Secondly, mineralisation could by stimulated by either the release of bone matrix proteins (OSC, OPN, Collagen type I) upon bone resorption (Cox and Morgan, 2013) or by tumour-derived growth factors released by disseminated tumour cells (Clines and Guise, 2005), both of which can stimulate resident osteoblasts to increase bone deposition. Here, SPP1 is linked to neoplasm.