Inhibition of HDAC activity may occur in human colon cancer cells, with an increase in histone H3 acetylation in extensive histone modification statuses, such as induction of TNFR, Fas, FasL, and p21 genes, via histone acetyltransferase (HAT) p300 (Bolden et al., 2006; Kouzarides, 2007; Rajendran et al., 2011). The gene discussed is HDAC9; the disease is malignant colon neoplasm.