The risk of colorectal cancer in patients with ulcerative colitis

The metabolomics analysis of cecal contents elucidates significant metabolites involved in the therapeutic effects of total flavonoids derived from Sonchus arvensis L. in male C57BL/6 mice with ulcerative colitis

Ulcerative colitis (UC), an inflammatory disease affecting the colon and rectal mucosa, is characterized by chronic and heterogeneous behavior of unknown origin. The primary cause of UC is chronic inflammation, which is closely linked to the development of colorectal cancer. Sonchus arvensis L. (SAL), a plant consumed worldwide for its nutritional and medicinal properties, holds significance in this context. In this study, we employed the total flavone in SAL as a treatment for male C57BL/6 mice with UC. The cecal contents metabolic profile of C57BL/6 mice in different groups, including UC (group ML; n = 5), UC treated with aspirin (group AN; n = 5), UC treated with the total flavone in SAL (group FE; n = 5), and healthy male C57BL/6 mice (group CL; n = 5), was examined using UHPLC-Triple-TOF-MS. Through the identification of variations in key metabolites associated with UC and the exploration of their underlying biological mechanisms, our understanding of the pathological processes underlying this condition has been enhanced. This study identified a total of seventy-three metabolites that have a significant impact on UC. Notably, the composition of total flavone in SAL, a medication used for UC treatment, differs from that of aspirin due to the presence of four distinct metabolites (13,14-Dihydro-15-keto-PGE2, Prostaglandin I2 (PGI2), (20R,22R)-20,22-dihydroxycholesterol, and PS (18:1(9Z)/0:0)). These metabolites possess unique characteristics that set them apart. Moreover, the study identified a total of eleven pathways that were significantly enriched in mice with UC, including Aminoacyl-tRNA biosynthesis, Valine, leucine and isoleucine biosynthesis, Linoleic acid metabolism, PPAR signaling pathway, mTOR signaling pathway, Valine, leucine and isoleucine degradation, Lysine degradation, VEGF signaling pathway, Melanogenesis, Endocrine and other factor-regulated calcium reabsorption, and Cocaine addiction. These findings contribute to a better understanding of the metabolic variations in UC following total flavonoids of SAL therapy and provide valuable insights for the treatment of UC.Keywords: Ulcerative colitis; Total flavonoids of Sonchus arvensis L.; Key metabolites; Metabonomics; Cecal contents of male C57BL/6 mice.

The Cross-talk Between Intestinal Microbiota and MDSCs Fuels Colitis-associated Cancer Development

Intestinal chronic inflammation is associated with microbial dysbiosis and accumulation of various immune cells including myeloid-derived suppressor cells (MDSC), which profoundly impact the immune microenvironment, perturb homeostasis and increase the risk to develop colitis-associated colorectal cancer (CAC). However, the specific MDSCs-dysbiotic microbiota interactions and their collective impact on CAC development remain poorly understood. In this study, using a murine model of CAC, we demonstrate that CAC-bearing mice exhibit significantly elevated levels of highly immunosuppressive MDSCs, accompanied by microbiota alterations. Both MDSCs and bacteria that infiltrate the colon tissue and developing tumors can be found in close proximity, suggesting intricate MDSC-microbiota cross-talk within the tumor microenvironment. To investigate this phenomenon, we employed antibiotic treatment to disrupt MDSC-microbiota interactions. This intervention yielded a remarkable reduction in intestinal inflammation, decreased MDSC levels, and alleviated immunosuppression, all of which were associated with a significant reduction in tumor burden. Furthermore, we underscore the causative role of dysbiotic microbiota in the predisposition toward tumor development, highlighting their potential as biomarkers for predicting tumor load. We shed light on the intimate MDSCs-microbiota cross-talk, revealing how bacteria enhance MDSC suppressive features and activities, inhibit their differentiation into mature beneficial myeloid cells, and redirect some toward M2 macrophage phenotype. Collectively, this study uncovers the role of MDSC-bacteria cross-talk in impairing immune responses and promoting tumor growth, providing new insights into potential therapeutic strategies for CAC.

SIGNIFICANCE

MDSCs-dysbiotic bacteria interactions in the intestine play a crucial role in intensifying immunosuppression within the CAC microenvironment, ultimately facilitating tumor growth, highlighting potential therapeutic targets for improving the treatment outcomes of CAC.

Promoter methylation levels of microRNA-124 in non-neoplastic rectal mucosa as a potential biomarker for ulcerative colitis-associated colorectal cancer in pediatric-onset patients

PURPOSE

To determine the methylation level of the miR-124 promoter in non-neoplastic rectal mucosa of patients with pediatric-onset ulcerative colitis (UC) to predict UC-associated colorectal cancer (UC-CRC).

METHODS

Between 2005 and 2017, non-neoplastic rectal tissue specimens were collected from 86 patients with UC, including 13 patients with UC-CRC; cancer tissues were obtained from the latter group. The methylation status of the miR-124 promoter was quantified using bisulfite pyrosequencing and compared between pediatric- and adult-onset UC patients.

RESULTS

Patients with pediatric-onset UC experienced a significantly shorter disease duration than those with adult-onset UC. The levels of miR-124 promoter methylation in non-neoplastic rectal mucosa were positively correlated with the age at the diagnosis and duration of UC. The rate of increase in miR-124 methylation was accelerated in patients with pediatric-onset UC compared to those with adult-onset UC. Furthermore, the miR-124 methylation levels in non-neoplastic rectal mucosa were significantly higher in patients with UC-CRC than in those with UC alone (P = 0.02). A receiver operating characteristic analysis revealed that miR-124 methylation in non-neoplastic tissue discriminated between patients with pediatric-onset UC with or without CRC.

CONCLUSION

miR-124 methylation in non-neoplastic rectal mucosa may be a useful biomarker for identifying patients with pediatric-onset UC who face the highest risk of developing UC-CRC.

Identifying the real-world challenges of dysplasia surveillance in inflammatory bowel disease: a retrospective cohort study in a tertiary health network

BACKGROUND

Dysplasia surveillance in inflammatory bowel disease (IBD) is often suboptimal and deviates from guidelines.

AIMS

To assess dysplasia surveillance behaviours and adherence to guidelines amongst a large tertiary teaching health network with a specialised IBD unit to identify areas where dysplasia surveillance could be improved.

METHODS

A retrospective audit of IBD surveillance colonoscopy practice over an 18-month period was performed using the Provation Endoscopy Database and the hospital's primary sclerosing cholangitis database.

RESULTS

The audit identified 115 dysplasia surveillance colonoscopies. A total of 37% of index dysplasia colonoscopies were outside recommended guidelines. A total of 10% had inadequate bowel preparation and only 40% had excellent bowel preparation. A total of 28% of patients underwent dye-based chromoendoscopy and 69% underwent high-definition white-light endoscopy. Dye chromoendoscopy was more likely to be used by IBD specialists than interventional endoscopists (P = 0.008) and other endoscopists (P = 0.004). Only IBD specialists and interventional endoscopists used dye chromoendoscopy. Dysplasia or colorectal cancer was detected in 3.4% of the colonoscopies. Overall, the several dysplasia examinations were lower than expected.

CONCLUSIONS

Dysplasia surveillance in the IBD population remains an area of improvement given the current national guidelines. IBD specialists are more likely to perform dye chromoendoscopy than other endoscopists/gastroenterologists. Dysplasia rates in this real-world contemporary setting are less than expected in historical studies and may represent improvements in IBD management principles and medications.

[Conventional and non-conventional dysplasia in patients with inflammatory bowel disease]

Compared to the general population, patients with inflammatory bowel disease (IBD), both ulcerative colitis (UC) or Crohn's disease (CD), are at increased risk of developing some cancers, particularly colorectal cancers (CRC). CRCs, the vast majority of which are adenocarcinomas, develop from a precancerous lesion called dysplasia (or intraepithelial neoplasia) via an inflammation-dysplasia-adenocarcinoma sequence. The advancements of new endoscopic techniques, including visualisation and resection techniques, has led to a reclassification of dysplasia lesions into visible and invisible lesions and their therapeutic management, with a more conservative approach to the colorectal setting. In addition, besides conventional dysplasia, of intestinal phenotype, classically described in IBD, non-conventional dysplasias (as opposed to conventional dysplasia of intestinal phenotype) are now described, including at least seven subtypes. Recognition of these unconventional subtypes, which are still poorly known from pathologists, is becoming crucial, as some of these subtypes appear to be at high risk of developing advanced neoplasia (i.e. high-grade dysplasia or CRC). This review briefly describes the macroscopic features of dysplastic lesions in IBD, as well as their therapeutic management, followed by the clinicopathological features of these dysplastic lesions, with particular emphasis on the new subtypes of unconventional dysplasia, both from a morphological and molecular point of view.

Deficiency of the Two-Pore Potassium Channel KCNK9 Impairs Intestinal Epithelial Cell Survival and Aggravates Dextran Sodium Sulfate-Induced Colitis

BACKGROUND & AIMS

The 2-pore potassium channel subfamily K member 9 (KCNK9) regulates intracellular calcium concentration and thus modulates cell survival and inflammatory signaling pathways. It also was recognized as a risk allele for inflammatory bowel disease. However, it remains unclear whether KCNK9 modulates inflammatory bowel disease via its impact on immune cell function or whether its influence on calcium homeostasis also is relevant in intestinal epithelial cells.

METHODS

Kcnk9^-/- mice were challenged with 3% dextran sulfate sodium (DSS) to induce experimental acute colitis. Primary cultures of intestinal epithelial cells were generated, and expression of potassium channels as well as cytosolic calcium levels and susceptibility to apoptosis were evaluated. Furthermore, we evaluated whether KCNK9 deficiency was compensated by the closely related 2-pore potassium channel KCNK3 in vivo or in vitro.

RESULTS

Compared with controls, KCNK9 deficiency or its pharmacologic blockade were associated with aggravated DSS-induced colitis compared with wild-type animals. In the absence of KCNK9, intestinal epithelial cells showed increased intracellular calcium levels and were more prone to mitochondrial damage and caspase-9-dependent apoptosis. We found that expression of KCNK3 was increased in Kcnk9^-/- mice but did not prevent apoptosis after DSS exposure. Conversely, increased levels of KCNK9 in Kcnk3^-/- mice were associated with an ameliorated course of DSS-induced colitis.

CONCLUSIONS

KCNK9 enhances mitochondrial stability, reduces apoptosis, und thus supports epithelial cell survival after DSS exposure in vivo and in vitro. Conversely, its increased expression in Kcnk3^-/- resulted in less mitochondrial damage and apoptosis and was associated with beneficial outcomes in DSS-induced colitis.

Oral Conventional Synthetic Disease-Modifying Antirheumatic Drugs with Antineoplastic Potential: a Review

There is an increasing trend of malignancy worldwide. Disease-modifying antirheumatic drugs (DMARDs) are the cornerstones for the treatment of immune-mediated inflammatory diseases (IMIDs), but risk of malignancy is a major concern for patients receiving DMARDs. In addition, many IMIDs already carry higher background risks of neoplasms. Recently, the black box warning of malignancies has been added for Janus kinase inhibitors. Also, the use of biologic DMARDs in patients with established malignancies is usually discouraged owing to exclusion of such patients in pivotal studies and, hence, lack of evidence. In contrast, some conventional synthetic DMARDs (csDMARDs) have been reported to show antineoplastic properties and can be beneficial for patients with cancer. Among the csDMARDs, chloroquine and hydroxychloroquine have been the most extensively studied, and methotrexate is an established chemotherapeutic agent. Even cyclosporine A, a well-known drug associated with cancer risk, can potentiate the effect of some chemotherapeutic agents. We review the possible mechanisms behind and clinical evidence of the antineoplastic activities of csDMARDs, including chloroquine and hydroxychloroquine, cyclosporine, leflunomide, mycophenolate mofetil, mycophenolic acid, methotrexate, sulfasalazine, and thiopurines. This knowledge may guide physicians in the choice of csDMARDs for patients with concurrent IMIDs and malignancies.

Colorectal Cancer in Inflammatory Bowel Disease: Mechanisms and Management

Patients with inflammatory bowel disease (IBD) are at increased risk of developing colorectal cancer (CRC), despite decreases in CRC incidence in recent years. Chronic inflammation is the driver of neoplastic progression, resulting in dysplastic precursor lesions that may arise in multiple areas of the colon through a process of field cancerization. Colitis-associated CRC shares many molecular similarities with sporadic CRC, and preclinical investigations have demonstrated a potential role for the microbiome in concert with the host immune system in the development of colitis-associated colorectal cancer (CAC). Some unique molecular differences occur in CAC, but their role in the pathogenesis and behavior of inflammation-associated cancers remains to be elucidated. Nonconventional types of dysplasia have been increasingly recognized, but their natural history is not well defined, and they have not been incorporated into surveillance algorithms. The concept of cumulative inflammatory burden highlights the importance of considering histologic inflammation over time as an important risk factor for CAC. Dysplasia is arguably the most important risk factor for developing CAC, and advances have been made in the endoscopic detection and removal of precancerous lesions, thereby deferring or avoiding surgical resection. Some of the agents used to treat IBD are chemopreventive. It is hoped that by gaining better control of the underlying inflammation with newer medications and better endoscopic detection and management, a more sophisticated appreciation of clinicopathologic risk factors, and growing awareness of the genetic, immunologic, and environmental causes of colitis- associated neoplasia, that colitis-associated colorectal neoplasia will become even more predictable and manageable in the coming years.

Suppression of Transmembrane Tumor Necrosis Factor Alpha Processing by a Specific Antibody Protects Against Colitis-Associated Cancer

Soluble tumor necrosis factor-α (sTNF-α) plays an important role in colitis-associated cancer (CAC); however, little is known about transmembrane TNF-α (tmTNF-α). Here, we observed an increase in sTNF-α mainly in colitis tissues from an azoxymethane/dextran sodium sulfate (DSS)-induced CAC mouse model whereas tmTNF-α levels were chiefly increased on epithelial cells at the tumor stage. The ratio of intracolonic tmTNF-α/sTNF-α was negatively correlated with the levels of pro-inflammatory mediators (IL-1β, IL-6, and NO) and M1 macrophages but positively correlated with the infiltration of myeloid-derived suppressor cells, regulatory T cells, and the level of the anti-inflammatory cytokine IL-10, suggesting an anti-inflammatory effect of tmTNF-α. This effect of tmTNF-α was confirmed again by the induction of resistance to LPS in colonic epithelial cell lines NCM460 and HCoEpiC through the addition of exogenous tmTNF-α or transfection of the tmTNF-α leading sequence that lacks the extracellular segment but retains the intracellular domain of tmTNF-α. A tmTNF-α antibody was used to block tmTNF-α shedding after the first or second round of inflammation induction by DSS drinking to shift the time window of tmTNF-α expression ahead to the inflammation stage. Antibody treatment significantly alleviated inflammation and suppressed subsequent adenoma formation, accompanied by increased apoptosis. An antitumor effect was also observed when the antibody was administered at the malignant phase of CAC. Our results reveal tmTNF-α as a novel molecular marker for malignant transformation in CAC and provide a new insight into blocking the pathological process by targeting tmTNF-α processing.

AI based colorectal disease detection using real-time screening colonoscopy

Colonoscopy is an effective tool for early screening of colorectal diseases. However, the application of colonoscopy in distinguishing different intestinal diseases still faces great challenges of efficiency and accuracy. Here we constructed and evaluated a deep convolution neural network (CNN) model based on 117 055 images from 16 004 individuals, which achieved a high accuracy of 0.933 in the validation dataset in identifying patients with polyp, colitis, colorectal cancer (CRC) from normal. The proposed approach was further validated on multi-center real-time colonoscopy videos and images, which achieved accurate diagnostic performance on detecting colorectal diseases with high accuracy and precision to generalize across external validation datasets. The diagnostic performance of the model was further compared to the skilled endoscopists and the novices. In addition, our model has potential in diagnosis of adenomatous polyp and hyperplastic polyp with an area under the receiver operating characteristic curve of 0.975. Our proposed CNN models have potential in assisting clinicians in making clinical decisions with efficiency during application.

Epithelial TLR4 Signaling Activates DUOX2 to Induce Microbiota-Driven Tumorigenesis

BACKGROUND & AIMS

Chronic colonic inflammation leads to dysplasia and cancer in patients with inflammatory bowel disease. We have described the critical role of innate immune signaling via Toll-like receptor 4 (TLR4) in the pathogenesis of dysplasia and cancer. In the current study, we interrogate the intersection of TLR4 signaling, epithelial redox activity, and the microbiota in colitis-associated neoplasia.

METHODS

Inflammatory bowel disease and colorectal cancer data sets were analyzed for expression of TLR4, dual oxidase 2 (DUOX2), and NADPH oxidase 1 (NOX1). Epithelial production of hydrogen peroxide (H₂O₂) was analyzed in murine colonic epithelial cells and colonoid cultures. Colorectal cancer models were carried out in villin-TLR4 mice, carrying a constitutively active form of TLR4, their littermates, and villin-TLR4 mice backcrossed to DUOXA-knockout mice. The role of the TLR4-shaped microbiota in tumor development was tested in wild-type germ-free mice.

RESULTS

Activation of epithelial TLR4 was associated with up-regulation of DUOX2 and NOX1 in inflammatory bowel disease and colorectal cancer. DUOX2 was exquisitely dependent on TLR4 signaling and mediated the production of epithelial H₂O₂. Epithelial H₂O₂ was significantly increased in villin-TLR4 mice; TLR4-dependent tumorigenesis required the presence of DUOX2 and a microbiota. Mucosa-associated microbiota transferred from villin-TLR4 mice to wild-type germ-free mice caused increased H₂O₂ production and tumorigenesis.

CONCLUSIONS

Increased TLR4 signaling in colitis drives expression of DUOX2 and epithelial production of H₂O₂. The local milieu imprints the mucosal microbiota and imbues it with pathogenic properties demonstrated by enhanced epithelial reactive oxygen species and increased development of colitis-associated tumors. The inter-relationship between epithelial reactive oxygen species and tumor-promoting microbiota requires a 2-pronged strategy to reduce the risk of dysplasia in colitis patients.

MicroRNA Biomarkers in IBD-Differential Diagnosis and Prediction of Colitis-Associated Cancer

Inflammatory bowel disease (IBD) includes Crohn's disease (CD) and ulcerative colitis (UC). These are chronic autoimmune diseases of unknown etiology affecting the gastrointestinal tract. The IBD population includes a heterogeneous group of patients with varying disease courses requiring personalized treatment protocols. The complexity of the disease often delays the diagnosis and the initiation of appropriate treatments. In a subset of patients, IBD leads to colitis-associated cancer (CAC). MicroRNAs are single-stranded regulatory noncoding RNAs of 18 to 22 nucleotides with putative roles in the pathogenesis of IBD and colorectal cancer. They have been explored as biomarkers and therapeutic targets. Both tissue-derived and circulating microRNAs have emerged as promising biomarkers in the differential diagnosis and in the prognosis of disease severity of IBD as well as predictive biomarkers in drug resistance. In addition, knowledge of the cellular localization of differentially expressed microRNAs is a prerequisite for deciphering the biological role of these important epigenetic regulators and the cellular localization may even contribute to an alternative repertoire of biomarkers. In this review, we discuss findings based on RT-qPCR, microarray profiling, next generation sequencing and in situ hybridization of microRNA biomarkers identified in the circulation and in tissue biopsies.

Tofacitinib Reprograms Human Monocytes of IBD Patients and Healthy Controls Toward a More Regulatory Phenotype

BACKGROUND

The inhibition of Janus kinases (JAKs) and subsequent signal transducers and activators of transcription (STATs) by tofacitinib represents a new therapeutic strategy in inflammatory bowel diseases (IBD) as clinical trials have led to approval of tofacitinib for ulcerative colitis (UC) and hint at a possible efficacy for Crohn`s disease (CD). However, the impact of tofacitinib on cellular response of monocytes, which are key players in inflammatory responses, has not been investigated so far. We aimed to analyze JAK/STAT-inhibition by tofacitinib in monocytes of IBD patients and healthy controls.

METHODS

Primary monocytes of IBD patients with active disease and healthy controls (n = 18) were analyzed for cytokine expression and phenotype after granulocyte macrophage colony-stimulating factor (GM-CSF)/interferon (IFN)γ-stimulation and tofacitinib pretreatment (1-1000 nM) and capacity to induce Foxp3+-regulatory T cells (Tregs) in cocultures. In total, 20 UC patients and 21 CD patients were included. Additionally, dose-dependent inhibition of JAK/STAT-phosphorylation was analyzed in controls.

RESULTS

Pro-inflammatory costimulation with GM-CSF/IFNγ resulted in significant tumor necrosis factor (TNFα) and interleukin (IL)-6 increase, whereas IL-10 expression decreased in monocytes. Tofacitinib modulated the responses of activated monocytes toward a regulatory phenotype through reduced TNFα and IL-6 secretion and enhanced Treg induction in cocultures. However, in monocytes from active IBD patients, higher tofacitinib dosages were needed for blockade of pro-inflammatory cytokines. Tofacitinib induced stronger regulatory phenotypes in monocytes of UC patients, including more effective inhibition of pro-inflammatory pathways and better restoration of anti-inflammatory mechanisms as compared with CD-derived monocytes.

CONCLUSION

Tofacitinib dose-dependently reprograms monocytes toward a more regulatory cell type. This beneficial effect possibly results from selective JAK/STAT-blockade by adequate tofacitinib dosage with inhibition of pro-inflammatory responses and permission of a balance-shift toward regulatory pathways.

Distinct Disease Phenotype of Ulcerative Colitis in Patients With Coincident Primary Sclerosing Cholangitis: Evidence From a Large Retrospective Study With Matched Cohorts

BACKGROUND

Primary sclerosing cholangitis is a classical extraintestinal manifestation in patients with ulcerative colitis. However, the impact of primary sclerosing cholangitis on the disease course is incompletely understood.

OBJECTIVE

This study aimed to assess the impact of primary sclerosing cholangitis on disease phenotype and its course in patients with ulcerative colitis.

DESIGN

This is a retrospective study with 3:1 matched cohorts.

SETTINGS

Tertiary care center's electronic database was used for data analysis from 2000 and 2018.

PATIENTS

Of 782 patients with ulcerative colitis, 77 patients who had coincident primary sclerosing cholangitis were included.

MAIN OUTCOME MEASURES

The primary outcomes evaluated were disease characteristics including colonic disease activity, temporal change of disease course, colorectal neoplasia, and colectomy rates.

RESULTS

Disease activity during acute flares, assessed by the complete Mayo score, was significantly lower in patients with primary sclerosing cholangitis (6.2 vs 7.3; p < 0.001). In addition, disease activity in patients with primary sclerosing cholangitis was decreased, especially within the first 10 years after disease onset, and biological therapy with anti-tumor necrosis factor and anti-integrin agents was commenced less frequently (22% vs 35%; p = 0.043) and later (10-year risk: 17.4% vs 27.8%; p = 0.034). Patients with primary sclerosing cholangitis were younger at colitis diagnosis (23.3 vs 29.3 years; p < 0.001) and had more extensive disease (75% vs 46%; p < 0.001). Colorectal cancer was more frequently detected in patients with coincident primary sclerosing cholangitis (6/77 vs 16/705; p = 0.016). Colectomy rates did not differ between both groups (14.3% vs 14.5%; p = 0.56). In contrast, patients with ulcerative colitis had to undergo surgery more frequently because of therapy-refractant inflammation, whereas surgery due to neoplasia development was increased in patients with coincident primary sclerosing cholangitis (p = 0.013).

LIMITATIONS

The study was limited by its retrospective design.

CONCLUSION

Patients who have ulcerative colitis with coincident primary sclerosing cholangitis develop a distinct disease course characterized by an earlier disease onset and lower disease activity, but more frequent extensive disease manifestation and higher risk for colorectal cancer. See Video Abstract at http://links.lww.com/DCR/B45. FENOTIPO DE ENFERMEDAD DISTINTIVO DE LA COLITIS ULCERATIVA EN PACIENTES CON COLANGITIS ESCLEROSANTE PRIMARIA CONCOMITANTE: EVIDENCIA DE UN ESTUDIO RETROSPECTIVO GRANDE CON COHORTES EMPAREJADAS: La colangitis esclerosante primaria es una manifestación extraintestinal clásica en pacientes con colitis ulcerativa. Sin embargo, el impacto de la colangitis esclerosante primaria en el curso de la enfermedad no es comprendido completamente.Evaluar el impacto de la colangitis esclerosante primaria en el fenotipo y curso de la enfermedad en pacientes con colitis ulcerativa.Este es un estudio retrospectivo con cohortes emparejadas 3:1.La base de datos electrónica de un centro de atención terciaria se utilizó para el análisis de datos de 2000 a 2018.782 pacientes con colitis ulcerativa, 77 padecían colangitis esclerosante primaria concomitante y fueron incluidos.Se evaluaron las características de la enfermedad, incluida la actividad de enfermedad colónica, el cambio temporal del curso de la enfermedad, la neoplasia colorrectal y las tasas de colectomía.La actividad de la enfermedad durante los brotes agudos, evaluada por la puntuación completa de Mayo, fue significativamente menor en pacientes con colangitis esclerosante primaria (6.2 vs 7.3; p < 0.001). Además, la actividad de la enfermedad en pacientes con colangitis esclerosante primaria se redujo especialmente en los primeros 10 años después del inicio de la enfermedad, y la terapia biológica con agentes anti-TNF y anti-integrina se inició con menos frecuencia (22% vs 35%; p = 0.043) y más tarde (riesgo a 10 años: 17.4% vs 27.8%; p = 0.034). Los pacientes con colangitis esclerosante primaria eran más jóvenes en el momento del diagnóstico de colitis (23.3 vs 29.3 años; p < 0.001) y tenían enfermedad más extensa (75% vs 46%; p < 0.001). El cáncer colorrectal se detectó con mayor frecuencia en pacientes con colangitis esclerosante primaria concomitante (6/77 vs 16/705; p = 0.016). Las tasas de colectomía no fueron diferentes entre ambos grupos (14.3% vs 14.5%; p = 0.56). En contraste, los pacientes con colitis ulcerativa tuvieron que someterse a cirugía con mayor frecuencia debido a inflamación refractaria a la terapia, mientras que el desarrollo de neoplasia se incrementó en pacientes con colangitis esclerosante primaria concomitante (p = 0.013).El estudio estuvo limitado por su diseño retrospectivo.Los pacientes con colitis ulcerativa con colangitis esclerosante primaria concomitante desarrollan un curso de enfermedad distintivo caracterizado por un inicio temprano de la enfermedad y una menor actividad de la enfermedad, pero con manifestación de enfermedad extensa más frecuente y un mayor riesgo de cáncer colorrectal. Vea el resumen en video en http://links.lww.com/DCR/B45.

Risk of Colorectal Cancer in Ulcerative Colitis Patients: A Systematic Review and Meta-Analysis

Background

Ulcerative colitis (UC) patients have an increased risk for the development of colorectal cancer (CRC). Our aim was to assess the risk of CRC in UC patients compared with disease extent, disease duration, and geographic variation.

Methods

In this systematic review and meta-analysis, we searched PubMed, scientific meetings, and the bibliographies of identified articles, with English language restrictions for studies published from 1988 to 2018, and assessed the risk of CRC in UC patients. Patients with Crohn's disease, family history of CRC, and colorectal adenomatous polyp (CAP) were excluded from this research. The study was registered with PROSPERO, number CRD42018102213.

Findings

We included 58 studies that included 267566 UC patients. Extensive UC and left-sided UC had a higher risk of CRC than proctitis UC. Geography also played a role in UC-associated CRC development. The time of malignant transformation in Asian UC patients started after 10-20 years of this disease duration. North American UC-associated CRC patients significantly increased in more than 30 years of this disease duration.

Conclusion

In a systematic review of the literature, we found that disease extent, disease duration, and geography were strong, independent risk factors in UC-associated CRC development.

A Multifunctional Nanotherapy for Targeted Treatment of Colon Cancer by Simultaneously Regulating Tumor Microenvironment

Colitis-associated colon cancer (CAC) is a widely recognized cancer, while treatment with the existing chemotherapeutic drugs affords limited clinical benefits. Herein we proposed a site-specific, combination nanotherapy strategy for targeted treatment of CAC by the oral route. Methods: A reactive oxygen species (ROS)-responsive and hydrogen peroxide-eliminating material OCD was synthesized, which was further produced into a functional nanoparticle (OCD NP). The antioxidative stress and anti-inflammatory effects of OCD NP were examined by in vitro and in vivo experiments. By packaging an anticancer drug camptothecin-11 (CPT-11) into OCD NP, a ROS-responsive nanotherapy CPT-11/OCD NP was obtained, and its antitumor activity was evaluated by both in vitro and in vivo studies. Preliminary safety studies were also performed for CPT-11/OCD NP in mice. Results: OCD NP significantly attenuated oxidative stress and inhibited inflammatory response in different cells and mice with induced colitis. CPT-11/OCD NP could selectively release drug molecules under intestinal pH conditions and at high levels of ROS. In C26 murine colon carcinoma cells, this nanotherapy showed significantly higher antitumor activity compared to free CPT-11 and a non-responsive CPT-11 nanotherapy. Correspondingly, oral delivery of CPT-11/OCD NP notably inhibited tumorigenesis and tumor growth in mice with induced CAC. By combination therapy with the nanovehicle OCD NP in the inflammatory phase, more desirable therapeutic effects were achieved. Furthermore, CPT-11/OCD NP displayed excellent safety profile for oral administration at a dose that is 87.3-fold higher than that employed in therapeutic studies. Conclusions: Anticancer nanotherapies derived from intrinsic anti-inflammatory nanocarriers are promising for targeted combination treatment of inflammation-associated tumors by simultaneously shaping pro-inflammatory microenvironment toward a relatively normal niche sensitive to chemotherapy.

Colorectal cancer prevention in patients with ulcerative colitis

Ulcerative colitis is characterized by chronic inflammation, which may lead to the accumulation of high levels of pro-inflammatory cytokines within the colonic mucosa, and thus to dysplastic lesions and cancer. Although the trend is decreasing, ulcerative colitis patients still have a 2.4 fold higher risk of colorectal cancer compared to the general population. The key task is to control colonic inflammation, and a rapid step-up approach while closely monitoring intestinal inflammation are recommented. Surveillance colonoscopy program demonstrated its efficacy for reducing the incidence of colorectal cancer in ulcerative colitis. The impact of medication on the reduction of colorectal cancer risk was hardly investigated and it remains unclear whether they have intrinsic anti-neoplastic properties or only downregulate inflammatory pathways. Several studies showed a decreased risk of colorectal cancer in ulcerative colitis patients treated with 5-aminosalicylic acid and chemoprevention with mesalamine compounds is currently recommended. The current level of evidence is too low for thiopurines and anti-TNFα agents. Large, prospective cohort studies are ongoing and are likely to bring new findings about the impact of drugs on colorectal cancer risk in the current era of biologics.

Reduced Risk of Inflammatory Bowel Disease-associated Colorectal Neoplasia with Use of Thiopurines: a Systematic Review and Meta-analysis

BACKGROUND AND AIMS

The association between thiopurines and colorectal neoplasia risk remains controversial in inflammatory bowel disease [IBD] patients. We performed a systematic review and meta-analysis examining this association.

METHODS

A comprehensive search of the PubMed, EMBASE and Cochrane Library databases was performed to identify relevant literature. Random-effects models were applied to calculate the pooled odds ratio [OR] and relative risk [RR] with corresponding 95% confidence intervals [CIs] among case-control and cohort studies.

RESULTS

Eleven cohort and 16 case-control studies involving 95397 patients were included in this study. Overall, the use of thiopurines was associated with a reduced risk of colorectal neoplasia both in case-control [OR = 0.49, 95% CI: 0.34-0.70] and cohort studies [RR = 0.96, 95% CI: 0.94-0.98]. Moreover, a protective effect of thiopurines against advanced neoplasia [high-grade dysplasia and cancer] [OR = 0.51, 95% CI: 0.31-0.84 for case-control studies; RR = 0.96, 95% CI: 0.94-0.98 for cohort studies] and colorectal cancer [CRC] [OR = 0.56, 95% CI: 0.34-0.93 for case-control studies; RR = 0.96, 95% CI: 0.94-0.98 for cohort studies] was also observed. Furthermore, when the analysis was conducted on patients at a high risk for colorectal neoplasia, the chemopreventive effect was confirmed in patients with long disease duration [> 8 years] but not in those with extensive colitis or primary sclerosing cholangitis.

CONCLUSIONS

This study demonstrated that thiopurine use was associated with a reduced risk of colorectal neoplasia, advanced neoplasia and CRC in IBD patients, especially those with long disease duration [> 8 years].

Chemopreventive effects of 5-aminosalicylic acid on inflammatory bowel disease-associated colorectal cancer and dysplasia: a systematic review with meta-analysis

Background and Aims

The chemopreventive effect of 5-aminosalicylic acid (5-ASA) in patients with inflammatory bowel disease (IBD) has been widely studied; however, the results remain conflicting. The aim of this study was to systematically review the literature and update evidence concerning effects of 5-ASA on the risk of colorectal cancer (CRC) and dysplasia (Dys) in patients with ulcerative colitis (UC) or Crohn's disease (CD).

Results

5-ASA showed a chemopreventive effect against CRC/Dys in IBD patients (OR = 0.58, 95% CI: 0.45−0.75). However, this effect was significant only in clinical-based studies (OR = 0.51; 95% CI: 0.39−0.65), but not in population-based studies (OR = 0.71; 95% CI: 0.46−1.09). Moreover, this effect was noticeable in patients with UC (OR = 0.46, 95% CI: 0.34−0.61), but not in CD (OR = 0.66, 95% CI: 0.42−1.03), and on the outcome of CRC (OR = 0.54, 95% CI: 0.39−0.74), but not Dys (OR = 0.47; 95% CI: 0.20−1.10). In IBD patients, mesalazine dosage ≥ 1.2 g/day showed greater protective effects against CRC/Dys than dosages < 1.2 g/day. However, Sulphasalazine therapy did not show any noticeable protective function regardless of the dosage administered.

Materials and Methods

We performed a systematic review with a meta-analysis of 26 observational studies involving 15,460 subjects to evaluate the risks of developing CRC and Dys in IBD patients receiving 5-ASA treatment. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each evaluation index.

Conclusions

5-ASA has a chemopreventive effect on CRC (but not Dys) in IBD patients. Moreover, UC patients can benefit more from 5-ASA than CD patients. Mesalazine maintenance dosage ≥ 1.2 g/day is an effective treatment for reducing CRC risk in IBD patients.

Tea Polysaccharide Prevents Colitis-Associated Carcinogenesis in Mice by Inhibiting the Proliferation and Invasion of Tumor Cells

The imbalance between cell proliferation and apoptosis can lead to tumor progression, causing oncogenic transformation, abnormal cell proliferation and cell apoptosis suppression. Tea polysaccharide (TPS) is the major bioactive component in green tea, it has showed antioxidant, antitumor and anti-inflammatory bioactivities. In this study, the chemoprophylaxis effects of TPS on colitis-associated colon carcinogenesis, especially the cell apoptosis activation and inhibition effects on cell proliferation and invasion were analyzed. The azoxymethane/dextran sulfate sodium (AOM/DSS) was used to induce the colorectal carcinogenesis in mice. Results showed that the tumor incidence was reduced in TPS-treated AOM/DSS mice compared to AOM/DSS mice. TUNEL staining and Ki-67 immunohistochemistry staining showed that the TPS treatment increased significantly the cell apoptosis and decreased cell proliferation among AOM/DSS mice. Furthermore, TPS reduced the expression levels of the cell cycle protein cyclin D1, matrix metalloproteinase (MMP)-2, and MMP-9. In addition, in vitro studies showed that TPS, suppressed the proliferation and invasion of the mouse colon cancer cells. Overall, our findings demonstrated that TPS could be a potential agent in the treatment and/or prevention of colon tumor, which promoted the apoptosis and suppressed the proliferation and invasion of the mouse colon cancer cells via arresting cell cycle progression.

Systematic review with meta-analysis: thiopurines decrease the risk of colorectal neoplasia in patients with inflammatory bowel disease

BACKGROUND

Patients with inflammatory bowel disease (IBD) have a high risk of developing colorectal neoplasia.

AIM

To investigate whether thiopurines can decrease the risk of developing colorectal neoplasia in patients with ulcerative colitis (UC) or Crohn's disease (CD).

METHODS

We conducted a meta-analysis of 24 observational studies involving 76,999 participants to evaluate the risks of developing colorectal neoplasia in IBD patients receiving thiopurine treatment. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the risks of colorectal neoplasia were calculated using a random-effects model.

RESULTS

The overall pooled estimate revealed a protective effect of thiopurine use on colorectal neoplasia in patients with IBD (OR = 0.63, 95% CI 0.46-0.86). The effect was significant in UC patients (OR = 0.67, 95% CI 0.45-0.98), but was not significant in CD patients (OR = 1.06, 95% CI 0.54-2.09). Thiopurines exposure significantly decreased the risk of colorectal cancer (CRC) (OR = 0.65, 95% CI 0.45-0.96) and advanced colorectal neoplasia (CRC and/or high-grade dysplasia) (OR = 0.62, 95% CI 0.44-0.89), but did not decrease the risk of dysplasia alone (OR = 0.90, 95% CI 0.37-2.21). Tendencies towards the protective effect of thiopurines were distinct in clinic-based studies (OR = 0.59, 95% CI 0.42-0.82) and case-control studies (OR = 0.40, 95% CI 0.26-0.62), but not in population-based studies (OR = 0.95, 95% CI 0.55-1.62) and cohort studies (OR = 0.98, 95% CI 0.81-1.18). Interestingly, studies conducted in Europe (OR = 0.48, 95% CI 0.31-0.77), rather than in North America (OR = 0.91, 95% CI 0.67-1.24), showed the protective effect of thiopurines.

CONCLUSIONS

This meta-analysis revealed an antineoplastic effect of thiopurines on colorectal neoplasia in patients with IBD, particularly amongst patients with UC.

Surgical options in the treatment of ulcerative colitis

Children and young adults with ulcerative colitis tend to present with more extensive colonic disease than an adult population. The need for surgical intervention in the pediatric population with ulcerative colitis occurs earlier after diagnosis and has a greater incidence than a comparably matched adult population with an estimated need for colectomy at 5 years following diagnosis of 14-20%. Perhaps, even more than the adult population, there is a desire to restore intestinal continuity for the pediatric patient to achieve as healthy and normal quality of life as possible. With surgery playing such a prominent role in the treatment of ulcerative colitis in this age group, an understanding of the surgical treatment options that are available is important. The surgeon's awareness of the complexities of the different operations associated with proctocolectomy and reestablishing intestinal continuity may help to avoid early complications and minimize the risk of less than ideal long-term outcomes.

Impact of mucosal inflammation on risk of colorectal neoplasia in patients with ulcerative colitis: a systematic review and meta-analysis

BACKGROUND AND AIMS

Long-standing ulcerative colitis is an established risk factor for colorectal neoplasia. A number of observational studies have suggested that evidence of mucosal inflammation (endoscopic or histologic) is associated with a greater risk for colorectal neoplasia than is mucosal healing. Our goal was to systematically analyze the risk of colorectal neoplasia in patients with ulcerative colitis who have ongoing mucosal inflammation to better inform surveillance strategies.

METHODS

We performed a systematic review and meta-analysis of the effect of endoscopic and/or histologic inflammation on the risk of colorectal neoplasia in cohort and case-control studies. Sensitivity analyses for study setting and case definition were performed.

RESULTS

Six studies met the inclusion criteria, incorporating outcomes in 1443 patients. No study used a single validated measure for mucosal inflammation. The pooled odds ratio for colorectal neoplasia was 3.5 (95% confidence interval [CI], 2.6-4.8; P < .001) in those with any mucosal inflammation and 2.6 (95% CI, 1.5-4.5; P = .01) in those with histologic inflammation, when compared with those with mucosal healing. The overall quality of the studies was good.

CONCLUSION

The presence of objective evidence of mucosal inflammation during follow-up in patients with ulcerative colitis is associated with a greater risk of subsequent colorectal neoplasia than in those with mucosal healing. This risk factor should be considered in guidelines on surveillance intervals for these patients.

Danshen improves survival of patients with colon cancer and dihydroisotanshinone I inhibit the proliferation of colon cancer cells via apoptosis and skp2 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Danshen (Salvia miltiorrhiza Bunge) is widely used in traditional Chinese medicine. However, it's definite clinical effect and mechanism on colon carcinoma is unclear.

AIM OF THE STUDY

To test the hypothesis that the protective effect of danshen on colon cancer and discover the bioactive compounds through in vitro study.

MATERIALS AND METHODS

We conducted a nationwide cohort study by using population-based data from the Taiwan National Health Insurance Research Database (NHIRD). The study cohort comprised patients diagnosed with malignant neoplasm of colon (ICD-9-CM codes:153) in catastrophic illness database between January 1, 2000, and December 31, 2010. We used the Kaplan-Meier method to estimate colon [corrected] cancer cumulative incidences. Next, human colon cancer cells (HCT 116 cells and HT29 cells) were used to investigate the effect of dihydroisotanshinone I (DT) on the proliferation and apoptosis of human colon cancer cells and the underlying mechanism through XTT assay and flow cytometry. The in vivo effect of DT treatment was investigated through a xenograft nude mouse model.

RESULTS

In our study, the in vivo protective effect of danshen in the different stage of colon cancer patients was validated through data from the National Health Insurance Research Database in Taiwan. In vitro, we found that dihydroisotanshinone I (DT), a bioactive compound present in danshen, can inhibit the proliferation of colon carcinoma cells, HCT 116 cells and HT-29 cells. Moreover, DT induced apoptosis of colorectal cancer cells. DT also repressed the protein expression of Skp2 (S-Phase Kinase Associated Protein 2) and the mRNA levels of its related gene, Snail1 (Zinc finger protein SNAI1) and RhoA (Ras homolog gene family, member A). In addition, DT also blocked the colon cancer cells recruitment ability of macrophage by decreasing CCL2 secretion in macrophages. DT treatment also significantly inhibited the final tumor volume in a xenograft nude mouse model.

CONCLUSION

Danshen has protective effects in colon cancer patients, which could be attributed to DT through blocking the proliferation of colon cancer cells through apoptosis.

Systematic review with meta-analysis: use of 5-aminosalicylates and risk of colorectal neoplasia in patients with inflammatory bowel disease

BACKGROUND

The relationship of 5-aminosalicylates' use with the risk of colorectal neoplasia in patients with inflammatory bowel disease (IBD) has been the focus of a growing body of research.

AIM

To investigate this association through an updated meta-analysis of observational studies.

METHODS

PubMed, Scopus and major conference proceedings were searched up to December 2016. The identified studies were evaluated for publication bias and heterogeneity. Pooled relative risk (RR) estimates were calculated using random-effect models. Detailed subgroup analyses were performed. The GRADE approach was used to assess the quality of evidence.

RESULTS

Thirty-one independent observational studies including 2137 cases of colorectal neoplasia (of which 76% were cancers) were incorporated. Between-study heterogeneity was moderate, while strong suspicion of small-study effects was raised. The overall analysis revealed a protective association between 5-aminosalicylates' use and colorectal neoplasia (RR = 0.57, 95% CI: 0.45-0.71). When the analysis was stratified according to study design and setting, the association was significant in cohort (RR = 0.65, 95% CI: 0.43-0.99; n = 10) and case-control studies (RR = 0.53, 95% CI: 0.40-0.70; n = 21), population-based (RR = 0.70, 95% CI: 0.52-0.94; n = 12) and hospital-based studies (RR = 0.46, 95% CI: 0.34-0.61; n = 19). Exposure to 5-aminosalicylates was protective against cancer (RR = 0.58, 95% CI: 0.45-0.74) and dysplasia (RR = 0.54, 95% CI: 0.35-0.84). The reduction in colorectal neoplasia risk was strong in ulcerative colitis (RR = 0.50, 95% CI: 0.38-0.64), but nonsignificant in Crohn's disease (RR = 0.76, 95% CI: 0.43-1.33). Mesalazine (mesalamine) use was protective (RR = 0.70, 95% CI: 0.51-0.94) with evidence of a dose-effect. The effect of sulfasalazine was marginally nonsignificant (RR = 0.72, 95% CI: 0.51-1.01).

CONCLUSIONS

Our findings support a potential chemopreventive role of 5-aminosalicylates in IBD. Further, high-quality prospective research is warranted.

Detection and characterization of murine colitis and carcinogenesis by molecularly targeted contrast-enhanced ultrasound

AIM

To study mucosal addressin cellular adhesion molecule-1 (MAdCAM-1) and vascular endothelial growth factor (VEGF)-targeted contrast enhanced ultrasound (CEUS) for the assessment of murine colitis and carcinogenesis.

METHODS

C57BL/6 mice were challenged with 3% dextran sodium-sulfate (DSS) for three, six or nine days to study the development of acute colitis. Ultrasound was performed with and without the addition of unspecific contrast agents. MAdCAM-1-targeted contrast agent was used to detect and quantify MAdCAM-1 expression. Inflammatory driven colorectal azoxymethane (AOM)/DSS-induced carcinogenesis was examined on day 42 and 84 using VEGF-targeted contrast agent. Highly specific tissue echogenicity was quantified using specialized software. Sonographic findings were correlated to tissue staining, western blot analysis and immunohistochemistry to quantify the degree of inflammation and stage of carcinogenesis.

RESULTS

Native ultrasound detected increased general bowel wall thickening that correlated with more progressed and more severe DSS-colitis (healthy mice: 0.3 mm ± 0.03 vs six days DSS: 0.5 mm ± 0.2 vs nine days DSS: 0.6 mm ± 0.2, P < 0.05). Moreover, these sonographic findings correlated well with clinical parameters such as weight loss (r² = 0.74) and histological damage (r² = 0.86) (P < 0.01). In acute DSS-induced murine colitis, CEUS targeted against MAdCAM-1 detected and differentiated stages of mild, moderate and severe colitis via calculation of mean pixel contrast intensity in decibel (9.6 dB ± 1.6 vs 12.9 dB ± 1.4 vs 18 dB ± 3.33, P < 0.05). Employing the AOM/DSS-induced carcinogenesis model, tumor development was monitored by CEUS targeted against VEGF and detected a significantly increased echogenicity in tumors as compared to adjacent healthy mucosa (healthy mucosa, 1.6 dB ± 1.4 vs 42 d, 18.2 dB ± 3.3 vs 84 d, 18.6 dB ± 4.9, P < 0.01). Tissue echogenicity strongly correlated with histological analysis and immunohistochemistry findings (VEGF-positive cells in 10 high power fields of healthy mucosa: 1 ± 1.2 vs 42 d after DSS start: 2.4 ± 1.6 vs 84 d after DSS start: 3.5 ± 1.3, P < 0.01).

CONCLUSION

Molecularly targeted CEUS is a highly specific and non-invasive imaging modality, which characterizes murine intestinal inflammation and carcinogenesis in vivo.

Inflammatory hypoxia induces syndecan-2 expression through IL-1β-mediated FOXO3a activation in colonic epithelia

Chronic inflammation is known to be a key causative factor in tumor progression, but we do not yet fully understand the molecular mechanism through which inflammation leads to cancer. Here, we report that the dextran sulfate sodium (DSS)-induced mouse model of chronic colitis is associated with increases in the serum level of IL-1β and the colonic epithelial expression of the cell-surface heparan sulfate proteoglycan, syndecan-2. We further show that IL-1β stimulated the transcription of syndecan-2 via NF-κB-dependent FOXO3a activation in CCD841CoN normal colonic epithelial cells and early-stage HT29 colon cancer cells. Inflammatory hypoxia was observed in the colonic epithelia of mice with chronic colitis, suggesting that hypoxic stress is involved in the regulation of syndecan-2 expression. Consistently, experimental inflammatory hypoxia induced hypoxia inducible factor-1α-dependent FOXO3a expression and the p38 MAPK-mediated nuclear localization of FOXO3a. FOXO3a directly mediated syndecan-2 expression in both cell lines and the colonic epithelia of mice with DSS-induced colitis. Moreover, syndecan-2 expression was detected in azoxymethane/DSS-induced colon tumors. Together, these data demonstrate that inflammatory hypoxia up-regulates syndecan-2 via the IL-1β-NF-κB-FOXO3a pathway. These findings provide new mechanistic insights into inflammatory hypoxia-mediated syndecan-2 expression to connect chronic inflammation and the development of colon cancer.-Choi, S., Chung, H., Hong, H., Kim, S. Y., Kim, S.-E., Seoh, J.-Y., Moon, C. M., Yang, E. G., Oh, E.-S. Inflammatory hypoxia induces syndecan-2 expression through IL-1β-mediated FOXO3a activation in colonic epithelia.

Microscopic Colitis: What Do We Know About Pathogenesis?

Microscopic colitis (MC) is a common cause of chronic diarrhea. The 2 most frequent forms of MC are collagenous colitis and lymphocytic colitis. Over the past years, the incidence and prevalence of microscopic colitis are rising and this is largely attributed to a greater awareness, and concomitantly an increasing number of diagnoses. Patients with microscopic colitis report watery, nonbloody diarrhea of chronic course, abdominal pain, weight loss, and fatigue that may impair patient's health-related quality of life. The underlying mechanisms involved in the pathogenesis of microscopic colitis remain unspecified but is probably multifactorial. Collagenous colitis and lymphocytic colitis may represent specific mucosal responses to different luminal agents in predisposed individuals, resulting in an uncontrolled immune response. Genetic predisposition, altered modulation of cytokines and miRNAs, and aberrant response to drugs seem to be involved in the development of MC. Despite the progress of knowledge, still many questions remain unsolved regarding the etiology, pathophysiology, and optimal management of MC. This review gives an update on the immunological aspects of collagenous colitis and lymphocytic colitis.

Diagnostic imaging advances in murine models of colitis

Inflammatory bowel diseases (IBD) such as Crohn’s disease and ulcerative colitis are chronic-remittent inflammatory disorders of the gastrointestinal tract still evoking challenging clinical diagnostic and therapeutic situations. Murine models of experimental colitis are a vital component of research into human IBD concerning questions of its complex pathogenesis or the evaluation of potential new drugs. To monitor the course of colitis, to the present day, classical parameters like histological tissue alterations or analysis of mucosal cytokine/chemokine expression often require euthanasia of animals. Recent advances mean revolutionary non-invasive imaging techniques for in vivo murine colitis diagnostics are increasingly available. These novel and emerging imaging techniques not only allow direct visualization of intestinal inflammation, but also enable molecular imaging and targeting of specific alterations of the inflamed murine mucosa. For the first time, in vivo imaging techniques allow for longitudinal examinations and evaluation of intra-individual therapeutic response. This review discusses the latest developments in the different fields of ultrasound, molecularly targeted contrast agent ultrasound, fluorescence endoscopy, confocal laser endomicroscopy as well as tomographic imaging with magnetic resonance imaging, computed tomography and fluorescence-mediated tomography, discussing their individual limitations and potential future diagnostic applications in the management of human patients with IBD.

Prognostic significance of the pre-chemotherapy lymphocyte-to-monocyte ratio in patients with previously untreated metastatic colorectal cancer receiving FOLFOX chemotherapy

Background

As a surrogate marker of systemic inflammation, the lymphocyte-to-monocyte ratio (LMR) is an independent prognostic factor for various malignancies. This study investigated the prognostic significance of the pre-chemotherapy LMR in patients with previously untreated metastatic colorectal cancer (mCRC) receiving chemotherapy.

Methods

The present study included newly diagnosed mCRC patients treated between January 2005 and December 2013 with FOLFOX chemotherapy, specifically oxaliplatin 180 mg/m² on day 1, with leucovorin 400 mg/m² administered as a 2-hour infusion before the administration of 5-fluorouracil 400 mg/m² as an intravenous bolus injection, and 5-fluorouracil 2400 mg/m² as a 46-h infusion immediately after 5-fluorouracil bolus injection. The LMR was calculated as the absolute count of lymphocytes divided by the absolute count of monocytes. COX proportional hazards analysis was performed to evaluate the association of LMR with survival outcomes.

Results

A total of 488 patients were included. Patients with high pre-chemotherapy LMR experienced significant improvements in progression-free survival (PFS, 9.2 vs. 7.6 months, P < 0.001) and overall survival (OS, 19.4 vs. 16.6 months, P < 0.001) compared with patients with low pre-chemotherapy LMR. Subsequent COX multivariate analysis showed that high pre-chemotherapy LMR (≥3.11) was an independent favorable prognostic factor for PFS and OS. Additionally, patients whose LMR remained high (high–high subgroup), increased (low–high subgroup), or decreased (high–low subgroup) following chemotherapy showed better results in terms of PFS and OS than patients whose LMR remained low (low–low subgroup) after chemotherapy.

Conclusions

For patients with previously untreated mCRC receiving FOLFOX chemotherapy, an elevated pre-chemotherapy LMR is an independent favorable prognostic factor for PFS and OS, and changes in the LMR before and after chemotherapy seem to predict the benefit of chemotherapy.

Ulcerative Colitis-associated Cancer/Dysplasia Detected Using Surveillance Colonoscopy Performed in the Clinical Remission Phase: A Report of Five Cases

We herein report five cases of ulcerative colitis-associated cancer/dysplasia. Although clinical remission had been achieved in all patients, mucosal inflammation had been resolved in only one patient. Thus, in order to prevent cancer from developing, appropriate medical therapy aiming not only to relieve the clinical symptoms, but also to suppress chronic inflammation appears to be necessary. Moreover, cancer occurred as early as 4 years after the diagnosis in one patient. In patients without complete resolution of mucosal inflammation, careful surveillance colonoscopy should be initiated in the early phase.

Site-Specific MicroRNA Expression May Lead to Different Subtypes in Ulcerative Colitis

Background and Aim

Ulcerative Colitis (UC) is a type of inflammatory bowel disease, considered as an important disease of gastrointestinal tract having a huge impact on the health of the patient. Prolonged inflammation of colon in UC patients increases the risk of developing colorectal cancer. MiRNA are reported as a connecting link between inflammation and cancer. Differential miRNA expression is reported in Crohn’s disease (CD) patients involving various regions of the gastrointestinal tract. The current study was performed to dissect out the site specific miRNA expression in the colon biopsy samples of UC patients from Northern India.

Methods

Biopsy samples were collected from UC patients and healthy controls from Rectosigmoid Area (RS) and Ascending Colon (AC). MiRNA expression was compared between patients with RS and AC using a microarray platform. Differential expression was further validated by Real Time PCR analysis. Demographic and pathological data of UC -associated CRC patients was collected from the hospital database and analyzed for assessing the site of cancer.

Results

Upon analysis of data generated on a microarray platform and qRT PCR revealed that the expression of six miRNAs hsa-miR-146b-5p, hsa-miR-335-3p, hsa-miR-342-3p, hsa-miR-644b-3p, hsa-miR-491-3p, hsa-miR-4732-3p were downregulated in patients where RS was involved as compared to AC. The expression of hsa-miR-141-3p was upregulated in patients where RS region was involved as compared to AC. Analysis of the registered UC patient’s database from the hospital revealed that the site of CRC was predomimnantly the rectosigmoid region of the colon in most of the cases.

Conclusion

This is the first study to show the differential expression of miRNA involving different sites of colon in UC patients. Taking our data and previous reports into consideration, we propose that differential miRNA expression during UC perhaps contribute in the development of UC-associated CRC at the rectosigmoid area.

Silicone implants and lymphoma: The role of inflammation

The risk of hematological malignancies is mainly determined by genetic background, age, sex, race and ethnicity, geographic location, exposure to certain chemicals and radiation; along with the more recently proposed immune factors such as chronic inflammation, immunodeficiencies, autoimmunity, and infections. Paradigmatic examples include the development of lymphoma in Sjögren's syndrome and Hashimoto thyroiditis, gastric MALT lymphoma in Helicobacter pylori infection, or lymphomas associated with infections by Epstein-Barr virus, human herpes virus 8 (HHV 8) and leukemia/lymphoma virus 1 (HTLV-1). A growing number of reports indicates an increased risk of lymphoma, particularly of the anaplastic large cell (ALCL) type. The implants, specifically those used in the past, elicit chronic stimulation of the immune system against the prosthetic material. This is particularly the case in genetically susceptible hosts. We suggest that polyclonal activation may result in monoclonality in those at risk hosts, ultimately leading to lymphoma. We suggest that patients with an inflammatory response against silicone implants be monitored carefully.

Role of high-mobility group box 1 protein in inflammatory bowel disease

High-mobility group box 1 (HMGB1) protein is a nuclear non-histone DNA-binding protein. It is released into the extracellular milieu and mediates inflammatory responses, which contribute to the pathogenesis of numerous inflammatory diseases, including inflammatory bowel disease (IBD). An online search was performed in PubMed and Web of Science databases for articles providing evidence on the role of HMGB1 in IBD. HMGB1 plays an important role in IBD pathogenesis. Application of HMGB1 antagonists reduced inflammatory reactions and ameliorated colitis in rodent models, which may provide new insights into the diagnosis and treatment of IBD.