Gut microbiota composition in chemotherapy and targeted therapy of patients with metastatic colorectal cancerOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
Researchers examined whether gut microbiota composition relates to treatment outcomes in metastatic colorectal cancer patients receiving chemotherapy plus targeted therapy. They compared patients grouped by response (partial response versus progressive disease) and by targeted agent (cetuximab versus bevacizumab).
How was it studied?
Stool samples were collected from 110 patients with metastatic colorectal cancer before starting combined chemotherapy and targeted therapy. Of these, 55 patients with a clear partial response (31) or progressive disease (24) after at least 12 treatment cycles were analyzed by metagenomic sequencing for microbial diversity and species abundance.
What did they find?
The partial-response group, and the bevacizumab partial-response subgroup, had significantly higher microbial diversity than the progressive-disease groups. Klebsiella quasipneumoniae showed the largest fold-change increase in the progressive-disease group, while Lactobacillus and Bifidobacterium species were also more abundant there. Fusobacterium nucleatum was about 32 times more abundant in the progressive-disease group than in the partial-response group.
Why it matters
Higher gut microbial diversity tracked with better treatment response in metastatic colorectal cancer, suggesting the microbiome may influence outcomes of chemotherapy plus targeted therapy. The authors note findings were heterogeneous and need further validation, particularly in Taiwanese populations.