交链孢酚（AOH）处理人胎食管上皮组织c－myc癌基因，Rb抗癌基因扩增的研究

Study of the c-myc and Rb gene amplification in human fetal esophageal epithelium treated by altenariol

用ＡＯＨ对人胎食管上皮组织体外处理不同时间（２４ｈ，ｌｗｔ和３ｗｋ），提取该组织高分子量的ＤＮＡ，从１０例食管癌组织以及１０例癌旁组织手术标本分别提取ＤＮＡ，提取正常人胎儿食管上皮ＤＮＡ做对照。用ＥｃｏＲＩ酶切，Ｓｏｕｔｈｅｍ转移，与ｃ－ｍｙｃ癌基因，Ｒｂ抗癌基因探针杂交。结果显示：ＡＯＨ诱导ｌｗｋ的人胎儿食管上皮中即有ｃ－ｍｙｃ癌基因的扩增，并持续到第３ｗｋ，而ＡｏＨ诱导２４ｈ，ｌｗｋ和３ｗｋ的人胎儿食管上皮中均未发现抗癌基因Ｒｂ的丢失。表明：ＡｏＨ激活了ｃ－ｍｙｃ癌基因。这种改变可能对启动细胞的增殖有一定的促进作用，Ｒｂ抗癌基因的丢失在食管癌发生中可能是一种较晚期的变化。

High-molecular- weight DNA was extracted from the human fetal esophagus(HFE)induced by alternariol (AOH)in vitro at different times(24hours,l weeks).Ascontrols,DNA from normal HFE,and DNA from esophageal cancer tissueS and tissues adjacent tothe tumour of 10 cases were extracted separately。These DNA samples were also diges ted withEcoRI enzyme and subjected to Southern blotting,and hybridized with c-myc gene and Rb geneprobe. The result showed that there was amplification of c-myc gene in HFE indueed by AOH in1 week,and that the amplification continued to the third week.There were not any deletion of Rbgene detected in HFE treated with AOH in vitro for 24 hours to 3 weeks.These results suggested thatc-myc was activated by AOH. The activation of c-myc gene was probably the initiating event inesophageal carcinogenesis induced by AOH. And that the inactivation of Rb anti-oncogene mightbe involved as a late event in esophageal carcinogenesis.