Breast Center of Military General Hospital of Beijing PLA, China.
Anticancer Drugs. 2011 Jul;22(6):556-62. doi: 10.1097/CAD.0b013e328345b4e7.
The aim of this study was to determine whether adenovirus-mediated p53 gene (Ad-p53) transfection can enhance adriamycin cytotoxicity and reverse adriamycin resistance in human breast cancer cells and explore its effect on the expression of MDR1 gene and permeability-glycoprotein (P-gp). Human breast cancer cell lines, MCF-7 and MCF-7/ADR, were used in in-vitro studies. After infection with Ad-p53, the cytotoxicity of adriamycin was evaluated using the Cell Counting Kit-8 assay. The expression of MDR1 mRNA was detected by quantitative real-time PCR. The expression of P-gp was analyzed using western blotting. In in-vivo studies, MCF-7/ADR tumor cells were inoculated subcutaneously in athymic nude mice. After 14 days of inoculation, tumor size was measured. Apoptosis and expression of P-gp in the tumor tissue were analyzed by fluorescence activated cell sorting and western blotting. After transfection with a multiplicity of infection of 50 for Ad-p53, chemosensitivity of MCF-7/ADR cells increased by 18.1 times (P=0.001), and 50% inhibitory concentration (IC50) of adriamycin decreased from 4.54 ± 0.91 to 0.26 ± 0.11 mg/l. Real-time PCR showed that MDR1 mRNA decreased from 1.32 to 0.85 (P=0.001). Western blotting analysis showed that P-gp also decreased. In in-vivo studies, Ad-p53 combined with adriamycin dramatically inhibited the growth of subcutaneous xenograft of MCF-7/ADR. The fluorescence activated cell sorting assay showed that there were more apoptotic cells in tumor tissues treated with Ad-p53 and adriamycin. The expression of P-gp was significantly decreased in tumor tissues. This study suggests that Ad-p53 can reverse MCF-7/MDR cell resistance to adriamycin. The reversal effect was associated with inhibition of P-gp expression and induction of apoptosis.
本研究旨在探讨腺病毒介导的 p53 基因（Ad-p53）转染能否增强阿霉素在人乳腺癌细胞中的细胞毒性，逆转阿霉素耐药性，并探讨其对多药耐药基因（MDR1）和 P-糖蛋白（P-gp）表达的影响。采用体外研究人乳腺癌细胞系 MCF-7 和 MCF-7/ADR。用 Ad-p53 感染后，用细胞计数试剂盒-8 法评估阿霉素的细胞毒性。用实时定量 PCR 检测 MDR1 mRNA 的表达。用 Western blot 分析 P-gp 的表达。在体内研究中，将 MCF-7/ADR 肿瘤细胞皮下接种于裸鼠。接种 14 天后，测量肿瘤大小。用荧光激活细胞分选和 Western blot 分析肿瘤组织中的细胞凋亡和 P-gp 表达。用 Ad-p53 感染复数为 50 转染后，MCF-7/ADR 细胞的化疗敏感性增加了 18.1 倍（P=0.001），阿霉素的 50%抑制浓度（IC50）从 4.54±0.91 降至 0.26±0.11mg/L。实时 PCR 显示 MDR1 mRNA 从 1.32 降至 0.85（P=0.001）。Western blot 分析显示 P-gp 也减少了。在体内研究中，Ad-p53 联合阿霉素显著抑制 MCF-7/ADR 皮下移植瘤的生长。荧光激活细胞分选试验显示，用 Ad-p53 和阿霉素处理的肿瘤组织中凋亡细胞增多。肿瘤组织中 P-gp 的表达明显降低。本研究表明，Ad-p53 可逆转 MCF-7/MDR 细胞对阿霉素的耐药性。逆转作用与抑制 P-gp 表达和诱导细胞凋亡有关。
