舒林酸抑制人胃腺癌细胞增殖及诱导凋亡

Effects of Sulindac on growth inhibition and apoptosis induction in human gastric cancer cells

目的在体外对舒林酸抗人胃腺癌细胞增殖和凋亡诱导作用及其机制进行初步研究.方法采用人胃腺癌细胞株 MKN45,MKN28作为研究对象.体外药物敏感试验(MTT)检测不同浓度和作用时间的舒林酸对细胞的增殖抑制效应;分别用 Hoechst33258细胞核荧光染色、透射电镜和 DNA 琼脂糖凝胶电泳观察舒林酸诱导的细胞凋亡改变;应用 Western 斑点免疫印迹法观察经舒林酸2rnmol·L^(-1)和4mmol·L^(-1)作用24h 后细胞内环氧化酶-2(COX-2)和凋亡抑制蛋白 Bcl-2表达程度的变化.结果舒林酸对人胃腺癌细胞 MKN45,MKN28的杀伤率随着剂量的增大和作用时间的延长而增加,舒林酸对不同类型的细胞杀伤率不同.舒林酸能够诱导人胃腺癌细胞 MKN45,MKN28产生凋亡,凋亡诱导作用的强弱同样具有时间和剂量依赖性,而且对不同类型胃癌细胞的凋亡诱导效应有显著差异.经舒林酸2 mmol·L^(-1)和4mmol·L^(-1)作用24h 后,MKN45细胞内 COX-2和 Bcl-2蛋白比未经舒林酸作用的细胞表达明显减少,而 MKN28细胞内 COX-2和 Bcl-2蛋白的表达未出现明显变化.结论舒林酸在体外对人胃腺癌细胞株 MKN45和 MKN28有良好的增殖抑制作用,诱导凋亡是其抑制胃癌细胞增殖的重要作用机制.舒林酸对人胃腺癌细胞的抑制和凋亡诱导作用与其抑制细胞内环氧化酶-2,并进而抑制 Bcl-2的表达有关,并可能与胃癌细胞的分化状态有关.

AIM To characterize the effects and its mechanisms of Sulindac in inducing growth inhibition and apoptosis in human gastric cancer cell lines. METHODS The human gastric cancer cell lines MKN45 and MKN28 were included in the study.Antiproliferative effects were measured by MTT assay,and apoptosis was determined by Hoechst33258 staining,electronograpy and DNA fragmentation.The protein of cyclooxygenase-2(COX-2)and Bcl-2 were detected by Western dot blotting. RESULTS Sulindac could inhibit the growth of gastric cells in a dose-and time-dependent manner.The effects of growth inhibition were different between gastric cancer cell lines. The apoptosis of gastric cell lines could be induced by Sulindac in a dose-and time-dependent manner.The apoptosis rates were also different.After 24h of incubation with Sulindac at 2mmol·L^(-1)and 4 mmol·L^(-1),the expression of COX-2 and Bcl-2 were reduced in MKN45 cells but not in MKN28 cells. CONCLUSION Sulindac could inhibit effectively the growth of two gastric cell lines in vitro by apoptosis induction,which was associated with regression of COX-2 and Bcl-2.The different effects of apoptosis in gastric cancer cells may be related to the differentiation of the cells.