A new discovery may have brought the use of Salmonella to fight bowel cancer one step closer.
Cancer Research UK-funded researchers in Glasgow and Birmingham have pinpointed the mechanism that suppresses the immune system in bacterial treatments and proposed a solution.
Previous research has looked at using bacteria, including Salmonella, to combat cancer due to their ability to suppress tumour cell growth.
However, they also suppress a part of our immune system essential for fighting tumours, limiting their success.
The new study, published in the journal EMBO Molecular Medicine, examined the response of T cells to a specially engineered safe form of Salmonella in mice with colorectal cancer.
Researchers found that the Salmonella prevents the T cells, key immune cells that protect the body from infections and cancer, from stopping the colorectal cancer cells.
The bacteria deplete an amino acid called asparagine, which suppresses tumour growth but also disrupts the metabolic processes of T cells.
Researchers believe that by engineering Salmonella bacteria not to attack asparagine, T cells will be able to attack cancer cells alongside the bacteria.
Dr Kendle Maslowski, lead researcher from the Cancer Research UK Scotland Institute and the University of Glasgow, said: “We know attenuated Salmonella and other bacteria have the power to tackle cancer, however until now it was not known why it was not proving as effective as it should be.
“Our research has discovered that it is an amino acid called asparagine that the bacteria attacks which is essential for T cells to be activated.
“We believe this knowledge could enable bacteria to be engineered not to attack asparagine allowing the T cells to act against the tumour cells leading to new effective treatments for cancer.”
Further research will now be undertaken to use this key discovery to develop future ways of harnessing the power of bacteria in cancer treatment.