New York, Oct 30 (IANS): US scientists have developed a non-toxic strain of Salmonella to penetrate and target cancer cells which may lead to promising new treatments that actively target and control the spread of cancer.

Salmonella -- bacterium that causes food borne diseases -- has a unique characteristic that allows the bacteria to penetrate through cell barriers and replicate inside its host.

"Salmonella strains have a natural preference for infiltrating and replicating within the cancer cells of a tumour, making the bacteria an ideal candidate for bacteriotherapy," said Robert Kazmierczak, post-doctoral fellow at the University of Missouri, the US.

Bacteriotherapy is the use of live bacteria as therapy to treat a medical condition, like cancer.

For the study, the team developed CRC2631 -- a Salmonella strain derived from a Salmonella sample that was stored in a test tube at room temperature for more than 50 years.

The Salmonella strain was genetically modified to render the bacteria non-toxic and enhance its natural ability to target and kill cancer cells -- without harming normal, healthy cells and was then administered directly into the circulatory system of mice with prostate cancer.

"We found that the mice tolerated the treatment well and when examined, their prostate tumours decreased by about 20 per cent 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 tumour. We are taking advantage of this ability by using Salmonella to carry or generate effective chemotherapeutic drugs, concentrating them at and throughout the tumour," he added.

Kazmierczak said the goal of this treatment is to develop a bacterial vector that can destroy the tumour from the inside out and reduce the amount of side effects endured by patients with cancer.

The study was published in the journal PLOS ONE.