雌激素通过ERK-FAK信号通路调节MCF-7乳腺癌细胞失巢凋亡  

Estrogen regulates anoikis through extracellular signal-regulated kinase( ERK)-focal adhesion kinase( FAK) signaling in MCF-7 breast cancer cells

作　　者：何艳[1] 王丹丹[1] 陈华妹[1] 李勇杰[1] 薛启祥 王旭东[1] 

机构地区：[1]贵阳医学院生理学教研室,贵州贵阳550004 [2]贵阳医学院病理生理学教研室,贵州贵阳550004

出　　处：《基础医学与临床》2015年第9期1194-1198,共5页Basic and Clinical Medicine

基　　金：国家自然科学基金(31360252;30860093)

摘　　要：目的探讨雌激素(E2)对MCF-7乳腺癌细胞抗失巢凋亡能力的影响及细胞外信号调节激酶(ERK)-局部黏着斑激酶(FAK)通路在其中的作用,以加深对E2促癌作用信号机制的认识。方法用MCF-7乳腺癌细胞,聚甲基丙烯酸羟乙基酯(poly-Hema)涂层培养细胞诱导失巢凋亡,E2刺激及MEK和FAK抑制剂预处理细胞。用蛋白印迹法检测ERK和FAK磷酸化,台盼蓝染色细胞计数法检测细胞存活力,Hoechst荧光染色法验证细胞凋亡。结果用Poly-Hema悬浮培养可显著降低细胞存活力(P<0.01),E2处理则可明显增强悬浮培养细胞的存活力(P<0.05),同时减少细胞凋亡;E2可引起ERK和FAK磷酸化,MEK抑制剂则可显著抑制E2诱导的ERK和FAK磷酸化,并使E2处理的悬浮培养细胞存活率下降57.48%(P<0.01);FAK抑制剂能明显抑制FAK和ERK的磷酸化,同时使E2处理的悬浮培养细胞存活率下降53.59%(P<0.01)。结论 E2可明显提高MCF-7乳腺癌细胞对抗失巢凋亡的能力,该细胞保护效应可能与E2激活胞内ERK-FAK信号活动有关。Objective To investigate the effects of estrogen （E2）on the resistance to anoikis and a possible role of extracellular signal-regulated kinse （ERK）-focal adhesion kinse （FAK） signaling in the effect of estrogen to under- stand its underlying mechanism. Methods Poly-Hema-coated culture of human breast cancer cell line MCF-7 was used to induce anoikis. Cells were treated with E2 and/or pretreated with MEK or FAK inhibitors. Western blot was used to assess the phosphorylation of ERK and FAK, trypan blue staining and cell counting were employed to evaluate cell viability, and Hoechst staining was used to check apoptosis. Results Suspension culture greatly re- duced cell survival （P 〈0.01 ） , and exposure of MCF-7 cells to E2 （10 nmol/L） led to a significantly increased resistance to anoikis and survival （P 〈 0.05 ） as compared to DMSO. Meanwhile, E2 induced increased phospho- rylation of both ERK and FAK. Pharmacological inhibition of MEK with U0126 （10 μmol/L） reduced E2-in- creased cell survival by 57.48% （P 〈0. 01 ） and E2-decreased anoikis; Treatment with FAK inhibitor（ 10 μmol/L） attenuated E2-enhanced cell survival by 53.59% （ P 〈 0.01 ） and E2-reduced apoptosis. Conclusions E2 con- tributes to the enhanced cell viability and increased resistance to anoikis in MCF-7 breast cancer cells, and ERK- FAK signaling may be involved in the E2-stimulated survival during suspension culture of MCF-7 cells.

关 键 词：雌激素 细胞外信号调节激酶 局部黏着斑激酶 失巢凋亡 乳腺癌细胞 

分 类 号：R737.9[医药卫生—肿瘤]