Genetic associations with sporadic neuroendocrine tumor risk

Genetic risk factors for sporadic neuroendocrine tumors (NET) are poorly understood. We tested risk associations in patients with sporadic NET and non-cancer controls, using a custom array containing 1536 single-nucleotide polymorphisms (SNPs) in 355 candidate genes. We identified 18 SNPs associated with NET risk at a P-value < 0.01 in a discovery set of 261 cases and 319 controls. Two of these SNPs were found to be significantly associated with NET risk in an independent replication set of 235 cases and 113 controls, at a P value < 0.05. An SNP in interleukin 12A (IL12A rs2243123), a gene implicated in inflammatory response, replicated with an adjusted odds ratio (95% confidence interval) (aOR) = 1.47 (1.03, 2.11) P-trend = 0.04. A second SNP in defender against cell death, (DAD1 rs8005354), a gene that modulates apoptosis, replicated at aOR = 1.43 (1.02, 2.02) P-trend = 0.04. Consistent with our observations, a pathway analysis, performed in the discovery set, suggested that genetic variation in inflammatory pathways or apoptosis pathways is associated with NET risk. Our findings support further investigation of the potential role of IL12A and DAD1 in the etiology of NET.