HDAC9 and glioblastoma: Overall, combining EGFR targeted therapy with HDAC inhibition reduces the development of resistance in glioblastoma cells in vitro by preventing compensatory overexpression of wild-type EGFR/EGFRvIII and represses wtEGFR/EGFRvIII in cells that have attained resistance to targeted therapy by increased expression of these oncogenes, thereby resensitizing the cells to targeted therapy.