We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
15q12 Variants, Sputum Gene Promoter Hypermethylation, and Lung Cancer Risk: A GWAS in Smokers.
- Authors
Shuguang Leng; Yushi Liu; Weissfeld, Joel L.; Thomas, Cynthia L.; Younghun Han; Picchi, Maria A.; Edlund, Christopher K.; Willink, Randall P.; Gaither Davis, Autumn L.; Kieu C. Do; Tomoko Nukui; Xiequn Zhang; Burki, Elizabeth A.; Van Den Berg, David; Romkes, Marjorie; Gauderman, W. James; Crowell, Richard E.; Tesfaigzi, Yohannes; Stidley, Christine A.; Amos, Christopher I.
- Abstract
Background: Lung cancer is the leading cause of cancer-related mortality worldwide. Detection of promoter hypermethylation of tumor suppressor genes in exfoliated cells from the lung provides an assessment of field cancerization that in turn predicts lung cancer. The identification of genetic determinants for this validated cancer biomarker should provide novel insights into mechanisms underlying epigenetic reprogramming during lung carcinogenesis. Methods: A genome-wide association study using generalized estimating equations and logistic regression models was conducted in two geographically independent smoker cohorts to identify loci affecting the propensity for cancer-related gene methylation that was assessed by a 12-gene panel interrogated in sputum. All statistical tests were two-sided. Results: Two single nucleotide polymorphisms (SNPs) at 15q12 (rs73371737 and rs7179575) that drove gene methylation were discovered and replicated with rs73371737 reaching genome-wide significance (P = 3.3 x 10-8). A haplotype carrying risk alleles from the two 15q12 SNPs conferred 57% increased risk for gene methylation (P = 2.5 x 10-9). Rs73371737 reduced GABRB3 expression in lung cells and increased risk for smoking-induced chronic mucous hypersecretion. Furthermore, subjects with variant homozygote of rs73371737 had a two-fold increase in risk for lung cancer (P = .0043). Pathway analysis identified DNA double-strand break repair by homologous recombination (DSBR-HR) as a major pathway affecting susceptibility for gene methylation that was validated by measuring chromatid breaks in lymphocytes challenged by bleomycin. Conclusions: A functional 15q12 variant was identified as a risk factor for gene methylation and lung cancer. The associations could be mediated by GABAergic signaling that drives the smoking-induced mucous cell metaplasia. Our findings also substantiate DSBR-HR as a critical pathway driving epigenetic gene silencing.
- Subjects
LUNG cancer risk factors; CANCER-related mortality; TUMOR suppressor genes; SPUTUM; SMOKING; HEALTH
- Publication
JNCI: Journal of the National Cancer Institute, 2015, Vol 107, Issue 5, p1
- ISSN
0027-8874
- Publication type
Article
- DOI
10.1093/jnci/djv035