TY - JOUR
T1 - Direct targeting of αvβ3 integrin on tumor cells with a monoclonal antibody, Abegrin ™
AU - Mulgrew, Kathy
AU - Kinneer, Krista
AU - Yao, Xiao Tao
AU - Ward, Beth K.
AU - Damschroder, Melissa M.
AU - Walsh, Bill
AU - Mao, Su Yau
AU - Gao, Changshou
AU - Kiener, Peter A.
AU - Coats, Steve
AU - Kinch, Michael S.
AU - Tice, David A.
PY - 2006/12
Y1 - 2006/12
N2 - The humanized monoclonal antibody Abegrin™, currently in phase II trials for treatment of solid tumors, specifically recognizes the integrin αvβ3. Due to its high expression on mature osteoclasts, angiogenic endothelial cells, and tumor cells, integrin αvβ3 functions in several pathologic processes important to tumor growth and metastasis. Targeting of this integrin with Abegrin™ results in antitumor, antiangiogenic, and antiosteolytic activities. Here, we exploit the species specificity of Abegrin™, to evaluate the effects of direct targeting of tumor cells (independent of targeting of endothelia or asteoclasts). Flow cytometry analysis of human tumor cell lines shows high levels of αvβ3 on many solid tumors, including cancers of the prostate, skin, ovary, kidney, lung, and breast. We also show that tumor growth of αvβ 3-expressing tumor cells is inhibited by Abegrin™ in a dose-dependent manner. We present a novel finding that high-dose administration can actively impair the antitumor activity of Abegrin™. We also provide evidence that antibody-dependent cellular cytotoxicity contributes to in vitro and in vivo antitumor activity. Finally, it was observed that peak biological activity of Abegrin™ arises at serum levels that are consistent with those achieved in clinical trials. These results support a concept that Abegrin™ can be used to achieve selective targeting of the many tumor cells that express αvβ3 integrin. In combination with the well-established concept that α vβ3 plays a key role in cancer-associated angiogenesis and osteolytic activities, this triad of activity could provide new opportunities for therapeutic targeting of cancer.
AB - The humanized monoclonal antibody Abegrin™, currently in phase II trials for treatment of solid tumors, specifically recognizes the integrin αvβ3. Due to its high expression on mature osteoclasts, angiogenic endothelial cells, and tumor cells, integrin αvβ3 functions in several pathologic processes important to tumor growth and metastasis. Targeting of this integrin with Abegrin™ results in antitumor, antiangiogenic, and antiosteolytic activities. Here, we exploit the species specificity of Abegrin™, to evaluate the effects of direct targeting of tumor cells (independent of targeting of endothelia or asteoclasts). Flow cytometry analysis of human tumor cell lines shows high levels of αvβ3 on many solid tumors, including cancers of the prostate, skin, ovary, kidney, lung, and breast. We also show that tumor growth of αvβ 3-expressing tumor cells is inhibited by Abegrin™ in a dose-dependent manner. We present a novel finding that high-dose administration can actively impair the antitumor activity of Abegrin™. We also provide evidence that antibody-dependent cellular cytotoxicity contributes to in vitro and in vivo antitumor activity. Finally, it was observed that peak biological activity of Abegrin™ arises at serum levels that are consistent with those achieved in clinical trials. These results support a concept that Abegrin™ can be used to achieve selective targeting of the many tumor cells that express αvβ3 integrin. In combination with the well-established concept that α vβ3 plays a key role in cancer-associated angiogenesis and osteolytic activities, this triad of activity could provide new opportunities for therapeutic targeting of cancer.
UR - http://www.scopus.com/inward/record.url?scp=33846188062&partnerID=8YFLogxK
U2 - 10.1158/1535-7163.MCT-06-0356
DO - 10.1158/1535-7163.MCT-06-0356
M3 - Article
C2 - 17172415
AN - SCOPUS:33846188062
SN - 1535-7163
VL - 5
SP - 3122
EP - 3129
JO - Molecular Cancer Therapeutics
JF - Molecular Cancer Therapeutics
IS - 12
ER -