THE ESSENTIAL
- Castalagin, a polyphenol found in the Amazonian “camu-camu” berry, may increase the effectiveness of immunotherapy by modifying the microbiome.
- This discovery will soon be tested in patients suffering from lung cancer or melanoma.
Chemotherapy, radiotherapy, hormone therapy… These different treatments are indicated for patients suffering from cancer. Among them, there is also immunotherapy. It is a therapeutic approach that stimulates the immune cells involved in the recognition and destruction of a tumour. This method only works in 30% of people with cancer, according to the Foundation for Medical Research. Recently, Quebec researchers found a solution to increase the effectiveness of immunotherapy. According to the scientists, castalagin, a polyphenol present in the Amazonian “camu-camu” berry, might modify the intestinal microbiota and make the treatment more effective.
Work on mice
To reach this conclusion, the researchers conducted a study, including the results were recently published in the journal Cancer Discovery. Their goal is to transform an “unhealthy microbiome” into a “healthy microbiome” in order to strengthen the immune system. They carried out the work on mice. To assess the effects of castalagin, the authors administered it orally to rodents that had received a fecal transplant from patients resistant to immunotherapy.
Castalagin would promote “an anti-cancer response”
According to the results, castalagin would have modified the composition of the intestinal microbiota, which results in an anti-tumor activity and a stronger response of anti-PD1 antibodies, indicated for the treatment of certain cancers. “Additionally, castalagin induced metabolic changes, resulting in increased bile acids. We found that castalagin binds to the gut bacterium, Ruminococcus bromii, and promotes an anti-cancer response,” can we read in the works. The researchers concluded that castalagin acted as a prebiotic to circumvent resistance to anti-PD1 antibodies.
“Our results pave the way for clinical trials that will use castalagin as an adjunct to drugs called immune checkpoint inhibitors in cancer patients,” said Meriem Messaoudene, author of the research, in a statement.
