Inhibitory effect of fibroblast growth factor-21 on the carcinogenesis of L02 cells induced by diethylnitrosamine

Objective To investigate the inhibitory effect of fibroblast growth factor-21 (FGF-21) on the carcinogenesis of L02 cells induced by diethylnitrosamine (DEN) .Methods L02 cells were cultured and treated with different concentrations of DEN (1, 10, 20, 50, 100, and 150 μmol/L) .MTT assay was used to measure the influence of DEN on the viability of L02 cells, and an appropriate stimulation concentration of DEN (20 μmol/L) was selected for further study.The malondialdehyde (MDA) and superoxide dismutase (SOD) detection kits were used to measure the levels of MDA and SOD in L02 cells treated by DEN (20μmol/L) and normal L02 cells.Then L02 cells were divided into model control group (treated with 20μmol/L DEN and PBS) , low-dose FGF-21 group (20 μmol/L DEN + 1 μmol/L FGF-21) , and high-dose FGF-21 group (20 μmol/L DEN + 2 μmol/L FGF-21) .The levels of MDA and SOD were measured after 12 hours of cell culture.Real-time PCR and Western blot were used to measure the expression of βKlotho (KLB) , and Western blot was used to measure the level of phosphorylated protein kinase B (p-AKT) .The t-test was used for comparison of continuous data between two groups; an analysis of variance was used for comparison between multiple groups, and the least significant difference t-test was used for further comparison between two groups.Results There was a significant increase in the level of MDA and a significant reduction in the level of SOD after L02 cells were treated with DEN (t = 9.336 and 16.281, P = 0.011 and 0.004) .Compared with the model control group, the low-and high-dose FGF-21 groups had a significant reduction in the level of MDA and a significant increase in the level of SOD (P <0.05) , and compared with the low-dose FGF-21 group, the high-dose FGF-21 group had a significantly lower level of MDA and a significantly higher level of SOD (P = 0.030 and 0.042) , and there was a significant difference between two groups.The high-and low-dose FGF-21 groups had significantly higher mRNA expression of KLB than the model control group (P < 0.001) , and the high-dose FGF-21 group had significantly higher mRNA expression of KLB than the low-dose FGF-21 group (P < 0.001) , and there was a significant difference between two groups; the protein expression of KLB showed the same trend.The model control group had a significantly higher level of p-AKT than the other two groups (P < 0.05) , and the high-dose FGF-21 group had a significantly lower level of p-AKT than the low-dose FGF-21 group (P < 0.05) .Conclusion DEN can increase oxidative stress in L02 cells.By upregulating the expression of KLB, FGF-21 can reduce the level of p-AKT, inhibit oxidative stress in L02 cells induced by DEN, and thus inhibit the development of hepatocellular carcinoma.