Bacteria commonly used in probiotic yoghurts have been shown to be a safe and effective way to deliver gene therapies to treat cancer, according to scientists based at Ireland's University College Cork (UCC).

The research team found that bifidobacteria were able to travel through the body and grow inside tumours, where they could disseminate treatments to kill off cancer cells. Mark Tangney, principal investigator at the UCC's Cork Cancer Research Centre, said: "When a patient's cancer has spread, then ideally a treatment should be administered throughout a patient's body to allow treatment of any tumours present. However, current chemotherapy drugs administered in this fashion are toxic to many healthy cell types, often resulting in severe side effects for the patient.

"This is why we are so excited about this research. We have shown that harmless bacteria have a natural ability to travel through the body and grow specifically inside tumours. We have demonstrated for the first time that following ingestion of bifidobacteria in large numbers, these bacteria can leak out from the gut into the blood and grow inside tumours throughout the body where they can produce whatever we want. We can now genetically engineer these bacteria so that they will pump out anti-cancer agents specifically inside tumours. These new results suggest we can overcome a major barrier to achieving an efficient and safe gene medicine for cancer."

The findings from the study have been published in the scientific journal Molecular Therapy. The next stage in the development of the treatment will be a Phase 1 clinical trial, Tangney said.

Noriyuki Kasahara, president of the International Society for Cell & Gene Therapy of Cancer said: "The work being done at the Cork Cancer Research Centre is certainly at the cutting edge of science. No one has ever shown before that you can take an orally administered safe bacteria and have it hone into a tumour mass before and act there."