土槿乙酸抑制体外人胃癌细胞的生长

Pseudolaric acid B inhibits growth of human gastric carcinoma cells in vitro

目的探讨土槿乙酸（PLAB）对人胃癌细胞生长的影响及机制。方法RT-PCR法检测MGC803细胞中PPARγ mRNA的表达；MTT法检测细胞的生长；Hoechst333342／PI双染色法和DNA凝胶电泳检测细胞凋亡；流式细胞术检测细胞周期。结果PLAB（0．1～10μmol／L）作用MGC803细胞72h显著抑制细胞增殖。PLAB（10μmol／L）作用后，G2期细胞随着作用时间的延长而增加，呈明显的G2期阻滞。作用72h后，细胞出现核染色质凝集，DNA片断化等凋亡特征。在MGC803细胞中过氧化物酶增殖物激活受体γ（PPARγ）表达较弱，经PLAB（10μmol／L）作用48h表达水平显著增加（P〈0．01）。结论PLAB能在体外明显诱导MGC803细胞G2期阻滞和凋亡，该作用可能与PPARγ激活有关。

Objective To investigate the effect of pseudolaric acid B （PLAB） on growth of human gastric carcinoma cells in vitro. Methods The expression of PPARγ was detected by RT-PCR; the effect of PLAB on cell growth was tested by MTT; Hoechst33342/PI and DNA gel electrolysis were employed to examine apoptosis; cell cycle was checked by flow cytometry. Results When treated with 0. 1 - 10 μmmol/L PLAB for 72, the proliferation of MGC803 cells was significantly inhibited. The proportion of MGC803 cells at G2 phase was significantly increased when treated with 10 μmmol/L PLAB after 48 h, and showed an apparent G2 phase arrest. After treatement with PLAB for 72, typical apoptotic changes were observed. The expression of PPARγ was at a low level in MGC803 cells and up-regulated when treated with 10 tunmoL/L PLAB for 48 h （ P 〈 0.01 ）. Conclusion Activation of PPARγ induces G2 phase cell cycle arrest and cell apoptosis in vitro.