[The "Fas counterattack": a mechanism for immune evasion in human hilar cholangiocarcinomas].
OBJECTIVE
To investigate FasL expression in hilar cholangiocarcinoma tissues and cultured cholangiocarcinoma cells, and to assess the its ability to induce apoptosis.


METHODS
The expression of FasL in 48 specimens of human hilar cholangiocacinoma resected in operation and cultured QBC939 cholangiocarcinoma cell line was detected by RT-PCR, immunohistochemistry, and Western blotting. TUNEL and flow cytometry were used to detect apoptotic cells.


RESULTS
Prevalent expression of FasL was detected in 48 resected hilar cholangiocarcinomas examined. TUNEL staining disclosed a high level of cell death among lymphocytes infiltrating FasL positive areas of tumor. FasL mRNA and protein was expressed in cholangiocarcinoma cells. Apoptosis was seen in 60% of Jurkat cells cultured together with QBC939 Cholangiocarcinoma cells.


CONCLUSIONS
The hilar cholangiocarcinoma eludes immunological surveillance by inducing, via the Fas/FasL system, the apoptosis of activated lymphocytes.
Department of General Surgery, Tongji Hospital, Wuhan 430030, China.
Ziyu
Z
Li
Lin
L
Zhang
Shengquan
S
Zou
D017209:Apoptosis; D018281:Cholangiocarcinoma / Q000276:immunology / Q000378:metabolism*; D053222:Fas Ligand Protein; D006801:Humans; D007109:Immunity; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000276:immunology / Q000378:metabolism*; D014407:Tumor Cells, Cultured
C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins