硒化卡拉胶联合表阿霉素对肝癌HepG-2细胞增殖及细胞周期的影响

摘要

目的：观察硒化卡拉胶（KSC）和表阿霉素（EPI）联合应用对人肝癌HepG-2细胞生长及细胞周期的影响，并探讨其作用机制。方法 MTT（噻唑蓝）比色法测定KSC和EPI对HepG-2细胞增殖的影响，计算半数抑制浓度IC50值及金式指数q判断两者联合作用效果；用倒置显微镜观察细胞形态学变化；流式细胞仪检测药物对细胞周期的影响；Western blot法检测细胞周期蛋白Cyclin A和Cdc25A、细胞周期蛋白依赖性激酶Cdk2的表达水平。结果 KSC和EPI可明显抑制HepG-2细胞增殖，且有剂量依赖性。联合组的抑制效果更显著，且优于单一用药组。EPI单独用药48 h的IC50值为3.612 mg/L，与30 mg/L KSC联合用药的IC50值降至0.807 mg/L，q值判断两药联合表现为相加作用。倒置显微镜观察给药后细胞形态发生变化，联合组细胞膜破裂呈坏死状。流式细胞术结果表明，两药均可导致S期周期阻滞。Western blot 结果显示两药均可使Cyclin A、Cdc25A和Cdk2蛋白表达下调，联合给药组下降更明显。结论 KSC和表阿霉素可抑制肝癌HepG-2细胞增殖，引起细胞周期S期阻滞，两药联合具有相加效应，这与其调节细胞周期相关蛋白的生成关系密切。%Objective To investigate the effect and mechanism of kappa-selenocarrageenan (KSC) combined with epirubicin (EPI) on the proliferation and cell cycle of a human hepatoma cell line HepG-2. Methods The anti-proliferative effect on HepG-2 cells was determined by MTT assay. IC50 values were calculated and King’s formula was used to evaluate the interaction of drug combination. The morphological changes were observed under inverted microscopy. Cell cycle was measured by flow cytometry. Expression of cyclin A, cdc25A and cdk2 were detected by western blotting. Results KSC and EPI alone could inhibit cell proliferation on HepG-2 cells in a dose-dependent manner, and the combination group inhibited more significantly than the two drugs did alone. Q values demonstrated an additive effect. IC50 value of EPI on HepG-2 cells for 48 h was 3.612 mg/L, it decreased to 0.807 mg/L while combined with 30 mg/L KSC. In addition, morphologies of HepG-2 cells were changed after exposure to the drugs, and cell membranes were ruptured and necrosis-like in combination group. Flow cytometry results demonstrated that KSC and EPI both made HepG-2 cells S phase arrest. Western blotting analysis revealed that KSC and EPI could down-regulate cyclin A, cdc25A and cdk2 expression, and the combination group decreased more significantly. Conclusion KSC and EPI have the anti-proliferative effect on HepG-2 cells and induce S phase arrest, which may be related to the proteins associated with cell cycle closely. And the combination therapy of KSC and EPI can produce an additive effect.