尼美舒利对脱氧胆酸诱导的HT-29人结肠癌细胞增殖的抑制作用的研究

目的观察尼美舒利对脱氧胆酸(DCA)诱导的人结肠癌HT-29细胞增殖的抑制作用,探讨其可能的机制。方法200μmol/L DCA加到HT-29细胞培养液中,同时给予不同浓度尼美舒利(50、75和100μmol/L),采用MTT法测定细胞增殖;RT-PCR法检测环氧合酶-2(COX-2)mRNA,免疫组化染色法检测细胞COX-2表达,放免法检测前列腺素E2(PGE2)含量。结果DCA作用HT-29细胞6h,COX-2蛋白表达阳性率较对照组明显升高(64.2%±6.2%比7.1%±1.9%),PGE2合成增加(23.9ng/L±1.3ng/L比10.5ng/L±0.9ng/L),尼美舒利对DCA诱导的HT-29细胞作用6h可抑制细胞增殖,并可抑制DCA诱导的COX-2mRNA表达,并抑制PGE2合成,上述作用均呈浓度-时间依赖性。结论尼美舒利可抑制DCA诱导的HT-29人结肠癌细胞增殖,抑制COX-2mRNA表达和蛋白表达及PGE2合成,这可能是尼美舒利抑制HT-29细胞增殖的机制之一。

Study on the effects of Nimesulide on inhibiting HT-29 human colon cancer cell proliferation induced by deoxycholic acid

Objective To investigate the effect of Nimesulide on inhibiting HT-29 human colon cancer cell proliferation induced by deoxycholic acid(DCA).Methods The Nimesulide with concentration of 50,75 or 100μmol/L were added into the HT-29 human colon cancer cell culture media containing 200 μmol/L DCA.The effects of Nimesulide on cell proliferation were studied by the method of MTT.RT-PCR was applied to measure the expression of cyclooxygenase-2(COX-2) mRNA.Cellular immunochemical stain was applied to label COX-2 protein expression.Concentration of prostaglandin E2(PGE2)was measured by radioimmunoassay.Results HT-29 cells were incubated with DCA for 6 h.COX-2 experssion of cells were increased prominent compared to controls(64.2 ng/l±6.2 ng/l vs.7.1 ng/l±1.9 ng/l).The level of PGE2 were increased(23.9 ng/l±1.3 ng/l vs.10.5 ng/l±0.9 ng/l).Nimesulide reduced the proliferation rate of HT-29 induced by DCA over 6 h.Both COX-2 mRNA expression and the level of PGE2 were inhibited by Nimesulide and in a concentration-time dependent manner.Conclusion Nimesulide can inhibit the proliferation of HT-29 human colon cancer cell induced by DCA.Nimesulide can also suppress the expression of COX-2,and decrease the production of PGE2.These data provide new insights into the mechanism of its anti-cancer properties.