Lifestyle Factors and Metastatic Melanoma Treatment Response: A Pilot Study on the Role of Mental Health and the Microbiome

Christine Spencer, The University of Texas School of Public Health


Modern therapies for the treatment of metastatic melanoma have greatly improved in recent years, with a proportion of patients deriving long-term benefit. However, the majority still progress and thus there is a great need to understand factors that influence or predict therapeutic response. Recently, research on Body Mass Index (BMI) and the gut microbiome have established important links between host environment and response in melanoma patients. This pilot study investigated the relationship of depressive symptom burden, another important environmental variable in cancer, and its relationship with both treatment response and characteristics of the gut microbiome. Significant statistical interaction was present between depression and BMI in predicting response to therapy, suggesting a significant relationship depressive symptoms and response only when accounting for BMI. Those with higher depressive symptom burden had lower alpha diversity and also lower abundance of pro-response bacteria and higher abundance of anti-response bacteria, although these differences were not statistically significant. There was no clustering pattern observed by depressive symptom burden group in beta diversity plots; however the comparison between microbial communities by depressive symptoms were more pronounced when stratified by BMI group. Other factors including use of pre/probiotics, antibiotics, and consumption of plant fiber (beans) likely also influenced features of the gut microbiome and confounded these relationships. Further work on the associations between depressions, BMI, the microbiome and treatment outcomes is warranted in larger patient cohorts with more in-depth assessment and adjustment for diet and use of probiotics and antibiotics.

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Recommended Citation

Spencer, Christine, "Lifestyle Factors and Metastatic Melanoma Treatment Response: A Pilot Study on the Role of Mental Health and the Microbiome" (2017). Texas Medical Center Dissertations (via ProQuest). AAI10686180.