Expression of desmosomal proteins in squamous cell carcinomas of the skin

J Cutan Pathol. 2003 Nov;30(10):621-30. doi: 10.1034/j.1600-0560.2003.00122.x.

Abstract

Background: Desmosomal proteins are well established markers of epithelial differentiation. Down-regulation of desmosomal proteins has been suggested to be a sign of reduced adhesiveness in metastasizing cells.

Methods: We examined actinic keratoses, Bowen's disease, and squamous cell carcinoma (SCC) of the skin for the expression of desmosomal proteins using isoform-specific antibodies on paraffin-embedded sections. Evaluation was performed qualitatively in comparison to the epidermis and semiquantitatively using an area-intensity-score.

Results: We found no qualitative correlation of desmoplakin or plakoglobin expression with risk of metastasis. Plakophilin 1, desmoglein 1, and the desmocollins 1-3 were found to be heterogeneously expressed in all neoplasms without significant correlation to aggressive tumor behavior. Plakophilin 2 was not expressed in any of the neoplasms examined. As most striking finding, desmoglein 2 was up-regulated qualitatively in half of all neoplasms examined and showed a significant higher proportion of positive cells in high-risk SCC than in low-risk SCC.

Conclusions: Desmosomal proteins are highly regulated in cutaneous SCC. Only desmoglein 2 expression correlates with risk of metastasis. Desmosomes may still be functional in metastasizing tumor cells.

MeSH terms

  • Bowen's Disease / metabolism
  • Carcinoma, Squamous Cell / metabolism*
  • Cytoskeletal Proteins / metabolism
  • Desmocollins
  • Desmoglein 1
  • Desmoglein 2
  • Desmogleins
  • Desmoplakins
  • Desmosomes / metabolism*
  • Epidermis / metabolism
  • Humans
  • Immunohistochemistry
  • Keratosis / metabolism
  • Membrane Proteins / metabolism*
  • Plakophilins
  • Protein Isoforms / metabolism
  • Proteins / metabolism
  • Racemases and Epimerases
  • Skin Neoplasms / metabolism*
  • gamma Catenin

Substances

  • Cytoskeletal Proteins
  • DSG1 protein, human
  • DSG2 protein, human
  • DSP protein, human
  • Desmocollins
  • Desmoglein 1
  • Desmoglein 2
  • Desmogleins
  • Desmoplakins
  • Membrane Proteins
  • PKP1 protein, human
  • PKP2 protein, human
  • Plakophilins
  • Protein Isoforms
  • Proteins
  • gamma Catenin
  • Racemases and Epimerases
  • NDP-4-keto-6-deoxy-D-glucose 3',5'-epimerase