miR-206通过调节ERα水平影响乳腺癌细胞MCF-7对他莫昔芬敏感度的初步研究

Influences of miR-206 on Sensitivity of Estrogen Receptor-α Positive Breast Cancer Cells MCF-7 to Tamoxifen

目的探讨乳腺癌细胞株MCF-7中miR-206能否调节ERα表达水平并影响乳腺癌细胞对他莫昔芬的敏感度。方法将miR-206 mimic、miR-206 inhibitor及相应阴性对照(miR-206 mimic NC、miR-206 inhibitor NC)分别转染乳腺癌MCF-7细胞,RT-PCR法检测转染后各组乳腺癌细胞中miR-206和ERαm RNA的表达量,用5μg/ml他莫昔芬处理MCF-7细胞后,MTT法检测不同转染组细胞增殖情况。结果miR-206 mimic组中乳腺癌细胞miR-206表达升高,ERαm RNA表达降低;miR-206 inhibitor组中乳腺癌细胞miR-206表达降低,ERαm RNA表达升高。他莫昔芬作用24 h后,miR-206 mimic组与阴性对照组(miR-206 mimic NC)的乳腺癌细胞增殖抑制差异无统计学意义(t=-1.169,P=0.276);miR-206 inhibitor组的乳腺癌细胞增殖抑制明显强于阴性对照组(miR-206 inhibitor NC)(t=-3.054,P=0.016)。结论下调miR-206表达可以增加ERα阳性乳腺癌细胞对他莫昔芬的敏感度。

Objective To investigate the influences of miR-206 on estrogen receptor-α expression and the sensitivity of breast cancer cells MCF-7 to tamoxifen. Methods The levels of miR-206 and ERα m RNA of breast cancer cells MCF-7 were quantitated by RT-PCR; the change of expression of miR-206 and ERα m RNA were quantitated after MCF-7 cells were transfected by miR-206 mimic, inhibitor and corresponding negative controls for 24h; cell growth was measured by MTT after transfected MCF-7 cells were treated with 5ug/ml tamoxifen for 24 h. Results Compared with corresponding negative controls, miR-206 mimic decreased ERα m RNA expression while increased miR-206 expression in MCF-7 cells but had no notably effect on cell growth after tamoxifen treatment for 24h(t=-1.169, P=0.276); miR-206 inhibitor increased ERα m RNA expression while decreased miR-206 expression in MCF-7 cells and had notably effect on cell growth after tamoxifen treatment for 24h(t=-3.054, P=0.016). Conclusion Downregulating miR-206 expression could increase the sensitivity of ERα positive breast cancer cells MCF-7 to tamoxifen.