Takeyama Y, Tanimoto T, Hoshijima M, Kaibuchi K, Ohyanagi H, Saitoh Y, Takai Y
FEBS Lett. 1986 Mar 3;197(1-2):339-43. doi: 10.1016/0014-5793(86)80353-2.
A small amount (50-200 microM) of deoxycholate (DOC), a colon tumor-promoting bile acid, did not show a direct effect on protein kinase C activity in a cell-free system, but enhanced fibroblast growth factor (FGF)-induced diacylglycerol formation and protein kinase C activation in Swiss 3T3 cells. DOC potentiated both reactions induced by submaximal doses of FGF but showed little effect on the maximal levels of the reactions. DOC alone was inactive in eliciting both reactions in the absence of FGF. DOC did not affect the binding of FGF to the cells. Since it has been described that diacylglycerol serves as a messenger for the activation of protein kinase C in the action of FGF in Swiss 3T3 cells [(1985) FEBS Lett. 191, 205-210], these results suggest that a small amount of DOC increases the sensitivity to FGF of diacylglycerol formation and thereby potentiates protein kinase C activation in this cell line. This action of DOC was in marked contrast to that of 12-O-tetradecanoylphorbol-13-acetate, a potent tumor-promoting phorbol ester, which directly activated protein kinase C in cell-free and intact cell systems.
少量（50 - 200微摩尔）的脱氧胆酸盐（DOC），一种促进结肠肿瘤的胆汁酸，在无细胞体系中对蛋白激酶C活性未显示直接作用，但在瑞士3T3细胞中增强了成纤维细胞生长因子（FGF）诱导的二酰基甘油形成和蛋白激酶C活化。DOC增强了亚最大剂量FGF诱导的两种反应，但对反应的最大水平影响很小。在没有FGF的情况下，单独的DOC在引发这两种反应方面没有活性。DOC不影响FGF与细胞的结合。由于已经描述在瑞士3T3细胞中FGF作用过程中二酰基甘油作为蛋白激酶C活化的信使[（1985年）欧洲生物化学学会联合会快报。191, 205 - 210]，这些结果表明少量的DOC增加了二酰基甘油形成对FGF的敏感性，从而增强了该细胞系中蛋白激酶C的活化。DOC的这种作用与12 - O - 十四酰佛波醇 - 13 - 乙酸酯（一种有效的促肿瘤佛波酯）的作用形成显著对比，后者在无细胞和完整细胞体系中直接激活蛋白激酶C。
