Okayama University Medical School Acta Medica Okayama 0386-300X 70 1 2016 The Function of ƒÀ2-glycoprotein I in Angiogenesis and Its in Vivo Distribution in Tumor Xenografts 13 24 EN Arum Tri Wahyuningsih Lianhua Shen Kazuko Kobayashi Takanori Sasaki Fumiaki Takenaka Takahisa Hanada Masaru Akehi Akiya Akahoshi Eiichi Ozeki Eiji Ando Eiji Matsuura Original Article 10.18926/AMO/53999 Intact ƒÀ2-glycoprotein I (iƒÀ2GPI) is a glycoprotein that regulates coagulation and fibrinolysis. Nicked ƒÀ2GPI (nƒÀ2GPI) possesses an angiogenic property at a relatively low concentration, and an antiangiogenic property at a high concentration. Here we investigated the functions of ƒÀi 2GPI and nƒÀ2GPI in vascular endothelial growth factor (VEGF)-A-induced endothelial cell proliferation and tube formation. We used noninvasive PET imaging to analyze the in vivo distribution of intravenously injected ƒÀ2GPI variants in tumor lesions in mice. iƒÀ2GPI was incubated with plasmin to obtain nƒÀ2GPI, and its N-terminal sequence was analyzed. nƒÀ2GPI had at least one other cleavage site upstream of the ƒÀ2GPIʼs domain V, whereas the former plasmin-cleavage site locates between K317 and T318. Both of intact and nicked ƒÀ2GPI significantly inhibited the VEGF-A-induced cell proliferation and the tube formation of human umbilical vein endothelial cells (HUVECs). PET imaging visualized considerably distributed intensities of all tested ƒÀ2GPI variants in tumor lesions of pancreatic tumor cell-xenografts. These results indicate that ƒÀ2GPI may be physiologically and pathophysiologically important in the regulation of not only coagulation and fibrinolysis, but also angiogenesis. No potential conflict of interest relevant to this article was reported.