HDAC9 and neoplasm: Understanding that the potent HDAC inhibitory effect of SAHA is associated with the accumulation of acetylated histones and non-histone proteins15, and having observed a probable association between downregulation of HDACs 1, 7, and 8 expression levels, TSA-induced PDAC apoptosis, reduced expression of pluripotent transcription factors and loss of tumor sphere formation efficiency, we sought to validate the relationship between TSA HDAC inhibitory effect and its anticancer activity.