RESUMO
Objective To explore the effects of all-trans-retinoic acid (ATRA) on the proliferation of human lung adenocarcinoma cell line A549 and the expression of APLNR (apelin receptor) gene.Methods The inhibition of proliferation of human lung adenocarcinoma cell lines A549 cultured in vitro with or without ATRA was measured by MTT (methyl thiazolyl tetrazolium,MTT) method.The morphological changes in the cells were observed by light microscopy.The cell cycle and apoptosis were analyzed by flow cytometry.The levels of APLNR,cyclin D1 and p16 proteins were detected by western blot.Results After treatment of ATRA,the proliferation of A549 cells was obviously inhibited in dose-and time-independent manner (P ＜ 0.01).The cell morphology was significantly changed.The cycle of A549 cells was blocked at G0/G1 phase and the apoptosis rate was increased.With the increasing concentration of ATRA,the expressions of cyclin D1 and APLNR were down-regulated but the expression of p16 was up-regulated (P ＜ 0.01).Conclusion ATRA could inhibit the proliferation of A549 cells by retardant cell cycle of A549 cells at G0/G1 phase and inducing the apoptosis,and down-regulate the expression of APLNR gene.