Impacts of breast cancer and chemotherapy on gut microbiome, cognitive functioning, and mood relative to healthy controls

Abstract

Women diagnosed with breast cancer undergoing chemotherapy experience cognitive impairment, symptoms of anxiety and depression, and physical side effects including disruption in the diversity and community composition of the gut microbiome. To date, there is limited research exploring the associations among these specific challenges. The present cross-sectional study explored the associations of self-reported cognitive functioning, depression, and anxiety symptoms, and gut microbiome diversity and community composition in women who were diagnosed with and undergoing chemotherapy treatment for breast cancer (BC) compared to cancer-free healthy controls (HC). The BC group displayed higher rates of cognitive dysfunction (p < 0.001) and depressive symptoms (p < 0.05) relative to HC. There was a significant difference in microbiome community composition between BC and HC, particularly characterized by a decreased relative abundance of the mucin-degrading genus Akkermansia in BC compared to HC (p < 0.05). Association models identified significant associations among group, cognitive, depression, and microbiome variables (p < 0.001). Overall, the study identified that BC participants experienced significant differences in self-reported cognitive functioning, self-reported depression symptoms, microbiome community composition, and mucin-degrading bacteria of the gut-mucosal barrier, relative to HC. The present study is consistent with the hypothesis that gut microbiome community composition impacts a woman’s experience with breast cancer and treatment suggesting that microbiome-based interventions have potential for improving quality of life outcomes in individuals with breast cancer.

Microbial Therapy and Breast Cancer Management: Exploring Mechanisms, Clinical Efficacy, and Integration within the One Health Approach

“…A study by Aarnoutse et al (2022) identified a significant reduction in species richness (p = 0.042) within the gut microbiomes of estrogen-receptor-positive BC patients undergoing treatment with (neo)adjuvant chemotherapy drugs [37]. A similar trend was observed in patients undergoing chemotherapy, as documented by Bilenduke et al (2022), and concentrations returned to baseline post-treatment [38]. Conversely, Horigome et al (2019) found no notable shifts in gut microbiome composition between chemotherapy-treated BC survivors and non-chemotherapy-treated survivors [39].…”

Microbial Therapy and Breast Cancer Management: Exploring Mechanisms, Clinical Efficacy, and Integration Within the One Health Approach

“…A study by Aarnoutse et al, (2022) identified a significant reduction in species richness (p = 0.042) within the gut microbiome of estrogen receptor-positive BC patients during treatment with (neo)adjuvant chemotherapy drugs [89]. A similar trend in decreased gut microbiome richness during chemotherapy was documented by Bilenduke et al, (2022), which later returned to baseline post-treatment [90]. Conversely, Horigome et al (2019) found no notable shifts in gut microbiome composition between chemotherapy-treated BC patients and untreated counterparts [91].…”

“…A depleted microbial richness is linked to intensified depression symptoms, heightened fear of cancer recurrence, and the onset of diarrhea in BC patients undergoing chemotherapy [89,90,93]. Chemotherapy-associated cognitive impairment (CACI) is a widely documented side effect in BC patients, with deficits manifesting in memory retention, processing speed, and visuospatial ability [92,[94][95][96].…”

Signalling cognition: the gut microbiota and hypothalamic-pituitary-adrenal axis

“…The gut is often an unwarranted target of chemotherapeutic agents, with mucositis being a common complication ( 449 ). Women diagnosed with breast cancer undergoing chemotherapy experience disruption in GM diversity and composition, cognitive impairment, and symptoms of stress, such as anxiety and depression ( 450 ).…”