ENHANCED EXPRESSION OF A TUMOR-CELL-DERIVED COLLAGENASE-STIMULATORY FACTOR IN UROTHELIAL CARCINOMA - ITS USEFULNESS AS A TUMOR-MARKER FOR BLADDER CANCERS

A mouse monoclonal antibody (MAb) EIIF4, previously raised against the tumor-cell-derived collagenase-stimulatory factor (TCSF) from LX-I hu man lung-carcinoma cells, has been used to define the expression and d istribution of TCSF in human non-neoplastic urothelium and tumors of t he urinary bladder. Immunohistochemically, TCSF was detected in 27/28 transitional-cell carcinomas (TCC) of the bladder, of which 23 were ju dged to be positive for TCSF according to objective criteria. Twenty-f our of 28 non-neoplastic urothelium from 22 individuals were. judged t o be negative for TCSF by this criteria. However, TCSF immunostaining that was confined to the superficial umbrella cells was frequently obs erved in non-neoplastic urothelium. In bladder carcinomas, TCSF was in most cases demonstrated in the majority of cells, including at the in vasion front. Its localization to the cell membrane was demonstrated b y immunoelectron microscopy. The high level of expression of TCSF in b ladder tumors, but not in non-neoplastic urothelium, was also demonstr ated by immunoblotting of tissue extracts. Furthermore, EIIF4 immunost aining identified tumor cells obtained from bladder washings or voided urine and detected more TCC cases than conventional cytology. Since T CSF immunostaining was positive even in low-grade TCC (immunohistochem ically and immunocytochemically in 4/5 TCC grade I), the application o f TCSF immunostaining to urine cytology appears promising as a valuabl e adjunct to conventional methods in the clinical evaluation of patien ts with TCC. (C) 1993 Wiley-Liss, Inc.