人成纤维细胞生长因子受体2IIIc及其突变型重组腺病毒的获得和在乳腺癌细胞中的表达

获得人成纤维细胞生长因子受体2Ⅲc(FGFR2Ⅲc)及其S252W突变型重组腺病毒,感染乳腺癌细胞MDA-MB-231,为下一步研究FGFR2Ⅲc基因的功能和作用机制奠定基础。以本实验室保存的含FGFR2Ⅲc基因的质粒为模板,PCR扩增得到FGFR2Ⅲc基因,重叠延伸法PCR获得FGFR2ⅢcS252W突变型基因;分别将上述野生型和突变型基因克隆至腺病毒穿梭质粒pAdTrack-CMV上,得到重组穿梭质粒pAdTrack-FGFR2Ⅲc和pAdTrack-FGFR2ⅢcS252W,DNA测序证实。Pme I酶切后分别与腺病毒骨架质粒pAdEasy-1共转化BJ-5183感受态细菌同源重组,得到的重组表达质粒Ad-FGFR2Ⅲc和Ad-FGFR2ⅢcS252W Pac I酶切线性化后转染HEK293A细胞进行重组腺病毒的包装和扩增,通过GFP报告基因观察病毒表达情况。收集重组病毒颗粒并测定滴度,进一步感染乳腺癌细胞MDA-MB-231,RT-PCR和Western blotting方法检测目的基因的表达,3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)法和流式细胞术分析细胞增殖情况。结果表明,成功构建了人FGFR2Ⅲc及其S252W突变型基因的重组腺病毒表达载体,获得的重组腺病毒颗粒能高效感染MDA-MB-231细胞,并表达目的基因。MTT结果显示FGFR2Ⅲc和S252W均能抑制MDA-MB-231细胞增殖,S252W抑制效果更加明显。流式细胞术表明FGFR2Ⅲc和S252W均能使MDA-MB-231细胞周期停滞于G0/G1期,抑制细胞增殖。

Experssion of human FGFR2IIIc and its S252W mutant in MDA-MB-231 breast cancer cells with adenovirus vectors

To study the functions of human Fibroblast growth factor receptor 2IIIc(FGFR2IIIc) gene in cancer cells, breast cancer cells MDA-MB-231 were infected by recombinant adenoviruses containing FGFR2IIIc and its S252W mutant, respectively. FGFR2IIIc gene was amplified from an existing plasmid and its S252W mutant was obtained by overlapping extension PCR. These two genes were separately cloned into the adenoviral shuttle plasmid pAdTrack-CMV, confivmed by DNA sequencing linearized, and co-transformed into Escherichia coli BJ-5183 with the adenoviral vector pAdEasy-1. The resulting recombinant expression vectors Ad-FGFR2IIIc and Ad-FGFR2IIIcS252W were linearized and transfected into HEK293A cells to get adenoviral particles. GFP was used to verify the gene expression. The recombinant adenoviral particles were harvested, titrated, and then infected MDA-MB-231 cells. The expression of FGFR2IIIc and its S252W mutant were examined by RT-PCR and Western blotting, and the effect of these recombinant adenoviruses on MDA-MB-231 cell proliferation was analyzed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry. The results showed the recombinant adenoviral particles could infect MDA-MB-231 cells and express the target proteins. MTT showed that both FGFR2IIIc and its S252W mutant inhibited MDA-MB-231 cell proliferation, but the mutant was more effective. Flow cytometry showed that both FGFR2IIIc and its S252W mutant arrested MDA-MB-231 cell cycle at G0 /G1 phase, resulting in low cell proliferation.