title: Importance of FAS-1377, FAS-670, and FASL-844 polymorphisms in tumor onset, progression, and pigment phenotypes of Swedish patients with melanoma: a case-control analysis.
abstract: OBJECTIVE
  Human skin melanoma at later stages usually has an extremely poor prognosis. It is of importance to search for biologic markers to identify and monitor individuals at risk for melanoma for early diagnosis and to avoid tumor progression. The FAS gene and its natural ligand (FASL) gene initiate the death signal cascade, playing a central role in the apoptotic signaling pathway and tumor growth and metastasis.
  
  
  METHODS
  In this study, we analyzed polymorphisms in 229 patients with melanoma and 351 age- and gender-matched tumor-free individuals. Genomic DNAs were isolated from mononuclear cells in peripheral vein blood, and the polymorphisms were examined with polymerase chain reaction-restriction fragment length polymorphism techniques. Frequency in distribution of the polymorphisms was compared between the patients with melanoma and the healthy control subjects, and associations with patients' pigment phenotypes, age at diagnosis, and melanoma characteristics were analyzed.
  
  
  CONCLUSIONS
  The FAS-1377, FAS-670, and FASL-844 polymorphisms were not found to be markers of melanoma risk (P > 0.05). In patients with melanoma, frequencies of the FAS-1377, FAS-670, and FASL-844 polymorphisms were different between the patients aged <50 and > or =50 years (P < or = 0.025, P < or = 0.025, and P < or = 0.01). Moreover, the FAS-670 polymorphism correlated with tumor Breslow thickness (P < or = 0.01) and Clark level (P < or = 0.001) and was associated with tumors developing in sun-exposed locations (P < or = 0.001). FAS and FASL were not markers for melanoma risk but might be important in the development and progression of sun-induced melanoma independently of skin type.
authors.affiliation: Division of Dermatology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden. hong.zhang@ibk.liu.se
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Sun
authors.forename: Ingrid
authors.initials: I
authors.lastname: Synnerstad
authors.forename: Inger
authors.initials: I
authors.lastname: Rosdahl
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D018450:Disease Progression; D053222:Fas Ligand Protein / Q000235:genetics*; D005260:Female; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008545:Melanoma / Q000235:genetics*; D008875:Middle Aged; D010641:Phenotype; D011110:Polymorphism, Genetic; D012878:Skin Neoplasms / Q000235:genetics*; D013472:Sunlight; D013548:Sweden; D019014:fas Receptor / Q000235:genetics*
chemical_list: D053222:Fas Ligand Protein; D005819:Genetic Markers; D019014:fas Receptor