HOXA6 and meningioma: Meningiomas exhibit epigenetic changes, such as the hypermethylation of tumor suppressor genes like p73 in grade I tumors and genes like TIMP3, maternally expressed 3 (MEG3), the glutathione S-transferase pi gene (GSTP10, homeobox A6 (HOXA6), homeobox A9 (HOXA9), WNK lysine deficient protein kinase 2 (WNK2), and UPK3A, which occur with increasing frequency depending on the grade of malignancy.