目的研究BRCA1是否可以调节黄体酮刺激乳腺癌细胞增殖和迁移。方法乳腺癌细胞MCF-7和T-47D转染质粒过表达BRCA1或转染相应空质粒作对照,并以黄体酮刺激乳腺癌细胞,观察过表达BRCA1对黄体酮刺激乳腺癌细胞增殖和迁移的影响;MCF-7细胞转染siRNA敲低BRCA1或转染杂乱siRNA作为对照,并加黄体酮刺激乳腺癌细胞,观察敲低BRCA1对黄体酮刺激乳腺癌细胞增殖和迁移的影响;用MTT实验结果计算细胞增殖率,用“划痕愈合实验”结果计算细胞迁移率。结果黄体酮刺激并转染空质粒对照组或过表达BRCA1组:细胞增殖率,MCF-7细胞分别是(114.4±6.0)%和(82.1±3.2)%,T47-D细胞分别是(111.3±4.3)%和(84.2±3.5)%,两组间细胞增殖率差异均有统计学意义(P〈0.05);细胞迁移率,MCF-7细胞分别是55.9%和15.8%,T-47D分别是44.83%和10.43%。加黄体酮刺激并转染杂乱siRNA或BRCAlsiRNAMCF-7:细胞增殖率分别是(114.4±3.05)%和(125.3±4.0)%,两组间差异有统计学意义(P〈0.05);细胞迁移率分别是39.2%和69.08%。黄体酮受体拮抗剂RU486可以拮抗敲低BRCA1增强黄体酮促进乳腺癌细胞增殖和迁移。结论散炭性乳腺癌可能因其BRCA1低表达而使黄体酮对乳腺癌细胞的增殖和迁移作用增强。
Objective To study the effect of BRCA1 in regulating the proliferation and migration of breast cancer ceils stimulated by progesterone. Methods Breast cancer MCF-7 and T-47D cell were transfected with a vector containing the coding sequence of BRCA1 (pFlag-CMV2-BRCA1 wt) to induce BRCA1 overexpression or with the empty vector (control). The cells were then stimulated with progesterone, and the cell proliferation and migration were observed using MTT assay and wound healing assay, respectively. The proliferation and migration of MCF-7 cells were also observed following transfection with a small interfering RNA (siRNA) for BRCA1 knockdown or with a scrambled siRNA prior to progesterone stimulation. Results Transfection with the empty vector and with pFlag-CMV2-BRCA1 wt prior to progesterone stimulation caused significantly different proliferation rates in MCF-7 cells [(114.4±6.0)% vs (82.1±3.2)%, P〈0.05] and in T-47D cells [(111.3±4.3)% vs (84.2±3.5)%, P〈0.05], resulting also in significantly different cell migration rates (55.9% vs 15.8% in MCF-7 cells and 44.83% vs 10.43% in T-47D cells). Compared to the scrambled siRNA, BRCA1 siRNA transfection prior to progesterone stimulation significantly increased the proliferation rates [(114.4±3.05)% vs (125.3±4.0)%, P〈0.05] and migration rate (39.2% vs 69.08%) of MCF-7 cells. The progesterone antagonist RU468 could antagonize the effects of BRCA1 knockdown in enhancing progesterone-stimulated MCF-7 cell proliferation and migration. Conclusions A decreased BRCA1 expression can enhance progesterone-stimulated tumor cell proliferation and migration in sporadic breast cancer.