RNA-seq of mouse RAW264.7 macrophages treated with bone-metastatic lung cancer-derived exosomes to investigate osteoclast differentiation

This study aimed to elucidate the mechanism by which exosomes from bone-metastatic Lewis lung carcinoma (BM-LLC) cells promote osteolytic metastasis. We performed RNA-seq on mouse RAW264.7 macrophages (osteoclast precursors) treated with exosomes derived from either non-metastatic (NC-LLC) or bone-metastatic (BM-LLC) Lewis lung carcinoma cells. The goal was to identify differentially expressed genes and key regulatory pathways involved in exosome-induced osteoclast differentiation. Integrated analysis with small RNA sequencing data from the exosomes identified the miR-484-PECAM1 axis as a critical driver of this process. Our findings reveal that BM-LLC exosomes deliver miR-484 to recipient macrophages, repress PECAM1 expression, and subsequently upregulate osteoclastogenic markers (TRAP, CTSK, RANKL) and master transcription factors (NFATc1, c-Fos), thereby reprogramming osteoclastogenesis and driving bone destruction.