Discovery of stage-related proteins in esophageal squamous cell carcinoma using proteomic analysis

Esophageal squamous cell carcinoma (ESCC) is the major subtype of esophageal cancers in China, and characterized with high morbidity and mortality. So far, the diagnosis of ESCC is mainly dependent on the alterations in esophageal histology, but most cases of ESCC with low stage do not display visible histological abnormalities. Therefore, a deep understanding of the mechanism of ESCC progression and seeking stage-specific molecules might improve the diagnosis and therapy for ESCC. In this study, we used proteomics to analyze ESCC tissues with classification by TNM stage, and determined the proteomic features correlated with ESCC progression (from stages I to III). Proteins that exhibited significantly different expression patterns between ESCC and corresponding normal esophageal tissues were identified using MS. The identified proteins with differentiated expression mainly fell into three protein categories (i.e. cytoskeleton system-associated proteins, metabolism enzymes, and heat shock proteins). In addition, real-time PCR highlighted some molecules that were associated with tumor stages at the mRNA level, such as enolase 1, chromosome 1 ORF 10, elastase inhibitor, α B crystalline, stress-induced phosphoprotein 1, and squamous cell carcinoma antigen 1. Altogether, these data provided further information on ESCC progression and potential drug targets for ESCC clinical therapy.