Bladder squamous cell carcinomas express psoriasin and externalize it to the urine

J Urol. 1996 Jun;155(6):2105-12.


Purpose: To report a single biomarker, psoriasin (Mr 11.0 kd, pI 6.2), a calcium binding protein which is expressed largely by stratified squamous epithelia and is externalized to the urine of bladder squamous cell carcinoma (SCC) bearing patients.

Materials and methods: Protein expression profiles of SCCs obtained immediately after surgery were analyzed by two-dimensional gel electrophoresis and Coomassie blue staining. Protein identity was determined by microsequencing and immunoblotting. Protein expression in cryosections was studied by immunofluorescence.

Results: Four patients with SCC were identified from 100 samples of patients with suspected transitional cell carcinoma (TCC). The protein profiles of the 4 SCCs (56-1, grade III, T4; 181-1, grade I, T3; 219-1, grade III, T3 and 239-1, grade not determined, T2-4) resembled that of keratinocytes, suggesting that these cells express an early developmental pattern of gene expression. Besides expressing markers characteristic of keratinizing stratified squamous epithelia, the SCCs exhibited psoriasin, a protein externalized to the medium by keratinocytes. Immunohistochemistry of 3 of the SCCs with psoriasin antibodies showed that the positive cells were confined chiefly to the "squamous pearls." The presence of psoriasin in the urine of the 4 SCC patients was demonstrated by two-dimensional gel immunoblotting. Similar analysis of 43 urines from patients with bladder tumors other than SCC revealed 7 positives, some of which may reflect squamous differentiation. Analysis of the urine of 13 control individuals (12 males matched by age and a 42-year-old female) revealed 2 positives. Immunoblotting of the SCC patients' serum proteins with psoriasin antibodies failed to reveal the protein.

Conclusion: The results point towards psoriasin, alone or as part of a biomarker profile, as a potential marker for the noninvasive follow-up of patients with SCC.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biomarkers, Tumor / biosynthesis
  • Biomarkers, Tumor / urine*
  • Blotting, Western
  • Calcium-Binding Proteins / biosynthesis
  • Calcium-Binding Proteins / urine*
  • Carcinoma, Squamous Cell / metabolism*
  • Carcinoma, Squamous Cell / urine
  • Carcinoma, Transitional Cell / metabolism
  • Carcinoma, Transitional Cell / urine
  • Case-Control Studies
  • Electrophoresis, Gel, Two-Dimensional
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged
  • S100 Calcium Binding Protein A7
  • S100 Proteins
  • Urinary Bladder / chemistry
  • Urinary Bladder Neoplasms / metabolism*
  • Urinary Bladder Neoplasms / urine


  • Biomarkers, Tumor
  • Calcium-Binding Proteins
  • S100 Calcium Binding Protein A7
  • S100 Proteins
  • S100A7 protein, human