title: Aspirin use, 8q24 single nucleotide polymorphism rs6983267, and colorectal cancer according to CTNNB1 alterations.
abstract: BACKGROUND
  Regular aspirin use reduces the risk for colorectal cancer (CRC), possibly through inhibition of WNT/cadherin-associated protein β1 (CTNNB1 or β-catenin) signaling. The single nucleotide polymorphism (SNP) rs6983267 on chromosome 8q24 is a CRC susceptibility locus that affects binding activity of transcription factor 7 like-2 (TCF7L2) to CTNNB1, thereby altering expression of target oncogenes, including MYC.
  
  
  METHODS
  We evaluated regular aspirin use and CRC risk according to genotypes of SNP rs6983267 and CTNNB1 expression status in two prospective case-control studies (840 CRC case patients and 1686 age- and race-matched control subjects) nested within the Nurses' Health Study and the Health Professionals Follow-up Study. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression models. All statistical tests were two-sided.
  
  
  RESULTS
  A lower risk of CRC was associated with regular aspirin use and the T allele of rs6983267. The effect of aspirin was confined to individuals with protective T allele of rs6983267 (additive matching factors-adjusted OR for T allele = 0.83; 95% CI = 0.74 to 0.94; P trend = .002; P interaction = .01). Additionally, the T allele of rs6983267 was associated with a reduced expression of MYC oncogene (P trend = .03). Moreover, among individuals with protective T allele, the effect of regular aspirin use was limited to those with positive nuclear CTNNB1 expression. In a functional analysis, in vitro treatment of LS174T cells (a cell line heterozygous for rs6983267) with aspirin was statistically significantly associated with higher G/T allelic ratio of TCF7L2 immunoprecipitated DNA (P = .03).
  
  
  CONCLUSIONS
  Our results support an influence of aspirin on WNT/CTNNB1 signaling and suggest that aspirin chemoprevention may be tailored according to rs6983267 genotype.
authors: Affiliations of authors: Division of Cancer Epidemiology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD (HN); Channing Division of Network Medicine, Department of Medicine (HN, DJH, ELG, CSF, ATC) and Department of Epidemiology (DJH, PK, ELG, SO), Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Center for Molecular Oncologic Pathology (TM, YI, AK, MY, SO), Department of Medical Oncology (TM, MS, YI, AK, MY, CSF, SO, MLF), and Department of Biostatistics and Computational Biology (LW), Dana-Farber Cancer Institute, Boston, MA; Department of Epidemiology (DJH, ELG, SO) and Department of Nutrition, Harvard School of Public Health, Boston, MA (DJH, ELG); Broad Institute, Program in Medical and Population Genetics, Cambridge, MA (MLF); Division of Gastroenterology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (ATC).
authors: Hongmei
authors: H
authors: Nan
authors: Teppei
authors: T
authors: Morikawa
authors: Miia
authors: M
authors: Suuriniemi
authors: Yu
authors: Y
authors: Imamura
authors: Lillian
authors: L
authors: Werner
authors: Aya
authors: A
authors: Kuchiba
authors: Mai
authors: M
authors: Yamauchi
authors: David J
authors: DJ
authors: Hunter
authors: Peter
authors: P
authors: Kraft
authors: Edward L
authors: EL
authors: Giovannucci
authors: Charles S
authors: CS
authors: Fuchs
authors: Shuji
authors: S
authors: Ogino
authors: Matthew L
authors: ML
authors: Freedman
authors: Andrew T
authors: AT
authors: Chan
mesh_terms: D000328:Adult; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage; D016588:Anticarcinogenic Agents / Q000008:administration & dosage*; D001241:Aspirin / Q000008:administration & dosage*; D016022:Case-Control Studies; D047369:Chromatin Immunoprecipitation; D002898:Chromosomes, Human, Pair 8; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000517:prevention & control*; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D015398:Signal Transduction; D058118:Transcription Factor 7-Like 2 Protein / Q000378:metabolism; D051153:Wnt Proteins / Q000378:metabolism; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016588:Anticarcinogenic Agents; C495270:CTNNB1 protein, human; C544894:TCF7L2 protein, human; D058118:Transcription Factor 7-Like 2 Protein; D051153:Wnt Proteins; D051176:beta Catenin; D001241:Aspirin