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为探讨杂色曲霉素（ＳＴ）的致癌作用，运用细胞培养、流式细胞术（ｆｌｏｗｃｙｔｏｍｅｔｒｙ，ＦＣＭ）和银染ＰＣＲ－ＳＳＣＰ等方法研究了不同浓度的ＳＴ（１ｍｇ／Ｌ和３ｍｇ／Ｌ）诱发体外培养的人胚胃粘膜细胞恶性转化情况以及此过程中抑癌基因ｐ５３在蛋白及基因水平上的变化。结果表明，ＳＴ处理４周后处理细胞增殖旺盛，并出现恶性转化灶；ＳＴ处理２４周后处理细胞可在软琼脂上形成细胞集落（ＳＴ１ｍｇ／Ｌ和３ｍｇ／Ｌ组每皿细胞集落数平均分别为１５和１７个）；ＦＣＭ检测结果表明，ＳＴ处理的细胞细胞增殖指数增高，ＤＮＡ含量增高，出现ＤＮＡ异倍体，突变型抑癌基因ｐ５３蛋白表达明显增强。ＰＣＲ－ＳＳＣＰ分析结果显示，ＳＴ处理２２周后，处理细胞ｐ５３第８外显子出现异常泳动带型。本研究进一步证实了ＳＴ对体外培养的人胚胃粘膜细胞的致癌作用
To investigate the carcinogenic effects of sterigmatocystin (ST), different concentrations of ST (1 mg/L and 3 mg/L) were studied by cell culture, flow cytometry (FCM) and silver staining PCR-SSCP. Induced malignant transformation of human embryonic-gastric mucosal cells in vitro and changes in the protein and gene levels of tumor suppressor gene p53 during this process. The results showed that after 4 weeks of ST treatment, the proliferation of the treated cells was prosperous and the malignant transformation foci appeared; after 24 weeks of ST treatment, the treated cells could form colonies on soft agar (the average number of colony cells per dish in the ST1 mg/L and 3 mg/L groups, respectively 15 and 17); FCM test results showed that the cell proliferation index of ST-treated cells increased, DNA content increased, DNA aneuploidy appeared, and the expression of mutant tumor suppressor gene p53 protein was significantly enhanced. The results of PCR-SSCP analysis showed that after 22 weeks of ST treatment, the exocytosis pattern of exon 8 of p53 was abnormal in the treated cells. This study further confirmed the carcinogenic effect of ST on cultured human embryonic gastric mucosa cells.