

A possible link between cancer and toxins or poisons produced by bacteria has been suggested by King’s College London scientists, the Society for General Microbiology’s meeting in Bath will hear next week, Thursday 01 April 2004.
“As the molecular mechanisms of cancer are becoming better understood, the strong association between Helicobacter pylori and a stomach cancer, gastric adenocarcinoma, has shown that some cancers may start from bacterial infections”, says Professor Alistair Lax of the Department of Microbiology at the Dental Institute, King’s College London. “Recently other bacterial infections have also demonstrated a greater likelihood that a patient will develop cancer. The link has been controversial for a long time, but we can now show one way that it may work”.
Many poisons produced by bacteria are known to act inside our cells, chemically changing some of the processes that govern communication within a cell, and the normal rhythm of cell life is disrupted. This communication process determines whether a cell will grow and divide, or die. Some of the crucial cell proteins are mutated or disrupted during the switch to become a cancer cell, and the scientists think that some bacterial poisons could directly promote cancer formation.
“In particular the bacterium Pasteurella multocida produces a poison which stimulates several of these communication pathways which we know are characteristic of cell changes seen in cancers”, says Prof Lax.
The research presented today is the result of over ten years’ work on bacterial toxins, and the scientists stress that more information is needed about how these toxins work, and in particular which components of our cells they directly affect. The hypothesis that such toxins can cause cancer or make cancer more likely needs further experimental testing. If further work confirms the hypothesis, doctors and medical researchers will then be able to develop better treatment and preventative measures for some cancers.