity of dendritic cells (DCs) to generate VSTs differed considerably depending on the epitopes of the VSTs. Furthermore, the numbers of VSTs generated with DCs were at most similar to those generated with the anti-4-1BB antibody. Generation of VSTs with anti-4-1BB antibody did not result in excessive differentiation or deteriorated function of the generated VSTs compared with those generated with control antibody or DCs. In conclusion, VSTs can be generated rapidly and efficiently by simply stimulating peripheral blood mononuclear cells with viral peptide and anti-4-1BB antibody without using antigen-presenting cells. We propose using anti-4-1BB antibody as a novel strategy to generate VSTs for adoptive therapy.

Crystal clear: visualizing the intervention mechanism of the PD-1/PD-L1 interaction by two cancer therapeutic monoclonal antibodies.

PubMed

Tan, Shuguang; Chen, Danqing; Liu, Kefang; He, Mengnan; Song, Hao; Shi, Yi; Liu, Jun; Zhang, Catherine W-H; Qi, Jianxun; Yan, Jinghua; Gao, Shan; Gao, George F

2016-12-01

Antibody-based PD-1/PD-L1 blockade therapies have taken center stage in immunotherapies for cancer, with multiple clinical successes. PD-1 signaling plays pivotal roles in tumor-driven T-cell dysfunction. In contrast to prior approaches to generate or boost tumor-specific T-cell responses, antibody-based PD-1/PD-L1 blockade targets tumor-induced T-cell defects and restores pre-existing T-cell function to modulate antitumor immunity. In this review, the fundamental knowledge on the expression regulations and inhibitory functions of PD-1 and the present understanding of antibody-based PD-1/PD-L1 blockade therapies are briefly summarized. We then focus on the recent breakthrough work concerning the structural basis of the PD-1/PD-Ls interaction and how therapeutic antibodies, pembrolizumab targeting PD-1 and avelumab targeting PD-L1, compete with the binding of PD-1/PD-L1 to interrupt the PD-1/PD-L1 interaction. We believe that this structural information will benefit the design and improvement of therapeutic antibodies targeting PD-1 signaling.

Intracellular trafficking of new anticancer therapeutics: antibody-drug conjugates.

PubMed

Kalim, Muhammad; Chen, Jie; Wang, Shenghao; Lin, Caiyao; Ullah, Saif; Liang, Keying; Ding, Qian; Chen, Shuqing; Zhan, Jinbiao

2017-01-01

Antibody-drug conjugate (ADC) is a milestone in targeted cancer therapy that comprises of monoclonal antibodies chemically linked to cytotoxic drugs. Internalization of ADC takes place via clathrin-mediated endocytosis, caveolae-mediated endocytosis, and pinocytosis. Conjugation strategies, endocytosis and intracellular trafficking optimization, linkers, and drugs chemistry present a great challenge for researchers to eradicate tumor cells successfully. This inventiveness of endocytosis and intracellular trafficking has given considerable momentum recently to develop specific antibodies and ADCs to treat cancer cells. It is significantly advantageous to emphasize the endocytosis and intracellular trafficking pathways efficiently and to design potent engineered conjugates and biological entities to boost efficient therapies enormously for cancer treatment. Current studies illustrate endocytosis and intracellular trafficking of ADC, protein, and linker strategies in unloading and also concisely evaluate practically applicable ADCs.

Insulin-Like Growth Factor System in Cancer: Novel Targeted Therapies

PubMed Central

Brahmkhatri, Varsha P.; Prasanna, Chinmayi; Atreya, Hanudatta S.

2015-01-01

Insulin-like growth factors (IGFs) are essential for growth and survival that suppress apoptosis and promote cell cycle progression, angiogenesis, and metastatic activities in various cancers. The IGFs actions are mediated through the IGF-1 receptor that is involved in cell transformation induced by tumour. These effects depend on the bioavailability of IGFs, which is regulated by IGF binding proteins (IGFBPs). We describe here the role of the IGF system in cancer, proposing new strategies targeting this system. We have attempted to expand the general viewpoint on IGF-1R, its inhibitors, potential limitations of IGF-1R, antibodies and tyrosine kinase inhibitors, and IGFBP actions. This review discusses the emerging view that blocking IGF via IGFBP is a better option than blocking IGF receptors. This can lead to the development of novel cancer therapies. PMID:25866791

Antibodies to watch in 2014.

PubMed

Reichert, Janice M

2014-01-01

Since 2010, mAbs has documented the biopharmaceutical industry's progress in transitioning antibody therapeutics to first Phase 3 clinical studies and regulatory review, and its success at gaining first marketing approvals for antibody-based products. This installment of the "Antibodies to watch" series outlines events anticipated to occur between December 2013 and the end of 2014, including first regulatory actions on marketing applications for vedolizumab, siltuximab, and ramucirumab, as well as the Fc fusion proteins Factor IX-Fc and Factor VIII-Fc; and the submission of first marketing applications for up to five therapeutics (secukinumab, ch14.18, onartuzumab, necitumumab, gevokizumab). Antibody therapeutics in Phase 3 studies are described, with an emphasis on those with study completion dates in 2014, including antibodies targeting interleukin-17a or the interleukin-17a receptor (secukinumab, ixekizumab, brodalumab), proprotein convertase subtilisin/kexin type 9 (alirocumab, evolocumab, bococizumab), and programmed death 1 receptor (lambrolizumab, nivolumab). Five antibodies with US Food and Drug Administration's Breakthrough Therapy designation (obinutuzumab, ofatumumab, lambrolizumab, bimagrumab, daratumumab) are also discussed.

Antibodies to watch in 2014

PubMed Central

Reichert, Janice M

2014-01-01

Since 2010, mAbs has documented the biopharmaceutical industry’s progress in transitioning antibody therapeutics to first Phase 3 clinical studies and regulatory review, and its success at gaining first marketing approvals for antibody-based products. This installment of the “Antibodies to watch” series outlines events anticipated to occur between December 2013 and the end of 2014, including first regulatory actions on marketing applications for vedolizumab, siltuximab, and ramucirumab, as well as the Fc fusion proteins Factor IX-Fc and Factor VIII-Fc; and the submission of first marketing applications for up to five therapeutics (secukinumab, ch14.18, onartuzumab, necitumumab, gevokizumab). Antibody therapeutics in Phase 3 studies are described, with an emphasis on those with study completion dates in 2014, including antibodies targeting interleukin-17a or the interleukin-17a receptor (secukinumab, ixekizumab, brodalumab), proprotein convertase subtilisin/kexin type 9 (alirocumab, evolocumab, bococizumab), and programmed death 1 receptor (lambrolizumab, nivolumab). Five antibodies with US Food and Drug Administration’s Breakthrough Therapy designation (obinutuzumab, ofatumumab, lambrolizumab, bimagrumab, daratumumab) are also discussed. PMID:24284914

Computational Prediction of Neutralization Epitopes Targeted by Human Anti-V3 HIV Monoclonal Antibodies

PubMed Central

Shmelkov, Evgeny; Krachmarov, Chavdar; Grigoryan, Arsen V.; Pinter, Abraham; Statnikov, Alexander; Cardozo, Timothy

2014-01-01

The extreme diversity of HIV-1 strains presents a formidable challenge for HIV-1 vaccine design. Although antibodies (Abs) can neutralize HIV-1 and potentially protect against infection, antibodies that target the immunogenic viral surface protein gp120 have widely variable and poorly predictable cross-strain reactivity. Here, we developed a novel computational approach, the Method of Dynamic Epitopes, for identification of neutralization epitopes targeted by anti-HIV-1 monoclonal antibodies (mAbs). Our data demonstrate that this approach, based purely on calculated energetics and 3D structural information, accurately predicts the presence of neutralization epitopes targeted by V3-specific mAbs 2219 and 447-52D in any HIV-1 strain. The method was used to calculate the range of conservation of these specific epitopes across all circulating HIV-1 viruses. Accurately identifying an Ab-targeted neutralization epitope in a virus by computational means enables easy prediction of the breadth of reactivity of specific mAbs across the diversity of thousands of different circulating HIV-1 variants and facilitates rational design and selection of immunogens mimicking specific mAb-targeted epitopes in a multivalent HIV-1 vaccine. The defined epitopes can also be used for the purpose of epitope-specific analyses of breakthrough sequences recorded in vaccine clinical trials. Thus, our study is a prototype for a valuable tool for rational HIV-1 vaccine design. PMID:24587168

Targeted therapies in gastric cancer and future perspectives.

PubMed

Yazici, Ozan; Sendur, M Ali Nahit; Ozdemir, Nuriye; Aksoy, Sercan

2016-01-14

Advanced gastric cancer (AGC) is associated with a high mortality rate and, despite multiple new chemotherapy options, the survival rates of patients with AGC remains poor. After the discovery of targeted therapies, research has focused on the new treatment options for AGC. In the last two decades, many targeted molecules were developed against AGC. Currently, two targeted therapy molecules have been approved for patients with AGC. In 2010, trastuzumab was the first molecule shown to improve survival in patients with HER2-positive AGC as part of a first-line combination regimen. In 2014, ramucirumab was the second targeted molecule to improve survival rates and was suggested as treatment for patients with AGC who had progressed after first-line platinum plus fluoropyrimidine with or without anthracycline chemotherapy. Ramucirumab was the first targeted therapy acting as a single agent in patients with advanced gastroesophageal cancers. Although these two molecules were introduced into clinical use, many other promising molecules have been tested in phase I-II trials. It is obvious that in the near future many different targeted therapies will be in use for treatment of AGC. In this review, the current status of targeted therapies in the treatment of AGC and gastroesophageal junction tumors, including HER (2-3) inhibitors, epidermal growth factor receptor inhibitors, tyrosine kinase inhibitors, antiangiogenic agents, c-MET inhibitors, mammalian target of rapamycin inhibitors, agents against other molecular pathways fibroblast growth factor, Claudins, insulin-like growth factor, heat shock proteins, and immunotherapy, will be discussed.

Targeted delivery of antibody-based therapeutic and imaging agents to CNS tumors: Crossing the blood-brain-barrier divide

PubMed Central

Chacko, Ann-Marie; Li, Chunsheng; Pryma, Daniel A.; Brem, Steven; Coukos, George; Muzykantov, Vladimir R.

2014-01-01

Introduction Brain tumors are inherently difficult to treat in large part due to the cellular blood-brain barriers (BBB) that limit the delivery of therapeutics to the tumor tissue from the systemic circulation. Virtually no large-molecules, including antibody-based proteins, can penetrate the BBB. With antibodies fast becoming attractive ligands for highly specific molecular targeting to tumor antigens, a variety of methods are being investigated to enhance the access of these agents to intracranial tumors for imaging or therapeutic applications. Areas covered This review describes the characteristics of the BBB and the vasculature in brain tumors, described as the blood-brain tumor barrier (BBTB). Antibodies targeted to molecular markers of CNS tumors will be highlighted, and current strategies for enhancing the delivery of antibodies across these cellular barriers into the brain parenchyma to the tumor will be discussed. Non-invasive imaging approaches to assess BBB/BBTB permeability and/or antibody targeting will be presented as a means of guiding the optimal delivery of targeted agents to brain tumors. Expert Opinion Pre-clinical and clinical studies highlight the potential of several approaches in increasing brain tumor delivery across the blood-brain barrier divide. However, each carries its own risks and challenges. There is tremendous potential in using neuroimaging strategies to assist in understanding and defining the challenges to translating and optimizing molecularly-targeted antibody delivery to CNS tumors to improve clinical outcomes. PMID:23751126

Antibodies Targeting Closely Adjacent or Minimally Overlapping Epitopes Can Displace One Another

PubMed Central

Abdiche, Yasmina Noubia; Yeung, Andy Yik; Ni, Irene; Stone, Donna; Miles, Adam; Morishige, Winse; Rossi, Andrea; Strop, Pavel

2017-01-01

Here we describe how real-time label-free biosensors can be used to identify antibodies that compete for closely adjacent or minimally overlapping epitopes on their specific antigen via a mechanism of antibody displacement. By kinetically perturbing one another’s binding towards their antigen via the formation of a transient trimolecular complex, antibodies can displace one another in a fully reversible and dose-dependent manner. Displacements can be readily identified when epitope binning assays are performed in a classical sandwich assay format whereby a solution antibody (analyte) is tested for binding to its antigen that is first captured via an immobilized antibody (ligand) because an inverted sandwiching response is observed when an analyte displaces a ligand, signifying the antigen’s unusually rapid dissociation from its ligand. In addition to classifying antibodies within a panel in terms of their ability to block or sandwich pair with one another, displacement provides a hybrid mechanism of competition. Using high-throughput epitope binning studies we demonstrate that displacements can be observed on any target, if the antibody panel contains appropriate epitope diversity. Unidirectional displacements occurring between disparate-affinity antibodies can generate apparent asymmetries in a cross-blocking experiment, confounding their interpretation. However, examining competition across a wide enough concentration range will often reveal that these displacements are reversible. Displacement provides a gentle and efficient way of eluting antigen from an otherwise high affinity binding partner which can be leveraged in designing reagents or therapeutic antibodies with unique properties. PMID:28060885

Antibodies Targeting Closely Adjacent or Minimally Overlapping Epitopes Can Displace One Another.

PubMed

Abdiche, Yasmina Noubia; Yeung, Andy Yik; Ni, Irene; Stone, Donna; Miles, Adam; Morishige, Winse; Rossi, Andrea; Strop, Pavel

2017-01-01

Here we describe how real-time label-free biosensors can be used to identify antibodies that compete for closely adjacent or minimally overlapping epitopes on their specific antigen via a mechanism of antibody displacement. By kinetically perturbing one another's binding towards their antigen via the formation of a transient trimolecular complex, antibodies can displace one another in a fully reversible and dose-dependent manner. Displacements can be readily identified when epitope binning assays are performed in a classical sandwich assay format whereby a solution antibody (analyte) is tested for binding to its antigen that is first captured via an immobilized antibody (ligand) because an inverted sandwiching response is observed when an analyte displaces a ligand, signifying the antigen's unusually rapid dissociation from its ligand. In addition to classifying antibodies within a panel in terms of their ability to block or sandwich pair with one another, displacement provides a hybrid mechanism of competition. Using high-throughput epitope binning studies we demonstrate that displacements can be observed on any target, if the antibody panel contains appropriate epitope diversity. Unidirectional displacements occurring between disparate-affinity antibodies can generate apparent asymmetries in a cross-blocking experiment, confounding their interpretation. However, examining competition across a wide enough concentration range will often reveal that these displacements are reversible. Displacement provides a gentle and efficient way of eluting antigen from an otherwise high affinity binding partner which can be leveraged in designing reagents or therapeutic antibodies with unique properties.

Survival and clinical outcomes of patients with melanoma brain metastasis in the era of checkpoint inhibitors and targeted therapies.

PubMed

Vosoughi, Elham; Lee, Jee Min; Miller, James R; Nosrati, Mehdi; Minor, David R; Abendroth, Roy; Lee, John W; Andrews, Brian T; Leng, Lewis Z; Wu, Max; Leong, Stanley P; Kashani-Sabet, Mohammed; Kim, Kevin B

2018-04-27

Melanoma brain metastasis is associated with an extremely poor prognosis, with a median overall survival of 4-5 months. Since 2011, the overall survival of patients with stage IV melanoma has been significantly improved with the advent of new targeted therapies and checkpoint inhibitors. We analyze the survival outcomes of patients diagnosed with brain metastasis after the introduction of these novel drugs. We performed a retrospective analysis of our melanoma center database and identified 79 patients with brain metastasis between 2011 and 2015. The median time from primary melanoma diagnosis to brain metastasis was 3.2 years. The median overall survival duration from the time of initial brain metastasis was 12.8 months. Following a diagnosis of brain metastasis, 39 (49.4%), 28 (35.4%), and 24 (30.4%) patients were treated with anti-CTLA-4 antibody, anti-PD-1 antibody, or BRAF inhibitors (with or without a MEK inhibitor), with a median overall survival of 19.2 months, 37.9 months and 12.7 months, respectively. Factors associated with significantly reduced overall survival included male sex, cerebellar metastasis, higher number of brain lesions, and treatment with whole-brain radiation therapy. Factors associated with significantly longer overall survival included treatment with craniotomy, stereotactic radiosurgery, or with anti-PD-1 antibody after initial diagnosis of brain metastasis. These results show a significant improvement in the overall survival of patients with melanoma brain metastasis in the era of novel therapies. In addition, they suggest the activity of anti-PD-1 therapy specifically in the setting of brain metastasis.

Prostate Cancer Clinical Consortium Clinical Research Site:Targeted Therapies

DTIC Science & Technology

2015-10-01

AWARD NUMBER: W81XWH-14-2-0159 TITLE: Prostate Cancer Clinical Consortium Clinical Research Site: Targeted Therapies PRINCIPAL INVESTIGATOR...Sep 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Prostate Cancer Clinical Consortium Clinical Research Site: Targeted Therapies 5b. GRANT NUMBER... therapy resistance/sensitivity, identification of new therapeutic targets through high quality genomic analyses, providing access to the highest quality

Making cell-permeable antibodies (Transbody) through fusion of protein transduction domains (PTD) with single chain variable fragment (scFv) antibodies: potential advantages over antibodies expressed within the intracellular environment (Intrabody).

PubMed

Heng, Boon Chin; Cao, Tong

2005-01-01

Over the past decade, there has been growing interest in the use of antibodies against intracellular targets. This is currently achieved through recombinant expression of the single chain variable fragment (scFv) antibody format within the cell, which is commonly referred to as an intrabody. This possesses a number of inherent advantages over RNA interference (iRNA). Firstly, the high specificity and affinity of intrabodies to target antigens is well-established, whereas iRNA has been frequently shown to exert multiple non-specific effects. Secondly, intrabodies being proteins possess a much longer active half-life compared to iRNA. Thirdly, when the active half-life of the intracellular target molecule is long, gene silencing through iRNA would be slow to yield any effect, whereas the effects of intrabody expression would be almost instantaneous. Lastly, it is possible to design intrabodies to block certain binding interactions of a particular target molecule, while sparing others. There is, however, various technical challenges faced with intrabody expression through the application of recombinant DNA technology. In particular, protein conformational folding and structural stability of the newly-synthesized intrabody within the cell is affected by reducing conditions of the intracellular environment. Also, there are overwhelming safety concerns surrounding the application of transfected recombinant DNA in human clinical therapy, which is required to achieve intrabody expression within the cell. Of particular concern are the various viral-based vectors that are commonly-used in genetic manipulation. A novel approach around these problems would be to look at the possibility of fusing protein transduction domains (PTD) to scFv antibodies, to create a 'cell-permeable' antibody or 'Transbody'. PTD are short peptide sequences that enable proteins to translocate across the cell membrane and be internalized within the cytosol, through atypical secretory and

VEGFR2-targeted fusion antibody improved NK cell-mediated immunosurveillance against K562 cells.

PubMed

Ren, Xueyan; Xie, Wei; Wang, Youfu; Xu, Menghuai; Liu, Fang; Tang, Mingying; Li, Chenchen; Wang, Min; Zhang, Juan

2016-08-01

MHC class I polypeptide-related sequence A (MICA), which is normally expressed on cancer cells, activates NK cells via NK group 2-member D pathway. However, some cancer cells escape NK-mediated immune surveillance by shedding membrane MICA causing immune suppression. To address this issue, we designed an antibody-MICA fusion targeting tumor-specific antigen (vascular endothelial growth factor receptor 2, VEGFR2) based on our patented antibody (mAb04) against VEGFR2. In vitro results demonstrate that the fusion antibody retains both the antineoplastic and the immunomodulatory activity of mAb04. Further, we revealed that it enhanced NK-mediated immunosurveillance against K562 cells through increasing degranulation and cytokine production of NK cells. The overall data suggest our new fusion protein provides a promising approach for cancer-targeted immunotherapy and has prospects for potential application of chronic myeloid leukemia.

Oligo-branched peptides for tumor targeting: from magic bullets to magic forks.

PubMed

Falciani, Chiara; Pini, Alessandro; Bracci, Luisa

2009-02-01

Selective targeting of tumor cells is the final goal of research and drug discovery for cancer diagnosis, imaging and therapy. After the invention of hybridoma technology, the concept of magic bullet was introduced into the field of oncology, referring to selective killing of tumor cells, by specific antibodies. More recently, small molecules and peptides have also been proposed as selective targeting agents. We analyze the state of the art of tumor-selective agents that are presently available and tested in clinical settings. A novel approach based on 'armed' oligo-branched peptides as tumor targeting agents, is discussed and compared with existing tumor-selective therapies mediated by antibodies, small molecules or monomeric peptides. Oligo-branched peptides could be novel drugs that combine the advantages of antibodies and small molecules.

[Effective combination therapy of plasma exchange and subsequent cyclophosphamide pulses for catastrophic antiphospholipid antibody syndrome: a case report].

PubMed

Miyamae, T; Imagawa, T; Ito, S; Katakura, S; Mori, M; Ibe, M; Mitsuda, T; Aihara, Y; Nakanishi, S; Kohri, T; Yokota, S

1999-06-01

A 7-year-old girl with catastrophic antiphospholipid antibody syndrome was described. She firstly admitted to the local hospital with the complaints of persistent fever and abdominal pain, and was diagnosed as systemic lupus erythematosus with the laboratory findings as follows; positive for antinuclear antibody, anti-DNA antibody, and platelet-associated IgG, thrombocytopenia, and hypocomplementemia. 10 days after the initiation of oral prednisolone, she suddenly manifested tonic convulsion and unconsciousness accompanied by high fever. Because of the unresponsiveness to the methylprednisolone pulse therapy for supposed CNS lupus, she was transferred to our hospital. Her unconsciousness persisted, and pulsation on dorsalis pedis was not palpable on admission. Laboratory investigation revealed the falsely positive VDRL, a prolonged aPTT, positive for lupus-anticoagulant and antiphospholipid antibody. The magnetic resonance image demonstrated multiple spotty hyperintensity (T2) in the brain consistent with multiple hemorrhagic infarcts. Arteriogram demonstrated the infarct of dorsalis pedis, and coronary aneurysms. These findings were compatible with the criteria of catastrophic antiphospholipid antibody syndrome, she was diagnosed as catastrophic antiphospholipid antibody syndrome. The plasma exchange and subsequent cyclophosphamide-pulse therapy, which was given once a month for first 6 months, and later, at 3 months intervals, was effectively administered. This combination and oral anti-thrombotic therapy revealed effective for this kind of fatal disorder.

NCI Requests Cancer Targets for Monoclonal Antibody Production and Characterization | Office of Cancer Clinical Proteomics Research

Cancer.gov

In an effort to provide well-characterized monoclonal antibodies to the scientific community, NCI's Antibody Characterization Program requests cancer-related protein targets for affinity production and distribution. Submissions will be accepted through July 11, 2014.

scFv-based “grababody” as a general strategy to improve recruitment of immune effector cells to antibody-targeted tumors

PubMed Central

Cai, Zheng; Fu, Ting; Nagai, Yasuhiro; Lam, Lian; Yee, Marla; Zhu, Zhiqiang; Zhang, Hongtao

2013-01-01

Recruitment of immune cells to tumor cells targeted by a therapeutic antibody can heighten the antitumor efficacy of the antibody. For example, p185her2/neu-targeting antibodies not only downregulate the p185her2/neu kinase (ERBB2) but also trigger complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) through the antibody Fc region. Here we describe a generalized strategy to improve immune cell recruitment to targeted cancer cells, using a modified scFv antibody we call a “grababody” that binds the target protein and endogenous immunoglobulins. The model system we used to illustrate the utility of this platform recognizes p185her2/neu and includes an IgG binding domain. The recombinant scFv grababody that was created recruited circulating human IgGs and attracted immune cells carrying Fc receptors to tumor cells that expressed p185her2/neu. The presence of the IgG binding domain significantly enhanced CDC and ADCC activity and improved anti-tumor activity in vivo. Our results illustrate a novel general approach to improve antibody-like proteins for therapeutic applications. PMID:23396586

Will nanotechnology influence targeted cancer therapy?

PubMed Central

Grimm, Jan; Scheinberg, David A.

2011-01-01

The rapid development of techniques that enable synthesis (and manipulation) of matter on the nanometer scale, as well as the development of new nano-materials, will play a large role in disease diagnosis and treatment, specifically in targeted cancer therapy. Targeted nanocarriers are an intriguing means to selectively deliver high concentrations of cytotoxic agents or imaging labels directly to the cancer site. Often solubility issues and an unfavorable biodistribution can result in a suboptimal response of novel agents even though they are very potent. New nanoparticulate formulations allow simultaneous imaging and therapy (“theranostics”), which can provide a realistic means for the clinical implementation of such otherwise suboptimal formulations. In this review we will not attempt to provide a complete overview of the rapidly enlarging field of nanotechnology in cancer; rather, we will present properties specific to nanoparticles, and examples of their uses, which demonstrate their importance for targeted cancer therapy. PMID:21356476

Optimization of Antibody-Conjugated Magnetic Nanoparticles for Target Preconcentration and Immunoassays

DTIC Science & Technology

2010-01-01

protein, AlexaFluor647– chicken IgG (Alexa647–chick IgG). Antibody-labeled MNPs (Alexa647– chick–MNPs) were used to preconcentrate the target via magnetic...separation and as the tracer to dem- onstrate binding to slides modified with anti- chicken IgG as a capture agent. A full optimization study of the...magnetically assisted transport evanescent field fluoroimmunoassay; Alexa647–chick–MNPs, MNPs functionalized with fluorescently labeled target chicken IgG

Preclinical Evaluation of Sequential Combination of Oncolytic Adenovirus Delta-24-RGD and Phosphatidylserine-Targeting Antibody in Pancreatic Ductal Adenocarcinoma.

PubMed

Dai, Bingbing; Roife, David; Kang, Ya'an; Gumin, Joy; Rios Perez, Mayrim V; Li, Xinqun; Pratt, Michael; Brekken, Rolf A; Fueyo-Margareto, Juan; Lang, Frederick F; Fleming, Jason B

2017-04-01

Delta-24-RGD (DNX-2401) is a conditional replication-competent oncolytic virus engineered to preferentially replicate in and lyse tumor cells with abnormality of p16/RB/E2F pathway. In a phase I clinical trial, Delta-24-RGD has shown favorable safety profile and promising clinical efficacy in brain tumor, which prompted us to evaluate its anticancer activity in pancreatic ductal adenocarcinoma (PDAC), which also has high frequency of homozygous deletion and promoter methylation of CDKN2A encoding the p16 protein. Our results demonstrate that Delta-24-RGD can induce dramatic cytotoxicity in a subset of PDAC cell lines with high cyclin D1 expression. Induction of autophagy and apoptosis by Delta-24-RGD in sensitive PDAC cells was confirmed with LC3B-GFP autophagy reporter and acridine orange staining as well as Western blotting analysis of LC3B-II expression. Notably, we found that Delta-24-RGD induced phosphatidylserine exposure in infected cells independent of cells' sensitivity to Delta-24-RGD, which renders a rationale for combination of Delta-24-RGD viral therapy and phosphatidylserine targeting antibody for PDAC. In a mouse PDAC model derived from a liver metastatic pancreatic cancer cell line, Delta-24-RGD significantly inhibited tumor growth compared with control ( P < 0.001), and combination of phosphatidylserine targeting antibody 1N11 further enhanced its anticancer activity ( P < 0.01) possibly through inducing synergistic anticancer immune responses. Given that these 2 agents are currently in clinical evaluation, our study warrants further clinical evaluation of this novel combination strategy in pancreatic cancer therapy. Mol Cancer Ther; 16(4); 662-70. ©2016 AACR . ©2017 American Association for Cancer Research.

HER2-Targeted Polyinosine/Polycytosine Therapy Inhibits Tumor Growth and Modulates the Tumor Immune Microenvironment.

PubMed

Zigler, Maya; Shir, Alexei; Joubran, Salim; Sagalov, Anna; Klein, Shoshana; Edinger, Nufar; Lau, Jeffrey; Yu, Shang-Fan; Mizraji, Gabriel; Globerson Levin, Anat; Sliwkowski, Mark X; Levitzki, Alexander

2016-08-01

The development of targeted therapies that affect multiple signaling pathways and stimulate antitumor immunity is greatly needed. About 20% of patients with breast cancer overexpress HER2. Small molecules and antibodies targeting HER2 convey some survival benefits; however, patients with advanced disease succumb to the disease under these treatment regimens, possibly because HER2 is not completely necessary for the survival of the targeted cancer cells. In the present study, we show that a polyinosine/polycytosine (pIC) HER2-homing chemical vector induced the demise of HER2-overexpressing breast cancer cells, including trastuzumab-resistant cells. Targeting pIC to the tumor evoked a number of cell-killing mechanisms, as well as strong bystander effects. These bystander mechanisms included type I IFN induction, immune cell recruitment, and activation. The HER2-targeted pIC strongly inhibited the growth of HER2-overexpressing tumors in immunocompetent mice. The data presented here could open additional avenues in the treatment of HER2-positive breast cancer. Cancer Immunol Res; 4(8); 688-97. ©2016 AACR. ©2016 American Association for Cancer Research.

Entering the Era of Targeted Therapy for Chronic Lymphocytic Leukemia: Impact on the Practicing Clinician

PubMed Central

Byrd, John C.; Jones, Jeffrey J.; Woyach, Jennifer A.; Johnson, Amy J.; Flynn, Joseph M.

2014-01-01

Purpose Chemoimmunotherapy has been the standard of care for chronic lymphocytic leukemia (CLL). However, the introduction of B-cell receptor (BCR) kinase inhibitors such as ibrutinib has the potential to eliminate the role of chemotherapy in the treatment of CLL. How to best incorporate old and new therapies for CLL in this landscape is increasingly complex. Methods This article reviews current data available to clinicians and integrates these data to provide a strategy that can be used to approach the treatment of CLL in the era of BCR signaling inhibitors. Results Current strategies separate patients based on age or functional status as well as genetics [presence or absence of del(17)(p13.1)]. In the era of targeted therapy, this will likely continue based on current available data. Phase III studies support chemoimmunotherapy as the initial standard therapy for patients without del(17)(p13.1). Choice of chemotherapy (fludarabine plus cyclophosphamide, bendamustine, or chlorambucil) and anti-CD20 antibody (rituximab, ofatumumab, or obinutuzumab) varies based on regimen and patient status. For patients with del(17)(p13.1), no standard initial therapy exists, although several options supported by phase II clinical trials (methylprednisolone plus alemtuzumab or ibrutinib) seem better than chemoimmunotherapy. Treatment of relapsed CLL seems to be best supported by ibrutinib-based therapy. Completion of trials with ibrutinib and other new agents in the near future will offer opportunity for chemotherapy-free treatment across all groups of CLL. Conclusion Therapy for CLL has evolved significantly over the past decade with introduction of targeted therapy for CLL. This has the potential to completely transform how CLL is treated in the future. PMID:25049322

Novel biotechnology approaches in colorectal cancer diagnosis and therapy.

PubMed

Kavousipour, Soudabeh; Khademi, Fathemeh; Zamani, Mozhdeh; Vakili, Bahareh; Mokarram, Pooneh

2017-06-01

With ever-increasing molecular information about colorectal cancer (CRC), there is an expectation to detect more sensitive and specific molecular markers for new advanced diagnostic methods that can surpass the limitations of current screening tests. Moreover, enhanced molecular pathology knowledge about cancer has led to the development of targeted therapies, designed to interfere with specific aberrant biological pathways in cancer. Furthermore, biotechnology has opened a new window in CRC diagnosis and treatment by introducing different application of antibodies, antibody fragments, non-Ig scaffold proteins, and aptamers in targeted therapy and drug delivery. This review summarizes the molecular diagnostic and therapeutic approaches in CRC with a focus on genetic and epigenetic alterations, protein and metabolite markers as well as targeted therapy and drug delivery by Ig-scaffold proteins, non-Ig scaffold proteins, nanobodies, and aptamers.

Boron neutron capture therapy: Moving toward targeted cancer therapy.

PubMed

Mirzaei, Hamid Reza; Sahebkar, Amirhossein; Salehi, Rasoul; Nahand, Javid Sadri; Karimi, Ehsan; Jaafari, Mahmoud Reza; Mirzaei, Hamed

2016-01-01

Boron neutron capture therapy (BNCT) occurs when a stable isotope, boton-10, is irradiated with low-energy thermal neutrons to yield stripped down helium-4 nuclei and lithium-7 nuclei. It is a binary therapy in the treatment of cancer in which a cytotoxic event is triggered when an atom placed in a cancer cell. Here, we provide an overview on the application of BNCT in cancer therapy as well as current preclinical and clinical evidence on the efficacy of BNCT in the treatment of melanoma, brain tumors, head and neck cancer, and thyroid cancer. Several studies have shown that BNCT is effective in patients who had been treated with a full dose of conventional radiotherapy, because of its selectivity. In addition, BNCT is dependent on the normal/tumor tissue ratio of boron distribution. Increasing evidence has shown that BNCT can be combined with different drug delivery systems to enhance the delivery of boron to cancer cells. The flexibility of BNCT to be used in combination with different tumor-targeting approaches has made this strategy a promising option for cancer therapy. This review aims to provide a state-of-the-art overview of the recent advances in the use of BNCT for targeted therapy of cancer.

Targeting glioma stem cells enhances anti-tumor effect of boron neutron capture therapy

PubMed Central

Sun, Ting; Li, Yanyan; Huang, Yulun; Zhang, Zizhu; Yang, Weilian; Du, Ziwei; Zhou, Youxin

2016-01-01

The uptake of (10)boron by tumor cells plays an important role for cell damage in boron neutron capture therapy (BNCT). CD133 is frequently expressed in the membrane of glioma stem cells (GSCs), resistant to radiotherapy and chemotherapy, and represents a potential therapeutic target. To increase (10)boron uptake in GSCs, we created a polyamido amine dendrimer, conjugated CD133 monoclonal antibodies, encapsulating mercaptoundecahydrododecaborate (BSH) in void spaces, and monitored the uptake of the bioconjugate nanoparticles by GSCs in vitro and in vivo. Fluorescence microscopy showed the specific uptake of the bioconjugate nanoparticles by CD133-positive GSCs. Treatment with the biconjugate nanoparticles resulted in a significant lethal effect after neutron radiation due to efficient and CD133-independent cellular targeting and uptake in CD133-expressing GSCs. A significantly longer survival occurred in combination with the biconjugate nanoparticles and BSH compared with BSH alone in human intracranial GBM models employing CD133-positive GSCs xenografts. Our data demonstrated that this bioconjugate nanoparticle targets human CD133-positive GSCs and is a potential boron agent in BNCT. PMID:27191269

Targeting glioma stem cells enhances anti-tumor effect of boron neutron capture therapy.

PubMed

Sun, Ting; Li, Yanyan; Huang, Yulun; Zhang, Zizhu; Yang, Weilian; Du, Ziwei; Zhou, Youxin

2016-07-12

The uptake of (10)boron by tumor cells plays an important role for cell damage in boron neutron capture therapy (BNCT). CD133 is frequently expressed in the membrane of glioma stem cells (GSCs), resistant to radiotherapy and chemotherapy, and represents a potential therapeutic target. To increase (10)boron uptake in GSCs, we created a polyamido amine dendrimer, conjugated CD133 monoclonal antibodies, encapsulating mercaptoundecahydrododecaborate (BSH) in void spaces, and monitored the uptake of the bioconjugate nanoparticles by GSCs in vitro and in vivo. Fluorescence microscopy showed the specific uptake of the bioconjugate nanoparticles by CD133-positive GSCs. Treatment with the biconjugate nanoparticles resulted in a significant lethal effect after neutron radiation due to efficient and CD133-independent cellular targeting and uptake in CD133-expressing GSCs. A significantly longer survival occurred in combination with the biconjugate nanoparticles and BSH compared with BSH alone in human intracranial GBM models employing CD133-positive GSCs xenografts. Our data demonstrated that this bioconjugate nanoparticle targets human CD133-positive GSCs and is a potential boron agent in BNCT.

Minimizing antibody surface density on liposomes while sustaining cytokine-activated EC targeting.

PubMed

Almeda, Dariela; Wang, Biran; Auguste, Debra T

2015-02-01

Liposomes may be engineered to target inflamed endothelium by mimicking ligand-receptor interactions between leukocytes and cytokine-activated endothelial cells (ECs). The upregulation and assembly of vascular cell adhesion molecule-1 (VCAM1) and E-selectin on the cell membrane upon exposure to cytokines have shown potential for drug delivery vehicles to target sites of chronic endothelial inflammation, such as atherosclerosis and cancer. Herein, we characterized EC surfaces by measuring the E-selectin and VCAM1 surface densities and adhesion forces of aVCAM1 and aE-selectin to ECs. We quantified the antibody density, ratio, and diffusivity of liposomes to achieve significant binding and internalization. At 1 h, the 1:1 ratio of VCAM1:E-selectin antibodies was significantly higher than 1:0 and 0:1. Significant binding and uptake was achieved at aE-selectin densities as low as 400 molecules/μm(2). The highest levels of binding and uptake were achieved when using a 1:1 ratio of VCAM1:E-selectin antibodies at a density of 1000 molecules/μm(2); this density is 85% lower than previous reports. The binding and uptake of functionalized liposomes were reduced to levels comparable to IgG functionalized liposomes upon a 10-fold reduction in liposome membrane diffusivity. We conclude with a liposomal design that discriminates between healthy and inflamed endothelium while reducing antibody surface presentation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Tumor Specific Detection of an Optically Targeted Antibody Combined with a Quencher-conjugated Neutravidin “Quencher-Chaser”: A Dual “Quench and Chase” Strategy to Improve Target to Non-target Ratios for Molecular Imaging of Cancer

PubMed Central

Ogawa, Mikako; Kosaka, Nobuyuki; Choyke, Peter L; Kobayashi, Hisataka

2009-01-01

In vivo molecular cancer imaging with monoclonal antibodies has great potential not only for cancer detection but also for cancer characterization. However, the prolonged retention of intravenously injected antibody in the blood causes low target tumor-to-background ratio (TBR). Avidin has been used as a “chase” to clear the unbound, circulating biotinylated antibody and decrease the background signal. Here, we utilize a combined approach of a Fluorescence Resonance Energy Transfer (FRET) quenched antibody with an “avidin chase” to increase TBR. Trastuzumab, a humanized monoclonal antibody against human epidermal growth factor receptor type 2 (HER2), was biotinylated and conjugated with the near-infrared (NIR) fluorophore Alexa680 to synthesize Tra-Alexa680-biotin. Next, the FRET quencher, QSY-21, was conjugated to avidin, neutravidin (nAv) or streptavidin (sAv), thus creating Av-QSY21, nAv-QSY21 or sAv-QSY21 as “chasers”. The fluorescence was quenched in vitro by binding Tra-Alexa680-biotin to Av-QSY21, nAv-QSY21 or sAv-QSY21. To evaluate if the injection of quencher-conjugated avidin-derivatives can improve target TBR by using a dual “quench and chase” strategy, both target (3T3/HER2+) and non-target (Balb3T3/ZsGreen) tumor bearing mice were employed. The “FRET quench” effect induced by all the QSY21 avidin-based conjugates reduced but did not totally eliminate background signal from the blood pool. The addition of nAv-QSY21 administration increased target TBR mainly due to the “chase” effect where unbound conjugated antibody was preferentially cleared to the liver. The relatively slow clearance of unbound nAv-QSY21 leads to further reductions in background signal by leaking out of the vascular space and binding to unbound antibodies in the extravascular space of tumors resulting in decreased non-target tumor-to-background ratios but increased target TBR due to the “FRET quench” effect because target-bound antibodies were internalized

New Strategies Using Antibody Combinations to Increase Cancer Treatment Effectiveness

PubMed Central

Corraliza-Gorjón, Isabel; Somovilla-Crespo, Beatriz; Santamaria, Silvia; Garcia-Sanz, Jose A.; Kremer, Leonor

2017-01-01

Antibodies have proven their high value in antitumor therapy over the last two decades. They are currently being used as the first-choice to treat some of the most frequent metastatic cancers, like HER2+ breast cancers or colorectal cancers, currently treated with trastuzumab (Herceptin) and bevacizumab (Avastin), respectively. The impressive therapeutic success of antibodies inhibiting immune checkpoints has extended the use of therapeutic antibodies to previously unanticipated tumor types. These anti-immune checkpoint antibodies allowed the cure of patients devoid of other therapeutic options, through the recovery of the patient’s own immune response against the tumor. In this review, we describe how the antibody-based therapies will evolve, including the use of antibodies in combinations, their main characteristics, advantages, and how they could contribute to significantly increase the chances of success in cancer therapy. Indeed, novel combinations will consist of mixtures of antibodies against either different epitopes of the same molecule or different targets on the same tumor cell; bispecific or multispecific antibodies able of simultaneously binding tumor cells, immune cells or extracellular molecules; immunomodulatory antibodies; antibody-based molecules, including fusion proteins between a ligand or a receptor domain and the IgG Fab or Fc fragments; autologous or heterologous cells; and different formats of vaccines. Through complementary mechanisms of action, these combinations could contribute to elude the current limitations of a single antibody which recognizes only one particular epitope. These combinations may allow the simultaneous attack of the cancer cells by using the help of the own immune cells and exerting wider therapeutic effects, based on a more specific, fast, and robust response, trying to mimic the action of the immune system. PMID:29312320

Bispecific small molecule-antibody conjugate targeting prostate cancer.

PubMed

Kim, Chan Hyuk; Axup, Jun Y; Lawson, Brian R; Yun, Hwayoung; Tardif, Virginie; Choi, Sei Hyun; Zhou, Quan; Dubrovska, Anna; Biroc, Sandra L; Marsden, Robin; Pinstaff, Jason; Smider, Vaughn V; Schultz, Peter G

2013-10-29

Bispecific antibodies, which simultaneously target CD3 on T cells and tumor-associated antigens to recruit cytotoxic T cells to cancer cells, are a promising new approach to the treatment of hormone-refractory prostate cancer. Here we report a site-specific, semisynthetic method for the production of bispecific antibody-like therapeutics in which a derivative of the prostate-specific membrane antigen-binding small molecule DUPA was selectively conjugated to a mutant αCD3 Fab containing the unnatural amino acid, p-acetylphenylalanine, at a defined site. Homogeneous conjugates were generated in excellent yields and had good solubility. The efficacy of the conjugate was optimized by modifying the linker structure, relative binding orientation, and stoichiometry of the ligand. The optimized conjugate showed potent and selective in vitro activity (EC50 ~ 100 pM), good serum half-life, and potent in vivo activity in prophylactic and treatment xenograft mouse models. This semisynthetic approach is likely to be applicable to the generation of additional bispecific agents using drug-like ligands selective for other cell-surface receptors.

Bispecific small molecule–antibody conjugate targeting prostate cancer

PubMed Central

Kim, Chan Hyuk; Axup, Jun Y.; Lawson, Brian R.; Yun, Hwayoung; Tardif, Virginie; Choi, Sei Hyun; Zhou, Quan; Dubrovska, Anna; Biroc, Sandra L.; Marsden, Robin; Pinstaff, Jason; Smider, Vaughn V.; Schultz, Peter G.

2013-01-01

Bispecific antibodies, which simultaneously target CD3 on T cells and tumor-associated antigens to recruit cytotoxic T cells to cancer cells, are a promising new approach to the treatment of hormone-refractory prostate cancer. Here we report a site-specific, semisynthetic method for the production of bispecific antibody-like therapeutics in which a derivative of the prostate-specific membrane antigen-binding small molecule DUPA was selectively conjugated to a mutant αCD3 Fab containing the unnatural amino acid, p-acetylphenylalanine, at a defined site. Homogeneous conjugates were generated in excellent yields and had good solubility. The efficacy of the conjugate was optimized by modifying the linker structure, relative binding orientation, and stoichiometry of the ligand. The optimized conjugate showed potent and selective in vitro activity (EC50 ∼100 pM), good serum half-life, and potent in vivo activity in prophylactic and treatment xenograft mouse models. This semisynthetic approach is likely to be applicable to the generation of additional bispecific agents using drug-like ligands selective for other cell-surface receptors. PMID:24127589

Temozolomide combined with PD-1 Antibody therapy for mouse orthotopic glioma model.

PubMed

Dai, Bailing; Qi, Na; Li, Junchao; Zhang, Guilong

2018-07-02

Temozolomide (TMZ) is the most frequent adjuvant chemotherapy drug in gliomas. PDL1 expresses on various tumors, including gliomas, and anti-PD-1 antibodies have been approved for treating some tumors by FDA. This study was to evaluate the therapeutical potential of combined TMZ with anti-PD-1 antibody therapy for mouse orthotopic glioma model. We performed C57BL/6 mouse orthotopic glioma model by stereotactic intracranial implantation of glioma cell line GL261, mice were randomly divided into four groups: (1) control group; (2) TMZ group; (3) anti-PD-1 antibody group; (4) TMZ combined with anti-PD-1 antibody group. Then the volume or size of tumor was assessed by 7.0 T MRI and immunohistochemistry, and the number of CD4 and CD8 infiltrating cells in brain tumor and spleen was evaluated by immunohistochemistry. Western blot was used to evaluate the expression of PDL1. Furthermore, Overall survival of each group mice was also evaluated. Overall survival was significantly improved in combined group compared to other groups (χ2 = 32.043, p < 0.01). The volume or size of tumor was significantly decreased in combined group compared with other groups (F = 42.771, P < 0.01). And the number of CD4 and CD8 infiltrating cells in brain tumor was also obviously increased in combined group (CD4 F = 45.67, P < 0.01; CD8 F = 53.75, P < 0.01). Anti-PD1 antibody combined with TMZ therapy for orthotopic mouse glioma model could significantly improve the survival time of tumor-bear mice. Thus, this study provides the effective preclinical evidence for support clinical chemotherapy combined with immunotherapy for glioma patients. Copyright © 2018 Elsevier Inc. All rights reserved.

Antibody Drug Conjugates: Application of Quantitative Pharmacology in Modality Design and Target Selection.

PubMed

Sadekar, S; Figueroa, I; Tabrizi, M

2015-07-01

Antibody drug conjugates (ADCs) are a multi-component modality comprising of an antibody targeting a cell-specific antigen, a potent drug/payload, and a linker that can be processed within cellular compartments to release payload upon internalization. Numerous ADCs are being evaluated in both research and clinical settings within the academic and pharmaceutical industry due to their ability to selectively deliver potent payloads. Hence, there is a clear need to incorporate quantitative approaches during early stages of drug development for effective modality design and target selection. In this review, we describe a quantitative approach and framework for evaluation of the interplay between drug- and systems-dependent properties (i.e., target expression, density, localization, turnover, and affinity) in order to deliver a sufficient amount of a potent payload into the relevant target cells. As discussed, theoretical approaches with particular considerations given to various key properties for the target and modality suggest that delivery of the payload into particular effect cells to be more sensitive to antigen concentrations for targets with slow turnover rates as compared to those with faster internalization rates. Further assessments also suggest that increasing doses beyond the threshold of the target capacity (a function of target internalization and expression) may not impact the maximum amount of payload delivered to the intended effect cells. This article will explore the important application of quantitative sciences in selection of the target and design of ADC modalities.

Radioimmunotherapy with monoclonal antibodies. A new horizon in nuclear medicine therapy?

PubMed

Sautter-Bihl, M L; Bihl, H

1994-08-01

Radioimmunotherapy (RIT) with labeled tumor-associated monoclonal antibodies (MAbs) is a promising concept in oncology, which essentially consists of biological targeting of ionising radiation to tumors. Some encouraging clinical results have been achieved with RIT. However, there are severe problems associated with both understanding the mechanisms and predicting the effectiveness of RIT. This paper reviews the results of some major clinical trials, especially in malignant lymphomas and in some solid tumors. Furthermore, problems with RIT are described such as the significance of dose inhomogeneity and dose-rate effects, the appropriate dose calculation method, the toxicity of RIT and the development of HAMAs. It is suggested that newer technologies including chimeric antibodies, multiple-step targeting protocols, bone marrow transplantation, parallel application of external radiation, heat or bioreductive drugs will enable RIT to make an essential contribution to strategies for combating cancer.

Deep Sequencing-guided Design of a High Affinity Dual Specificity Antibody to Target Two Angiogenic Factors in Neovascular Age-related Macular Degeneration* ♦

PubMed Central

Koenig, Patrick; Lee, Chingwei V.; Sanowar, Sarah; Wu, Ping; Stinson, Jeremy; Harris, Seth F.; Fuh, Germaine

2015-01-01

The development of dual targeting antibodies promises therapies with improved efficacy over mono-specific antibodies. Here, we engineered a Two-in-One VEGF/angiopoietin 2 antibody with dual action Fab (DAF) as a potential therapeutic for neovascular age-related macular degeneration. Crystal structures of the VEGF/angiopoietin 2 DAF in complex with its two antigens showed highly overlapping binding sites. To achieve sufficient affinity of the DAF to block both angiogenic factors, we turned to deep mutational scanning in the complementarity determining regions (CDRs). By mutating all three CDRs of each antibody chain simultaneously, we were able not only to identify affinity improving single mutations but also mutation pairs from different CDRs that synergistically improve both binding functions. Furthermore, insights into the cooperativity between mutations allowed us to identify fold-stabilizing mutations in the CDRs. The data obtained from deep mutational scanning reveal that the majority of the 52 CDR residues are utilized differently for the two antigen binding function and permit, for the first time, the engineering of several DAF variants with sub-nanomolar affinity against two structurally unrelated antigens. The improved variants show similar blocking activity of receptor binding as the high affinity mono-specific antibodies against these two proteins, demonstrating the feasibility of generating a dual specificity binding surface with comparable properties to individual high affinity mono-specific antibodies. PMID:26088137

Non-Covalent Functionalization of Carbon Nanovectors with an Antibody Enables Targeted Drug Delivery

PubMed Central

Berlin, Jacob M.; Pham, Tam T.; Sano, Daisuke; Mohamedali, Khalid A.; Marcano, Daniela C.; Myers, Jeffrey N.; Tour, James M.

2011-01-01

Current chemotherapeutics are characterized by efficient tumor cell-killing and severe side effects mostly derived from off target toxicity. Hence targeted delivery of these drugs to tumor cells is actively sought. We previously demonstrated that poly(ethylene glycol)-functionalized carbon nanovectors are able to sequester paclitaxel, a widely used hydrophobic cancer drug, by simple physisorption and deliver the drug for killing of cancer cells. The cell-killing when these drug-loaded carbon nanoparticles were used was equivalent to when a commercial formulation of paclitaxel was used. Here we show that by further mixing the drug-loaded nanoparticles with Cetuximab, a monoclonal antibody that recognizes the epidermal growth factor receptor (EGFR), paclitaxel is preferentially targeted to EGFR+ tumor cells in vitro. This supports progressing to in vivo studies. Moreover, the construct is unusual in that all three components are assembled through non-covalent interactions. Such non-covalent assembly could enable high-throughput screening of drug/antibody combinations. PMID:21736358

Apatinib as targeted therapy for sarcoma

PubMed Central

Li, Feng; Liao, Zhichao; Zhang, Chao; Zhao, Jun; Xing, Ruwei; Teng, Sheng; Zhang, Jin; Yang, Yun; Yang, Jilong

2018-01-01

Sarcomas are a group of malignant tumors originating from mesenchymal tissue with a variety of cell subtypes. Despite several major treatment breakthroughs, standard treatment using surgery, radiation, and chemotherapy has failed to improve overall survival. Therefore, there is an urgent need to explore new strategies and innovative therapies to further improve the survival rates of patients with sarcomas. Pathological angiogenesis has an important role in the growth and metastasis of tumors. Vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFRs) play a central role in tumor angiogenesis and represent potential targets for anticancer therapy. As a novel targeted therapy, especially with regard to angiogenesis, apatinib is a new type of small molecule tyrosine kinase inhibitor that selectively targets VEGFR-2 and has shown encouraging anticancer activity in a wide range of malignancies, including gastric cancer, non-small cell lung cancer, breast cancer, hepatocellular carcinoma, and sarcomas. In this review, we summarize the preclinical and clinical data for apatinib, focusing primarily on its use in the treatment of sarcomas. PMID:29849960

Antibodies and antibody-drug conjugates in the treatment of Hodgkin lymphoma.

PubMed

Eichenauer, Dennis A; Engert, Andreas

2014-07-01

Hodgkin lymphoma (HL) is a B cell-derived lymphoid malignancy most often affecting young adults. More than 80% of HL patients achieve long-term remission after appropriate first-line treatment consisting of multiagent chemotherapy and/or radiotherapy (RT). In addition, approximately 50% of patients with disease recurrence remain relapse-free after salvage therapy with high-dose chemotherapy followed by autologous stem cell transplantation (ASCT). However, patients with multiple relapses are mostly in a palliative situation, and novel drugs for this patient group are needed. Furthermore, novel less toxic but equally effective first-line and second-line approaches are required as therapy-related late sequelae represent a relevant cause of morbidity and mortality in HL survivors. Several antibodies and antibody-drug conjugates (ADC) targeting CD30 and CD20 have recently been evaluated in HL. Excellent response rates in heavily pretreated patients were observed with the ADC brentuximab vedotin directed against CD30. Thus, ongoing trials investigate brentuximab vedotin in different additional indications. One example is the first-line treatment of advanced HL where the drug is currently being evaluated in combination with variants of the first-line protocols ABVD (adriamycin, bleomycin, vinblastine, dacarbazine) and escalated BEACOPP (bleomycin, etoposide, adriamycin, cyclophosphamide, vincristine, procarbazine, prednisone). Anti-CD20 antibodies given either as single agent or in combination with conventional chemotherapy have also been investigated and still undergo investigation in prospective studies including HL patients. This article reviews the available data on treatment approaches including antibodies and ADC in HL patients. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mathematical modeling of antibody drug conjugates with the target and tubulin dynamics to predict AUC.

PubMed

Byun, Jong Hyuk; Jung, Il Hyo

2018-04-14

Antibody drug conjugates (ADCs)are one of the most recently developed chemotherapeutics to treat some types of tumor cells. They consist of monoclonal antibodies (mAbs), linkers, and potent cytotoxic drugs. Unlike common chemotherapies, ADCs combine selectively with a target at the surface of the tumor cell, and a potent cytotoxic drug (payload) effectively prevents microtubule polymerization. In this work, we construct an ADC model that considers both the target of antibodies and the receptor (tubulin) of the cytotoxic payloads. The model is simulated with brentuximab vedotin, one of ADCs, and used to investigate the pharmacokinetic (PK) characteristics of ADCs in vivo. It also predicts area under the curve (AUC) of ADCs and the payloads by identifying the half-life. The results show that dynamical behaviors fairly coincide with the observed data and half-life and capture AUC. Thus, the model can be used for estimating some parameters, fitting experimental observations, predicting AUC, and exploring various dynamical behaviors of the target and the receptor. Copyright © 2018 Elsevier Ltd. All rights reserved.

Chemoresistance and targeted therapies in ovarian and endometrial cancers

PubMed Central

Brasseur, Kevin; Gévry, Nicolas; Asselin, Eric

2017-01-01

Gynecological cancers are known for being very aggressive at their advanced stages. Indeed, the survival rate of both ovarian and endometrial cancers is very low when diagnosed lately and the success rate of current chemotherapy regimens is not very efficient. One of the main reasons for this low success rate is the acquired chemoresistance of these cancers during their progression. The mechanisms responsible for this acquired chemoresistance are numerous, including efflux pumps, repair mechanisms, survival pathways (PI3K/AKT, MAPK, EGFR, mTOR, estrogen signaling) and tumor suppressors (P53 and Par-4). To overcome these resistances, a new type of therapy has emerged named targeted therapy. The principle of targeted therapy is simple, taking advantage of changes acquired in malignant cancer cells (receptors, proteins, mechanisms) by using compounds specifically targeting these, thus limiting their action on healthy cells. Targeted therapies are emerging and many clinical trials targeting these pathways, frequently involved in chemoresistance, have been tested on gynecological cancers. Despite some targets being less efficient than expected as mono-therapies, the combination of compounds seems to be the promising avenue. For instance, we demonstrate using ChIP-seq analysis that estrogen downregulate tumor suppressor Par-4 in hormone-dependent cells by directly binding to its DNA regulatory elements and inhibiting estrogen signaling could reinstate Par-4 apoptosis-inducing abilities. This review will focus on the chemoresistance mechanisms and the clinical trials of targeted therapies associated with these, specifically for endometrial and ovarian cancers. PMID:28008141

Efficacy of ETI-204 monoclonal antibody as an adjunct therapy in a New Zealand white rabbit partial survival model for inhalational anthrax.

PubMed

Biron, Bethany; Beck, Katie; Dyer, David; Mattix, Marc; Twenhafel, Nancy; Nalca, Aysegul

2015-04-01

Inhalational anthrax is characterized by extensive bacteremia and toxemia as well as nonspecific to mild flu-like symptoms, until the onset of hypotension, shock, and mortality. Without treatment, the mortality rate approaches 100%. Antibiotic treatment is not always effective, and alternative treatments are needed, such as monotherapy for antibiotic-resistant inhalational anthrax or as an adjunct therapy in combination with antibiotics. The Bacillus anthracis antitoxin monoclonal antibody (MAb) ETI-204 is a high-affinity chimeric deimmunized antibody which targets the anthrax toxin protective antigen (PA). In this study, a partial protection New Zealand White (NZW) rabbit model was used to evaluate the protective efficacy of the adjunct therapy with the MAb. Following detection of PA in the blood, NZW rabbits were administered either an antibiotic (doxycycline) alone or the antibiotic in conjunction with ETI-204. Survival was evaluated to compare the efficacy of the combination adjunct therapy with that of an antibiotic alone in treating inhalational anthrax. Overall, the results from this study indicate that a subtherapeutic regimen consisting of an antibiotic in combination with an anti-PA MAb results in increased survival compared to the antibiotic alone and would provide an effective therapeutic strategy against symptomatic anthrax in nonvaccinated individuals. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Generation and characterization of a human-mouse chimeric antibody against the extracellular domain of claudin-1 for cancer therapy using a mouse model.

PubMed

Hashimoto, Yosuke; Tada, Minoru; Iida, Manami; Nagase, Shotaro; Hata, Tomoyuki; Watari, Akihiro; Okada, Yoshiaki; Doi, Takefumi; Fukasawa, Masayoshi; Yagi, Kiyohito; Kondoh, Masuo

2016-08-12

Claudin-1 (CLDN-1), an integral transmembrane protein, is an attractive target for drug absorption, prevention of infection, and cancer therapy. Previously, we generated mouse anti-CLDN-1 monoclonal antibodies (mAbs) and found that they enhanced epidermal absorption of a drug and prevented hepatitis C virus infection in human hepatocytes. Here, we investigated anti-tumor activity of a human-mouse chimeric IgG1, xi-3A2, from one of the anti-CLDN-1 mAbs, clone 3A2. Xi-3A2 accumulated in the tumor tissues in mice bearing with human CLDN-1-expressing tumor cells. Xi-3A2 activated Fcγ receptor IIIa-expressing reporter cells in the presence of human CLDN-1-expressing cells, suggesting xi-3A2 has a potential to exhibit antibody-dependent cellular cytotoxicity against CLDN-1 expressing tumor cells. We also constructed a mutant xi-3A2 antibody with Gly, Ser, and Ile substituted with Ala, Asp, and Arg at positions 236, 239, and 332 of the Fc domain. This mutant antibody showed greater activation of Fcγ receptor IIIa and in vivo anti-tumor activity in mice bearing human CLDN-1-expressing tumors than xi-3A2 did. These findings indicate that the G236A/S239D/I332E mutant of xi-3A2 might be a promising lead for tumor therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Hacking into the granuloma: could antibody antibiotic conjugates be developed for TB?

PubMed

Ekins, Sean

2014-12-01

Alternatives to small molecule or vaccine approaches to treating tuberculosis are rarely discussed. Attacking Mycobacterium tuberculosis in the granuloma represents a challenge. It is proposed that the conjugation of small molecules onto a monoclonal antibody that recognizes macrophage or lymphocytes cell surface receptors, might be a way to target the bacteria in the granuloma. This antibody drug conjugate approach is currently being used in 2 FDA approved targeted cancer therapies. The pros and cons of this proposal for further research are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antibodies: From novel repertoires to defining and refining the structure of biologically important targets.

PubMed

Conroy, Paul J; Law, Ruby H P; Caradoc-Davies, Tom T; Whisstock, James C

2017-03-01

Antibodies represent a highly successful class of molecules that bind a wide-range of targets in therapeutic-, diagnostic- and research-based applications. The antibody repertoire is composed of the building blocks required to develop an effective adaptive immune response against foreign insults. A number of species have developed novel genetic and structural mechanisms from which they derive these antibody repertoires, however, traditionally antibodies are isolated from human, and rodent sources. Due to their high-value therapeutic, diagnostic, biotechnological and research applications, much innovation has resulted in techniques and approaches to isolate novel antibodies. These approaches are bolstered by advances in our understanding of species immune repertoires, next generation sequencing capacity, combinatorial antibody discovery and high-throughput screening. Structural determination of antibodies and antibody-antigen complexes has proven to be pivotal to our current understanding of the immune repertoire for a range of species leading to advances in man-made libraries and fine tuning approaches to develop antibodies from immune-repertoires. Furthermore, the isolation of antibodies directed against antigens of importance in health, disease and developmental processes, has yielded a plethora of structural and functional insights. This review highlights the significant contribution of antibody-based crystallography to our understanding of adaptive immunity and its application to providing critical information on a range of human-health related indications. Copyright © 2017 Elsevier Inc. All rights reserved.

Novel BAFF-Receptor Antibody to Natively Folded Recombinant Protein Eliminates Drug-Resistant Human B-cell Malignancies In Vivo.

PubMed

Qin, Hong; Wei, Guowei; Sakamaki, Ippei; Dong, Zhenyuan; Cheng, Wesley A; Smith, D Lynne; Wen, Feng; Sun, Han; Kim, Kunhwa; Cha, Soungchul; Bover, Laura; Neelapu, Sattva S; Kwak, Larry W

2018-03-01

Purpose: mAbs such as anti-CD20 rituximab are proven therapies in B-cell malignancies, yet many patients develop resistance. Novel therapies against alternative targets are needed to circumvent resistance mechanisms. We sought to generate mAbs against human B-cell-activating factor receptor (BAFF-R/TNFRSF13C), which has not yet been targeted successfully for cancer therapy. Experimental Design: Novel mAbs were generated against BAFF-R, expressed as a natively folded cell surface immunogen on mouse fibroblast cells. Chimeric BAFF-R mAbs were developed and assessed for in vitro and in vivo monotherapy cytotoxicity. The chimeric mAbs were tested against human B-cell tumor lines, primary patient samples, and drug-resistant tumors. Results: Chimeric antibodies bound with high affinity to multiple human malignant B-cell lines and induced potent antibody-dependent cellular cytotoxicity (ADCC) against multiple subtypes of human lymphoma and leukemia, including primary tumors from patients who had relapsed after anti-CD20 therapy. Chimeric antibodies also induced ADCC against ibrutinib-resistant and rituximab-insensitive CD20-deficient variant lymphomas, respectively. Importantly, they demonstrated remarkable in vivo growth inhibition of drug-resistant tumor models in immunodeficient mice. Conclusions: Our method generated novel anti-BAFF-R antibody therapeutics with remarkable single-agent antitumor effects. We propose that these antibodies represent an effective new strategy for targeting and treating drug-resistant B-cell malignancies and warrant further development. Clin Cancer Res; 24(5); 1114-23. ©2017 AACR . ©2017 American Association for Cancer Research.

Deep Sequencing-guided Design of a High Affinity Dual Specificity Antibody to Target Two Angiogenic Factors in Neovascular Age-related Macular Degeneration.

PubMed

Koenig, Patrick; Lee, Chingwei V; Sanowar, Sarah; Wu, Ping; Stinson, Jeremy; Harris, Seth F; Fuh, Germaine

2015-09-04

The development of dual targeting antibodies promises therapies with improved efficacy over mono-specific antibodies. Here, we engineered a Two-in-One VEGF/angiopoietin 2 antibody with dual action Fab (DAF) as a potential therapeutic for neovascular age-related macular degeneration. Crystal structures of the VEGF/angiopoietin 2 DAF in complex with its two antigens showed highly overlapping binding sites. To achieve sufficient affinity of the DAF to block both angiogenic factors, we turned to deep mutational scanning in the complementarity determining regions (CDRs). By mutating all three CDRs of each antibody chain simultaneously, we were able not only to identify affinity improving single mutations but also mutation pairs from different CDRs that synergistically improve both binding functions. Furthermore, insights into the cooperativity between mutations allowed us to identify fold-stabilizing mutations in the CDRs. The data obtained from deep mutational scanning reveal that the majority of the 52 CDR residues are utilized differently for the two antigen binding function and permit, for the first time, the engineering of several DAF variants with sub-nanomolar affinity against two structurally unrelated antigens. The improved variants show similar blocking activity of receptor binding as the high affinity mono-specific antibodies against these two proteins, demonstrating the feasibility of generating a dual specificity binding surface with comparable properties to individual high affinity mono-specific antibodies. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Novel Targeted Therapies for Inflammatory Breast Cancer

DTIC Science & Technology

2017-10-01

AWARD NUMBER: W81XWH-16-1-0461 TITLE: Novel Targeted Therapies for Inflammatory Breast Cancer PRINCIPAL INVESTIGATOR: Jose Silva CONTRACTING...CONTRACT NUMBER Novel Targeted Therapies for Inflammatory Breast Cancer 5b. GRANT NUMBER W81XWH-16-1-0461 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) l 5d...NOTES 14. ABSTRACT Inflammatory breast cancer (IBC, ~5% of all breast cancers ) is the most lethal form of breast cancer , presenting a 5- year

Requests Cancer Targets for Monoclonal Antibody Production and Characterization | Office of Cancer Clinical Proteomics Research

Cancer.gov

In an effort to provide well-characterized monoclonal antibodies to the scientific community, the National Cancer Institute (NCI) Antibody Characterization Program requests cancer-related protein targets for affinity production and distribution. The program from The Office of Cancer Clinical Proteomics Research provides reagents and other critical resources that support protein and/or peptide measurements and analysis.

Targeted therapies for the treatment of leukemia.

PubMed

Stull, Dawn Marie

2003-05-01

To review novel targeted therapies for the treatment of leukemia. Professional journals, books, and government publications. Nonspecific cytotoxic chemotherapeutic agents provide marginal therapeutic benefit and significant toxicity when used in the treatment of leukemia. There is a tremendous need for new therapies with increased efficacy and decreased adverse effects. Advances in molecular science, genetics, and immunology, along with improved laboratory technology, have led to the discovery of unique targets integral to the growth and proliferation of malignant cells which are providing the foundation for the development of a new generation of antitumor agents. Nurses must be prepared to educate patients, administer novel therapies, and manage side effects.

Aligning physics and physiology: Engineering antibodies for radionuclide delivery.

PubMed

Tsai, Wen-Ting K; Wu, Anna M

2018-03-14

The exquisite specificity of antibodies and antibody fragments renders them excellent agents for targeted delivery of radionuclides. Radiolabeled antibodies and fragments have been successfully used for molecular imaging and radioimmunotherapy (RIT) of cell surface targets in oncology and immunology. Protein engineering has been used for antibody humanization essential for clinical applications, as well as optimization of important characteristics including pharmacokinetics, biodistribution, and clearance. Although intact antibodies have high potential as imaging and therapeutic agents, challenges include long circulation time in blood, which leads to later imaging time points post-injection and higher blood absorbed dose that may be disadvantageous for RIT. Using engineered fragments may address these challenges, as size reduction and removal of Fc function decreases serum half-life. Radiolabeled fragments and pretargeting strategies can result in high contrast images within hours to days, and a reduction of RIT toxicity in normal tissues. Additionally, fragments can be engineered to direct hepatic or renal clearance, which may be chosen based on the application and disease setting. This review discusses aligning the physical properties of radionuclides (positron, gamma, beta, alpha, and Auger emitters) with antibodies and fragments and highlights recent advances of engineered antibodies and fragments in preclinical and clinical development for imaging and therapy. Copyright © 2018 John Wiley & Sons, Ltd.

Changing strategies for target therapy in gastric cancer.

PubMed

Lee, Suk-Young; Oh, Sang Cheul

2016-01-21

In spite of a worldwide decrease in the incidence of gastric cancer, this malignancy still remains one of the leading causes of cancer mortality. Great efforts have been made to improve treatment outcomes in patients with metastatic gastric cancer, and the introduction of trastuzumab has greatly improved the overall survival. The trastuzumab treatment took its first step in opening the era of molecular targeted therapy, however several issues still need to be resolved to increase the efficacy of targeted therapy. Firstly, many patients with metastatic gastric cancer who receive trastuzumab in combination with chemotherapeutic agents develop resistance to the targeted therapy. Secondly, many clinical trials testing novel molecular targeted agents with demonstrated efficacy in other malignancies have failed to show benefit in patients with metastatic gastric cancer, suggesting the importance of the selection of appropriate indications according to molecular characteristics in application of targeted agents. Herein, we review the molecular targeted agents currently approved and in use, and clinical trials in patients with metastatic gastric cancer, and demonstrate the limitations and future direction in treatment of advanced gastric cancer.

Enterolactone glucuronide and β-glucuronidase in antibody directed enzyme prodrug therapy for targeted prostate cancer cell treatment.

PubMed

Di, Yunyun; Ji, Shaoping; Wolf, Philipp; Krol, Ed S; Alcorn, Jane

2017-08-01

Evidence from preclinical and animal studies demonstrated an anticancer effect of flaxseed lignans, particularly enterolactone (ENL), against prostate cancer. However, extensive first-pass metabolism following oral lignan consumption results in their systemic availability primarily as glucuronic acid conjugates (ENL-Gluc) and their modest in vivo effects. To overcome the unfavorable pharmacokinetics and improve their effectiveness in prostate cancer, antibody-directed enzyme prodrug therapy (ADEPT) might offer a novel strategy to allow for restricted activation of ENL from circulating ENL-Gluc within the tumor environment. The anti-prostate-specific membrane antigen (PSMA) antibody D7 was fused with human β-glucuronidase (hβG) via a flexible linker. The binding property of the fusion construct, D7-hβG, against purified or cell surface PSMA was determined by flow cytometry and Octet Red 384 system, respectively, with a binding rate constant, K d, of 2.5 nM. The enzymatic activity of D7-hβG was first tested using the probe, 4-methylumbelliferone glucuronide. A 3.8-fold greater fluorescence intensity was observed at pH 4.5 at 2 h compared with pH 7.4. The ability of D7-hβG to activate ENL from ENL-Gluc was tested and detected using LC-MS/MS. Enhanced generation of ENL was observed with increasing ENL-Gluc concentrations and reached 3613.2 ng/mL following incubation with 100 μM ENL-Gluc at pH 4.5 for 0.5 h. D7-hβG also decreased docetaxel IC 50 value from 23 nM to 14.9 nM in C4-2 cells. These results confirmed the binding and activity of D7-hβG and additional in vitro investigation is needed to support the future possibility of introducing this ADEPT system to animal models.

In vivo Therapy with Monoclonal Anti-I-A Antibody Suppresses Immune Responses to Acetylcholine Receptor

NASA Astrophysics Data System (ADS)

Waldor, Matthew K.; Sriram, Subramaniam; McDevitt, Hugh O.; Steinman, Lawrence

1983-05-01

A monoclonal antibody to I-A gene products of the immune response gene complex attenuates both humoral and cellular responses to acetylcholine receptor and appears to suppress clinical manifestations of experimental autoimmune myasthenia gravis. This demonstrates that use of antibodies against immune response gene products that are associated with susceptibility to disease may be feasible for therapy in autoimmune conditions such as myasthenia gravis.

Systemic p53 gene therapy of cancer with immunolipoplexes targeted by anti-transferrin receptor scFv.

PubMed Central

Xu, L.; Tang, W. H.; Huang, C. C.; Alexander, W.; Xiang, L. M.; Pirollo, K. F.; Rait, A.; Chang, E. H.

2001-01-01

BACKGROUND: A long-standing goal in genetic therapy for cancer is a systemic gene delivery system that selectively targets tumor cells, including metastases. Here we describe a novel cationic immunolipoplex system that shows high in vivo gene transfer efficiency and anti- tumor efficacy when used for systemic p53 gene therapy of cancer. MATERIALS AND METHODS: A cationic immunolipoplex incorporating a biosynthetically lipid-tagged, anti-transferrin receptor single-chain antibody (TfRscFv), was designed to target tumor cells both in vitro and in vivo. A human breast cancer metastasis model was employed to evaluate the in vivo efficacy of systemically administered, TfRscFv-immunolipoplex-mediated, p53 gene therapy in combination with docetaxel. RESULTS: The TfRscFv-targeting cationic immunolipoplex had a size of 60-100 nm, showed enhanced tumor cell binding, and improved targeted gene delivery and transfection efficiencies, both in vitro and in vivo. The p53 tumor suppressor gene was not only systemically delivered by the immunolipoplex to human tumor xenografts in nude mice but also functionally expressed. In the nude mouse breast cancer metastasis model, the combination of the p53 gene delivered by the systemic administration of the TfRscFv-immunolipoplex and docetaxel resulted in significantly improved efficacy with prolonged survival. CONCLUSIONS: This is the first report using scFv-targeting immunolipoplexes for systemic gene therapy. The TfRscFv has a number of advantages over the transferrin (Tf) molecule itself: (1) scFv has a much smaller size than Tf producing a smaller immunolipoplex giving better penetration into solid tumors; (2) unlike Tf, the scFv is a recombinant protein, not a blood product; (3) large scale production and strict quality control of the recombinant scFv, as well as scFv-immunolipoplex, are feasible. The sensitization of tumors to chemotherapy by this tumor-targeted and efficient p53 gene delivery method could lower the effective dose of

Antibodies Specifically Targeting a Locally Misfolded Region of Tumor Associated EGFR

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

Garrett, T.; Burgess, A; Gan, H

2009-01-01

Epidermal Growth Factor Receptor (EGFR) is involved in stimulating the growth of many human tumors, but the success of therapeutic agents has been limited in part by interference from the EGFR on normal tissues. Previously, we reported an antibody (mab806) against a truncated form of EGFR found commonly in gliomas. Remarkably, it also recognizes full-length EGFR on tumor cells but not on normal cells. However, the mechanism for this activity was unclear. Crystallographic structures for Fab:EGFR{sub 287-302} complexes of mAb806 (and a second, related antibody, mAb175) show that this peptide epitope adopts conformations similar to those found in the wtEGFR.more » However, in both conformations observed for wtEGFR, tethered and untethered, antibody binding would be prohibited by significant steric clashes with the CR1 domain. Thus, these antibodies must recognize a cryptic epitope in EGFR. Structurally, it appeared that breaking the disulfide bond preceding the epitope might allow the CR1 domain to open up sufficiently for antibody binding. The EGFR{sub C271A/C283A} mutant not only binds mAb806, but binds with 1:1 stoichiometry, which is significantly greater than wtEGFR binding. Although mAb806 and mAb175 decrease tumor growth in xenografts displaying mutant, overexpressed, or autocrine stimulated EGFR, neither antibody inhibits the in vitro growth of cells expressing wtEGFR. In contrast, mAb806 completely inhibits the ligand-associated stimulation of cells expressing EGFR{sub C271A/C283A}. Clearly, the binding of mAb806 and mAb175 to the wtEGFR requires the epitope to be exposed either during receptor activation, mutation, or overexpression. This mechanism suggests the possibility of generating antibodies to target other wild-type receptors on tumor cells.« less

Targeted therapy for non-small cell lung cancer: current standards and the promise of the future

PubMed Central

Chan, Bryan A.

2015-01-01

In recent years, there has been a major paradigm shift in the management of non-small cell lung cancer (NSCLC). NSCLC should now be further sub-classified by histology and driver mutation if one is known or present. Translational research advances now allow such mutations to be inhibited by either receptor monoclonal antibodies (mAb) or small molecule tyrosine kinase inhibitors (TKI). Whilst empirical chemotherapy with a platinum-doublet remains the gold standard for advanced NSCLC without a known driver mutation, targeted therapy is pushing the boundary to significantly improve patient outcomes and quality of life. In this review, we will examine the major subtypes of oncogenic drivers behind NSCLC as well as the development of targeted agents available to treat them both now and in the foreseeable future. PMID:25806345

Conserved and Variant Epitopes of Plasmodium vivax Duffy Binding Protein as Targets of Inhibitory Monoclonal Antibodies

PubMed Central

Ntumngia, Francis B.; Schloegel, Jesse; Barnes, Samantha J.; McHenry, Amy M.; Singh, Sanjay; King, Christopher L.

2012-01-01

The Duffy binding protein (DBP) is a vital ligand for Plasmodium vivax blood-stage merozoite invasion, making the molecule an attractive vaccine candidate against vivax malaria. Similar to other blood-stage vaccine candidates, DBP allelic variation eliciting a strain-specific immunity may be a major challenge for development of a broadly effective vaccine against vivax malaria. To understand whether conserved epitopes can be the target of neutralizing anti-DBP inhibition, we generated a set of monoclonal antibodies to DBP and functionally analyzed their reactivity to a panel of allelic variants. Quantitative analysis by enzyme-linked immunosorbent assay (ELISA) determined that some monoclonal antibodies reacted strongly with epitopes conserved on all DBP variants tested, while reactivity of others was allele specific. Qualitative analysis characterized by anti-DBP functional inhibition using an in vitro erythrocyte binding inhibition assay indicated that there was no consistent correlation between the endpoint titers and functional inhibition. Some monoclonal antibodies were broadly inhibitory while inhibition of others varied significantly by target allele. These data demonstrate a potential for vaccine-elicited immunization to target conserved epitopes but optimization of DBP epitope target specificity and immunogenicity may be necessary for protection against diverse P. vivax strains. PMID:22215740

Conserved and variant epitopes of Plasmodium vivax Duffy binding protein as targets of inhibitory monoclonal antibodies.

PubMed

Ntumngia, Francis B; Schloegel, Jesse; Barnes, Samantha J; McHenry, Amy M; Singh, Sanjay; King, Christopher L; Adams, John H

2012-03-01

The Duffy binding protein (DBP) is a vital ligand for Plasmodium vivax blood-stage merozoite invasion, making the molecule an attractive vaccine candidate against vivax malaria. Similar to other blood-stage vaccine candidates, DBP allelic variation eliciting a strain-specific immunity may be a major challenge for development of a broadly effective vaccine against vivax malaria. To understand whether conserved epitopes can be the target of neutralizing anti-DBP inhibition, we generated a set of monoclonal antibodies to DBP and functionally analyzed their reactivity to a panel of allelic variants. Quantitative analysis by enzyme-linked immunosorbent assay (ELISA) determined that some monoclonal antibodies reacted strongly with epitopes conserved on all DBP variants tested, while reactivity of others was allele specific. Qualitative analysis characterized by anti-DBP functional inhibition using an in vitro erythrocyte binding inhibition assay indicated that there was no consistent correlation between the endpoint titers and functional inhibition. Some monoclonal antibodies were broadly inhibitory while inhibition of others varied significantly by target allele. These data demonstrate a potential for vaccine-elicited immunization to target conserved epitopes but optimization of DBP epitope target specificity and immunogenicity may be necessary for protection against diverse P. vivax strains.

Antihyperlipidemic therapies targeting PCSK9.

PubMed

Weinreich, Michael; Frishman, William H

2014-01-01

Hyperlipidemia is a major cause of cardiovascular disease despite the availability of first-line cholesterol-lowering agents such as statins. A new therapeutic approach to lowering low-density lipoprotein-cholesterol (LDL-C) acts by blocking LDL-receptor degradation by serum proprotein convertase subtilisin kexin 9 (PCSK9). Human monoclonal antibodies that target PCSK9 and its interaction with the LDL receptor are now in clinical trials (REGN727/SAR23653, AMG145, and RN316). These agents are administered by either subcutaneous or intravenous routes, and have been shown to have major LDL-C and apolipoprotein B effects when combined with statins. A phase III clinical trial program evaluating clinical endpoints is now in progress. Other PCSK9-targeted approaches are in early stages of investigation, including natural inhibitors of PCSK9, RNA interference, and antisense inhibitors.

Early antibiotic administration but not antibody therapy directed against IL-6 improves survival in septic mice predicted to die based upon high IL-6 levels

PubMed Central

Vyas, Dinesh; Javadi, Pardis; DiPasco, Peter J; Buchman, Timothy G; Hotchkiss, Richard S; Coopersmith, Craig M

2005-01-01

Elevated interleukin (IL)-6 levels correlate with increased mortality following sepsis. IL-6 levels >14,000 pg/ml drawn 6 hours following cecal ligation and puncture (CLP) are associated with 100% mortality in ND4 mice, even if antibiotic therapy is initiated 12 hours after the septic insult. The first aim of this study was to see if earlier institution of antibiotic therapy could improve overall survival in septic mice and rescue the subset of animals predicted to die based upon high IL-6 levels. Mice (n=184) were subjected to CLP, had IL-6 levels drawn six hours later and then were randomized to receive imipenem, a broad spectrum antimicrobial agent, beginning six or twelve hours post-operatively. Overall one-week survival improved from 25.5% to 35.9% with earlier administration of antibiotics (p<0.05). In mice with IL-6 levels >14,000 pg/ml, 25% survived if imipenem was started at 6 hours, while none survived if antibiotics were started later (p<0.05). Based upon these results, we examined whether targeted antibody therapy could improve survival in mice with elevated IL-6 levels. A different cohort of mice (n=54) had their blood drawn six hours after CLP and then were randomized to receive either monoclonal anti-IL-6 IgG or irrelevant rat IgG. Anti-IL-6 antibody failed to improve either overall survival or outcome in mice with IL-6 levels >14,000 pg/ml. These results demonstrate that earlier systemic therapy can improve outcome in a subset of mice predicted to die in sepsis, but we are unable to demonstrate any benefit in similar animals using targeted therapy directed at IL-6. PMID:15947070

A "Trojan horse" bispecific-antibody strategy for broad protection against ebolaviruses.

PubMed

Wec, Anna Z; Nyakatura, Elisabeth K; Herbert, Andrew S; Howell, Katie A; Holtsberg, Frederick W; Bakken, Russell R; Mittler, Eva; Christin, John R; Shulenin, Sergey; Jangra, Rohit K; Bharrhan, Sushma; Kuehne, Ana I; Bornholdt, Zachary A; Flyak, Andrew I; Saphire, Erica Ollmann; Crowe, James E; Aman, M Javad; Dye, John M; Lai, Jonathan R; Chandran, Kartik

2016-10-21

There is an urgent need for monoclonal antibody (mAb) therapies that broadly protect against Ebola virus and other filoviruses. The conserved, essential interaction between the filovirus glycoprotein, GP, and its entry receptor Niemann-Pick C1 (NPC1) provides an attractive target for such mAbs but is shielded by multiple mechanisms, including physical sequestration in late endosomes. Here, we describe a bispecific-antibody strategy to target this interaction, in which mAbs specific for NPC1 or the GP receptor-binding site are coupled to a mAb against a conserved, surface-exposed GP epitope. Bispecific antibodies, but not parent mAbs, neutralized all known ebolaviruses by coopting viral particles themselves for endosomal delivery and conferred postexposure protection against multiple ebolaviruses in mice. Such "Trojan horse" bispecific antibodies have potential as broad antifilovirus immunotherapeutics. Copyright © 2016, American Association for the Advancement of Science.

The Role of Anti-Drug Antibodies in the Pharmacokinetics, Disposition, Target Engagement, and Efficacy of a GITR Agonist Monoclonal Antibody in Mice.

PubMed

Brunn, Nicholas D; Mauze, Smita; Gu, Danling; Wiswell, Derek; Ueda, Roanna; Hodges, Douglas; Beebe, Amy M; Zhang, Shuli; Escandón, Enrique

2016-03-01

Administration of biologics to enhance T-cell function is part of a rapidly growing field of cancer immunotherapy demonstrated by the unprecedented clinical success of several immunoregulatory receptor targeting antibodies. While these biologic agents confer significant anti-tumor activity through targeted immune response modulation, they can also elicit broad immune responses potentially including the production of anti-drug antibodies (ADAs). DTA-1, an agonist monoclonal antibody against GITR, is a highly effective anti-tumor treatment in preclinical models. We demonstrate that repeated dosing with murinized DTA-1 (mDTA-1) generates ADAs with corresponding reductions in drug exposure and engagement of GITR on circulating CD3(+) CD4(+) T cells, due to rapid hepatic drug uptake and catabolism. Mice implanted with tumors after induction of preexisting mDTA-1 ADA show no anti-tumor efficacy when given 3 mg/kg mDTA-1, an efficacious dose in naive mice. Nonetheless, increasing mDTA-1 treatment to 30 mg/kg in ADA-positive mice restores mDTA-1 exposure and GITR engagement on circulating CD3(+) CD4(+) T cells, thereby partially restoring anti-tumor efficacy. Formation of anti-mDTA-1 antibodies and changes in drug exposure and disposition does not occur in GITR(-/-) mice, consistent with a role for GITR agonism in humoral immunity. Finally, the administration of muDX400, a murinized monoclonal antibody against the checkpoint inhibitor PD-1, dosed alone or combined with mDTA-1 did not result in reduced muDX400 exposure, nor did it change the nature of the anti-mDTA-1 response. This indicates that anti-GITR immunogenicity may not necessarily impact the pharmacology of coadministered monoclonal antibodies, supporting combination immunomodulatory strategies. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

A Modeling and Experimental Investigation of the Effects of Antigen Density, Binding Affinity, and Antigen Expression Ratio on Bispecific Antibody Binding to Cell Surface Targets*

PubMed Central

Rhoden, John J.; Dyas, Gregory L.

2016-01-01

Despite the increasing number of multivalent antibodies, bispecific antibodies, fusion proteins, and targeted nanoparticles that have been generated and studied, the mechanism of multivalent binding to cell surface targets is not well understood. Here, we describe a conceptual and mathematical model of multivalent antibody binding to cell surface antigens. Our model predicts that properties beyond 1:1 antibody:antigen affinity to target antigens have a strong influence on multivalent binding. Predicted crucial properties include the structure and flexibility of the antibody construct, the target antigen(s) and binding epitope(s), and the density of antigens on the cell surface. For bispecific antibodies, the ratio of the expression levels of the two target antigens is predicted to be critical to target binding, particularly for the lower expressed of the antigens. Using bispecific antibodies of different valencies to cell surface antigens including MET and EGF receptor, we have experimentally validated our modeling approach and its predictions and observed several nonintuitive effects of avidity related to antigen density, target ratio, and antibody affinity. In some biological circumstances, the effect we have predicted and measured varied from the monovalent binding interaction by several orders of magnitude. Moreover, our mathematical framework affords us a mechanistic interpretation of our observations and suggests strategies to achieve the desired antibody-antigen binding goals. These mechanistic insights have implications in antibody engineering and structure/activity relationship determination in a variety of biological contexts. PMID:27022022

A Modeling and Experimental Investigation of the Effects of Antigen Density, Binding Affinity, and Antigen Expression Ratio on Bispecific Antibody Binding to Cell Surface Targets.

PubMed

Rhoden, John J; Dyas, Gregory L; Wroblewski, Victor J

2016-05-20

Despite the increasing number of multivalent antibodies, bispecific antibodies, fusion proteins, and targeted nanoparticles that have been generated and studied, the mechanism of multivalent binding to cell surface targets is not well understood. Here, we describe a conceptual and mathematical model of multivalent antibody binding to cell surface antigens. Our model predicts that properties beyond 1:1 antibody:antigen affinity to target antigens have a strong influence on multivalent binding. Predicted crucial properties include the structure and flexibility of the antibody construct, the target antigen(s) and binding epitope(s), and the density of antigens on the cell surface. For bispecific antibodies, the ratio of the expression levels of the two target antigens is predicted to be critical to target binding, particularly for the lower expressed of the antigens. Using bispecific antibodies of different valencies to cell surface antigens including MET and EGF receptor, we have experimentally validated our modeling approach and its predictions and observed several nonintuitive effects of avidity related to antigen density, target ratio, and antibody affinity. In some biological circumstances, the effect we have predicted and measured varied from the monovalent binding interaction by several orders of magnitude. Moreover, our mathematical framework affords us a mechanistic interpretation of our observations and suggests strategies to achieve the desired antibody-antigen binding goals. These mechanistic insights have implications in antibody engineering and structure/activity relationship determination in a variety of biological contexts. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Targeting to cells of fluorescent liposomes covalently coupled with monoclonal antibody or protein A

NASA Astrophysics Data System (ADS)

Leserman, Lee D.; Barbet, Jacques; Kourilsky, François; Weinstein, John N.

1980-12-01

Many applications envisioned for liposomes in cell biology and chemotherapy require their direction to specific cellular targets1-3. The ability to use antibody as a means of conferring specificity to liposomes would markedly increase their usefulness. We report here a method for covalently coupling soluble proteins, including monoclonal antibody and Staphylococcus aureus protein A (ref. 4), to small sonicated liposomes, by using the heterobifunctional cross-linking reagent N-hydroxysuccinimidyl 3-(2-pyridyldithio)propionate (SPDP, Pharmacia). Liposomes bearing covalently coupled mouse monoclonal antibody against human β2-microglobulin [antibody B1.1G6 (IgG2a, κ) (B. Malissen et al., in preparation)] bound specifically to human, but not to mouse cells. Liposomes bearing protein A became bound to human cells previously incubated with the B1.1G6 antibody, but not to cells incubated without antibody. The coupling method results in efficient binding of protein to the liposomes without aggregation and without denaturation of the coupled ligand; at least 60% of liposomes bound functional protein. Further, liposomes did not leak encapsulated carboxyfluorescein (CF) as a consequence of the reaction.

Self-assembling complexes of quantum dots and scFv antibodies for cancer cell targeting and imaging.

PubMed

Zdobnova, Tatiana A; Stremovskiy, Oleg A; Lebedenko, Ekaterina N; Deyev, Sergey M

2012-01-01

Semiconductor quantum dots represent a novel class of fluorophores with unique physical and chemical properties which could enable a remarkable broadening of the current applications of fluorescent imaging and optical diagnostics. Complexes of quantum dots and antibodies are promising visualising agents for fluorescent detection of selective biomarkers overexpressed in tumor tissues. Here we describe the construction of self-assembling fluorescent complexes of quantum dots and anti-HER1 or anti-HER2/neu scFv antibodies and their interactions with cultured tumor cells. A binding strategy based on a very specific non-covalent interaction between two proteins, barnase and barstar, was used to connect quantum dots and the targeting antibodies. Such a strategy allows combining the targeting and visualization functions simply by varying the corresponding modules of the fluorescent complex.

Self-Assembling Complexes of Quantum Dots and scFv Antibodies for Cancer Cell Targeting and Imaging

PubMed Central

Zdobnova, Tatiana A.; Stremovskiy, Oleg A.; Lebedenko, Ekaterina N.; Deyev, Sergey M.

2012-01-01

Semiconductor quantum dots represent a novel class of fluorophores with unique physical and chemical properties which could enable a remarkable broadening of the current applications of fluorescent imaging and optical diagnostics. Complexes of quantum dots and antibodies are promising visualising agents for fluorescent detection of selective biomarkers overexpressed in tumor tissues. Here we describe the construction of self-assembling fluorescent complexes of quantum dots and anti-HER1 or anti-HER2/neu scFv antibodies and their interactions with cultured tumor cells. A binding strategy based on a very specific non-covalent interaction between two proteins, barnase and barstar, was used to connect quantum dots and the targeting antibodies. Such a strategy allows combining the targeting and visualization functions simply by varying the corresponding modules of the fluorescent complex. PMID:23133578

HER2 expression in breast cancer cells is downregulated upon active targeting by antibody-engineered multifunctional nanoparticles in mice.

PubMed

Corsi, Fabio; Fiandra, Luisa; De Palma, Clara; Colombo, Miriam; Mazzucchelli, Serena; Verderio, Paolo; Allevi, Raffaele; Tosoni, Antonella; Nebuloni, Manuela; Clementi, Emilio; Prosperi, Davide

2011-08-23

Subcellular destiny of targeted nanoparticles in cancer cells within living organisms is still an open matter of debate. By in vivo and ex vivo experiments on tumor-bearing mice treated with antibody-engineered magnetofluorescent nanocrystals, in which we combined fluorescence imaging, magnetic relaxation, and trasmission electron microscopy approaches, we provide evidence that nanoparticles are effectively delivered to the tumor by active targeting. These nanocrystals were demonstrated to enable contrast enhancement of the tumor in magnetic resonance imaging. In addition, we were able to discriminate between the fate of the organic corona and the metallic core upon cell internalization. Accurate immunohistochemical analysis confirmed that hybrid nanoparticle endocytosis is mediated by the complex formation with HER2 receptor, leading to a substantial downregulation of HER2 protein expression on the cell surface. These results provide a direct insight into the pathway of internalization and degradation of targeted hybrid nanoparticles in cancer cells in vivo and suggest a potential application of this immunotheranostic nanoagent in neoadjuvant therapy of cancer. © 2011 American Chemical Society

Uncovering the Origin of Skin Side Effects from EGFR-Targeted Therapies | Center for Cancer Research

Cancer.gov

The epidermal growth factor receptor (EGFR), a key regulator of cell proliferation, is often mutated or overexpressed in a variety of cancer types. EGFR-targeted therapies, including monoclonal antibodies and small molecule inhibitors, can effectively treat patients whose tumors depend on aberrant EGFR signaling. Within a few weeks of initiating therapy, however, patients develop a characteristic rash with leukocyte infiltration into the skin accompanied by pruritus (itching), scaling of the skin, hair loss, and even changes in skin cell differentiation. The side effects can become so severe that patients take reduced doses, which can limit efficacy, or stop treatment altogether. To understand how EGFR inhibitors cause these skin changes in the hopes of identifying a means of preventing them, Stuart Yuspa, M.D., of CCR’s Laboratory of Cancer Biology and Genetics, and his colleagues examined patient samples and generated a mouse model of EGFR loss in the skin.

Immunotherapy Targets in Pediatric Cancer

PubMed Central

Orentas, Rimas J.; Lee, Daniel W.; Mackall, Crystal

2011-01-01

Immunotherapy for cancer has shown increasing success and there is ample evidence to expect that progress gleaned in immune targeting of adult cancers can be translated to pediatric oncology. This manuscript reviews principles that guide selection of targets for immunotherapy of cancer, emphasizing the similarities and distinctions between oncogene-inhibition targets and immune targets. It follows with a detailed review of molecules expressed by pediatric tumors that are already under study as immune targets or are good candidates for future studies of immune targeting. Distinctions are made between cell surface antigens that can be targeted in an MHC independent manner using antibodies, antibody derivatives, or chimeric antigen receptors versus intracellular antigens which must be targeted with MHC restricted T cell therapies. Among the most advanced immune targets for childhood cancer are CD19 and CD22 on hematologic malignancies, GD2 on solid tumors, and NY-ESO-1 expressed by a majority of synovial sarcomas, but several other molecules reviewed here also have properties which suggest that they too could serve as effective targets for immunotherapy of childhood cancer. PMID:22645714

Controversies in targeted therapy of adult T cell leukemia/lymphoma: ON target or OFF target effects?

PubMed

Nasr, Rihab; El Hajj, Hiba; Kfoury, Youmna; de Thé, Hugues; Hermine, Olivier; Bazarbachi, Ali

2011-06-01

Adult T cell leukemia/lymphoma (ATL) represents an ideal model for targeted therapy because of intrinsic chemo-resistance of ATL cells and the presence of two well identified targets: the HTLV-I retrovirus and the viral oncoprotein Tax. The combination of zidovudine (AZT) and interferon-alpha (IFN) has a dramatic impact on survival of ATL patients. Although the mechanism of action remains unclear, arguments in favor or against a direct antiviral effect will be discussed. Yet, most patients relapse and alternative therapies are mandatory. IFN and arsenic trioxide induce Tax proteolysis, synergize to induce apoptosis in ATL cells and cure Tax-driven ATL in mice through specific targeting of leukemia initiating cell activity. These results provide a biological basis for the clinical success of arsenic/IFN/AZT therapy in ATL patients and suggest that both extinction of viral replication (AZT) and Tax degradation (arsenic/IFN) are needed to cure ATL.

Recombinant human antibody fragment against tetanus toxoid produced by phage display

PubMed Central

Neelakantam, B.; Sridevi, N. V.; Shukra, A. M.; Sugumar, P.; Samuel, S.

2014-01-01

Phage display technology is a powerful in vitro method for the identification of specific monoclonal antibodies (antibody fragments) to an antigenic target and allows the rapid generation and selection of high affinity, fully human antibodies directed toward any disease target appropriate for antibody therapy. In the present study, we exploited the phage display technology for the selection of an antigen binding fragment (Fabs) toward tetanus toxoid using human naïve phage antibody library constructed from peripheral blood lymphocytes of naïve human donors. The phages displaying Fab were subjected to three rounds of bio-panning with tetanus toxoid as antigen on a solid phase. The high affinity antibody fragments were expressed in HB2151 strain of Escherichia coli and purified by immobilized metal affinity chromatography. The binding activity and specificity of the antibody fragment was established by its reactivity toward tetanus toxoid and non-reactivity toward other related toxins as determined by enzyme-linked immunosorbent assay and immunoblot analysis. The selected Fab fragment forming the antigen-binding complexes with the toxoid in flocculation assay indicates that the Fab may have a potential neutralizing ability toward antigen. PMID:24678405

Recombinant human antibody fragment against tetanus toxoid produced by phage display.

PubMed

Neelakantam, B; Sridevi, N V; Shukra, A M; Sugumar, P; Samuel, S; Rajendra, L

2014-03-01

Phage display technology is a powerful in vitro method for the identification of specific monoclonal antibodies (antibody fragments) to an antigenic target and allows the rapid generation and selection of high affinity, fully human antibodies directed toward any disease target appropriate for antibody therapy. In the present study, we exploited the phage display technology for the selection of an antigen binding fragment (Fabs) toward tetanus toxoid using human naïve phage antibody library constructed from peripheral blood lymphocytes of naïve human donors. The phages displaying Fab were subjected to three rounds of bio-panning with tetanus toxoid as antigen on a solid phase. The high affinity antibody fragments were expressed in HB2151 strain of Escherichia coli and purified by immobilized metal affinity chromatography. The binding activity and specificity of the antibody fragment was established by its reactivity toward tetanus toxoid and non-reactivity toward other related toxins as determined by enzyme-linked immunosorbent assay and immunoblot analysis. The selected Fab fragment forming the antigen-binding complexes with the toxoid in flocculation assay indicates that the Fab may have a potential neutralizing ability toward antigen.

A novel antibody-drug conjugate targeting SAIL for the treatment of hematologic malignancies.

PubMed

Kim, S Y; Theunissen, J-W; Balibalos, J; Liao-Chan, S; Babcock, M C; Wong, T; Cairns, B; Gonzalez, D; van der Horst, E H; Perez, M; Levashova, Z; Chinn, L; D'Alessio, J A; Flory, M; Bermudez, A; Jackson, D Y; Ha, E; Monteon, J; Bruhns, M F; Chen, G; Migone, T-S

2015-05-29

Although several new therapeutic approaches have improved outcomes in the treatment of hematologic malignancies, unmet need persists in acute myeloid leukemia (AML), multiple myeloma (MM) and non-Hodgkin's lymphoma. Here we describe the proteomic identification of a novel cancer target, SAIL (Surface Antigen In Leukemia), whose expression is observed in AML, MM, chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). While SAIL is widely expressed in CLL, AML, MM, DLBCL and FL patient samples, expression in cancer cell lines is mostly limited to cells of AML origin. We evaluated the antitumor activity of anti-SAIL monoclonal antibodies, 7-1C and 67-7A, conjugated to monomethyl auristatin F. Following internalization, anti-SAIL antibody-drug conjugates (ADCs) exhibited subnanomolar IC50 values against AML cell lines in vitro. In pharmacology studies employing AML cell line xenografts, anti-SAIL ADCs resulted in significant tumor growth inhibition. The restricted expression profile of this target in normal tissues, the high prevalence in different types of hematologic cancers and the observed preclinical activity support the clinical development of SAIL-targeted ADCs.

Recent Advances in Targeted Therapy for Glioma.