Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jun 14, 2006; 12(22): 3585-3592
Published online Jun 14, 2006. doi: 10.3748/wjg.v12.i22.3585
Gene expression profiling defined pathways correlated with fibroblast cell proliferation induced by Opisthorchis viverrini excretory/secretory product
Chanitra Thuwajit, Peti Thuwajit, Kazuhiko Uchida, Daoyot Daorueang, Sasithorn Kaewkes, Sopit Wongkham, Masanao Miwa
Chanitra Thuwajit, Peti Thuwajit, Daoyot Daorueang, Sopit Wongkham, Department of Biochemistry, Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
Sasithorn Kaewkes, Department of Parasitology, Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
Kazuhiko Uchida, Masanao Miwa, Institute of Basic Medical Science, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
Co-first authors: Peti Thuwajit
Supported by the Thailand Research Fund, Grant No. TRG4880004 and the Grants of Khon Kaen University 2004 and 2006; Grants-in-Aid for Scientific Research from the Ministry of Education, Science, Sports and Culture of Japan; the Grant for Student of Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, 2003-2005
Correspondence to: Chanitra Thuwajit, PhD, MD, Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. tchani@kku.ac.th
Telephone: +66-43-348386 Fax: +66-43-348386
Received: February 1, 2006
Revised: February 25, 2006
Accepted: March 1, 2006
Published online: June 14, 2006
Abstract

AIM: To investigate the mechanism of fibroblast cell proliferation stimulated by the Opisthorchis viverrini excretory/secretory (ES) product.

METHODS: NIH-3T3, mouse fibroblast cells were treated with O. viverrini ES product by non-contact co-cultured with the adult parasites. Total RNA from NIH-3T3 treated and untreated with O. viverrini was extracted, reverse transcribed and hybridized with the mouse 15K complementary DNA (cDNA) array. The result was analyzed by ArrayVision version 5 and GeneSpring version 5 softwares. After normalization, the ratios of gene expression of parasite treated to untreated NIH-3T3 cells of 2-and more-fold upregulated was defined as the differentially expressed genes. The expression levels of the signal transduction genes were validated by semi-quantitative SYBR-based real-time RT-PCR.

RESULTS: Among a total of 15 000 genes/ESTs, 239 genes with established cell proliferation-related function were 2 fold-and more-up-regulated by O. viverrini ES product compared to those in cells without exposure to the parasitic product. These genes were classified into groups including energy and metabolism, signal transduction, protein synthesis and translation, matrix and structural protein, transcription control, cell cycle and DNA replication. Moreover, the expressions of serine-threonine kinase receptor, receptor tyrosine kinase and collagen production-related genes were up-regulated by O. viverrini ES product. The expression level of signal transduction genes; pkC, pdgfrα, jak 1, eps 8, tgfβ 1i4, strap and h ras measured by real-time RT-PCR confirmed their expression levels to those obtained from cDNA array. However, only the up-regulated expression of pkC, eps 8 and tgfβ 1i4 which are the downstream signaling molecules of either epidermal growth factor (EGF) or transforming growth factor-β (TGF-β) showed statistical significance (P < 0.05).

CONCLUSION: O. viverrini ES product stimulates the significant changes of gene expression in several functional categories and these mainly include transcripts related to cell proliferation. The TGF-β and EGF signal transduction pathways are indicated as the possible pathways of O. viverrini-driven cell proliferation.

Keywords: Gene expression profile; Opisthorchis vi-verrini; Excretory/secretory product; cDNA array; Fibroblast; Cell proliferation; Signal transduction; Cholangiocarcinogenesis