5-Aminosalicylate use and colorectal cancer risk in inflammatory bowel disease: a large epidemiological study

Adherence to systemic therapies for immune-mediated inflammatory diseases in Lebanon: a physicians' survey from three medical specialties

BACKGROUND

Immune-mediated inflammatory diseases (IMIDs) are chronic conditions that may cause tissue damage and disability, reduced quality of life and increased mortality. Various treatments have been developed for IMIDs, including immune modulators and targeted biologic agents. However, adherence remains suboptimal.

METHODS

An adherence survey was used to evaluate physicians' beliefs about adherence to medication in IMID and to evaluate if and how they manage adherence. The survey was distributed to 100 randomly selected physicians from three different specialties. Results were analyzed by four academic experts commissioned to develop an action plan to address practical and perceptual barriers to adherence, integrating it into treatment goals to maximize outcomes in IMID, thereby elevating local standards of care.

RESULTS

Eighty-two physicians participated in this study and completed the questionnaire. Most defined adherence as compliance with prescribed treatment. Although the majority of surveyed physicians (74%) did not systematically measure adherence in their practice, 54% identified adherence as a treatment goal of equal or greater importance to therapeutic endpoints. Lack of time and specialized nursing support was reported as an important barrier to measuring adherence. The expert panel identified four key areas for action: 360° education (patient-nurse-physician), patient-physician communication, patient perception and concerns, and market access/cost. An action plan was developed centered on education and awareness, enhanced benefit-risk communication, development of adherence assessment tools and promotion of patient support programs.

CONCLUSION

Nonadherence to medication is a commonly underestimated problem with important consequences. A customized target-based strategy to address the root causes of non-adherence is essential in the management of chronic immune-mediated diseases.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Folic Acid Supplementation May Reduce Colorectal Cancer Risk in Patients With Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

GOALS

To evaluate the role of folic acid supplementation in colorectal cancer (CRC) chemoprevention in patients with inflammatory bowel disease (IBD).

BACKGROUND

CRC is a serious complication of IBD. Folic acid supplementation has been shown to be chemopreventative in sporadic CRC. Patients with IBD are at risk of folate deficiency though intestinal malabsorption and also competitive inhibition by concurrent sulfasalazine use. To date, there have been several studies reporting on folic acid supplementation in patients with IBD and CRC.

STUDY

We searched electronic databases for studies reporting folic acid use and CRC incidence in patients with IBD. We produced a pooled hazard ratio with 95% confidence intervals using a random-effects model. Preplanned subgroup analyses were performed to explore for any potential sources of heterogeneity.

RESULTS

Ten studies reporting on 4517 patients were included. We found an overall protective effect for folic acid supplementation on the development of CRC, pooled hazard ratio=0.58 (95% confidence interval, 0.37-0.80). There was low to moderate heterogeneity among studies, I=29.7%. Subgroup analyses suggested that folic acid use was protective in hospital-based studies, studies from North America and those that were performed before folate fortification of foods in 1998.

CONCLUSIONS

CRC remains an important complication of IBD. Chemoprevention is an attractive strategy and folic acid as a cheap, safe, and well-tolerated supplement may have a role. Focused prospective studies are required to precisely define any potential effect.

Chemoprevention of colorectal cancer in inflammatory bowel disease

INTRODUCTION

Patients with inflammatory bowel disease are at an increased risk of colorectal cancer when compared to the general population. Chronic inflammation is thought to be the underlying cause, and medications that reduce inflammation have the potential to reduce the risk of colorectal cancer. Areas covered: After conducting a PubMed search for relevant literature, we examined several classes of medications that have been studied as potential chemopreventive agents. These include 5-aminosalicylates, thiopurines, tumor necrosis factor antagonists, ursodeoxycholic acid, NSAIDs, and statins. Expert commentary: While each class of medications has some data to support its use in chemoprevention, the majority of the evidence in each case argues against the routine use of these medications solely for a chemopreventive benefit.

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

BACKGROUND AND AIMS

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

RESULTS

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

MATERIALS AND METHODS

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

CONCLUSIONS

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

The problem of adherence to therapy in ulcerative colitis and the potential utility of multi-matrix system (MMX) technology

Ulcerative colitis (uc) is a chronic condition and for the vast majority of patients, life-long treatment is required. low adherence to therapy is an emerging issue. since low adherence is associated with poor clinical outcomes and increased costs, it is becoming crucial to identify strategies in order to improve it. Areas covered: We performed literature searches in PubMed using the terms 'adherence', 'mesalamine', 'budesonide MMX', 'MMX technology' in combination with 'ulcerative colitis'. Firstly, we present the key-concepts of therapy for UC and discuss the problem of the adherence and how to measure it. Then, we provide data on the extent of the problem and the causes and consequences from clinical and economic point of views. Finally, we focus on treatment-related variables associated with non-adherence and treatment-related strategies to improve adherence, paying particular attention to Multi Matrix system (MMX) technology applied to mesalazine and budesonide. Expert commentary: The pharmaceutical industry and scientific community are making efforts to simplify treatments for UC. MMX technology, which allows a reduction in the number of pills to be taken and daily administrations, may facilitate adherence to treatment and carry further clinical benefits.

A population-based study examining the risk of malignancy in patients diagnosed with inflammatory bowel disease

BACKGROUND

Recent studies suggest an increased risk of malignancy in patients with inflammatory bowel disease (IBD), although the findings were inconsistent. We used data from the clinical practice research datalink (CPRD) to further examine this association.

METHODS

Patients with a first-time diagnosis of IBD were randomly matched to an equally sized IBD-free comparison group. Multivariable adjusted hazard ratios (AHRs) for cancer risk were estimated using Cox's proportional hazard regression. A nested case-control analysis comprising IBD patients only was then conducted using conditional logistic regression to estimate the risk of cancer development according to IBD severity, disease duration and IBD therapy.

RESULTS

We identified 1077 cancers among 39,294 IBD or IBD-free patients followed between 1995 and 2012. There was no association between IBD and overall risk of cancer [AHR 1.11, 95 % confidence interval (CI) 0.98-1.25], but a borderline increase in the risk of lymphoproliferative malignancies was observed in patients with IBD (AHR 1.49, 95 % CI 1.00-2.23). Aminosalicylate use was significantly associated with reduced risk of all cancers [adjusted odds ratio (AOR), 0.72, 95 % CI 0.54-0.96], of intestinal cancer (AOR 0.33, 95 % 0.12-0.89) and of prostate cancer (AOR 0.32, 95 % 0.13-0.80).

CONCLUSIONS

There was no increased risk of cancer overall in individuals with IBD compared to IBD-free individuals. Consistent with previous findings, a reduction in cancer risk was observed in IBD patients using aminosalicylates, with a substantial reduction in prostate cancer risk. Further large-scale studies examining the relationship between IBD therapy and cancer risk appear to be warranted.

Total and cancer mortality in a cohort of ulcerative colitis and Crohn's disease patients: The Florence inflammatory bowel disease study, 1978-2010

BACKGROUND

There is no consensus on the leading causes of death among inflammatory bowel diseases (IBD) patients.

AIM

We present the results of an extended follow-up of the population-based Florence IBD cohort, including 689 ulcerative colitis and 231 Crohn's disease patients.

METHODS

The causes of death of cohort members were determined through linkage with the local mortality registry. We calculated standardized mortality ratios (SMR) and 95% confidence intervals (95%CI) by applying gender-, age- and calendar time-death rates to person-years at risk.

RESULTS

Ulcerative colitis patients had overall mortality comparable to the general population (SMR 0.99, 95%CI 0.85-1.14), though being at increased risk of dying from Hodgkin's disease (SMR 11.74, 95%CI 2.94-46.94), rectal cancer (SMR 3.69, 95%CI 1.66-8.22) and Alzheimer's disease (2.40, 95%CI 1.00-5.76). Crohn's disease patients had an increased overall mortality (SMR 1.79, 95%CI 1.39-2.27) and were at higher risk of dying from cancer (SMR 2.57, 95%CI 1.28-5.13) and non-cancer diseases of the respiratory system (SMR 2.51, 95%CI 1.05-6.04), brain cancer (SMR 6.26, 95%CI 1.57-25.02) and non-cancer diseases of the genitourinary system (SMR 4.38, 95%CI 1.10-17.52).

CONCLUSIONS

IBD patients should be offered counselling on risk reduction strategies, as much of their mortality excess is potentially avoidable.

Steroid dependency and trends in prescribing for inflammatory bowel disease - a 20-year national population-based study

BACKGROUND

It is unclear whether adherence to prescribing standards has been achieved in inflammatory bowel disease (IBD).

AIM

To determine how prescribing of 5-aminosalicylates (5-ASAs), steroids and thiopurines has changed in response to emerging evidence.

METHODS

We examined trends in oral and topical therapies in 23 509 incident IBD cases (6997 with Crohn's disease and 16 512 with ulcerative colitis) using a nationally representative sample between 1990 and 2010. We created five eras according to the year of diagnosis: era 1 (1990-1993), era 2 (1994-1997), era 3 (1998-2001), era 4 (2002-2005) and era 5 (2006-2010). We calculated the proportion of patients treated with prolonged 5-ASAs (>12 months) and steroid dependency, defined as prolonged steroids (>3 months) or recurrent (restarting within 3 months) steroid exposure. We calculated the cumulative probability of receiving each medication using survival analysis.

RESULTS

Half of the Crohn's disease patients were prescribed prolonged oral 5-ASAs during the study, although this decreased between era 3 and 5 from 61.8% to 56.4% (P = 0.002). Thiopurine use increased from 14.0% to 47.1% (P < 0.001) between era 1 and 5. This coincided with a decrease in steroid dependency from 36.5% to 26.8% (P < 0.001) between era 1 and 2 and era 4 and 5 respectively. In ulcerative colitis, 49% of patients were maintained on prolonged oral 5-ASAs. Despite increasing thiopurine use, repeated steroid exposure increased from 15.3% to 17.8% (P = 0.02) between era 1 and 2 and era 4 and 5 respectively.

CONCLUSIONS

Prescribing in clinical practice insufficiently mirrors the evidence base. Physicians should direct management towards reducing steroid dependency and optimising 5-ASA use in patients with IBD.

Sulfasalazine, a therapeutic agent for ulcerative colitis, inhibits the growth of CD44v9(+) cancer stem cells in ulcerative colitis-related cancer

BACKGROUND AND OBJECTIVE

Sulfasalazine reduces the risk of ulcerative colitis (UC)-related cancer through its anti-inflammatory effect and induction of oxidative stress in cancer cells by inhibiting the glutamate-cystine transporter, which is closely associated with the cancer stem cell surface marker CD44v9. This study aimed to quantify the effects of sulfasalazine on CD44v9 expression and pathological factors in colorectal cancers (CRCs) arising from UC.

METHODS

Twenty-six patients with UC-related cancer were classified into groups according to the length of sulfasalazine treatment as follows: (1) long-term (LT) (≥ 5 years) and (2) short-term (ST) (< 5 years). Using immunohistochemistry, we compared CD44v9 and Ki-67 expression and pathological characteristics of each group's tumors. In vitro assay was performed to investigate the effect of sulfasalazine on epithelial differentiation and proliferation of CD44(+) cancer cells.

RESULTS

Immunohistochemical analysis revealed that CD44v9 expression tended to be lower in the LT group (LT:ST=15.4%:46.2%, P=0.20), and Ki-67/CD44v9 double-stained cells were significantly lower in the LT group (LT:ST=0%:6.9%, P=0.01). Pathologically, the frequency of well-differentiated adenocarcinomas was higher in the LT group (LT:ST=84.6%:38.5%, P=0.04). In vitro assay revealed that sulfasalazine promoted the expression of epithelial differentiation markers (E-cadherin and CDX2) and inhibited the proliferation of CD44(+) cancer cells.

CONCLUSIONS

Long-term sulfasalazine administration reduced proliferative CD44v9(+) cells and increased the degree of differentiation of adenocarcinomas. These findings indicate the importance of CD44v9(+) cells in UC-related cancer progression and suggest that sulfasalazine may serve as a novel therapeutic agent that targets CD44v9(+) cells.

Importance of the alternative NF-κB activation pathway in inflammation-associated gastrointestinal carcinogenesis

Chronic inflammation is a common factor in the development of many gastrointestinal malignancies. Examples include inflammatory bowel disease predisposing to colorectal cancer, Barrett's esophagus as a precursor of esophageal adenocarcinoma, and Helicobacter pylori-induced gastric cancer. The classical activation pathway of NF-κB signaling has been identified as regulating several sporadic and inflammation-associated gastrointestinal tract malignancies. Emerging evidence suggests that the alternative NF-κB signaling pathway also exerts a distinct influence on these processes. This review brings together current knowledge of the role of the alternative NF-κB signaling pathway in the gastrointestinal tract, with a particular emphasis on inflammation-associated cancer development.

Does aspirin or non-aspirin non-steroidal anti-inflammatory drug use prevent colorectal cancer in inflammatory bowel disease?

AIM: To determine whether aspirin or non-aspirin non-steroidal anti-inflammatory drugs (NA-NSAIDs) prevent colorectal cancer (CRC) in patients with inflammatory bowel disease (IBD).

METHODS: We performed a systematic review and meta-analysis. We searched for articles reporting the risk of CRC in patients with IBD related to aspirin or NA-NSAID use. Pooled odds ratios (OR) and 95%CIs were determined using a random-effects model. Publication bias was assessed using Funnel plots and Egger’s test. Heterogeneity was assessed using Cochran’s Q and the I² statistic.

RESULTS: Eight studies involving 14917 patients and 3 studies involving 1282 patients provided data on the risk of CRC in patients with IBD taking NA-NSAIDs and aspirin respectively. The pooled OR of developing CRC after exposure to NA-NSAIDs in patients with IBD was 0.80 (95%CI: 0.39-1.21) and after exposure to aspirin it was 0.66 (95%CI: 0.06-1.39). There was significant heterogeneity (I² > 50%) between the studies. There was no change in the effect estimates on subgroup analyses of the population studied or whether adjustment or matching was performed.

CONCLUSION: There is a lack of high quality evidence on this important clinical topic. From the available evidence NA-NSAID or aspirin use does not appear to be chemopreventative for CRC in patients with IBD.

Thiopurine Therapy Reduces the Incidence of Colorectal Neoplasia in Patients with Ulcerative Colitis. Data from the ENEIDA Registry

BACKGROUND AND AIMS

Patients with ulcerative colitis (UC) are at increased risk of developing colorectal cancer (CRC), but recent studies suggest a lower risk than previously reported. The aim was to evaluate the incidence of dysplasia, CRC and related risk factors in UC patients from a Spanish nationwide database.

METHODS

All UC patients were identified and retrospectively reviewed. Clinical-epidemiological data and the finding of dysplasia and/or CRC were collected.

RESULTS

A total of 831 UC patients were included. Twenty-six cases of CRC in 26 patients and 29 cases of high-grade dysplasia (HGD) in 24 patients were found, accounting for 55 diagnoses of advanced neoplasia (AN = CRC and/or HGD) in 45 patients (33% of them within the first 8 years after UC diagnosis). The cumulative risk of AN was 2, 5.3 and 14.7% at 10, 20 and 30 years, respectively. Concomitant primary sclerosing cholangitis (odds ratio [OR] 10.90; 95% confidence interval [CI] 3.75-31.76, p < 0.001), extensive UC (OR 2.10, 95% CI 1.01-4.38, p = 0.048), UC diagnosis at an older age (OR 2.23, 95% CI 1.03-4.83, p = 0.043) and appendectomy prior to UC diagnosis (OR 2.66, 95% CI 1.06-6.71, p = 0.038) were independent risk factors for AN. Use of thiopurines (OR 0.21, 95% CI 0.06-0.74, p = 0.015) and being in a surveillance colonoscopy programme (OR 0.33; 95% CI 0.16-0.67; p = 0.002) were independent protective factors for AN.

CONCLUSIONS

The risk of AN among UC patients is lower than previously reported but steadily increases from the time of UC diagnosis. The widespread use of thiopurines may have influenced this reduced incidence of UC-related neoplasias.

Mesalamine, but Not Sulfasalazine, Reduces the Risk of Colorectal Neoplasia in Patients with Inflammatory Bowel Disease: An Agent-specific Systematic Review and Meta-analysis

BACKGROUND

In some studies, 5-aminosalicylates as a class have been associated with protective effects against colorectal cancer in inflammatory bowel disease. In practice, only mesalamine at doses greater than 1.2 g per day is currently widely in this setting. The specific impact of mesalamine at these doses has not has not previously been determined.

METHODS

We performed a systematic review and meta-analysis of the effect of mesalamine on risk of colorectal neoplasia (CRN) from prior cohort and case-control studies. Sensitivity analyses for study setting and case definition were performed. A quality assessment was made of all included studies.

RESULTS

Mesalamine was associated with a modest reduction in the odds ratio (OR) of CRN (OR = 0.6, 95% confidence interval, 0.4-0.9, P = 0.04). This effect was only noted in hospital-based studies and only in the reduction of all CRN (not cancers alone). Patients prescribed doses >1.2 g per day had a lower risk of CRN (OR = 0.5, 95% confidence interval, 0.3-0.9, P = 0.02) than lower doses. This effect was also only present in the hospital-based studies. In contrast, there was no reduction in the risk of CRN in patients prescribed sulfasalazine (OR = 0.8, 95% confidence interval, 0.5-1.2, P = 0.3), regardless of study setting.

CONCLUSIONS

Mesalamine, particularly at doses >1.2 g per day, produces a modest reduction in the risk of CRN in inflammatory bowel disease patient populations from referral centers. Sulfasalazine does not seem to reduce the risk. No benefit was noted in population-based studies.

Inflammatory Bowel Disease: An Overview of Immune Mechanisms and Biological Treatments

Inflammatory bowel diseases (IBD) are characterized by chronic inflammation of the intestinal tract associated with an imbalance of the intestinal microbiota. Crohn's disease (CD) and ulcerative colitis (UC) are the most widely known types of IBD and have been the focus of attention due to their increasing incidence. Recent studies have pointed out genes associated with IBD susceptibility that, together with environment factors, may contribute to the outcome of the disease. In ulcerative colitis, there are several therapies available, depending on the stage of the disease. Aminosalicylates, corticosteroids, and cyclosporine are used to treat mild, moderate, and severe disease, respectively. In Crohn's disease, drug choices are dependent on both location and behavior of the disease. Nowadays, advances in treatments for IBD have included biological therapies, based mainly on monoclonal antibodies or fusion proteins, such as anti-TNF drugs. Notwithstanding the high cost involved, these biological therapies show a high index of remission, enabling a significant reduction in cases of surgery and hospitalization. Furthermore, migration inhibitors and new cytokine blockers are also a promising alternative for treating patients with IBD. In this review, an analysis of literature data on biological treatments for IBD is approached, with the main focus on therapies based on emerging recombinant biomolecules.

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.

Peroxisome proliferator-activated receptor-γ is downregulated in ulcerative colitis and is involved in experimental colitis-associated neoplasia

The aim of the present study was to evaluate the expression of peroxisome proliferator-activated receptor (PPAR)-γ in inflammatory bowel disease (IBD), and to also identify the association between PPAR-γ and the clinical features of patients with IBD. An azoxymethane (AOM)/dextran sodium sulfate (DSS) animal model of colitis-associated neoplasia was established to investigate the protective effect of 5-aminosalicylic acid (5-ASA) and to explore the changes in the expression of PPAR-γ during this process. A total of 66 specimens of colorectal tissue obtained from biopsy performed on IBD patients and 30 healthy control individuals were immunohistochemically stained for PPAR-γ. An AOM/DSS animal model of colitis-associated neoplasia was then established. Reverse transcription quantitative polymerase chain reaction was conducted and it was found that, compared with the control group and patients with Crohn's disease (CD), the expression of PPAR-γ in the intestinal tissue of patients with ulcerative colitis (UC) was significantly decreased (P=0.027 and 0.046, respectively). The expression of PPAR-γ was found to be negatively associated with the disease activity of UC and was not associated with the severity of disease, site of lesions or CD characteristics. Administration of 5-ASA decreased the colitis and tumor burden of colons. The expression level of PPAR-γ in the intestinal tissue was also increased in the AOM/DSS/5-ASA group compared with AOM/DSS group (P<0.001). PPAR-γ is an important factor in the pathogenesis of UC and colitis-associated cancer. The present study found that 5-ASA significantly alleviates the colitis and tumor burden in a mouse model of AOM/DSS-induced colitis-associated neoplasia, and promotes the expression of PPAR-γ in the intestinal tract.

Chemopreventive effects of 5-amino salicylic acids on inflammatory bowel disease-associated colonic cancer and colonic dysplasia: a meta-analysis

PURPOSE

To study the effects of 5-amino salicylic acids (5-ASAs) on the incidence rates of inflammatory bowel disease (IBD)-associated colonic cancer (IBDACa) and colonic dysplasia (IBDADys), as well as to evaluate the chemopreventive effects of 5-ASAs on IBDACa/Dys.

METHODS

Searches for officially published clinical studies on the effects of 5-ASAs on the chemoprevention of IBDACa/Dys were conducted in both foreign-language databases, including PubMed (Medline), EMCC, OVID, and the Cochrane Library, and Chinese databases, including Wanfang, Weipu (VIP), and CNKI, as well as using Google Scholar. For literature matching the selection criteria, the statistical software RevMan was employed to calculate odds ratio (OR) values and 95% confidence intervals (CIs). Sub-group analysis was performed for different study design types and IBD types.

RESULTS

A total of fourteen papers were included in this study. The results of the analysis showed that compared with patients not using 5-ASAs, patients using 5-ASAs showed only 49% of the occurrence rate of IBDACa and IBDADys, OR = 0.49 (95% CI: 0.33-0.73). The OR of ulcerative colitis (UC) patients using 5-ASAs exhibiting UCCa/Dys was 0.44 (95% CI: 0.26-0.76).

CONCLUSION

The use of 5-ASAs exerts a chemopreventive effect against IBDACa/Dys.

Chemoprevention of colorectal cancer

Colorectal cancer has become one of the most prevalent malignant diseases for both men and women. Patients with inflammatory bowel diseases or certain inherited cancer syndromes are at high risk of developing colorectal cancer and have naturally the highest need for cancer prevention. In familial adenomatous polyposis (FAP) and Lynch syndrome, most of the underlying germline mutations can be detected by DNA sequencing, and medical counselling of affected individuals involves both surveillance tests and chemopreventive measures. However, as the mechanisms leading to colorectal cancer differ in these high-risk groups, the molecular action of chemopreventive drugs needs to be adjusted to the certain pathway of carcinogenesis. In the last decades, a number of drugs have been tested, including sulindac, aspirin, celecoxib, and mesalazine, but some of them are still controversially discussed. This review summarizes the advances and current standards of colorectal cancer prevention in patients with inflammatory bowel disease, FAP and Lynch syndrome.

Ulcerative colitis-associated colorectal cancer

The association between ulcerative colitis (UC) and colorectal cancer (CRC) has been acknowledged. One of the most serious and life threatening consequences of UC is the development of CRC (UC-CRC). UC-CRC patients are younger, more frequently have multiple cancerous lesions, and histologically show mucinous or signet ring cell carcinomas. The risk of CRC begins to increase 8 or 10 years after the diagnosis of UC. Risk factors for CRC with UC patients include young age at diagnosis, longer duration, greater anatomical extent of colonic involvement, the degree of inflammation, family history of CRC, and presence of primary sclerosing cholangitis. CRC on the ground of UC develop from non-dysplastic mucosa to indefinite dysplasia, low-grade dysplasia, high-grade dysplasia and finally to invasive adenocarcinoma. Colonoscopy surveillance programs are recommended to reduce the risk of CRC and mortality in UC. Genetic alterations might play a role in the development of UC-CRC. 5-aminosalicylates might represent a favorable therapeutic option for chemoprevention of CRC.

Colon cancer screening and surveillance in inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) have an increased risk of developing colorectal cancer (CRC). Accordingly, the duration and anatomic extent of the disease have been known to affect the development of IBD-related CRC. When CRC occurs in patients with IBD, unlike in sporadic CRC, it is difficult to detect the lesions because of mucosal changes caused by inflammation. In addition, the tumor types vary with ill-circumscribed lesions, and the cancer is difficult to diagnose and remedy at an early stage. For the diagnosis of CRC in patients with IBD, screening endoscopy is recommended 8 to 10 years after the IBD diagnosis, and surveillance colonoscopy is recommended every 1 to 2 years thereafter. The recent development of targeted biopsies using chromoendoscopy and relatively newer endoscopic techniques helps in the early diagnosis of CRC in patients with IBD. A total proctocolectomy is advisable when high-grade dysplasia or multifocal low-grade dysplasia is confirmed by screening endoscopy or surveillance colonoscopy or if a nonadenoma-like dysplasia-associated lesion or mass is detected. Currently, pharmacotherapies are being extensively studied as a way to prevent IBD-related CRC.

Colitis-associated neoplasia: molecular basis and clinical translation

Crohn's disease and ulcerative colitis are both associated with an increased risk of inflammation-associated colorectal carcinoma. Colitis-associated cancer (CAC) is one of the most important causes for morbidity and mortality in patients with inflammatory bowel diseases (IBD). Colitis-associated neoplasia distinctly differs from sporadic colorectal cancer in its biology and the underlying mechanisms. This review discusses the molecular mechanisms of CAC and summarizes the most important genetic alterations and signaling pathways involved in inflammatory carcinogenesis. Then, clinical translation is evaluated by discussing new endoscopic techniques and their contribution to surveillance and early detection of CAC. Last, we briefly address different types of concepts for prevention (i.e., anti-inflammatory therapeutics) and treatment (i.e., surgical intervention) of CAC and give an outlook on this important aspect of IBD.

The therapeutic value of targeting inflammation in gastrointestinal cancers

Inflammation has been implicated in the initiation and progression of gastrointestinal (GI) cancers. Inflammation also plays important roles in subverting immune tolerance, escape from immune surveillance, and conferring resistance to chemotherapeutic agents. Targeting key regulators and mediators of inflammation represents an attractive strategy for GI cancer prevention and treatment. However, the targeting of inflammation in GI cancer is not straightforward and sometimes inflammation may contribute to tumor regression. We discuss the origins and effects of inflammation in GI cancer and how to target it successfully.

5-Aminosalicylates reduce the risk of colorectal neoplasia in patients with ulcerative colitis: an updated meta-analysis

Background

Although the chemopreventive effect of 5-aminosalicylates on patients with ulcerative colitis has been extensively studied, the results remain controversial. This updated review included more recent studies and evaluated the effectiveness of 5-aminosalicylates use on colorectal neoplasia prevention in patients with ulcerative colitis.

Methods

Up to July 2013, we searched Medline, Embase, Web of Science, Cochrane CENTRAL, and SinoMed of China for all relevant observational studies (case-control and cohort) about the effect of 5-aminosalicylates on the risk of colorectal neoplasia among patients with ulcerative colitis. The Newcastle-Ottawa Scale was used to assess the quality of studies. Adjusted odds ratios (ORs) were extracted from each study. A random-effects model was used to generate pooled ORs and 95% confidence intervals (95%CI). Publication bias and heterogeneity were assessed.

Results

Seventeen studies containing 1,508 cases of colorectal neoplasia and a total of 20,193 subjects published from 1994 to 2012 were analyzed. 5-aminosalicylates use was associated with a reduced risk of colorectal neoplasia in patients with ulcerative colitis (OR 0.63; 95%CI 0.48–0.84). Pooled OR of a higher average daily dose of 5-aminosalicylates (sulfasalazine ≥ 2.0 g/d, mesalamine ≥ 1.2 g/d) was 0.51 [0.35–0.75]. Pooled OR of 5-aminosalicylates use in patients with extensive ulcerative colitis was 1.00 [0.53–1.89].

Conclusion

Our pooled results indicated that 5-aminosalicylates use was associated with a reduced risk of colorectal neoplasia in patients with ulcerative colitis, especially in the cases with a higher average daily dose of 5-aminosalicylates use. However, the chemopreventive benefit of 5-aminosalicylates use in patients with extensive ulcerative colitis was limited.

[Chemoprevention of colorectal cancer in inflammatory bowel disease]

The risk of developing colorectal cancer is increased in patients with inflammatory bowel disease. Surveillance colonoscopy has not been shown to prolong survival and rates of interval cancer are reported to be high. Continuing colonic inflammation has been shown to be important in the development of colorectal cancer and therefore anti-inflammatory agents such as the 5-aminosalicylates and immunomodulators have been considered as potential chemopreventive agents. This review focuses on various chemopreventive agents that have been clearly shown to reduce the risk of colorectal adenoma and cancer in the patients with inflammatory bowel disease.

Colorectal cancer in inflammatory bowel disease: results of the 3rd ECCO pathogenesis scientific workshop (I)

Epidemiological studies demonstrate an increased risk of colorectal cancer in patients with inflammatory bowel disease (IBD). A detailed literature review was conducted on epidemiology, risk factors, pathophysiology, chemoprevention and outcomes of colorectal cancer (CRC) in IBD as part of the 3rd ECCO scientific pathogenesis workshop.

5-Aminosalicylic acid and chemoprevention: does it work?

5-Aminosalicylic acid (5-ASA)-containing drugs are the mainstay of therapy in inflammatory bowel disease (IBD). Intestinal inflammation is the main risk factor for colorectal cancer (CRC) in IBD. Hence, all drugs that are able to induce and maintain mucosal healing (MH) may prevent CRC risk in IBD. In patients with mild to moderate ulcerative colitis (UC), a recent systematic review of 5-ASA trials demonstrated that MH was achieved in nearly 50% of patients. A systematic review including 48 studies linked 5-ASA chemopreventive properties to five distinct pathways: cell cycle progression, scavenging of reactive oxygen- or nitrogen-derived metabolites, TNF-α/TGF-ss signaling, WNT/β-catenin signaling and antibacterial properties. Therefore, in addition to their overall anti-inflammatory activity on the intestinal mucosa, 5-ASA compounds have specific effects on colorectal carcinogenesis at the molecular level. In 2005, a landmark meta-analysis of observational studies found a protective association between 5-ASA and CRC or a combined end point of CRC/dysplasia in UC patients. More recently, a meta-analysis failed to identify a protective effect of 5-ASA on CRC risk in non-referral populations, but in a separate analysis of 9 clinic-based studies, the pooled odds ratio was 0.58 (95% confidence interval: 0.45-0.75), further highlighting the chemopreventive effect of 5-ASA on CRC risk. In conclusion, 5-ASA therapy may reduce CRC risk by healing the mucosa of UC patients and via specific mechanisms of action at the molecular level. Conducting a clinical trial providing the best level of evidence by comparing UC patients receiving 5-ASA treatment versus those included in a placebo arm would be unethical.

Mechanisms of action of non-steroidal anti-inflammatory drugs (NSAIDs) and mesalazine in the chemoprevention of colorectal cancer

Colorectal cancer (CRC) is the third most common malignant neoplasm worldwide. Although conclusive evidence is still lacking, epidemiologic studies suggest that long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) has chemopreventive properties against CRC. Similarly, regular consumption of mesalazine, a drug structurally related to NSAIDs, seems to reduce the risk of CRC in patients with ulcerative colitis. These observations are supported by a large body of experimental data showing the ability of such drugs to inhibit multiple pathways that sustain colon carcinogenesis. This review summarizes the current information on the molecular mechanisms by which NSAIDs and mesalazine could interfere with CRC cell growth and survival.

Mechanisms of action of non-steroidal anti-inflammatory drugs (NSAIDs) and mesalazine in the chemoprevention of colorectal cancer

Colorectal cancer (CRC) is the third most common malignant neoplasm worldwide. Although conclusive evidence is still lacking, epidemiologic studies suggest that long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) has chemopreventive properties against CRC. Similarly, regular consumption of mesalazine, a drug structurally related to NSAIDs, seems to reduce the risk of CRC in patients with ulcerative colitis. These observations are supported by a large body of experimental data showing the ability of such drugs to inhibit multiple pathways that sustain colon carcinogenesis. This review summarizes the current information on the molecular mechanisms by which NSAIDs and mesalazine could interfere with CRC cell growth and survival.

Relationship between non-adherence to aminosalicylate medication and the risk of clinical relapse among Japanese patients with ulcerative colitis in clinical remission: a prospective cohort study

BACKGROUND

Thirty to forty-five percent of ulcerative colitis (UC) patients show non-adherence to aminosalicylates, and non-adherence has been reported to increase the risk of clinical relapse. Because Japan differs from Western countries in terms of health care and drugs administered, adherence to aminosalicylates in Japan may differ from that elsewhere. Therefore, we examined aminosalicylate adherence and its relationship to the risk of clinical relapse of UC in Japan.

METHODS

A 1-year, prospective cohort study was conducted in 104 outpatients with UC in remission who had taken aminosalicylates >6 months. Aminosalicylate adherence was evaluated using data from a self-administered questionnaire and medical records. Non-adherence was defined as taking <80 % of the prescribed dose of aminosalicylates. The primary outcome was the record of clinical relapse in medical charts.

RESULTS

Twenty-nine patients (27.9 %) were evaluated as showing non-adherence. Among all subjects, 24 patients (23.1 %) relapsed. The non-adherence group had a higher rate of 1-year relapse than did the adherence group (41.3 vs. 16.0 %). Multiple Cox regression analysis showed that non-adherence increased the risk of clinical relapse 2.3-fold (hazard ratio 2.3, 95 % confidence interval 1.004-5.24, p = 0.04).

CONCLUSIONS

Although the adherence rate in this study was slightly higher than that in previous studies, Japanese patients with UC who were not adherent to their medications had a twofold greater risk of relapse than those who were. These results indicate the importance of early identification of patients with non-adherence. A program to support medication taking behavior is needed to prevent UC relapse.

The 5-aminosalicylic acid antineoplastic effect in the intestine is mediated by PPARγ

Epidemiological evidences suggested that 5-aminosalicylic acid (5-ASA) therapy may prevent the development of colorectal cancer in inflammatory bowel disease patients. Our aim is to investigate whether peroxisome proliferator-activated receptor-γ (PPARγ) mediates the antineoplastic effects of 5-ASA. HT-29 and Caco-2 cells were treated by 5-ASA, rosiglitazone (PPARγ ligand) or etoposide (anticarcinogenic drug). Epithelial cell growth, proliferation and apoptosis were assessed by cell count, Ki-67 staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, respectively. The antineoplastic effect of 5-ASA was evaluated in a xenograft tumor model in SCID mice and in azoxymethane (AOM)-induced colon carcinogenesis in A/JOlaHsd mice. The role of PPARγ was examined by administration of PPARγ antagonist, GW9662 and in PPAR knockdown cells. Compared with untreated cells, treatment of HT-29 cells by 5-ASA inhibited significantly cell growth and cell proliferation (respectively, 60% and 63%) and induced apoptosis in 75% of cells. These effects were abolished by co-treatment with GW9662 and blunted in PPAR knockdown cells. Contrarily to etoposide, similar inhibitory effects of GW9662 were obtained in HT-29 cells treated with rosiglitazone. In the xenograft model, GW9662 abolished the therapeutic effect of 5-ASA, which decreased tumor weight and volume by 80% in SCID mice compared with untreated mice. In A/JOlaHsd mice, 5-ASA suppressed colon carcinogenesis by decreasing the number of aberrant crypt foci (75%) and aberrant crypts (22%) induced by AOM treatment with an absence of 5-ASA response after GW9662 administration. In conclusion, 5-ASA exerts potent antineoplastic effects that are mediated through PPARγ. These data provide new rational for designing more effective and safe antineoplastic PPARγ ligands with topical effects.

Survival after inflammatory bowel disease-associated colorectal cancer in the Colon Cancer Family Registry

AIM: To investigate the survival of individuals with colorectal cancer (CRC) with inflammatory bowel disease (IBD-associated CRC) compared to that of individuals without IBD diagnosed with CRC.

METHODS: Epidemiologic, clinical, and follow-up data were obtained from the Colon Cancer Family Registry (Colon CFR). IBD-associated cases were identified from self-report of physician diagnosis. For a subset of participants, medical records were examined to confirm self-report of IBD. Cox proportional hazards regression was applied to estimate adjusted hazard ratios (aHR) and 95%CI of mortality, comparing IBD-associated to non-IBD-associated CRC, adjusted for age at CRC diagnosis, sex, Colon CFR phase, and number of prior endoscopies. Following imputation to complete CRC stage information, adjustment for CRC stage was examined.

RESULTS: A total of 7202 CRC cases, including 250 cases of IBD-associated CRC, were analyzed. Over a twelve year follow-up period following CRC diagnosis, 2013 and 74 deaths occurred among non-IBD associated CRC and IBD-associated CRC patients, respectively. The difference in survival between IBD-associated and non-IBD CRC cases was not statistically significant (aHR = 1.08; 95%CI: 0.85-1.36). However, the assumption of proportional hazards necessary for valid inference from Cox regression was not met over the entire follow-up period, and we therefore limited analyses to within five years after CRC diagnosis when the assumption of proportional hazards was met. Over this period, there was evidence of worse prognosis for IBD-associated CRC (aHR = 1.36; 95%CI: 1.05-1.76). Results were similar when adjusted for CRC stage, or restricted to IBD confirmed in medical records.

CONCLUSION: These results support the hypothesis that IBD-associated CRC has a worse prognosis than non-IBD-associated CRC.

Clinicopathological features of ulcerative colitis-associated colorectal cancer pointing to efficiency of surveillance colonoscopy in a large retrospective Japanese cohort

PURPOSE

Cancer surveillance has been conducted in patients with ulcerative colitis (UC), and the number of operative cases of ulcerative colitis-associated colorectal cancer (UC-CRC) has been increasing. The aim of this study was to clarify the clinicopathological features and prognoses of UC-CRC patients and the relationship between surveillance colonoscopy and UC-CRC.

METHODS

The clinical records of 1,274 UC patients who required surgery between 1984 and 2010 at a single institution were reviewed retrospectively. Of these, 83 patients had CRC (107 sections). All cases were extracted from the database, along with their clinicopathological data.

RESULTS

The 5-year survival rate of the UC-CRC group was 89 %. The 5-year survival rate was 100 % in stages 0 and II, 96 % in stage I, 56 % in stage III, and 0 % in stage IV. Surveillance colonoscopy was performed for 40 of the 83 patients. Of 40 patients, 30 with UC who underwent surveillance colonoscopies and 22 of 43 patients without surveillance colonoscopies were in stages 0 to I (P = 0.04).

CONCLUSION

The number of UC-CRC patients who are diagnosed by surveillance colonoscopy is increasing, and many of them are detected in the very early stages (stages 0 or I). Thus, the survival rate of UC-CRC is better than before. Surveillance colonoscopy proofs efficient as CRC are detected in earlier stages.

Dysplasia and colorectal cancer in a patient with ulcerative colitis and primary sclerosing cholangitis: a case report and a short review of the literature

Primary sclerosing cholangitis is a chronic progressive disorder which involves the medium size and large ducts in the intrahepatic and extrahepatic biliary tree. The great majority of cases have underlying inflammatory bowel disease, mainly ulcerative colitis. A higher risk of colorectal cancer has been described among ulcerative colitis patients with primary sclerosing cholangitis. Here we report a case of a primary sclerosing cholangitis in a young male with a newly diagnosed ulcerative colitis presenting with colonic dysplasia. Surveillance for colorectal cancer should be strongly recommended in this group of patients.

Is treatment with 6-mercaptopurine for colitis associated with the development of colorectal cancer?

BACKGROUND

Patients with ulcerative colitis and Crohn's colitis have an increased risk of colon cancer influenced by the duration, extent, and severity of disease. Surveillance colonoscopy serves to detect cancer and precancerous dysplasia at the earliest possible time. Reduction of inflammation should theoretically reduce the development of cancer. Immunosuppressives should do so, but there is a fear that indeed the risk of cancer might be increased with their use. Our study was conducted to determine whether a relationship exists between receiving treatment with 6-MP for ulcerative and Crohn's colitis and increasing or decreasing the incidence of colorectal cancer (CRC).

METHODS

We conducted a single-center, retrospective cohort study of patients with long standing colitis (ulcerative and Crohn's) using the database of the senior investigator (B.I.K.). Two groups were matched based on their propensity to receive treatment with 6-MP; one group received 6-MP treatment, the other did not. Both groups were compared on the incidence of colon cancer.

RESULTS

No significant differences existed between the two cohorts with regard to type of disease, duration, extent, age, and sex. Six out of 27 patients not on 6-MP and seven out of 27 patients on 6-MP developed CRC (P= 1).

CONCLUSIONS

We conclude that there is neither sufficient evidence currently to state that 6-MP is associated with an increased development of CRC, nor that it has a chemopreventive effect.

Differential response of flat and polypoid colitis-associated colorectal neoplasias to chemopreventive agents and heterocyclic amines

Individuals with ulcerative colitis face an increased risk of developing colorectal cancer and would benefit from early chemopreventive intervention. Results from preclinical studies in the mouse model of dextran sulfate sodium-induced colitis demonstrate that flat and polypoid colitis-associated dysplasias arise via distinct genetic pathways, impacted by the allelic status of p53. Furthermore, flat and polypoid dysplasias vary in their response to induction by the heterocyclic amine 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and inhibition by 5-aminosalicylic acid, a common therapy for the maintenance of colitis patients. These data suggest that use of combination therapy is essential for the optimal inhibition of colitis-associated colorectal cancer.

Usefulness of salicylate and thiopurine coprescription in steroid-dependent ulcerative colitis and withdrawal strategies

5-aminosalicylic acid (5-ASA) and thiopurines (azathioprine and mercaptopurine) are the most common drugs used as a maintenance treatment for ulcerative colitis. A considerable proportion of these patients develop corticosteroid dependency, and thiopurines are the standard treatment in this scenario. Dual prescriptions of both thiopurines and 5-ASA are common practice in steroid-dependent ulcerative colitis, in an attempt to optimize the efficacy of therapy. On the one hand, the potential protective role of 5-ASA against colorectal cancer argues in favour of prescription of both medications. The possible synergism between the two drugs, because of the inhibition of thiopurine methyltransferase (TPMT) enzyme activity by 5-ASA, has been postulated as another justification for dual prescription. However, existing evidence does not support that this combined strategy is superior to monotherapy with thiopurines. On the other hand, in patients showing prolonged disease remission, the possibility of discontinuing maintenance treatment can be considered on an individualized basis. The high frequency of relapses after thiopurine withdrawal should always be taken into account, but the potential adverse effects of the medication also need to be considered. A properly indicated treatment with thiopurines may need to be continued for life in many patients.

Higher apoptosis index and proliferation index in colonocytes of patients with ulcerative colitis in remission

Ulcerative colitis (UC) is a inflammatory disease of large bowel. The amount of people suffering from UC increases from year to year. Pathogenesis of this affection is still not entirely clear. Mechanisms of proliferation and apoptosis in colonocytes in the course of the disease are defected.

THE AIM OF THE STUDY

was to assess the rate of proliferation and intensity of apoptosis in colonocytes in patients with diagnose UC.

MATERIAL AND METHODS

Colon pathological samples taken from patients with diagnosed ulceraive colitis were examined. Patients were in both clinical and endoscopic remission and were treated with mesalazin. They were patient of Department of General and Colorectal Surgery. To estimate proliferation index dye with monoclonal antibody against Ki67. To determine apoptosis level immunohistochemistry with antybody against Bax was used.

RESULTS

Average Ki-67 in the test group was 42,13%, the largest value amounted to 57% and the lowest of 33%. Average value of Bax was 1.47 and ranged between 0-3. High index of bax appear not only in the bottom of the crypt, but also at their outlet.

CONCLUSIONS

In ulecerative colitis genetic and immunological disturbances occur despite treatment. Mesalazine acting only on certain routes associated with the UC holds the remission, without, however "the molecular remission". Thus, it appears that the results of our research are another proof of the necessary caution in weaning support treatment.

The role of chemoprevention of colorectal cancer with 5-aminosalicylates in ulcerative colitis

5-aminosalicylates (5-ASA) are widely used to treat patients with ulcerative colitis. Experimental data suggest that these agents can potentially be used in a chemopreventive fashion to inhibit the development of colitis-associated colorectal cancer (CRC); however, observational studies investigating a possible risk reduction of CRC by 5-ASA therapy have revealed conflicting results. Currently, it appears that 5-ASA have no or only a very limited effect as a deterrence against CRC. Thus, a general recommendation for long-term use of 5-ASA solely for chemopreventive measures is not warranted.

The role of anti-inflammatory drugs in colorectal cancer

A large body of evidence indicates that genetic mutations, epigenetic changes, chronic inflammation, diet, and lifestyle are key risk factors for colorectal cancer (CRC). Prevention of CRC has long been considered a plausible approach for the population and individuals at high risk for developing this disease. A significant effort has been made in the development of novel drugs for both prevention and treatment over the past two decades. This review highlights recent advances in our understanding of the role of nonsteroidal anti-inflammatory drugs in CRC prevention and adjuvant treatment. Moreover, we focus on the molecular mechanisms underlying the antitumor effects of these drugs in CRC. The knowledge of how anti-inflammatory agents inhibit cancer formation and progression may provide a rationale for the development of more effective chemopreventive and chemotherapeutic agents with less toxicity.

Potential avenues for immunotherapy of colitis-associated neoplasia

In patients with inflammatory bowel disease, chronic intestinal inflammation severely increases the risk for cancer development. In fact, various aspects of inflammation such as oxidative stress, cyclooxygenases and proinflammatory cytokines have been shown to support many aspects of cancer growth. During recent years, various experimental studies have increased our understanding of the molecular mechanisms leading to colitis-associated cancer. In particular, cytokines such as TNF-α or IL-6, which are involved in the pathogenesis of inflammation and cancer development, could be promising targets for the molecular prevention of colitis-associated cancer.