A polymorphism in the CYP17 gene is associated with prostate cancer risk

Int J Cancer. 2000 Aug 1;87(3):434-7. doi: 10.1002/1097-0215(20000801)87:3<434::aid-ijc19>3.0.co;2-g.


CYP17 encodes the enzyme cytochrome P-450c17 alpha, which mediates both 17 alpha-hydroxylase and 17,20-lyase in the steroid biosynthesis pathway. A polymorphism in the 5; promoter region of the CYP17 gene has been described. Steroid hormones, especially androgens, are believed to play a key role in the etiology of prostate cancer. Therefore, polymorphisms in genes involved in the androgen metabolism may affect the risk of prostate cancer. We conducted a case-control study of 63 patients with untreated histologically proven prostate cancer and 126 age-matched control men with benign prostatic hyperplasia (BPH) to determine whether a polymorphism in the CYP17 gene is associated with prostate cancer risk. This polymorphism was investigated by PCR/RFLP using DNA from lymphocytes. The transition (T-->C) in the risk allele (A2) creates a new recognition site for the restriction enzyme MspAI, which permits designation of the wildtype (A1) and the risk allele (A2). The prevalence of the A2/A2 genotype was significantly higher (P = 0.03) in the cancer group (23.8%) than in the BPH control group (9.5%). We found an increased risk in men carrying 2 A2 alleles (OR = 2.80, 95%CI = 1.02-77.76). For carrier with at least 1 A2 allele, the OR was 0.90 (95%CI = 0.43-1.89). After stratification by median age (66 years) at time of diagnosis, a marked increased risk was found in carriers of the A2/A2 genotype older than 66 years (OR = 8.93, 95%CI = 1.78-49.19, P = 0.01). Although the sample size is rather small and the controls are BPH patients, our results suggest that the CYP17A2/A2 genotype may be a biomarker for prostate cancer risk, especially for older men.

MeSH terms

  • Adenocarcinoma / epidemiology
  • Adenocarcinoma / genetics*
  • Aged
  • Alleles
  • Androgens / metabolism*
  • Biomarkers
  • Cell Transformation, Neoplastic / genetics
  • DNA Mutational Analysis
  • Genetic Predisposition to Disease
  • Genotype
  • Humans
  • Loss of Heterozygosity
  • Male
  • Neoplasms, Hormone-Dependent / epidemiology
  • Neoplasms, Hormone-Dependent / genetics*
  • Point Mutation*
  • Polymerase Chain Reaction
  • Polymorphism, Genetic*
  • Polymorphism, Restriction Fragment Length
  • Promoter Regions, Genetic*
  • Prostatic Hyperplasia / genetics
  • Prostatic Neoplasms / epidemiology
  • Prostatic Neoplasms / genetics*
  • Risk
  • Steroid 17-alpha-Hydroxylase / genetics*
  • Steroid 17-alpha-Hydroxylase / physiology


  • Androgens
  • Biomarkers
  • Steroid 17-alpha-Hydroxylase