Recent reports suggest that the East Asian liver fluke infection, caused by Opisthorchis viverrini, which is implicated in opisthorchiasis-associated cholangiocarcinoma, serves as a reservoir of Helicobacter pylori. The opisthorchiasis-affected cholangiocytes that line the intrahepatic biliary tract are considered to be the cell of origin of this malignancy. Here, we investigated interactions in vitro among human cholangiocytes, Helicobacter pylori strain NCTC 11637, and the congeneric bacillus, Helicobacter bilis. Exposure to increasing numbers of H. pylori at 0, 1, 10, 100 bacilli per cholangiocyte of the H69 cell line induced phenotypic changes including the profusion of thread-like filopodia and a loss of cell-cell contact, in a dose-dependent fashion. In parallel, following exposure to H. pylori, changes were evident in levels of mRNA expression of epithelial to mesenchymal transition (EMT)-encoding factors including snail, slug, vimentin, matrix metalloprotease, zinc finger E-box-binding homeobox, and the cancer stem cell marker CD44. Analysis to quantify cellular proliferation, migration, and invasion in real-time by both H69 cholangiocytes and CC-LP-1 line of cholangiocarcinoma cells using the xCELLigence approach and Matrigel matrix revealed that exposure to ≥10 H. pylori bacilli per cell stimulated migration and invasion by the cholangiocytes. In addition, 10 bacilli of H. pylori stimulated contact-independent colony establishment in soft agar. These findings support the hypothesis that infection by H.pylori contributes to the malignant transformation of the biliary epithelium.

Recent reports suggest that the East Asian liver fluke Opisthorchis viverrini, which is implicated in pathogenesis of opisthorchiasis-associated cholangiocarcinoma, serves as a reservoir of Helicobacter pylori. The affected cholangiocytes that line the intrahepatic biliary tract are considered to be the cell of origin of this malignancy. Here, we investigated interactions among a human cholangiocyte cell line, H69, a CCA cell line CC-LP-1, CagA+ve Helicobacter pylori, and H. bilis bacilli. Exposure to increasing numbers of H. pylori at 0, 1, 10,100 bacteria per cholangiocyte cell induced phenotypic changes in the cultured cholangiocytes including profusion of thread-like filopodia and loss of cell-cell contact in a dose-dependent fashion. In parallel, changes in mRNA expression followed exposure to H. pylori, with increased expression of epithelial to mesenchymal transition (EMT) associated-factors including snail, slug, vimentin, matrix metalloprotease, zinc finger E-box-binding homeobox, and the cancer stem cell marker CD44. Transcription levels encoding the cell adhesion marker CD24 decreased. Analysis in real time using the xCELLigence system to quantify cell proliferation, migration and invasion revealed that exposure to ten to 50 of H. pylori stimulated migration of H69 cells and CC-LP-1 cells, a line derived form of a human cholangiocarcinoma, and invasion through an extracellular matrix. In addition, ten bacilli of CagA+ve H. pylori stimulated contact-independent colony establishment in soft agar. These findings support the hypothesis that infection with H. pylori can contribute to the malignant transformation of the biliary epithelium.

Recent reports implicate both the liver fluke Opisthorchis viverrini as a reservoir of Helicobacter pylori within the human gastrointestinal tract and H. pylori in the pathogenesis of opisthorchiasis-associated cholangiocarcinoma. We postulated that adherence of bacterial ligands to host receptors initiates colonization of the live fluke by H. pylori and here we aimed to assess the molecular interaction between O. viverrini and H. pylori by investigating host receptors for H. pylori in the fluke. Several known receptors of H. pylori including Lewis B, sialyl-Lewis X, Toll-like receptor 4 and L-fucose were detected immunohistochemically and histochemically by focusing analysis on the gut epithelium and tegument of the adult stage of the fluke. The frequency of detection of Lewis B, sialyl-Lewis X, TLR4 and L-fucose in 100 individual worms was 3, 3, 19 and 70%, respectively. Detection of H. pylori by a diagnostic ureA gene-based PCR assay revealed the presence of H. pylori in individual O. viverrini worms in 41 of 49 (79%) worms examined. In addition, numbers of bacteria decreased in a dose- and time-dependent fashion following exposure to fucosidase. These findings suggested that L-fucose represents a tractable receptor for H. pylori that can mediate bacterial colonization of the gut of O. viverrini.