Abstract
As a potential chemo-therapeutic agent, all-trans retinoic acid (ATRA) can significantly reverse epithelial-mesenchymal transition (EMT) of hepal-6 hepatocarcinoma cell line in vitro, but the mechanism is unclear. The expression profile of microRNA-200 (miR-200) families is different in hepatocellular carcinoma. In this study, we found that ATRA treatment could up-regulate the expression of miR-200a-3p, 200c-3p, and 141-3p, which were involved in ATRA regulated proliferation and apoptosis of hepal-6 cell, but not colony formation. Meanwhile, miR-200a-3p, 200c-3p, and 141-3p could recovery ATRA inhibited migration and invasion abilities of hepal-6 cells at various levels. miR-200a-3p and 200c-3p prevented ATRA from inducing the differentiation and hepatic functions of hepal-6 cells. Antagomir specific for miR-200a-3p and 200c-3p down-regulated the expression of CK18, but only miR-200a-3p antagomir played prominent role in regulating the expression of these mesenchymal markers, N-Cadherin, Snail and Twist. The transcriptional activities of 8 transcription factors were up-regulated and 35 transcription factors were down-regulated by ATRA. Compared with ATRA group, inhibition of miR-200a-3p, 200c-3p, and 141-3p significantly strengthened the expression of Fra1/Jun (AP1), Ets1/PEA3, Brn3, and Zeb1/AREB6 at varying degrees. Therefore, this result suggested that ATRA may suppress EMT through down-regulating miR-200a-3p, 200c-3p and 141-3p related transcription factors. miR-200 and their downstream genes might be the potentially specific targets for the treatment of hepatocarcinoma.