Effects of exogenous fragile histidine triad gene on apoptosis of MGC-803 gastric cancer cells induced by octreotide / 肿瘤

ABSTRACT

Objective:To investigate the effect of exogenous extopic fragile hisdidine triad (FHIT) gene on the apoptosis of gastric cancer cells induced by octreotide and elucidate the underlying mechanism. Methods: Human gastric cancer cell line MGC-803, which was loss of FHIT gene, was transfected with plasmid pRcCMV-FHIT and pRcCMV via lipofectamine mediation. After transfection, Western blotting was used to analyse the expression of FHIT protein in positive cells screened out by G418. The cells were treated with octreotide 10~(-10), 10~(-9), 10~(-8), 10-7, and 10~(-6) mol/L for 24, 48 and 72 h. Cell proliferation was evaluated by MTT assay and apoptosis by flow cytometry. The expression of bcl-2 and bax protein was detected with Western blotting.Results:FHIT protein expression was detected in MGC-803 gastric cancer cells after FHIT gene transfection. After treatment with octreotide 10~(-8) mol/L for 48 h, the apoptotic rate of MGC-803 cells transfected with FHIT gene was (26.777±1.702)%, significantly higher than that in empty vector group and untransfected group [(13.800±0.511)% vs (12.634±0.479)%, F=245.789, P<0.05]. The expression of bcl-2 protein was decreased while the expression of bax protein was increased in FHIT gene transfection group after octreotide treatment. Conclusion:The exogenous FHIT gene and octreotide had strong synergistic effects on apoptosis of MGC-803 cell lines, and their action mechanism may be related to the alteration of the expression of apoptosis-related proteins of bcl-2 family.