Abstract:Purpose To study the effect of all-trans retinoic acid (ATRA) in the proliferation of human ovarian cancer cells. Methods HO8910 human ovarian cancer cell lines were cultured in vitro and treated with different concentrations of all-trans retinoic acid for 1, 2 or 3 days. Cell proliferation was evaluated by MTT assay.Cell cycle was analayzed by flow cytometry (FCM). The expression of retinoic acid receptor α mRNA was detected by reverse transcription- polymerase chain reaction (RT-PCR). Results Different concentrations of all-trans retinoic acid could inhibit the growth of HO8910 cells(P<0.05) in a time and dose-dependent manner.All-trans retinoic acid increased the rates of G1 and decreased the rates of S and G2/M(P< 0.05), and therefore,it decreased cells proliferation index (PI﹡)(P<0.05).It could up-regulate the expression of retinoic acid receptor α mRNA(P<0.05),then inhibit proliferation of HO8910 cells. Conclusion All-trans retinoic acid could inhibit the proliferation of human ovarian cancer cells HO8910,the molecular basis may be associated with the up-regulated mRNA of retinoic acid receptor α .