A comparative analysis of gene expression profile in liver and esophagus cancer by expressed sequence tags

Liver and esophagus cancers are widely spread in Iranian population. This study aims to explore the common up-regulated genes in liver and esophagus tumor tissues by expressed sequence tags (ESTs) and to identify the role of key genes in cancer development. EST profiles of protein-coding genes in two different cancer types and their normal tissues were extracted from UniGene database. All data (17242 genes) were categorized into 5 cut-off and the maximum rank was selected (> 1500 TPM). The ratio of cancer to normal of up-regulated genes was then measured which limited to more than one times. The common genes between liver and esophagus cancers further recognized. Finally, functional and pathway analysis was performed on genes by bioinformatics databases. Among total genes were screened out, in which 54 and 27 over expressed genes were identified in liver and esophagus cancers, respectively. These cancer tissues shared nine up-regulated genes that involved in cell cycle through G2/M checkpoint, G1/S transition and DNA replication. Likewise, they participate in VEGF, HIF-1, estrogen signal pathways and Toll like receptor cascade. Similar up-regulated genes and underlying molecular mechanisms implicated in both cancers could be valuable targets in diagnosis and treatment area of cancer therapy.

Keywords:

Liver cancer , Esophagus cancer , ESTs , Up-regulated genes , Molecular mechanism