Retinoic acid induces apoptosis in human hepatocarcinoma cell lines

Objective :To investgate the growth inhibition and apoptosis induced by all-trans-retinoic acid(ATRA)in human hepatocarcinoma cell lines.Methods:Human hepatocarcinoma cell lines SMMC- 7721 were cultured with ATRA at the concentration of 0.5ug/ml for 4 days.The cells apoptosis and growth inhibition were assessed by cytomorphology and counting the number of cells to get the rate of growth-inhibited.Cell cycle,tumor genes P53,Fas and Bcl-2 were analyzed with flow cytometry.Results: ATRA inhibited the growth of hepatocarcinoma cells SMMC-7721 in vitro.By using flow cytometry,it was found that apoptosis ceils of total cells were 16% compared with control 6.9%(P0.01),and a sub-G_1 phase cell peak was observed.Morphological observation with light microscope presented apoptosis fea- ture.There was a significant different rate of growth-inhibited,between the two groups(P0.005).The expession of P53 and Fas were up-regulated,and Bcl-2 was down-regulatd when treated with ATRA in contrast to control.Conclusion:ATRA can induce human hepatocarcinoma cell apoptosis.It is a potential preventive and therapeutic agent for hepatoearcinoma.Tumor genes such as P53,Fas and Bcl-2 may be involoved in molecular mechanism of ATRA.