Compared with non-metastatic osteosarcoma cell lines (K7 and Dunn), exosomes derived from metastatic cell lines (K7M3 and DLM8) increased TGFB2 expression in macrophages, inducing M2-type macrophages with increased expression of IL10, TGFB2, and CCL22, and reduced phagocytosis, endocytosis, and macrophage-mediated tumor cell killing (102). This evidence concerns the gene TGFB2 and osteosarcoma.