CCAAT/enhancer binding protein-β is a mediator of keratinocyte survival and skin tumorigenesis involving oncogenic Ras signaling

摘要

The basic leucine zipper transcription factor CCAAT/enhancer binding protein-β (C/EBPβ) is expressed in many cell types, including kera- tinocytes. C/EBPβ activity can be increased by phosphorylation through pathways stimulated by oncogenic Ras, although the bio- logical implications of Ras-C/EBPβ signaling are not currently under- stood. We report here that C/EBPβ-nullizygous mice are completely refractory to skin tumor development induced by a variety of carcin- ogens and carcinogenesis protocols, including 7,12-dimethylbenz [a]anthracene-initiation/12-O-tetradecanoylphorbol 13-acetate pro- motion, that produce tumors containing oncogenic Ras mutations.