title: Polymorphism of T-cell receptor gamma short tandem repeats as a susceptibility risk factor of hepatocellular carcinoma.
abstract: BACKGROUND
  T-cells play a critical role in the immunological surveillance network against cancer formation. The activation of T-cells is initiated by binding of T-cell receptors (TCR) with antigen epitopes. Polymorphisms of TCR-gamma microsatellite (short tandem repeats, STR) marker has been associated with early-onset colorectal cancer. The aim of this study was to test the relationship of TCR-gamma STR genetic polymorphisms and hepatocellular carcinoma (HCC).
  
  
  METHODS
  A total of 225 chronic hepatitis B- or C-related HCC and liver cirrhosis patients were enrolled in this study. The other 225 sex-matched cirrhotic patients without HCC were recruited as controls. Their TCR-ygammaSTR polymorphisms at loci D7S1818 and D7S2206 were measured by polymerase chain reaction. Dietary habits and other possible risk factors for HCC were also assessed by a structured questionnaire.
  
  
  RESULTS
  Compared to controls, the HCC patients were older in age (64.9 +/- 10.3 vs. 53.5 +/- 10.1 years, p < 0.001) and had a higher percentage of family history of HCC (13.3% vs. 7.6%, p = 0.045) and habitual alcohol use (23.1% vs. 15.6%, p= 0.042). A total of 20 genotypes of TCR-gamma D7S1818 STR were detected. Of these, the genotype 16 (13/14 of repeat number of GA A) had a higher percentage in the HCC groups than in the controls (13.8% vs. 6.7%, p = 0.013). After adjustment for age, family history of HCC and habitual alcohol use, the TCR-gamma genotype 16 remained a significant risk factor for HCC (OR: 2.18, 95% CI: 1.02-4.65, p= 0.045).
  
  
  CONCLUSIONS
  The TCR-gamma STR polymorphism may be associated with HCC susceptibility.
authors.affiliation: Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC.
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Hsu
authors.forename: Yi-Shin
authors.initials: YS
authors.lastname: Huang
authors.forename: Shi-Yi
authors.initials: SY
authors.lastname: Yang
authors.forename: Full-Young
authors.initials: FY
authors.lastname: Chang
authors.forename: Shou-Dong
authors.initials: SD
authors.lastname: Lee
mesh_terms: D000368:Aged; D001483:Base Sequence; D006528:Carcinoma, Hepatocellular / Q000235:genetics*; D016022:Case-Control Studies; D017931:DNA Primers; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000235:genetics*; D012307:Risk Factors; D020080:Tandem Repeat Sequences
chemical_list: D017931:DNA Primers; D016692:Receptors, Antigen, T-Cell, gamma-delta