Brazilian berry being evaluated for cancer treatment in Canadian study

New research on the Brazilian camu camu berry has found the fruit to be effective in treating cancers.

Researchers from the University of Montreal Hospital Research Centre (CRCHUM) discovered that castalagin, a polyphenol from the Amazonian fruit camu camu, increased the efficacy of immunotherapy in mice by modifying their microbiome.

The study, published in the journal, Cancer Discovery, demonstrated that supplementation with the camu camu berry in mice shifted gut microbial composition, which translated into antitumor activity and a stronger anti-PD-1 response. 

Researchers orally administered castalagin to mice that had received a fecal transplant from patients resistant to immune checkpoint inhibitors (ICI). They found that castalagin enriched for bacteria associated with efficient immunotherapeutic responses (Ruminococcaceae and Alistipes) improved the CD8+/Foxp3+CD4+ ratio within the tumor microenvironment, according to the study. Castalagin also induced metabolic changes, resulting in an increase in taurine conjugated bile acids.

In addition, the scientists found that the compound binds to a beneficial intestinal bacteria, Ruminococcus bromii, and promotes an anticancer response. The results showed castalagin acts as a prebiotic to circumvent anti-PD-1 resistance.

The first clinical trial testing combining the camu camu berry and ICIs on 45 patients with lung cancer or melanoma is slated to begin this month at the Centre hospitalier de l'Université de Montréal and the Jewish General Hospital.