Function association of enhanced expressed genes between Opisthorchis viverrini and non Opisthorchis viverrini-related cholangiocarcinoma.

Palabras clave: Opisthorchis viverrini. Colangiocarcinoma. Cholangiocarcinoma is one of the serious malignancies. It is a type of primary hepatobiliary tumor, there is a wide spectrum of tumors of varying differentiation and malignancy grades (1,2). It is the second most common primary cancer in the liver, and its incidence is highest in the northeastern part of Thailand (3). The etiology of this cancer is very complex. One of the most widely mentioned underlying cause for cholangiocarcinoma is chronic Opisthorchis viverrini infection (4,5). However, a number of cholangiocarcinoma without chronic Opisthorchis viverrini infection can be seen (4,5). Although it has been determined for a long time, there is limited knowledge on the gene expression and biomarkers for this cancer (1,2). Systemic approach on the ge-nomics and proteomics might provide useful information to better understand the gene expression and biomarker of cholangio-carcinoma. According to a recent study by Jinawath et al., the putative signature of Opisthorchis viverrini-related cholangiocar-cinoma exhibited elevated expression of genes involved in xeno-biotic metabolism (UGT2B11, UGT1A10, CHST4, SULT1C1), whereas that of non-Opisthorchis viverrini-related cholangiocar-cinoma represented enhanced expression of genes related to growth factor signaling (TGFBI, PGF, IGFBP1, IGFBP3) (3). These data might serve as a starting point for the identification of novel diagnostic markers or therapeutic targets for the disease (3). In this work, function association of enhanced expressed genes between Opisthorchis viverrini and non Opisthorchis viverrini-related cholangiocarcinoma was studied. The author used gene ontology technique to perform this work. The functional association study was performed. The tool namely FuncAssociate was used. FuncAssociate is a web-based tool to help researchers use gene ontology attributes to characterize large sets of genes derived from experiment (6). The focused studied genes are UGT2B11, UGT1A10, CHST4, SULT1C1, TGFBI, PGF, IGFBP1, and IGFBP3 because these genes were reported to overexpress in cholangiocarcinoma (3). The condition was set for human cholangiocarcinoma. To test the functional association, the algorithm makes use of single hypothesis one-sided p-value of the association between attribute and query (based on Fisher's exact test) and p value was accepted as a statistical significant level at p value equal to or less than 0.05 (6). According to this work, there is neither overrepresented nor underrepresented attribution for single set of genes in separated Opisthorchis viverrini (UGT2B11, UGT1A10, CHST4, SULT1C1) and non Opisthorchis viverrini-related cholangiocarcinoma (TGFBI, PGF, IGFBP1, IGFBP3). Nevertheless, there is overrepresented attribution for the whole set of genes (UGT2B11, UGT1A10, CHST4, SULT1C1, TGFBI, …