Investigation Of Potentialization Of Chrysin On The Cytotoxicity Induced By TRAIL In Human Gastric Cancer SGC-7901 Cell Line

Objective To investigate whether chrysin(ChR) enhance cytotoxicity induced by recombinant human solubility TNF-related apoptosis-inducing ligand(TRAIL) through inhibiting NF-κB activity in human gastric cancer SGC-7901 cell line.Methods Human gastric cancer SGC-7901 cell line and human gastric mucosa GES-1 cell line were cultured in vitro. The cell viability was determined using MTT assay. The sub-G1 cell percentage was examined by flow cytometry using PI fluorescence staining. The characteristic features of cell apoptosis was certified by DNA agarose gel electrophoresis. The expressions of phosphorylated IκBαand NF-κB(p65) protein were analyzed by Western blot.Results The MTT assay showed that IC50 of cell viability inhibition in human gastric cancer SGC-7901 cells by ChR and TRAIL alone for 48h were 134μmol/L and 402ng/mL, respectively. However, IC50 by TRAIL treatment for 48h pretreated with ChR(40μmol/L) for 30 minute was 47ng/mL, and the CI value for ChR and TRAIL was 0.4676. IC50 of cell viability inhibition in immortalization dipoid human gastric mucosa GES-1 cells by ChR and TRAIL alone for 48h or TRAIL treatment for 48h pretreated with ChR(40μmol/L) for 30 minute were 747μmol/L,1348ng/mL and 845ng/mL, respectively. The CI value for ChR and TRAIL was 1.7579. Flow cytometry(FCM) analysis with PI stainning indicated that the sub-G1 cell percentage in human gastric cancer SGC-7901 cells by ChR(40μmol/L) and TRAIL(100ng/mL) alone for 48h were 4.65%±0.58% and 3.60%±0.16%, respectively. However, sub-Gl cell percentage after TRAIL (100ng/mL) treatment for 48h pretreated with ChR(40μmol/L) for 30 minute was 49.87%±4.27%. The sub-G1 cell percentage in human gastric mucosa GES-1 cells by ChR(40μmol/L) and TRAIL(100ng/mL) alone for 48h or TRAIL(100ng/mL) treatment for 48h pretreated with ChR(40μmol/L) for 30 minute were 3.09%±0.24%,4.11%±0.22%, and 4.34%±0.095%, respectively. There was not significant difference in comparison with solvent group(2.19%±0.06%). The ladder band could be shown in DNA agarose gel electrophoresis after treatment with TRAIL(100ng/mL) for 48h pretreated with ChR(40μmol/L) for 30 minute in human gastric cancer SGC-7901 cells. Western blot analysis indicated that ChR inhibited expression of NF-κB(p65) protein and depressed the phosphorylation level of IκBαprotein in SGC-7901 cells, in a time-and concentration-dependent manner.Conclusion1. Chrysin at suboptimal concentration possess augmentation of TRAIL induced cytotoxicity of in human gastric cancer SGC-7901 cells.2. The potentialization of TRAIL induced cytotoxicity of human gastric cancer SGC-7901 cells by ChR is associated with inhibiting the expression of NF-κB(p65) protein and depressing the phosphorylation level of IκBαprotein.