FANCF基因干预乳腺癌细胞耐药性的信号转导机制

项目名称： FANCF基因干预乳腺癌细胞耐药性的信号转导机制

项目编号： No.30873097

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 生物科学

项目作者： 魏敏杰

作者单位： 中国医科大学

项目金额： 31万元

中文摘要： 本研究通过RNAi抑制FANCF表达，观察FANCF沉默对乳腺癌细胞生物学特性的影响，并进一步分别以雌激素受体（ER）阴性的MCF-7和ER阳性的MDA-MB-435S乳腺癌细胞，及p53野生型MCF7和p53变异型T47D乳腺癌细胞，通过RNAi沉默FANCF，体外水平检测不同基因特性细胞对化疗药物丝裂霉素（MMC）、米托蒽醌（MX）的敏感性，探讨了MAPK通路及p53介导的的细胞线粒体凋亡途径参与的可能机制。结果发现FANCF沉默可通过抑制FANCD2泛素化、及细胞增殖受抑、S期阻滞、凋亡及染色体断裂增加等阻滞乳腺癌细胞FA/BRCA通路功能；同时发现FANCF沉默介导的FA/BRCA通路阻滞可增加MCF-7和MDA-MB-435S对MMC的敏感性，也可增加MCF7细胞和T47D细胞对MX的敏感性，该作用与p38激活进而选择性抑制BCRP表达及JNK激活，诱导p53表达与功能增强，特异性激活细胞线粒体凋亡途径等相关。综上推测FANCF有望成为降低或逆转乳腺癌细胞（特别是p53野生型）耐药性的一个新型靶基因。

中文关键词： 乳腺癌细胞；BCRP；FANCF；FA/BRCA通路；MAPK；

英文摘要： In this study, we observed the effects of FANCF gene silence on biological character in breast cancer, and also examined the influence of FANCF-RNAi on mitomycin C (MMC) or mitoxantrone (MX)-induced antitumoral effect in ER(+) MCF-7 and ER (-) MDA-MB-435S breast cancer cells, or MCF-7 (wt-p53) and T47-D (mut-p53) breast cancer cells, aimed to find the possible mechanisms of MAPK signal pathways and p53- mediated mitochondrial apoptosis involved. The results showed that FANCF silencing by FANCF-shRNA blocked functions of FA/BRCA pathway through inhibition of FANCD2 ubiquitination, as well as inhibited cell proliferation, induced S phase arrest, apoptosis, and chromosome fragmentation in breast cancer cell lines. Meantime, we found that FANCF silencing potentiated the antiproliferative effects of MCF-7 and MDA-MB-435S treated with MMC, or MCF-7 and T47-D treated with MX, which related with activated p38 and specifically decreased BCRP expression, as well as p53- mediated mitochondrial apoptosis via activation of JNK pathway. So it could be presumed that FANCF is hoped to be a new target gene in decreasing or reversing resistance in breast cancer cells, especially in p53 wild-type breast cancer cells.

英文关键词： Breast cancer cells; BCRP;FANCF;FA/BRCA pathway; MAPK