内皮抑素的作用机制以及在肿瘤治疗中的研究现状

内皮抑素是胶原ⅩⅧ的20kD水解片断，它是血管生成最有效的天然抑制剂之一，特异性抑制内皮细胞的增殖，通过抑制细胞周期素D1而诱导凋亡。在内皮细胞表面，内皮抑素与整合素α5β1结合从而激活Src激酶，此外也下调RhoAGTP酶的活性，抑制Ras和Raf激酶家族介导的信号传导。所有的事件均导致激动蛋白细胞骨架的解体，细胞-基质相互作用的紊乱，内皮细胞迁移活性的下降等，抑制血管生成。本文概述内皮抑素的生物学活性及作用机制。

The action mechanisms of endostatin and advances in anti-tumor treatments

Endostatin, a 20-kD proteolytic fragment of type ⅩⅧ collagen, is one of the most active natural inhibitors of angiogenesis. It specifically inhibits the proliferation of endothelial cells, and induces their apoptosis through inhibition of cyclin D1. On the surface of endothelial cells, endostatin binds with the integrin α5β1 that activates the Src-kinase pathway. The binding of endostatin with integrins also down-regulates the activity of RhoA GTPase and inhibits signaling pathways mediated by small kinases of the Ras and Raf families. All these events promote disassembly of the actin cytoskeleton, disorders in cell-matrix interactions, and decrease in endotheliocyte mobility, i.e., promote the suppression of angiogenesis. This review summarizes results of numerous studies concerning the biological activity and action mechanism of endostatin.