介导RA538与反义c-myc腺病毒对肿瘤细胞的作用及其分子机理

目的　比较全反式维甲酸诱导基因 RA5 38及反义 c- myc对人胃癌细胞的生物学特性 ,并探讨其作用的分子机理。方法　采用细胞生长曲线、DNA梯度降解试验、原位末端标记、流式细胞仪、逆转录 -聚合酶链反应、蛋白质印迹分析、裸鼠致瘤性、裸鼠皮下移植瘤模型实验等方法 ,对 RA5 38、反义 c- myc重组腺病毒在人胃癌细胞系 (SGC790 1)中的生物学作用及其分子机理进行体内外研究。结果　 RA5 38及反义 c- myc重组体腺病毒 (Ad- RA5 38及 Ad- ASc- myc)对 SGC790 1细胞生长抑制率分别为 76 .3%和 44 .1%。 DNA梯度降解试验、原位末端标记、流式细胞仪显示 Ad- RA5 38及 Ad- ASc- myc诱导 SGC790 1细胞凋亡。它们均能抑制SGC790 1细胞 c- myc、bcl- 2、cyclin D1基因表达 ,并刺激 bax基因表达 ,对 p5 3、p16、TGase、ras基因的表达没有影响。经 Ad- RA5 38及 Ad- ASc- myc处理的 SGC790 1细胞致瘤性消失。Ad- RA5 38及 Ad- ASc- myc对裸鼠皮下移植瘤模型瘤内注射能有效降低肿瘤的生长速度 ,生长抑制率分别为 6 0 .7%和 6 8.9%。结论　 Ad-RA5 38、Ad- ASc- myc对胃癌细胞具有显著的生长抑制及凋亡诱导作用。其作用是 c- myc、bcl- 2、bax、cyclin D1等一系列基因表达变化及其相互作用的结果 ,与 p5 3、p16、TGa

The effects of recombinant RA538 and antisense c-myc adenovirus on tumor cells and the molecular mechanism concerned

Objective Compare the biological effects of recombinant RA538 and antisense c myc adenovirus on human gastric cancer cell line (SGC7901) and explore the molecular mechanism in vitro and in vivo. Methods SGC7901 cells were treated with Ad RA538, Ad AS c myc or Ad LacZ. MTT, DNA ladder, TUNEL and FCM, RT PCR, Western blot analysis, the tumorigenicity in nude mice and experimental therapy of the nude mice were used. Results Ad RA538 and Ad ASc myc could strongly inhibit cell growth and induce apoptosis of SGC7901 cells. The growth of the Ad RA538 and Ad ASc myc infected SGC7901 cells were inhibited by 76.3% and 44.1% respectively. The over expression of RA538 and ASc myc could down regulate expression of c myc, bcl 2 and cyclinD1 gene and up regulate expression of bax gene, but it could not regulate expression of p53, p16, TGase, and ras gene. The tumorigenicity of Ad RA538 or Ad ASc myc in nude mice showed that three of three mice failed to form tumor,compared with Ad LacZ and parent SGC7901 cells from 7 to 30 days. Experimental therapy of the nude mice bearing subcutaneous tumor of SGC7901 cells showed that intratumor instillation of Ad RA538 and Ad ASc myc inhibited the growth of the tumors. Ad RA538 and Ad ASc myc treated tumors were inhibited by 60.7% or 68.9% respectively, compared with the tumor injected with Ad LacZ and mock. Conclusion The expression of Ad RA538 and Ad ASc myc can inhibit growth and induce apoptosis of gastric cancer cell in vitro and in vivo. RA538 and ASc myc relate to c myc, bcl 2, cyclinD1 and bax gene closely and have noticeable biologic effects on gastric cancer cells.