Effects of IL-12 combined with GM-CSF on apoptosis of H22 hepatoma cells / 中国综合临床

ABSTRACT

Objective To investigate the effects of granulocyte macrophage colony-stimulating factor (GM-CSF) combined with interleukin-12 (IL-12) genes on apoptosis of hepatoma cells.Methods The hepatoma cell lines were cultured in vitro and were divided into four groups GM-CSF transfection group,IL-12 transfection group,GM-CSF and IL-12 co-transfection group,negative control group (empty load group),respectively.The PIB-CMV3-GM-CSF and PIB-CMV3-IL-12 eukayotic expression vector was built,and 36 h after transfection,fluorescence microscope was used to detect the transfection effect;the expression level of IL-12,GM-CSF,p53,p38 and C-JUN mRNA were detected by RT-PCR,and Western blot was used to examine the expression level of IL-12,GM-CSF,p53,p38 and C-JUN protein.In addition,the flow cytometry was applied to detect cell apoptosis.Results Through fluorescence microscope,green fluorescence was observed in cells of GM-CSF transfection group,IL-12 transfection group,GM-CSF and IL-12 co-transfection group,indicating that the plasmid has successfully transferred into cells.In addition,the expression of p53mRNA in empty load group,GM-CSF transfection group,IL-12 transfection group,GM-CSF and IL-12 co-transfection group were 1.2±0.10,4.3±0.98,4.2±0.34,9.2±0.87,and the protein expression were 1.0±0.10,3.6±0.34,3.8±0.30,5.0±0.60.Compared with the empty load group,the expression level of p53 mRNA and protein were significantly increased in the three plasmid transfection groups (P<0.01).The expression of p53 mRNA and protein were significantly increased in co-transfection group than GM-CSF group and IL-12 group (P<0.01),while in the comparison with GM-CSF transfection group and IL-12 transfection group,the expression level of p53mRNA and protein in the co-transfection group could be improved to a higher degree(P<0.01).Meanwhile,p38 C-JUN mRNA expression levels in empty load group,GM-CSF transfection group,IL-12 transfection group,GM-CSF and IL-12 co-transfection group were as follows 7.5± 0.9,3.5±0.45,3.7±0.25,1.0±0.11,while p38protein expression levels were 10.1±1.03,6.1± 0.67,7.1 ± 0.61,1.0 ± 0.12,respectively,C-JUN mRNA expression levels were 11.2 ± 1.20,4.1 ± 0.19,3.3 ± 0.30,1.0 ± 0.01,separately,C-JUN protein expression levels were 2.25 ± 0.2,1.8 ± 0.13,1.4 ± 0.12,1.0 ± 0.09.P38, C-JUN mRNA and protein levels were significantly reduced in the three plasmid transfection groups compared with the empty load group (P<0.01).The expression of p38,C-JUN mRNA and protein were reduced to a lower degree in co-transfection group than in GM-CSF transfection group and IL-12 transfection group (P<0.01).Flow cytometer showed that the hepatoma cell apoptosis rate of the empty load group,GM-CSF transfection group,IL-12 transfection group,co-transfection group were (3.43±0.9)%,(5.87±1.02)%,(7.32±1.1)%,(17.47±2.11)%,the rates of the three plasmid transfection groups were significantly higher than that of the empty load group (P<0.01).And the apoptosis rate was significantly increased in the co-transfected group compared with other plasmid groups (P<0.01). Conclusion The combination of GM-CSF and IL-12 could significantly accelerate the apoptosis of hepatoma cells by up-regulating the expression of p53,and down-regulating the expression of p38 and C-JUN.