Immunohistochemical localization of c-myc oncogene product in oral papilloma

The expression of c-myc oncogene products in oral papillomas was studied by using an immunohistochemical method. The oncogene products were detected in 17(70.8%) of the 24 oral papillomas under study. The expression of the products was evaluated, and the histologic localization in proliferating epithelial cells of the oral papillomas was determined. In the basal cell layer, the products were detected in the nuclei of 16 oral papillomas, and in the cytoplasm of 12 oral papillomas. In the nuclei of cells in the spinous cell layer, the products were detected in 4 oral papillomas, and in the cytoplasm of 13 oral papillomas. In the keratinized cells, the products were not detected in the nuclei, but they were identified in the cytoplasm of three oral papillomas. The results suggested that the c-myc oncogene product might play an important role for proliferation and differentiation of the oral papilloma.