Chemoprophylaxis of colorectal cancer in inflammatory bowel disease: current concepts

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.

Use of thiopurines and risk of colorectal neoplasia in patients with inflammatory bowel diseases: a meta-analysis

OBJECTIVE

Inflammatory bowel disease (IBD) is commonly treated with thiopurines such as azathioprine and mercaptopurine for the maintenance of remission. Studies examining chemopreventive of these medications on colorectal neoplasm in IBD patients have yielded conflicting results. We performed a meta-analysis to assess the role of thiopurines for this indication.

METHODS

We performed a systematic search of PubMed, Web of Science, EMBASE and Cochrane to identify studies reporting colorectal neoplasm from IBD patients treated with thiopurines and conducted a meta-analysis of pooled relative risk (RR) using the random effects model.

RESULTS

Nine case-control and ten cohort studies fulfilled the inclusion criteria. The use of thiopurines was associated with a statistically significant decreased incidence of colorectal neoplasm (summary RR=0.71, 95% CI=0.54-0.94, p=0.017), even after adjustment for duration and extent of the disease, but there was high heterogeneity among studies (I(2)=68.0%, p<0.001). The RR of advanced neoplasm (high-grade dysplasia and cancer) was 0.72 (95%CI=0.50-1.03, p=0.070) and that of cancer was 0.70 (95% CI=0.46-1.09, p=0.111) for thiopurine-treated patients. Heterogeneity of the studies was affected by the sample size (

CONCLUSION

The current meta-analysis revealed that thiopurines had a chemopreventive effect of colorectal neoplasms and a tendency of reducing advanced colorectal neoplasms in IBD. Due to the heterogeneity of included studies, these results should be interpreted with caution.

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MESH Headings

• Azathioprine/adverse effects
• Azathioprine/therapeutic use
• Colorectal Neoplasms/chemically induced
• Humans
• Inflammatory Bowel Diseases/drug therapy
• Mercaptopurine/adverse effects
• Mercaptopurine/therapeutic use
• Risk

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Affiliation(s)

Jianfeng Gong Department of General Surgery, Jinling hospital, Medical School of Nanjing University, Nanjing, PR China
Lijing Zhu Department of Oncology, Drum Tower hospital, Medical school of Nanjing University, Nanjing, PR China
Zhen Guo Department of General Surgery, Jinling hospital, Medical School of Nanjing University, Nanjing, PR China
Yi Li Department of General Surgery, Jinling hospital, Medical School of Nanjing University, Nanjing, PR China
Weiming Zhu Department of General Surgery, Jinling hospital, Medical School of Nanjing University, Nanjing, PR China
Ning Li Department of General Surgery, Jinling hospital, Medical School of Nanjing University, Nanjing, PR China
Jieshou Li Department of General Surgery, Jinling hospital, Medical School of Nanjing University, Nanjing, PR China

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Thiopurines related malignancies in inflammatory bowel disease: Local experience in Granada, Spain

AIM: To investigate the incidence of neoplasms in inflammatory bowel disease (IBD) patients and the potential causative role of thiopurines.

METHODS: We performed an observational descriptive study comparing the incidence of malignancies in IBD patients treated with thiopurines and patients not treated with these drugs. We included 812 patients which were divided in two groups depending on whether they have received thiopurines or not. We have studied basal characteristics of both groups (age when the disease was diagnosed, sex, type of IBD, etc.) and treatments received (Azathioprine, mercaptopurine, infliximab, adalimumab or other immunomodulators), as well as neoplasms incidence. Univariate analysis was performed with the student t test, χ² test or Wilcoxon exact test as appropriate. A logistic regression analysis was performed as multivariate analysis. Statistical significance was establish at P values of less than 0.05, and 95%CI were used for the odds ratios.

RESULTS: Among 812 patients included, 429 (52.83%) have received thiopurines: 79.5% azathioprine, 14% mercaptopurine and 6.5% both drugs. 44.76% of patients treated with thiopurines and 46, 48% of patients who did not receive this treatment were women (P > 0.05). The proportion of ulcerative colitis patients treated with thiopurines was 30.3% compare to 66. 67% of patients not treated (P < 0.001). Mean azathioprine dose was 123.79 ± 36.5 mg/d (range: 50-250 mg/d), mean usage time was 72.16 ± 55.7 mo (range: 1-300 mo) and the accumulated dose along this time was 274.32 ± 233.5 g (1.5-1350 g). With respect to mercaptopurine, mean dose was 74.7 ± 23.9 mg/d (range: 25-150 mg/d), mean usage time of 23.37 ± 27.6 mo (range: 1-118 mo), and the accumulated dose along this time was 52.2 ± 63.5 g (range: 1.5-243 g). Thiopurine S-methyltransferase activity was tested in 66% of patients treated with thiopurines, among which 98.2% had an intermediate or high activity. Among the patients treated with thiopurines, 27.27% (112 patients) and 11.66% (50 patients) received treatment with Infliximab and Adalimumab respectively, but only 1.83% (7 patients) and 0.78% (3 patients) received these drugs in the group of patients who did not received thiopurines (P < 0.001 and P < 0.001 respectively). Finally, 6.8% (29 patients) among those treated with thiopurines have received other immunesupresants (Methotrexate, Tacrolimus, Cyclosporin), compare to 1% (4 patients) of patients not treated with thiopurines (P < 0.001). Among patients treated with thiopurines, 3.97% developed a malignancy, and among those not treated neoplasms presented in 8.1% (P = 0.013). The most frequent neoplasms were colorectal ones (12 cases in patients not treated with thiopurines but none in treated, P < 0.001) followed by non-melanoma skin cancer (8 patients in treated with thiopurines and 6 in not treated, P > 0.05).

CONCLUSION: In our experience, thiopurine therapy did not increase malignancies development in IBD patients, and was an efective and safe treatment for these diseases.

Indian Society of Gastroenterology consensus on ulcerative colitis

In 2010, the Indian Society of Gastroenterology's Task Force on Inflammatory Bowel Diseases undertook an exercise to produce consensus statements on ulcerative colitis. This consensus, produced through a modified Delphi process, reflects our current understanding of the definition, diagnostic work up, treatment and complications of ulcerative colitis. The consensus statements are intended to serve as a reference point for teaching, clinical practice, and research in India.

Preclinical cancer chemoprevention studies using animal model of inflammation-associated colorectal carcinogenesis

Inflammation is involved in all stages of carcinogenesis. Inflammatory bowel disease, such as ulcerative colitis and Crohn’s disease is a longstanding inflammatory disease of intestine with increased risk for colorectal cancer (CRC). Several molecular events involved in chronic inflammatory process are reported to contribute to multi-step carcinogenesis of CRC in the inflamed colon. They include over-production of free radicals, reactive oxygen and nitrogen species, up-regulation of inflammatory enzymes in arachidonic acid biosynthesis pathway, up-regulation of certain cytokines, and intestinal immune system dysfunction. In this article, firstly I briefly introduce our experimental animal models where colorectal neoplasms rapidly develop in the inflamed colorectum. Secondary, data on preclinical cancer chemoprevention studies of inflammation-associated colon carcinogenesis by morin, bezafibrate, and valproic acid, using this novel inflammation-related colorectal carcinogenesis model is described.

Pros and cons of medical management of ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory disease characterized by diffuse mucosal inflammation limited to the colon and rectum. Although a complete medical cure may not be possible, UC can be treated with medications that induce and maintain remission. The medical management of this disease continues to evolve with a goal to avoid colectomy and ultimately alter the natural history of UC. Emergence of antitumor necrosis factor-α (TNF-α) agents has expanded the medical armamentarium. 5-Aminosalicylates continue to be used in mild to moderate UC and corticosteroids are mainly used for induction of remission with immunomodulators (6-mercaptopurine/azathiopurine/methotrexate) being applied as steroid-sparing agents for maintenance therapy. Infliximab has been approved by the U.S. Food and Drug Administration and used in the treatment of moderate to severe UC; nevertheless, its use may be associated with significant adverse effects and have a negative impact on the postoperative course should the patients undergo restorative proctocolectomy. In addition, there is always a concern about patients' compliance to medical therapy, cost of medications, and risk for UC-associated dysplasia. The authors discuss the pros and cons of medications used in the treatment of UC.

Review article: malignancy on thiopurine treatment with special reference to inflammatory bowel disease

BACKGROUND

Immunosuppression is a risk factor for carcinogenesis. Thiopurines specifically contribute to this. As thiopurines are used more aggressively in the treatment of IBD, it is likely that we will see more thiopurine-related malignancy.

AIM

To review the literature, exploring how immunosuppression, thiopurines specifically, might cause cancer and which malignancies occur in practice, placing specific emphasis on IBD cohorts.

METHODS

Search terms included 'malignancy' 'cancer' 'azathioprine' 'mercaptopurine' 'tioguanine (thioguanine)' 'thiopurine' and 'inflammatory bowel disease' 'Crohn's disease' 'ulcerative colitis'. We also searched for specific cancers (lymphoma, colorectal cancer, skin cancer, cervical cancer) and reviewed the reference lists of the articles detected.

RESULTS

Immunosuppression is associated with an increased risk of cancer. Thiopurines are associated with specific additional risks. In IBD cohorts, very few thiopurine-related malignancies have been reported. However, studies suggest a relative risk of 4-5 for lymphoma. This still translates into a low actual risk, (one extra lymphoma in every 300-1400 years of thiopurine treatment).

CONCLUSIONS

Whilst we must be aware of this risk and counsel our patients appropriately, thiopurines remain a mainstay of IBD therapy. We present practical advice aimed at minimizing our patients' risk of developing malignancy, whilst optimizing the benefits that thiopurines can provide.

Oral administration of the anti-proliferative substance taurolidine has no impact on dextran sulfate sodium induced colitis-associated carcinogenesis in mice

Background:

New chemopreventive strategies for ulcerative colitis (UC)-associated dysplasia and cancer have to be evaluated. Taurolidine (TRD) has anti-inflammatory, anti-proliferative and anti-neoplastic properties with almost absent toxicity. The aim of the study was to determine whether TRD decreases dysplasia in the well-characterized Dextran Sulfate Sodium – Azoxymethane (DSS-AOM) animal model for UC-associated carcinogenesis.

Material and Methods:

The DSS-AOM model of carcinogenesis was induced in female inbred C57BL/6 mice. Half of the mice were treated with TRD, the other served as control. After 100 days macroscopic, histological and immunhistochemical (β-Catenin, E-Cadherin, SOX9, Ki-67, Cyclin-D1) examination of the colon was performed.

Results:

Incidence, multiplicity, grading and growth pattern of adenomas did not differ significantly between TRD and control group. In all animals, inflammatory changes were absent. Immunhistochemistry revealed increased expression of Ki-67, β-catenin, SOX9 and Cyclin-D1 in adenomas compared to normal mucosa – without significant difference between TRD and control treatment.

Conclusion:

Oral administration of TRD has no impact on DSS-induced colitis-associated carcinogenesis. However, SOX9 and Cyclin-D1 representing key members of the Wnt pathway have not yet been described in the DSS-AOM model of carcinogenesis – underlining the importance of this oncogenic pathway in this setting.

Injecting drugs by a tube from appendix stump to colon may be a good method for dealing with refractory ulcerative colitis

Ulcerative colitis is a kind of nontransmural chronic inflammatory bowel disease which mainly affects colon and rectum, it has a classic character of the relapsing and remitting course. The main symptoms of ulcerative colitis are intermittent bloody diarrhea, rectal urgency, and tenesmus. As a chronic disease, it can disable and disrupt the daily life of patients. The main treatments for ulcerative colitis are medical management and surgical management, but the drugs used by traditional way have many severe side effects and invalid for refractory ulcerative, and traditional surgery has many complications, so we propose a new treatment of ulcerative colitis, which is the combination of drugs and a little surgery-appendectomy: injecting drugs by a tube from appendix stump to colon after appendectomy by laparoscope, this treatment can decrease the side effects of oral drugs and increase the drug levels as topical managements. Our hypotheses might be an effect way to deal with refractory ulcerative colitis especially total or upper ulcerative colitis, and it is a treatment with little wound and few complications.

Diagnosis and management of dysplasia in patients with ulcerative colitis and Crohn's disease of the colon

To minimize the possibility of developing lethal colorectal cancer (CRC) in ulcerative colitis (UC) and Crohn's colitis, patients are usually enrolled in a program of dysplasia surveillance. The success of a surveillance program depends on the identification of patients with dysplasia and timely referral for colectomy. While a number of issues might stand in the way of a surveillance system achieving its maximal effect (less than ideal agreement in the interpretation of biopsy specimens, sampling error by endoscopists, delays in referral to surgery, and patient drop-out among others), circumstantial evidence supports the concept that colonoscopic dysplasia surveillance is an effective means of reducing CRC mortality and morbidity while minimizing the application of colectomy for cancer prevention. This review critically appraises key issues in the diagnosis and management of dysplasia in UC and Crohn's disease as well as adjunct efforts to prevent CRC in inflammatory bowel disease.

Ulcerative colitis: current medical therapy and strategies for improving medication adherence

Ulcerative colitis (UC) is chronic inflammation of large intestine and often requires lifelong medication. Medical therapy aims to induce and maintain a clinical remission, reduce the risk of colorectal cancer and improve quality of life. Aminosalicylates are currently the first choice therapy both for the induction and the maintenance of remission in the patients with mild-to-moderate UC. For moderate-to-severe cases or those who do not respond to aminosalicylate therapy, additional treatment options including corticosteroids, immunomodulators, biological agents, cyclosporin, tacrolimus and surgery are available. Poor adherence to medication has been an important barrier to successful management of UC. Nonadherence has been associated with increased relapse rates, higher risk of colorectal cancer, poor quality of life and significantly increased healthcare costs. Therefore, improving adherence to medication is an important approach for a better care of the patients with UC. Definitive strategies are required to help the patients effectively self manage their disease and improve adherence. This review examines current medical therapy for UC, research progresses on medication adherence and the possible strategies for improving adherence in these patients.