应用流式细胞技术和免疫组织化学方法，测试了微囊藻毒素、佛波酯及苯巴比妥钠对ＢＡＬＢ／ｃ３Ｔ３细胞周期和增殖细胞核抗原表达的影响。结果表明，３种非遗传毒性致癌物均可不同程度地诱发Ｓ期细胞比例增高，并呈一定的剂量－反应关系。佛波酯０．１μｇ／ｍｌ时Ｓ期细胞达５７．９％，表明半数以上的细胞进入ＤＮＡ合成期。增殖细胞核抗原表达在受试物作用下随剂量增高阳性表达明显加强。提示诱导细胞异常增殖可能是此３种非遗传毒性致癌物致癌作用的原因之一。 Flow cytometry and immunohistochemistry were used to test the effects of microcystin, phorbol ester and phenobarbital on BALB/c3T3 cell cycle and PCNA expression. The results showed that the three non-genotoxic carcinogens can induce different degrees of S phase cells increased in varying degrees, and showed a dose-response relationship. Phorbol ester 0.1μg/ml S phase cells up to 57.9%, indicating that more than half of the cells enter the DNA synthesis phase. The expression of proliferating cell nuclear antigen was significantly enhanced with the increase in dose with the test substance. It is suggested that the induction of abnormal cell proliferation may be one of the causes of the carcinogenic effects of these three non-genotoxic carcinogens.