蛙皮素对结肠癌细胞株调控及其受体后信息传导

The effect of growth regulation and postreceptor signal transduction of bombesin on human colon cancer cell line

目的 研究蛙皮素对人结肠癌细胞株的生长调控及受体后的信息传导途径。方法 观察蛙皮素对人结肠癌细胞株cloneA细胞的生长调控 ;应用液体闪烁测量法、γ 闪烁记数仪分别测定细胞内三磷酸肌醇及环磷酸腺苷含量 ;用荧光测定细胞内游离Ca2 + 浓度 ;参考TaKai法测定蛋白激酶C活性。结果 浓度为 10 -8～ 10 -5mol/L的蛙皮素明显促进cloneA细胞的生长 (P <0 .0 1)以及使上述物质含量及活性增加。此作用可被蛙皮素受体拮抗剂所阻断。结论 蛙皮素能促进cloneA细胞生长 ,可能是通过磷酸肌醇和腺苷环化酶途径 。

Objective To investigate the effect of growth regulation and postreceptor signal transduction of bombesin(BBS) on human colon cancer cell line. Methods Low differentiated clone A cells of human carcinoma were treated with different concentrations of BBS and the growth status was observed. Intracellular inositol 1,4,5 trisphosphate(IP 3) and cyclic adnosine monophosphate(cAMP) were extracted, and their concentrations were measured by liquid scintillation technique and gamma scintillation counter. Intracellular free calcium concentration was detected by loading Fura 2/AM and fluorescence technique .Protein kinase C(PKC) was extracted from cytosol and membrane, and the activity of both parts was determined with TaKai method. Results Proliferation of clone A cell was observed with different concentrations of BBS(10 -8 ～10 -5 mol/L). The cell growth could be inhibited by BBS receptor antagonist. The production of intracellular IP 3,Ca 2+ ,cAMP and the activity of PKC both in cytosol and membrane were increased with BBS. These effects could also be inhibited by BBS receptor antagonist. Conclusion These results suggest that the growth of clone A cell can be promoted by BBS. The effect is possibly mediated by BBS receptor in cytomembrane. The postreceptor signal transduction might be performed by the pathways of inositol phosphate and adenyl cyclase. PKC might also be involved in this process.