Prostate cancer-derived small extracellular vesicles promote osteoclastogenesis and cancer-induced osteolysis via miR-152-3p delivery

Extracellular vesicles (EVs) play critical roles in regulating bone metastatic microenvironment through mediating intercellular communications. Here, we report a direct regulatory mode between tumor cells and osteoclasts in osteolytic metastasis of prostate cancer via vesicular miRNAs transfer. Combined analysis of miRNAs profiles both in tumor-derived small EVs (sEVs) and osteoclasts identified miR-152-3p as a potential osteolytic molecules. Further in vitro experiments showed that sEVs were enriched in miR-152-3p, which targets osteoclastogenic regulator MAFB. Blocking miR-152-3p in sEVs upregulated the expression of MAFB and impaired osteoclastogenesis in recipient osteoclasts. In vivo xenograft mouse model found that blocking of miR-152-3p in sEVs significantly rescued the loss of trabecular architecture, while systemic inhibition of miR-152-3p using antagomiR-152-3p reduced the osteolytic lesions of cortical bone while remaining the basic trabecular architecture. Together, our findings suggest that miR-152-3p carried by prostate cancer-derived sEVs deliver osteolytic signals from tumor cells to osteoclasts, facilitating osteolytic progression in bone metastasis. small RNA sequencing of small extracellular vesicles secreted by three human prostate cancer cell lines.