PKCα suppresses 7,12-dimethylbenz[a]anthracene-induced skin tumor formation.

BACKGROUND Protein kinase C (PKC)α is distributed in almost all tissues and participates in various signaling pathways. However, the role of PKCα in carcinogenesis remains unclear. In this study, we performed complete skin carcinogenesis in PKCα knockout mice by repeated administration of 7,12-dimethylbenz[a]anthracene (DMBA). MATERIALS AND METHODS Complete skin carcinogenesis was performed by repeated DMBA treatment using PKCα knockout mice. The number of tumors was determined weekly. Tumor types were determined by Hematoxylin and eosin (H & E) analysis. Tumor growth was assayed by proliferating cell nuclear antigen (PCNA) staining. RESULTS In the knockout mice, the average number of tumors was 16.6/mouse at 20 weeks. In contrast, in the wild-type (WT) mice, the tumor number was 6.9/mouse. Growth and malignant grade of tumors in PKCα knockout mice did not differ from those in WT mice. CONCLUSION PKCα suppresses tumor formation, but not tumor growth and progression in skin carcinogenesis.