CDKN2A and meningioma: Additionally, inactivation through hypermethylation of CpG islands has also been reported in a smaller proportion of meningiomas, including hypermethylation of CDKN2A/p16INKa in 8-17% of cases, CDKN2A/p14ARF in 4-13%, and CDKN2B/p15ARF in 4% of these tumors [17, 35].