中文摘要：

目的 探讨苯并（a）芘[B（a）P]诱导的人胚肺成纤维细胞（HELF）中p53蛋白、p53磷酸化水平及亚细胞分布和活化蛋白-1（AP-1）活性的改变，以及p53与AP-1的上下游关系。方法 转染p53小干扰RNA p53 siRNA质粒（p53-H）、载体CMV的HELF细胞（HELF／CMV）和转染AP-1荧光报告质粒的HELF细胞（AP-H）无血清培养48h后，加入2μmol/L B（a）P作用24h，用Western blot及免疫荧光法检测细胞中p53蛋白及p53磷酸化的改变，利用细胞核、细胞浆分离技术观察其亚细胞定位，用荧光检测法检测AP-1的相对活性。用AP-1的化学抑制剂cureumin抑制其活性，用p53的化学抑制剂pifithrin-α（PFT）抑制其表达，观察了二者的上下游关系。结果2μmol/L B（a）P作用24h后细胞内p53蛋白及p53蛋白20位丝氨酸磷酸化水平增加，并且主要分布在细胞核内；AP-1的活性增加。抑制AP-1活性后，对B（a）P诱导的p53蛋白含量增加没有明显的影响；抑制p53表达后，对B（a）P诱导的AP-1活性的增加没有明显影响。结论 B（a）P通过AP-1非依赖的信号通路引起人胚肺成纤维细胞p53蛋白含量的增加。

英文摘要：

Objective To investigate changes of p53 expression, p53 phosphorylation, and their subcellular localizations and activated protein 1 （AP-1） activity on human embryo lung fibroblasts （HELF） induced by benzo（a）pyrene （B（a）P） , and relationships between p53 and AP-1. Methods Cells transfected with p53 small interference RNA （p53 siRNA） plasmid （p53-H）, CMV vector （HELF/CMV） and AP- 1 luciferase reporter plasmid （AP-H） were cultured with serumfree RPMI-1640 for 48h, then treated with 2μmol/L B （a）P for 24h. Changes of p53 expression and p53 phosphorylation were checked by immunofluorescence and Western blot assay. The subcellular localizations of p53 and phosphorylated p53 were checked by cytoplasmic and nuclear extraction. AP-1 relative activities were detected by luciferase assay. Chemical inhibitors of p53 （pifithrin-α （PFT）） and AP-1 （curcumin） were used to observe relationships of p53 and AP-1. Results The cells were treated with 2vmol/L B（a） P for 24h, expression of p53 and phosphorylated p53 at 20 site were significantly increased, and they were entirely localized in the nucleus. AP-1 activities significantly increased after B （a） P treatment. When AP-1 activities were inhibited by curcumin, overexpression of p53 induced by B（a）P was not markedly changed. When p53 expression was inhibited by PFT, AP-1 activities were not significantly changed. Conclusion Overexpression of p53 in HELF induced by B（a）P could be through AP-1 independent pathways.