Salmonella Slows Tumor Growth in Some Cancers
Salmonella typhimurium decreases tumor growth in murine breast and colon cancers
WEDNESDAY, July 30 (HealthDay News) -- Salmonella typhimurium inhibits the growth of breast and colon tumors and decreases pulmonary metastasis in breast cancer models without inducing severe toxicity, according to a study published online July 29 in the Journal of the National Cancer Institute .
Markus Loeffler, M.D., of the Burnham Institute for Medical Research in La Jolla, Calif., and colleagues administered specially engineered Salmonella typhimurium designed to express the Fas ligand (FasL) or phosphate-buffered saline into immunocompetent mice carrying murine D2F2 breast carcinoma or CT-26 colon carcinoma cells.
Tumor growth was inhibited by treatment with FasL-expressing Salmonella typhimurium by an average of 59 percent for the murine breast cancer tumors and 82 percent for the murine colon cancer tumors. Pulmonary metastases in murine breast cancer were reduced by 34 percent in the Salmonella typhimurium FasL-treated mice compared with phosphate-buffered saline-treated mice. Administration of Salmonella typhimurium was not associated with overt toxicity.
"We have demonstrated that systemic delivery of attenuated S. typhimurium expressing a soluble version of FasL reduces growth of primary tumors and pulmonary metastases in mouse cancer models using multidrug-resistant murine tumors in immunocompetent animals," the authors write. " These results from murine cancer models suggest that FasL- expressing S. typhimurium could offer an acceptable strategy for employing FasL and possibly other toxic cytokines for cancer therapy."