IMMUNOREACT 7: Regular aspirin use is associated with immune surveillance activation in colorectal cancer.

BACKGROUND: Long-term daily use of aspirin reduces incidence and mortality due to colorectal cancer (CRC). This study aimed to analyze the effect of aspirin on the tumor microenvironment, systemic immunity, and on the healthy mucosa surrounding cancer. METHODS: Patients with a diagnosis of CRC operated on from 2015 to 2019 were retrospectively analyzed (METACCRE cohort). Expression of mRNA of immune surveillance-related genes (PD-L1, CD80, CD86, HLA I, and HLA II) in CRC primary cells treated with aspirin were extracted from Gene Expression Omnibus-deposited public database (GSE76583). The experiment was replicated in cell lines. The mucosal immune microenvironment of a subgroup of patients participating in the IMMUNOREACT1 (ClinicalTrials.gov NCT04915326) project was analyzed with immunohistochemistry and flow cytometry. RESULTS: In the METACCRE Cohort, 12% of 238 patients analyzed were aspirin users. Nodal metastasis was significantly less frequent (p = .008) and tumor-infiltrating lymphocyte infiltration was higher (p = .02) among aspirin users. In the CRC primary cells and selected cell lines, CD80 mRNA expression was increased following aspirin treatment (p = .001). In the healthy mucosa surrounding rectal cancer, the ratio of CD8/CD3 and epithelial cells expressing CD80 was higher in aspirin users (p = .027 and p = .034, respectively). CONCLUSIONS: These data suggested that regular aspirin use may have an active role in enhancing immunosurveillance against CRC.

Innate Immunity Activation in Newly Diagnosed Ileocolonic Crohn's Disease: A Cohort Study.

BACKGROUND: Recent studies showed that early surgery for Crohn's disease leads to a lower recurrence rate. However, the underlying mechanism is unknown. OBJECTIVE: The study aims to analyze the innate immunity microenvironment in ileal mucosa according to the duration of Crohn's disease. DESIGN: A prospective cohort study. SETTINGS: Tertiary referral center for IBD surgery. PATIENTS: A total of 88 consecutive patients with Crohn's disease undergoing ileocolonic resection were prospectively enrolled. Mucosal samples were obtained from both healthy and inflamed ileum. Data from a public data set were analyzed as an external validation cohort. MAIN OUTCOME MEASURES: Neutrophil infiltration was evaluated by histological asessment and macrophage subpopulation was assessed by immunohistochemistry. Expressions of TLR2 , TLR4 , TLR5 , DEFB1 , DEFB4A , DEFB103 , DEFA5 , and DEFA6 were quantified by real-time quantitative polymerase chain reaction. Concentrations of BDNF, CCL-11, ICAM-1, IL-1A, IL-1ß, IL-1RN, IL-12p40, IL-12p70, IL-15, IL-17A, IL-23A, MMP-3, CCL-3, KITLG, and VEGFA were determined with an immunometric assay. RESULTS: Neutrophil infiltration is inversely correlated with disease duration. DEFB4A mRNA expression tended to be higher in late-stage Crohn's disease ( p = 0.07). A higher number of macrophages expressed CD163 at low intensity in late-stage Crohn's disease ( p = 0.04). The concentration of IL-15 ( p = 0.02) and IL-23A ( p = 0.05) was higher in healthy ileal mucosa of early-stage patients. In the external cohort, expressions of DEFB1 ( p = 0.03), DEFB4A ( p = 0.01), IL-2 ( p = 0.04), and IL-3 ( p = 0.03) increased in patients with late-stage Crohn's disease. LIMITATIONS: A relatively small number of patients, especially in the newly diagnosed group. CONCLUSIONS: In newly diagnosed Crohn's disease, high levels of IL-15 and IL-23 in healthy mucosa suggest that innate immunity is the starter of acute inflammation. Moreover, M2 macrophages increase in the healthy mucosa of patients with late-stage Crohn's disease, suggesting that reparative and profibrotic processes are predominant in the long term, and in this phase, anti-inflammatory therapy may be less efficient. See Video Abstract . ACTIVACIN DE LA INMUNIDAD INNATA EN LA RECIENTEMENTE DIAGNOSTICADA ENFERMEDAD DE CROHN ILEOCLICA UN ESTUDIO DE COHORTE: ANTECEDENTES:Estudios recientes demostraron que la cirugía temprana para la enfermedad de Crohn (EC) conduce a una menor tasa de recurrencia. Sin embargo, se desconoce el mecanismo subyacente.OBJETIVO:El estudio tiene como objetivo analizar el microambiente de la inmunidad innata en la mucosa ileal según la duración de la EC.DISEÑO:Un estudio de cohorte prospectivo.AJUSTES:Centro terciario de referencia para cirugía de EII.PACIENTES:Fueron registrados de manera prospectiva y consecutiva 88 pacientes con EC sometidos a resección ileocolónica. Se obtuvieron muestras de mucosa ileal, tanto del íleon sano como del íleon inflamado. Los datos se analizaron como una cohorte de validación externa.PRINCIPALES MEDIDAS DE RESULTADO:Fueron evaluados la infiltración de neutrófilos por histología y la subpoblación de macrófagos por inmunohistoquímica. La expresión de TLR2, TLR4, TLR5, DEFB1, DEFB4A, DEFB103, DEFA5 y DEFA6 fueron cuantificados mediante qPCR en tiempo real. Las concentraciones de BDNF, CCL-11, ICAM-1, IL-1A, IL-1B, IL-1RN, IL-12 p40, IL-12 p70, IL-15, IL-17A, IL-23A, MMP-3, CCL-3, KITLG, VEGFA se determinaron con ensayo inmunométrico.RESULTADOS:La infiltración de neutrófilos se correlaciona inversamente con la duración de la enfermedad. La expresión del ARNm de DEFB4A mostro una tendencia a ser mayor en la EC en etapa tardía ( p = 0,07). Un mayor número de macrófagos expresaron CD163 a baja intensidad en la etapa tardía ( p = 0,04). La concentración de IL15 ( p = 0,02) e IL23A ( p = 0,05) fue mayor en la mucosa ileal sana de pacientes en estadio temprano. En la cohorte externa, la expresión de DEFB1 ( p = 0,03) y DEFB4A ( p = 0,01), IL2 ( p = 0,04) e IL3 ( p = 0,03) aumentó en pacientes en etapa tardía.LIMITACIONES:Un número relativamente pequeño de pacientes, especialmente en el grupo recién diagnosticado.CONCLUSIONES:En la EC recién diagnosticada, los altos niveles de IL-15 e IL-23 en la mucosa sana sugieren que la inmunidad innata es el promotor de la inflamación aguda. Además, los macrófagos M2 aumentan en la mucosa sana de pacientes con EC en etapa tardía, lo que sugiere que los procesos reparadores y profibróticos son predominantes a largo plazo y en esta fase, la terapia antiinflamatoria puede ser menos eficiente. (Traducción-Dr. Osvaldo Gauto ).

Collagen VI promotes recovery from colitis by inducing lymphangiogenesis and drainage of inflammatory cells.

Despite a number of studies providing evidence that the extracellular matrix (ECM) is an active player in the pathogenesis of intestinal inflammation, knowledge on the actual contribution of specific ECM molecules in the progression of inflammatory bowel disease (IBD) remains scant. Here, we investigated the role of a major ECM protein, collagen VI (ColVI), in gut homeostasis and elucidated the impact of its deregulation on the pathophysiology of IBD. To this end, we combined in vivo and ex vivo studies on wild type and ColVI-deficient (Col6a1-/- ) mice both under physiological conditions and during experimentally induced acute colitis and its subsequent recovery, by means of gut histology and immunostaining, gene expression, bone marrow transplantation, flow cytometry of immune cell subpopulations, and lymph flow assessment. We found that ColVI displayed dynamic expression and ECM deposition during the acute inflammatory and recovery phases of experimentally induced colitis, whereas the genetic ablation of ColVI in Col6a1 null mice impaired the functionality of lymphatic vessels, which in turn affected the resolution of inflammation during colitis. Based on these findings, we investigated ColVI expression and deposition in ileal specimens from two cohorts of patients affected by Crohn's disease (CD) and correlated ColVI abundance to clinical outcome. Our results show that high ColVI immunoreactivity in ileal biopsies of CD patients at diagnosis correlates with increased risk of surgery and that ColVI expression in biopsies taken at the resection margin during surgery, and showing inactive disease, predict disease recurrence. Our data unveil a key role for ColVI in the intestinal microenvironment, where it is involved in lymphangiogenesis and intestinal inflammation. Altogether, these findings point at the dysregulation of ColVI expression as a novel factor contributing to the onset and maintenance of inflammation in CD via mechanisms impinging on the modulation of inflammatory cell recruitment and function. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

IMMUNOREACT 6: weak immune surveillance characterizes early-onset rectal cancer.

BACKGROUND: Colon cancer in young patients is often associated with hereditary syndromes; however, in early-onset rectal cancer, mutations of these genes are rarely observed. The aim of this study was to analyse the features of the local immune microenvironment and the mutational pattern in early-onset rectal cancer. METHODS: Commonly mutated genes were analysed within a rectal cancer series from the University Hospital of Padova. Mutation frequency and immune gene expression in a cohort from The Cancer Genome Atlas ('TCGA') were compared and immune-cell infiltration levels in the healthy rectal mucosa adjacent to rectal cancers were evaluated in the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 ('IMMUNOREACT') series. RESULTS: In the authors' series, the mutation frequency of BRAF, KRAS, and NRAS, as well as microsatellite instability frequency, were not different between early- and late-onset rectal cancer. In The Cancer Genome Atlas series, among the genes with the most considerable difference in mutation frequency between young and older patients, seven genes are involved in the immune response and CD69, CD3, and CD8ß expression was lower in early-onset rectal cancer. In the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 series, young patients had a lower rate of CD4+ T cells, but higher T regulator infiltration in the rectal mucosa. CONCLUSION: Early-onset rectal cancer is rarely associated with common hereditary syndromes. The tumour microenvironment is characterized by a high frequency of mutations impairing the local immune surveillance mechanisms and low expression of immune editing-related genes. A constitutively low number of CD4 T cells associated with a high number of T regulators indicates an imbalance in the immune surveillance mechanisms.

Predictors of urinary tract infection after lower gastrointestinal surgery.

BACKGROUND: Urinary tract infections (UTIs) cause postoperative morbidity in patients undergoing lower gastrointestinal (GI) surgery that can prolong postoperative hospital stays. In patients with a fever of unknown origin (FUO), clinicians ignore what to do while waiting for the results of the urine culture test. This study aimed to develop a nomogram predicting UTI in the case of postoperative FUO. METHODS: This observational, retrospective study included all consecutive patients from 1 November 2020 to 1 November 2021 undergoing lower-GI surgery at the Chirurgia Generale 3, University Hospital of Padua, Italy. A nomogram was created and externally validated in 90 consecutive patients undergoing urine culture tests for FUO at the Chirurgia Oncologica Unit, Veneto Institute of Oncology. RESULTS: In the development cohort, 109 (N = 109) patients performed a urine culture test for FUO, and 39 were diagnosed with UTI. In a multivariate analysis of patients who underwent urine culture tests for FUO, UTI was associated with female sex, older age, and duration of catheterization at the date of the urine culture test. We developed a nomogram to predict UTI in surgical patients with a C-index of 0.76. In the validation cohort, 90 consecutive patients, who had lower-GI surgery, underwent a urine culture test for FUO and were tested with this nomogram. In the validation cohort, the C-index of the nomogram for predicting a positive urine culture test was 0.71. CONCLUSIONS AND RELEVANCE: UTIs are a common problem in patients undergoing lower-GI surgery. A nomogram including the major risk factors may help to reduce the inappropriate use of antibiotics during the period awaiting the result of the urine culture test.

Leaving behind a diseased small bowel during surgery for Crohn's disease: Long-term outcomes.

PURPOSES: Stricture is a common complication of Crohn's disease (CD) and may be treated with bowel-sparing procedures. Our study analyzed what happens in terms of intestinal and systemic inflammation when the diseased bowel is left behind following surgery. METHODS: In this retrospective study, we enrolled 42 consecutive patients who underwent strictureplasty (alone or with resection) for stricturing CD. Control patients who underwent complete diseased bowel resection were identified and propensity score-matched for the sex, age, and history of abdominal surgery. Biohumoral values were collected at follow-up examinations at 1, 6, and 12 months after surgery. Magnetic resonance imaging (MRI) was performed before and after strictureplasty in 19 patients. RESULTS: In the strictureplasty group, fecal calprotectin levels were decreased at 12 months (p = 0.03), whereas in the resectiongroup, they were decreased at 6 months (p = 0.02). On MRI, the ADC [apparent diffusion coefficient] (p < 0.001), wall thickness (p = 0.046) and Magnetic Resonance Index of Activity (MaRIA) (p < 0.001) and Clermont (p < 0.001) scores were improved after strictureplasty. Surgical recurrence was more frequent in the strictureplasty group than in the resection group (p = 0.003). CONCLUSIONS: Our retrospective study showed that even if the diseased bowel was left behind after surgery, the intestinal inflammatory activity still decreased. However, the permanence of the diseased bowel still increased the risk of reoperation, probably because of the fibrotic nature of the stenosis and the multifocality of CD.

Crohn's Disease-Related Stoma Complications and Their Impact on Postsurgical Course.

INTRODUCTION: Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract. The diversion through a colostomy or an ileostomy is sometimes required for disease control. In these patients, common stoma-related complications sum up with CD-related complications and often require revisional surgery. METHODS: The aim of the study was to assess stoma morbidity after surgery for CD and to identify the burden of CD-related or CD-associated complications. Thus, details of past medical history, surgery, and follow-up of 54 consecutive patients operated on for CD with any sort of stoma were retrieved from the stoma therapist prospectively maintained database. RESULTS: In our series, 23 patients had a colostomy, and 31 patients had an ileostomy. Complications occurred after stoma creation in 38 patients (70%) at a median of 1.3 months (interquartile range 0.6-7.2). CD-related complications arose in 8 patients (including pyoderma gangrenosum in 3 patients, peristomal fistulae in 2, granulomas in 2, and peristomal abscess in 1). Patients with CD-related complications tended to have a shorter disease duration (p = 0.07) and higher occurrence of CD-related complications was associated with end-stoma (p = 0.006). In this cohort, 11 cases had to be surgically treated for peristomal fistulae or abscess, parastomal hernia, prolapse, pyoderma gangrenosum, and recurrent CD. DISCUSSION/CONCLUSIONS: In patients with CD, stoma creation is burdened by a high rate of postoperative complication and a relevant rate is specifically related to CD. Often these patients are required to be reoperated on to redo the stoma. Moreover, end-stoma configuration and aggressive CD phenotype are associated to a higher rate of complications.

Can Vascular Endothelial Growth Factors and CD34 Expression Implement NICE (Narrow-Band Imaging International Colorectal Endoscopic) Classification in Colorectal Polypoid Lesion Diagnosis?

BACKGROUND: Vascular endothelial growth factor (VEGF) is a subfamily of growth factors involved in angiogenesis; CD34+ cells are normally found in endothelial progenitor cells and endothelial cells of blood vessels. Colonic adenomatous polyps may not always be completely removable endoscopically, and a preoperative diagnosis might still be necessary. The aim of the study was to evaluate whether VEGF-A, VEGF-C and CD34 mRNA expression along colorectal carcinogenesis steps can implement NICE (Narrow-Band Imaging International Colorectal Endoscopic) classification in the diagnosis of malignancy in colorectal polypoid lesions. METHODS: Seventy-one subjects with colonic adenoma or cancer who underwent screening narrow-band imaging (NBI) colonoscopy were prospectively enrolled in the MICCE1 project (Treviso center). Polyps were classified according to the NICE classification. Real-time RT-PCR for VEGF-A, VEGF-C and CD34 mRNA expression was performed. Nonparametric statistics, receiver-operating characteristic curve analysis and logistic multiple regression analysis were used. RESULTS: VEGF-A and CD34 mRNA expression was significantly higher in sessile adenomas than in polypoid ones (p < 0.001 and p = 0.01, respectively). VEGF-A, VEGF-C and CD34 mRNA expression was significantly higher in adenocarcinoma than in adenoma (p = 0.01, p = 0.01 and p = 0.01, respectively). The accuracy of VEGF-A, VEGF-C and CD34 mRNA expression for prediction of malignancy was 0.79 (95% CI 0.65-0.90), 0.81 (95% CI 0.66-0.91) and 0.80 (95% CI 0.65-0.90), respectively, while the accuracy of the NICE classification was 0.85 (95% CI 0.72-0.94). The determination coefficient R2, which indicates the amount of the variability explained by a regression model, for NICE classification alone was 0.24 (p < 0.001). A regression model that included NICE classification and VEGF-C mRNA expression showed an R2 = 0.39 as well as a model including NICE classification and CD34 mRNA levels. CONCLUSIONS: This study demonstrated that VEGF-C and CD34 mRNA levels might be useful to stratify colorectal polyps in different risk of progression classes by implementing the accuracy of the NICE classification. Studies on in vivo detection of these markers are warranted.

CD80 down-regulation is associated to aberrant DNA methylation in non-inflammatory colon carcinogenesis.

BACKGROUND: The lack of positive costimulatory molecules represents one of the mechanisms by which tumor cells evade immune surveillance. Promoter hypermethylation plays a major role in cancer development through transcriptional silencing of critical genes. The aim of this study was to examine the expression of the costimulatory molecule CD80 in relationship with genomic methylation in non-inflammatory colon carcinogenesis. METHODS: Colonic mucosal samples were collected from healthy subjects (n = 30) and from dysplastic adenoma (n = 14), and colon adenocarcinoma (n = 10). DNA methyltransferases-1, -3a, -3b and CD80 mRNA expression were quantified by real time qRT-PCR. The methylation status of CDH13, APC, MLH1, MGMT1 and RUNX3 gene promoters was assessed by methylation-specific PCR. CD80 expression was assessed in HT29, HCT-15 and LoVo cell lines after treatment with the DNA-methyltransferase inhibitor 5-Aza-2'-deoxycytidine. RESULTS: CD80 mRNA levels were significantly lower in the non-inflammatory dysplastic colonic mucosa of patients with one or more methylated genes and inversely correlated with patients' methylation scores (τ = -0.41, p = 0.05 and τ = -0.37, p = 0.05, respectively). Treatment with 5-Aza-2'-deoxycytidine significantly increased CD80 expression both in terms of the level of CD80 mRNA (p = 0.007) and of CD80+ cells (p = 0.003). CONCLUSIONS: These results indicate that the failure of immune surveillance mechanisms in non-inflammatory colon carcinogenesis may be linked to genomic methylation directly or indirectly affecting CD80 expression.

TAK1 is a key modulator of the profibrogenic phenotype of human ileal myofibroblasts in Crohn's disease.

Transforming growth factor (TGF)-ß-activated kinase 1 (TAK1) signaling can mediate inflammatory responses as well as tissue remodeling. Intestinal mucosal myofibroblast (IMF) activation drives gut fibrosis in Crohn's disease (CD); however, the molecular pathways involved are largely unknown. Thus we investigated the yet-unknown expression and function of TAK1 in human CD-associated fibrosis. Ileal surgical specimens, ileal biopsies, and IMF isolated from controls and CD patients were analyzed for TAK1 and its active phosphorylated form (pTAK1) by Western blotting, immunohistochemistry, and real-time quantitative PCR. TAK1 pharmacological inhibition and silencing were used to assess its role in collagen and inflammatory cytokine synthesis in IMF. TAK1 and pTAK1 levels increased in ileum specimens from CD patients compared with controls and correlated to tissue fibrosis. Similarly, TAK1 mRNA in ileal biopsies of CD patients correlated with fibrogenic marker expression but not inflammatory cytokines. CD-derived IMF showed higher TAK1 and pTAK1 expression associated with increased collagen1(α)1 mRNA levels compared with control IMF. TGF-ß1 promoted pTAK1 nuclear translocation and collagen synthesis. TAK1 inhibition or silencing significantly reduced TGF-ß1-stimulated collagen production and normalized the profibrogenic phenotype of CD-derived IMF. Taken together, these data suggest that TAK1 activation and nuclear translocation induce and maintain a fibrogenic phenotype in the IMF. Thus the TAK1 signaling pathway may represent a suitable target to design new, antifibrotic therapies.

Intestinal Surgery for Crohn's Disease: Role of Preoperative Therapy in Postoperative Outcome.

PURPOSES: Patients affected by Crohn's disease (CD) require lifelong medical therapy, but they can also often require abdominal surgery. The effect of CD therapy on postoperative course is still unclear. The aim of this study was to evaluate the effect of preoperative medical therapy on the outcome of intestinal surgery in these patients. METHODS: Data from a consecutive series of 167 patients with CD operated on at the University of Padova Hospital from 2000 to 2013 were retrieved. Data of preoperative therapy during the 6 months before surgery were available for 146 patients who were enrolled in this retrospective study. Clinical data and surgical details were retrieved and postoperative complications and reoperation were considered outcome measures. Univariate and multivariate analysis were performed. RESULTS: No significant difference was observed between patients without data about their preoperative therapy and those with them. Eight patients underwent reoperation in the first 30 postoperative days: two of them for anastomotic leak, three for bleeding, one for obstruction and two for abdominal wound dehiscence. At multivariate analysis, preoperative adalimumab and budesonide resulted to be an independent predictor of reoperation (OR = 7.67 (95% CI = 1.49-39.20), p = 0.01 and OR = 6.7749 (95% CI = 0.98-46.48), p = 0.05, respectively). At multivariate analysis neither pharmacological nor clinical variables resulted to predict anastomotic leak. CONCLUSIONS: In our series, adalimumab seemed to be associated to early reoperation after intestinal surgery. This may be due to a worst disease severity in patients who needed surgery in spite of biological therapy. Preoperative tapering of budesonide dose seems a safe option before elective abdominal surgery for CD.

Short-Chain Fatty Acids and Human Health: From Metabolic Pathways to Current Therapeutic Implications.

The gastrointestinal tract is home to trillions of diverse microorganisms collectively known as the gut microbiota, which play a pivotal role in breaking down undigested foods, such as dietary fibers. Through the fermentation of these food components, short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are produced, offering numerous health benefits to the host. The production and absorption of these SCFAs occur through various mechanisms within the human intestine, contingent upon the types of dietary fibers reaching the gut and the specific microorganisms engaged in fermentation. Medical literature extensively documents the supplementation of SCFAs, particularly butyrate, in the treatment of gastrointestinal, metabolic, cardiovascular, and gut-brain-related disorders. This review seeks to provide an overview of the dynamics involved in the production and absorption of acetate, propionate, and butyrate within the human gut. Additionally, it will focus on the pivotal roles these SCFAs play in promoting gastrointestinal and metabolic health, as well as their current therapeutic implications.

Refractory Crohn's Disease: Perspectives, Unmet Needs and Innovations.

Crohn's disease (CD) is a complex, chronic inflammatory bowel disease characterized by unpredictable flare-ups and periods of remission. Despite advances in treatment, CD remains a significant health burden, leading to substantial direct healthcare costs and out-of-pocket expenses for patients, especially in the first-year post-diagnosis. The impact of CD on patients' quality of life is profound, with significant reductions in physical, emotional, and social well-being. Despite advancements in therapeutic options, including biologics, immunomodulators, and small molecules, many patients struggle to achieve or maintain remission, leading to a considerable therapeutic ceiling. This has led to an increased focus on novel and emerging treatments. This context underscores the importance of exploring advanced and innovative treatment options for managing refractory CD. By examining the latest approaches, including immunomodulators, combination therapies, stem cell therapies, and emerging treatments like fecal microbiota transplantation and dietary interventions, there is an opportunity to gain a comprehensive understanding of how best to address and manage refractory cases of CD.

Colorectal cancer and inflammatory bowel diseases share common salivary proteomic pathways.

Inflammatory bowels diseases (IBD) are high risk conditions for colorectal cancer (CRC). The discovery of IBD and CRC noninvasive protein/peptide biomarkers using saliva and feces was the aim of this study involving 20 controls, 25 IBD (12 Crohn's Disease-CD), 37 CRC. By untargeted proteomic (LTQ-Orbitrap/MS), a total of 152 proteins were identified in saliva. Absent in controls, 73 proteins were present in both IBD and CRC, being mainly related to cell-adhesion, cadherin-binding and enzyme activity regulation (g-Profiler). Among the remaining 79 proteins, 14 were highly expressed in CD and 11 in CRC. These proteins clustered in DNA replication/expression and innate/adaptive immunity. In stool, endogenous peptides from 30 different proteins were identified, two being salivary and CD-associated: Basic Proline-rich Protein 1 (PRBs) and Acidic Proline-rich Phosphoprotein. Biological effects of the PRBs-related peptides GQ-15 and GG-17 found in CD stool were evaluated using CRC cell lines. These peptides induced cell proliferation and activated Erk1/2, Akt and p38 pathways. In conclusion, the salivary proteome unveiled DNA stability and immunity clusters shared between IBD and CRC. Salivary PRB-derived peptides, enriched in CD stool, stimulate CRC cell proliferation and the pro-oncogenic RAS/RAF/MEK/ERK and PI3K/AKT/mTOR pathways suggesting a potential involvement of PRBs in IBD and cancer pathogenesis.

Association between Ustekinumab Trough Levels, Serum IL-22, and Oncostatin M Levels and Clinical and Biochemical Outcomes in Patients with Crohn's Disease.

Background: Ustekinumab (UST) has demonstrated effectiveness in treating patients with Crohn's disease. Monitoring treatment response can improve disease management and reduce healthcare costs. We investigated whether UST trough levels (TLs), serum IL22, and Oncostatin M (OSM) levels could be early indicators of non-response by analysing their correlation with clinical and biochemical outcomes in CD. Methods: Patients with CD initiating UST treatment from October 2018 to September 2020 were enrolled at six Italian centres for inflammatory bowel disease (IBD). Clinical and biochemical data were collected at four time points: baseline, second subcutaneous (SC) dose, fourth SC dose, and 52 weeks. TLs were measured during maintenance, at the second SC dose, and at the fourth SC dose. IL-22 and OSM serum levels were assessed at baseline and the second SC dose. We analysed whether TLs, IL22 levels, and OSM serum levels were associated with clinical response, clinical remission, biochemical remission, and endoscopic remission using the appropriate statistical tests. Results: Out of eighty-four initially enrolled patients, five were lost to follow-up, and eleven discontinued the drug before 52 weeks. At the 52-week time point, 47% achieved biochemical remission based on faecal calprotectin levels, and 61.8% achieved clinical remission. TLs at the second SC dose significantly correlated with biochemical remission at the same time point (p = 0.011). However, TLs did not correlate with clinical remission. Baseline OSM levels did not correlate with biochemical or clinical remission or response. IL22 levels notably decreased during UST therapy (p = 0.000), but its values did not correlate with biochemical or clinical remission. Conclusions: UST is an effective therapy for patients with CD. TLs measured at the second SC dose significantly correlated with biochemical remission, emphasising their potential role in treatment monitoring. Levels of OSM and IL-22, despite a significant decrease in the latter during therapy, did not exhibit correlations with clinical or biochemical outcomes in our study. Further studies are needed to confirm these findings.

Oral administration of Lactobacillus casei DG® after ileostomy closure in restorative proctocolectomy: a randomized placebo-controlled trial (microbiota and immune microenvironment in pouchitis -MEP1).

Pouchitis is an idiopathic inflammatory disease that may occur in ileal pouches, and it can lead to ileal pouch failure. This was a single-center, randomized, double-blinded, placebo-controlled trial that assessed the effect of Lactobacillus casei (L. casei) DG®, a probiotic strain, on the ileal pouch mucosa to determine the crosstalk between microbiota and mucosal immune system. Fifty-two patients undergoing restorative proctocolectomy were recruited and randomly assigned to receive a daily oral supplementation of L. casei DG® (n = 26) or placebo (n = 26) for 8 weeks from the ileostomy closure (T0) to a pouch endoscopy after 8 weeks (T1) and 1 year (T2). Ileal pouch mucosa samples were collected at T0, T1, and T2. At T1, the L. casei DG®-supplemented group showed a significant reduction of inflammatory cytokines levels compared to T0 baseline levels in the pouch mucosa, whereas in the placebo group cytokines levels resulted stable. In conclusion, probiotic manipulation of mucosal microbiota by L. casei DG®-supplementation after stoma closure in patients who underwent restorative proctocolectomy has a beneficial impact on the ileal pouch microenvironment. Registration number: NCT03136419 (http://www.clinicaltrials.gov).

Extraintestinal Cancers in Inflammatory Bowel Disease: A Literature Review.

BACKGROUND: Inflammatory bowel disease (IBD) is a group of chronic multifactorial inflammatory disorders including two major entities: Crohn's disease (CD) and ulcerative colitis (UC). Preliminary evidence suggests that patients with IBD may be at increased risk of developing intestinal and extraintestinal cancers (EICs). Actually, little is known about the association between IBD and EICs, and there is ever-growing concern regarding the safety of immunomodulators and biological therapy, which may represent a risk factor for carcinogenesis. AIMS: The aim of this review is to summarize the evidence regarding the association between IBD and EICs, the safety of immunomodulators and biological therapy and the management of immunomodulators and biologic agents in IBD patients with prior or current EICs. RESULTS: IBD patients have a higher risk of developing different forms of extraintestinal solid organ tumors and hematological malignancies. Immunomodulators and biological therapy may increase the risk of developing some types of EICs and may be consciously used in patients with IBD and current or prior history of malignancy. CONCLUSIONS: Decisions regarding the use of immunomodulators or biological therapies should be made on an individual basis, considering a multidisciplinary approach involving oncologists.

IMMUNOREACT 5: female patients with rectal cancer have better immune editing mechanisms than male patients - a cohort study.

BACKGROUND: Studies evaluating sex differences in colorectal cancer (CRC) tumor microenvironment are limited, and no previous study has focused on rectal cancer patients' constitutive immune surveillance mechanisms. The authors aimed to assess gender-related differences in the immune microenvironment of rectal cancer patients. METHODS: A systematic review and meta-analysis were conducted up to 31 May 2021, including studies focusing on gender-related differences in the CRC tumor microenvironment. Data on the mutational profile of rectal cancer were extracted from the Cancer Genome Atlas (TCGA). A subanalysis of the two IMMUNOREACT trials (NCT04915326 and NCT04917263) was performed, aiming to detect gender-related differences in the immune microenvironment of the healthy mucosa in patients with early (IMMUNOREACT 1 cohort) and locally advanced rectal cancer following neoadjuvant therapy (IMMUNOREACT 2 cohort). In the retrospective IMMUNOREACT 1 cohort (therapy naive), the authors enrolled 442 patients (177 female and 265 male), while in the retrospective IMMUNOREACT 2 cohort (patients who had neoadjuvant therapy), we enrolled 264 patients (80 female and 184 male). In the prospective IMMUNOREACT 1 cohort (therapy naive), the authors enrolled 72 patients (26 female and 46 male), while in the prospective IMMUNOREACT 2 cohort (patients who had neoadjuvant therapy), the authors enrolled 105 patients (42 female and 63 male). RESULTS: Seven studies reported PD-L1 expression in the CRC microenvironment, but no significant difference could be identified between the sexes. In the TGCA series, mutations of SYNE1 and RYR2 were significantly more frequent in male patients with rectal cancer. In the IMMUNOREACT 1 cohort, male patients had a higher expression of epithelial cells expressing HLA class I, while female patients had a higher number of activated CD4+Th1 cells. Female patients in the IMMUNOREACT 2 cohort showed a higher infiltration of epithelial cells expressing CD86 and activated cytotoxic T cells (P=0.01). CONCLUSIONS: Male patients have more frequent oncogene mutations associated with a lower expression of T-cell activation genes. In the healthy mucosa of female patients, more Th1 cells and cytotoxic T cells suggest a potentially better immune response to the tumor. Sex should be considered when defining the treatment strategy for rectal cancer patients or designing prognostic scores.

Validation of the Padova Prognostic Score for Colitis in Predicting Long-Term Outcome After Restorative Proctocolectomy.

Background: In 10%-20% of cases it is impossible to make a differential diagnosis between ulcerative colitis and Crohn's colitis. A 50% failure rate of J pouch ilea-anal anastomosis is observed in Crohn's colitis. In 2009, we created the Padua Prognostic Score for Colitis (PPSC) to predict the long-term clinical and functional outcome and quality of life of patients undergoing restorative proctocolectomy with J pouch. The aim of the present study is to establish and validate the accuracy of a prognostic score for chronic inflammatory bowel diseases (IBD). Patient population and methods: The PPSC was created in 2009 by integrating clinical and histological information of patients undergoing RPC. It included preoperative perianal abscess or fistula, rectal sparing, terminal ileum involvement, skip lesions and histological diagnosis of indeterminate colitis or Crohn's colitis on the operative specimen. The validity of this score was tested in predicting postoperative abscess or fistula, anal canal disease, pouchitis, pouch failure and new diagnosis of Crohn's disease. Correlation analysis, ROC curve analysis and survival analysis were used to validate the PPSC in a different cohort from the previous one. Results: We retrospectively enrolled in this study 138 consecutive patients undergoing CPR for ulcerative colitis (n = 127) or indeterminate colitis (n = 11) in our institution since 2005 to 2020. In this period, we observed 11 patients with postoperative abscess or fistula, 3 with anal canal disease, 40 with pouchitis, 6 with pouch failure and 6 with new diagnosis of Crohn's disease. In the new validation cohort, the PPSC confirmed to have a good accuracy in predicting the onset of postoperative CD (AUC = 74.5%, p = 0.018). Kaplan Meier curves demonstrate how a PPSC over 1 can reliably predicts the long-term onset of, pouchitis (p = 0.002) and anal abscess or fistulae (p = 0.04). Conclusions: In this validation study we confirmed the accuracy of the PPSC in predicting postoperative fistulas or abscesses and pouchitis. Therefore, we believe that in clinical practice patients with a PPSC score greater than 1 should be warned of this risk of possible Crohn's disease diagnosis and pouch failure.