肝癌细胞DNA损伤时三结构域蛋白28磷酸化对肝癌细胞生存能力的影响

Effect of trim28(ser473)phosphorylation on viability of hepatocellular carcinoma cells duringDNA damage

目的观察当肝癌细胞的DNA损伤时三结构域蛋白28(Trim28)磷酸化对其生存能力的影响.方法将Hepg2细胞系分为SB203580+UV组及UV组.用紫外线(UV)照射Hepg2细胞建立Hepg2细胞DNA损伤的模型,SB203580+UV组在UV照射后使用Trim28磷酸化抑制剂SB203580处理细胞.通过蛋白质印迹法(Western blot)检测上述处理后两组细胞的Trim28、磷酸化Trim28 ser473(p-Trim28 ser473)的表达;通过噻唑蓝(MTT)实验观察上述处理后Hepg2细胞的生存能力.结果SB203580+UV(0.96±0.16)组与UV组(0.94±0.13)的Trim28表达比较,差异无统计学意义(t=-0.190,P>0.05);,SB203580+UV组p-Trim28(0.32±0.04)明显低于UV组(0.72±0.05),差异有统计学意义(t=8.500,P<0.05);紫外线照射后24、48、72 h UV组细胞生存率[(95±7)%、(62±10)%、(35±6)%]明显高于SB203580+UV组[(85±7)%、(37±4)%、(20±3)%],差异有统计学意义(t=-2.326、-5.212、-4.577,P<0.05).结论当肝癌细胞DNA损伤时抑制Trim28(ser473)磷酸化可以降低癌细胞的生存能力.

Objective To observe effect of Trim28(ser473)phosphorylation on viability of hepatocellular carcinoma(HCC)cells during DNA damage.Methods To divide Hepg2 cells into 2 groups as SB203580+UV group and UV group.Hepg2 cells were modeled for DNA damage by UV(Ultraviolet)irradiation.SB2035804-UV group was treated with Trim28 phosphorylation inhibitor SB203580 after UV irradiation.Expression of Trim28 and phosphorylation-Trim28 ser473(P-Trim28 ser473)were detected by westemblot experiment.The viability of Hepg2 cells were observed by methyl thiazol tetrazolium(MTT)experiment.Results Compared with UV group(0.94±0.13),the expression value of Trim28 in SB203580+UV group had no significant difference(t=-0.190,P>0.05).Value of phosphorylation-Trim28 in SB203580+UV group(0.32±0.04)was obviously lower than UV group(0.72±0.05),the difference had statistical meaning(t=8.500),P<0.05);The 24,48 and 72 hours after UV irradiation,the cell survive rate of UV group[(95±7)%,(62±10)%,(35±6)%]is higher than SB203580+UV group[(85±7)%,(37±4)%,(20±3)%].The difference has statistical meaning(t=-2.326,-5.212,-4.577,P<0.05).Conclusion The viability of HCC cells during DNA damaged can be reduced by inhibition for Trim28 phosphorylation.