Are stem cells the link between bacteria and cancer?
While it has long been recognized that certain viruses can cause cancer by inserting oncogenes into the host cell DNA, the fact that some bacteria can also cause cancer has been slower to emerge and much harder to prove. While it is now clear that most cases of stomach cancer are linked to chronic infections with H. pylori , the mechanism remains unknown. Thomas F. Meyer and his colleagues at the Max Planck Institute for Infection Biology in Berlin have spent many years investigating this bacterium and the changes it induces in the cells of the stomach epithelium. In particular, they were puzzled how malignancy could be induced in an environment in which cells are rapidly replaced. They suspected that the answer might lie in the stem cells found at the bottom of the glands that line the inside of the stomach, which continually replace the remaining cells 'from the bottom up' -- and which are the only long-lived cells in the stomach . Michael Sigal, a clinical scientist