Dysplastic lesions in inflammatory bowel disease: molecular pathogenesis to morphology

Serrated Polyps in Inflammatory Bowel Disease Indicate a Similar Risk of Metachronous Colorectal Neoplasia as in the General Population

BACKGROUND

The risk of metachronous advanced neoplasia after diagnosing serrated polyps in patients with IBD is poorly understood.

METHODS

A retrospective multicenter cohort study was conducted between 2010 and 2019 at three tertiary centers in Montreal, Canada. From pathology databases, we identified 1587 consecutive patients with serrated polyps (sessile serrated lesion, traditional serrated adenoma, or serrated epithelial change). We included patients aged 45-74 and excluded patients with polyposis, colorectal cancer, or no follow-up. The primary outcome was the risk of metachronous advanced neoplasia (advanced adenoma, advanced serrated lesion, or colorectal cancer) after index serrated polyp, comparing patients with and without IBD.

RESULTS

477 patients with serrated polyps were eligible (mean age 61 years): 37 with IBD, totaling 45 serrated polyps and 440 without IBD, totaling 586 serrated polyps. The median follow-up was 3.4 years. There was no difference in metachronous advanced neoplasia (HR 0.77, 95% CI 0.32-1.84), metachronous advanced adenoma (HR 0.54, 95% CI 0.11-2.67), and metachronous advanced serrated lesion (HR 0.76, 95% CI 0.26-2.18) risk. When comparing serrated polyps in mucosa involved or uninvolved with IBD, both groups had similar intervals from IBD to serrated polyp diagnosis (p > 0.05), maximal therapies (p > 0.05), mucosal inflammation, inflammatory markers, and fecal calprotectin (p > 0.05).

CONCLUSION

The risk of metachronous advanced neoplasia after serrated polyp detection was similar in patients with and without IBD. Serrated polyps in IBD occurred independently of inflammation. This helps inform surveillance intervals for patients with IBD diagnosed with serrated polyps.

Cancer Biology or Ineffective Surveillance? A Multicentre Retrospective Analysis of Colitis-Associated Post-Colonoscopy Colorectal Cancers

BACKGROUND AND AIMS

Inflammatory bowel disease [IBD] is associated with high rates of post-colonoscopy colorectal cancer [PCCRC], but further in-depth qualitative analyses are required to determine whether they result from inadequate surveillance or aggressive IBD cancer evolution.

METHODS

All IBD patients who had a colorectal cancer [CRC] diagnosed between January 2015 and July 2019 and a recent [<4 years] surveillance colonoscopy at one of four English hospital trusts underwent root cause analyses as recommended by the World Endoscopy Organisation to identify plausible PCCRC causative factors.

RESULTS

In total, 61% [n = 22/36] of the included IBD CRCs were PCCRCs. They developed in patients with high cancer risk factors [77.8%; n = 28/36] requiring annual surveillance, yet 57.1% [n = 20/35] had inappropriately delayed surveillance. Most PCCRCs developed in situations where [i] an endoscopically unresectable lesion was detected [40.9%; n = 9/22], [ii] there was a deviation from the planned management pathway [40.9%; n = 9/22], such as service-, clinician- or patient-related delays in acting on a detected lesion, or [iii] lesions were potentially missed as they were typically located within areas of active inflammation or post-inflammatory change [36.4%; n = 8/22].

CONCLUSIONS

IBD PCCRC prevention will require more proactive strategies to reduce endoscopic inflammatory burden, and to improve lesion optical characterization, adherence to recommended surveillance intervals, and patient acceptance of prophylactic colectomy. However, the significant proportion appearing to originate from non-adenomatous-looking mucosa which fail to yield neoplasia on biopsy yet display aggressive cancer evolution highlights the limitations of current surveillance. Emerging molecular biomarkers may play a role in enhancing cancer risk stratification in future clinical practice.

Accuracy of optical diagnosis with narrow band imaging in the surveillance of ulcerative colitis: a prospective study comparing Kudo, Kudo-IBD and NICE classifications

PURPOSE

The diagnostic accuracy of Narrow Band Imaging (NBI) in the endoscopic surveillance of ulcerative colitis (UC) has been disappointing in most trials which used the Kudo classification. We aim to compare the performance of NBI in the lesion characterization of UC, when applied according to three different classifications (NICE, Kudo, Kudo-IBD).

METHODS

In a prospective, real-life study, all visible lesions found during consecutive surveillance colonoscopies with NBI (Exera-II CV-180) for UC were classified as suspected or non-suspected for neoplasia according to the NICE, Kudo and Kudo-IBD criteria. The sensitivity (SE), specificity (SP), positive (+LR) and negative (-LR) likelihood ratios of the three classifications were calculated, using histology as the reference standard.

RESULTS

394 lesions (mean size 6 mm, range 2-40 mm) from 84 patients were analysed. Twenty-one neoplastic (5%), 49 hyperplastic (12%), and 324 inflammatory (82%) lesions were found. The diagnostic accuracy of the NICE, Kudo and Kudo-IBD classifications were, respectively: SE 76%-71%-86%; SP 55-69%-79% (p < 0.05 Kudo-IBD vs. both Kudo and NICE); +LR 1.69-2.34-4.15 (p < 0.05 Kudo-IBD vs. both Kudo and NICE); -LR 0.43-0.41-0.18.

CONCLUSION

The diagnostic accuracy of NBI in the differentiation of neoplastic and non-neoplastic lesions in UC is low if used with conventional classifications of the general population, but it is significantly better with the modified Kudo classification specific for UC.

Association of Periodontal Disease with Activity of Crohn's Disease

INTRODUCTION

Crohn's disease (CD) is a chronic inflammatory granulomatous disease that can affect the entire gastrointestinal tract. It is characterized by various extraintestinal manifestations (EIMs), of which oral manifestations (OMs) are often possible. One of the possible OMs is periodontal disease (PD), a chronic inflammatory condition of the supporting tissues of the teeth. This study aimed to show the existence of a mutual relationship between the clinical activity of PD and the clinical and endoscopic activity of CD.

MATERIALS AND METHODS

One clinical and two endoscopic indexes were used for the assessment of CD activity and clinical attachment loss (CAL), bleeding on probing (BOP), pocket probing depth (PPD), and radiographic bone loss (RBL) in a dental panoramic tomogram to assess PD in CD patients.

RESULTS

A total of 38 patients underwent the entire study process, of which 20 patients had CD and 18 patients had CD and PD. Considering all CD activity scores, there were 26 patients with active disease; half of them had PD, and 85.7% of operated patients had active CD. The values of CAL, PPD, BOP, and RBL were higher in active CD patients than those in remission, except for BOP when comparing to the CDAI score, which was higher in those in remission of CD.

CONCLUSION

The results of this study indicate that there is a connection between the activity of CD and worse conditions of the supporting tissues of the gums in the oral cavity, so it is important to keep in mind the necessity of referring patients with CD to a dentist for timely and adequate therapeutic measures.

MYC overexpression in inflammatory bowel disease-associated conventional dysplasia and association of subsequent low-grade dysplasia in follow-up biopsies

OBJECTIVE

Diagnosis of inflammatory bowel disease (IBD)-associated dysplastic lesions can be challenging. This study aims to evaluate MYC immunohistochemistry (IHC) as a potential biomarker for IBD-associated dysplasia and compare its effectiveness with p53 IHC.

METHODS

The study cohort included resections from 12 IBD patients with carcinoma and concurrent conventional low-grade dysplasia (LGD), as well as biopsies from 21 patients with visible conventional LGD, which were followed up for 2 years with subsequent endoscopic examination. MYC and p53 IHC and MYC-FISH analysis were performed.

RESULTS

Sensitivity for LGD detection was 67% (8/12) and 50% (6/12) for MYC and p53, respectively, but the difference was not statistically significant (p = 0.2207). MYC and p53 overexpression were not always mutually exclusive, nor were they always present simultaneously. Patients who presented dysplasia in subsequent biopsies (7/21) were found to be more likely present with multiple LGD polyps and MYC-overexpressed LGD in the initial biopsies, compared to those without subsequent dysplasia (p < 0.05). These dysplastic lesions were commonly associated with chronic colitis (p = 0.0614). The distribution of LGD sites did not show a significant difference between patients with and without subsequent LGD. In MYC overexpressed cases, homogeneously strong nuclear expression was not identified in all dysplastic epithelial cells, and no MYC amplification was found in these cases by FISH.

CONCLUSION

MYC IHC can complement p53 IHC as an adjunct biomarker for diagnosing IBD-associated conventional LGD and can be used for the prediction of subsequent LGD in the follow-up biopsies combined with endoscopic features.

Incremental Detection Rate of Dysplasia and Sessile Serrated Polyps/Adenomas Using Narrow-Band Imaging and Dye Spray Chromoendoscopy in Addition to High-Definition Endoscopy in Patients with Long-Standing Extensive Ulcerative Colitis: Segmental Tandem Endoscopic Study

High-definition (HD) endoscopy is recommended in surveillance colonoscopy for detecting dysplasia in patients with ulcerative colitis (UC). Dye-spray chromoendoscopy (DCE) and narrow-band imaging (NBI) are often used as adjunctive techniques of white-light endoscopy (WLE) in real-world practice. However, the incremental detection ability of DCE and NBI added to HD-WLE for dysplasia and serrated lesions has not yet been evaluated using tandem endoscopy in patients with long-standing extensive UC. We enrolled patients with extensive UC for >8 years who were in clinical remission (partial Mayo score < 2) at the Samsung Medical Center in Seoul, Republic of Korea. HD-WLE was performed first. Subsequently, HD-NBI and HD-DCE with indigo carmine were performed using the segmental tandem colonoscopy technique. A total of 40 patients were eligible, and data obtained from 33 patients were analyzed. The incremental detection rates (IDRs) for dysplasia and serrated lesions were calculated. HD-WLE detected three dysplasia and five sessile serrated adenomas/polyps (SSAs/Ps). HD-NBI and HD-DCE did not detect additional dysplasia (IDR = 0%; 95% confidence interval (CI): 0-56.2%). HD-NBI identified one missed SSA/P (IDR = 7.7%; 95% CI: 1.4-33.3%), and HD-DCE detected seven missed SSAs/Ps (IDR = 53.9%; 95% CI: 29.1-76.8%). Logistic regression found that HD-DCE increased the detection of SSAs/Ps compared to HD-WLE and/or HD-NBI (odds ratio (OR) = 3.16, 95% CI: 0.83-11.92, p = 0.08). DCE in addition to HD-WLE improved the detection of SSAs/Ps, but not dysplasia, in patients with long-standing extensive UC.

Characteristics of colorectal cancer and use of colonoscopy before colorectal cancer diagnosis among individuals with inflammatory bowel disease: A population-based study

Introduction

There are limited recent data on the characteristics of inflammatory bowel disease (IBD)-associated colorectal cancer (CRC) and the use of colonoscopy prior to CRC diagnosis among persons with IBD. We analyzed IBD-CRC characteristics, survival after IBD-CRC diagnosis and the use of colonoscopy prior to IBD-CRC diagnosis over time.

Methods

We identified individuals with and without IBD from the University of Manitoba IBD Epidemiology Database and CRC from linkage to the Manitoba Cancer Registry. We compared characteristics of IBD-CRC and sporadic-CRC using logistic regression and survival after CRC diagnosis using Cox regression analysis. We assessed rate and predictors of colonoscopy use 5 years to 6 months prior to IBD-CRC.

Results

1,262 individuals with CRC were included (212 IBD-CRC). IBD was associated with an increased risk of death after CRC diagnosis in 2004–2011 (HR 1.89; 95% CI 1.25–2.88) but not in 2012–2017 (HR = 1.002; CI 0.50–2.03). In the 5 years to 6 months prior to IBD-CRC (1989–2018), 51% underwent colonoscopy, which was very similar to IBD without CRC and contrasted to 9% among sporadic CRCs. Exposure to colonoscopy pre IBD-CRC remained stable through the study period (1989–2002 OR = 1.25; CI 0.77–2.01; 2003–2011 OR = 1.21; CI 0.56–1.70; reference 2012–2018). Exposure to colonoscopy pre-IBD-CRC was not associated with improved post-CRC survival.

Conclusion

The risk of death following CRC diagnosis is not impacted by a diagnosis of IBD in recent years. There is a very high proportion of post colonoscopy CRC among IBD-CRC, which has not changed over the years and needs detailed root-cause analysis and interventions.

[A new look at colonic mucosal structural rearrangement and the stages of chronic colitis]

OBJECTIVE

To revise the existing criteria to improve the definition of chronic colitis stages in inflammatory bowel diseases (IBDs).

MATERIAL AND METHODS

A total of 100 cases of IBDs (ulcerative colitis (n=70) and Crohn's disease (n=30) diagnosed in 2017 to 2019 were examined. Thirty patients with colitis were selected for a comparison group, who were assigned to an infective colitis group or a drug-induced colitis one at the final diagnosis.

RESULTS

The sequence of chronic colitis stages was defined from Stage 1 (early changes) to Stage 3, which are characterized by progressive mucosal structural rearrangement. Mainly at Stage 3 that characterizes the final stage of structural rearrangement in the mucous membrane, where dysplastic changes (the onset of tumor transformation) are detected.

CONCLUSION

For the diagnosis of chronic colitis in IBD, it is mandatory to detect mucosal structural rearrangement. Stages 1 and 2 are characterized by early structural changes in the mucous membrane, whereas the process becomes irreversible at Stage 3. The identification of colitis stages is of diagnostic and, undoubtedly, prognostic value.

The Role of the Immune System in IBD-Associated Colorectal Cancer: From Pro to Anti-Tumorigenic Mechanisms

Patients with inflammatory bowel disease (IBD) have increased incidence of colorectal cancer (CRC). IBD-associated cancer follows a well-characterized sequence of intestinal epithelial changes, in which genetic mutations and molecular aberrations play a key role. IBD-associated cancer develops against a background of chronic inflammation and pro-inflammatory immune cells, and their products contribute to cancer development and progression. In recent years, the effect of the immunosuppressive microenvironment in cancer development and progression has gained more attention, mainly because of the unprecedented anti-tumor effects of immune checkpoint inhibitors in selected groups of patients. Even though IBD-associated cancer develops in the background of chronic inflammation which is associated with activation of endogenous anti-inflammatory or suppressive mechanisms, the potential role of an immunosuppressive microenvironment in these cancers is largely unknown. In this review, we outline the role of the immune system in promoting cancer development in chronic inflammatory diseases such as IBD, with a specific focus on the anti-inflammatory mechanisms and suppressive immune cells that may play a role in IBD-associated tumorigenesis.

Follicular Epithelial Dysplasia as Hashimoto Thyroiditis-Related Atypia: a Series of 91 Specimens

Follicular epithelial dysplasia (FED) is described as Hashimoto thyroiditis-related atypia and is thought to be a possible precancerous lesion. Dysplasia as an interface between normal state and carcinoma is described in a wide range of diseases and carcinogenesis chains. On the other hand, inflammation-related atypia and cancerogenesis is also widely studied. In this study, we retrospectively analyzed 91 specimens of thyroid gland surgical resections with FED during a 10-year-period at the university hospital pathology department. The study population consisted of 68 females and 15 males aged between 22 and 86 years. The preoperative cytology diagnoses had mainly been in the indeterminate categories with prevailing AUS/FLUS results in the FED-only group (p = 0.005) and suspicious for malignancy and malignant in the group with FED plus adjacent malignancy. The decision for surgery was malignancy related in 48.2% of the cases. The lesions were sized 0.1-3.5 mm and multifocal in 45.1% of the cases. Immunohistochemically, the atypical cells were cyclin D1-positive in 67.5%, galectin-3 in 72.7%, CK19 in 85.7%, and HBME-1 in 87.0% of cases. In conclusion, FED is suggested to be a pathogenetic link between inflammation-related atypia and papillary carcinoma and thus a premalignant precursor of papillary carcinoma in HT as 36.1% of the specimens contained also papillary carcinoma in the present study. Both histopathological nuclear features and the immunoprofile of FED are widely shared with that of papillary carcinoma.

Canthin-6-one ameliorates TNBS-induced colitis in rats by modulating inflammation and oxidative stress. An in vivo and in silico approach

Canthin-6-one (Cant) is an indole alkaloid found in several botanical drugs used as medicines, reported to be gastroprotective, anti-inflammatory, anti-microbial, anti-diarrheal and anti-proliferative. We aimed to explore Cant in the management of colitis using a trinitrobenzenesulfonic acid (TNBS)-induced rat model. Cant (1, 5 and 25 mg/kg) was administered by oral gavage to Wistar rats followed by induction of colitis with TNBS. Macroscopic and histopathological scores, myeloperoxidase (MPO), malondialdehyde (MDA) and reduced glutathione (GSH) were assessed in colon tissues. Pro- (TNF-α, IL-1β and IL-12p70) and anti-inflammatory (IL-10) cytokines, and vascular endothelial growth factor (VEGF) were also quantified. Mitogen-activated protein kinase 14 (MAPK14) and Toll-like receptor-8 (TLR8), as putative targets, were considered through in silico analysis. Cant (5 and 25 mg/kg) reduced macroscopic and histological colon damage scores in TNBS-treated rats. MPO and MDA were reduced by up to 61.69% and 92.45%, respectively, compared to TNBS-treated rats alone. Glutathione concentration was reduced in rats administered with TNBS alone (50.00% of sham group) but restored to 72.73% (of sham group) with Cant treatment. TNF-α, IL-1β, IL-12p70 and VEGF were reduced, and anti-inflammatory IL-10 was increased following Cant administration compared to rats administered TNBS alone. Docking ligation results for MAPK14 (p38α) and TLR8 with Cant, confirmed that these proteins are feasible putative targets. Cant has an anti-inflammatory effect in the intestine by down-regulating molecular immune mediators and decreasing oxidative stress. Therefore, Cant could have therapeutic potential for the treatment of inflammatory bowel disease and related syndromes.

Biochemical and histopathological effects of low dose vanadium in the healing of acetic acid-induced colitis in male wistar rats

OBJECTIVES

Vanadium has been reported to possess relevant therapeutic properties such as anti-diabetic and anti-tumoral. This study aimed at determining the effects of vanadium on experimentally induced colitis in rats.

METHODS

Forty-five male Wistar rats (103 ± 3.90 g, n=15) were used for this study and were divided into three groups. Group 1 (Untreated control) had nothing added to their drinking, while groups 2 and 3 received sodium metavanadate at a dose of 50 and 200 mg/L respectively in their drinking water for 10 weeks. Colitis was thereafter induced by intra colonic administration of 1.50 mL of 6% acetic acid. Animals were sacrificed on day 0 (pre-induction), three- and seven-days post induction. Blood samples were collected for haematological variables and the distal 8 cm of the colon was collected for macroscopic, histological and biochemical (malondialdehyde-MDA, superoxide dismutase-SOD, catalase-CAT, glutathione peroxidase- GPx and nitrite concentration- NO) assessment.

RESULTS

Low dose vanadium proved beneficial in ameliorating acetic acid-induced colitis by improving both histopathological and haematological changes. Gross observation showed a faster healing rate in vanadium treated groups (50 and 200 mg/L) compared with untreated control at day 3 (40 and 26.20 vs. 2.50%) and day 7 (80 and 66.70 vs. 42%) respectively. Vanadium also appears to exert its beneficial effects on acetic acid-induced colitis via up regulation of antioxidant enzymes (SOD, CAT, GPx) and NO while decreasing the over production of MDA.

CONCLUSIONS

Vanadium at small concentration functions as an essential trace element and may be able to promote healing process during ulcerative colitis.

Management of an uncommon T-Cell lymphoma revealed by an anastomotic dehiscence in Crohn's disease: A case report

•

The association of cancer and crohn’s disease is well known.

•

Immunosuppressants are associated with a carcinological risk.

•

The onset of T-cell Lymphoma in the course of crohn’s disease is a very rare finding.

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The revelation of non-hodgkin lymphoma by anastomotic dehiscence in crohn’s disease is not well documented in literature.

Introduction and importance

T-cell lymphoma degeneration in pancolic crohn’s disease is scarce. It is mostly related to long-standing inflammatory bowel disease in patients under immunosuppressants. We reviewed the clinical, endoscopic, radiological and histologic data of the patient as well as the literature dealing with T-cell lymphoma arising from pancolic crohn’s disease.

Case presentation

We describe in this paper an unusual case of a female young patient who underwent emergency surgery for per endoscopic perforation of the right colon while being under azathioprine. She had a subtotal colectomy with ileostomy and sigmoidostomy. After six months, we restored the digestive continuity through an ileorectal anastomosis. She was kept in remission on azathioprine. After one year, she presented with a pelvic abscess revealing a dehiscence of the ileorectal anastomosis leading to a surgical drainage and resection of the anastomosis associated with terminal ileostomy and closure of the rectal stump. Pathology examination revealed T cell lymphoma arising from the ileorectal anastomosis.

Discussion

Patients with long-standing IBD have an increased risk of developing colorectal cancer. The onset of a malignant lymphoma during the course of the CD is scarce. Some studies haves failed to identify crohn’s disease as a risk factor of lymphoma whereas other ones have succeeded to. Immunosuppressants are reported to have carcinogenic effect. Rarely, lymphoma degeneration can be revealed by intestinal complications such as perforation like in our case.

Conclusion

Many studies reported lymphoma degeneration of crohn’s disease after long-term immunosuppressant therapy. However, rapid T-cell lymphoma degeneration revealed by anastomotic dehiscence in crohn’s disease made our case unique and interesting.

Loss of SATB2 Expression Is a Biomarker of Inflammatory Bowel Disease-associated Colorectal Dysplasia and Adenocarcinoma

SATB2 is a sensitive immunohistochemistry marker of colorectal carcinoma and non-neoplastic colorectal epithelium that is complementary to CDX2. However, its expression is affected by molecular alterations. Inflammatory bowel disease-associated neoplasia demonstrates molecular alterations that are different from those in sporadic colorectal neoplasia. Given these differences, we examined SATB2 expression in 73 cases of inflammatory bowel disease-associated neoplasia including 37 dysplasia cases and 36 carcinomas and compared the expression patterns with 50 cases of nondysplastic colorectal mucosa in patients with active inflammatory bowel disease, 40 sporadic colonic polyps (20 conventional adenomas and 20 sessile serrated lesions/polyps), and 343 sporadic colorectal adenocarcinomas to assess SATB2 immunohistochemistry as a biomarker of inflammatory bowel disease-associated neoplasia. Loss of SATB2 expression was only identified in colorectal dysplasia arising in inflammatory bowel disease (15/37, 41%) and was not seen in nondysplastic colorectal mucosa with active inflammatory bowel disease or sporadic colonic polyps (P<0.001). Loss of SATB2 expression was identified in both endoscopically visible dysplasia (11/28, 39%) and invisible (4/9, 44%) dysplasia. Loss of SATB2 expression was identified in 67% (24/36) of inflammatory bowel disease-associated carcinomas and was significantly more frequent compared with sporadic colorectal carcinomas (47/343, 14%, P<0.001). There was no difference in positive CDX2 expression between inflammatory bowel disease-associated colorectal carcinoma and sporadic colorectal carcinoma (89% vs. 85%, P=1.0). In conclusion, loss of SATB2 expression is common in inflammatory bowel disease-associated colorectal dysplasia and adenocarcinoma and may be a helpful ancillary biomarker when evaluating for inflammatory bowel disease-associated dysplasia.

Inflammatory bowel disease (IBD) position statement of the Italian Society of Colorectal Surgery (SICCR): general principles of IBD management

The Italian Society of Colorectal Surgery (SICCR) promoted the project reported here, which consists of a Position Statement of Italian colorectal surgeons to address the surgical aspects of inflammatory bowel disease management. Members of the society were invited to express their opinions on several items proposed by the writing committee, based on evidence available in the literature. The results are presented, focusing on relevant points. The present paper is not an alternative to available guidelines; rather, it offers a snapshot of the attitudes of SICCR surgeons about the general principles of surgical treatment of inflammatory bowel disease. The committee was able to identify some points of major disagreement and suggested strategies to improve quality of available data and acceptance of guidelines.

Traditional serrated adenoma-like lesions in patients with inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) have an increased risk of colorectal carcinoma. The significance of serrated lesions resembling traditional serrated adenoma (TSA) in IBD patients is unclear. In this retrospective study, we analyzed 52 TSA-like lesions arising in 30 IBD patients and diagnosed in colectomy or endoscopic specimens. The 27 colectomy lesions presented predominantly as ill-defined areas with granular appearance, with a median size of 15 mm, located throughout the large bowel and associated with synchronous advanced colorectal lesions in 58%. Low-grade serrated dysplasia was present in 56%, high-grade serrated dysplasia in 37%, and TSA-type cytology in 7%. Increased Ki-67 immunostaining and abnormal p53 expression were identified in 96% and 48%, respectively; 74% had a KRAS mutation, and 4% had a BRAF mutation. Endoscopically resectable TSA-like lesions were all discrete polypoid lesions, smaller in size (median 9 mm), predominantly in the distal large bowel, with an adjacent precursor polyp in 24%, and associated with synchronous and metachronous advanced colorectal lesions in 6%. Most (92%) show TSA-type cytology. p53 overexpression was present in 4%, KRAS mutation in 41%, and BRAF mutation in 32%. None of the 52 TSA-like lesions demonstrated loss of MLH1 or SATB2 expression by immunohistochemistry. On follow-up, 4 patients were diagnosed with colorectal carcinoma or high-grade adenomatous IBD-associated dysplasia. None of the patients with lesions showing TSA-type cytology only developed an advanced lesion. Our findings suggest that some TSA-like lesions, essentially from colectomy, may represent a form of IBD-associated dysplasia associated with an increased risk of advanced neoplasia.

Association Between Inflammatory Bowel Disease and Colorectal Cancer Stage of Disease and Survival

BACKGROUND

Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (CRC). However, there are few data comparing outcomes between IBD and non-IBD-associated CRC.

METHODS

Retrospective cohort study of patients with CRC identified from the Veteran Affairs (VA) Central Cancer Registry from 1998 to 2012 linked to national VA administrative claims to identify patients with IBD using a previously validated algorithm. The association between IBD status and stage of disease and overall risk of death were evaluated using multivariable logistic and Cox regression, respectively.

RESULTS

Among 34,570 CRC patients, 217 had IBD. IBD patients were significantly younger for both colon and rectal cancer. IBD patients who developed rectal cancer were significantly more likely to present with locally advanced or metastatic disease (P = 0.007), but there was no difference in stage among patients with colon cancer. This difference persisted after multivariable adjustment (overall-odds ratio [OR] 1.40, 95% confidence interval [1.03-1.90]; colon-OR 1.22 [0.84-1.78]; rectum-OR 2.04 [1.22-3.40]). Total colectomy was more commonly performed among IBD patients. Overall, IBD was associated with a 52% increased risk of death (hazard ratio 1.52 [1.21-1.91]).

CONCLUSIONS

Although IBD is associated with more advanced stage at diagnosis for rectal cancer, it is associated with a worse survival primarily in patients with colon cancer. Further work is needed to better understand the reason for these observed differences between IBD and non-IBD patients and to better delineate the impact of endoscopic surveillance on CRC care and outcomes in IBD patients.

Functional Prediction of Candidate MicroRNAs for CRC Management Using in Silico Approach

Approximately 30–50% of malignant growths can be prevented by avoiding risk factors and implementing evidence-based strategies. Colorectal cancer (CRC) accounted for the second most common cancer and the third most common cause of cancer death worldwide. This cancer subtype can be reduced by early detection and patients’ management. In this study, the functional roles of the identified microRNAs were determined using an in silico pipeline. Five microRNAs identified using an in silico approach alongside their seven target genes from our previous study were used as datasets in this study. Furthermore, the secondary structure and the thermodynamic energies of the microRNAs were revealed by Mfold algorithm. The triplex binding ability of the oligonucleotide with the target promoters were analyzed by Trident. Finally, evolutionary stage-specific somatic events and co-expression analysis of the target genes in CRC were analyzed by SEECancer and GeneMANIA plugin in Cytoscape. Four of the five microRNAs have the potential to form more than one secondary structure. The ranges of the observed/expected ratio of CpG dinucleotides of these genes range from 0.60 to 1.22. Three of the candidate microRNA were capable of forming multiple triplexes along with three of the target mRNAs. Four of the total targets were involved in either early or metastatic stage-specific events while three other genes were either a product of antecedent or subsequent events of the four genes implicated in CRC. The secondary structure of the candidate microRNAs can be used to explain the different degrees of genetic regulation in CRC due to their conformational role to modulate target interaction. Furthermore, due to the regulation of important genes in the CRC pathway and the enrichment of the microRNA with triplex binding sites, they may be a useful diagnostic biomarker for the disease subtype.

Synchronous colonic adenoma and intestinal marginal zone B-cell lymphoma associated with Crohn's disease: a case report and literature review

Background

Lymphoma and dysplasia are rare complications of long-standing Crohn’s disease. We report an exceptional case of a synchronous intestinal marginal zone B-cell lymphoma (MALT lymphoma) and colonic adenoma in a Crohn’s disease patient.

Case presentation

A 50-year-old male patient presented with right lower quadrant for the last 9 months. He also had associated weight loss and diarrhea alternating with constipation. Ileo-colonoscopy revealed a pseudopolypoid appearance of the colonic and ileal mucosa with many discontinuous ulcerations with a 3 cm sessile polypoid mass at 17 cm from the anal verge. Histological examination of the polypoid lesion revealed an adenoma with high grade dysplasia, while the biopsies of colonic mucosa showed histologic features of Crohn’s disease. Abdominal computed tomography scan (CT scan) and magnetic resonance imaging (MRI) showed circumferential wall thickening of the colon and ileum, enlarged mesenteric lymph nodes and a sessile polypoid mass of the rectosigmoid junction. The patient was scheduled for an ileocoletectomy with resection of the upper rectum and ileorectostomy.

The histological examination of the resected segment showed histologic features of Crohn’s disease, a recto-sigmoid polyp with high grade.

dysplasia and extensive small lymphocytic infiltrate in both colonic and ileal wall which is strongly stained by CD20 and BCL2. The diagnosis of MALT lymphoma with adenoma on a background of Crohn’s disease was made.

The patient successfully completed 8 cycles of Rituximab+ chlorambucil chemotherapy.

Nowadays the patient is asymptomatic without evidence of lymphoproliferative recurrence 10 months after surgery.

Conclusion

We report the first case in the literature of Malt lymphoma with colonic adenoma associated with Crohn’s disease, and discuss his unique macroscopic and histological features in a patient.

Without immunosuppressive therapy.

Difference in the clinical characteristic and prognosis of colitis-associated cancer and sporadic neoplasia in ulcerative colitis patients

BACKGROUND

Although various studies have been conducted on colitis-associated cancer (CAC), few have assessed the differences in the clinical and endoscopic features, treatment, and prognosis of CAC and sporadic neoplasia (SN) in the inflamed mucosa of ulcerative colitis (UC) patients.

AIMS

To compare the characteristics of CAC and SN within the previously or currently inflamed mucosa.

METHODS

Between 1997 and 2017, we retrospectively analyzed the endoscopic chart data of 348 colonic lesions from 266 UC patients. Non-dysplastic lesions and lesions located outside the inflamed mucosa were excluded. The diagnosis of CAC or SN was confirmed by conventional histopathological and immunohistochemical evaluation of p53 and Ki67.

RESULTS

In total, 74 patients with CAC (97 lesions) and 46 with SN (58) were enrolled. The proportions of patients with a younger age of onset of UC, with chronic persistent UC, and with severe inflamed mucosa were significantly higher in the CAC group. In the SN group, no flat lesions were found, whereas 26% of the lesions in the CAC group were flat. Sixteen patients died during a median follow-up of 6.1 years (interquartile range (IQR) 1.8-11.1)in the CAC group, whereas 1 patient died during a median follow-up 3.2 years(IQR 1.4-4.6) in the SN group. Mortality from colorectal cancer was significantly higher (P = 0.015) in the CAC group (12/68; 17.6%) than in the SN group (1/44; 2.3%). The 5-year survival rate was 100% in the SN group and 97% in the CAC group for lesions located in the mucosa or submucosa.

CONCLUSION

Recognizing differences in the characteristics of CAC and SN within the inflamed mucosa is critical to avoid unnecessary total colectomy in patients with SN.

Protective mechanisms of 6-gingerol in dextran sulfate sodium-induced chronic ulcerative colitis in mice

Ulcerative colitis (UC) is a relapsing and remitting inflammatory disease of the colon, with an increasing incidence worldwide. 6-Gingerol (6G) is a bioactive constituent of Zingiber officinale, which has been reported to possess various biological activities. This study was designed to evaluate the role of 6G in chronic UC. Chronic UC was induced in mice by three cycles of 2.5% dextran sulfate sodium (DSS) in drinking water. Each cycle consisted of 7 days of 2.5% DSS followed by 14 days of normal drinking water. 6G (100 mg/kg) and a reference anti-colitis drug sulfasalazine (SZ) (100 mg/kg) were orally administered daily to the mice throughout exposure to three cycles of 2.5% DSS. Administration of 6G and SZ significantly prevented disease activity index and aberrant crypt foci formation in DSS-treated mice. Furthermore, 6G and SZ suppresses immunoexpression of tumor necrosis factor alpha, interleukin-1β, inducible nitric oxide synthase, Regulated on activation, normal T cell expressed and secreted (RANTES), and Monocyte chemoattractant protein-1 (MCP-1) in the DSS-treated mice. 6G effectively protected against colonic oxidative damage by augmenting the antioxidant status with marked decrease in lipid peroxidation levels in DSS-treated mice. Moreover, 6G significantly inhibited nuclear factor kappa B (P65), p38, cyclooxygenase-2, and β-catenin whereas it enhanced IL-10 and adenomatous polyposis coli expression in DSS-treated mice. In conclusion, 6G prevented DSS-induced chronic UC via anti-inflammatory and antioxidative mechanisms and preservation of the Wnt/β-catenin signaling pathway.

Distinct Histopathologic and Molecular Alterations in Inflammatory Bowel Disease-Associated Intestinal Adenocarcinoma: c-MYC Amplification is Common and Associated with Mucinous/Signet Ring Cell Differentiation

BACKGROUND

Chronic idiopathic inflammatory bowel disease (IBD) is a significant risk factor for the development of intestinal adenocarcinoma. The underlying molecular alterations in IBD-associated intestinal adenocarcinoma remain largely unknown.

METHODS

We compared the clinicopathologic and molecular features of 35 patients with 47 IBD-associated intestinal adenocarcinomas with a consecutive series of 451 patients with sporadic colorectal carcinoma identified at our institution and published data on sporadic colorectal carcinoma.

RESULTS

c-MYC amplification was the most frequent molecular alteration identified in 33% of IBD-associated intestinal adenocarcinoma that is a significantly higher frequency than in sporadic colorectal carcinoma (8%) (P = 0.0001). Compared to sporadic colorectal carcinoma, IBD-associated intestinal adenocarcinomas more frequently demonstrated mucinous differentiation (60% vs 25%, P < 0.001) and signet ring cell differentiation (28% vs 4%, P < 0.001). Mucinous and signet ring cell differentiation were significantly associated with the presence of c-MYC amplification (both with P < 0.05). HER2 positivity (11%), KRAS exon 2 or 3 mutation (10%), and IDH1 mutation (7%) were less commonly observed in IBD-associated intestinal adenocarcinoma. There was an association between poor survival and HER2 status with 3 of 4 patients having HER2-positive adenocarcinoma dead of disease at last clinical follow-up; however, no statistically significant survival effect was identified for any of the molecular alterations identified.

CONCLUSIONS

We demonstrate that IBD-associated intestinal adenocarcinomas have a high frequency of c-MYC amplification that is associated with mucinous and signet ring cell differentiation. Many of the identified molecular alterations have potential therapeutic relevance, including HER2 amplification, IDH1 mutation, and low frequency KRAS mutation.

B-cell lymphoma 2 is associated with advanced tumor grade and clinical stage, and reduced overall survival in young Chinese patients with colorectal carcinoma

The development of biomarkers that accurately and reliably detect colorectal cancer is a promising approach for colorectal cancer screening. Therefore, the objective of the present study was to evaluate the protein expression of α-methylacyl-CoA racemase (P504S/AMACR), tumor protein p53 (p53), B-cell lymphoma 2 (Bcl-2) and Ki-67/mindbomb E3 ubiquitin protein ligase 1 (MIB-1) in a population of Chinese patients with colorectal carcinoma. Colorectal tumors with matched normal tissue margins were collected from 148 surgical patients, and the demographic and clinical characteristics were collected. Immunohistochemical staining and western blot analysis of P504S/AMACR, p53, Bcl-2 and Ki-67/MIB-1 were conducted. Statistical analyses were used to compare protein expression in the colorectal tumors and matched normal tissue margins and to identify any associations between them and various clinicopathological parameters. Survival analyses were performed using the Kaplan-Meier method. In the present study, immunohistochemistry and western blot analysis revealed significantly higher expression of all four proteins in colorectal tumors compared with matched normal tissue margins (P<0.001). Spearman's rank correlation analysis revealed that Bcl-2 expression was negatively correlated with pathological grade and Tumor-Node-Metastasis (TNM) stage (-0.827 and -0.388, respectively; P<0.05). Bcl-2 expression was revealed to be a significant prognostic indicator of colorectal carcinoma [relative risk (95% CI), 0.703 (0.552-0.895); P<0.05]. The log-rank test revealed a significant association between low Bcl-2 expression and reduced overall survival (P=0.039), as well as a significant association between older age (>55 years) and reduced overall survival (P<0.001) in Chinese patients with colorectal carcinoma. In conclusion, low expression of Bcl-2 is significantly correlated with advanced pathological grade and TNM stage and is a prognostic indicator of reduced overall survival in young Chinese patients with colorectal carcinoma.

Are random biopsies still useful for the detection of neoplasia in patients with IBD undergoing surveillance colonoscopy with chromoendoscopy?

BACKGROUND

Colonoscopy with pan-chromoendoscopy (CE) is superior to standard colonoscopy in detecting neoplasia in patients with IBD. Performing random biopsies in unsuspicious mucosa after CE remains controversial.

METHODS

Consecutive patients with IBD who underwent surveillance colonoscopy using CE were prospectively included. The standardised procedure used CE, performed targeted biopsies or endoscopic resection on suspicious lesions and then quadrant random biopsies every 10 cm. A panel of five expert pathologists reviewed histological slides with dysplasia. Logistic regression model was used to evidence the factors associated with neoplasia in any or in random biopsies.

RESULTS

1000 colonoscopes were performed in 1000 patients (495 UC, 505 Crohn's colitis). In 82 patients, neoplasia was detected from targeted biopsies or removed lesions, and among them dysplasia was detected also by random biopsies in 7 patients. Importantly, in 12 additional patients dysplasia was only detected by random biopsies. Overall, 140 neoplastic sites were found in 94 patients, 112 (80%) from targeted biopsies or removed lesions and 28 (20%) by random biopsies. The yield of neoplasia by random biopsies only was 0.2% per-biopsy (68/31 865), 1.2% per-colonoscopy (12/1000) but 12.8% per-patient with neoplasia (12/94). Dysplasia detected by random biopsies was associated with a personal history of neoplasia, a tubular appearing colon and the presence of primary sclerosing cholangitis (PSC).

CONCLUSIONS

Despite their low yield, random biopsies should be performed in association with CE in patients with IBD with a personal history of neoplasia, concomitant PSC or a tubular colon during colonoscopy.

TRIAL REGISTRATION NUMBER

IRB 001508, Paris 7 University.

Could Mycobacterium avium subspecies paratuberculosis cause Crohn's disease, ulcerative colitis…and colorectal cancer?

Infectious agents are known causes of human cancers. Schistosoma japonicum and Schistosoma mansoni cause a percentage of colorectal cancers in countries where the respective Schistosoma species are prevalent. Colorectal cancer is a complication of ulcerative colitis and colonic Crohn’s disease, the two main forms of idiopathic inflammatory bowel disease (IIBD). Mycobacterium avium subspecies paratuberculosis (MAP), the cause of a chronic intestinal disease in domestic and wild ruminants, is one suspected cause of IIBD. MAP may therefore be involved in the pathogenesis of IIBD-associated colorectal cancer as well as colorectal cancer in individuals without IIBD (sporadic colorectal cancer) in countries where MAP infection of domestic livestock is prevalent and MAP’s presence in soil and water is extensive. MAP organisms have been identified in the intestines of patients with sporadic colorectal cancer and IIBD when high magnification, oil immersion light microscopy (×1000 total magnification rather than the usual ×400 total magnification) is used. Research has demonstrated MAP’s ability to invade intestinal goblet cells and cause acute and chronic goblet cell hyperplasia. Goblet cell hyperplasia is the little-recognized initial pathologic lesion of sporadic colorectal cancer, referred to as transitional mucosa, aberrant crypt foci, goblet cell hyperplastic polyps or transitional polyps. It is the even lesser-recognized initial pathologic feature of IIBD, referred to as hypermucinous mucosa, hyperplastic-like mucosal change, serrated epithelial changes, flat serrated changes, goblet cell rich mucosa or epithelial hyperplasia. Goblet cell hyperplasia is the precursor lesion of adenomas and dysplasia in the classical colorectal cancer pathway, of sessile serrated adenomas and serrated dysplasia in the serrated colorectal cancer pathway, and of flat and elevated dysplasia and dysplasia-associated lesions or masses in IIBD-associated intestinal cancers. MAP’s invasion of intestinal goblet cells may result in the initial pathologic lesion of IIBD and sporadic colorectal cancer. MAP’s persistence in infected intestines may result in the eventual development of both IIBD-associated and sporadic colorectal cancer.

Endoscopic Therapeutic Approach for Dysplasia in Inflammatory Bowel Disease

Long-standing intestinal inflammation in patients with inflammatory bowel disease (IBD) induces dysplastic change in the intestinal mucosa and increases the risk of subsequent colorectal cancer. The evolving endoscopic techniques and technologies, including dye spraying methods and high-definition images, have been replacing random biopsies and have been revealed as more practical and efficient for detection of dysplasia in IBD patients. In addition, they have potential usefulness in detailed characterization of lesions and in the assessment of endoscopic resectability. Most dysplastic lesions without an unclear margin, definite ulceration, non-lifting sign, and high index of malignant change with suspicion for lymph node or distant metastases can be removed endoscopically. However, endoscopic resection of dysplasia in chronic IBD patients is usually difficult because it is often complicated by submucosal fibrosis. In patients with dysplasias that demonstrate submucosa fibrosis or a large size (≥20 mm), endoscopic submucosal dissection (ESD) or ESD with snaring (simplified or hybrid ESD) is an alternative option and may avoid a colectomy. However, a standardized endoscopic therapeutic approach for dysplasia in IBD has not been established yet, and dedicated specialized endoscopists with interest in IBD are needed to fully investigate recent emerging techniques and technologies.

Stereomicroscopic features of colitis-associated tumors in mice: Evaluation of pit pattern

Patients with longstanding ulcerative colitis have an increased risk of colorectal cancer. Mouse models for colitis-associated tumors are indispensable for the development of novel strategies for prevention and intervention, as well as an improved understanding of the mechanisms underlying tumor formation. The present study examined whether stereomicroscopic observations with dye-application were able to detect and discriminate tumors in a colitis-associated tumor model in mice. Colonic tumors were induced in C57BL/6 mice by 15 cycles of treatment with dextran sulfate sodium (DSS) in drinking water. The mice were then divided into 4 groups: normal mice fed a control diet, normal mice fed an iron-supplemented diet, 0.7% DSS mice fed an iron diet and 1.5% DSS mice fed an iron diet. The entire colons were characterized with respect to both morphology and histology. The pit pattern architecture was analyzed using stereomicroscopy with dye agents (0.2% indigo carmine or 0.06% crystal violet). The tumor histology was graded as negative, indefinite or positive for dysplasia. The positive category was divided into two subcategories: low-grade dysplasia (LGD) and high-grade dysplasia (HGD). The tumor incidences and multiplicity were significantly higher in mice fed an iron diet and 1.5% DSS compared with in mice fed an iron diet and 0.7% DSS. Compared with LGD, HGD was predominantly located in the distal colon, was larger in size and had a higher incidence of elevated lesions (Is and IIa) and a lower incidence of flat lesions (IIb). In regards to the pit pattern, HGD had a high incidence of V_I pits and a low incidence of IV, III_L and II pits. In conclusion, evaluation of the pit pattern using stereomicroscopy with dye-application is useful for detecting and discriminating neoplastic changes in DSS mice and may further our understanding of the mechanisms that induce tumor formation in patients with ulcerative colitis and the characterization of pharmaceutical responses.

Downregulation of serum metabolite GTA-446 as a novel potential marker for early detection of colorectal cancer

BACKGROUND

We previously reported that GTA-446 may be a useful biomarker for early detection of colorectal cancer. In the present study, we confirmed the clinical feasibility of GTA-446 as a screening tool for colorectal cancer with a novel measurement system developed for clinical use. We also improved sensitivity by analysing GTA-446 levels according to gender.

METHODS

Serum samples were collected from 225 colorectal cancer patients and 916 healthy volunteers to measure GTA-446 levels by flow injection analysis-mass spectrometry.

RESULTS

GTA-446 levels were downregulated in colorectal cancer patients compared with the healthy volunteers, and in females compared with the males in both groups. Receiver operating characteristic curve analysis revealed an optimal cut-off of 2.72 μmol l^-1 in males and 1.87 μmol l^-1 in females, with a large area under the curve of 0.89-0.93. The sensitivity and specificity were 90.4% and 84.9% for males, 85.2% and 80.5% for females, and 83.3% and 84.8% for all subjects, respectively.

CONCLUSIONS

GTA-446 is a clinically relevant biomarker for colorectal cancer with high sensitivity when analysed by gender. Thus, GTA-446 is a promising tool for primary colorectal cancer screening to identify populations at a higher risk of colorectal cancer, with an emphasis on early detection.

Low-grade slightly elevated and polypoid colorectal adenomas display differential β-catenin-TCF/LEF activity, c-Myc, and cyclin D1 expression

AIM

To comparatively investigate the cellular and molecular characteristics of low-grade slightly elevated adenomas and polypoid adenomas.

METHODS

Colorectal tumors were collected from 24 patients with slightly elevated adenomas and 23 patients with polypoid adenomas. Five commonly mutated genes (APC, BRAF, KRAS, NRAS, and PIK3CA) were selected for mutational analysis. Paraffin-embedded tumor sections were used to calculate the apoptotic index (AI) and Ki-67 labeling index (KLI). Two pure colorectal epithelial cell lines were created by pooling the slightly elevated and polypoid tumors. Western blots, luciferase assays for β-catenin-T-cell factor protein/β-catenin-lymphoid enhancer factor (β-catenin-TCF/LEF)-driven transcriptional activity, and caspase activity assays were conducted on the two cell lines.

RESULTS

Slightly elevated lesions showed a significantly lower APC mutational frequency and a significantly higher KRAS mutational frequency (both P < 0.05). Slightly elevated lesions showed a significantly lower AI (P < 0.05). β-catenin and β-catenin-TCF/LEF-driven transcriptional activity was significantly upregulated in slightly elevated lesions (both P < 0.05). In slightly elevated lesions, c-Myc was significantly downregulated, while cyclin D1 was significantly upregulated (both P < 0.05). β-catenin-TCF/LEF-driven transcriptional activity was negatively correlated with c-Myc (ρ = -0.78). Slightly elevated lesions displayed significant Bcl-2 and Bcl-xL upregulation (both P < 0.05) along with significant decreases in caspase-9 and caspase-3 activity (both P < 0.05). c-Myc was negatively correlated with Bcl-2 and Bcl-xL (ρ = -0.74 and -0.78, respectively).

CONCLUSION

The lower apoptotic activity of low-grade slightly elevated adenomas can be partly attributed to upregulated β-catenin pathway activity and downregulated c-Myc expression.

Endoscopic morphologic features of ulcerative colitis-associated dysplasia classified according to the SCENIC consensus statement

BACKGROUND AND AIMS

Recent advances in endoscopic equipment and diagnostic techniques have made possible the detection of early dysplasia in the inflamed mucosa of ulcerative colitis (UC). The SCENIC consensus statement recommends the use of unified terminology for the morphology of dysplasia. In this study, we investigated the endoscopic features of high-grade dysplasia (HGD) in a clinical setting.

METHODS

We retrospectively identified 62 patients with UC who were diagnosed with colitis-associated cancer or HGD between 1997 and 2015. A total of 39 lesions of HGD detected by targeted biopsy sampling in 31 patients were reviewed, and the endoscopic morphology was classified according to the SCENIC guidelines.

RESULTS

In total, 0 (0%), 6 (15.4%), 19 (48.7%), 12 (30.8%), and 2 (5.1%) lesions with HGD were classified as pedunculated, sessile, superficial elevated, flat, and depressed, respectively. Nearly 80% of the lesions were located in the rectum or sigmoid colon. All flat and depressed lesions were red in color. Typically, sessile/superficial elevated lesions accompanied a flat area (Is+IIb/IIa+IIb). Ulceration was observed in 2 depressed lesions (5.1%). Although the borders were indistinct in 21 lesions (53.8%) without the use of magnifying colonoscopy, all lesions could be distinguished from the surrounding mucosa using magnifying endoscopy.

CONCLUSIONS

This is the first study to classify the morphologic features of HGD using the SCENIC guidelines in a clinical setting. Based on our findings, endoscopists should recognize that HGD is frequently associated with a flat/superficial elevated area and red discoloration and should inspect particularly carefully in the rectum and sigmoid colon. The findings of chromoendoscopy and magnifying colonoscopy may also be useful in distinguishing lesions from the surrounding mucosa.

Fucosylation Deficiency in Mice Leads to Colitis and Adenocarcinoma

BACKGROUND & AIMS

De novo synthesis of guanosine diphosphate (GDP)-fucose, a substrate for fucosylglycans, requires sequential reactions mediated by GDP-mannose 4,6-dehydratase (GMDS) and GDP-4-keto-6-deoxymannose 3,5-epimerase-4-reductase (FX or tissue specific transplantation antigen P35B [TSTA3]). GMDS deletions and mutations are found in 6%-13% of colorectal cancers; these mostly affect the ascending and transverse colon. We investigated whether a lack of fucosylation consequent to loss of GDP-fucose synthesis contributes to colon carcinogenesis.

METHODS

FX deficiency and GMDS deletion produce the same biochemical phenotype of GDP-fucose deficiency. We studied a mouse model of fucosylation deficiency (Fx-/- mice) and mice with the full-length Fx gene (controls). Mice were placed on standard chow or fucose-containing diet (equivalent to a control fucosylglycan phenotype). Colon tissues were collected and analyzed histologically or by enzyme-linked immunosorbent assays to measure cytokine levels; T cells also were collected and analyzed. Fecal samples were analyzed by 16s ribosomal RNA sequencing. Mucosal barrier function was measured by uptake of fluorescent dextran. We transplanted bone marrow cells from Fx-/- or control mice (Ly5.2) into irradiated 8-week-old Fx-/- or control mice (Ly5.1). We performed immunohistochemical analyses for expression of Notch and the hes family bHLH transcription factor (HES1) in colon tissues from mice and a panel of 60 human colorectal cancer specimens (27 left-sided, 33 right-sided).

RESULTS

Fx-/- mice developed colitis and serrated-like lesions. The intestinal pathology of Fx-/- mice was reversed by addition of fucose to the diet, which restored fucosylation via a salvage pathway. In the absence of fucosylation, dysplasia appeared and progressed to adenocarcinoma in up to 40% of mice, affecting mainly the right colon and cecum. Notch was not activated in Fx-/- mice fed standard chow, leading to decreased expression of its target Hes1. Fucosylation deficiency altered the composition of the fecal microbiota, reduced mucosal barrier function, and altered epithelial proliferation marked by Ki67. Fx-/- mice receiving control bone marrow cells had intestinal inflammation and dysplasia, and reduced expression of cytokines produced by cytotoxic T cells. Human sessile serrated adenomas and right-sided colorectal tumors with epigenetic loss of MutL homolog 1 (MLH1) had lost or had lower levels of HES1 than other colorectal tumor types or nontumor tissues.

CONCLUSIONS

In mice, fucosylation deficiency leads to colitis and adenocarcinoma, loss of Notch activation, and down-regulation of Hes1. HES1 loss correlates with the development of human right-sided colorectal tumors with epigenetic loss of MLH1. These findings indicate that carcinogenesis in a subset of colon cancer is consequent to a molecular mechanism driven by fucosylation deficiency and/or HES1-loss.

The Significance of Sessile Serrated Polyps in Inflammatory Bowel Disease

BACKGROUND

The significance of serrated lesions in inflammatory bowel disease (IBD) remains unclear. We aim to characterize synchronous and metachronous lesions in IBD patients with an index serrated polyp and compare them to sporadic subjects with SSP.

METHODS

Serrated lesions in patients with IBD were identified from a pathology database and, after review, were reclassified as hyperplastic (HP), sessile serrated (SSPs), or serrated polyps unclassifiable (SPU).

RESULTS

One hundred thirty-four IBD patients were found to have 147 serrated polyps at index colonoscopy. SSPs were more likely to be located in the right colon: SSP (76.0%), SPU (41.7%) and HP (27.8%); P = 0.002. Synchronous multifocal visible dysplasia occurred more frequently in the SSP or SPU groups (44.5% and 66%) compared to the HP group (12%); P = 0.031. Among 13 IBD patients with index SSP followed over a median of 6 years, 61.5% developed metachronous visible dysplasia or additional SSPs. Larger index SSP size was associated with higher risk of developing subsequent visible dysplasia with a 10% increase for every 1 mm increase in size (HR = 1.1; P = 0.028), but was not associated with developing subsequent SSP (P = 0.50). The risk of subsequent SSP or visible dysplasia was no different between the IBD and non-IBD groups, but there was a trend suggesting SSP may be a marker of increased early risk of metachronous visible dysplasia in IBD patients.

CONCLUSIONS

IBD patients with an index SSP and SPU have a heightened risk of synchronous multifocal visible dysplasia. Additionally, IBD patients with SSP may be at risk of early metachronous visible dysplasia.

Alpinetin attenuates inflammatory responses by suppressing TLR4 and NLRP3 signaling pathways in DSS-induced acute colitis

Alpinetin, a composition of Alpinia katsumadai Hayata, has been reported to have a number of biological properties, such as antibacterial, antitumor and other important therapeutic activities. However, the effect of alpinetin on inflammatory bowel disease (IBD) has not yet been reported. The purpose of this study was to investigate the anti-inflammatory effect and mechanism of alpinetin on dextran sulfate sodium (DSS)-induced colitis in mice. In vivo, DSS-induced mice colitis model was established by giving mice drinking water containing 5% (w/v) DSS for 7 days. Alpinetin (25, 50 and 100 mg/kg) were administered once a day by intraperitoneal injection 3 days before DSS treatment. In vitro, phorbol myristate acetate (PMA)-differentiated monocytic THP-1 macrophages were treated with alpinetin and stimulated by lipopolysaccharide (LPS). The results showed that alpinetin significantly attenuated diarrhea, colonic shortening, histological injury, myeloperoxidase (MPO) activity and the expressions of tumor necrosis factor (TNF-α) and interleukin (IL-1β) production in mice. In vitro, alpinetin markedly inhibited LPS-induced TNF-α and IL-1β production, as well as Toll-like receptor 4 (TLR4) mediated nuclear transcription factor-kappaB (NF-κB) and NOD-like receptor protein 3 (NLRP3) inflammasome activation. In conclusion, this study demonstrated that alpinetin had protective effects on DSS-induced colitis and may be a promising therapeutic reagent for colitis treatment.

Immunohistochemical expression of proinflammatory enzyme COX-2 and p53 in ulcerative colitis and its associated dysplasia and colorectal carcinoma

Background/aim

Ulcerative colitis (UC) patients are at increased risk for colorectal carcinoma (CRC). It is suggested that cyclooxygenase-2 (COX-2) plays a role in sporadic CRC. The p53 gene is a tumor-suppressor gene and the most frequent site of genetic alteration found in human cancer. The aim of this study was to analyze the immunoexpression of proinflammatory enzyme COX-2 and p53 in UC, UC-associated dysplasia, and CRC, in comparison with each other and with different clinical and histopathological parameters, to clarify if they have a possible role in the pathogenesis of CRC in UC patients.

Materials and methods

In this cross-sectional study, 98 patients were divided into three groups: 39 patients with UC without dysplasia, 32 patients with UC with dysplasia, and 27 patients with colorectal cancer on top of UC, in addition to 10 healthy controls. All patients underwent colonoscopy, and multiple biopsies were taken for histopathological and COX-2 and p53 immunohistochemical studies.

Results

There was significant difference in the expression of COX-2 and p53 in UC-related dysplasia either without or with CRC, compared with their expression in the UC group without dysplasia.

Conclusion

Adding immunohistochemical analysis of COX-2 enzyme and p53 gene to routine histological assessment may improve the accuracy of early detection of dysplasia and colorectal cancer. COX-2 and p53 can be promising chemotherapeutic/chemopreventive targets in UC patients.

Colorectal Cancer in Patients With Inflammatory Bowel Disease: The Need for a Real Surveillance Program

The association between inflammatory bowel disease (IBD) and colorectal cancer (CRC) has been widely shown. This association is responsible for 10% to 15% of deaths in patients with IBD, even if according to some studies, the risk of developing CRC seems to be decreased. An adequate surveillance of patients identified as at-risk patients, might improve the management of IBD-CRC risk. In this article we review the literature data related to IBD-CRC, analyze potential risk factors such as severity of inflammation, duration, and extent of IBD, age at diagnosis, sex, family history of sporadic CRC, and coexistent primary sclerosing cholangitis, and update epidemiology on the basis of new studies. Confirmed risk factors for IBD-CRC are severity, extent, and duration of colitis, the presence of coexistent primary sclerosing cholangitis, and a family history of CRC. Current evidence-based guidelines recommend surveillance colonoscopy for patients with colitis 8 to 10 years after diagnosis, further surveillance is decided on the basis of patient risk factors. The classic white light endoscopy, with random biopsies, is now considered unsatisfactory. The evolution of technology has led to the development of new techniques that promise to increase the effectiveness of the monitoring programs. Chromoendoscopy has already proved highly effective and several guidelines suggest its use with a target biopsy. Confocal endomicroscopy and autofluorescence imaging are currently being tested and for this reason they have not yet been considered as useful in surveillance programs.

Molecular Alterations of Colorectal Cancer with Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is an important etiologic factor in the development of colorectal cancer (CRC). The risk of CRC begins to increase 8 or 10 years after the diagnosis of IBD. This type of cancer is called colitis-associated CRC (CA-CRC). The molecular pathogenesis of inflammatory epithelium might play a critical role in the development of CA-CRC. Genetic alterations detected in CA-CRC such as genetic mutations, microsatellite instability, and DNA hypermethylation are also recognized in sporadic CRC; however, there are differences in the timing and frequency of molecular events between CA-CRC and sporadic CRC. Interaction between gene-environmental factors, including inflammation, lifestyle, psychological stress, and prior appendectomy, might be associated with the etiopathology of IBD. The mucosal inflammatory mediators, such as oxidant stress, free radicals, and chemokines, may cause the genetic alterations. Understanding the molecular mechanisms of CA-CRC might be important to develop clinical efficacies for patients with IBD. This review discusses the molecular characteristics of CA-CRC, especially ulcerative colitis-associated CRC, including clinical features, signaling pathways, and interactions between genetic alterations and environment involved in inflammatory carcinogenesis.

Radiation therapy in patients with inflammatory bowel disease and colorectal cancer: risks and benefits

PURPOSE

The effects of radiotherapy are debated in inflammatory bowel disease (IBD). We examined IBD patients with colorectal cancer (CRC) and compared those who underwent external beam radiation therapy (EBRT) to those who did not. We then compared those same patients treated with EBRT to similarly treated non-IBD patients to ascertain differences in toxicity and perioperative outcomes.

METHODS

Fifty-seven IBD patients with CRC received EBRT, of which 23 had perioperative follow-up and 15 had complete records. The 23 patients were compared to 229 IBD patients with CRC who did not receive EBRT. The 15 patients were matched, 1:2, to similarly treated non-IBD patients with CRC based on age (±5 years), treatment year (±1 year), BMI (±10 kg/m2), and clinical stage.

RESULTS

There was significantly more postoperative bleeding (5.3 % vs. 0 %, p < 0.01), wound dehiscence (3.5 % vs. 0 %, p < 0.01), and perineal infection (8.8 % vs. 1.3 %, p < 0.01) in IBD patients with EBRT compared to those without EBRT. IBD patients were significantly more likely to have grade 3 or higher lower GI toxicity (40 % vs. 7 %, p = 0.02) and wound dehiscence (36 % vs. 7 %, p = 0.02) than non-IBD patients, however without significant difference in bleeding, infection, ileus, or survival.

CONCLUSION

IBD patients with CRC who received EBRT were more likely than similar patients without EBRT to experience perioperative complications. These patients also experienced more lower GI toxicity than similarly treated non-IBD patients with CRC. The expected decrease in survival in IBD-associated CRC was not observed. Thus, EBRT may contribute to a survival benefit in this group.

Insulin-like growth factor-1 endues monocytes with immune suppressive ability to inhibit inflammation in the intestine

The pathogenesis of some chronic inflammation such as inflammatory bowel disease is unclear. Insulin-like growth factor-1 (IGF1) has active immune regulatory capability. This study aims to investigate into the mechanism by which IGF1 modulates the monocyte (Mo) properties to inhibit immune inflammation in the intestine. In this study, the production of IGF1 by intestinal epithelial cells was evaluated by real time RT-PCR and Western blotting. Mos were analyzed by flow cytometry. A mouse colitis model was created with trinitrobenzene sulfonic acid. The results showed that mouse IECs produced IGF1, which could be up regulated by exposure to CpG-ODN (CpG-oligodeoxynueleotides) in the culture. Culture the CpG-ODN-primed IEC cells and Mos or exposure of Mos to IGF1 in the culture induced the Mos to express IL-10. The IGF1-primed Mos showed the immune suppressive effect on inhibiting the immune inflammation in the mouse colon. In conclusion, the IGF1-primed Mos are capable of suppressing immune inflammation in the intestine.

Recent advancement in understanding colitis-associated tumorigenesis

Chronic inflammation predisposes patients with inflammatory bowel disease to the risk of developing colitis-associated cancer (CAC). Growing evidence strongly suggests that CAC development is multifactorial and is attributed to concurrent, dynamic dysregulations in host immunity, enteric microbiota, and epithelial restitution during the course of chronic inflammation. This article discusses the recent advances in understanding the different forms of CAC that may develop in patients with inflammatory bowel disease and animal models, as well as molecular alterations and other processes that orchestrate the development of CAC.

Arctigenin but not arctiin acts as the major effective constituent of Arctium lappa L. fruit for attenuating colonic inflammatory response induced by dextran sulfate sodium in mice

The crude powder of the fruit of Arctium lappa L. (ALF) has previously been reported to attenuate experimental colitis in mice. But, its main effective ingredient and underlying mechanisms remain to be identified. In this study, ALF was extracted with ethanol, and then successively fractionated into petroleum ether, ethyl acetate, n-butanol and water fraction. Experimental colitis was induced by dextran sulfate sodium (DSS) in mice. Among the four fractions of ALF, the ethyl acetate fraction showed the most significant inhibition of DSS-induced colitis in mice. The comparative studies of arctigenin and arctiin (the two main ingredients of ethyl acetate fraction) indicated that arctigenin rather than arctiin could reduce the loss of body weight, disease activity index and histological damage in the colon. Arctigenin markedly recovered the loss of intestinal epithelial cells (E-cadherin-positive cells) and decreased the infiltration of neutrophils (MPO-positive cells) and macrophages (CD68-positive cells). Arctigenin could down-regulate the expressions of TNF-α, IL-6, MIP-2, MCP-1, MAdCAM-1, ICAM-1 and VCAM-1 at both protein and mRNA levels in colonic tissues. Also, it markedly decreased the MDA level, but increased SOD activity and the GSH level. Of note, the efficacy of arctigenin was comparable or even superior to that of the positive control mesalazine. Moreover, it significantly suppressed the phosphorylation of MAPKs and the activation of NF-κB, including phosphorylation of IκBα and p65, p65 translocation and DNA binding activity. In conclusion, arctigenin but not arctiin is the main active ingredient of ALF for attenuating colitis via down-regulating the activation of MAPK and NF-κB pathways.

Potential dual immunomodulatory role of VEGF in ulcerative colitis and colorectal carcinoma

OBJECTIVE

Progression from ulcerative colitis (UC) toward colorectal carcinoma (CRC) is multistep process that includes gene alterations of tumor suppressor genes, such as p53 and p16. The aim of this study was to investigate the expression patterns of p16, p53 and VEGF in affected tissue and serum levels of cytokines TNF-α, IFN-γ, IL-4, IL-6, IL-10 and IL-17 in patients with UC and CRC, respectively. MATHERIALS AND METHODS. Serum levels of cytokine in patients with UC (n=24) and CRC (n=75) and in a healthy group (n=37) were analyzed by ELISA. Endoscopic biopsies specimens of UC and CRC were studied by immunohistochemical staining for p16, p53 and VEGF.

RESULTS

Patients with UC with presence of extraintestinal manifestations, complications, and positive staining of p16, p53 and VEGF respectively had higher serum levels of pro-inflammatory cytokines. Higher percentage of CRC patients had positive staining of p16, p53 and VEGF. CRC patients with positive staining of VEGF had decreased systemic values of pro-inflammatory IFN-γ and increased values of immunosuppressive IL-10.

CONCLUSIONS

Relatively low IL-10 in patients with severe UC is insufficient to compensate IL-6 secretion and subsequently enhanced type 1/17 immune response. In UC patients, p16 and p53 induce enhanced VEGF expression and subsequent production of pro-inflammatory TNF-α and IL-6. In CRC patients VEGF seems to have immunosuppressive role. It appears that tumor suppressor gene-VEGF axis have dual role on immune response in inflammation of UC and tumor growth and progression of CRC.