ATR抑制剂VE-822对人乳腺癌细胞MCF-7的作用

Effects of ATR Inhibitor VE -822 on Human Breast Cancer MCF -7 Cells

目的检测ATR抑制剂VE-822对人乳腺癌细胞MCF-7的细胞增殖、周期及凋亡的影响,初步探讨其机制.方法采用对数生长期的人乳腺癌细胞MCF-7,给予不同浓度梯度ATR抑制剂VE-822干预24h、48h、72h,DMSO为对照组.CCK-8法检测各组MCF-7细胞增殖抑制情况,流式细胞术(Flowcytometry,FCM)检测其对细胞周期及凋亡的影响,并采用western blot检测p-ATR、p-chk1、BRCA1、rad51、γ-H2AX蛋白的表达.结果 VE-822处理组较DMSO对照组的MCF-7细胞增殖抑制率随药物浓度的增加而呈现剂量依赖效应,差异有统计学意义(P<0.05).实验组中MCF-7细胞发生G1/S期阻滞,并伴有细胞凋亡增加,差异有统计学意义(P<0.05).实验组中p-ATR、p-chk1、BRCA1、rad51蛋白含量较对照组降低,差异有统计学意义(P<0.05).实验组中γ-H2AX蛋白含量较对照组升高,差异有统计学意义(P<0.05).结论 ATR抑制剂VE-822可明显抑制体外人乳腺癌细胞MCF-7增殖、诱导细胞周期阻滞和细胞凋亡,其机制可能与抑制同源重组修复(homologous recombinational repair,HRR)和非同源重组修复(non-homologous end joining,NHEJ)有关.

Objective To investigate effects of ATR inhibitor VE-822 on proliferation, cycle and apoptosis of human breast cancer MCF-7 cells and explore its mechanism. Methods MCF-7 cells were treated with different concentrations of VE-822 for 24 h ,48 h , and 72 h. DMSO-treated MCF-7 cells were used as control group. Then the proliferation of cells were measured with CCK-8 method. The cell cycle and apoptosis of MCF-7 cells were measured by flow cytometry ( FCM). The expression of protein levels of p-ATR, p-chkl , BRCA1 , rad51 and γ- H2AX were detected by western blotting. Results The proliferation rates of VE-822 treated MCF-7 cells significantly decreased compared with DMSO control groups ( P < 0. 05 ). VE-822 treated MCF-7 cells were arrested at Gl/S phase and were associated with increased apoptosis compared to DMSO-controlled group( P < 0. 05 ). The protein expression of p-ATR,p-chkl , BRCA1 and ra(151 obviously reduced in VE-822-treated group compared with control group( P < 0. 05 ). The expression level of 7-H2AX significantly increased compared to control group( P < 0. 05). Conclusion ATR inhibitor VE-822 can significantly inhibite proliferation of MCF-7 cells and induce Gl/ S cell cycle arrest and apoptosis in vitro. The mechanism may be related to inhibiting homologous recombinational repair and non-homologous end joining.