Repressed Blautia-acetate immunological axis underlies chronic stress promoted breast cancer progression

Chronic stress is a known risk factor for breast cancer, yet the underlying mechanisms are unclear. This study explores the potential involvement of microbial and metabolic signals in chronic stress-promoted breast cancer progression, revealing that reduced abundances of Blautia and its metabolite acetate may contribute to this process. Treatment with Blautia and acetate increased antitumor responses of CD8+ T cells and reversed stress-promoted breast cancer progression. Depressed patients exhibit lower abundances of Blautia and acetate, and breast cancer patients with depression display lower abundances of acetate, decreased numbers of tumor-infiltrating CD8+ T cells, and an increased risk of metastasis. These results suggest that Blautia-derived acetate plays a crucial role in modulating the immune response to breast cancer, and its reduction may contribute to chronic stress-promoted cancer progression. Our findings advance the understanding of microbial and metabolic signals implicated in cancer with depression and may provide new therapeutic options for breast cancer patients with depression