Translator Disclaimer
1 March 2000 P53-Dependent UVB Responsiveness of Human Keratinocytes Can Be Altered by Cultivation on Cell Cycle-arrested Dermal Fibroblasts
Author Affiliations +

In cultured human keratinocytes, the tumor suppressor p53 acts as a control element in the protective response to UVB radiation and is affected by a variety of factors linked to cellular adhesion and differentiation. Because keratinocytes within the epidermis are not a homogeneous population but differ in their proliferative capacity and differentiation status, we compared the UVB responsiveness of primary keratinocyte populations isolated from various skin biopsies using p53 expression as a marker for their sensitivity to UVB. Besides keratinocytes exhibiting a UVB dose- and time-dependent upregulation of p53, keratinocyte populations were detected with high p53 expression levels even without irradiation. Such keratinocytes did not regulate p53 expression in response to UVB. Furthermore their p53-mediated UVB response was influenced by cocultivation with human dermal fibroblasts (HDF) but not with cell cycle-arrested human normal keratinocytes or HaCaT keratinocytes. When these cells were cultivated together with arrested HDF, they did not only reveal increased p53 expression levels after UVB treatment but also a more pronounced transcriptional activation of the p53 downstream target gene p21. These findings indicate that the UVB response of keratinocytes, specifically the activation of the tumor suppressor p53, is heterogeneous and can be affected by growth conditions.

Katrin Will, Maresa Neben, Thomas Schmidt-Rose, Wolfgang Deppert , Klaus-Peter Wittern, and Jörg Bergemann "P53-Dependent UVB Responsiveness of Human Keratinocytes Can Be Altered by Cultivation on Cell Cycle-arrested Dermal Fibroblasts," Photochemistry and Photobiology 71(3), 321-326, (1 March 2000).<0321:PDUROH>2.0.CO;2
Received: 3 August 1999; Accepted: 1 December 1999; Published: 1 March 2000

This article is only available to subscribers.
It is not available for individual sale.

Get copyright permission
Back to Top