title: Lack of an association of programmed cell death-1 PD1.3 polymorphism with risk of hepatocellular carcinoma susceptibility in Turkish population: a case-control study.
abstract: OBJECTIVE
  The programmed cell death-1 (PD-1) is a potent immunoregulatory molecule which is responsible for the negative regulation of T-cell activation and peripheral tolerance. Recently, overexpression of PD-1 has been reported to contribute to immune system evasion and poor survival of hepatocellular carcinoma (HCC). A common single nucleotide polymorphism in intron 4 of PD-1 gene called PD-1.3 has been reported to influence PD-1 expression, but its association with HCC has yet to be investigated. The aim of the present study was to investigate whether this polymorphism could be involved in the risk of HCC susceptibility.
  
  
  METHODS
  The genotype frequency of PD-1.3 polymorphism was determined by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 236 subjects with HCC and 236 cancer-free control subjects matched on age, gender, smoking and alcohol status.
  
  
  RESULTS
  No statistically significant differences were found in the genotype distributions of the PD-1.3 polymorphism among HCC and cancer-free control subjects (P=0.22).
  
  
  CONCLUSIONS
  Our results demonstrate for the first time that the PD-1.3 polymorphism has not been in any major role in genetic susceptibility to hepatocellular carcinogenesis, at least in the population studied here. Independent studies are needed to validate our findings in a larger series, as well as in patients of different ethnic origins.
authors.affiliation: Adıyaman University, Adıyaman School of Health, Department of Nursing, 02040 Adıyaman, Turkey. slymnbyrm81@gmail.com
authors.forename: Süleyman
authors.initials: S
authors.lastname: Bayram
authors.forename: Hikmet
authors.initials: H
authors.lastname: Akkız
authors.forename: Yakup
authors.initials: Y
authors.lastname: Ülger
authors.forename: Aynur
authors.initials: A
authors.lastname: Bekar
authors.forename: Ersin
authors.initials: E
authors.lastname: Akgöllü
authors.forename: Selçuk
authors.initials: S
authors.lastname: Yıldırım
mesh_terms: D001483:Base Sequence; D006528:Carcinoma, Hepatocellular / Q000235:genetics*; D016022:Case-Control Studies; D017931:DNA Primers; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics*; D008297:Male; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D061026:Programmed Cell Death 1 Receptor / Q000235:genetics*; D014421:Turkey
chemical_list: D017931:DNA Primers; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor