Colorectal Cancer in Inflammatory Bowel Diseases: A Population-Based Study in Utah

Therapeutic Potential for Sphingolipids in Inflammatory Bowel Disease and Colorectal Cancer

Inflammatory bowel disease (IBD), characterized by chronic inflammation in the intestinal tract, increases the risk for the development of colorectal cancer (CRC). Sphingolipids, which have been implicated in IBD and CRC, are a class of bioactive lipids that regulate cell signaling, differentiation, apoptosis, inflammation, and survival. The balance between ceramide (Cer), the central sphingolipid involved in apoptosis and differentiation, and sphingosine-1-phosphate (S1P), a potent signaling molecule involved in proliferation and inflammation, is vital for the maintenance of normal cellular function. Altered sphingolipid metabolism has been implicated in IBD and CRC, with many studies highlighting the importance of S1P in inflammatory signaling and pro-survival pathways. A myriad of sphingolipid analogues, inhibitors, and modulators have been developed to target the sphingolipid metabolic pathway. In this review, the efficacy and therapeutic potential for modulation of sphingolipid metabolism in IBD and CRC will be discussed.

Rectal Cancer and Radiation in Colitis

Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer. When IBD patients develop a rectal cancer, this should be treated with the same oncological principles and guidelines as the general population. Rectal cancer treatment includes surgery, chemotherapy, and radiation therapy (RT). Many IBD patients will require a total proctocolectomy with an ileal-pouch anal anastomosis (IPAA) and others, restoration of intestinal continuity may not be feasible or advisable. The literature is scarce regarding outcomes of IPAA after RT. In the present review, we will summarize the evidence regarding RT toxicity in IBD patients and review surgical strategies and outcomes of IPAA after RT.

Update and latest advances in mechanisms and management of colitis-associated colorectal cancer

Colitis-associated colorectal cancer (CAC) is defined as a specific cluster of colorectal cancers that develop as a result of prolonged colitis in patients with inflammatory bowel disease (IBD). Patients with IBD, including ulcerative colitis and Crohn's disease, are known to have an increased risk of developing CAC. Although the incidence of CAC has significantly decreased over the past few decades, individuals with CAC have increased mortality compared to individuals with sporadic colorectal cancer, and the incidence of CAC increases with duration. Chronic inflammation is generally recognized as a major contributor to the pathogenesis of CAC. CAC has been shown to progress from colitis to dysplasia and finally to carcinoma. Accumulating evidence suggests that multiple immune-mediated pathways, DNA damage pathways, and pathogens are involved in the pathogenesis of CAC. Over the past decade, there has been an increasing effort to develop clinical approaches that could help improve outcomes for CAC patients. Colonoscopic surveillance plays an important role in reducing the risk of advanced and interval cancers. It is generally recommended that CAC patients undergo endoscopic removal or colectomy. This review summarizes the current understanding of CAC, particularly its epidemiology, mechanisms, and management. It focuses on the mechanisms that contribute to the development of CAC, covering advances in genomics, immunology, and the microbiome; presents evidence for management strategies, including endoscopy and colectomy; and discusses new strategies to interfere with the process and development of CAC. These scientific findings will pave the way for the management of CAC in the near future.

Optimizing individualized management of patients with ulcerative colitis: Identification of risk factors predicting ulcerative colitis-associated neoplasia

The risk of developing colorectal neoplasia in patients with ulcerative colitis (UC) is increased. The purpose of this study is to analyze the risk factors of UC-associated neoplasia (UCAN) in UC patients and establish a clinical prediction model. 828 UC patients were included in this retrospective study. 602 patients were in discovery cohort and 226 patients were in validation cohort (internal validation cohort/external validation cohort: 120/106). Clinical and endoscopic data were collected. The discovery cohort was divided into UC group and UCAN group for univariate and multivariate binary logistic analyses. The UCAN clinical prediction model was established and verified. In the univariate analysis, 7 risk factors were related to UCAN. Multivariate logistic regression analysis showed that age at diagnosis of UC (OR: 1.018, 95% CI: 1.003-1.033), Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score (OR: 1.823, 95% CI: 1.562-2.128), and size of polyps (size1: OR: 6.297, 95% CI: 3.669-10.809; size2: OR: 12.014, 95% CI: 6.327-22.814) were independent risk factors of UCAN. A mathematical equation was established. The area under the ROC curve (AUC) of this model was calculated to be 0.845 (95%CI: 0.809-0.881). The sensitivity was 0.884 and the specificity was 0.688. The AUC of internal validation cohort was 0.901 (95%CI: 0.815, 0.988), sensitivity was 75.0% and specificity was 92.6%. The AUC of external validation cohort was 0.842 (95%CI: 0.709, 0.976), sensitivity was 62.5% and specificity was 93.9%. This prediction model is simple, practical, and effective for predicting the risk of UCAN, which is beneficial to the individualized management of patients with UC.

Determination of short-chain fatty acids as putative biomarkers of cancer diseases by modern analytical strategies and tools: a review

Short-chain fatty acids (SCFAs) are the main metabolites produced by bacterial fermentation of non-digestible carbohydrates in the gastrointestinal tract. They can be seen as the major flow of carbon from the diet, through the microbiome to the host. SCFAs have been reported as important molecules responsible for the regulation of intestinal homeostasis. Moreover, these molecules have a significant impact on the immune system and are able to affect inflammation, cardiovascular diseases, diabetes type II, or oncological diseases. For this purpose, SCFAs could be used as putative biomarkers of various diseases, including cancer. A potential diagnostic value may be offered by analyzing SCFAs with the use of advanced analytical approaches such as gas chromatography (GC), liquid chromatography (LC), or capillary electrophoresis (CE) coupled with mass spectrometry (MS). The presented review summarizes the importance of analyzing SCFAs from clinical and analytical perspective. Current advances in the analysis of SCFAs focused on sample pretreatment, separation strategy, and detection methods are highlighted. Additionally, it also shows potential areas for the development of future diagnostic tools in oncology and other varieties of diseases based on targeted metabolite profiling.

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.

Screening of serum oxysterol biomarkers for colon cancer by liquid chromatography-tandem mass spectrometry

结肠癌(CC)是全球常见恶性肿瘤之一,发病率呈逐年上升趋势,目前没有有效的标志物用于疾病早期诊断和干预跟踪。胆固醇及其氧化衍生物氧固醇在众多恶性肿瘤发生发展中发挥关键作用。该研究采用液相色谱-串联质谱(LC-MS/MS)技术,对CC临床血清样本中胆固醇及相关10种氧固醇代谢物进行了定性定量分析,并采用偏最小二乘判别分析(PLS-DA)和正交偏最小二乘判别分析(OPLS-DA)进行多元统计分析,发现上述目标代谢物能够较好地区分CC组与健康对照组。为防止数据过拟合,该研究在PLS-DA模型各代谢物变量投影重要性(VIP)基础上,结合最优组分数及K-均值聚类结果,筛选得到3种代谢标志物。通过受试者操作特征曲线(ROC)的曲线下面积(AUC)分析,发现筛选得到的3种潜在标志物联合预测CC达到0.998,说明模型性能优良。GO(基因本体论)富集分析显示3种潜在标志物主要分布在内质网和包被囊泡上,参与胆固醇代谢、运输、低密度脂蛋白重塑等生物进程,发挥胆固醇运输活性和低密度脂蛋白颗粒受体结合的分子功能。KEGG(京都基因与基因组百科全书)通路分析显示3种潜在标志物富集于类固醇生物合成、PPAR(过氧化物酶体增殖物激活受体)信号通路及ABC(ATP结合盒)转运等通路上。该研究为寻找CC标志物及进一步阐明胆固醇及氧固醇在CC发病过程中的作用奠定了一定的基础。

Colitis-Associated Colorectal Cancer in Patients with Inflammatory Bowel Diseases in a Tertiary Referral Center: A Propensity Score Matching Analysis

Background: Inflammatory bowel disease (IBD) is a risk factor in developing colitis-associated colorectal cancer (CA-CRC). CA-CRC causes the death of about 15% IBD patients and the risk is 1.5–2.4 fold higher among IBD sufferers than in the general population. The dysplasia CA-CRC develops in a different mechanism in comparison to sporadic colorectal cancer (CRC). This study aimed at evaluating the surgical treatment and its outcomes as well as 5-year survival rates in the CA-CRC and sporadic CRC patients. Materials and methods: This single-center, retrospective, propensity score-matched case-control study was conducted with 2204 patients operated on due to primary CRC, who were hospitalized from 2003 to 2019. The CA-CRC group consisted of 49 patients with CRC in the course of IBD. The sporadic CRC group was selected with the propensity score matching technique and comprised 98 patients with sporadic CRC who did not have clinical or histopathological features characteristic for IBD. Results: CA-CRC is characterized by a more aggressive clinical course. Surgical treatment of CA-CRC involves more palliative operations and is related with a higher risk of perioperative and postoperative complications. Further studies of CA-CRC risk factor stratification and the development of molecular markers hold promise in reducing CRC in IBD patients in the future were warranted.

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.

Heterogeneity of Colorectal Cancer Progression: Molecular Gas and Brakes

The review begins with molecular genetics, which hit the field unveiling the involvement of oncogenes and tumor suppressor genes in the pathogenesis of colorectal cancer (CRC) and uncovering genetic predispositions. Then the notion of molecular phenotypes with different clinical behaviors was introduced and translated in the clinical arena, paving the way to next-generation sequencing that captured previously unrecognized heterogeneity. Among other molecular regulators of CRC progression, the extent of host immune response within the tumor micro-environment has a critical position. Translational sciences deeply investigated the field, accelerating the pace toward clinical transition, due to its strong association with outcomes. While the perturbation of gut homeostasis occurring in inflammatory bowel diseases can fuel carcinogenesis, micronutrients like vitamin D and calcium can act as brakes, and we discuss underlying molecular mechanisms. Among the components of gut microbiota, Fusobacterium nucleatum is over-represented in CRC, and may worsen patient outcome. However, any translational knowledge tracing the multifaceted evolution of CRC should be interpreted according to the prognostic and predictive frame of the TNM-staging system in a perspective of clinical actionability. Eventually, we examine challenges and promises of pharmacological interventions aimed to restrain disease progression at different disease stages.

Incidence and risk factors for preneoplastic and neoplastic lesions of the colon and rectum in patients under 50 referred for colonoscopy

Colorectal cancer (CRC) diagnosed before the age of 50, known as early-onset CRC (eoCRC), is considered uncommon. We aimed at analysing the incidence of preneoplastic and neoplastic lesions of the colon and rectum in patients under 50 years old and to identify possible predictors Methods: We retrospectively collected data from 1778 patients under 50 years old (mean age 39.9±7.8) referred for colonoscopy between 2015-2018. Cumulative incidence of adenomas and eoCRC was assessed. Multivariable regression models were fitted Results: The cumulative incidence for adenomas was 11.0% (95% CI 9-12), while it was 1.5% (95% CI 1-2) for eoCRC (metastatic disease in 13/27 patients). Age as a continuous variable was associated with the presence of adenomas (incidence rate ratio 1.06; 95% CI 1.03-1.09; p<0.001). EoCRC arose in most cases in the rectum (13/27, 48.1%). Age ≥40 was the main risk factor (OR 2.25; 95% CI 1.35-3.73; p=0.002) for both adenomas (160/196 patients, 81.6%) and eoCRC (20/27 patients, 74.1%), while smoking seemed to have no role (p=0.772). The presence of alarm symptoms was statistically significant at bivariable analysis for eoCRC only (OR 3.70; 95% CI 1.49-9.22; p=0.005), as well as having multiple gastrointestinal symptoms (OR 19.85; 95% CI 2.64-149.42; p=0.004). Only 3/27 (11.1%) patients with eoCRC had a family history for CRC Conclusions: A high cumulative incidence rate of both adenomas and eoCRC was found, this latter occurring more common in patients aged 40-49, without apparent risk factors. The presence of alarm symptoms or multiple gastrointestinal symptoms led to a late diagnosis.

From inflammation to colitis-associated colorectal cancer in inflammatory bowel disease: Pathogenesis and impact of current therapies

The risk of colorectal cancer (CRC) is higher in patients with inflammatory bowel disease (IBD). Population-based data from patients with ulcerative colitis (UC) estimate that the risk of CRC is approximately 2- to 3-fold that of the general population; patients with Crohn's disease appear to have a similar increased risk. However, the true extent of colitis-associated cancer (CAC) in undertreated IBD is unclear. Data suggest that the size (i.e., severity and extent) and persistence of the inflammatory process is largely responsible for the development of CRC in IBD. As patients with IBD and CRC have a worse prognosis than those without a history of IBD, the impact of current therapies for IBD on CAC is of importance. Chronic inflammation of the gut has been shown to increase the risk of developing CAC in both UC and CD. Therefore, control of inflammation is pivotal to the prevention of CAC. This review presents an overview of the current knowledge of CAC in IBD patients, focusing on the role of inflammation in the pathogenesis of CAC and the potential for IBD drugs to interfere with the process of carcinogenesis by reducing the inflammatory process or by modulating pathways directly involved in carcinogenesis.

Effects of 5-aminosalicylates or thiopurines on the progression of low-grade dysplasia in patients with inflammatory bowel disease: a systematic review and meta-analysis

PURPOSE

Although 5-aminosalicylates and thiopurines may have an antineoplastic effect on colorectal neoplasia in patients with inflammatory bowel disease (IBD), their impact on the progression of low-grade dysplasia (LGD) in IBD is uncertain. Therefore, we performed a systematic review and meta-analysis to evaluate whether 5-aminosalicylates or thiopurines can protect against the progression of LGD in patients with IBD.

METHODS

Systematic searches of PubMed, EMBASE, Cochrane Library databases, and major conference proceedings were conducted to identify all eligible studies through March 2020. Data were pooled using a random effects model. Study quality was assessed using the Newcastle-Ottawa Scale.

RESULTS

Five studies comprising 776 IBD patients with LGD were included. Overall, 5-aminosalicylates (Hazard ratio (HR) = 0.91, 95% confidence interval (CI) 0.55-1.51) and thiopurines (HR = 0.64, 95% CI 0.23-1.79) did not significantly reduce the risk of advanced colorectal neoplasia (high-grade dysplasia/cancer) in IBD patients with LGD. Moreover, the effects of 5-aminosalicylates or thiopurines on risk of advanced colorectal neoplasia in IBD patients with LGD were not significant by different primary sclerosing cholangitis status, study quality, sample size, and IBD type.

CONCLUSIONS

In this study, we did not find a significant protective effect of 5-aminosalicylates or thiopurines on the progression of LGD in patients with IBD.

Sex matters: impact on pathogenesis, presentation and treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD), as do most chronic inflammatory disorders, displays unique features and confers different risk factors in male and female patients. Importantly, sex-based differences in IBD exist for epidemiological incidence and prevalence among different age groups, with men and women developing distinct clinical symptoms and disparity in severity of disease. In addition, the presentation of comorbidities in IBD displays strong sex differences. Notably, particular issues exclusive to women's health, including pregnancy and childbirth, require specific considerations in female patients with IBD of childbearing age that can have a substantial influence on clinical outcomes. This Review summarizes the latest findings regarding sex-based differences in the epidemiology, clinical course, comorbidities and response to current therapies in patients with IBD. Importantly, the latest basic science discoveries in this area of investigation are evaluated to provide insight into potential mechanisms underlying the influence of sex on disease pathogenesis, as well as to design more personalized and efficacious care, in patients with IBD.

Blood Cell DNA Methylation of Aging-Related Ubiquitination Gene DZIP3 Can Predict the Onset of Early Stage Colorectal Cancer

There is a body of evidence that the aging immune system is linked to cancer. In this study, with aging- and immune-related DNA methylation data, we investigated the DNA methylation regulation changes in promoters with other regions of genes during aging and their association with the immune-cell proportion in the circulating whole blood of individuals. The analyses for aging- and CD4+ T cell proportion-derived differential genes showed that ubiquitination plays an important role in the aging immune system and tumorigenesis. Therefore, starting from a set of pre-annotated ubiquitination genes, we found that among the differentially ubiquitinated genes, DZIP3, an E3 ubiquitin ligase with no reports on its function in immune cells and tumorigenesis, was significantly associated with both aging (P-value = 3.86e-06) and CD4+ T cell proportion (P-value = 1.97e-05) in circulating blood. By collecting a cohort of 100 colon cancer patients and 50 healthy individuals, we validated that the 1st exon DNA methylation of DZIP3 could predict the onset of early stage (AUC = 0.833, OR = 8.82) and all pTNM stages of colorectal cancer (AUC = 0.782, OR = 5.70). Thus, the epigenetically regulated ubiquitination machine plays an important role in immune aging and tumorigenesis.

Does IBD Portend Worse Outcomes in Patients with Rectal Cancer? A Case-Matched Analysis

BACKGROUND

Patients with IBD are at increased risk for developing colorectal cancer. However, overall survival and disease-free survival for rectal cancer alone in patients with IBD has not been reported.

OBJECTIVE

This study aimed to determine overall survival and disease-free survival for patients with rectal cancer in IBD versus non-IBD cohorts.

DESIGN

This is a retrospective cohort study.

SETTING

This study was conducted at an IBD referral center.

PATIENTS

All consecutive adult patients with IBD diagnosed with rectal cancer and at least 1 year of postsurgery follow-up were included and matched in a 1:2 fashion (age, sex, preoperative stage) with patients with rectal cancer who did not have IBD.

MAIN OUTCOMES MEASURES

Five-year overall survival and disease-free survival, 30-day postoperative complication, readmission, reoperation, and mortality rates were measured.

METHODS

Survival rates were calculated using Kaplan-Meier estimates. The association of risk factors and long-term outcomes was assessed using Cox proportion hazard models.

RESULTS

A total of 107 study patients with IBD who had rectal cancer were matched to 215 control patients; preoperative stages were as follows: 31% with stage I, 19% with stage II, 40% with stage III, and 10% with stage IV. Differences were observed (IBD vs non-IBD) in neoadjuvant chemotherapy (33.6% vs 52.6%, p = 0.001) and preoperative radiotherapy (35.5% vs 53.5%, p = 0.003). Postoperative complication rates were similar. On surgical pathology, patients with IBD had more lymphovascular invasion (12.9% vs 5.6%, p = 0.04) and positive circumferential resection margins (5.4% vs 0.9%, p = 0.03). On multivariable analysis, the diagnosis of IBD did not significantly impact long-term mortality (HR, 0.91; 95% CI, 0.53-1.57; p = 0.73) or disease-free survival (HR, 1.36; 95% CI, 0.84-2.21; p = 0.22).

LIMITATIONS

This study was limited by its retrospective design and the use of single-center data.

CONCLUSIONS

Patients have rectal cancer with IBD and without IBD have similar long-term and disease-free survival, despite lower rates of neoadjuvant treatment and higher margin positivity in patients with IBD. See Video Abstract at http://links.lww.com/DCR/B271. ¿LA ENFERMEDAD INFLAMATORIA INTESTINAL ACARREA PEORES RESULTADOS EN PACIENTES CON CÁNCER RECTAL? UN ANÁLISIS DE CASOS-COINCIDENTES: Los pacientes con enfermedad inflamatoria intestinal (EII) tienen un mayor riesgo de desarrollar cáncer colorrectal. Sin embargo, no se ha informado la supervivencia general y la supervivencia libre de enfermedad para el cáncer rectal solo en pacientes con EII.Determinar la supervivencia general y la supervivencia libre de enfermedad para pacientes con cáncer rectal en cohortes con EII versus sin EII.Estudio de cohorte retrospectivo.Centro de referencia para enfermedad inflamatoria intestinal.todos los pacientes adultos con EII diagnosticados con cáncer rectal, consecutives, y al menos un año de seguimiento postoperatorio se incluyeron y se emparejaron de manera 1: 2 (edad, sexo, etapa preoperatoria) con pacientes con cáncer rectal sin EII.Se midieron la supervivencia general a cinco años y la supervivencia libre de enfermedad, complicaciones postoperatorias a los 30 días, reingreso, reoperación y tasas de mortalidad.Las tasas de supervivencia se calcularon utilizando estimaciones de Kaplan-Meier. La asociación de factores de riesgo y resultados a largo plazo se evaluó mediante modelos de riesgo de proporción de Cox.Un total de 107 pacientes con EII y cáncer rectal se compararon con 215 pacientes de control; las etapas preoperatorias fueron las siguientes: 31% de Etapa I, 19% de Etapa II, 40% de Etapa III y 10% de Etapa IV. Se observaron diferencias (EII versus no EII) en quimioterapia neoadyuvante (33.6% frente a 52.6%, p = 0.001) y radioterapia preoperatoria (35.5% frente a 53.5%, p = 0.003). Las tasas de complicaciones postoperatorias fueron similares. En la patología quirúrgica, los pacientes con EII tuvieron más invasión linfovascular (12.9% frente a 5.6%, p = 0.04) y márgenes de resección circunferencial positivos (5.4% frente a 0.9%, p = 0.03). En el análisis multivariable, el diagnóstico de EII no tuvo un impacto significativo en la mortalidad a largo plazo (HR 0.91; IC del 95%: 0.53-1.57, p = 0.73) o la supervivencia libre de enfermedad (HR 1.36; IC del 95%: 0.84-2.21, p = 0.22)Diseño retrospectivo, centro único de datos.Los pacientes con EII y sin EII con cáncer rectal tienen una supervivencia similar a largo plazo y libre de enfermedad, a pesar de las tasas más bajas de tratamiento sneoadyuvante y un mayor margen positivo en pacientes con EII. Consulte Video Resumen en http://links.lww.com/DCR/B271.

Interactions of Segmented Filamentous Bacteria (Candidatus Savagella) and bacterial drivers in colitis-associated colorectal cancer development

Colorectal cancer (CRC) risk is influenced by host genetics, sex, and the gut microbiota. Using a genetically susceptible mouse model of CRC induced via inoculation with pathobiont Helicobacter spp. and demonstrating variable tumor incidence, we tested the ability of the Th17-enhancing commensal Candidatus Savagella, more commonly denoted as Segmented Filamentous Bacteria (SFB), to influence the incidence and severity of colitis-associated CRC in male and female mice. To document the composition of the gut microbiota during CRC development and identify taxa associated with disease, fecal samples were collected before and throughout disease development and characterized via 16S rRNA sequencing. While there were no significant SFB-dependent effects on disease incidence or severity, SFB was found to exert a sex-dependent protective effect in male mice. Furthermore, SFB stabilized the GM against Helicobacter-induced changes post-inoculation, resulting in a shift in disease association from Helicobacter spp. to Escherichia coli. These data support sex-dependent SFB-mediated effects on CRC risk, and highlight the complex community dynamics within the GM during exposure to inflammatory pathobionts.

Analysis of colon-infiltrating γδ T cells in chronic inflammatory bowel disease and in colitis-associated cancer

Inflammatory bowel disease (IBD) remains a global health problem with a significant percentage of patients progressing to chronic inflammation and colitis-associated cancer (CAC). Whether or not γδ T cells contribute to initiation and maintenance of inflammation in IBD and in the development of CAC is not known. We have evaluated the frequency, phenotype, and functions of γδ T cells among tissue-infiltrating lymphocytes in healthy donors and IBD and CAC patients. Results show that Vδ1 T cells are the dominant γδ T-cell population in healthy tissue, whereas Vδ2 T significantly abound in chronic IBD. Vδ2 T cells produce more IFN-γ, TNF-α, and IL-17 than Vδ1 T cells in chronic inflamed IBD. In CAC patients no significant cytokine production was detected in tissue-resident Vδ1 T cells, but Vδ2 T cells produced remarkable amounts of IFN-γ and TNF-α; these data were confirmed by the analysis of an independent cohort of IBD transcriptomes. Moreover, transcriptomes of IBD patients revealed a clear-cut clusterization of genes related with the maintenance of the inflammatory status. In conclusion, our results demonstrating that Vδ2 T cells have a proinflammatory profile in chronic IBD are suggestive of their participation in IBD and CAC pathogenesis.

Interval Colorectal Cancer in Inflammatory Bowel Disease: The Role of Guideline Adherence

BACKGROUND

Factors associated with interval colorectal cancer (CRC) development in the inflammatory bowel disease (IBD) population remain unclear.

AIMS

Among a cohort of patients with interval CRC, we aimed to evaluate IBD characteristics, colonoscopy quality indicators, and surveillance guideline adherence.

METHODS

We performed a retrospective review of IBD- and non-IBD-associated interval CRCs diagnosed between January 2007 and December 2014 within a large US healthcare system. We evaluated risk factors for CRC among patients with IBD. We assessed adherence to surveillance guidelines according to the American Society for Gastrointestinal Endoscopy (IBD surveillance) and the US Multi-Society Task Force on Colorectal Cancer (polyp surveillance). We compared colonoscopy quality measures between patients with and without IBD.

RESULTS

Among 5345 cases of colonic adenocarcinoma, we detected 15 IBD-associated cases of interval CRC and 230 non-IBD-associated cases of interval CRC. Compared to patients without IBD, IBD patients were younger (54.5 vs. 70.4 years; p < 0.0001) and experienced a shorter interval between index colonoscopy and CRC diagnosis (20.7 vs. 35.1 months; p = 0.0009). Fifty three percent (8/15) of interval CRCs in IBD patients were detected within surveillance guidelines. All IBD patients with interval CRC detected after guideline surveillance interval had high-risk features, including active inflammation, previous low-grade or indefinite dysplasia, multiple pseudopolyps on index colonoscopy, or a first-degree relative with CRC. There were no differences in colonoscopy quality measures between patients with and without IBD.

CONCLUSIONS

This study stresses the importance of strict short-interval surveillance for IBD patients with high-risk features, including active inflammation on index colonoscopy.

The Evolving Role of Thiopurines in Inflammatory Bowel Disease

PURPOSE OF REVIEW

With the advent of biologic therapies for the treatment of inflammatory bowel disease, the roles of thiopurines have continued to evolve. This review will focus on recent advances in pharmacology and the safety and efficacy of thiopurines as maintenance therapies for steroid-induced remissions and post-surgical maintenance of remission and as combination therapies to reduce immunogenicities of biologic agents.

RECENT FINDINGS

Due to pharmacogenetics of thiopurine S-methyltransferase, thiopurine dosing is more effectively based on monitoring of thiopurine metabolites rather than weight-based dosing. Thiopurines continue to have a role as maintenance therapy after steroid-induced remissions and in combination with biologics to induce and maintain remission. Safety monitoring includes measurements of blood counts, liver chemistries, and dermatologic evaluations and protection from sun exposure. Thiopurines appear to be safe during pregnancies and while very uncommon, lymphomas (including hepatosplenic T cell lymphomas) remain a recognized risk, particularly in younger and older males.

IBD-associated Colon Cancers Differ in DNA Methylation and Gene Expression Profiles Compared With Sporadic Colon Cancers

BACKGROUND AND AIMS

As ulcerative colitis [UC]-associated colorectal cancer [CRC] and sporadic CRC differ in presentation and molecular features, we sought to evaluate differences in the impact of DNA methylation on gene expression.

METHODS

DNA methylation was assessed in 11 UC-CRCs and adjacent tissue and 11 sporadic CRCs and adjacent tissue, using Illumina arrays. RNA sequencing was performed on 10 UC-CRCs and adjacent tissue and eight sporadic CRCs and adjacent tissues. Differences in DNA methylation and transcript expression, as well as their correlation in the same tissues, were assessed. Immunohistochemistry was performed for three proteins, ANPEP, FAM92A1, and STK31, all of which exhibited an inverse correlation between DNA methylation and transcript expression in UC.

RESULTS

Thirty three loci demonstrated differences in DNA methylation between UC-CRC and adjacent tissue. In contrast, there were 4204 differentially methylated loci between sporadic colon cancer and adjacent tissue. Eight hundred eighty six genes as well as 10 long non-coding RNAs [lncRNA] were differentially expressed between UC-CRC and adjacent tissues. Although there were no differentially methylated loci between UC and sporadic CRC, 997 genes and 38 lncRNAs were differentially expressed between UC-CRC and sporadic CRC. In UC, 18 genes demonstrated a negative correlation between DNA methylation and transcript expression. Evaluation of protein expression related to three genes, ANPEP, FAM92A1, and STK31, confirmed down-regulation of ANPEP and up-regulation of STK31 in UC-CRC.

CONCLUSIONS

Regulation of transcript expression by DNA methylation involves genes key to colon carcinogenesis and may account for differences in presentation and outcomes between inflammatory bowel disease and sporadic colon cancer.

Colorectal cancer screening from 45 years of age: Thesis, antithesis and synthesis

Colorectal cancer incidence and mortality in patients younger than 50 years are increasing, but screening before the age of 50 is not offered in Europe. Advanced-stage diagnosis and mortality from colorectal cancer before 50 years of age are increasing. This is not a detection-bias effect; it is a real issue affecting the entire population. Three independent computational models indicate that screening from 45 years of age would yield a better balance of benefits and risks than the current start at 50 years of age. Experimental data support these predictions in a sex- and race-independent manner. Earlier screening is seemingly affordable, with minimal impediments to providing younger adults with colonoscopy. Indeed, the American Cancer Society has already started to recommend screening from 45 years of age in the United States. Implementing early screening is a societal and public health problem. The three independent computational models that suggested earlier screening were criticized for assuming perfect compliance. Guidelines and recommendations should be derived from well-collected and reproducible data, and not from mathematical predictions. In the era of personalized medicine, screening decisions might not be based solely on age, and sophisticated prediction software may better guide screening. Moreover, early screening might divert resources away from older individuals with greater biological risks. Finally, it is still unknown whether early colorectal cancer is part of a continuum of disease or a biologically distinct disease and, as such, it might not benefit from screening at all. The increase in early-onset colorectal cancer incidence and mortality demonstrates an obligation to take actions. Earlier screening would save lives, and starting at the age of 45 years may be a robust screening option.

27-hydroxycholesterol decreases cell proliferation in colon cancer cell lines

Colorectal cancer (CRC) is the third most diagnosed cancer in the western world, affecting 1 out of approximately 22 people in their lifetime. Several epidemiological studies suggest a positive association between high plasma cholesterol levels and colorectal cancer. However, the molecular mechanisms by which cholesterol may alter the risk of colorectal cancer (CRC) are ill-defined as the cholesterol lowering drugs statins do not appear to decrease a patient's risk of developing colorectal cancer. Cholesterol is metabolized to active derivatives including cholesterol oxidization products (COP), known as oxysterols, which have been shown to alter cellular proliferation. These metabolites and not cholesterol per se, may therefore affect the risk of developing colorectal cancer. The cholesterol metabolite or the oxysterol 27-hydroxycholesterol (27-OHC) is the most abundant oxysterol in the plasma and has been shown to be involved in the pathogenesis of several cancers including breast and prostate cancer. However, the role of 27-OHC in colorectal cancer has not been investigated. We treated Caco2 and SW620, two well characterized colon cancer cells with low, physiological and high concentrations of 27-OHC, and found that 27-OHC reduces cellular proliferation in these cells. We also found that the effects of 27-OHC on cell proliferation are not due to cellular cytotoxicity or apoptotic cellular death. Additionally, 27-OHC-induced reduction in cell proliferation is independent of actions on its target nuclear receptors, liver-X-receptors (LXR) and estrogen receptors (ER) activation. Instead, our study demonstrates that 27-OHC significantly decreases AKT activation, a major protein kinase involved in the pathogenesis of cancer as it regulates cell cycle progression, protein synthesis, and cellular survival. Our data shows that treatment with 27-OHC substantially decreases the activation of AKT by reducing levels of its active form, p-AKT, in Caco2 cells but not SW620 cells. All-together, our results show for the first time that the cholesterol metabolite 27-OHC reduces cell proliferation in colorectal cancer cells.

Role of IL-23 signaling in the progression of premalignant oral lesions to cancer

Mice bearing carcinogen-induced premalignant oral lesions were previously shown to have a pro-inflammatory phenotype, which is replaced with an immune inhibitory phenotype as lesions progress to cancer. Since Th17 cells are prominent at the premalignant lesion state and their levels are supported by IL-23, studies used mice that were IL-23 receptor deficient (IL-23R KO) to determine the requirement for IL-23 signaling in the immunological and clinical status of mice with premalignant oral lesions. The results showed a dependence on IL-23 signaling for the pro-inflammatory state of mice with oral lesions as levels of IL-2, IFN-γ, IL-6, IL-17 and TNF-α were elevated in wildtype mice with premalignant oral lesions, but not in IL-23R KO mice. In contrast, as lesions progressed to cancer, the pro-inflammatory phenotype subsided and was replaced with the inhibitory mediator IL-10 and with Treg cells in wildtype mice, although not in IL-23R KO mice. Clinically, early progression of premalignant oral lesions to cancer was enhanced in IL-23R KO mice compared to progression in wildtype mice. These results show the importance of IL-23 signaling in both the pro-inflammatory phenotype characteristic of premalignant oral lesions and the inhibitory phenotype as lesions progress to cancer.

Short-chain fatty acids administration is protective in colitis-associated colorectal cancer development

Reduced short-chain fatty acids (SCFAs) have been reported in patients with ulcerative colitis, and increased intake of dietary fiber has shown to be clinically beneficial for colitis. Whether SCFAs suppress tumorigenesis in colitis-associated colorectal cancer remains unknown. The chemopreventive effect of SCFAs in colitis-associated colorectal cancer was evaluated in this study. Model of colitis-associated colorectal cancer in male BALB/c mice was induced by azoxymethane (AOM) and dextran sodium sulfate (DSS). SCFAs mix (67.5 mM acetate, 40 mM butyrate, 25.9 mM propionate) was administered in drink water during the study period. Macroscopic and histological studies were performed to examine the colorectal inflammation and tumorigenesis in AOM/DSS-induced mice treated with or without SCFA mix. The effects of SCFAs mix on colonic epithelial cellular proliferation were also assessed using Ki67 immunohistochemistry and TUNEL staining. The administration of SCFAs mix significantly reduced the tumor incidence and size in mice with AOM/DSS-induced colitis associated colorectal cancer. SCFAs mix protected from AOM/DSS-induced colorectal cancer by improving colon inflammation and disease activity index score as well as suppressing the expression of proinflammatory cytokines including IL-6, TNF-α and IL-17. A decrease in cell proliferation markers and an increase in TUNEL-positive tumor epithelial cells were also demonstrated in AOM/DSS mice treated with SCFAs mix. SCFAs mix administration prevented development of tumor and attenuated the colonic inflammation in a mouse model of colitis-associated colorectal cancer. SCFAs mix may be a potential agent in the prevention and treatment of colitis-associated colorectal cancer.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The Natural History of IBD: Lessons Learned

PURPOSE OF REVIEW

Inflammatory bowel diseases (IBD), which include Crohn's disease (CD) and ulcerative colitis (UC), are chronic, relapsing diseases with unknown etiologies. The purpose of this review is to present the natural disease course evidenced in the latest epidemiology data.

RECENT FINDINGS

The prevalence of IBD is rapidly increasing, affecting five million patients worldwide with the highest incidence observed in Northern Europe and Northern America. It has been shown that both CD and UC patients are at an increased risk for developing cancer of the gastrointestinal tract compared to the general population. Though the disease course of IBD is unpredictable, the rate of surgical treatment has declined potentially as a consequence of the introduction of immunomodulators and new biologic treatment options. Treatments with biological agents and/or immunosuppressive drugs as well as disease monitoring with eHealth devices seem to have a positive impact on the disease course. However, long-term follow-up studies are still lacking and therefore no reliable conclusions can be drawn as of yet. Medical compliance is paramount in the treatment of IBD, and continuous research focusing on approaches that increase compliance is also necessary.

Clinical characteristics of ulcerative colitis-related colorectal cancer in Chinese patients

OBJECTIVE

The prevalence of ulcerative colitis (UC) in China has been increasing, together with the incidence of ulcerative colitis-related colorectal cancer (UCRCC). In this study we aimed to investigate the clinical features of UCRCC in Chinese UC patients.

METHODS

Clinical data of patients with UCRCC during January 2003 to December 2016 were retrieved from the Peking Union Medical College Hospital registration database and compared with that of sporadic colorectal cancer (CRC).

RESULTS

During the study period, among the 10 110 patients with CRC 25 were found to have UCRCC, with an average age of 51 years and a median disease duration of 15 years. The cumulative prevalence of UCRCC was 0.25% in all CRC patients, with a significant increase from 2003-2007 to 2013-2016 (P < 0.01). Altogether 14 (56.0%) patients with UCRCC were men, and 5 (20.0%) had a family history of UC or cancer. Four (16.0%) patients had concurrent high-grade intraepithelial neoplasia with variable differentiated adenocarcinoma at other sites and 19 (59.4%) tumors were moderately or poorly differentiated. Twenty-three (92.0%) patients underwent surgery, of whom 10 (40%) were at stage III and IV according to the TNM staging system. Compared with the 10 085 patients with sporadic CRC, UCRCC patients were younger (P < 0.01) and were more likely to have descending colon involvement and multifocal lesions (P < 0.01).

CONCLUSIONS

UCRCC patients have been increasing in recent years. Compared with patients with sporadic CRC, those with UCRCC are younger and are more likely to have descending colon involvement and multifocality.

Inflammatory Bowel Disease Adversely Impacts Colorectal Cancer Surgery Short-term Outcomes and Health-Care Resource Utilization

Objectives:

Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (CRC) compared to patients without IBD. There is a lack of population-based data evaluating the in-patient surgical outcomes of CRC in IBD patients. We sought to compare the hospital outcomes of CRC surgery between patients with and without IBD.

Methods:

We used the National Inpatient Sample (2008–2012) and Nationwide Readmissions Database (NRD, 2013) and selected all adult patients (age ≥18 years) with ulcerative colitis (UC) or Crohn’s disease (CD) who underwent CRC surgery. Multivariate analysis for in-patient outcomes of postoperative complications, health-care resource utilization, readmission rate, and mortality were performed.

Results:

A total of 397,847 patients underwent CRC surgery from 2008 to 2012, of which 0.8% (3,242) had IBD. Compared to CRC in non-IBD patients, CRC in IBD patients had longer length of stay (adjusted coefficient (AC) 0.86 days, 95% confidence interval (CI): 0.42, 1.30), more likely developed postoperative complications (adjusted odds ratio (AOR) 1.26, 95% CI: 1.06, 1.50), including postoperative infection (AOR 1.69, 95% CI: 1.20, 2.38) and deep vein thrombosis (AOR 2.42, 95% CI: 1.36, 4.28), and more frequently required blood transfusion (AOR 1.59, 95% CI: 1.30, 1.94). CRC in IBD patients was more likely to be readmitted within 30 days (AOR 1.44, 95% CI: 1.01, 2.04).

Conclusion:

At a population level, IBD adversely impacts outcomes at the time of CRC surgery.

Redirecting the focus of cancer immunotherapy to premalignant conditions

Much progress has been made in introducing immunological treatment approaches for cancer, with lessons learned from both the successes and failures of immunotherapy. Among the challenges of immunotherapeutic approaches for cancer are the multitudes of mechanisms by which cancers are known to subvert the immune defenses. This has led to the incorporation into the immunotherapeutic arsenal strategies by which to overcome the cancer’s immunological blockades. What has been only superficially explored is the immunological milieu of premalignant lesions and the possibility of immunological approaches for the treatment of premalignant lesions so as to prevent secondary premalignant lesions and their progression to cancer. This review discusses the immunological environment associated with premalignant lesions, and the possible missed opportunity of utilizing immunological treatment strategies in the less hostile environment of premalignant lesions as compared to the immune subversive cancer environment.