Effects of all-trans retinoic acid on proliferation and apoptosis of EC9706 cells in vitro

Aim: To investigate the inhibition effects of all-trans retinoic acid(ATRA) on proliferation of human esophageal carcinoma cells EC9706 in vitro.Methods:EC9706 cells were processed by variant concentration of ATRA(1×10-6,1×10-5,5×10-5mol/ L).The cellular growth status was observed by using phase contrast microscope.The growth inhibition rate was determined and the growth inhibition rate was detected by using MTT method.The cell morphological alteration was observed after HE staining.The expressions of apoptosis-associated gene Bcl-2 and Bax were detected by immunohistochemical assay(SP technique).Results: After being treated with ATRA,the EC9706 cells had the followingchanges.Compared with control group,the cellular growth rate of ATRA3 group significantly fell,the group doubling time prolonged,and the inhibition rate decreased(P0.05).A series of cell morphological changes was observed,such as more monofilaments and more well-differentiated organelle in experimental groups than those of the control group.Compared with control group,Bax protein expression rate increased,Bcl-2 protein expression rate decreased in ATRA groups(P0.01),especially those of ATRA2,ATRA3 group(P0.05).Conclusion: ATRA could inhibit the growth of EC9707 cells in vitro,and its mechanisms may be related to the expressions of apoptosis-associated protein Bcl-2 and Bax.