PI3K p85α蛋白表达缺失联合5-FU对大肠癌细胞的促凋亡作用

The proapoptotic effect of combination PI3K p85α depletion and 5-FU treatment on colorectal cancer cells

探讨RNA干扰靶向抑制PI3K p85α蛋白表达联合5-FU对大肠癌LoVo细胞的促凋亡作用。方法复苏培养PI3K p85α干扰组LoVo细胞(PI3Kp85ɑ/RNAi-LoVo)和LoVo对照组细胞,Western blot鉴定干扰效果,MTT法检测5-FU对两组细胞的半数抑制浓度(IC50),Annexin-FITC标记法检测细胞凋亡。结果 Western blot结果显示LoVo干扰组细胞PI3K p85α蛋白抑制率为59%,MTT结果显示干扰组细胞5-FU的IC50值(4.57±0.16)μmol/L明显低于对照组细胞5-FU的IC50值(8.07±0.30)μmol/L(P=0.000),细胞凋亡实验显示,干扰组细胞对5-FU诱导凋亡的敏感性增加(P=0.000)。结论 PI3K p85α蛋白表达缺失联合5-FU可促进大肠癌LoVo细胞凋亡,为基因治疗和化学药物联合治疗大肠癌提供新的策略。

Objective To investigate the proapoptotic effect of combination PI3K p85α depletion via RNA interference and 5-FU treatment on colorectal cancer cells. MethodsPI3K p85α/RNAi-LoVo cells and LoVo control cells were recovered and cultured in RPMI1640,supplemented with 10% fetal calf serum and 500 μg/mL G418.Western blot analysis was used to determine the RNA interference effect.The 50% inhibitory concentration（IC50） value of 5-FU was evaluated by MTT assay.Annexin V-FITC Kit was used to determine the apoptosis. ResultsWestern blot analysis showed that the inhibited rate of PI3K p85α protein was 59%.Compared with the control cells,IC50 of 5-FU in PI3K p85α/RNAi-LoVo cells obviously decreased（P=0.000）.Depletion of PI3K p85α sensitized LoVo cells to 5-FU induced apoptosis（P=0.000）. ConclusionCombination PI3K p85α depletion and 5-FU treatment could promote apoptosis of LoVo cells.It may be a new therapeutic strategy for gene therapy and chemotherapy of colorectal cancer.