Can Gut Microbiota Influence Response to Immunotherapy in Patients With Melanoma?
Posted: Wednesday, December 4, 2019
A new pilot study reported in Genome Medicine supplements a growing body of evidence suggesting that gut microbiota may determine the efficacy of immunotherapy in patients with melanoma. Brandilyn A. Peters, PhD, of New York University School of Medicine, and colleagues identified transcriptionally expressed metagenomic pathways that appear to be related to progression-free survival. The work may contribute to identifying microbial therapeutic targets for improving survival and immunotherapy outcomes.
The investigators used 16S rRNA gene and shotgun metagenome sequencing to analyze the gut microbiome of 27 patients with melanoma undergoing immunotherapy. Metatranscriptome sequencing was used in 17 of those patients to confirm the transcriptional expression of metagenomic pathways.
A higher microbial community richness was associated with longer progression-free survival (P < .05). Analyses of the overall microbiome composition divided the patient pool into three categories of progression-free survival. Patients in the low-risk group had a 99% lower risk of disease progression than those in the high-risk group (P = .002). The abundance of Bacteroides ovatus, Bacteroides dorei, Bacteroides massiliensis, Ruminococcus gnavus, and Blautia producta were related to shorter progression-free survival, whereas Faecalibacterium prausnitzii, Coprococcus eutactus, Prevotella stercorea, Streptococcus sanguinis, Streptococcus anginosus, and Lachnospiraceae bacterium 3 1 46FAA were related to longer progression-free survival.
“Larger studies with robust microbiome characterization are needed to validate the microbial species and functions related to progression-free survival in melanoma patients on immunotherapy, and whether these relationships differ for adjuvant and metastatic patients or by immunotherapy type,” the authors concluded.
Disclosure: The study authors reported no conflicts of interest.