Purpose Patients with ulcerative colitis (UC) are at increased risk for colorectal cancer, although mechanisms underlying neoplastic transformation are poorly understood. We sought to evaluate the role of microRNAs in neoplasia development in this high-risk population. Experimental Design Tissue from 12 controls, 9 UC patients without neoplasia, and 11 UC patients with neoplasia was analyzed. miRNA array analysis was performed and select miRNAs assayed by real-time PCR on the discovery cohort and a validation cohort. DNA methylation of miR-193a was assessed. Following transfection of miR-193a-3p, proliferation, IL17RD expression, and luciferase activity of the 3’UTR of IL17RD were measured. Tumor growth in xenografts as well as EGFR signaling were assessed in HCT116 cells expressing IL17RD with either a mutant 3’ untranslated region (UTR) or wild-type (WT) 3’UTR. Results miR-31, miR-34a, miR-106b, and miR-193a-3p were significantly dysregulated in UC-neoplasia and adjacent tissue. Significant down-regulation of miR-193a-3p was also seen in an independent cohort of UC-cancers. Changes in methylation of miR-193a or expression of pri-miR-193a were not observed in UC-cancer. Transfection of miR-193a-3p resulted in decreased proliferation, and identified IL17RD as a direct target of miR-193a-3p. IL17RD expression was increased in UC-cancers, and miR-193a-3p treatment decreased growth and EGFR signaling of HCT116 cells in xenografts expressing both IL17RD with WT 3’UTR compared to cells expressing IL17RD with mutant 3’UTR. Conclusions miR-193a-3p is down-regulated in UC-neoplasia, and its loss promotes carcinogenesis through up-regulation of IL17RD. These findings provide novel insight into inflammation-driven CRC and could suggest new therapeutic targets in this high-risk population.

Purpose Epidermal growth factor receptors (EGFR) are required for tumor promotion by Western diet (WD). The metalloprotease, ADAM17 activates EGFR by releasing pro-EGFR ligands. ADAM17 is regulated by G-protein coupled receptors, including CXCR4. Here we investigated CXCR4-ADAM17 crosstalk and examined the role of ADAM17 in tumorigenesis. Experimental Design We used CXCR4 inhibitor, AMD3100 and ADAM17 inhibitor, BMS566394 to assess CXCR4-ADAM17 crosstalk in colon cancer cells. We compared expression of CXCR4 ligand, CXCL2, and ADAM17 in mice fed WD versus standard diet. Separately, mice were treated with marimastat, a broad-spectrum ADAM17 inhibitor, or AMD3100 to assess EGFR activation by ADAM17 and CXCR4. Using Apc mutant Min mice, we investigated effects of ADAM17/10 inhibitor INCB3619 on tumorigenesis. To assess effects of colonocyte ADAM17, mice with ADAM17 conditional deletion were treated with azoxymethane (AOM). ADAM17 expression was also compared in colonocytes from primary human colon cancers and adjacent mucosa. Results CXCL12 treatment activated colon cancer cell EGFR signals, and CXCR4 or ADAM17 blockade reduced this activation. In vivo, WD increased CXCL12 in stromal cells and TGFα in colonocytes. Marimastat or AMD3100 caused >50% reduction in EGFR signals (p<0.05). In Min mice, INCB3619 reduced EGFR signals in adenomas and inhibited intestinal tumor multiplicity (p<0.05). In the AOM model, colonocyte ADAM17 deletion reduced EGFR signals and colonic tumor development (p<0.05). Finally, ADAM17 was up-regulated >2.5-fold in human malignant colonocytes. Conclusions ADAM17 is a WD-inducible enzyme activated by CXCL12-CXCR4 signaling, suggesting the pathway: Western diet->CXCL12->CXCR4->ADAM17->TGFα‐>EGFR. ADAM17 might serve as a druggable target in chemoprevention strategies.

Background and Objectives: EUS-guided drainage of pancreatic fluid collections (PFCs) has been increasingly performed using lumen-apposing metal stents (LAMS). However, recent data have suggested higher adverse event rates with LAMS compared to double pigtail plastic stents (DPS) alone. To decrease risks, there has been anecdotal use of placing DPS through the LAMS. We aimed to determine whether the placement of DPS through cautery-enhanced LAMS at time of initial placement decreases adverse events or need for reintervention. Methods: We performed a multicenter retrospective study between January 2015 and October 2017 examining patients who underwent EUS-guided drainage of pseudocysts (PP), walled-off necrosis (WON), and postsurgical fluid collection using a cautery enhanced LAMS with and without DPS. Results: There were 68 patients identified at 3 US tertiary referral centers: 44 PP (65%), 17 WON (25%), and 7 PFSC (10%). There were 35 patients with DPS placed through LAMS (Group 1) and 33 with LAMS alone (Group 2). Overall technical success was 100%, clinical success was 94%, and adverse events (bleeding, perforation, stent occlusion, and stent migration) occurred in 28% of patients. Subgroup analysis compared specific types of PFCs and occurrence of adverse events between each group with no significant difference detected in adverse event or reintervention rates. Conclusion: This multicenter study of various types of PFCs requiring EUS-guided drainage demonstrates that deployment of DPS across cautery-enhanced LAMS at the time of initial drainage does not have a significant effect on clinical outcomes, adverse events, or need for reinterventions.

Abstract Background and Aims As ulcerative colitis [UC]-associated colorectal cancer [CRC] and sporadic CRC differ in presentation and molecular features, we sought to evaluate differences in the impact of DNA methylation on gene expression. Methods DNA methylation was assessed in 11 UC-CRCs and adjacent tissue and 11 sporadic CRCs and adjacent tissue, using Illumina arrays. RNA sequencing was performed on 10 UC-CRCs and adjacent tissue and eight sporadic CRCs and adjacent tissues. Differences in DNA methylation and transcript expression, as well as their correlation in the same tissues, were assessed. Immunohistochemistry was performed for three proteins, ANPEP, FAM92A1, and STK31, all of which exhibited an inverse correlation between DNA methylation and transcript expression in UC. Results Thirty three loci demonstrated differences in DNA methylation between UC-CRC and adjacent tissue. In contrast, there were 4204 differentially methylated loci between sporadic colon cancer and adjacent tissue. Eight hundred eighty six genes as well as 10 long non-coding RNAs [lncRNA] were differentially expressed between UC-CRC and adjacent tissues. Although there were no differentially methylated loci between UC and sporadic CRC, 997 genes and 38 lncRNAs were differentially expressed between UC-CRC and sporadic CRC. In UC, 18 genes demonstrated a negative correlation between DNA methylation and transcript expression. Evaluation of protein expression related to three genes, ANPEP, FAM92A1, and STK31, confirmed down-regulation of ANPEP and up-regulation of STK31 in UC-CRC. Conclusions Regulation of transcript expression by DNA methylation involves genes key to colon carcinogenesis and may account for differences in presentation and outcomes between inflammatory bowel disease and sporadic colon cancer.

Colorectal cancer is a leading cause of cancer deaths. The renin-angiotensin system (RAS) is upregulated in colorectal cancer, and epidemiologic studies suggest RAS inhibitors reduce cancer risk. Because vitamin D (VD) receptor negatively regulates renin, we examined anticancer efficacy of VD and losartan (L), an angiotensin receptor blocker. Control Apc þ/LoxP mice and tumor-forming Apc þ/LoxP Cdx2P-Cre mice were randomized to unsupplemented Western diet (UN), or diets supplemented with VD, L, or VDþL, the latter to assess additive or synergistic effects. At 6 months, mice were killed. Plasma Ca 2þ , 25(OH)D3, 1a, 25(OH) 2D3, renin, and angiotensin II (Ang II) were quantified. Colonic transcripts were assessed by qPCR and proteins by immunostaining and blotting. Cancer incidence and tumor burden were significantly lower in Creþ VD and Creþ L, but not in the Creþ VDþL group. In Apc þ/LoxP mice, VD increased plasma 1,25 (OH)2D3 and colonic VDR. In Apc þ/LoxP-Cdx2P-Cre mice, plasma renin and Ang II, and colonic tumor AT1, AT2, and Cyp27B1 were increased and VDR downregulated. L increased, whereas VD decreased plasma renin and Ang II in Creþ mice. VD or L inhibited tumor development, while exerting differential effects on plasma VD metabolites and RAS components. We speculate that AT1 is critical for tumor development, whereas RAS suppression plays a key role in VD chemoprevention. When combined with L, VD no longer increases active VD and colonic VDR in Cremice nor suppresses renin and Ang II in Creþ mice, likely contributing to lack of chemopreventive efficacy of the combination.