Purpose: Dihydromyricetin (DHM) is a flavonoid isolated from Hovenia dulcis. DHM have been reported to have hepatoprotective and anti-tumor effects. The purpose of this study was to elucidate the anti-tumor effect and the mechanism of DHM in human hepatocellular carcinoma cell line, Huh-7.
Methods: Huh-7 cells were cultivated with DHM (0 - 100 μM) for 72 hours. We evaluated that the cell proliferation in Huh-7 cells treated with DHM using a MTS assay. The mRNA and protein levels of Ki-67, cyclinD1, and caspase 3 were analyzed using a real time-RT-PCR or a western blot analysis. The protein levels and phosphorylation of ERK, c-fos, c-jun as MAPK signaling were confirmed.
Results and discussion: Although DHM (1 - 10 µM) did not changed cell proliferation, 30 µM and 100 µM of DHM significantly decreased in Huh-7 cells.
Ki-67 and cyclin D1 mRNA levels were decreased in DHM-treated Huh-7 cells. However, caspase 3 mRNA levels was not increased. Cyclin D1 protein levels were also significantly decreased and caspase 3 protein levels were not increased in DHM-treated with Huh-7 cells; these suggest that DHM inhibited cell proliferation and did not effect the apoptotic protein, caspase 3.
The total ERK and pERK were significantly decreased in Huh-7 treated with DHM. However, the level of p-c-fos, and p-c-jun were tended to decrease. DHM may related to the decreases of HCC cell proliferation through the ERK.