肿瘤细胞向血管外游走过程中内皮细胞调控机制的研究

目的：阐明肿瘤细胞向血管外游走过程中内皮细胞肌球蛋白轻链激酶(MLCK)及Rho／Rho激酶的调控作用。方法：利用肿瘤细胞向血管外游走的体外模型，观察肿瘤细胞的血管外游走状况，并测定肿瘤细胞游走过程中血管内皮单细胞层的电阻变化；通过Western blot评价肿瘤游走过程中内皮细胞肌球蛋白轻链(MLC)的磷酸化水平。结果：肿瘤细胞可以穿过血管内皮细胞游走至血管外；并且肿瘤细胞向血管外游走过程中跨血管内皮细胞层的电阻下降、内皮细胞MLC的磷酸化水平升高；而内皮细胞肌球蛋白轻链激酶抑制剂(ML-7)及Rho抑制剂(C3转移酶)、Rho激酶抑制剂(Y-27632)能够抑制上述变化。结论：内皮细胞MLCK及Rho／Rho激酶可以通过控制MLC的磷酸化水平来引起内皮细胞骨架蛋白的改变，从而调控肿瘤细胞穿过内皮细胞间缝隙向血管外游走。

The effect of endothelial cell in extravascular migration of tumor cell

Objective:To evaluate the effect of endothelial MLCK and Rho/Rho kinase in extravascular m igration of tumor cell.Methods:Used an in vitro model of tumor cell transmigration across a monolayer of HUV EC cultured on collagen gel to observe extravascular migration of tumor cells,ca lculated the electrical resistance of HUVEC monolayer and endothelial MLC phosph orylation in extravascular migration of tumor cells.Results:Tumor cells migrated through endothelial cells into collagen gel,the electrical resistance of a HUVEC monolayer reduced and endothelial MLC phosphorylation enha nced in extravascular migration of tumor cells.Endothelial MLCK inhibitor(ML-7) ,Rho inhibitor(C3 transferase) and Rho kinase inhibitor(Y-27632) inhibited extr avascular migration of tumor cells and inhibited reduction of electrical resista nce of a HUVEC monolayer and enhancement of endothelial MLC phosphorylation in e xtravascular migration of tumor cells.Conclusion:Endothelian MLCK and Rho/Rho kinase regulates tumor cell transendothelial migrat ion through MLC phosphorylation and modification of endothelial cytoskeleton.