Transitional cell carcinoma expresses high levels of Fas ligand in vivo.
OBJECTIVE
To characterize the Fas-Fas ligand system, a main apoptotic pathway, in transitional cell carcinoma (TCC) of the urinary bladder, by analysing the expression of Fas and Fas ligand (FasL) in TCC samples.


METHODS
Archival paraffin-embedded tissues from 37 patients with TCC were analysed by immunohistochemistry to determine Fas and FasL expression.


RESULTS
Fas and FasL were detected on the cell surface and cytoplasm of respectively 34 (92%) and all cases analysed. The expression of Fas and FasL did not differ with the cytological grade of TCC.


CONCLUSIONS
The high expression of FasL in TCC, reported for the first time in the present study, suggests that FasL may contribute to the immune escape of TCC through killing Fas-bearing lymphocytes. Co-expression of Fas with FasL also suggests that TCC may have pathways resistant to Fas-mediated autocrine cell suicide.
Lee
S H
SH
Department of Pathology and Cancer Research Institute, Catholic University College of Medicine, Seoul, Korea.
Lee
J Y
JY
Park
W S
WS
Kim
S Y
SY
Jang
J J
JJ
Yoo
N J
NJ
D002295:Carcinoma, Transitional Cell / Q000378:metabolism*; D053222:Fas Ligand Protein; D006801:Humans; D007150:Immunohistochemistry; D008024:Ligands; D008562:Membrane Glycoproteins / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism*; D001749:Urinary Bladder Neoplasms / Q000378:metabolism*; D019014:fas Receptor / Q000378:metabolism*
C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008024:Ligands; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; D019014:fas Receptor