EGF and neoplasm: In osteolytic metastases, TGFB and receptor activator of nuclear factor kappa-B ligand (RANKL) play a major role in driving tumour-bone vicious cycle, whereas BMP, epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) signalling have been found to support this cycle in osteoblastic metastases (Ottewell 2016).