【摘要】 背景与目的:肿瘤基因治疗中基因特异表达具有重要意义,构建特异表达载体是肿瘤基因治疗的基础。本研究探讨端粒酶催化亚基(humantelomerasereversetranscriptase,hTERT)启动子调控抑瘤素(oncostatinM,osm)基因在端粒酶阳性肿瘤细胞中表达的特异性,以及osm对肿瘤细胞增殖的影响。方法:构建phTERT-osm表达载体,瞬时转染肿瘤细胞;采用RT-PCR法检测外源基因表达,用MTT法检测osm基因表达对肿瘤细胞生长的影响。结果:hTERT启动子调控osm基因在端粒酶阳性HepG2细胞中明显表达,而在正常人胚肺成纤维细胞(humanembryoniclungfibroblast,HEL)中未见表达。osm的表达对端粒酶阳性HepG2、HeLa、Glc和A549细胞的增殖有明显的抑制作用,抑制率为12.4%～46.0%;而对端粒酶阴性的HEL细胞没有明显的影响。结论:hTERT启动子在端粒酶阳性肿瘤细胞中能明显激活phTERT-osm载体表达osm,并抑制肿瘤细胞的生长。更多还原

【Abstract】 BACKGROUND &OBJECTIVE:Specific g ene expression plays an important role in cancer g ene therap y.Construction of specific express ion vector is the basis of cancer g ene therapy.T his study was conducted to explore th e expression specificity of osm(oncostatin M)g ene driven by human telomerase reverse transcriptase(hTERT)g ene promoter in tumor cells with tel omerase activity and to investig ate the g row th inhibitory capability of express ion of osm g ene on telomerase-positive tumor c ells.METHODS :The authors constructed the expression vector of osm g ene afford ed by the hTERT promoter and investig ated its effect on tumors in vitro using re verse transcription polymerase cha in reaction(RT-PCR),transient transfection,and MTT me thod.RESULTS:Expression of extrinsic osm g ene driven by hTERT g e ne promoter was detected in HepG2cel l with telomerase activity,and not de tected in human embryonic lung fibro blast (HEL)cell without telomerase activity.A fter transfection of phTERT-osm,th e proliferation of HepG2,HeLa,Glc,a nd A549cells showed sig nificant inhibitory effect,and the inhibitory rate was 12.4-46%.No inhibitory effect appea red in HEL cell.CONCLUSION:The expression of osm g ene under the c ontrol of hTERT g ene promoter can restrict toxic effect to telomerase-positive tumor ce lls ,and alleviate the toxic effect on normal cells without telomerase activity.更多还原