Abstract 3750: Body mass index and obesity- and diabetes-associated genotypes and risk for pancreatic cancer

Abstract

Abstract Background: There is accumulating evidence that obesity and diabetes are modifiable risk factors for pancreatic cancer. However, the genetic factors predispose individuals with obesity or diabetes to pancreatic cancer has not been identified. Aims: To investigate the hypothesis that obesity- and diabetes-related genes modify the risk of pancreatic cancer. Methods: We genotyped 15 single nucleotide polymorphisms (SNPs) of the fat mass and obesity associated (FTO), peroxisome proliferators-activated receptor gamma (PPARγ), nuclear receptor family 5 member 2 NR5A2 (aka liver receptor homolog 1), AMP-activated protein kinase (AMPK), and adiponectin (ADIPOQ) gene in 1,070 patients with pancreatic cancer and 1,175 cancer-free controls that are enrolled in a case control study conducted at MD Anderson Cancer Center during 2000-2008. Information on risk factors was collected by personal interview. Genotypes were determined using the Taqman method. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were calculated using multivariable unconditional logistic regression. Results: The PPARγ P12A (rs1801282) GG genotype was inversely associated with risk of pancreatic cancer (AOR: 0.21, 95%CI: 0.07−0.62). Three NR5A2 variants (rs12029406, rs3790844 and rs3790843) that were previously identified in a genome-wide association study were significantly associated with reduced risk of pancreatic cancer, AORs ranging 0.57-0.79. Two FTO gene variants (rs8050136 and rs9939609) and one ADIPOQ variant (rs17366743) were differentially associated with pancreatic cancer according to levels of body mass index (BMI) (P interaction = 0.0001, 0.0015, and 0.03). The variant alleles were associated reduced risk of pancreatic cancer among individuals with normal weight but increased risk among those with excess body weight. For example, the AOR (95%CI) for FTO IVS1-2777 AC/AA genotype (rs8050136) was 0.72 (0.55-0.96) and 1.54 (1.14-2.09) in participants with a BMI <25 or ≥ 25 kg/m2, respectively. We observed no significant association between AMPK genotype and pancreatic cancer and no genotype interactions with diabetes or smoking. Conclusion: Our findings suggest a protective effect of PPARγ P12A GG genotype and NR5A2 variants on pancreatic cancer. A positive association of FTO and ADIPOQ gene variants with pancreatic cancer may be limited to persons who are overweight. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3750. doi:10.1158/1538-7445.AM2011-3750