@article{oai:nagasaki-u.repo.nii.ac.jp:00028022, author = {Seto-Tetsuo, Fumi and Arioka, Masaki and Miura, Koichi and Inoue, Takeru and Igawa, Kazunobu and Tomooka, Katsuhiko and Sasaguri, Toshiyuki}, journal = {International Immunopharmacology}, month = {Feb}, note = {The tumor microenvironment (TME), largely composed of tumor-associated macrophages (TAMs) and cancer-associated fibroblasts (CAFs), plays a key role in cancer progression. A small molecule, differentiation-inducing factor-1 (DIF-1) secreted by Dictyostelium discoideum, is known to exhibit anticancer activity; however, its effect on the TME remains unknown. In this study, we investigated the effect of DIF-1 on the TME using mouse triple-negative breast cancer 4T1-GFP cells, mouse macrophage RAW 264.7 cells, and mouse primary dermal fibroblasts (DFBs). Polarization of 4T1 cell-conditioned medium-induced macrophage into TAMs was not affected by DIF-1. In contrast, DIF-1 decreased 4T1 cell co-culturing-induced C-X-C motif chemokine ligand 1 (CXCL1), CXCL5, and CXCL7 expression in DFBs and suppressed DFB differentiation into CAF-like cells. Additionally, DIF-1 inhibited C-X-C motif chemokine receptor 2 (CXCR2) expression in 4T1 cells. Immunohistochemical analyses of tumor tissue samples excised from breast cancer-bearing mice showed that DIF-1 did not affect the number of CD206-positive TAMs; however, it decreased the number of α-smooth muscle actin-positive CAFs and CXCR2 expression. These results indicated that the anticancer effect of DIF-1 was partially attributed to the inhibition of CXCLs/CXCR2 axis-mediated communication between breast cancer cells and CAFs., International Immunopharmacology, 117, art. no. 109913; 2023}, title = {DIF-1 exhibits anticancer activity in breast cancer via inhibition of CXCLs/CXCR2 axis-mediated communication between cancer-associated fibroblasts and cancer cells}, volume = {117}, year = {2023} }