阻断Hh信号通路活性增敏Let-7抑制三阴性乳腺癌细胞增殖的作用及机制研究

Inhibiting Hedgehog signaling activity sensitized triple negative breast cancer cells to Let-7 suppression of proliferation

目的:目的:探讨阻断Hh信号通路活性增敏Let-7抑制三阴性乳腺癌细胞增殖的作用及机制研究。方法:应用qRT-PCR和Western Blot、免疫组化(IHC)和免疫荧光(IF)在内的多种生物学实验方法,从临床标本及体外细胞实验的角度探究Let-7增敏TNBC的作用及可能与Hh信号通路的相关性。结果:阻断Hh信号通路降低了MDA-MB-231及BT-20细胞的增殖能力,并且增强了Let-7对三阴乳腺癌细胞系增殖能力的抑制作用。Let-7对MDA-MB-231及BT-20细胞内Cyclin D1水平的影响微弱,但是通过Hh通路的抑制剂环巴胺则有效的增强了Let-7对Cyclin D1的抑制作用,进一步在肿瘤干细胞样细胞亚群中,Hh通路抑制剂降低了MDA-MB-231及BT-20细胞系中ALDH1阳性干细胞亚群的比例,增强了Let-7对乳腺癌干细胞亚群自我更新能力的抑制作用。结论:Hh通路抑制剂通过对Cyclin D1的共抑制可以增强Let-7抑制三阴性乳腺癌细胞的增殖。

Objective：To investigate inhibiting Hedgehog signaling activity sensitized triple negative breast cancer cells to Let -7 suppression of proliferation. Methods：In this study, muhiple molecular and biology technologies were used, such as qRT - PCR, Western Blot, immunohistochemistry, immunofluorescence, ect, to study the possible roles and implicated mechanisms in vitro and in clinical samples. Results：We found the inhibition of Hedgehog inhibited MDA- MB- 231 cells and BT- 20 cells＂ proliferation, and help to sensitize MDA- MB -231 and BT- 20 cells to Let- 7 induced proliferation inhibition. Let -7 showed no significant effects on the Cyclin D1 level, but its effects were greatly strengthened by Hedgehog pathway inhibitor of cyclopamine. We also found that cyclopamine inhibits the ratio of ALDH1 ＋ cells of both MDA - MB -231 and BT -20 cells, and strengthened the inhibitory effects of Let -7. Conclusion ：Hedgehog inhibitor could improve the effects of Let -7 miRNAs in repressing breasts cancer cells prolifera-