Salmonella is the leading cause of illness among all food-borne diseases annually. One of the reasons salmonella, a bacteria, is so potent is its ability to penetrate cell barriers and replicate inside hosts. Now scientists have discovered a way to use salmonella's super power for the good of mankind, by creating a non-toxic strain of the bacteria to target and penetrate prostate cancer cells.

"Salmonella strains have a natural preference for infiltrating and replicating within the cancer cells of a tumor, making the bacteria an ideal candidate for bacteriotherapy," said Robert Kazmierczak, a senior investigator at the Cancer Research Center and a post-doctoral fellow in Division of Biological Sciences in the Inovesity of Missouri's College of Arts and Science. "Bacteriotherapy is the use of live bacteria as therapy to treat a medical condition, like cancer."

The good-guy strain of salmonella had been christened CCRC2631, and is designed to render the bacteria nontoxic and enhance its natural ability to target and kill cancer cells without harming normal, healthy cells. So far, the new Salmonella strain has just been tested on mice with prostate cancer.

"We found that the mice tolerated the treatment well and when examined, their prostate tumors decreased by about 20 percent compared to the control group," Kazmierczak said. "One of the most remarkable aspects of Salmonella is its ability to target, spread and persist inside the tumor. We are taking advantage of this ability by using Salmonella to carry or generate effective chemotherapeutic drugs, concentrating them at and throughout the tumor. The goal of this treatment is to develop a bacterial vector that can destroy the tumor from the inside out and reduce the amount of side effects endured by patients with cancer."

But this new strain of Salmonella is not one that scientists can just whip up in a lab on any given Tuesday. CCRC2631 is derived from Salmonella that was stored in a test tube at room temperature for more than 50 years. The sample originates from a collection of mutant strains of Salmonella collected by an MU geneticist. The collection contains over 20,000 different samples of Salmonella, with half of the samples housed at the Cancer Research Center where researchers affiliated with MU focus on three areas of cancer research: early detection, targeted treatment and new, effective chemotherapy.

The research has been published in the journal PLOSone.