Jens Nederby Nielsen

Thymidylate Synthase and Methylenetetrahydrofolate Reductase Gene Polymorphism in Normal Tissue As Predictors of Fluorouracil Sensitivity

PURPOSE To analyze thymidylate synthase (TS) and methylenetetrahydrofolate reductase (MTHFR) gene polymorphism with respect to fluorouracil (FU) sensitivity. PATIENTS AND METHODS The study included a retrospective analysis of 88 patients with metastatic colorectal cancer and a prospective trial with 51 patients also with measurable metastases. All patients were treated with FU and leucovorin. The analysis of gene polymorphism was performed on normal intestinal tissue and lymphocytes. RESULTS The response rate was significantly higher in patients with TS 3R/3R or MTHFR 677 TT gene polymorphism compared with the other groups. The difference of response rate translated to a difference in time to progression. Similar results were observed in the retrospective analysis and the prospective confirmatory trial. CONCLUSION The analysis of gene polymorphism allows delineation of a group of patients (30%) with a response rate to a single drug of approximately 50%. This information should be used in the design of tailored treatment.

Platelets and anticoagulant capacity in patients with inflammatory bowel disease.

Patients with inflammatory bowel disease (IBD) are susceptible to thromboembolic complications. Several mechanisms can be responsible, including abnormal regulation of coagulation activity, disturbances of fibrinolysis, inflammatory reactions and thrombocytosis. The aim of this study was to assess hemostatic alterations in these parameters during exacerbation of disease. We studied disease activity in 99 IBD patients receiving anti-inflammatory therapy, in relation to: procoagulant markers, i.e. prothrombin fragment F1 + 2 (F1 + 2), D-dimer and platelet count, anticoagulant markers, i.e. protein C, protein S and antithrombin, and a mediator of inflammation (IL-6). Coagulation activity and platelet count were increased during active disease in IBD patients compared with those in a state of remission. The IL-6 concentrations were positively correlated with disease activity and thrombocytosis in patients with ulcerative colitis, but no association with the anticoagulant capacity could be demonstrated except for a decrease in protein C during high disease activity.

Omega-3 fatty acids inhibit an increase of proinflammatory cytokines in patients with active Crohn's disease compared with omega-6 fatty acids

Background : Crohns disease is a chronic inflammatory condition affecting the gastrointestinal tract. Polyunsaturated omega‐3 fatty acids given orally may reduce the secretion of proinflammatory cytokines and hereby downregulate the inflammatory process.

Serum Trefoil Factors in Patients with Inflammatory Bowel Disease

Background: Trefoil factors (TFF1–3) play a critical role in mucosal protection and repair in the gastrointestinal tract. The aims of the present study were to examine associations between serum TFF1–3 and clinical and biochemical markers reflecting disease activity and to examine changes in TFF1–3 in patients with inflammatory bowel disease (IBD) before and during high-dose prednisolone treatment and tapering.Methods: Serum concentrations of TFF1–3 were quantified in 48 ulcerative colitis (UC) and 50 Crohn’s disease (CD) patients with little or moderate activity. Additionally, serum TFF concentrations were determined in patients with severe activity in colon IBD (4 UC and 6 CD) before and during prednisolone treatment with 7 healthy subjects as controls. Results: Median concentrations of TFF1, TFF2, and TFF3 were significantly increased in IBD patients compared with healthy controls (p < 0.01). TFF3 concentrations correlated with clinical and biochemical parameters of disease activity in UC patients. In addition, a trend towards reduction in TFF concentrations during treatment with prednisolone and concomitant clinical and biochemical remission was observed. Conclusions: The present data support the concept that trefoil peptides are upregulated and may play a role in IBD mucosal protection and repair. In UC patients, TFF3 levels were increased in active disease levels correlated with disease activity indices. Due to a large variation, serum TFFs are not a potential marker for disease activity.

Epidermal growth factor (EGF) A61G polymorphism and EGF gene expression in normal colon tissue from patients with colorectal cancer

Introduction. EGF/EGFR interactions are important mechanisms behind colorectal tumour development and growth. Recently a single nucleotide polymorphism in the EGF gene has been identified (EGF A61G). It may be a potential predictor for survival of patients receiving EGFR-inhibitor cetuximab treatment, but the clinical importance and the functional influence on EGF gene expression levels in colorectal cancer (CRC) patients have not yet been further assessed. The aim of the present study was to investigate the relationship between EGF A61G genotype and EGF gene expression levels in colorectal adenocarcinomas and normal colon tissue. Material and methods. Eighty-one CRC patients were included in the study. Tissue samples from normal colon, adenocacinomas and corresponding blood samples were analysed by real-time PCR for EGF gene expression and EGF A61G genotype, respectively. Results. Thirty-three percent were AA, 48% and 19% A/G and G/G respectively. We found a significantly lower median age in the A/A group compared to the G/G group, suggesting a later time of diagnosis in the G/G patients. There was a significant difference between the median EGF gene expression among the three genotypes in normal colon (p < 0.001) but not in adenocarcinomas. Furthermore, the median EGF gene expression was lower in CRC tissue than in normal colon samples, (0.13 (range 0.01–6.4) vs. 0.76, (range 0.013–5.55)). Conclusion. We suggest that EGF A61G genotype has a functional influence on EGF gene expression in normal colon in CRC patients. The clinical implications warrant further investigations in prospective trials.

Saliva Interleukin-6 in patients with inflammatory bowel disease

Objective. The inflammatory bowel diseases (IBD), Crohns disease (CD) and ulcerative colitis (UC) are chronic inflammatory conditions that affect the gastrointestinal tract. In regulation of this inflammatory process, Interleukin-6 (IL-6) has a major role. Overproduction of IL-6 by immunocompetent cells contributes to development of the inflammatory condition. Elevated levels of IL-6 in saliva could be expected, because the saliva-producing cells are part of the digestive system. Material and methods. IL-6 concentrations in saliva and plasma were studied in patients with CD (n=15), UC (n=7) and reference persons (RP) (n=19) by use of an ELISA method. Results. A significant difference in saliva IL-6 concentration between CD patients (median 16.9 ng/L; p<0.05) and RP (median 6.3 ng/L) was found. A significant difference in plasma IL-6 concentration between CD (median 10.3 ng/L; p<0.001) or UC (median 7.8 ng/L; p<0.001) and RP (median 0.8 ng/L) was observed. In patients with CD, plasma IL-6 correlated significantly with C-reactive protein (CRP) as well as albumin. In patients with UC, saliva IL-6 and plasma IL-6 correlated significantly with AI (activity index) scores as well as albumin. In patients with UC, a significant correlation between the saliva and plasma IL-6 concentrations was found. Conclusions. IL-6 was found in saliva in patients with IBD, documenting the general involvement of the gastrointestinal tract extending to the mouth cavity, and measuring IL-6 may be an additional method for evaluating and monitoring the disease activity.

Insulin-like growth factors (IGFs) and IGF binding proteins in active Crohn's disease treated with ω-3 or ω-6 fatty acids and corticosteroids

Objective. Catabolism and growth impairment are well-known complications of inflammatory bowel disease (IBD). This may be caused by the disease activity itself and/or the medical treatment, and both may lead to changes in the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis. The aim of the present study was to examine the effects of enteral nutrition, Impact Powder®, as adjuvant therapy to corticosteroid treatment on changes in the GH/IGF-I axis in patients with Crohns disease (CD). Material and methods. The patients were randomized to 3-IP (ω-3-fatty acid (FA), 3 g/day) or 6-IP (ω-6-FA, 9 g/day). Changes in total IGF-I (tIGF-I) and total IGF-II (tIGF-II), free IGF-I (fIGF-I), IGF binding proteins (IGFBP-1 and IGFBP-3), IGFBP-3 protease activity and insulin levels were examined in 31 patients with active CD (CDAI: 186–603) during treatment with prednisolone (40 mg for 1 week) and tapering the dose by 5 mg/week. Clinical and biochemical markers of inflammation were studied at day 0, and after 5 and 9 weeks. Results. There were no differences at baseline between the two groups. During the treatment period, tIGF-I, fIGF-I and IGFBP-3 increased significantly in both groups compared to baseline (p<0.05) without differences between the groups. Insulin and IGFBP-1 showed no significant changes throughout the treatment period. Conclusions. There was no difference between 3-IP and 6-IP as adjuvant enteral nutrition on the GH/IGF-I axis. The changes observed in the GH/IGF-I axis are in line with previously published studies and may be explained by corticosteroid treatment; however, we cannot exclude an additional effect of ω3-/ω6 FA as adjuvant enteral nutrition.

Microsatellite Instability and the Association with Plasma Homocysteine and Thymidylate Synthase in Colorectal Cancer

The possible associations between microsatellite instability, homocysteine and thymidylate synthase were investigated in tumors and plasma from 130 patients with colorectal cancer. Other analyses included thymidylate synthase and 5,10-methylene-tetrahydrofolate reductase gene polymorphisms, carcinoembryonic antigen, vitamin B12, and folate. Microsatellite instability of tumors was associated with higher levels of plasma homocysteine (p = 0.008) and higher protein expression of thymidylate synthase (p < 0.001). Supplemental analyses ruled out that the finding could be explained by the other analyzed factors. CEA was not associated with neither homocysteine nor microsatellite instability. The data suggests that there is a more pronounced methyl unit deficiency in microsatellite instable tumors.

Impact of enteral supplements enriched with omega-3 fatty acids and/or omega-6 fatty acids, arginine and ribonucleic acid compounds on leptin levels and nutritional status in active Crohn's disease treated with prednisolone.

Background: Patients with Crohn’s disease (CD) often develop malnutrition due to disease activity. We aimed to assess the effect of two different enteral supplements of Impact® Powder (IP; Novartis, Switzerland) on leptin levels and nutritional status in active CD patients during prednisolone treatment and tapering. Methods: Thirty-one CD patients were randomized to IP Extra (group 1) or IP Standard (group 2). Leptin levels, nutritional, clinical and biochemical markers were studied at inclusion, after 5 and after 9 weeks of the study. Results: Leptin levels, body mass index (BMI) and total cholesterol increased significantly within both groups at week 5 compared to inclusion. Leptin levels correlated with BMI in both groups at inclusion and in group 2 at week 9. In group 1, triglyceride levels remained unchanged, while levels in group 2 increased significantly at week 5 compared to inclusion. Clinical and biochemical markers improved during the study compared to inclusion. Conclusions: Increased leptin levels during the study progress were transient, decreasing due to prednisolone withdrawal at the end of the study. Both formulas used as adjuvant therapy to prednisolone treatment were able to improve nutritional status in CD patients.

Low S-adenosylmethionine concentrations found in patients with severe inflammatory bowel disease.

Abstract Background: S-adenosylmethionine is a methyl donor in many cellular reactions including detoxification of constantly produced hydrogen sulphide in the colon. A reduced capacity to detoxify hydrogen sulphide may be implicated in the pathogenesis of inflammatory bowel disease. S-adenosylmethionine could be low if this assumption is correct. We compared S-adenosylmethionine concentrations in whole blood in patients with severe and moderate inflammatory bowel disease with healthy reference persons. Methods: S-adenosylmethionine concentrations in whole blood were measured using high-pressure liquid chromatography. Patients with Crohns disease (n=21), ulcerative colitis (n=7) and healthy age-matched reference persons (or controls) (n=17) were studied. Results: S-adenosylmethionine concentrations were significantly decreased in patients with severe inflammatory bowel disease (mean 1.10 mg/l) as compared to patients with moderate Crohns disease and ulcerative colitis (mean 1.83 mg/l) and reference persons (mean 1.84 mg/l). Statistically significant inverse correlations were found between S-adenosylmethionine concentration and activity index (p<0.01 and R2=0.86) as well as Crohns disease activity index (p<0.01 and R2=0.50) scores. Conclusions: Low concentrations of S-adenosylmethionine were found in patients with severe inflammatory bowel disease. Future studies will show whether S-adenosylmethionine is a marker for disease activity and a possible tool for investigation of sulphur toxicity as a causative mechanism in inflammatory bowel disease.