Although gene methylation can be detected across all grades of meningiomas, the frequency varies between benign and malignant tumors, and genes (e.g., TIMP3, GSTP1, MEG3, HOXA6, HOXA9, PENK, WNK2, and UPK3A genes) have an increased frequency according to the WHO grade (12). Here, HOXA9 is linked to meningioma.