雌、孕激素联合给药逆转miR-145对三阴性乳腺癌的抑癌作用

Reversal of miR-145 in triple-negative breast cancer by estrogen and progesterone combined administration

目的探讨雌、孕激素在三阴性乳腺癌形成中的作用及相关分子机制。方法构建MDA-MB-231/miR-145及MDA-MB-231/miR-SCR(对照组)稳定细胞株,分5组培养细胞,分别为miR-SCR组、miR-145组、miR-145+E2组、miR-145+P4组、miR-145+E2+P4组,分别分组给药。利用CCK-8试剂盒检测细胞增殖能力,Western blot检测miR-145靶基因胰岛素样生长因子受体-1(IGF-1R)、N-RAS的蛋白表达水平,荧光定量PCR(qRT-PCR)检测IGF-1R、N-RAS下游信号分子血管内皮生长因子(VEGF)的表达水平及转染后miR-145的表达。结果 CCK-8试剂盒检测结果显示,雌、孕激素联合给药可逆转miR-145对三阴性乳腺癌细胞增殖的抑制作用(P<0.05)。Western blot法检测结果显示,雌、孕激素联合给药使miR-145靶基因IGF-1R、N-RAS的蛋白表达水平上升。qRT-PCR检测结果显示,与对照组比较,转染后miR-145的表达水平上升(P<0.05);雌、孕激素联合给药使VEGF的表达水平明显上升(P<0.01)。结论雌、孕激素联合给药可促进三阴性乳腺癌VEGF的表达和细胞增殖,从而逆转miR-145在三阴性乳腺癌中的抑癌作用。

Objective To investigate the role of estrogen and progesterone in the tumorigenesis of triple-negative breast cancer and its molecular mechanism. Methods To construct of MDA-MB-231/miR-145 and MDA-MB-231/ miR-SCR（ scramble control） stable cell lines. The cells were cultured in five groups that were respectively miR- SCR group, miR-145 group, miR-145 ＋ E2 group, miR-145 ＋ P4 group, miR-145 ＋ E2 ＋ P4 group, grouped administradion. Cell proliferation was detected by CCK-8 kit, the expression level of miR-145 target gene insulin-like growth factor receptor-1 （IGF-1R） , N-RAS was detected by Western blot, expression of IGF-1R, N-RAS downstream signaling molecule vascular endothelial growth factor（VEGF） and expression of miR-145 after transfection was detected by real-time quantitative PCR（qRT-PCR）. Results The results of CCK-8 assay showed that estrogen and progesterone combined administration could reverse the inhibitory effect of miR-145 on the proliferation of triple-negative breast cancer cells （P 〈 0.05 ）. The results of Western blot showed that estrogen and progesterone combined administration could increase the expression level of IGF-1R and N-RAS in the target gene of miR-145. The results of qRT-PCR showed that the expression level of miR-145 was significantly higher than that of control group （P 〈 0. 05 ） and the expression of VEGF was significantly increased by estrogen and progesterone combined administration （P 〈 0.01 ）. Conclusion Estrogen and progesterone combined administration can promote the expression of VEGF and cell proliferation, and then reverse the anti-tumor effect of miR-145 in the triple-negative breast cancer.