Inhibitory effect of all-trans-retinoic acid on proliferation of human retinal pigment epithelial cells in vitro

Objective To investigate the effects of all-trans-retinoic acid(ATRA) on proliferation of cultured human retinal pigment epithelium(RPE) cells and the probable mechanisms.Methods Cultured human RPE cells were treated with various concentrations(10-9,10-8,10-7,10-6 and 10-5 mol·L-1) of ATRA at different time points(6,12,24,48,72 and 96 h).Cell proliferation was evaluated by cell count and MTT colorimetric assay,and cell cycle analysis was performed by flow cytometry.Results The cell viability rates of ATRA treated group were decreased obviously,compared with control groups(P0.01).The inhibitory rates of RPE cell proliferation had positive correlation with ATRA dose and time of action(r1=0.9926,P0.05;r2=0.9647,P0.05).In ATRA groups,compared with non-ATRA treated groups,the cell number in G1 phase was increased(P0.05),while in G0/G1 phase was decreased(P0.05).Conclusion ATRA could inhibit the proliferation of human RPE cells in a dose-dependent and time-dependent manner by arresting cell cycle.