Nrf2信号通路在亚砷酸钠诱导支气管上皮细胞恶性转化中的作用  

Role of nuclear factor E2 related factor 2 signaling pathway in malignant transformation induced by sodium arsenite

作　　者：谷仕艳[1] 陈承志[1] 蒋学君[1] 张遵真[1] 

机构地区：[1]四川大学华西公共卫生学院环境卫生学教研室,成都610041

出　　处：《卫生研究》2016年第3期356-361,共6页Journal of Hygiene Research

基　　金：国家自然科学基金面上项目(No.81372945)

摘　　要：目的构建亚砷酸钠(NaAsO_2)诱导人支气管上皮(HBE)细胞恶性转化的模型,探讨核转录因子-E2类相关因子2(Nrf2)信号通路在恶性转化过程中的作用。方法以2.5μmol/L NaAsO_2染毒HBE细胞,以四氮唑盐比色(MTT)法、克隆形成和划痕侵袭等实验鉴定细胞恶性转化;蛋白免疫印迹实验检测恶性转化过程中细胞内Nrf2及其下游靶基因醌氧化还原酶1(NQO1)和血红素单加氧酶-1(HO-1)的表达水平。结果随NaAsO_2染毒代数的增加,HBE细胞逐渐表现增殖失控,染毒25代(As-HBE-T25)和50代(As-HBE-T50)的克隆形成率分别为1.33%和4.47%,侵袭能力为正常HBE的2.04倍和4.17倍;同时,细胞浆和细胞核中的Nrf2表达水平均下降,As-HBE-T25细胞浆和细胞核中的Nrf2表达水平分别为正常HBE的0.83倍和0.81倍,As-HBE-T50为0.42倍和0.63倍;NQO1在As-HBE-T25和As-HBE-T50中的表达为正常HBE的0.84倍和0.59倍,HO-1则为0.75倍和0.48倍(P<0.05)。结论 NaAsO_2慢性染毒诱导了人支气管上皮细胞恶性转化,可能的机制为NaAsO_2持续抑制Nrf2信号通路,使NQO1和HO-1表达水平降低,从而引起细胞恶性增殖。Objective To construct the malignant transformation model of human bronchial epithelial（ HBE） cell line by exposing to low level of sodium arsenite and determine if the nuclear factor E2 related factor 2（ Nrf2） signaling pathway is involved in this process. Methods HBE cells were continuously exposed to 2. 5 μmol / L sodium arsenite and malignant transformation occurred as evidenced by the MTT assay,colony formation assay and cell migration assay. Western blot was used to evaluate the expression of Nrf2,quinone oxidoreductase 1（ NQO1） and heme oxygenase-1（ HO-1） during sodium arsenite-induced transformation of HBE cells. Results MTT assay demonstrated that the proliferation of HBE cells was out of control with increasing passages of sodium arsenite exposure. In As-HBE-T25 and As-HBE-T50 cells,the cell invasion ability was2. 04 and 4. 17 times than that in normal HBE cells and colony formation rate was 1. 33%and 4. 47%,respectively. At the same time,the expression level of Nrf2 in the cytoplasm and nucleus were both significantly lower compared with the control group in a passagedependent manner（ P〈0. 05）. Also,the expression of NQO1 and HO-1,downstream of Nrf2 target proteins,were also decreased with the expression of Nrf2. Conclusion The transformation of HBE cells induced by chronic exposure to sodium arsenite is mediated by decreased Nrf2 level and its downstream NQO1 and HO-1 protein,which subsequently promote the malignant proliferation.

关 键 词：恶性转化 核转录因子-E2类相关因子2 醌氧化还原酶1 血红素单加氧酶-1 

分 类 号：R730.231.1[医药卫生—肿瘤] R994.6[医药卫生—临床医学]