title: Differentiation-dependent localisation of tissue-type plasminogen activator in human bladder urothelium.
abstract: Human bladder urothelium is able to secrete tissue-type plasminogen activator (tPA). The aim of our study was to analyse localisation of tPA antigen in comparison to differentiation state of cells in samples of histologically normal urothelium and non-invasive tumours of the human urinary bladder. Twenty-five samples of normal urothelium and 31 non-invasive papillary tumours from 36 patients were examined. The presence of tPA antigen was evaluated immunohistochemically. Differentiation of superficial cells was assessed by the presence of urothelial cell differentiation markers, uroplakins (UPs; immunohistochemistry) and cell's apical surface architecture (scanning electron microscopy). All tissue samples stained anti-tPA positive. In normal urothelium, the intensity of anti-tPA staining was the strongest in superficial cells, which were well-differentiated. In tumours, all cell layers stained anti-tPA positive. The intensity of anti-tPA positive reaction in the upper cell layer correlated with the percentage of anti-UP positive superficial cells. Superficial cells showed various differentiation states. The localisation of tPA antigen in human in vivo tissue is not confined to the well-differentiated superficial cells. Our results suggest a positive correlation between tPA secretion and cell differentiation.
authors.affiliation: Institute of Cell Biology, Medical Faculty, University of Ljubljana, Lipiceva 2, 1000 Ljubljana, Slovenia. jana.makuc@mf.uni-lj.si
authors.forename: Jana
authors.initials: J
authors.lastname: Makuc
authors.forename: Andrej
authors.initials: A
authors.lastname: Masera
authors.forename: Bojan
authors.initials: B
authors.lastname: Trsinar
authors.forename: Kristijan
authors.initials: K
authors.lastname: Jezernik
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002291:Carcinoma, Papillary / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010212:Papilloma / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D010959:Tissue Plasminogen Activator / Q000096:biosynthesis*; D001743:Urinary Bladder / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D001749:Urinary Bladder Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D019459:Urothelium / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D010959:Tissue Plasminogen Activator