Ornithine Decarboxylase Expression in Cutaneous Papillomas in SENCAR Mice Is Associated with Altered Expression of Keratins 1 and 10

The study investigated the expression of ornithine decarboxylase (ODC) and keratins in early papillomas in SENCAR mice to identify markers for early stages of skin tumorigenesis. Tumors were induced using 7,12-dimethylbenzanthracene and promoted with 12-O-tetradecanoylphorbol-13-acetate. In early papillomas, keratin 1 (K1) showed patchy staining, while keratin 10 (K10) was minimally expressed, indicating altered differentiation patterns. ODC expression was intense and diffuse in suprabasal cells of papillomas, correlating with decreased K1 and K10 expression. These findings suggested that high ODC expression and reduced K1 and K10 could serve as phenotypic markers for early tumorigenesis in mouse skin.