Significanee of ginsenoside Rg1 in laryngeal cancer Hep2 cells proliferation and eNOS/iNOS pathways

Objective To investigate the significance of ginsenoside Rg1 in laryngeal cancer Hep2 cells proliferation and endothelial nitric oxide/inducible nitric-oxide synthse (eNOS/iNOS) pathways. Methods In the study, laryngeal cancer Hep2 cells were calculated by ginsenoside Rg1, with drug concentrations as 40 μmol/L, 60 μmol/L, 80 μmol/L , respectively, and cells in different concentrations were all cultured for 24, 48, 72 h as ginsenoside Rg1 group; and a normal training was set as the control group. Methyl thiazolyl tetrazolium method was used to test cell proliferation activity of every group. Flowcytometry analysis was used to analyze the proportion of each cell cycle in each phase. Transcription-polymerase chain reaction method was used to detect cell eNOS and iNOS expression level. Results Rg1 had inhibitory effects on Hep2 cells proliferation, showing time and dose dependent, with 80 μmol/L concentration for the optimum effect. Compared with control group, after been calculated by 80 μmol/L Rg1 for 24, 48, 72 h, Hep2 cells apoptosis rate increased gradually (P<0.01); S phase and G2/M phase cells proportion gradually declined, while G0/G1 phase cell proportion increased (P<0.01). Compared with control group, iNOS levels of ginsenoside Rg1 group decreased, but the content of NO and eNOS was higher. Compared with control group, ginsenoside Rg1 group had higher expression of iNOS mRNA in Hep2 cell lines, and lower eNOS mRNA expression, which was in line with results of spectrophotometric determination. Conclusions Ginsenoside Rg1 can inhibit human laryngeal cancer cells Hep2 cells proliferation, and its mechanism may be related to antioxidant effect of ginsenoside Rg1, by which the eNOS expression is promoted, iNOS expression is inhabited, and the NO activity is improved. Key words: Ginsenoside Rg1; Laryngeal cancer Hep2 cells; Nitric oxide synthase; Nitric oxide