Carcinoma associated fibroblasts small extracellular vesicles with low miR-7641 promotes breast cancer stemness and glycolysis by HIF-1α.

Fibroblasts play an important role in cancer development and progression. Small extracellular vesicles (sEVs) are one type of extracellular vesicles, which mediate the interaction between cancer-associated fibroblasts and cancer cells by transferring their contents. However, the roles of sEVs from cancer-associated fibroblasts on breast cancer stem cell properties are largely unraveled. The purpose of this study was to explore the roles of sEVs from cancer-associated fibroblasts on breast cancer progression. The miRNA array data showed a different miRNA profile between CAFs sEVs and normal fibroblasts sEVs. By verification using real-time RT-PCR, the data analysis indicated that miR-7641 levels were lower in sEVs from CAFs compared with NFs. The cellular functions were assayed and the results indicated that CAFs derived sEVs with low miR-7641 levels suppressed breast cancer cell survival, glycolysis, and stem cell properties via the HIF-1α pathway. Collectively, these findings indicated that sEVs from CAFs promoted breast cancer stem cell properties and glycolysis via miR-7641/HIF-1α, which was a possible new way for targeting breast cancer.