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IKKalpha is required to maintain skin homeostasis and prevent skin cancer.

ABSTRACT: It has long been known that excessive mitotic activity due to H-Ras can block keratinocyte differentiation and cause skin cancer. It is not clear whether there are any innate surveillants that are able to ensure that keratinocytes undergo terminal differentiation, preventing the disease. IKKalpha induces keratinocyte terminal differentiation, and its downregulation promotes skin tumor development. However, its intrinsic function in skin cancer is unknown. Here, we found that mice with IKKalpha deletion in keratinocytes develop a thickened epidermis and spontaneous squamous cell-like carcinomas. Inactivation of epidermal growth factor receptor (EGFR) or reintroduction of IKKalpha inhibits excessive mitosis, induces terminal differentiation, and prevents skin cancer through repressing an EGFR-driven autocrine loop. Thus, IKKalpha serves as an innate surveillant.

SUBMITTER: Liu B

PROVIDER: S-EPMC7263012 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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IKKalpha is required to maintain skin homeostasis and prevent skin cancer.

Liu Bigang B Xia Xiaojun X Zhu Feng F Park Eunmi E Carbajal Steve S Kiguchi Kaoru K DiGiovanni John J Fischer Susan M SM Hu Yinling Y

Cancer cell 20080901 3

It has long been known that excessive mitotic activity due to H-Ras can block keratinocyte differentiation and cause skin cancer. It is not clear whether there are any innate surveillants that are able to ensure that keratinocytes undergo terminal differentiation, preventing the disease. IKKalpha induces keratinocyte terminal differentiation, and its downregulation promotes skin tumor development. However, its intrinsic function in skin cancer is unknown. Here, we found that mice with IKKalpha d ...[more]

PMID: 18772111

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IKKα Is Required to Maintain Skin Homeostasis and Prevent Skin Cancer

Project description:It has long been known that excessive mitotic activity due to H-Ras can block keratinocyte differentiation and cause skin cancer. It is not clear, however, whether there are any innate surveillants that ensure keratinocytes undergoing terminal differentiation, preventing the disease. IKKα induces keratinocyte terminal differentiation and its reduction promotes skin tumor development. However, its nature function in skin cancer is unknown. Here we found that mice with IKKα deletion in keratinocytes or in hair follicle keratinocytes developed a thickened epidermis and spontaneous squamous cell-like carcinomas. Inactivation of epidermal growth factor receptor (EGFR) or reintroduction of IKKα inhibited excessive mitosis, induced terminal differentiation, and prevented skin cancer through an EGFR-driven autocrine loop in mice. Thus, IKKα serves as an innate surveillant.

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Intact endothelial autophagy is required to maintain vascular lipid homeostasis.

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