EGF and cholesteatoma: Moreover, many of these cytokines promote peri-matrix angiogenesis (EGF, PDGF, IL-8, TGFα) and osteoclastogenesis/bone resorption (IL-1, IL-6, PTHrP, receptor activator of nuclear factor kappa-B ligand (RANKL), which are both responsible for cholesteatoma proliferation and local aggressiveness [10,24,25].