Bak基因转染对乳腺癌MCF-7细胞增殖及对紫杉醇敏感性的影响

目的 探讨Bak基因转染对乳腺癌MCF-7细胞增殖及对紫杉醇敏感性的影响。 方法 采用Western blotting法和Real-time PCR检测乳腺癌MCF-7细胞转染前后Bak蛋白表达。通过细胞计数试剂盒8（CCK-8）和流式细胞术检测Bak基因转染后，及紫杉醇作用24 h、48 h和72 h后对MCF-7细胞增殖和细胞周期的影响。 结果 Western blotting和 Real-time PCR检测结果显示，转染质粒后，Bak蛋白表达量显著升高，MCF-7 Bak组mRNA表达量为2.15±0.07，明显高于MCF-7 NC组1.03±0.04（t=13.412，P<0.05）。转染48 h、72 h和96 h后，MCF-7 Bak细胞增殖速率为（0.31±0.03）%、（0.37±0.03）%、（0.47±0.04）%，低于MCF-7 NC组的（0.40±0.03）%、0.48±0.04）%、（0.61±0.06）%，差异有统计学意义（t ₄₈=2.145、t ₇₂=3.164、t ₉₆=5.487，P<0.05）。MCF-7 Bak组G2期细胞数是（26.84±2.69）%，显著高于MCF-7 NC组（16.02±1.61）%（t=12.887，P<0.05）。紫杉醇作用24 h、48 h和72 h后，MCF-7 Bak组细胞增殖抑制率为（35.98±4.00）%、（54.66±5.50）%、（80.11±8.00）%，高于MCF-7 NC组的（24.12±2.40）%、（40.12±4.00）%、（61.09±6.09）%，差异有统计学意义（t ₂₄=8.456、t ₄₈=10.547、t ₇₂=13.442，P<0.05）。紫杉醇作用24 h后，MCF-7 Bak组G0/G1期细胞数（73.01±7.02）%高于MCF-7 NC组（63.84±6.68）%（P<0.05）。 结论 上调Bak基因表达可抑制乳腺癌MCF-7细胞增殖，上调G0/G1期比例，增强紫杉醇的敏感性。

Effect of Bak gene overexpression on proliferation of breast cancer MCF-7 cells and sensitivity to paclitaxel

Objective To investigate the effect of Bak gene overexpression on proliferation of breast cancer MCF-7 cells and sensitivity to paclitaxel. Methods Western blotting and Real-time PCR were used to detect the expression of Bak protein in breast cancer MCF-7 cells before and after transfection. The effects of Bak gene overexpression and paclitaxel treatment for 24 hours, 48 hours and 72 hours on MCF-7 cell proliferation and cell cycle were detected by cell counting kit-8(CCK-8) and flow cytometry. Results The results of Western blotting and Real-time PCR showed that the expression of Bak protein increased significantly after transfection.The results of Western blotting and Real-time PCR showed that the expression of Bak protein increased significantly after transfection, and the mRNA expression of MCF-7-Bak group was 2.15±0.07, which was significantly higher than that of MCF-7-NC group,which was 1.03±0.04(t=13.412, P<0.05).After 48 hours, 72 hours and 96 hours of transfection, the proliferation rates of MCF-7-Bak cells were (0.31±0.03)%, (0.37±0.03)%, (0.47±0.04)%, respectively, which were lower than that of MCF-7 NC group(0.40±0.03)%, (0.48±0.04)%, (0.61±0.06)%, and the difference was statistically significant (t ₄₈=2.145, t ₇₂=3.164, t ₉₆=5.487, P<0.05). The number of G2 phase cells in MCF-7 Bak group were (26.84±2.69)% significantly higher than that in MCF-7 NC group (16.02±1.61)% (t=12.887, P<0.05). After 24 hours, 48 hours, and 72 hours of paclitaxel treatment, the cell inhibition rate of MCF-7-Bak group was (35.98±4.00)%, (54.66±5.50)%, (80.11±8.00)%, respectively, which were higher than that of MCF-7 NC group (24.12±2.40)%, (40.12±4.00)%,(61.09±6.09)%. And the difference was statistically significant (t ₂₄=8.456, t ₄₈=10.547, t ₇₂=13.442, P<0.05). After 24 hours of paclitaxel treatment, the number of G2 phase cells in MCF-7 Bak group was (73.01±7.02)% higher than that in MCF-7 NC group (63.84±6.68) %(t=9.736, P<0.05). Conclusion Up-regulate of Bak gene expression can inhibit the proliferation of breast cancer MCF-7 cells, up-regulating the proportion of G0/G1 phase, and enhance the sensitivity of paclitaxel.