Moreover, HDAC1 silencing by siRNA results in cell cycle arrest, cell growth inhibition, and induction of apoptosis in breast and colon cancer cells [7, 8], while HDAC1 overexpression leads to an increase in cell proliferation in prostate cancer cells [9], indicating that HDAC1 stimulates cancer cell growth. The gene discussed is HDAC1; the disease is colonic neoplasm.