title: Anti-angiogenic cancer therapy based on integrin alphavbeta3 antagonism.
abstract: Angiogenesis, the formation of new blood vessels from pre-existing vasculature, is a fundamental process during cancer progression. Anti-angiogenic strategies have been pursued for cancer treatment and prevention of cancer recurrence and metastasis. Integrins are a family of cell adhesion molecules consisting of two non-covalently bound transmembrane subunits (alpha and beta). Much research has demonstrated that integrin signaling plays a key role in tumor angiogenesis and metastasis. Integrin alphavbeta3 is highly expressed on activated endothelial cells and tumor cells but is not present in resting endothelial cells and most normal organ systems, which makes it a suitable target for anti-angiogenic cancer therapy. In this review we will focus on cancer therapy targeting integrin alphavbeta3 while other integrins (such as alpha5beta1, alphaIIbbeta3, alphavbeta5, alpha6beta4) will only be briefly mentioned when relevant. MEDI-522 (a humanized anti-human integrin alphavbeta3 monoclonal antibody) and Cilengitide (cyclic peptidic integrin alphavbeta3/alphavbeta5 antagonist) are currently in clinical trials for anti-angiogenic cancer therapy. Small interfering RNA (siRNA) that specifically silences integrin alphav and/or beta3 was reported to cause tumor shrinkage in preclinical xenograft models. Combination of anti-integrin alphavbeta3 therapy and other therapeutic approaches (such as chemotherapy, radiotherapy and gene therapy) has also been applied for cancer treatment. Mounting evidence suggests that there is potentially synergistic effect of combined therapeutic approaches over single modality alone. Lastly, integrin targeted delivery (drugs, genes, and radioisotopes) and imaging (optical, MRI, ultrasound, SPECT, and PET) is discussed in detail.
authors.affiliation: Molecular Imaging Program at Stanford, Department of Radiology and Bio-X Program, Stanford University School of Medicine, Stanford, CA 94305-5484, USA.
authors.forename: Weibo
authors.initials: W
authors.lastname: Cai
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Chen
mesh_terms: D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D003131:Combined Modality Therapy; D019483:Disintegrins / Q000627:therapeutic use; D016503:Drug Delivery Systems; D020868:Gene Silencing / Q000187:drug effects; D018390:Gene Targeting; D006801:Humans; D039302:Integrin alphaVbeta3 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000276:immunology; D008279:Magnetic Resonance Imaging; D009369:Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging / Q000188:drug therapy*; D009842:Oligopeptides / Q000627:therapeutic use; D049268:Positron-Emission Tomography; D034741:RNA, Small Interfering / Q000494:pharmacology; D012910:Snake Venoms / Q000627:therapeutic use; D015899:Tomography, Emission-Computed, Single-Photon; D014463:Ultrasonography
chemical_list: D020533:Angiogenesis Inhibitors; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D019483:Disintegrins; D039302:Integrin alphaVbeta3; D009842:Oligopeptides; D034741:RNA, Small Interfering; D012910:Snake Venoms; C112567:etaracizumab; C422910:Cilengitide; C047981:arginyl-glycyl-aspartic acid