Tissue inhibitor of metalloprotease 3 (TIMP3) is the most known tumor suppressor gene transcriptionally repressed by hypermethylation in meningiomas; hypermethylation of the TIMP3 gene is a marker of an aggressive, high-grade meningioma phenotype: in fact, grade I tumors display a methylation degree of TIMP3 gene promoter clearly less pronounced than grade II/III tumors [215]. The gene discussed is TIMP3; the disease is meningioma.