KDM5A overexpression contributes to TMZ resistance, and its inhibition enhances the treatment response.104 HDAC9, a regulator of Hippo signaling via TAZ activation, promotes GBM progression, highlighting HDAC9 inhibition as a therapeutic strategy.105 Ras-related protein on chromosome 22 (RRP22) functions as a tumor suppressor, with low expression linked to increased tumor grade and reduced survival. This evidence concerns the gene HDAC9 and glioblastoma.