A substance found in pomegranates can boost immune cells that help fight cancer, according to a new study. Scientists studying therapies for colon cancer discovered that a metabolite in pomegranate, known as urolithin A, rejuvenates immune T cells which are then better at fighting tumours.
Colon, or colorectal cancer, remains a disease with high mortality rates in advanced stages. Early diagnosis and therapy have improved in recent years but not all patients respond well to new treatments.
Current research suggests that one characteristic of tumour diseases is immune dysfunction. Immune cells that are supposed to fight the tumour are suppressed by the surrounding tissue of the tumour, its microenvironment.
As a result, T cells, which are the natural immune response against cancer, are restricted and the tumour is allowed to grow and spread uncontrollably. Led by Professor Florian Greten of Georg-Speyer-Haus in Frankfurt, the research team has come one step closer to solving the problem.
Publishing their work in the journal Immunity, they showed that urolithin A recycles and renews mitochondria, the so-called power plants of the cell in T cells, through a process known as mitophagy. Aged and damaged mitochondria in the T cells are removed and replaced by new, functional ones.
This changes the genetic make up of the T cells, which are then more capable of fighting the tumour. Dr Dominic Denk of the Frankfurt University Hospital and first author of the study said: "Our findings are particularly exciting because the focus is not on the tumour cell but on the immune system, the natural defence against cancer.
“This is where reliable therapeutic approaches are still lacking in the reality of colorectal cancer patients. By possibly improving the combination therapy with existing immunotherapies, the study opens up meaningful possibilities for further application in the clinic.
“We hope to use this to sustainably improve the therapy of colorectal cancer, but also of other cancers."
Building on these findings, the researchers plan to apply urolithin A in clinical trials in treatments for people with colon cancer.
Prof Greten, who is also spokesperson of the Frankfurt Cancer Institute (FCI), said: "This work proves once again how successful the interdisciplinary concepts of the FCI are.
“We are very pleased that we can now quickly transfer our results to the clinic and look forward with excitement to the upcoming clinical trials."
