SPP1 and neoplasm: Primary tumor-derived factors reported to be involved in these processes are GM-CSF, G-CSF, Flt3L, IGF1, hypoxia-installed lysyl oxidase (LOX), MMP2, tumor necrosis factor alpha (TNFα), VEGF, PlGF, TGFβ and osteopontin (5, 100–103, 106, 110–113, 121, 126, 132, 137, 138) as well as exosome-based delivery of MET oncoproteins and TLR3 triggering small nuclear RNAs (114, 149).