HDAC9 and neoplasm: High HDAC expression in several tumors including NSCLC predicts for a poor prognosis and suggests more aggressive tumor behavior.14 Several inhibitors of HDAC have been studied in NSCLC, including vorinostat (SAHA) and entinostat but have failed to improve survival in randomized studies.7, 8, 15 However, the NSCLC studies were done in an unselected patients.