title: Fas and Fas ligand expression in pancreatic adenocarcinoma.
abstract: BACKGROUND
  Fas and Fas ligand (FasL) mediate apoptosis of tumor cells in immune surveillance, and expression of FasL by tumors may mediate their counterattack on cytotoxic lymphocytes. Both proteins are expressed in most if not all pancreatic carcinoma cell lines, but their study in primary human tumors has been limited.
  
  
  OBJECTIVE
  We performed Fas and FasL immunohistochemical staining on 81 primary pancreaticobiliary or ampullary ductal adenocarcinomas of patients in our institutional database to determine the extent and strength of staining.
  
  
  METHODS
  The expression of Fas and FasL was compared with regard to clinicopathologic variables, K- mutations, and immunoexpression of HER2, p21, p27, and p53.
  
  
  CONCLUSIONS
  Fas was expressed in 19% of patients with strong or intermediate intensity but with variable percentages of tumor cell staining. FasL was expressed in 49% of patients, usually with diffuse expression but variable intensity. Fas expression was more common in women than men, as women had 93% of Fas-positive tumors but only 55% of Fas-negative tumors ( = 0.007), and was associated with strong HER2 expression (67% of Fas-positive versus 18% of Fas-negative patients; = 0.04). Fas expression tended to be less common in blacks (4% had Fas-positive tumors) than whites (22% had Fas-positive tumors; = 0.052). FasL expression tended to be associated with stage 4 disease at diagnosis (24% versus 0%; = 0.07). Neither Fas expression nor FasL expression was associated with survival, a circumstance suggesting that their role, if any, in contributing to the aggressiveness of these tumors is complex.
authors.affiliation: LLC, PathologyOutlines.com
authors.forename: Nat L
authors.initials: NL
authors.lastname: Pernick
authors.forename: Fazlul H
authors.initials: FH
authors.lastname: Sarkar
authors.forename: Pam
authors.initials: P
authors.lastname: Tabaczka
authors.forename: Glenn
authors.initials: G
authors.lastname: Kotcher
authors.forename: John
authors.initials: J
authors.lastname: Frank
authors.forename: N Volkan
authors.initials: NV
authors.lastname: Adsay
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D000368:Aged; D001650:Bile Duct Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D021441:Carcinoma, Pancreatic Ductal / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism*; D053222:Fas Ligand Protein; D005260:Female; D011905:Genes, ras; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology / Q000378:metabolism*; D008875:Middle Aged; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism*; D016019:Survival Analysis; D019014:fas Receptor / Q000276:immunology / Q000378:metabolism*
chemical_list: C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D019014:fas Receptor