蛙皮素对胃癌细胞BGC-823的生长调控作用

Effect of Bombesin on growth of human gastric cancer cell line BGC-823

目的:观察蛙皮素(BBS)对人低分化胃癌细胞株BGC-823的生长调控作用,测定细胞内环磷酸腺苷(cAMP)含量、蛋白激酶C(PKC)活性及PKC亚型的表达,探讨受体后信息传导途径。方法:BGC-823细胞在含10%小牛血清的RPMI 1640培养液中,于37℃、5%CO2条件下培养,分别加入不同浓度的BBS,应用MTT法观察细胞的增殖程度;应用放射免疫分析方法测定细胞内cAMP含量;应用[γ-32p]ATP掺入外源性底物的方法测定PKC活性;应用Westernblot方法分析PKC亚型α、β1、β2及ε的表达。结果:BBS能促进BGC-823细胞的生长,且与剂量呈正相关(r=0.747,P<0.05);BBS能促进细胞内cAMP的产生及PKC活性的增加,PKCα表达明显增加,而β1、β2及ε则无明显表达。结论:BBS对胃癌细胞BGC-823的生长、细胞内cAMP产生及PKC活性增加有重要作用。

Objective：To observe the effect of Bombesinon on the growth of a poorly differentiated human gastric cancer cell line BGC-823 and to explore the post-receptor signal transduction pathway by determining the content of intracellular cyclic adenosine monophosphate （cAMP）,the activity of protein kinase C （PKC）,and the expression of PKC isofonns α,β1,β2,and e, Methods：BGC-823 cells were cultured in RPMI 1640 medium containing 10% FCS in atmosphere of 5% carbon dioxide at 37℃,and then were treated with different concentrations of Bombesin or its antagonist, The viability and proliferation were determined with MTT assay. The content of intracellular cAMP was detected by radioimmunoassay. The activity of PKC was measured by incorporating [ γ-^37p ]-ATP into exogenous substrate,and the expressions of PKC isoforms was analyzed with Westem blotting. Results：Bombesin promoted the growth of BGC-823 cells in a dose-dependent manner, which can be inhibited significantly by the antagonist of Bombesin. Bombesin increased the content of intracellular cAMP and the activity of PKC. The expression of PKC-α significantly increased,but no expression of PKC-β1 ,β2,and ε was found. Condusion：Bombesin may play an important role in the proliferation,production of intmcellular cAMP,and activity of PKC in poorly differentiated gastric carcinoma cell line BGC-823.