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Published on: January 21, 2012

Expression of the cyclin-dependent kinase inhibitor p27 in keratoacanthoma

W Hu1, T Cook, C W Oh

  • 1Department of Dermatology, St Louis University Health Science Center, Missouri, USA.

Journal of the American Academy of Dermatology
|February 25, 2000
PubMed
Abstract

Insights

p27(kip) protein is present in regressing keratoacanthomas but not expanding ones. This suggests p27(kip) may promote keratoacanthoma regression and could be a therapeutic target.

Area of Science:

  • Dermatology
  • Oncology
  • Cell Biology

Background:

  • Keratoacanthomas exhibit rapid growth followed by spontaneous regression.
  • Cell cycle regulation involves cyclin and cyclin-dependent kinase complexes.
  • p27(kip) is an inhibitor of cyclin-dependent kinase complexes, potentially inducing cell quiescence.

Purpose of the Study:

  • To investigate the expression of p27(kip) in both expanding and regressing keratoacanthomas.
  • To determine the role of p27(kip) in the regression process of keratoacanthomas.

Main Methods:

  • Immunohistochemical analysis was employed to detect and quantify p27(kip) expression.
  • The study included samples from 5 expanding and 15 regressing keratoacanthomas.

Main Results:

  • p27(kip) was observed in the nuclei of suprabasilar keratinocytes in normal epidermis.
  • Expanding keratoacanthomas showed minimal p27(kip) expression in atypical keratinocytes (1.25 cells/HPF).
  • Regressing keratoacanthomas demonstrated significant p27(kip) expression in atypical keratinocytes (55.1 cells/HPF), with P < .001.

Conclusions:

  • The presence of p27(kip) in regressing keratoacanthomas, contrasted with its absence in expanding ones, implicates it in the regression mechanism.
  • p27(kip) emerges as a potential therapeutic target for promoting keratoacanthoma regression.

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