Expression data from human Esophageal squamous cell carcinoma (ESCC). Homo sapiens

Downregulation is a common feature of tumor suppressor gene (TSG), which can be caused by allele deletion, promoter hypermethylation, histone deacetylation and posttranscriptional silencing by microRNA. Therefore, comparison of expression profiles by cDNA microarray between tumor and non-tumor tissues and characterization of downregulated genes in tumor specimens is a useful strategy to identify TSGs. To identify deregulated genes during ESCC development, Affemetrix cDNA microarray was applied to compare differentially expressed genes between 4 pairs of ESCC tumors and corresponding adjacent non-tumor tissues (#301, #327, #351 and #363), and one pair of esophageal dysplasia tissue and adjacent normal tissue (#314). Overall design: Clinical specimens were collected from patients with ESCCs who underwent surgical resection of tumor tissues. Paired adjacent nontumor tissues from the proximal resection margins (>5 cm away from the ESCC sample) were also collected for RNA extraction and hybridization on affymetrix microarrays.

肿瘤抑制基因（tumor suppressor gene, TSG）的表达下调是其常见特征，该下调可由等位基因缺失、启动子高甲基化、组蛋白去乙酰化以及microRNA介导的转录后沉默所引发。因此，通过cDNA微阵列（cDNA microarray）比较肿瘤与非肿瘤组织的表达谱，并对肿瘤标本中的下调基因进行特征分析，是鉴定肿瘤抑制基因的有效策略。为鉴定食管鳞状细胞癌（esophageal squamous cell carcinoma, ESCC）发生过程中的失调基因，本研究采用Affemetrix cDNA微阵列，对4对食管鳞状细胞癌肿瘤组织与对应癌旁非肿瘤组织（编号#301、#327、#351、#363）以及1对食管异型增生组织与邻近正常组织（编号#314）之间的差异表达基因进行了比较分析。实验整体设计如下：临床标本取自接受肿瘤组织手术切除的食管鳞状细胞癌患者，同时采集来自近端切缘（距肿瘤样本>5cm）的配对癌旁非肿瘤组织，用于RNA提取及Affymetrix微阵列杂交。