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

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

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(t48=2.145、t72=3.164、t96=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(t24=8.456、t48=10.547、t72=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。

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( t48= 2. 145,t72= 3. 164,t96= 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-7NC 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-7NC group( 24. 12 ± 2. 40) %,( 40. 12 ± 4. 00) %,( 61. 09 ± 6. 09) %.And the difference was statistically significant( t24= 8. 456,t48= 10. 547,t72= 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-7NC 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.