ChIP and real-time PCR analysis found that RNA polymerase II (Pol II) and histone acetylation in the UHRF1 promoter were significantly reduced during 12-O-tetradecanoylphorbol-13-acetate (TPA)-mediated leukemia cell differentiation, indicating that the oncogene UHRF1 was tightly repressed. The gene discussed is UHRF1; the disease is leukemia.