In our model of DNA damage by gemcitabine in pancreatic cancer, however, gemcitabine-induced DNA damage and apoptosis did not change by gene silencing of BRCA1 or RAD51 (data not shown), and thus the change in DNA repair gene expression upon the DNA damage stimuli may not contribute to the effect of p300 inhibitor on the cytotoxic efficacy of gemcitabine. The gene discussed is RAD51; the disease is pancreatic neoplasm.