Ewingella americana attacked the tumours directly while also stimulating the immune system, producing a 100 percent response rate. Scientists say the findings offer encouraging proof of concept for developing naturally occurring bacterial cancer therapies.

Credits: Unsplash; Author: Zdeněk Macháček;

The bacterium multiplied inside oxygen-deprived tumour tissue, accumulated mainly within the cancer and did not colonise healthy organs. It was also cleared quickly from the bloodstream without signs of infection. Researchers now hope to test whether the approach could work against other solid tumours, including breast cancer, pancreatic cancer and melanoma, although results remain limited to mice.