Macrophages, the most abundant cells that participate in tumour progression, are the subject of a number of anticancer therapy approaches. Our previous results revealed that an extract of the fungus Coriolus versicolor (CV) has anti-cancer and immunomodulatory properties. The aim of the present study was to investigate whether CV extract-treated triple-negative breast cancer (TNBC) cells can release factors that can reprogram macrophages from pro-tumourigenic to anti-cancer subtypes. RAW 264.7 macrophages were cultured in a conditioned medium (CM) from non-treated 4T1 breast cancer cells (CM-NT) or CV extract-stimulated cells (CM-CV). After treatment, the following macrophage properties were evaluated: cell viability; M1/M2 phenotype (enzyme activities: iNOS and arginase 1; and expression of CD molecules: CD80 and CD163); cytokine concentrations: IL-6, TNF-α, IL-10, TGF-β, MCP-1 and VEGF; migration level; and ROS production. The results revealed that, compared with normal cells, TNBC cells stimulated with CV extract create a microenvironment that promotes a decrease in macrophage viability and migration, intracellular ROS production, and pro-angiogenic cytokine production (VEGF and MCP-1). Moreover, CM-CV decreased the expression of M2 macrophage markers (arginase 1 and CD163; IL-10 and TGF-β) but upregulated the expression of M1 cell markers (iNOS and CD80; IL-6 and TNF-α). We concluded that CV extract modifies the tumour microenvironment and changes macrophage polarisation toward functioning as an anti-tumour agent. Therefore, it is promising to use in the treatment of TNBC-associated macrophages.
Keywords: Coriolus versicolor; Breast cancer; Conditioned medium; Cytokines; Macrophage phenotype.
© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.