IL10 and osteosarcoma: Moreover, we performed a lung retention assay in BALB/c mice injected with the highly metastatic K7M2 osteosarcoma murine cells after treatment with IL-6 and IL-10, alone or combined with mifamurtide, and we observed a strong reduction of metastases after IL-6 treatment; inversely, IL-10 treatment caused higher production of metastases (Supplementary Figure S3).