维甲酸诱导基因RA538诱导人胃癌细胞系凋亡及其分子机制的研究

Studies on the apoptosis process and molecular mechanism of recombinant RA538 adenovirus on a human gastric cancer cell line——SGC7901

目的 研究全反式维甲酸 (retinoicacid ,RA)RA5 38诱导胃癌细胞的凋亡作用及其分子机制。方法 采用MTT、DNA梯度降解试验、原位末端标记、RT PCR、Westernblot等方法 ,对RA5 38重组腺病毒 (Ad)在人胃癌细胞系中生物学作用及其分子机制进行体内外研究。结果 Ad RA5 38对SGC790 1细胞能产生明显的生长抑制效应 ,诱导SGC790 1细胞凋亡。Ad RA5 38生长抑制率为 76 3%。Ad RA5 38对SGC790 1细胞产生的抑瘤效应及诱导凋亡作用是c myc、bcl 2、bax、cyclinD1等一系列基因表达变化及其相互作用的结果 ,其中对c myc及bax表达的调节作用是在RNA和蛋白水平。而对p5 3、p16、TGase、ras基因的表达没有明显影响。经Ad RA5 38处理的SGC790 1细胞致瘤性消失。Ad RA5 38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 ,生长抑制率为 6 0 7%。结论 Ad RA5 38对胃癌细胞具有显著的生长抑制及凋亡诱导作用。其作用可能与抑制c myc、bcl 2、cyclinD1基因及刺激bax基因表达的机制相关。与p5 3、p16、TGase及ras基因的表达无明显关系。

Objective Studies on the apoptosis effects and molecular mechanism of recombinant RA538 adenovirus on human gastric cancer cell line in vitro and in vivo . Methods Human gastric cancer cell line was treated respectively with Ad RA538 and Ad LacZ. MTT, DNA ladder, TUNEL, FCM, RT PCR and Western blot were used. Results Ad RA538 could strongly inhibit cell growth and induce apoptosis of SGC7901 cells. The growth rate of the Ad RA538 infected SGC7901 cells was inhibited by 76.3%. A series of expressions of c myc, bel 2, bax and cyclin D1 and their interactions of each other resulted in SGC7901 cells growth inhibition and apoptosis, which were induced by RA538. Regulations for the expressions of c myc and bax were at levels of RNA and protein, and there were no significant effects on expressions of p53, p16 TGase and ras. Treated with RA538, SGC7901 cells lost tumorigenicity. Experimental therapy on the nude mice bearing subcutaneously transplanted tumor of SGC7901 cells showed that intratumor injections of Ad RA538 inhibited the growth of the tumors. Ad RA538 treated tumors were inhibited by 60.66%, compared with that of the tumor injected with Ad LacZ and mock. Conclusion Ad RA538 can inhibit growth and induce apoptosis of gastric cancer cells in vitro and in vivo. RA538 makes effects on the expressions of c myc, bcl 2, cyclin D1 and bax genes and leads to gastric cancer cells apoptosis finally.