二十二碳六烯酸增强5氟尿嘧啶对人肝癌细胞的细胞毒活性

The effect of docosahexaenoic acid on the cytotoxic activity of 5-Fu and its mechanism in human HepG2 cell

目的研究二十二碳六烯酸(DHA)联合5氟尿嘧啶(5-Fu)对肝癌细胞增殖、凋亡的影响。方法 CCK8法检测DHA联合5-Fu对肝癌细胞HepG2细胞增殖的影响;流式细胞仪检测DHA联合5-Fu对HepG2细胞凋亡的影响;RT-PCR检测DHA及5-Fu处理后HepG2细胞凋亡相关基因Bcl-2、Bax表达的变化。结果 DHA联合5-Fu较单用5-Fu能更加明显抑制HepG2细胞的增殖,凋亡率分别为23.7%,13.2%。经DHA处理后HepG2细胞中Bcl-2表达下降,联合5-Fu后Bcl-2表达进一步减少,Bax表达则无明显改变。结论 DHA联合5-Fu能有效的抑制Bcl2的表达,从而发挥抑制肝癌细胞增殖、诱导肝癌细胞凋亡的效应。

Objective To study the mechanism of docosahexaenoic acid inducing the apoptosis of human hepatocellular carcinoma cell line HepG2 by the combined use of DHA and 5-fluorouracil. Methods CCK8 assay was used to investigate the effect of DHA on HepG2 cells in vitro. Flow cytometry （FCM） was used to examine the effects of both combined drugs or 5-fluorouracil on apoptosis of HepG2 cells. Reverse transcription polymerase chain reaction （RT-PCR） was applied to detect the mRNA expressions of Bcl-2, Bax in HepG2 cells. Results The combined drugs significantly inhibited cell proliferation compared with 5-fluorouracil. FCM indicated that the apoptosis of HepG2 cells was significantly higher after exposure to combined drugs compared with 5-fluorouracil（P 0.05）. The mRNA level of Bcl-2 was significantly decreased, especially in the combined drug treatment. But DHA has no significant effects on the mRNA level and protein secretion of Bax. Conclusion The combined use of DHA and 5-Fluorouracil could significantly downregulate Bcl-2 expression, and thereby induce the apoptosis of human hepatocellular carcinoma cell line HepG2.