高氧刺激下PAC1诱导乳腺癌细胞凋亡的机制探讨  

Mechanism of PAC1 in signaling oxidative stress-induced apoptosis of MDA-MB435

作　　者：吴晶晶[1] 吕会艳[1] 耿丽[1] 

机构地区：[1]郑州大学第一附属医院肿瘤科,郑州450052

出　　处：《临床肿瘤学杂志》2010年第10期879-882,共4页Chinese Clinical Oncology

摘　　要：目的初步探讨高氧刺激下PAC1对人乳腺癌细胞株MDA-MB435的凋亡诱导作用及其机制。方法通过脂质体法转染目的质粒pcDNA3.1(+)/PAC1进入人乳腺癌细胞株MDA-MB435,筛选稳定表达PAC1的细胞克隆,并使用Western blotting法鉴定高表达PAC1的MB435细胞克隆。应用台盼蓝染色法检测不同细胞在H2O2处理后的存活率变化,同时进一步使用Western blotting法检测MB435/PAC1细胞克隆经H2O2处理后其ERK1/2磷酸化的水平。结果在细胞克隆MB435/PAC1-C2和MB435/PAC1-C6中均有高水平的PAC1表达,这些高表达PAC1的肿瘤细胞经高氧化合物H2O2刺激后细胞存活率相对于对照组均明显降低(P<0.01),而且PAC1的高表达可以引起细胞内MAPK激酶ERK1/2的活性受到抑制,使磷酸化水平降低。结论 PAC1可以通过抑制ERK1/2的磷酸化水平而介导细胞对高氧刺激的反应,从而诱导细胞发生凋亡。Objective To study the mechanism of PAC1 in signaling apoptosis of MDA-MB435 cell line under oxidative stress.Methods Gene transfection of pcDNA3.1（＋）/PAC1 on MDA-MB435 cells was conducted by lipofectamine and stable cell clones expressing high level PAC1 were selected,and the expression level of PAC1 were tested by Western blotting.PAC1-mediated induction of apoptotic cell death and dephosphorylation of ERK in response to H2O2 were examined by trypan blue exclusion and Western blotting.Results There were high levels of PAC1 protein in the two stable clones expressing ectopic PAC1,and PAC1 could induce cell apoptosis and suppress the activity of ERK1/2 in response to H2O2 treatment（P0.01）.Conclusion PAC1 acts in the apoptotic pathway to elicit cancer cell killing under oxidative stress through suppressing the MAP kinase survival pathway.

关 键 词：PAC1 MAPKS 细胞凋亡 高氧刺激 

分 类 号：R737.9[医药卫生—肿瘤]