Analysis of gene expression in esophageal squamous cell carcinoma (ESCC)

To characterize gene expression in esophageal squamous cell carcinoma, we examined gene expression in tumor and matched normal adjacent tissue from 17 ESCC patients from a high-risk region of China. RNA was extracted from 17 micro-dissected tumor and matched normal tissue pairs using the PureLink Micro-to-Midi Total RNA Purification System (Invitrogen, Carlsbad, CA) Affymetrix HG-U133A 2.0 gene expression arrays were performed according to the manufacturer's directions. The Robust Multiarray Average (RMA) algorithm implemented in Bioconductor in R was used for background correction and normalization across all samples.