Increased Expression of Long Non-coding RNA H19 is Associated With Colon Cancer Recurrence.

BACKGROUND: Colon cancer is a leading cause of cancer-related death. Long non-coding (Lnc) RNAs are critical mediators of tumor biology. H19 is a well-characterized lncRNA involved in p53 regulation and cancer progression. A specific colon cancer data set was utilized to determine if tumor H19 expression is associated with recurrence-free and overall survival. METHODS: Clinical patient data from The Cancer Genome Atlas colon adenocarcinoma data set was downloaded using FirebrowseR and normalized H19 expression from the associated RNA-seq data set downloaded using cBioportal. Univariable and multivariable Cox proportional regression analyses were used to identify an association between H19 expression in colon cancer tissue and recurrence-free, and overall survival. RESULTS: Three hundred eight patients were studied. Median age was 68 years (interquartile range: 58-77 years) and 156 patients (51%) were men. Increased H19 expression was associated with KRAS mutation status (P= 0.016). There was no difference in overall survival between the low and high H19 expression groups (log rank = 0.481); however, increased H19 expression was associated with reduced recurrence-free survival (Log-Rank = 0.012). On multivariable regression analysis, increased H19 expression (Hazard ratio  = 1.83, 95%CI: 1.02-3.27, P= 0.042), and stage III or IV disease (Hazard ratio  = 2.39, 95%CI: 1.34-4.27, P= 0.003) were risk factors for reduced recurrence-free survival. CONCLUSIONS: Colon cancer H19 expression is associated with advanced stage of tumor disease and is a significant risk factor for reduced recurrence-free survival. Tumor expression of H19 may have potential for both prognostic and therapeutic uses in the future.

Long non-coding RNA ZFAS1 is a major regulator of epithelial-mesenchymal transition through miR-200/ZEB1/E-cadherin, vimentin signaling in colon adenocarcinoma.

Colon adenocarcinoma is a common cause of cancer-related deaths worldwide. Epithelial-mesenchymal transition is a major regulator of cancer metastasis, and increased understanding of this process is essential to improve patient outcomes. Long non-coding RNA (lncRNA) are important regulators of carcinogenesis. To identify lncRNAs associated with colon carcinogenesis, we performed an exploratory differential gene expression analysis comparing paired colon adenocarcinoma and normal colon epithelium using an RNA-sequencing data set. This analysis identified lncRNA ZFAS1 as significantly increased in colon cancer compared to normal colon epithelium. This finding was validated in an institutional cohort using laser capture microdissection. ZFAS1 was also found to be principally located in the cellular cytoplasm. ZFAS1 knockdown was associated with decreased cellular proliferation, migration, and invasion in two colon cancer cell lines (HT29 and SW480). MicroRNA-200b and microRNA-200c (miR-200b and miR-200c) are experimentally validated targets of ZFAS1, and this interaction was confirmed using reciprocal gene knockdown. ZFAS1 knockdown regulated ZEB1 gene expression and downstream targets E-cadherin and vimentin. Knockdown of miR-200b or miR-200c reversed the effect of ZFAS1 knockdown in the ZEB1/E-cadherin, vimentin signaling cascade, and the effects of cellular migration and invasion, but not cellular proliferation. ZFAS1 knockdown was also associated with decreased tumor growth in an in vivo mouse model. These results demonstrate the critical importance of ZFAS1 as a regulator of the miR-200/ZEB1/E-cadherin, vimentin signaling cascade.

Crohn's disease-related single nucleotide polymorphisms are associated with ileal pouch afferent limb stenosis.

BACKGROUND: Ileal pouch-anal anastomosis (IPAA) is a common surgical treatment for ulcerative colitis. Afferent limb stenosis is an infrequent complication following IPAA, suggesting underlying Crohn's disease (CD). We hypothesized that CD-related single nucleotide polymorphisms (SNPs) are associated with afferent limb stenosis. METHODS: Afferent limb stenosis and CD control group patients were recruited from a prospective institutional inflammatory bowel disease database and associated biobank. Patient demographics, Montreal classification, and medication use were recorded. Ten SNPs associated with stricturing Crohn's disease were examined in genomic DNA and compared among afferent limb stenosis, stricturing CD, and non-stricturing CD controls. RESULTS: Twenty-seven afferent limb stenosis and 162 CD control group patients (108 stricturing, 54 non-stricturing) were identified. Patients were gender and race matched. Afferent limb stenosis and stricturing CD controls were younger at diagnosis (Montreal A1/A2 vs. A3) compared to non-stricturing CD controls (both p < 0.05). The majority of afferent limb stenosis patients were non-smokers compared to CD controls (74% vs. 36%, p < 0.01) and did not use biologic therapies (4% vs. 37%, p < 0.001). The FUT2 G allele was more frequent in afferent limb stenosis and stricturing CD controls compared to non-stricturing CD controls (both p < 0.05). The NOD2 T allele was more frequent in stricturing CD controls compared to afferent limb stenosis and non-stricturing CD controls (both p < 0.05). CONCLUSION: Afferent limb stenosis patients are phenotypically similar to stricturing CD controls, but differ with lower smoking rates and lower NOD2 allele frequency. Such differences could contribute to the presentation delay with a stricturing phenotype. Selective SNP assessment may help categorize patients likely to develop afferent limb stenosis.

Circulating plasma microRNAs in colorectal neoplasia: A pilot study in assessing response to therapy.

INTRODUCTION: Current serological surveillance markers to monitor colorectal cancer (CRC) or colorectal advanced adenomas (CAA) are hampered by poor sensitivity and specificity. The aim of this study is to identify and validate a panel of plasma microRNAs which change in expression after resection of such lesions. METHODS: A prospectively maintained colorectal surgery database was queried for patients in whom both pre- and post-procedural serum samples had been obtained. An initial screening analysis of CRC and CAA patients (5 each) was conducted using screening cards for 380 miRNAs. Four identified miRNAs were combined with a previously described panel of 7 miRNAs that were diagnostically predictive of CRC and CAA. Differential miRNA expression was assessed using quantitative real-time polymerase chain reaction(qRT-PCR). RESULTS: Fifty patients were included (n = 27 CRC, n = 23 CAA). There was no difference in age, gender, or race profile of CRC patients compared to CAA patients. Six miRNA were significantly increased after CRC resection (miR-324, let7b, miR-454, miR-374a, miR-122, miR-19b, all p<0.05), while three miRNAs were significantly increased following CAA resection (miR-454, miR-374a, miR-122, all p<0.05). Three miRNA were increased in common for both (miR-454, miR-374a, miR-122). DISCUSSION: The expression of miRNAs associated with neoplasia (either CRC or CAA) was significantly increased following surgical resection or endoscopic removal of CRC or CAA. Future studies should focus on the evaluation of these miRNAs in CRC and CAA prognosis.

Long non-coding RNA (lncRNA) and epithelial-mesenchymal transition (EMT) in colorectal cancer: a systematic review.

BACKGROUND: Colorectal cancer (CRC) is a leading cause of cancer-related death. Epithelial-mesenchymal transition (EMT) is a major process in tumor metastasis development. This systematic review aims to describe the role of long non-coding RNA (lncRNA) in EMT in CRC. METHODS: The electronic databases, PubMed, Cochrane, and EMBASE, were searched from January1990 to June 2019 to identify studies examining lncRNA and their role in mediating EMT in CRC. Studies examining clinical specimens and/or in vitro experiments were included. RESULTS: In 61 identified studies, 54 lncRNAs were increased in CRC compared to normal colorectal epithelium. Increased lncRNA expression was frequently associated with worse survival. Many lncRNAs mediate their effect through competitive endogenous RNA or transcription factor regulation. The ZEB1, 2/E-cadherin, Wnt/ß-catenin signaling, and chromatin remodeling pathways are discussed in particular. CONCLUSIONS: lncRNAs are major regulators of EMT and predictor adverse outcome in CRC patients. Future research must focus on delineating lncRNA function prior to potential clinical use.

Pyoderma Gangrenosum in Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: Pyoderma gangrenosum (PG) is an uncommon but severe extra-intestinal manifestation (EIM) of inflammatory bowel disease (IBD). The incidence and risk factors for PG are disputed. AIMS: To assess the incidence of PG and identify factors associated with PG in IBD patients. METHODS: A search of electronic databases (Ovid and PubMed) was conducted between 1966 and 2019. Studies that calculated the incidence of PG in IBD patient cohorts were included. Patient demographics, IBD subtype, and EIM presence were recorded. A review of our institutional database of 1057 IBD patients was conducted. A multivariate regression model and meta-analysis were conducted to identify risk factors for PG. A random effects model was used to combine the data of included studies. RESULTS: Fourteen studies were included in addition to 1057 IBD patients and 26 PG cases from the Louisville cohort. In total, there were 379 cases of PG in the cumulative cohort of 61,695 IBD patients. The PG incidence in individual studies ranged from 0.4 to 2.6%. In the institutional cohort, ocular EIMs and a permanent stoma were significant risk factors for PG. In the meta-analysis, PG was associated with female gender (RR = 1.328, 95% CI 1.161-1.520), Crohn's disease (RR = 1.193, 95% CI 1.001-1.422), erythema nodosum (RR = 9.281, 95% CI 6.081-14.164), and ocular EIM (RR = 4.55, 95% CI 3.04-6.81). There was study heterogeneity when assessing IBD subtype, ocular, and joint EIMs. CONCLUSIONS: There are conflicting data on the incidence and risk factors for PG. This meta-analysis confirms an association between PG and female gender, Crohn's disease, erythema nodosum, and ocular EIM that have been described in smaller studies.