腺病毒介导的野生型p53基因逆转乳腺癌耐药细胞株MCF-7/A耐药性的研究

目的 探讨野生型p53基因对乳腺癌耐药细胞株MCF-7/A耐药性的逆转作用及其机制.方法 选用含野生型p53基因的重组腺病毒载体,转染乳腺癌耐药细胞株MCF-7/A,绘制细胞生长曲线,利用流式细胞计数仪检测细胞周期分布及凋亡分析、TUNEL法检测细胞凋亡的发生,并采用逆转录-聚合酶链反应(RT-PCR)和Western blot印迹转移检测p53基因的表达情况.结果 野生型p53基因转染MCF-7/A后的24、48 h均检测到p53基因的表达,并显著抑制MCF-7/A细胞的增殖;细胞周期发生改变,转染后的MCF-7/A的G0%G1期DNA百分含量(76.22%)明显高于对照组(43.64%,P<0.05),凋亡率(10.76%)与对照组(1.48%)之间差异有统计学意义(P<0.05).结论 重组腺病毒介导的野生型p53基因对乳腺癌耐药细胞株MCF-7/A的耐药性有明显的逆转作用,其机制可能是引起明显的G1期阻滞并诱导细胞凋亡.

Reverse effect of adenovirus-mediated Wt-p53 on drug resistance of breast cancer cell line MCF-7/A

Objective To explore the reverse effect of Wt-p53 gene on drug resistance of breast cancer cell line MCF-7/A and its possible mechanism.Methods Wt-p53 gene was tranfected into MCF-7/A cells through rebuilding adenovirus.The cell growth curve was drawn, and the cycle distribution and apoptosis were checked by FCM.The apoptosis of MCF-7/A cells was examined by TUNEL.The expression of Wt-p53 mRNA and protein in MCF-7/A cells was detected by PT-PCR and Western blot respec-tively.Results In the transfection group of MCF-7/A cells, there was obvious proliferation, and the expression of p53 mRNA and protein was detected 24 and 48 h later.Aneuploid peak before G, stage indicated DNA destruction and cell apoptosis.The DNA content in transfection group in G0-G1 stage (76.22%) was significantly higher than control group (43.64%) (P < 0.05).The TUNEL verified that there was an apparent apoptosis signal in which the apoptosis rate of transfected MCF-7/A was 10.76% ,while that was 1.48% in control group (P < 0.05).Conclusion Recombinant adenovirus-mediated Wt-p53 has an apparently reverse effect on drug resistance of breast cancer MCF-7/A cells by inducing cell apoptosis and apparent G1 stage arrest.