Abstract: AIM: To investigate the effects of lipoxygenase inhibitor, on proliferation in hepatocellular carcinoma cell line HepG2 and MEK/ERK signaling pathway in vitro.METHODS: Different concentrations of nordihydroguaiaretic acid (NDGA) were used to treat HepG2 cell. The proliferation inhibition was analysed by alive cell count, MTT assay, the mRNA expression intensity of MEK1, MEK2, ERK1, ERK2 were examined by RT-PCR.RESULTS: NDGA can inhibit HepG2 cell proliferation viability in the dose-dependent manner. The mRNA expression intensity of MEK1, MEK2, ERK1, ERK2 showed a trend of decreasing while the concentrations of nordihydroguaiaretic acid increased. The mRNA expression intensity of MEK1 was significantly decreased than the control at any concentrations (P<0.05), meanwhile the mRNA expression intensity of MEK2, ERK1, ERK2 was significantly decreased than the control at concentrations of 100 μmol/L or 200 μmol/L (P<0.05).CONCLUSION: NDGA can inhibit proliferation of HepG2 cell line, the mechanism of which may be due to down-regulating MEK/ERK signaling pathway.

Key words: Lipoxygenase inhibitors, Hepatocellular carcinoma, Cell proliferation, Extracellular signal-regulated kinase