Dual Function of RGD-Modified VEGI-192 for Breast Cancer Treatment

作者:Wu, Jueheng; Jiang, Yi; Yang, Wan; He, Zhenjian; Meng, Shiyu; Zhang, Qianhui; Lin, Min; Zhang, Henan; Li, Weifeng; Yang, Yaochao; Jia, Yiqun; Qian, Liang; Lu, Dihan; Cai, Wenjia; Luo, Guotian; Wang, Yesong; Zhu, Xun*; Li, Mengfeng
来源:Bioconjugate Chemistry, 2012, 23(4): 796-804.
DOI:10.1021/bc2006576

摘要

Identification of endogenous angiogenesis inhibitors has led to development of an increasingly attractive strategy for cancer therapy and other angiogenesis-driven diseases. Vascular endothelial growth inhibitor (VEGI), a potent and relatively nontoxic endogenous angiogenesis inhibitor, has been intensively studied, and this work shed new light on developing promising anti-angiogenic strategies. It is well-documented that the RGD (Arg-Gly-Asp) motif exhibits high binding affinity to integrin alpha(v)beta(3), which is abundantly expressed in cancer cells and specifically associated with angiogenesis on tumors. Here, we designed a fusion protein containing the special RGD-4C motif sequence and VEGI-192, aimed at offering more effective multiple targeting to tumor cells and tumor vasculature, and higher anti-angiogenic and antitumor efficacy. Functional tests demonstrated that the purified recombinant human RGD-VEGI-192 protein (rhRGD-VEGI-192) potently inhibited endothelial growth in vitro and suppressed neovascularization in chicken chorioallantoic membrane in vivo, to a higher degree as compared with rhVEGI-192 protein. More importantly, rhRGD-VEGI-192, but not rhVEGI-192 protein, could potentially target MDA-MB-435 breast tumor cells, significantly inhibiting growth of MDA-MB-435 cells in vitro, triggered apoptosis in MDA-MB-435 cells by activation of caspase-8 as well as caspase-3, which was mediated by activating the JNK signaling associated with upregulation of pro-apoptotic protein Puma, and consequently led to the observed significant antitumor effect in vivo against a human breast cancer xenograft. Our study indicated that the RGD-VEGI-192 fusion protein might represent a novel anti-angiogenic and antitumor strategy.