The experiments in HCT-116 tumor-bearing mice (athymic Fox N1-nu/nu mice) showed that oral administration of propolis (500 and 1000 mg/kg every day) for three weeks was associated with a decrease in mitotic cells, and increased p53 and decreased Ki-67 expression of cells in tumor sections, indicating that Iraqi propolis could be promising antitumor agent [166]. The gene discussed is TP53; the disease is neoplasm.