Abstract
PURPOSE: The deleted-in-polyposis1-like1 (DP1L1) gene displays pro-apoptotic activity and was proposed to be a tumor suppressor. It locates on chromosome 19p13.3, which harbors the locus for Peutz-Jeghers-Syndrome and is deleted in various tumors. We analyzed the association of DP1L1 polymorphisms with colon cancer, and cancer-associated Ulcerative colitis and Crohn's disease. EXPERIMENTAL DESIGN: Fifty-eight patients with colon cancer, 18 with Ulcerative colitis, 18 with Crohn's disease, and 70 control individuals were genotyped for SNPs at positions 992 and 996 of DP1L1 cDNA. RESULTS: Homozygous carriers of 992A alleles comprised 16% of the control group but were significantly increased in colon cancer with a frequency of 36% (P = 0.013 cancer vs control). Homozygous 991-A was also elevated in Ulcerative colitis (N = 18) with a frequency of 33%. In contrast, 18 patients with Crohn's disease showed no difference in frequency of 992AA (22%) compared to control. The A-allele of the adjacent C996A polymorphism has a low frequency (3.5%) in the control population, but significantly increased frequency of 13% in colon cancer (P = 0.0149 for allele frequency, Fisher's exact). 996-A allele frequency is also increased in inflammatory bowel disease (IBD): 22% of Ulcerative colitis- and 50% of Crohn's disease-patients were heterozygous carriers of 996-A (P = 0.052 for CU and P < 0.0001 for MC vs controls). CONCLUSIONS: DP1L1 polymorphisms are associated with colon cancer and IBD. This indicates that DP1L1 plays a functional role in these conditions. Thus DP1L1 may be a diagnostic and therapeutic target for colon cancer and IBD.