The researchers had previously developed a tumor-targeting, genetically-altered strain of Salmonella -- the same bacterium that, in its unaltered or wild type form, can cause food poisoning and septic shock. It was shown to be safe in animal studies, significantly prolonging the lives of mice by suppressing tumor growth. The genetically altered bacteria are currently being tested in Phase I clinical trials with human cancer patients.

"For a number of reasons, we thought that combining these Salmonella with X-ray treatments might be a good strategy for improved therapy," noted John Pawelek, M.D., senior research scientist at the Yale University School of Medicine. "It was exciting to see the positive results."

In a typical experiment, tumor suppression by a combination of X-rays and Salmonella was greater than that seen with either X-rays or Salmonella alone. In fact, the effects of the combination were greater than what would have been expected by the simple addition of the effects of either treatment alone. These results were seen against two different types of melanoma, as well as in colon and breast cancers.

"It appears that the combination of genetically engineered Salmonella with radiotherapy could be a new and beneficial treatment for solid tumors," said Pawelek. "Because of the large number of cancer patients who receive radiation therapy, the potential impact of this finding is tremendous."

Collaborating with Pawelek at Yale were Sara Rockwell, Ph.D. and K. Brooks Low, Ph.D. along with David Bermudes, Ph.D. of Vion Pharmaceuticals.

Note: If no author is given, the source is cited instead.

• Breast Cancer
• Cancer
• Colon Cancer
• Brain Tumor
• Foodborne Illness
• Skin Cancer

• Metastasis
• Salmonella infection
• Tumor suppressor gene
• Tumor
• Heat shock protein
• Hormone replacement therapy