Notch1信号抑制对成骨肉瘤细胞化疗药物敏感性的影响

目的研究抑制Notch1信号对成骨肉瘤细胞化疗药物敏感性的影响及部分机制。方法将人成骨肉瘤细胞系OS-732按γ-分泌酶抑制剂（GSI）作用与否分为GSI组和对照组;脂质体法转染真核细胞表达质粒;Realtime PCR检测NICD、Hes1mRNA表达;流式细胞仪（FACS）检测Annexin V-PE/7-AAD双标的细胞凋亡;MTT法检测化疗药物对细胞的抑制率。结果 GSI组NICD和Hes1 mRNA均较对照组明显降低（P〈0.01）。GSI组化疗药物导致的瘤细胞抑制率和凋亡率均明显高于对照组。过表达Hes1可减弱GSI诱导的瘤细胞化疗药物敏感性增高。结论 GSI通过抑制Notch1受体激活和下游靶基因Hes1表达促进人成骨肉瘤细胞凋亡,从而增加人成骨肉瘤细胞对化疗药物的敏感性。

Effects of Notch1 signaling inhibition in sensitivity of Osteosarcoma cells to chemotherapy

Objective To study the Effect of Notch1 signaling inhibition in sensitivity of osteosarcoma cells to chemotherapy.Methods The osteosarcoma cells OS-732 were divided into two groups with γ-secretase inhibitor（GSI） or without it.The plasmid was transfected by liposome.NICD and Hes1 mRNA was analyzed by Realtime PCR.The chemosensitivity and apoptosis rate of cells were measured by MTT and flow cytometry respectively.Results The level of NICD and Hes1 mRNA was reduced in group GSI,compared with that in control group（P0.01）.Meanwhile,the chemosensitivity and apoptosis rate of osteosarcoma cells in GSI group were higher than that in control gourp.However,the over-expression of Hes1 decreased the chemosensitivity of osteosarcoma cells which increased by GSI treatment.Conclusion GSI enhances the sensitivity of osteosarcoma cells to chemotherapy through promoting the cell apoptosis,which is induced by inhibition of Notch1 receptor activity and target gene Hes1 expression.