MiR-200a inhibits cell proliferation and EMT by down-regulating the ASPH expression levels and affecting ERK and PI3K/Akt pathways in human hepatoma cells.

The primary objective of this study was to investigate the role of miR-200a in cell proliferation and epithelial-mesenchymal transition (EMT) through regulating targeting aspartate-β-hydroxylase (ASPH), which may further affect the activation of ERK/PI3K/Akt pathway. Liver cancer and adjacent tissues were collected from 72 cases of liver cancer patients with surgery in our hospital. In this study, the mRNA expression level of miR-200a was significantly decreased by real-time PCR (RT-PCR) detection. ASPH expressions, however, had an opposite tendency compared to that of miR-200a. We found a significantly negative correlation between miR-200a expressions and ASPH expressions. The survival rate of liver cancer patients with the low expressed ASPH was significantly higher than those with the high expressed ASPH. RT-PCR and Western blot results showed that low expressed miR-200a and highexpressed ASPH were found in liver cancer cell lines. Further research discovered that miR-200a transfection could significantly decrease the relative luciferase activity when it was integrated with ASPH 3'-untranslated region (3'-UTR) in HepG2 cells. Cell Counting Kit (CCK-8) detection showed that treatment with miR-200a mimics reduced cell viability, while the over-expressed ASPH increased cell viability by regulating the c-mycmrna (c-Myc) and Cyclin-D1 expressions. The EMT-related genes including E-Cadherin, N-Cadherin and Vimentin expressions were significantly increased, whereas the over-expressed ASPH exerted the opposite effects. In addition, extracellular signal regulated kinase (ERK), phosphoinositide-3-kinase (PI3K) and serine threonine kinase (AKT) were suppressed by miR-200a mimics. In conclusion, miR-200a inhibits cell proliferation and EMT in human hepatoma cells by targeting ASPH and affecting ERK and PI3K/Akt signaling pathways.