(HealthDay News) — Dietary fiber intake and probiotic use may influence the therapeutic response to immunotherapy for melanoma, according to research published online Dec. 21 in Science.
Christine N. Spencer, Ph.D., from The University of Texas MD Anderson Cancer Center in Houston, and colleagues examined fecal microbiota profiles, dietary habits, and commercially available probiotic supplement use in melanoma patients.
The researchers found that, in 128 patients on immune checkpoint blockade (ICB) treatment, higher dietary fiber was associated with significantly improved progression-free survival; the most pronounced benefit was seen in patients with sufficient fiber intake and no probiotic use.
In preclinical models, findings were recapitulated, with impaired treatment response to anti-programmed cell death 1-based therapy demonstrated in mice receiving a low-fiber diet or probiotics; in addition, in the tumor microenvironment, the frequency of interferon-γ-positive cytotoxic T cells was lower.
“In light of these collective results, dietary habits and probiotic supplement use should be considered in patients receiving ICB and in efforts to modulate the gut microbiota,” the authors write. “These factors should be more thoughtfully evaluated in strategies to improve cancer outcomes.”
Several authors disclosed financial ties to the biopharmaceutical industry; several authors are listed as inventors and collaborators on related patent applications.