Background
Treatment outcomes for early-stage breast cancer have improved dramatically, and attention is turning towards reducing treatment-associated morbidity. Early-stage breast cancer patients treated with chemotherapy have an increased risk of developing weight gain and even metabolic disease, which can result in increased morbidity and reduced quality of life. A study from the University of Alberta looked at breast cancer patients treated either with chemotherapy or endocrine (anti-estrogen) therapy and compared changes in body weight and composition together with the analysis of temporal changes in gut microbiota and inflammatory biomarkers (measured using the Olink® Target 96 Inflammation panel).
Outcome
In their patient cohort, chemotherapy (but not endocrine treatment) resulted in statistically and clinically significant weight gain and colonic inflammation in conjunction with notable gut microbiome changes. Plasma proteomics showed increases in pro-inflammatory cytokines/chemokines following treatment with chemotherapy that were not seen in patients on endocrine therapy only. In fact, the inflammatory signature in patients receiving endocrine therapy was the opposite of that seen with chemotherapy treatment, with a general reduction in inflammatory biomarkers seen.
Chemotherapy-treated patients showed a sharp rise in circulating L6, IL8 & IL17 levels, along with multiple chemokines (CCL3, CCL23, CCL7, CCL20, CXCL10, CX3CL1) that are associated with interferon-dependent inflammatory signaling. These results confirmed the association of chemotherapy treatment with weight gain and suggest that alterations in the gut microbiome may contribute to this through the induction of systemic inflammation. This also indicates that the gut microbiome may be a future target for intervention in preventing chemotherapy-dependent anthropometric changes in cancer patients.
