Abstract
Abstract
Gastric and enteric Helicobacter species have been associated with malignant and inflammatory diseases of the stomach, liver, gall bladder and intestine. Matrix metalloproteinases (MMPs) participate in degradation of extracellular matrix, which allows bacteria to come in contact with and interact with the cells. Enhanced level of MMPs facilitates metastasis and cell invasion of tumor cells by removal of physical barriers, as well as modulation of biologic activities of the proteins residing in the extracellular matrix. The aim of this study was to evaluate the effect of gastric and enteric Helicobacter on induction of MMPs in hepatocytes and epithelial cells of gall bladder and colon. Human hepatocytes HepG2, gall bladder epithelial cells TFK-1, and colon epithelial cells HT29 were infected with strains of H. pylori cagA+, cagE+, H. pylori cagA-, cagE−, H. pullorum, H. cholecystus, H. bilis and H. hepaticus. Protein levels of MMPs were analyzed by enzyme-linked immunosorbent assay and immunohistochemistry. Reverse transcription-quantitative polymerase chain reaction was used to study mRNA levels. Increased expression of MMP-2 and MMP-9 was observed on HepG2, TFK-1 and HT29 infected with H. pylori cagA+, cagE+ and H. cholecystus strains. H. pylori cagA+, cagE+, H. cholecystus, H. pullorum, H. bilis and H. hepaticus strains increased expression of MMP-7 on HT29, compared to uninfected control cells. The effect of MMP upregulation on HepG2, TFK-1 and HT29 was bacterial dose dependent. H. pylori cagA−, cagE− strain did not increase expression of MMPs. Inducible MMPs on colon and bile duct epithelial cells as well as hepatocytes may play an important role in facilitating invasion and progression of cancer by Helicobacter species colonizing the hepatobiliary and gastrointestinal tract.