AG1024对肝癌细胞系增殖与凋亡的影响

Effects of AG1024 on hepatocellular carcinoma cell lines

目的探讨胰岛素样生长因子Ⅰ型受体（IGF-IR）酪氨酸激酶阻断剂AG1024（3-溴-5-叔丁基-4-羟基苯叉苹果酸腈）对人肝癌癌细胞的增殖抑制作用和凋亡诱导作用。方法采用MTT、流式细胞术、细胞侵袭实验、RT—PCR和Westernblot等方法检测在不同浓度（0～40μmol／L）的AG1024作用下，人肝癌细胞系HepG2和SMMC-7721的细胞形态学及分子生物学特性的改变。结果MTT检测显示，AG1024剂量依赖性地抑制肝癌细胞的增殖。流式细胞术提示，AG1024明显促进肝癌细胞的凋亡。Transwell小室侵袭实验显示，AG1024能明显抑制肝癌细胞系HepG2和SMMC-7721的侵袭能力，与对照组比较差异有统计学意义（P〈0．05）。RT—PCR结果显示，肝癌细胞中IGF—IR呈高表达，不同浓度AG1024作用后，剂量依赖性地增加细胞色素C的表达。Western blotting结果显示，AG1024降低胞外途径信号调节激酶（extracellular signal—regulated kinase，ERK）的磷酸化水平，下调procaspase-3的表达，而总ERK保持不变。结论AG1024阻断胰岛素样生长因子1型受体，从而阻断其下游的信号传导途径，抑制肝癌细胞的增生，诱导凋亡。

Objective Tyrphostin AG1024 （3-Bromo-5-t-butyl-4-hydroxybenzylidenemalonitrile） is a specific insulin like growth factor type I receptor tyrosine kinase blocker, this study is to investigate the effect of AG1024 on the proliferation and apoptosis of hepatoeellular carcinoma cell lines. Methods Treated with AG1024 on varied concentrations （0 - 40 μmoL/L）, human hepatocellular carcinoma cell lines HepG2 and SMMC-7721 were observed for morphological and molecular biology changes, the effect of AG1024 on the cell lines proliferation invasion ability as well as apoptosis was evaluated. Results MTT showed that AG1024 dose-dependently inhibited the proliferation of hepatocellular carcinoma cells, flow eytometry suggested that AG1024 significantly promoted cell lines apoptosis, the cell invasion assay indicated that AG1024 significantly inhibited cell＇s invasion ability. RT-PCR showed over-expression of IGF-IR in liver cancer cells, and AG1024 dose-dependently increased the expression of cytochrome C. According to the results of Western blotting, the phosphor-ERK and procaspase-3 were down-regulated while the total ERK remained unchanged. Conclusion AG1024 as a specific IGF-IR blocker blocks the downstream signaling cascade and thus inhibits the proliferation of hepatocellular carcinoma cells and induces cell＇s apoptosis.