Haplotypes in the 5'-untranslated region of the CYP1A2 gene are inversely associated with lung cancer risk but do not correlate with caffeine metabolism

Environ Mol Mutagen. 2013 Mar;54(2):124-32. doi: 10.1002/em.21747. Epub 2012 Nov 9.

Abstract

In this study, we analyzed the influence of CYP1A2 genetic variation and enzyme activity on lung cancer risk in a high-incidence area. A total of 95 lung cancer patients and 196 controls were genotyped for the -3860G/A, -3113A/G, -2467T/delT, -739T/G, and -163C/A polymorphisms in the 5'-untranslated region of the gene. In addition, a subset of 70 patients and 115 controls were phenotyped by high-performance liquid chromatography determination of the caffeine metabolic ratio (CMR). The -2467T/delT polymorphism and the CYP1A2*1V haplotype (-163C>A, -2467T>delT) were inversely associated with lung cancer risk (odds ratio [OR] = 0.47 [0.2-0.9]; P = 0.02 and OR = 0.13 [0.02-1.0]; P = 0.04; respectively). In addition, the CYP*1A/*1V and *1F (-163C>A)/*1D (-163C>A, -2467T>delT) diplotypes were absent in the patients group, whereas accounting for 7.1% (P = 0.017) and 5.6% (P = 0.037) of controls, respectively. Mean CMR was significantly higher in patients than in controls (10.50 ± 17.31 vs. 6.52 ± 6.26, P = 0.01) but regression analyses did not yield significant ORs for the association with lung cancer risk. Similarly, no significant correlations were found between any genetic variant and enzyme activity. Several CYP1A2 haplotypes and diplotypes containing the -2467delT variant were associated with lower lung cancer risk; however, they did not correlate with significant changes in CYP1A2 metabolic activity toward caffeine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 5' Untranslated Regions*
  • Aged
  • Caffeine / blood
  • Caffeine / metabolism*
  • Caffeine / urine
  • Case-Control Studies
  • Chromatography, High Pressure Liquid
  • Cytochrome P-450 CYP1A2 / genetics*
  • Cytochrome P-450 CYP1A2 / metabolism
  • Female
  • Haplotypes*
  • Humans
  • Incidence
  • Lung Neoplasms / enzymology
  • Lung Neoplasms / epidemiology
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / metabolism
  • Male
  • Middle Aged
  • Polymorphism, Single Nucleotide*
  • Regression Analysis
  • Risk
  • Smoking / adverse effects
  • Spain / epidemiology
  • Surveys and Questionnaires

Substances

  • 5' Untranslated Regions
  • Caffeine
  • CYP1A2 protein, human
  • Cytochrome P-450 CYP1A2