HOXA5 and neoplasm: Treatment by TSA increased the expression of SOX2 under overexpression of HOXA5. Thus another transcription factor derived by TSA or histone acetylation status of SOX2 promoter may also involved in the expression of SOX2. However, HOXA5 was reported to be a tumor-suppressor gene that can induce a TP53 tumor-suppressor gene [31] and that it is related to lung development [46].