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背景 GATA转录因子家族在胚胎发育时期能够促进胃肠道的正常发育,并有助于在成年肠上皮的不断更新中调节组织分化,最近有报道在人胃肠肿瘤中GATA基因,即GATA-4,GATA-5的表达缺失。目的 探讨在食管肿瘤中渐进性的转录沉默而导致GATA相关基因表达缺失的情况。方法 用RT-PCR法检测GATA-4,-5,-6基因在17个食管鳞癌细胞系中的表达,从每个细胞系及88例原发性食管肿瘤标本中提取DNA,进行甲基化特异性PCR(methylation-specific PCR,MSP),以检测GATA相关基因增强子区的甲基化情况,用5-aza-2’-deoxycytidine c5-aza-dc)在去甲基化的细胞系中进行检测GATA-4,-5基因的表达与增强子甲基化之间的关系,并对GATA增强子区进行亚硫酸氢盐测序以证实MSP的结果。结果 GATA-4/-5的表达在大多数食管癌细胞系中缺失,在每个未检测到GATA基因表达的细胞系中均可发现转录起始下游包括CpG岛在内的异常甲基化,GATA-6在每一细胞系中均表达。在正常食管粘膜中未发现GATA-4/-5增强子的甲基化,而GATA-4/-5的甲基化却可以在原发性食管癌中检测到。在27/44(61%)的食管鳞癌和31/44(71％)的食管腺癌中,发现GATA-4的甲基化,与此类似,GATA-5的甲基化也在一部分食管肿瘤中被检测到。结论 本文是关于继发于基因增强子高甲基化的食管肿瘤中,GATA-
Background GATA family of transcription factors during embryonic development can promote the normal development of the gastrointestinal tract and contribute to the regulation of tissue differentiation in the continuous renewal of adult intestinal epithelium. Recently, it has been reported that GATA gene in human gastrointestinal tumors, GATA-4 , GATA-5 expression is missing. Objective To investigate the loss of GATA-related gene expression induced by progressive transcriptional silencing in esophageal neoplasms. Methods The expression of GATA-4, -5, -6 gene in 17 esophageal squamous cell carcinoma cell lines was detected by RT-PCR. DNA was extracted from each cell line and 88 primary esophageal tumor samples. Methyl Methylation-specific PCR (MSP) was performed to detect the methylation status of the GATA-related gene enhancer region, and the demethylation of cell lines was performed using 5-aza-2’-deoxycytidine c5-aza- The relationship between GATA-4, -5 gene expression and enhancer methylation was examined, and bisulfite sequencing of the GATA enhancer region was performed to confirm the results of MSP. Results The expression of GATA-4 / -5 was absent in most esophageal cancer cell lines. Aberrant methylation, including CpG islands, downstream of transcriptional initiation was found in every cell line in which no GATA gene expression was detected, GATA-6 is expressed in every cell line. No methylation of the GATA-4 / -5 enhancer was found in normal esophageal mucosa, whereas methylation of GATA-4 / -5 was detectable in primary esophageal cancer. Methylation of GATA-4 was found in 27/44 (61%) of esophageal squamous carcinomas and 31/44 (71%) of esophageal adenocarcinomas, and similarly, methylation of GATA-5 was also found in part of the esophagus Tumor was detected. Conclusion This article is about esophageal cancer secondary to genetic enhancer hypermethylation, GATA-