del Senno L, Barbieri R, Amelotti F, Bernardi F, Buzzoni D, Marchetti G, Patracchini P, Piva R, Rossi M, Conconi F
Cancer Detect Prev. 1986;9(1-2):9-15.
The correlation between expression and extent of DNA methylation of c-myc and c-abl oncogenes has been investigated in the human leukemic K-562 cell line before and after 5-azacytidine-mediated erythroid induction. RNA accumulation was analyzed by cytoplasmic dot hybridization and DNA methylation by using HpaII and MspI endonucleases, which differently cleave the CCGG sequence depending on cytosine methylation. Both the oncogenes are expressed in uninduced cells; however, whereas the c-myc expression does not change following 5-azacytidine treatment, the c-abl expression sharply decreases. The HpaII pattern shows that the c-myc DNA region is undermethylated and that the c-abl gene is hypermethylated both before and after the erythroid induction. Nevertheless, in both the genes 5-azacytidine produces variations in the MspI pattern compatible with mCmCGG to CmCGG demethylations.
在5-氮杂胞苷介导的红系诱导前后，对人白血病K-562细胞系中c-myc和c-abl癌基因的表达与DNA甲基化程度之间的相关性进行了研究。通过细胞质斑点杂交分析RNA积累情况，并使用HpaII和MspI核酸内切酶分析DNA甲基化情况，这两种酶根据胞嘧啶甲基化情况对CCGG序列进行不同的切割。两种癌基因在未诱导的细胞中均有表达；然而，5-氮杂胞苷处理后，c-myc的表达没有变化，而c-abl的表达急剧下降。HpaII图谱显示，在红系诱导前后，c-myc基因区域的DNA甲基化程度均较低，而c-abl基因的甲基化程度较高。尽管如此，5-氮杂胞苷在这两个基因中均产生了与mCmCGG至CmCGG去甲基化相符的MspI图谱变化。
