bax和p53基因转染对人舌癌细胞增殖和凋亡的影响

目的 探讨诱导凋亡的bax基因和p53抑癌基因共转染对人癌细胞增殖和凋亡的作用。方法 构建pSV-CIP-bax-CAT嵌合基因。在其bax基因上游含人al(Ⅰ）型胶原基因的第一内含子２１７bp片段（＋８２２－＋１０９３）和３１７bp启动子片段，经阳离子转染试剂ＤＯＳＰＥＲ介导，分别用pSV-CIP-bax-CAT转染、pSV-CIP-bax-CAT和pSV-p53－ＣＡＴ共转染培养的人舌癌Ｔca8113细胞系（ＬＣＣ）。结果 免疫狭缝印迹和ＥＬＩＳＡ检测证实，转染组和共转染组和共转染组比对照的bax和p53基因表达量明显增加，ＭＴＴ显色分析、ＴＵＮＥＬ荧光显微镜和流式细胞仪监测结果显示，bax基因或p53基因均具抑制ＬＣＣ增殖和诱导凋亡的作用（bax组和bax p53组的抑制率分别为２３.9%和２６.1%)。结论 人al(Ⅰ）型胶原基因的顺式作用元件能促使bax基因在ＬＣＣ异位表达；bax与p５３共转染４８小时，对ＬＣＣ抑制增殖和诱导凋亡的作用具明显协同效应。

Effect on proliferation and apoptosis of human lingual carcinoma cells cotransfected by bax and p53 genes]

OBJECTIVE: To investigate the effects on proliferation and apoptosis of human cancerous cells cotransfected by bax apoptosis-inducing gene and p53 tumor suppressor gene. METHODS: The chimeric gene pSV-CIP-bax-CAT was constructed in which bax gene was flanked upstream by a 217 bp fragment(+822(-)+1093) of the first intron and a 317 bp promoter fragment of human a 1(I) collagen gene. Human lingual carcinoma cell line Tca 8113 (LCC) in culture was respectively transfected with pSV-CIP-bax-CAT, and cotransfected with pSV-p53-CAT and pSV-CIP-bax-CAT by using the transfection reagent DOSPER. RESULTS: Immuno-slot blot and ELISA demonstrated that the expression of bax and p53 genes increased remarkably in the transfected and cotransfected LCC, compared with the controls (LCC transfected with pSV-CIP-CAT and LCC). MTT colorimetric assay, TUNEL fluorenscence microscopy and flow cytometry showed that foreign bax or p53 gene inhibited the LCC growth and induced apoptosis (23.9% and 26.1% of inhibitory rate by bax gene and p53 plus bax genes respectively). CONCLUSION: The ectopic expression of the bax gene in the LCC promoted by the cis-acting elements of human a1 (I)collagen gene has obviously synergistic effect on the proliferation and apoptosis of the LCC contransfected with p53 gene plus bax gene for 48 hours.