抑瘤素M对人乳腺癌细胞增殖与凋亡的影响

The effects of oncostatin M （OSM） gene on proliferation and apoptosis of human breast cancer cells in vitro

目的 以逆转录病毒为载体,研究抑瘤素M（oncostatin M,OSM）基因对人乳腺癌细胞株（michigan cancer foundation-7,MCF-7）生长抑制作用.方法 以最佳感染剂量携带OSM基因的逆转录病毒感染MCF-7人乳腺癌细胞,反转录酶-聚合酶链锁反应（reverse transcription-polymerase chain reaction,RT-PCR）和酶联免疫吸附测定法（enzyme-linked immunosorbent assay,ELISA）检测目的基因在MCF-7人乳腺癌细胞中的转录；对感染后的MCF-7人乳腺癌细胞,以四甲基偶氮唑盐比色法（methyl thiazolyl tetrazolium,MTT）检测OSM基因对肿瘤细胞的生长抑制作用,流式法检测OSM基因诱导肿瘤细胞的凋亡效应,赫斯特（Hochest）染色法检测凋亡细胞的核形态改变,并用RT-PCR法进一步检测肿瘤细胞中凋亡相关基因的表达.结果 逆转录病毒载体能介导OSM基因在MCF-7人乳腺癌细胞中的转录及表达后,能够显著的抑制肿瘤细胞的生长（MTT法,P=0.0162,P＜0.05）并诱导其凋亡（膜联蛋白/碘化丙啶双染法,P=0.02,P＜0.05）.结论 OSM基因对MCF-7细胞有显著的抑制作用,其作用的机制可能与其上调凋亡促进蛋白Bax和Caspase3,下调凋亡调控基因Bcl-2有关.

Objective To study the inhibition effects of oncostatin M （OSM） gene on human breast cancer cell line（michigan cancer foundation-7,MCF-7）.Methods MCF-7 cells were infected with the optimized dose of retrovirus expressing OSM.Expression of the target gene was determined by reverse transcriptionpolymerase chain reaction（RT-PCR） and enzyme-linked immunosorbent assay（ELISA）.Methyl thiazolyl tetrazolium （MTT） assay was employed to examine growth inhibition effect of OSM gene on MCF-7 cells.Cell apoptosis was determined by flow cytometry.The morphologic changes of nucleus was detected by Hochest staining,in addition,the expression of apoptosis related genes in tumor cells were further detected by RT-PCR.Results OSM gene was well expressed in human breast cancer MCF-7 cell by retrovial vetor and it could significantly inhibit the growth of MCF-7 cell（MTT,P =0.0162,P ＜ 0.05） and induce its apoptosis （Annexin V/PI,P =0.02,P ＜ 0.05）.Conclusion OSM gene has significant inhibitory effects on MCF-7 cells,which mechanism might be related to the upregulation of Bax and Caspase3 and the downregulation of Bcl-2.