乳腺癌细胞MDA-MB-231侵袭转移中JAK抑制对ERK的作用及意义

目的:研究JAK激酶抑制剂AG490对乳腺癌细胞MDA-MB-231细胞外信号调节蛋白激酶(ERK)磷酸化的影响,探讨JAK激酶对ERK信号转导通路的作用以及在乳腺癌细胞侵袭转移中的调控意义.方法:以JAK激酶抑制剂AG490处理乳腺癌细胞MDA-MB-231,MTT法检测AG490对细胞的生长抑制作用;MTT法检测AG490处理后细胞对人工基底膜Matrigel的黏附能力变化;Transwell小室进行人工重组基底膜侵袭和迁移实验,检测AG490处理后细胞侵袭、迁移能力变化;Western印迹法检测AG490处理后细胞中磷酸化ERK(P-ERK)、基质金属蛋白酶9(MMP-9)蛋白水平变化.结果:应用JAK酶抑制剂AG490后MDA-MB-231细胞生长受到抑制,作用呈时效-量效依赖关系;MDA-MB-231细胞黏附、侵袭、迁移能力降低,同时细胞中P-ERK、MMP-9蛋白减少.结论:JAK激酶可以通过改变ERK的磷酸化水平影响ERK信号转导通路的活化.JAK激酶抑制对ERK信号转导通路的激活有阻断作用,可以抑制MMP-9的表达及乳腺癌细胞的侵袭转移.

Effect of Janus kinase inhibition on extracellular signal-regulated protein kinase during invasion and metastasis of human breast cancer cell MDA-MB-231

Objective:To explore the influence of Janus kinase inhibitor AG490 on phosphorylation of extracellular signal-regulated protein kinase (ERK) in the human breast cancer cell line MDA-MB-231,so as to discuss the effect of JAK on ERK signal transduction pathway and on invasion/metastasis of breast cancer cells. Methods: MDA-MB-231 cells were treated with Janus kinase inhibitor AG490; MTT assay was used to examine the proliferation of MDA-MB-231 cells and the adhesion of MDA-MB-231 cells to artificial basement membrane matrigel after AG490 treatment. Invasion and metastasis of MDA-MB-231 cells were evaluated with transwell chamber after treated with AG490.The expression of P-ERK and MMP-9 protein was determined by Western blotting assay. Results: AG490 inhibited the proliferation of MDA-MB-231 cells in a time- and dose-dependent manner; AG490 also depressed the adhesion, invasion and metastasis of MDA-MB-231 cells. Meanwhile, the expression of P-ERK and MMP-9 protein was decreased after treatment with AG490. Conclusion: Our study indicates that JAK kinase can affect the activity of ERK signal transduction pathway through the phosphorylation of ERK. The inhibitory effects of JAK kinase on MMP-9 expression and invasion of breast cancer cells are associated with the blocking of the ERK signaling pathway.