Ⅰ型γ分泌酶抑制剂抗恶性胶质瘤的体外/体内实验研究  

in vitro / in vivo Studies of Anti-tumor Effects of γ-secretase Inhibitor-Ⅰ on Glioblastoma Cell Lines

作　　者：林骏[1] 杨进城[2] 张兴梅[3] 罗深秋[1] 

机构地区：[1]南方医科大学细胞生物学教研室广东省骨与软骨再生医学重点实验室,广州510515 [2]广州军区广州总医院,广州510010 [3]南方医科大学神经生物学教研室,广州510515

出　　处：《热带医学杂志》2010年第10期1176-1179,F0004,共5页Journal of Tropical Medicine

基　　金：广东省自然科学基金面上项目(No.7005144;7005145)

摘　　要：目的 明确γ-分泌酶抑制剂(γ-secretase inhibtor,GSI)对恶性胶质瘤细胞体外、体内的抗瘤作用,并初步探讨其机制。方法 通过MTT法观察GSI-Ⅰ对胶质瘤细胞株U87及U251生长曲线的抑制作用;以DAPI染色法观察GSI-Ⅰ作用后是否导致细胞凋亡;用荧光定量RT-PCR法检测GSI-Ⅰ对胶质瘤细胞中Notch信号的阻断作用,并通过Western-blot检测GSI-Ⅰ对胶质瘤细胞内抗凋亡蛋白Akt的表达及磷酸化水平的影响;最后,采用裸鼠成瘤实验验证GSI-Ⅰ对胶质瘤细胞体内增殖的抑制作用,以及GSI-Ⅰ对瘤组织的毒性作用。结果 GSI-Ⅰ可显著抑制U87及U251细胞的生长曲线,并直接诱导细胞凋亡。GSI-Ⅰ可有效阻断细胞内Notch信号通路转导,并下调抗凋亡蛋白Akt的活性。动物实验结果显示,GSI-Ⅰ预处理可降低U251细胞的体内成瘤能力,而瘤周注射GSI-Ⅰ可导致瘤组织大面积坏死。结论 GSI-Ⅰ有明确的体外、体内抗恶性胶质瘤效应,其可能机制为下调细胞内Notch信号通路及抗凋亡通路,但具体分子机制仍需进一步研究。Objective To elucidate the anti-tumor effects of a γ-secretase inhibitor（GSI）on human glioblastoma cells and explore the underlying mechanisms.Methods MTT assays were performed to examine the inhibitory effects of GSI-Ⅰ on the growth curves of two glioblastoma cell lines U87 and U251.Cellular apoptosis induced by GSI-Ⅰ treatment was determined by DAPI staining.Quantitative real-time RT-PCR（qRT-PCR）was performed to evaluate the inhibitory effects of GSI-Ⅰ on Notch signaling of the cells.Additionally,the expression and phosphorylation level of the anti-apoptotic protein Akt was examined by Western-blot.Finally,subcutaneous xenografts experiments in athymia nude mice were carried out to test the anti-tumor effects of GSI-Ⅰ in vivo.Results GSI-Ⅰ significantly inhibited the growth curves of U87 and U251 cells and induced apoptosis.Notch signaling was abrogated by GSI-Ⅰ and activation of Akt was also downregulated.The in vivo anti-tumor effects of GSI-Ⅰ on glioblastoma cells were confirmed by subcutaneous xenografts experiments.Conclusions GSI-Ⅰ exerted anti-tumor effects on glioblastoma cells in vitro and in vivo.Down regulation of Notch signaling and the anti-apoptotic Akt signaling might be involved in the anti-tumor effects,however further studies are needed to elucidate the underlying mechanisms.

关 键 词：Γ-分泌酶抑制剂 胶质瘤 细胞凋亡 NOTCH 

分 类 号：R739.41[医药卫生—肿瘤]