腺病毒介导p53基因逆转乳腺癌耐药的实验研究

Experimental study of adenovirus-mediated p53 gene on the reversal of multidrug resistance in breast cancer

目的探讨腺病毒介导 p53基因(Ad-p53)对人乳腺癌阿霉素(ADM)耐药细胞株MCF-7/ADM 的耐药性及多药耐药基因1(MDR1)的影响。方法以 Ad-p53转染 MCF-7/ADM 细胞株,流式细胞术检测 p53蛋白变化;锥虫蓝活细胞拒染法观察细胞生长情况;MTT 法观察 MCF-7/ADM 细胞对阿霉素耐药性的变化,实时荧光 RT-PCR 法检测 MDR1 mRNA 变化。结果流式细胞术观察到 MCF-7/ADM 细胞经 MOI_(50)的 Ad-p53作用48 h 后,p53蛋白表达率由10.24%升高到36.20%;细胞抑制率为7.4%(P=0.003);逆转 MCF-7/ADM 对 ADM 的耐药倍数11.6倍(P=0.001);实时荧光 RT-PCR 检测结果显示 MDR1 mRNA 相对表达量由1.25±0.01下降至0.91±0.01(P=0.011)。结论腺病毒介导 p53基因能抑制 MCF-7/ADM 细胞 MDR1基因的表达,并能部分逆转MCF-7/ADM 的耐药性,增加阿霉素化疗敏感性。

Objective To explore the effects of adenovirus-mediated wild-type p53 gene （Ad-p53） on the reversal of multidrug resistance （MDR） and multidrug resistance gene-1 （ MDR1 ） in adriamycin （ADM） resistant human breast cancer cell. Methods Ad-p53 was transfected into the human breast cancer cells of the line MCF-7/ADM. p53 protein expression was detected by flow cytometry （FCM）. The cell proliferation was assessed by trypan blue dye exclusion. The effects of Ad-p53 on ADM mediated drug resistance were observed by MTT assay. The expression levels of MDR1 mRNA were detected with real-time RT-PCR. Results The expression rate of p53 protein of the MCF-7/ADM cell was increased from 10.24% to 36.20% after transfected by MOIso Ad-p53 for 48 hours. The growth inhibition rate was 7.4 % （ P = 0. 003）. The chemosensifivity of MCF-7/ADM to ADM increased by 11.6 times（P =0.001）.The result of realtime RT-PCR reveales that MDR1 mRNA was decreased from 1.25 ±0.01 to 0.91 ±0.01 （P =0.011） after the MCF-7/ADM cells were transfected by Ad-p53. Conclusion Ad-p53 can inhibit the expression of MDR1 gene and partially reverse the MDR of MCF-7/ADM cells, thusenhancing the chemositivity of human breast cancer cells to ADM.