Mucosal Microbiota from Colorectal Cancer, Adenoma and Normal Epithelium Reveals the Imprint of Fusobacterium nucleatum in Cancerogenesis.

An increasing amount of evidence suggests the emerging role of the gut microbiota in the development of colorectal cancer (CRC). This study aimed to elucidate the architecture of microbial communities within normal and neoplastic colonic mucosa. METHODS: Microbiota were analyzed by NGS and by an ensemble of metagenomics analysis tools in a total of 69 tissues from 9 patients with synchronous colorectal neoplasia and adenomas (27 specimens: 9 from normal tissues, 9 adenomas, and 9 tumours), 16 patients with only colonic adenomas (32 specimens: 16 from normal tissues and 16 adenomas), and from healthy subjects (10 specimens of normal mucosa). RESULTS: Weak differences were observed in alpha and beta metrics among the synchronous tissues from CRC and controls. Through pairwise differential abundance analyses of sample groups, an increasing trend of Rikenellaceae, Pseudomonas and Fusobacterium, and decreasing trends of Staphylococcus, Actinobacillus and Gemmiger were observed in CRC, while Staphylococcus and Bifidobacterium were decreased in patients with only adenomas. At RT-qPCR analysis, Fusobacterium nucleatum was significantly enriched in all the tissues of subjects with synchronous colorectal neoplasia. CONCLUSION: Our findings provide a comprehensive view of the human mucosa-associated gut microbiota, emphasizing global microbial diversity mostly in synchronous lesions and proving the constant presence of Fusobacterium nucleatum, with its ability to drive carcinogenesis.

Germline Alterations in Patients With IBD-associated Colorectal Cancer.

BACKGROUND: Patients with inflammatory bowel diseases (IBD), both ulcerative colitis (UC) and Crohn's disease (CD), are at risk of developing a colorectal cancer (CRC). No information is available on the contribution of patients' genetic background to CRC occurrence. This study investigates germline alterations in patients with IBD-associated CRC. METHODS: We profiled a panel of 39 genes potentially involved in cancer predisposition and searched for germline variants in IBD patients with CRC or high-grade dysplasia. RESULTS: After clinical exclusion of genetic cancer syndromes, 25 IBD patients (4 CD and 21 UC) with CRC or high-grade dysplasia were studied. After excluding variants with low likelihood of pathogenicity (classes 1 or 2 according the International Agency for Research on Cancer [IARC]), the panel identified pathogenic variants, likely pathogenic, or variants with unknown significance in 18 patients (72%). Six patients (24%) carried pathogenic or likely variants (IARC class 5 or 4). Of the identified variants, 4 encompassed the APC region, 3 the MLH1 gene, and the remaining ones the MSH2, MSH3, monoallelic MUTYH, EPCAM, BRCA1, CHEK2, POLD1, POLE, CDKN2A, and PDGFRA genes. Four patients carried at least 2 variants in different genes. Duration of IBD was significantly shorter in carriers of 4 or 5 IARC variants (7 years; range 0-21; P = .002) and in those with variants with unknown significance (12 years; range 0-22; P = .005) compared with patients without or with only benign variations (23.5 years; range 15-34). CONCLUSIONS: In silico analysis and sequence-based testing of germline DNA from IBD patients with CRC or high-grade dysplasia detected 24% of variants positioned in pathogenic classes. In patients with type 3, 4, and 5 variants, the onset of high-grade dysplasia or CRC was significantly earlier than in patients with benign or unidentified variants. The screening for these genes could identify IBD patients requiring a more intensive endoscopic surveillance for earlier detection of dysplastic changes.

Microbiome Analysis of Mucosal Ileoanal Pouch in Ulcerative Colitis Patients Revealed Impairment of the Pouches Immunometabolites.

The pathogenesis of ulcerative colitis (UC) is unknown, although genetic loci and altered gut microbiota have been implicated. Up to a third of patients with moderate to severe UC require proctocolectomy with ileal pouch ano-anastomosis (IPAA). We aimed to explore the mucosal microbiota of UC patients who underwent IPAA. METHODS: For microbiome analysis, mucosal specimens were collected from 34 IPAA individuals. Endoscopic and histological examinations of IPAA were normal in 21 cases, while pouchitis was in 13 patients. 19 specimens from the healthy control (10 from colonic and 9 from ileum) were also analyzed. Data were analyzed using an ensemble of software packages: QIIME2, coda-lasso, clr-lasso, PICRUSt2, and ALDEx2. RESULTS: IPAA specimens had significantly lower bacterial diversity as compared to normal. The microbial composition of the normal pouch was also decreased also when compared to pouchitis. Faecalibacterium prausnitzii, Gemmiger formicilis, Blautia obeum, Ruminococcus torques, Dorea formicigenerans, and an unknown species from Roseburia were the most uncommon in pouch/pouchitis, while an unknown species from Enterobacteriaceae was over-represented. Propionibacterium acnes and Enterobacteriaceae were the species most abundant in the pouchitis and in the normal pouch, respectively. Predicted metabolic pathways among the IPAA bacterial communities revealed an important role of immunometabolites such as SCFA, butyrate, and amino acids. CONCLUSIONS: Our findings showed specific bacterial signature hallmarks of dysbiosis and could represent bacterial biomarkers in IPAA patients useful to develop novel treatments in the future by modulating the gut microbiota through the administration of probiotic immunometabolites-producing bacterial strains and the addition of specific prebiotics and the faecal microbiota transplantation.

Impact of the COVID-19 outbreak and the serum prevalence of SARS-CoV-2 antibodies in patients with inflammatory bowel disease treated with biologic drugs.

BACKGROUND: Patients receiving biologic therapies are at risk for viral infections. This study investigated the impact of the SARS-CoV-2 infection and the serum prevalence of SARS-CoV-2 antibodies in patients with inflammatory bowel disease (IBD) treated with biologic drugs. METHODS: Information on demography, co-morbidities, clinical data regarding IBD, symptoms suggestive of the SARS-CoV-2 infection, close contacts with SARS-CoV-2 positive patients, hospitalization, and therapies administered for COVID-19 was collected for all patients who were being treated with biologic drugs. All patients underwent SARS-CoV-2 antibody testing. RESULTS: Two hundred and fifty-nine patients (27 children) with a mean age of 42.2 ±â€¯16.7 years (range 9 - 88) and a mean duration of disease of 13.4 ±â€¯10 years (range 0.2 - 49) were enrolled. One hundred four patients (40.2%) had ulcerative colitis, and 155 (59.8%) had Crohn's disease. About the therapy: 62 patients were receiving infliximab, 89 adalimumab, 20 golimumab, 57 vedolizumab, 27 ustekinumab, 1 thalidomide, and 3 an experimental compound. The mean Charlson Comorbidity Index was 2. Thirty-two patients (12.3%) reported respiratory symptoms, and 2 of them were hospitalized (0.77%). Two patients resulted positive for IgG against SARS-CoV-2 (0.77%). CONCLUSIONS: In patients with IBD, treatment with biologic drug does not represent a risk factor for the SARS-CoV-2 infection.

False-positive results of SARS-CoV-2 IgM/IgG antibody tests in sera stored before the 2020 pandemic in Italy.

OBJECTIVES: Aside from the outbreak of the coronavirus disease 2019 (COVID-19), serological tests are not well known for their diagnostic value. We assessed the performance of serological tests using stored sera from patients with a variety of pathologic conditions, collected before the 2020 pandemic in Italy. METHODS: Rapid lateral flow tests and Enzyme-Linked Immunosorbent Assays (ELISA) that detect Immunoglobulin M (IgM) and Immunoglobulin G (IgG) antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were carried out using 1150 stored human serum samples that had been collected in 2018 and 2019. The tests were also run using samples from 15 control patients who had positive or negative oral swab test results, as assessed using real-time reverse transcription-polymerase chain reaction (rRT-PCR). The urea dissociation test was employed to rule out false-positive reactivity in the two antibody detection methods. RESULTS: The lateral flow tests revealed 21 positive samples from the stored sera: 12 for IgM, four for IgG, and five for IgM/IgG. Among the nine rRT-PCR- positive controls, six individuals presented IgG and three IgM/IgG positivity. Using the urea (6 mol/L) dissociation test, two of the twelve stored samples that had shown IgM positivity were confirmed to be positive. The ELISA test detected four IgM-positive and three IgG-positive specimens. After treatment with 4 mol/L urea, the IgM-positive samples became negative, whereas the IgG positivity persisted. All of the rRT-PCR-positive controls were found to retain IgM or IgG positivity following the urea treatment. CONCLUSIONS: Our findings highlight the limited utility of serological testing for the SARS-CoV-2 virus based on the results of specimens collected before the outbreak of the infection.

microRNA-mRNA network model in patients with achalasia.

BACKGROUND: Achalasia is a rare idiopathic disease with a complex etio-pathogenesis still unknown. This study aimed to identify microRNA (miRNA)-mRNA regulatory networks underlying achalasia. METHODS: The investigation was performed in tissue specimens from 11 patients and five controls using the microarray technology followed by an integrated bioinformatics analysis. KEY RESULTS: One hundred and six miRNAs were significantly up-regulated and 64 were down-regulated in achalasia patients. The expression of the most 10 differential expressed miRNAs (miR-122-5p, miR-133a-3p, miR-504-5p, miR-187-3p, miR-133b, miR-200c-3p, miR-375, miR-200b-5p, miR-200b-3p, and miR203a) was confirmed by droplet digital PCR in an independent cohort. The interactions between the significant miRNAs and their targets uncovered 14 miRNA-mRNA interacting pairs with experimentally predicted genes (ie, FN1, ROCK2, DPYSL2), and 35 pairs with not experimentally target genes (ie, SULF1, MRVI1, PRKG1); all genes were involved in immune cell trafficking, skeletal and muscular system development, nervous system development macro-processes. CONCLUSION & INFERENCES: The mRNA-miRNA regulatory networks described in this study provide new insights in the genetic background of the disease, suggesting further investigations in novel pathogenic mechanisms.

Functional Implications of MicroRNAs in Crohn's Disease Revealed by Integrating MicroRNA and Messenger RNA Expression Profiling.

Crohn's disease (CD) is a debilitating inflammatory bowel disease (IBD) that emerges due to the influence of genetic and environmental factors. microRNAs (miRNAs) have been identified in the tissue and sera of IBD patients and may play an important role in the induction of IBD. Our study aimed to identify differentially expressed miRNAs and miRNAs with the ability to alter transcriptome activity by comparing inflamed tissue samples with their non-inflamed counterparts. We studied changes in miRNA-mRNA interactions associated with CD by examining their differential co-expression relative to normal mucosa from the same patients. Correlation changes between the two conditions were incorporated into scores of predefined gene sets to identify biological processes with altered miRNA-mediated control. Our study identified 28 miRNAs differentially expressed (p-values < 0.01), of which 14 are up-regulated. Notably, our differential co-expression analysis highlights microRNAs (i.e., miR-4284, miR-3194 and miR-21) that have known functional interactions with key mechanisms implicated in IBD. Most of these miRNAs cannot be detected by differential expression analysis that do not take into account miRNA-mRNA interactions. The identification of differential miRNA-mRNA co-expression patterns will facilitate the investigation of the miRNA-mediated molecular mechanisms underlying CD pathogenesis and could suggest novel drug targets for validation.

Crohn's Disease Localization Displays Different Predisposing Genetic Variants.

BACKGROUND: Crohn's disease (CD) is a pathologic condition with different clinical expressions that may reflect an interplay between genetics and environmental factors. Recently, it has been highlighted that three genetic markers, NOD2, MHC and MST1, were associated to distinct CD sites, supporting the concept that genetic variations may contribute to localize CD. Genetic markers, previously shown to be associated with inflammatory bowel disease (IBD), were tested in CD patients with the aim to better dissect the genetic relationship between ileal, ileocolonic and colonic CD and ascertain whether a different genetic background would support the three disease sites as independent entities. METHODS: A panel of 29 SNPs of 19 IBD loci were analyzed by TaqMan SNP allelic discrimination method both evaluating their distinct contribute and analyzing all markers jointly. RESULTS: Seven hundred and eight CD patients and 537 healthy controls were included in the study. Of the overall population of patients, 237 patients had an ileal involvement (L1), 171 a colonic localization (L2), and the 300 remaining an ileocolon location (L3). We confirmed the association for 23 of 29 variations (P < 0.05). Compared to healthy controls, 16 variations emerged as associated to an ileum disease, 7 with a colonic disease and 14 with an ileocolonic site (P < 0.05). Comparing ileum to colonic CD, 5 SNPs (17%) were differentially associated (P < 0.05). A genetic model score that aggregated the risks of 23 SNPs and their odds ratios (ORs), yielded an Area Under the Curve (AUC) of 0.70 for the overall CD patients. By analyzing each CD location, the AUC remained at the same level for the ileal and ileocolonic sites (0.73 and 0.72, respectively), but dropped to a 0,66 value in patients with colon localization. CONCLUSIONS: Our findings reaffirm the existence of at least three different subgroups of CD patients, with a genetic signature distinctive for the three main CD sites.

Inflammatory Bowel Disease Meets Systems Biology: A Multi-Omics Challenge and Frontier.

The inflammatory bowel disease (IBD) is a systemic disease that is characterized by the inflammation of the gastrointestinal tract. It includes ulcerative colitis and the Crohn's disease. Presently, IBD is one of the most investigated common complex human disorders, although its causes remain unclear. Multi-omics mechanisms involving genomic, transcriptomic, proteomic, and epigenomic variations, not to forget the miRNome, together with environmental contributions, result in an impairment of the immune system in persons with IBD. Such interactions at multiple levels of biology and in concert with the environment constitute the actual engine of this complex disease, demanding a multifactorial and multi-omics perspective to better understand the root causes of IBD. This expert analysis reviews and examines the latest literature and underscores, from the perspective of systems biology, the value of multi-omics technologies as opportunities to unravel the "IBD integrome." We anticipate that multi-omics research will accelerate the new discoveries and insights on IBD in the near future. It shall also pave the way for early diagnosis and help clinicians and families with IBD to forecast and make informed decisions about the prognosis and, possibly, personalized therapeutics in the future.

Gene expression of muscular and neuronal pathways is cooperatively dysregulated in patients with idiopathic achalasia.

Idiopathic achalasia is characterized by the absence of peristalsis secondary to loss of neurons in the myenteric plexus that hampers proper relaxation of the lower esophageal sphincter. Achalasia can be considered a multifactorial disorder as it occurs in related individuals and is associated with HLA class II genes, thereby suggesting genetic influence. We used microarray technology and advanced in-silico functional analyses to perform the first genome-wide expression profiling of mRNA in tissue samples from 12 achalasia and 5 control patients. It revealed 1,728 differentially expressed genes, of these, 837 (48.4%) were up-regulated in cases. In particular, genes participating to the smooth muscle contraction biological function were mostly up-regulated. Functional analysis revealed a significant enrichment of neuronal/muscular and neuronal/immunity processes. Upstream regulatory analysis of 180 genes involved in these processes suggested TLR4 and IL18 as critical key-players. Two functional gene networks were significantly over-represented: one involved in organ morphology, skeletal muscle system development and function, and neurological diseases, and the other participating in cell morphology, humoral immune response and cellular movement. These results highlight on pivotal genes that may play critical roles in neuronal/muscular and neuronal/immunity processes, and that may contribute to the onset and development of achalasia.

Systematic analysis of circadian genes using genome-wide cDNA microarrays in the inflammatory bowel disease transcriptome.

Simultaneous analysis of the transcripts of thousands of genes by cDNA microarrays allows the identification of genetic regulatory mechanisms involved in disease pathophysiology. The circadian clock circuitry controls essential cell processes and the functioning of organ systems, which are characterized by rhythmic variations with 24-hour periodicity. The derangement of these processes is involved in the basic mechanisms of inflammatory, metabolic, degenerative and neoplastic diseases. We evaluated by genome-wide cDNA microarray analysis the transcriptome of endoscopic mucosal biopsies of patients with inflammatory bowel diseases (IBD) focusing on the expression of circadian genes in Crohn's disease (CD) and ulcerative colitis (UC). Twenty-nine IBD patients (15 with CD and 14 with UC) were enrolled and mucosal biopsies were sampled at either inflamed or adjacent non-inflamed areas of the colon. A total of 150 circadian genes involved in pathways controlling crucial cell processes and tissue functions were investigated. In CD specimens 50 genes were differentially expressed, and 21 genes resulted up-regulated when compared to healthy colonic mucosa. In UC specimens 50 genes were differentially expressed, and 27 genes resulted up-regulated when compared to healthy colonic mucosa. Among the core clock genes ARNTL2 and RORA were up-regulated, while CSNK2B, NPAS2, PER1 and PER3 were down-regulated in CD specimens. Conversely, ARNTL2, CRY1, CSNK1E, RORA and TIPIN were up-regulated, while NR1D2 and PER3 were down-regulated in UC. In conclusion, in CD and UC patients there are differences in the expression of circadian genes between normal and diseased intestinal mucosa. The deregulated genes evidenced by transcriptome analysis in the major IBDs may play a crucial role in the pathophysiological mechanisms and may suggest novel therapeutic approaches.

Genome-wide Pathway Analysis Using Gene Expression Data of Colonic Mucosa in Patients with Inflammatory Bowel Disease.

BACKGROUND: Ulcerative colitis (UC) and Crohn's disease (CD) share some pathogenetic features. To provide new steps on the role of altered gene expression, and the involvement of gene networks, in the pathogenesis of these diseases, we performed a genome-wide analysis in 15 patients with CD and 14 patients with UC by comparing the RNA from inflamed and noninflamed colonic mucosa. METHODS: Two hundred ninety-eight differentially expressed genes in CD and 520 genes in UC were identified. By bioinformatic analyses, 34 pathways for CD, 6 of them enriched in noninflamed and 28 in inflamed tissues, and 19 pathways for UC, 17 in noninflamed and 2 in inflamed tissues, were also highlighted. RESULTS: In CD, the pathways included genes associated with cytokines and cytokine receptors connection, response to external stimuli, activation of cell proliferation or differentiation, cell migration, apoptosis, and immune regulation. In UC, the pathways were associated with genes related to metabolic and catabolic processes, biosynthesis and interconversion processes, leukocyte migration, regulation of cell proliferation, and epithelial-to-mesenchymal transition. CONCLUSIONS: In UC, the pattern of inflammation of colonic mucosa is due to a complex interaction network between host, gut microbiome, and diet, suggesting that bacterial products or endogenous synthetic/catabolic molecules contribute to impairment of the immune response, to breakdown of epithelial barrier, and to enhance the inflammatory process. In patients with CD, genes encoding a large variety of proteins, growth factors, cytokines, chemokines, and adhesion molecules may lead to uncontrolled inflammation with ensuing destruction of epithelial cells, inappropriate stimulation of antimicrobial and T cells differentiation, and inflammasome events.

Variation in genes encoding for interferon λ-3 and λ-4 in the prediction of HCV-1 treatment-induced viral clearance.

BACKGROUND & AIMS: In patients with chronic HCV-1 infection, recent evidences indicate that determination of a dinucleotide polymorphism (ss469415590, ΔG/TT) of a new gene, designated IFN λ-4, might be more accurate than the 12979860CC type of the IL28B locus in predicting sustained virological response (SVR) following peg-interferon and ribavirin. In addition, combined genotyping of different SNPs of the IL28B locus was shown to help dissect patients most prone to SVR among those with rs12979860CT. We examined whether single or combined genotyping of two IL28B SNPs, rs12979860 and rs8099917, and ss469415590 variation might improve the prediction of SVR. RESULTS: In the study cohort of 539 patients, 38% had SVR. The SNPs 12979860CC, rs8099917TT, and rs469415590TT/TT correlated significantly with SVR (68%, 50%, and 67%). Carriers of either the triplotype rs12979860CC_ss469415590TT/TT_rs8099917TT or the diplotype rs12979860CC_ss469415590TT/TT had the highest SVR rate (72%). In carriers of the rs12979860 T allele, neither the rs8099917 nor the ss469415590 improved the response prediction. After pooling this finding with data from previous studies, in rs12979860 T heterozygous individuals the co-presence of the rs8099917TT SNP was associated with improved response prediction. CONCLUSION: In HCV-1 patients, the rs12979860 polymorphism appeared as the hit SNP better predicting response following peg-interferon and ribavirin treatment. Additional ss469415590 or rs8099917 genotyping had no added benefit for response prediction. In the subset of carriers of the rs12979860 T allele, genotyping of the rs8099917 SNP was unhelpful in the present investigation, but may inform clinical prediction of treatment response when our data were pooled with previous investigations.

Impact of genetic polymorphisms on the pathogenesis of idiopathic achalasia: Association with IL33 gene variant.

AIM: To investigate the association of single nucleotide polymorphisms (SNPs) of genes involved in the regulation of immune responses, IL33, IL1RL1, IL23R, and IL10, with idiopathic achalasia in an Italian cohort of patients. MATERIALS AND METHODS: A panel of eleven polymorphisms were genotyped in 116 unrelated idiopathic achalasic patients and 371 healthy subjects, by using TaqMan genotyping assays. RESULTS: Significant differences of allele (P=0.0065, OR=1.59, CI=1.14-2.22) and genotype (P=0.0097, OR=1.74, CI=1.14-2.65) frequencies of the IL33 rs3939286 variant were found between achalasic patients and controls. No association of the other investigated SNPs was detected. No differences in genotype and allele distribution were found with respect to clinical characteristics of patients. CONCLUSION: We provide for the first time an association between the risk of developing idiopathic achalasia and IL-33 variant, underling the role of cytokines and inflammatory mediators on the pathogenesis of the disease.

Genetic variants of membrane metallopeptidase genes in inflammatory bowel diseases.

BACKGROUND: The substance P pathway modulates neuroimmune interactions during intestinal inflammation. AIMS: To analyse mucosal expression and genetic variants of the genes coding for substance P, neurokinin-1 receptor and neutral endopeptidase in patients with inflammatory bowel disease. METHODS: qRT-PCR was used to analyse mRNA levels in matched, paired samples of inflamed colonic mucosa and adjacent non-inflamed endoscopic tissue from 26 Crohn's disease and 25 ulcerative colitis patients. Allele and genotype frequencies of tag-SNPs were determined in 908 Crohn's disease, 929 ulcerative colitis, and 853 controls. Expression levels and genotype distributions were examined within patients' clinical sub-phenotypes. RESULTS: All 3 evaluated genes were overexpressed in inflamed tissues from Crohn's disease (P=0.033, P=4×10(-5), P=0.001), while in ulcerative colitis only higher levels of the gene coding for neutral endopeptidase were statistically significant (P=2.5×10(-5)). Smoking habit and perianal disease were significantly associated with substance P (P=0.002) and neurokinin-1 receptor levels (P=0.02) in Crohn's disease. Neutral endopeptidase rs701109 variant was associated with inflammatory bowel disease (Crohn's disease: P=0.022; ulcerative colitis: P=0.045), and with the need for colectomy in ulcerative colitis (P=0.008, OR=2.46, 95% CI=1.27-4.76). CONCLUSIONS: Genetic variants of the gene coding for neutral endopeptidase might affect the neuroimmune interaction during intestinal inflammation and influence clinical sub-phenotypes in patients with inflammatory bowel disease.

Associations between genetic polymorphisms in IL-33, IL1R1 and risk for inflammatory bowel disease.

BACKGROUND: Recent evidence suggests that the IL-33/IL1RL1 axis plays a critical role in several autoimmune and inflammatory disorders; however, its mechanistic role in inflammatory bowel disease (IBD) has not been clearly defined. We investigated the contribution of IL-33 and IL1RL1 polymorphisms to IBD risk, and possible correlations with phenotype in an Italian cohort of adult and pediatric patients. METHODS: We evaluated the association of six SNPs in IL-33 and IL1RL1 genes, in 805 Crohn's disease (CD), 816 ulcerative colitis (UC), and 752 controls, using Taqman. IL-33 and IL1RL1 mRNA expression was also analyzed. RESULTS: Significant allele and genotype associations with IL-33 rs3939286 were found in CD (P = 0.004; P = 0.035) and UC patients (P = 0.002; P = 0.038). After stratifying the cohort for age at diagnosis, the differences remained significant only in the IBD adult-onset. Significant associations were also obtained in CD patients with two IL1RL1 polymorphisms (rs13015714 and rs2058660, P<0.015). By combining homo- and heterozygous carriers of the rs13015714 risk allele, differences were still significant for both CD adult- and pediatric-onset. Upon genotype-phenotype evaluation, an increased frequency of extensive colitis in adult UC (P = 0.019) and in steroid-responsive pediatric patients (P = 0.024) carrying the IL-33 rs3939286 risk genotype, was observed. mRNA expression of IL-33 and IL1RL1 in inflamed IBD biopsy samples was significantly increased. CONCLUSIONS: Common IL-33 and IL1RL1 polymorphisms contribute to the risk of IBD in an Italian cohort of adult and pediatric patients, with some influence on sub-phenotypes.

Association study of a polymorphism in clock gene PERIOD3 and risk of inflammatory bowel disease.

Altered body rhythmicity and deregulated clock gene expression may cause circadian disruption, which can lead to immune dysregulation and chronic inflammatory diseases. PERIOD3 (PER3) polymorphisms have been associated with circadian disruption and changed secretion of cytokines involved in chronic inflammation. Crohn's disease (CD) and ulcerative colitis (UC) are multifactorial diseases resulting from complex interaction among environmental/microbial factors and the intestinal immune system, triggering an abnormal immune response in genetically susceptible individuals. We evaluated the influence of a polymorphism of the clock gene PER3 on susceptibility and behavior of these inflammatory bowel diseases. The rs2797685 variant of the PER3 gene was assessed in 1082 CD and 972 UC patients, 754 of whom had been diagnosed <18 yrs of age, and 1311 unrelated healthy controls. Allele and genotype frequencies of rs2797685 were significantly increased in both CD (p = 1.6 × 10(-4), odds ratio [OR] = 1.38, 95% confidence interval [CI]: 1.17-1.63) and UC (p = .012, OR = 1.25, 95% CI: 1.05-1.48) patients. Difference between frequency distributions remained statistically significant after stratifying the cohort according to age at diagnosis for CD, but not for UC. Statistically significant association was found between PER3 polymorphism and use of immunosuppressive drugs in pediatric CD patients (p < .001) and with stricturing and fistulizing disease behavior in adult CD patients (p = .031). In conclusion, results of this association study suggest a possible role of PER3 polymorphism in determining susceptibility to CD and UC and phenotypic characteristics of CD. In particular, the rs2797685 variant of the PER3 gene is associated with a more aggressive form of CD, highlighted by higher use of immunosuppressants and more frequent stricturing and fistulizing disease behaviors, as well as early onset of CD. This is a descriptive study, and functional data are needed to prove a causal relationship; nonetheless, involvement of the clock gene machinery in the susceptibility and the behavior of inflammatory bowel diseases may suggest new pathophysiological mechanisms and new therapeutic approaches.

Investigation of multiple susceptibility loci for inflammatory bowel disease in an Italian cohort of patients.

BACKGROUND: Recent GWAs and meta-analyses have outlined about 100 susceptibility genes/loci for inflammatory bowel diseases (IBD). In this study we aimed to investigate the influence of SNPs tagging the genes/loci PTGER4, TNFSF15, NKX2-3, ZNF365, IFNG, PTPN2, PSMG1, and HLA in a large pediatric- and adult-onset IBD Italian cohort. METHODS: Eight SNPs were assessed in 1,070 Crohn's disease (CD), 1,213 ulcerative colitis (UC), 557 of whom being diagnosed at the age of ≤16 years, and 789 healthy controls. Correlations with sub-phenotypes and major variants of NOD2 gene were investigated. RESULTS: The SNPs tagging the TNFSF15, NKX2-3, ZNF365, and PTPN2 genes were associated with CD (P values ranging from 0.037 to 7×10(-6)). The SNPs tagging the PTGER4, NKX2-3, ZNF365, IFNG, PSMG1, and HLA area were associated with UC (P values 0.047 to 4×10(-5)). In the pediatric cohort the associations of TNFSF15, NKX2-3 with CD, and PTGER4, NKX2-3, ZNF365, IFNG, PSMG1 with UC, were confirmed. Association with TNFSF15 and pediatric UC was also reported. A correlation with NKX2-3 and need for surgery (P  =  0.038), and with HLA and steroid-responsiveness (P  =  0.024) in UC patients was observed. Moreover, significant association in our CD cohort with TNFSF15 SNP and colonic involvement (P  =  0.021), and with ZNF365 and ileal location (P  =  0.024) was demonstrated. CONCLUSIONS: We confirmed in a large Italian cohort the associations with CD and UC of newly identified genes, both in adult and pediatric cohort of patients, with some influence on sub-phenotypes.

Variants at the 3p21 locus influence susceptibility and phenotype both in adults and early-onset patients with inflammatory bowel disease.

BACKGROUND: To date, a number of high-profile studies have yielded over 50 inflammatory bowel disease (IBD) disease genes/loci. The polymorphisms rs9858542 (BSN) and rs3197999 (MST1), on 3p21 locus, have been found associated with susceptibility to IBD. We aimed to replicate these associations in adult and early-onset cohorts of IBD Italian patients, by analyzing also potential gene-gene interactions with variants in NOD2/CARD15, IL23R, ATG16L1, and IRGM genes, and investigating genotype-phenotype correlation. METHODS: In all, 1808 patients with IBD, 855 with Crohn's disease (CD) and 953 with ulcerative colitis (UC), including 539 patients with their initial diagnosis <19 years of age, and 651 controls were analyzed for SNPs rs9858542 and rs3197999. RESULTS: BSN and MST1 were significantly associated with either CD (P(rs9858542) 2.5 x 10(-7); P(rs3197999) 3.9 x 10(-7)), and UC (P(rs9858542) = 3.1 x 10(-4); P(rs3197999) = 8 x 10(-4)). Prevalence of these variants was significantly increased in both adult and early-onset IBD patients. After stepwise logistic regression, the 2 variants were associated in adult UC with distal colitis (P(rs9858542) = 0.013, odds ratio [OR] = 2.04, 95% confidence interval [CI] = 1.16-3.59; P(rs3197999) = 0.018, OR 1.9, 95% CI 1.2-3.3), while the rs3197999 variant was inversely associated with occurrence of extraintestinal manifestations in adult CD(P = 0.017, OR 0.6, 95% CI 0.4-0.9). CONCLUSIONS: We confirmed the association of BSN and MST1 with IBD susceptibility, either in the adult or the early-onset cohorts. These variants appeared to influence either the distal location of the disease in the UC cohort and extraintestinal manifestations in CD patients.