AFP的亚细胞定位及对肿瘤细胞生长的影响

摘要

目的 观察甲胎蛋白(AFP)在不同肿瘤细胞中的亚细胞定位及对肿瘤细胞生长的影响.方法 运用免疫荧光的方法观察内源性AFP在HeLa细胞、QGY-7703细胞、MCF-7细胞中的亚细胞定位.将构建的表达AFP的质粒pcDNA3-AFP及AFP腺病毒siRNA干涉载体Adv-AFP siRNA作用于QGY-7703细胞,MCF-7细胞,运用MTT,集落形成实验检测细胞增殖状况.结果 免疫荧光显示,内源性的AFP在 HeLa细胞、QGY-7703细胞、MCF-7细胞均只在细胞质中表达.pcDNA3-AFP 使QGY-7703的细胞活性增加了21%(P＜0.05)及集落形成能力增加了32 %(P＜0.01),MCF-7实验组比对照组细胞活性降低了30%(P＜0.01),克隆形成能力降低82 %(P＜0.01).Adv-AFPsiRNA使QGY-7703的细胞活性降低了22 %(P＜0.05),平均克隆形成能力降低52 %(P＜0.01),MCF-7细胞活性提高了24.5 %(P＜0.05),克隆形成能力提高了89 %(P＜0.01).结论 内源性的AFP只在细胞质中表达.AFP能促进QGY-7703细胞的增殖及克隆形成能力,而在MCF-7细胞中发挥相反的作用.腺病毒介导的内源性的AFP表达的下调能降低QGY-7703的增殖,却增加了MCF-7的细胞活性及克隆形成能力.%Objective To observe the subcellular localization of endogenous AFP in different tumor cells and the effect of AFP on tumor cell proliferation.Methods Subcellular localization of endogenous AFP in HeLa,QGY-7703,and MCF-7 was detect by use of immunofluorescence.Cell activity and colony formation ability were measured in QGY-7703,MCF-7 which were treated with pcDNA3-AFP or Adv-AFPsiRNA.Results Immunofluorescence revealed that endogenous AFP is expressed only in cytoplasm.Ectogenous AFP enhanced cell proliferation(21 %,P＜0.05) and colony formation ability(32 %,P＜0.01) of QGY-7703 cells,but decreased cell proliferation(30 %,P＜0.01)and colony formation ability(82 %,P＜0.01) of MCF-7 cells.In contrast,down-regulation of endogenous AFP by Adv-AFPsiRNA reduced proliferation to 22 %(P＜0.05)and colony formation to 52% (P＜0.01) in QGY-7703 cells,but increased cell proliferation to 24.5 % (P＜0.05) and colony formation to 89 % (P＜0.01) in MCF-7 cells.Conclusion Endogenous AFP is expressed only in the cytoplasm.Ectogenous AFP enhances cell proliferation and colony formation ability of QGY-7703 cells,but not MCF-7 cells.