Early detection of ulcerative colitis-associated colorectal cancer

Identification and Validation of Biomarkers to Predict Early Diagnosis of Inflammatory Bowel Disease and Its Progression to Colorectal Cancer

Inflammatory bowel disease (IBD) has become a common global health problem as prevalence continues to rise. It is often associated with increased risk of colorectal cancer (CRC) development. Limitations in current IBD biomarker-based diagnosis hinder the accuracy of early detection of CRC progression. Therefore, in this study, we proposed the use of transcription factor (TF)-based biomarkers that can potentially detect the transition of IBD to CRC. Various bioinformatic analysis and online database validations, and RT-qPCR validations were performed to identify possible diagnostic TFs. RUNX1 was identified as a promising TF that regulates 106 IBD/CRC-related genes. The incorporation of RUNX1 in combination with currently known IBD biomarkers, FEV + NFKB1 + RELA, achieved a comparable sensitivity and specificity scores of 99% and 87%, respectively, while RUNX1 in combination with known CRC markers, CEA + TIMP1 + CA724 + CA199, achieved a sensitivity and specificity score of 97% and 99%, respectively. Furthermore, a small pilot RT-qPCR-based analysis confirmed a demarcated shift in expression profiles in CA724, CEA, RUNX1 and TIMP1 in IBD patients compared to CRC patients' tissue samples. Specifically, CA724 is noticeably elevated in IBD, while the levels of CEA, RUNX1 with TIMP1 are probable genes that may be employed in discerning IBD progression to CRC. Therefore, these preliminary results once validated in large patient cohorts could potentially have a significant impact on CRC disease stratification, resulting in a more precise prediction for treatment and treatment outcomes, especially in South African patients.

Dopamine β-hydroxylase shapes intestinal inflammation through modulating T cell activation

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic and relapsing disease characterized by immune-mediated dysfunction of intestinal homeostasis. Alteration of the enteric nervous system and the subsequent neuro-immune interaction are thought to contribute to the initiation and progression of IBD. However, the role of dopamine beta-hydroxylase (DBH), an enzyme converting dopamine into norepinephrine, in modulating intestinal inflammation is not well defined.

METHODS

CD4+CD45RBhighT cell adoptive transfer, and 2,4-dinitrobenzene sulfonic acid (DNBS) or dextran sodium sulfate (DSS)-induced colitis were collectively conducted to uncover the effects of DBH inhibition by nepicastat, a DBH inhibitor, in mucosal ulceration, disease severity, and T cell function.

RESULTS

Inhibition of DBH by nepicastat triggered therapeutic effects on T cell adoptive transfer induced chronic mouse colitis model, which was consistent with the gene expression of DBH in multiple cell populations including T cells. Furthermore, DBH inhibition dramatically ameliorated the disease activity and colon shortening in chemically induced acute and chronic IBD models, as evidenced by morphological and histological examinations. The reshaped systemic inflammatory status was largely associated with decreased pro-inflammatory mediators, such as TNF-α, IL-6 and IFN-γ in plasma and re-balanced Th1, Th17 and Tregs in mesenteric lymph nodes (MLNs) upon colitis progression. Additionally, the conversion from dopamine (DA) to norepinephrine (NE) was inhibited resulting in increase in DA level and decrease in NE level and DA/NE showed immune-modulatory effects on the activation of immune cells.

CONCLUSION

Modulation of neurotransmitter levels via inhibition of DBH exerted protective effects on progression of murine colitis by modulating the neuro-immune axis. These findings suggested a promising new therapeutic strategy for attenuating intestinal inflammation.

An inflammation-related subtype classification for analyzing tumor microenvironment and clinical prognosis in colorectal cancer

Background

The inflammatory response plays an essential role in the tumor microenvironment (TME) of colorectal cancer (CRC) by modulating tumor growth, progression, and response to therapy through the recruitment of immune cells, production of cytokines, and activation of signaling pathways. However, the molecular subtypes and risk score prognostic model based on inflammatory response remain to be further explored.

Methods

Inflammation-related genes were collected from the molecular signature database and molecular subtypes were identified using nonnegative matrix factorization based on the TCGA cohort. We compared the clinicopathological features, immune infiltration, somatic mutation profile, survival prognosis, and drug sensitivity between the subtypes. The risk score model was developed using LASSO and multivariate Cox regression in the TCGA cohort. The above results were independently validated in the GEO cohort. Moreover, we explored the biological functions of the hub gene, receptor interacting protein kinase 2 (RIPK2), leveraging proteomics data, in vivo, and in vitro experiments.

Results

We identified two inflammation-related subtypes (inflammation-low and inflammation-high) and have excellent internal consistency and stability. Inflammation-high subtype showed higher immune cell infiltration and increased sensitivity to common chemotherapeutic drugs, while inflammation-low subtype may be more suitable for immunotherapy. Besides, the two subtypes differ significantly in pathway enrichment and biological functions. In addition, the 11-gene signature prognostic model constructed from inflammation-related genes showed strong prognostic assessment power and could serve as a novel prognostic marker to predict the survival of CRC patients. Finally, RIPK2 plays a crucial role in promoting malignant proliferation of CRC cell validated by experiment.

Conclusions

This study provides new insights into the heterogeneity of CRC and provides novel opportunities for treatment development and clinical decision making.

Ochratoxin A promotes chronic enteritis and early colorectal cancer progression by targeting Rinck signaling

BACKGROUND

Mycotoxins, such as aflatoxin and ochratoxin A (OTA), are found at measurable levels in many staple foods; the health implications of long-term exposure of such toxins are poorly understood. Increasing evidence has confirmed the important role of OTA in upregulation of oxidative stress- and inflammatory response-induced tissue injury. However, it remains unknown whether ochratoxin A can promote chronic colitis and its associated colon cancer (CRC) development, and potential molecular mechanism. Additionally, RING finger-interacting protein with C kinase (RINCK) is a ubiquitin ligase and mediates immune response. Unfortunately, the potential molecular function of RINCK on regulation of colitis is still largely unknown.

PURPOSE

This study aims to provide mechanistic evidence that the role of RINCK in colitis and early colorectal cancer progression in response to OTA treatment via targeting nuclear factor erythroid 2-related factor 2 (NRF2).

METHODS

The Cancer Genome Atlas (TCGA) database, GEO database, human subjects with CC phenotype and CC cell lines were used in this work. Pathological links between OTA, RINCK and treatment of CC are revealed through comprehensive means such as biological information analysis, clinical experiments, RNA-seq, and verification experiments.

RESULTS

In this study, under oxidative stress in setting of colitis, we first identified RINCK as a key regulatory factor and a novel endogenous suppressor of nuclear factor erythroid 2-related factor 2 (NRF2), and we also confirm that RINCK is a NRF2 partner protein that catalyses its ubiquitination and degradation in intestinal epithelial cells (IECs). Notably, in vivo study, pathological phenotypes triggered by OTA pretreatment, accompanied by post-treatment of dextran sulfate sodium (DSS)-induced colitis was significantly mitigated by IEC-specific deficiency of Rinck, IEC-Rinck(KO) and adenovirus-associated virus (AAV)-triggered suppression of Rinck in rodent model, and lentivirus (LV)-mediated downregulation of Rinck (LV-shRinck) in rabbit model, as determined by decreased endogenous reactive oxygen species (ROS) production, pro-inflammatory cytokines contents, improved body weights, reduced survival rates, restored colon length, assuasive DAI and histological scores. Inversely, transgenic mice by IEC-specific Rinck overexpression, IEC-Rinck(OE) accelerated colitis in acute or chronic colitis rodent models and in vitro experiments. Moreover, we found that OTA pretreatment-promoted azoxymethane (AOM)/DSS-induced colitis-associated early colorectal cancer (CRC) was also dramatically reduced by IEC-Rinck(KO), indicated by the decreased tumor number and corresponding KI-67 levels. Clinical samples analysis revealed that RINCK levels were greatly increased in tumor tissues of patients with CRC phenotypes. In parallel, RINCK deletion remarkably retarded the proliferation of colon cancer and tumor growth in vitro and in vivo, respectively. Mechanistically, in response to onset of colitis, RINCK directly interacts with NRF2 and promotes ubiquitin-proteasome degradation via increasing K48-linkage ubiquitin chain, thus leads in suppression of NRF2 nuclear translocation and its downstream cascade inactivation, which retards antioxidant defense.

CONCLUSION

The findings suggested that oral sub-chronic exposure of OTA significantly facilitates DSS-induced colitis and colitis-associated CRC development. These results further elucidated the potential role of RINCK in colitis progression by mediating NRF2 degradation, and could be considered as a therapeutic target for the treatment of such disease.

Microbial metabolites are involved in tumorigenesis and development by regulating immune responses

The human microbiota is symbiotic with the host and can create a variety of metabolites. Under normal conditions, microbial metabolites can regulate host immune function and eliminate abnormal cells in a timely manner. However, when metabolite production is abnormal, the host immune system might be unable to identify and get rid of tumor cells at the early stage of carcinogenesis, which results in tumor development. The mechanisms by which intestinal microbial metabolites, including short-chain fatty acids (SCFAs), microbial tryptophan catabolites (MTCs), polyamines (PAs), hydrogen sulfide, and secondary bile acids, are involved in tumorigenesis and development by regulating immune responses are summarized in this review. SCFAs and MTCs can prevent cancer by altering the expression of enzymes and epigenetic modifications in both immune cells and intestinal epithelial cells. MTCs can also stimulate immune cell receptors to inhibit the growth and metastasis of the host cancer. SCFAs, MTCs, bacterial hydrogen sulfide and secondary bile acids can control mucosal immunity to influence the occurrence and growth of tumors. Additionally, SCFAs, MTCs, PAs and bacterial hydrogen sulfide can also affect the anti-tumor immune response in tumor therapy by regulating the function of immune cells. Microbial metabolites have a good application prospect in the clinical diagnosis and treatment of tumors, and our review provides a good basis for related research.

Differential Gene Expression of Checkpoint Markers and Cancer Markers in Mouse Models of Spontaneous Chronic Colitis

The presence of checkpoint markers in cancer cells aids in immune escape. The identification of checkpoint markers and early cancer markers is of utmost importance to gain clarity regarding the relationship between colitis and progressive inflammation leading to cancer. Herein, the gene expression levels of checkpoint makers, cancer-related pathways, and cancer genes in colon tissues of mouse models of chronic colitis (Winnie and Winnie-Prolapse mice) using next-generation sequencing are determined. Winnie mice are a result of a Muc2 missense mutation. The identification of such genes and their subsequent expression and role at the protein level would enable novel markers for the early diagnosis of cancer in IBD patients. The differentially expressed genes in the colonic transcriptome were analysed based on the Kyoto Encyclopedia of Genes and Genomes pathway. The expression of several oncogenes is associated with the severity of IBD, with Winnie-Prolapse mice expressing a large number of key genes associated with development of cancer. This research presents a number of new targets to evaluate for the development of biomarkers and therapeutics.

Prevention of Colitis-Associated Cancer via Oral Administration of M13-Loaded Lipid Nanoparticles

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease, is known to increase the risk of colitis-associated cancer (CAC). CAC has been found to be unresponsive to standard chemotherapy regimens, and the current treatments do not utilize effective small-molecule drugs and colon-targeted delivery systems. Previous studies indicated that the M13-nano-liposome (NL) formulation can effectively target the colon and reshape the gut microbiota in ex vivo cultures, generating altered microbial metabolites that can efficiently prevent chronic UC. In this study, we tested the cancer cell uptake ability of the NL formulation and investigated the potential of the M13-NL formulation to prevent CAC in the azoxymethane (AOM)-exposed IL10-/- mouse model. Our findings demonstrate that oral administration of M13-NL prevents tumor development in AOM-exposed IL10-/- mice, suggesting that M13-NL is a promising oral drug formulation for preventing CAC.

Resistin, Elastase, and Lactoferrin as Potential Plasma Biomarkers of Pediatric Inflammatory Bowel Disease Based on Comprehensive Proteomic Screens

Inflammatory bowel disease (IBD) is an immune-mediated chronic inflammation of the intestine, which can present in the form of ulcerative colitis (UC) or as Crohn's disease (CD). Biomarkers are needed for reliable diagnosis and disease monitoring in IBD, especially in pediatric patients. Plasma samples from a pediatric IBD cohort were interrogated using an aptamer-based screen of 1322 proteins. The elevated biomarkers identified using the aptamer screen were further validated by ELISA using an independent cohort of 76 pediatric plasma samples, drawn from 30 CD, 30 UC, and 16 healthy controls. Of the 1322 proteins screened in plasma from IBD patients, 129 proteins were significantly elevated when compared with healthy controls. Of these 15 proteins had a fold change greater than 2 and 28 proteins had a fold change >1.5. Neutrophil and extracellular vesicle signatures were detected among the elevated plasma biomarkers. When seven of these proteins were validated by ELISA, resistin was the only protein that was significantly higher in both UC and CD (p < 0.01), with receiver operating characteristic area under the curve value of 0.82 and 0.77, respectively, and the only protein that exhibited high sensitivity and specificity for both CD and UC. The next most discriminatory plasma proteins were elastase and lactoferrin, particularly for UC, with receiver operating characteristic area under the curve values of 0.74 and 0.69, respectively. We have identified circulating resistin, elastase, and lactoferrin as potential plasma biomarkers of IBD in pediatric patients using two independent diagnostic platforms and two independent patient cohorts.

Mexican Colorectal Cancer Research Consortium (MEX-CCRC): Etiology, Diagnosis/Prognosis, and Innovative Therapies

In 2013, recognizing that Colorectal Cancer (CRC) is the second leading cause of death by cancer worldwide and that it was a neglected disease increasing rapidly in Mexico, the community of researchers at the Biomedicine Research Unit of the Facultad de Estudios Superiores Iztacala from the Universidad Nacional Autónoma de México (UNAM) established an intramural consortium that involves a multidisciplinary group of researchers, technicians, and postgraduate students to contribute to the understanding of this pathology in Mexico. This article is about the work developed by the Mexican Colorectal Cancer Research Consortium (MEX-CCRC): how the Consortium was created, its members, and its short- and long-term goals. Moreover, it is a narrative of the accomplishments of this project. Finally, we reflect on possible strategies against CRC in Mexico and contrast all the data presented with another international strategy to prevent and treat CRC. We believe that the Consortium's characteristics must be maintained to initiate a national strategy, and the reported data could be useful to establish future collaborations with other countries in Latin America and the world.

Effect of Comorbidities on Inflammatory Bowel Disease-Related Colorectal Cancer: A Nationwide Inpatient Review

Introduction 

The risk of inflammatory bowel disease-associated colorectal cancer (IBD-CRC) is known to increase with primary sclerosing cholangitis (PSC) and a family history of CRC. However, the impact of comorbidities such as liver disease, obesity, diabetes, chronic lung, heart, and renal disease, and psychiatric illness on the risk of IBD-CRC remains unclear. We evaluated the effect of these comorbidities on the risk of IBD-CRC.

Methods

A retrospective review from 2009 to 2014 was conducted using the National Inpatient Sample data for adults 18 years and older. Patients with IBD (360,892), of whom 2,831 had CRC were identified using the International Classification of Diseases, Ninth Revision codes (ICD-9). Data on comorbidities were also obtained. Adjusted odds ratios (aOR) and confidence intervals (CI) were computed via logistic regression to evaluate the effect of comorbidities on the risk of IBD-CRC; the p-value was set at <0.05.

Results

The mean age of IBD patients in this study was 52.36±0.03. A majority of the patients with IBD-CRC were white and were significantly older compared to those without cancer (60 vs 52 years, p<0.05). The risk of colon cancer in IBD was increased by having a non-cholestatic liver disease (aOR 1.51, CI 1.23-1.86, p<0.01). Also, patients younger than 50 years with liver disease were at an increased risk of IBD-associated colon cancer in comparison to older patients (aOR 1.83 vs 1.34, p<0.05). Notably, diabetes, chronic pulmonary disease, renal failure, psychiatric illnesses, and rheumatoid diseases, were inversely associated with the risk of IBD-CRC (p<0.05). After stratifying by IBD subtypes, non-cholestatic liver disease was still independently associated with a higher risk for colon cancer in patients with ulcerative colitis or Crohn's disease (ulcerative colitis: aOR 1.43, CI 1.08-1.89; Crohn's disease: aOR 1.46, CI 1.10-2.00).

Conclusions

Patients with IBD who have non-cholestatic liver disease might have a higher risk for colon cancer, even at a younger age. These patients may require close colon cancer surveillance.

The Role and Interactions of Programmed Cell Death 4 and its Regulation by microRNA in Transformed Cells of the Gastrointestinal Tract

Data from GLOBOCAN 2020 estimates that there were 19.3 million new cases of cancer and 10.0 million cancer-related deaths in 2020 and that this is predicted to increase by 47% in 2040. The combined burden of cancers of the gastrointestinal (GI) tract, including oesophageal-, gastric- and colorectal cancers, resulted in 22.6% of the cancer-related deaths in 2020 and 18.7% of new diagnosed cases. Understanding the aetiology of GI tract cancers should have a major impact on future therapies and lessen this substantial burden of disease. Many cancers of the GI tract have suppression of the tumour suppressor Programmed Cell Death 4 (PDCD4) and this has been linked to the expression of microRNAs which bind to the untranslated region of PDCD4 mRNA and either inhibit translation or target the mRNA for degradation. This review highlights the properties of PDCD4 and documents the evidence for the regulation of PDCD4 expression by microRNAs in cancers of the GI tract.

Berberine as a Potential Agent for the Treatment of Colorectal Cancer

Colorectal cancer (CRC) is one of the most commonly diagnosed and deadly malignancies worldwide. The incidence of CRC has been increasing, especially in young people. Although great advances have been made in managing CRC, the prognosis is unfavorable. Numerous studies have shown that berberine (BBR) is a safe and effective agent presenting significant antitumor effects. Nevertheless, the detailed underlying mechanism in treating CRC remains indistinct. In this review, we herein offer beneficial evidence for the utilization of BBR in the management and treatment of CRC, and describe the underlying mechanism(s). The review emphasizes several therapeutic effects of BBR and confirms that BBR could suppress CRC by modulating gene expression, the cell cycle, the inflammatory response, oxidative stress, and several signaling pathways. In addition, BBR also displays antitumor effects in CRC by regulating the gut microbiota and mucosal barrier function. This review emphasizes BBR as a potentially effective and safe drug for CRC therapy.

From inflammatory bowel disease to colorectal cancer: what's the role of miRNAs?

Inflammatory Bowel Disease (IBD) is a chronic inflammatory disease with relapse and remission periods. Ulcerative colitis and Crohn's disease are two major forms of the disease. IBD imposes a lot of sufferings on the patient and has many consequences; however, the most important is the increased risk of colorectal cancer, especially in patients with Ulcerative colitis. This risk is increased with increasing the duration of disease, thus preventing the progression of IBD to cancer is very important. Therefore, it is necessary to know the details of events contributed to the progression of IBD to cancer. In recent years, the importance of miRNAs as small molecules with 20-22 nucleotides has been recognized in pathophysiology of many diseases, in which IBD and colorectal cancer have not been excluded. As a result, the effectiveness of these small molecules as therapeutic target is hopefully confirmed. This paper has reviewed the related studies and findings about the role of miRNAs in the course of events that promote the progression of IBD to colorectal carcinoma, as well as a review about the effectiveness of some of these miRNAs as therapeutic targets.

hucMSC-Derived Exosomes Alleviate the Deterioration of Colitis via the miR-146a/SUMO1 Axis

Human umbilical cord mesenchymal stem cell-derived exosome (hucMSC-Ex) plays an important role in tissue repair and immunomodulation, leading to the mitigation of inflammatory bowel disease. However, the preventive function of hucMSC-Ex in the onset and progression of colitis-associated colon cancer (CAC) is poorly understood. In the current study, dextran sodium sulfate/azoxymethane-induced colitis mouse model was established, and the mice disease activity index, body weight, colon length, tumor counts, survival curve, tissue H&E/immunohistochemistry, and cytokines expression were analyzed to evaluate the effects of hucMSC-Ex on CAC. In addition, miR-146a mimics were transfected into colonic epithelial cells (fetal human cells) to evaluate their role in the hucMSC-Ex-mediated regulation of SUMO1. The results showed that hucMSC-Ex inhibits the expression of SUMO1 to reduce the process of CAC progression. Further analysis indicated that miR-146a targets and inhibits SUMO1 expression and its binding to β-catenin. In conclusion, our findings showed that hucMSC-Ex is effective in alleviating the deterioration of colitis via the miR-146a-mediated inhibition of SUMO1, which is crucial in this disease process.

Current Advances in Coptidis Rhizoma for Gastrointestinal and Other Cancers

Cancer is a serious disease with an increasing number of reported cases and high mortality worldwide. Gastrointestinal cancer defines a group of cancers in the digestive system, e.g., liver cancer, colorectal cancer, and gastric cancer. Coptidis Rhizoma (C. Rhizoma; Huanglian, in Chinese) is a classical Chinese medicinal botanical drug for the treatment of gastrointestinal disorders and has been shown to have a wide variety of pharmacological activity, including antifungal, antivirus, anticancer, antidiabetic, hypoglycemic, and cardioprotective effects. Recent studies on C. Rhizoma present significant progress on its anticancer effects and the corresponding mechanisms as well as its clinical applications. Herein, keywords related to C. Rhizoma, cancer, gastrointestinal cancer, and omics were searched in PubMed and the Web of Science databases, and more than three hundred recent publications were reviewed and discussed. C. Rhizoma extract along with its main components, berberine, palmatine, coptisine, magnoflorine, jatrorrhizine, epiberberine, oxyepiberberine, oxyberberine, dihydroberberine, columbamine, limonin, and derivatives, are reviewed. We describe novel and classic anticancer mechanisms from various perspectives of pharmacology, pharmaceutical chemistry, and pharmaceutics. Researchers have transformed the chemical structures and drug delivery systems of these components to obtain better efficacy and bioavailability of C. Rhizoma. Furthermore, C. Rhizoma in combination with other drugs and their clinical application are also summarized. Taken together, C. Rhizoma has broad prospects as a potential adjuvant candidate against cancers, making it reasonable to conduct additional preclinical studies and clinical trials in gastrointestinal cancer in the future.

Commentary on: Screening of immunosuppressive cells from colorectal adenocarcinoma and identification of prognostic markers

Colorectal adenocarcinoma (COAD) is one subtype of colorectal carcinoma (CRC), whose development is associated with genetics, inappropriate immune response, and environmental factors. Although significant advances have been made in the treatment of COAD, the mortality rate remains high. It is a pressing need to explore novel therapeutic targets of COAD. Available evidence indicated that immune cell infiltration was correlated with cancer prognosis. To reveal the roles of immune cells in the COAD prognosis, a study published in Bioscience Reports by Li et al. (Bioscience Reports (2021) 41, https://doi.org/10.1042/BSR20203496) analyzed data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) dataset. It demonstrated a beneficial effect of Th17 cells in COAD prognosis. In addition, six hub genes (KRT23, ULBP2, ASRGL1, SERPINA1, SCIN, and SLC28A2) were identified to correlate with Th17 cells and COAD prognosis, suggesting one new therapy strategy and some predictive biomarkers of COAD. These findings reported by Li et al. may pave one way to explore the molecular mechanism of COAD further.

Inflammatory Bowel Disease-Associated Colorectal Cancer: Translational Risks from Mechanisms to Medicines

The cumulative impact of chronic inflammation in patients with inflammatory bowel diseases predisposes to the development of inflammatory bowel disease-associated colorectal cancer [IBD-CRC]. Inflammation can induce mutagenesis, and the relapsing-remitting nature of this inflammation, together with epithelial regeneration, may exert selective pressure accelerating carcinogenesis. The molecular pathogenesis of IBD-CRC, termed the 'inflammation-dysplasia-carcinoma' sequence, is well described. However, the immunopathogenesis of IBD-CRC is less well understood. The impact of novel immunosuppressive therapies, which aim to achieve deep remission, is mostly unknown. Therefore, this timely review summarizes the clinical context of IBD-CRC, outlines the molecular and immunological basis of disease pathogenesis, and considers the impact of novel biological therapies.

Colorectal Dysplasia and Cancer Surveillance in Ulcerative Colitis

Ulcerative colitis (UC) is a risk factor for the development of inflammation-associated dysplasia or colitis-associated neoplasia (CAN). This transformation results from chronic inflammation, which induces changes in epithelial proliferation, survival, and migration via the induction of chemokines and cytokines. There are notable differences in genetic mutation profiles between CAN in UC patients and sporadic colorectal cancer in the general population. Colonoscopy is the cornerstone for surveillance and management of dysplasia in these patients. There are several modalities to augment the quality of endoscopy for the better detection of dysplastic or neoplastic lesions, including the use of high-definition white-light exam and image-enhanced colonoscopy, which are described in this review. Clinical practice guidelines regarding surveillance strategies in UC have been put forth by various GI societies, and overall, there is agreement between them except for some differences, which we highlight in this article. These guidelines recommend that endoscopically detected dysplasia, if feasible, should be resected endoscopically. Advanced newer techniques, such as endoscopic mucosal resection and endoscopic submucosal dissection, have been utilized in the treatment of CAN. Surgery has traditionally been the mainstay of treating such advanced lesions, and in cases where endoscopic resection is not feasible, a proctocolectomy, followed by ileal pouch-anal anastomosis, is generally recommended. In this review we summarize the approach to surveillance for cancer and dysplasia in UC. We also highlight management strategies if dysplasia is detected.

Roles of G Protein-Coupled Receptors (GPCRs) in Gastrointestinal Cancers: Focus on Sphingosine 1-Shosphate Receptors, Angiotensin II Receptors, and Estrogen-Related GPCRs

It is well established that gastrointestinal (GI) cancers are common and devastating diseases around the world. Despite the significant progress that has been made in the treatment of GI cancers, the mortality rates remain high, indicating a real need to explore the complex pathogenesis and develop more effective therapeutics for GI cancers. G protein-coupled receptors (GPCRs) are critical signaling molecules involved in various biological processes including cell growth, proliferation, and death, as well as immune responses and inflammation regulation. Substantial evidence has demonstrated crucial roles of GPCRs in the development of GI cancers, which provided an impetus for further research regarding the pathophysiological mechanisms and drug discovery of GI cancers. In this review, we mainly discuss the roles of sphingosine 1-phosphate receptors (S1PRs), angiotensin II receptors, estrogen-related GPCRs, and some other important GPCRs in the development of colorectal, gastric, and esophageal cancer, and explore the potential of GPCRs as therapeutic targets.

Inflammation-Induced Tumorigenesis and Metastasis

Inflammation, especially chronic inflammation, plays a pivotal role in tumorigenesis and metastasis through various mechanisms and is now recognized as a hallmark of cancer and an attractive therapeutic target in cancer. In this review, we discuss recent advances in molecular mechanisms of how inflammation promotes tumorigenesis and metastasis and suppresses anti-tumor immunity in various types of solid tumors, including esophageal, gastric, colorectal, liver, and pancreatic cancer as well as hematopoietic malignancies.

Patients' perception of colonoscopy and acceptance of colonoscopy based IBD related colorectal cancer surveillance

OBJECTIVES

Patients with Inflammatory Bowel Disease (IBD) are at an increased risk of colorectal cancer (CRC). Current surveillance for CRC involves often uncomfortable colonoscopy. To assess IBD patients' perception of colonoscopy and examine preferences for hypothetical alternatives.

METHODS

IBD patients in clinical remission rated acceptable frequency of colonoscopy and hypothetical alternatives to colonoscopy-based surveillance (preference of yearly blood, yearly stool or 5-yearly imaging tests over 5-yearly colonoscopy). Participants rated discomfort of the last colonoscopy was compared with hospital records.

RESULTS

Of 282 patients with recollection of colonoscopy 65.8% rated the discomfort as moderate to severe, which correlated weakly with endoscopists' perception (r = 0.225; p = 0.015). There were no significant differences in patients' or endoscopists' perceptions of discomfort between sedated and unsedated colonoscopies. Undergoing a yearly colonoscopy was acceptable to 49.5%. Experienced discomfort did not correlate with patients' views on acceptable frequency of surveillance colonoscopy. Over 95% of patients would prefer blood, stool, or imaging tests over colonoscopy but nearly half expected sensitivities ≥95%.

CONCLUSION

A large proportion of IBD patients experienced colonoscopy as moderate to severely uncomfortable but would still accept colonoscopy surveillance frequency according to current guidance. Participants expected sensitivities ≥95% for potential alternatives to colonoscopy-based surveillance programs.

EXPERT OPINION

IBD patients frequently experience colonoscopy as uncomfortable but accept colonoscopy as the gold standard for colorectal cancer surveillance. The currently suggested frequencies of surveillance by colonoscopy are acceptable to IBD patients. They do however express a clear preference for non-invasive surveillance techniques. Some promising initial results have been obtained based on faecal or blood sampling. However, these have yet to be tested in large prospective studies to determine their sensitivity and specificity. IBD patients expect these non-invasive tests to meet high standards for sensitivity. In our view it is feasible that analogue to faecal immunochemistry based testing for general population bowel cancer screening non-invasive IBD surveillance techniques will emerge. This could lead to a reduction in the need for colonoscopy to those testing positive on faecal or blood based surveillance.

Chromoendoscopy with targeted biopsies is superior to white-light endoscopy for the long-term follow-up detection of dysplasia in ulcerative colitis patients: a multicenter randomized-controlled trial

Background

Data from single-center experience or small sample-sized studies have shown that chromoendoscopy (CE) might be superior to white-light endoscopy (WLE) for dysplasia surveillance in ulcerative colitis (UC) patients. We performed a prospective randomized trial with a long-term follow-up to compare the detection rate of dysplasia among WLE with targeted biopsies (WLT), WLE with random biopsies (WLR), and dye-based CE with targeted biopsies (CET) in UC patients.

Methods

Patients with long-standing UC were enrolled from 11 medical centers from March 2012 to December 2013 and randomized into three arms (WLT, WLR, and CET). Only high-definition endoscopy was used in all three groups. The patients were followed up by annual endoscopy with biopsies through December 2017.

Results

With a median follow-up time of 55 months, a total of 122 patients with 447 colonoscopies were finally analysed in the per-protocol set: WLT (n = 43), WLR (n = 40), and CET (n = 39). A total of 34 dysplastic lesions were found in 29 colonoscopies of 21 patients. WLR and CET could identify more colonoscopies that diagnosed dysplasia than WLT (8.1% and 9.7% vs 1.9%; P = 0.014 and 0.004, respectively). WLR obtained more biopsied samples than WLT and CET (16.4 ± 5.1 vs 4.3 ± 1.4 and 4.3 ± 1.4; both P < 0.001). During the second half of the follow-up (37 − 69 months), CET could identify more colonoscopies that diagnosed dysplasia than WLT (13.3% vs 1.6%, P = 0.015) and showed a trend for increasing the detection rate compared with WLR (13.3% vs 4.9%, P = 0.107).

Conclusions

For a better outcome of cancer/dysplasia surveillance in patients with long-standing UC, CET appeared to be more effective than WLT and less tedious than WLR. CET was found to be particularly useful when a long-term (>3 years) follow-up was conducted for dysplasia surveillance. The trial was registered on www.chictr.org.cn (ChiCTR1900023689).

The Macrophages-Microbiota Interplay in Colorectal Cancer (CRC)-Related Inflammation: Prognostic and Therapeutic Significance

Tumor-associated macrophages (TAMs) are the main population of myeloid cells infiltrating solid tumors and the pivotal orchestrators of cancer-promoting inflammation. However, due to their exceptional plasticity, macrophages can be also key effector cells and powerful activators of adaptive anti-tumor immunity. This functional heterogeneity is emerging in human tumors, colorectal cancer (CRC) in particular, where the dynamic co-existence of different macrophage subtypes influences tumor development, outcome, and response to therapies. Intestinal macrophages are in close interaction with enteric microbiota, which contributes to carcinogenesis and affects treatment outcomes. This interplay may be particularly relevant in CRC, one of the most prevalent and lethal cancer types in the world. Therefore, both macrophages and intestinal microbiota are considered promising prognostic indicators and valuable targets for new therapeutic approaches. Here, we discuss the current understanding of the molecular circuits underlying the interplay between macrophages and microbiota in CRC development, progression, and response to both conventional therapies and immunotherapies.

Targeting of oncogenic signaling pathways by berberine for treatment of colorectal cancer

Studies indicate that inhibiting a single signaling pathway or one single product of a gene is insufficient for the prevention and treatment of cancer. This is due to the fact that dysregulation must occur in more than 500 genes in order to produce a cancerous phenotype. Despite this evidence, available drugs used for cancer treatment focus on a single target. Meanwhile, berberine as a nutraceutical is capable of targeting various processes involved in tumor development including proliferation, invasion, angiogenesis, and metastasis. In comparison with synthetic agents, berberine is cheaper, safer, and more available. Berberine has shown anti-inflammatory properties which make it an ideal option in order to prevent inflammation-associated cancers. Colorectal cancer is one of the most common cancers all over the world and its incidence is increasing each day. Therefore, further investigations about berberine could be helpful in the discovery of novel agents for preventing and/or treating colorectal cancer. This review emphasizes the studies investigating the roles of berberine in colorectal cancer such as controlling cell signaling pathways, inducing apoptosis, regulating microRNAs, attenuating oxidative stress, and affecting inflammation.

Immunotherapy, Inflammation and Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer type, and third highest in mortality rates among cancer-related deaths in the United States. Originating from intestinal epithelial cells in the colon and rectum, that are impacted by numerous factors including genetics, environment and chronic, lingering inflammation, CRC can be a problematic malignancy to treat when detected at advanced stages. Chemotherapeutic agents serve as the historical first line of defense in the treatment of metastatic CRC. In recent years, however, combinational treatment with targeted therapies, such as vascular endothelial growth factor, or epidermal growth factor receptor inhibitors, has proven to be quite effective in patients with specific CRC subtypes. While scientific and clinical advances have uncovered promising new treatment options, the five-year survival rate for metastatic CRC is still low at about 14%. Current research into the efficacy of immunotherapy, particularly immune checkpoint inhibitor therapy (ICI) in mismatch repair deficient and microsatellite instability high (dMMR-MSI-H) CRC tumors have shown promising results, but its use in other CRC subtypes has been either unsuccessful, or not extensively explored. This Review will focus on the current status of immunotherapies, including ICI, vaccination and adoptive T cell therapy (ATC) in the treatment of CRC and its potential use, not only in dMMR-MSI-H CRC, but also in mismatch repair proficient and microsatellite instability low (pMMR-MSI-L).

Cruel to Be Kind: Epithelial, Microbial, and Immune Cell Interactions in Gastrointestinal Cancers

A plethora of experimental and epidemiological evidence supports a critical role for inflammation and adaptive immunity in the onset of cancer and in shaping its response to therapy. These data are particularly robust for gastrointestinal (GI) cancers, such as those affecting the GI tract, liver, and pancreas, on which this review is focused. We propose a unifying hypothesis according to which intestinal barrier disruption is the origin of tumor-promoting inflammation that acts in conjunction with tissue-specific cancer-initiating mutations. The gut microbiota and its products impact tissue-resident and recruited myeloid cells that promote tumorigenesis through secretion of growth- and survival-promoting cytokines that act on epithelial cells, as well as fibrogenic and immunosuppressive cytokines that interfere with the proper function of adaptive antitumor immunity. Understanding these relationships should improve our ability to prevent cancer development and stimulate the immune system to eliminate existing malignancies.

Potential role of plasma miR-21 and miR-92a in distinguishing between irritable bowel syndrome, ulcerative colitis, and colorectal cancer

AIM

This study aimed to investigate whether plasma miR-21 and miR-92a levels may be used to differentiate between patients with irritable bowel syndrome (IBS), ulcerative colitis (UC), and colorectal cancer (CRC).

BACKGROUND

miRNA expression profiles are well characterized in CRC, but these expression profiles in UC and IBS remain promising. Screening of high-risk individuals for these diseases has substantial clinical benefits.

METHODS

This was a case-control study. We quantified plasma miR-21 and miR-92a expression levels in 100 samples (37 with active UC, 33 with CRC, and 30 with IBS as well as 30 healthy controls) using real-time PCR. Their diagnostic performance for discriminating these diseases was assessed using receiver-operation characteristic curve (AUC-ROC).

RESULTS

The studied miRNAs were differentially expressed among all participated groups. Plasma miR-21 and miR-92a levels exhibited significant upregulation in CRC as compared to IBS, UC, and healthy subjects. Both miRNAs were upregulated in the UC group as compared to IBS and healthy subjects. ROC analysis revealed promising diagnostic performance for miR-21 and miR-92a in discriminating UC from non-UC groups (IBS and healthy subjects) with AUCs of 0.844 and 0.979 respectively. It also distinguished between CRC and UC with AUCs of 0.968 and 0.887 respectively and with reasonable sensitivities and specificities.

CONCLUSION

Circulating miR-21 and miR-92a can be exploited not only as potential noninvasive biomarkers for detection of CRC, but also for differentiation between functional and organic colorectal disorders.

The Role of MicroRNAs upon Epithelial-to-Mesenchymal Transition in Inflammatory Bowel Disease

Increasing evidence suggest the significance of inflammation in the progression of cancer, for example the development of colorectal cancer in Inflammatory Bowel Disease (IBD) patients. Long-lasting inflammation in the gastrointestinal tract causes serious systemic complications and breaks the homeostasis of the intestine, where the altered expression of regulatory genes and miRNAs trigger malignant transformations. Several steps lead from acute inflammation to malignancies: epithelial-to-mesenchymal transition (EMT) and inhibitory microRNAs (miRNAs) are known factors during multistage carcinogenesis and IBD pathogenesis. In this review, we outline the interactions between EMT components and miRNAs that may affect cancer development during IBD.

From Genetics to Epigenetics, Roles of Epigenetics in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a destructive, recurrent, and heterogeneous disease. Its detailed pathogenesis is still unclear, although available evidence supports that IBD is caused by a complex interplay between genetic predispositions, environmental factors, and aberrant immune responses. Recent breakthroughs with regard to its genetics have offered valuable insights into the sophisticated genetic basis, but the identified genetic factors only explain a small part of overall disease variance. It is becoming increasingly apparent that epigenetic factors can mediate the interaction between genetics and environment, and play a fundamental role in the pathogenesis of IBD. This review outlines recent genetic and epigenetic discoveries in IBD, with a focus on the roles of epigenetics in disease susceptibility, activity, behavior and colorectal cancer (CRC), and their potential translational applications.

Rab23 contributes to the progression of colorectal cancer via protein kinase B and extracellular signal-regulated kinase signaling pathways

The role of Ras-related protein Rab23 in tumors has attracted increasing attention in recent years; however, whether it can function as an oncogenic protein remains under debate, and its role in colorectal cancer (CRC) is currently unknown. In the present study, high expression of Rab23 in CRC tissues was confirmed using immunohistochemistry, and high expression of Rab23 in CRC cells (SW1116 and HT29) was confirmed using reverse transcription-polymerase chain reaction and western blot analysis. A positive association of Rab23 with tumor size and advanced clinical stage was confirmed by χ² analysis. In addition, the positive association of Rab23 with poor disease-free survival was confirmed by survival analysis. Cell experiments further demonstrated that overexpression of Rab23 increased the expression of the proliferation marker Ki-67 and the proliferative ability in SW1116 and HT29 cells. Molecular mechanism research revealed that the extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) signaling pathways contributed to the high expression of Ki-67 and increased the proliferative ability induced by Rab23 in CRC cells. In conclusion, the study confirmed the high expression of Rab23 in CRC, and its positive association with CRC progression and poor prognosis. Furthermore, the data demonstrated that Rab23 increased the proliferation of CRC cells via the ERK and AKT signaling pathways. These results suggest that Rab23 may be used as a protein for diagnosis and prognosis prediction in patients with CRC, and is proposed to be a novel therapeutic target for improving the patient outcome.

Reduction of Inflammation and Colon Injury by a Spearmint Phenolic Extract in Experimental Bowel Disease in Mice

Background: Inflammatory Bowel Diseases (IBD) encompasses both Crohn's Disease and Ulcerative Colitis, known to be connected to an enlarged risk for developing colorectal cancer (CRC). Spearmint (Mentha spicata L.) is a Mediterranean plant used as an aromatic agent, and studies have mainly focused on the essential oil suggesting an anti-inflammatory activity. This work aimed to perform a preliminary screening of the in vivo anti-inflammatory effects of a spearmint phenolic extract in an acute inflammation model, in a chronic inflammation model of colitis, and also study the effects in vitro on a colon cancer model. Methods: Spearmint extract was administered to rats of a paw oedema model (induced by carrageenan) and to mice from a TNBS-induced colitis model in parallel with studies using HT-29 CRC cells. Results: Administration of the extract led to reduced paw inflammation, reduction of colon injury and inflammation, with attenuation of histological markers, and reduction of iNOS expression. It repressed the in vitro movement of HT-29 cells in a wound healing assay. Conclusions: These findings suggest that spearmint extract exhibits acute and chronic anti-inflammatory activity and is able to inhibit migration of cancer cells, suggesting a potential role in the supplementary therapy of IBD patients.

The diagnostic efficacy of circulating miRNAs in monitoring the early development of colitis-induced colorectal cancer

Early detection of colorectal cancer and monitoring the progress in colon carcinogenesis stages is essential to reduce mortality. Therefore, there is continuous search for noninvasive biomarkers with high stability and good sensitivity and specificity. miRNAs have attracted attention as promising biomarkers as they are stably expressed in circulation. The aim of our study is to evaluate the aberrant expression of circulating miRNAs during the stepwise progress of colitis-associated colon cancer. This was accomplished through assessing the expression levels of five miRNAs (miR-141, miR-15b, miR-17-3p, miR-21, and miR-29a) in serum and their corresponding tissue samples through the different cycles of colorectal carcinogenesis cascade using the azoxymethane/dextran sulfate sodium murine model. We also compared the diagnostic performance of these selected miRNAs with the conventional tumor biomarkers CEA and CA 19-9. The results of our study revealed that the expression levels of those miRNAs were dynamically changing in accordance with the tumor development state. Moreover, their aberrant expression in serum was statistically correlated with that in tissue. Our data also revealed that serum miR-15b, miR-21, and miR-29a showed the best performance in terms of diagnostic power. Our findings highlight the efficiency of these circulating miRNAs not only for early diagnostics purposes, but also for monitoring progress in the colorectal carcinogenesis process, and therefore encouraging integrating these noninvasive biomarkers into the clinical diagnostic settings beside the traditional diagnostic markers for accurate screening of the early progress of colon carcinogenesis.

Risk factors for colorectal neoplasia in patients with underlying inflammatory bowel disease: a multicenter study

BACKGROUND

This study sought to evaluate the risk factors for the development of colitis-associated neoplasia (CAN) in Chinese patients with inflammatory bowel disease (IBD).

METHODS

IBD patients who developed CAN between 1999 and 2016 were identified from eight medical centers. In addition to initial pathology evaluation, a CAN diagnosis was confirmed by two expert pathologists. Patients with CAN (n = 29) were compared with non-CAN controls (n = 87). Matching was performed for gender and IBD type with a ratio of three controls to one subject.

RESULTS

Of the 29 patients with CAN, 8 (27.6%) had colorectal cancer (CRC), 20 (69.0%) had a final diagnosis of low-grade dysplasia and 1 (3.4%) had high-grade dysplasia. Multivariate analysis revealed that an older age at the time of IBD diagnosis and a longer IBD duration were independent risk factors for the development of CAN, with odds ratios of 1.09 [95% confidence interval (CI): 1.04-1.14, P < 0.001] and 1.14 (95% CI: 1.03-1.27, P = 0.013), respectively. Comparison between IBD patients with CRC and those with dysplasia indicated that the former were older at the time of IBD diagnosis (P = 0.012) and had longer IBD durations (P = 0.019).

CONCLUSIONS

Older age at the time of IBD diagnosis and longer IBD duration were found to be associated with the development of CAN in IBD patients.

Cysteine-derived hydrogen sulfide and gut health: a matter of endogenous or bacterial origin

PURPOSE OF REVIEW

Hydrogen sulfide (H2S) is produced in the gut from cysteine by epithelial cells and by the intestinal microbiota. Initially considered as a toxic gas, the pleiotropic effects of H2S are now recognized, especially in the colonic mucosa. The aim of this review is to present new experimental data indicating that cysteine-derived H2S is emerging as a key regulator of gut health.

RECENT FINDINGS

Cysteine degradation by the microbiota emerged as a dominant pathway for H2S production. Among bacteria producing H2S from cysteine, Fusobacterium appears as a pivotal genus associated with digestive diseases. H2S promotes or alleviates mucosal inflammation, mostly according to its high (high micromolar to millimolar) or low (nanomolar to low micromolar) concentration, respectively. H2S maintains the integrity of the mucus layer when derived from endogenous metabolism but is detrimental for this parameter when produced in excess by gut microbes. In inflammatory bowel diseases, an upregulation of H2S production from cysteine by the gut microbiota is observed concomitantly with a downregulation of enzymes implicated in its mucosal detoxification. In colorectal cancer patients, an upregulation of both endogenous and microbial H2S production from cysteine are observed at tumor site that might contribute to disease progression.

SUMMARY

H2S is a double-edge sword for the intestinal epithelium. This is related to the bell-shaped effects of H2S, with protective effect at low concentration but deleterious effects at higher concentrations. As the gut microbiota produces much more H2S from cysteine than endogenous metabolism, we consider that the bacterial or epithelial source of H2S is a major determinant of its effects for intestinal health.