Resveratrol is a naturally occurring polyphenol with cancer chemopreventive properties. The objective of the current study was to investigate the effect of resveratrol on the human colonic adenocarcinoma cell line Caco-2. The compound inhibited cell growth and proliferation of Caco-2 cells in a dose-dependent manner (12.5-200 micromol/L) as assessed by crystal violet assay, [(3)H]thymidine and [(14)C]leucine incorporation. Furthermore, apoptosis was determined by measuring caspase-3 activity, which increased significantly after 24 and 48 h of treatment with 200 micromol/L resveratrol. Perturbed cell cycle progression from the S to G2 phase was observed for concentrations up to 50 micromol/L, whereas higher concentrations led to reversal of the S phase arrest. These effects were specific for resveratrol; they were not observed after incubation with the stilbene analogs stilbenemethanol and rhapontin. Levels of cyclin D1 and cyclin-dependent kinase (cdk) 4 proteins were decreased, as revealed by immunoblotting. In addition, resveratrol enhanced the expression of cyclin E and cyclin A. The protein levels of cdk2, cdk6 and proliferating cell nuclear antigen were unaffected. Similar results were obtained for the colon carcinoma cell line HCT-116, indicating that cell cycle inhibition by resveratrol is independent of cyclooxygenase inhibition. The phosphorylation state of the retinoblastoma protein in Caco-2 cells was shifted from hyperphosphorylated to hypophosphorylated at 200 micromol/L, which may account for reversal of the S phase block at concentrations exceeding 50 micromol/L. These findings suggest that resveratrol exerts chemopreventive effects on colonic cancer cells by inhibition of the cell cycle.

Piceatannol, a naturally occurring analog of resveratrol, was previously identified as the active ingredient in herbal preparations in folk medicine and as an inhibitor of p72(Syk). We studied the effects of piceatannol on growth, proliferation, differentiation and cell cycle distribution profile of the human colon carcinoma cell line Caco-2. Growth of Caco-2 and HCT-116 cells was analyzed by crystal violet assay, which demonstrated dose- and time-dependent decreases in cell numbers. Treatment of Caco-2 cells with piceatannol reduced proliferation rate. No effect on differentiation was observed. Determination of cell cycle distribution by flow cytometry revealed an accumulation of cells in the S phase. Immunoblotting demonstrated that cyclin-dependent kinases (cdk) 2 and 6, as well as cdc2 were expressed at steady-state levels, whereas cyclin D1, cyclin B1 and cdk 4 were downregulated. The abundance of p27(Kip1) was also reduced, whereas the protein level of cyclin E was enhanced. Cyclin A levels were enhanced only at concentrations up to 100 micromol/L. These changes also were observed in studies with HCT-116 cells. On the basis of our findings, piceatannol can be considered to be a promising chemopreventive or anticancer agent.

Mevastatin is an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol synthesis. Butyrate, a short-chain fatty acid, reduces proliferation and induces differentiation of human colon cancer cells. The aim of our study was to determine the effect of mevastatin, alone or in combination with butyrate, on proliferation, the cell cycle and apoptosis in the human colorectal carcinoma cell line Caco-2. In this report we show that mevastatin combined with butyrate synergistically suppressed growth of Caco-2 cells in a dose- and time-dependent manner. In addition, incubation with mevastatin arrested cells in the G1 phase of the cell cycle after 24 h with a switch to the G2/M phase after 72 h. This was accompanied by a down-regulation of cyclin-dependent kinases (cdk) 4 and cdk 6 as well as cyclin D1, while cdk 2 and cyclin E protein levels remained unchanged during mevastatin treatment. Cell cycle inhibitors p21 and p27 were significantly upregulated by mevastatin. The proapoptotic properties of mevastatin were further enhanced by co-incubation with butyrate. Lastly, the effects of mevastatin could be reversed by addition of mevalonate, but not farnesyl- or geranylgeranylpyrophosphate, intermediate products of cholesterol synthesis, to the medium. These results suggest that HMG-CoA reductase inhibitors like mevastatin may enhance the antiproliferative effect of butyrate in colon cancer cells via induction of apoptosis together with a G0/G1 cell cycle arrest.

Our data suggest that 5-MTHF, being the key metabolite in both the folate and homocysteine metabolic pathway, is the main modulator of growth-promoting actions of homocysteine as well as antiproliferative effects of folate in colon cancer cells.

AIM:To correlate the significance of liver biochemical tests in diagnosing post orthotopic liver transplantation (OLT) biliary complications and to study their profile before and after endoscopic therapy. METHODS:Patients who developed biliary complications were analysed in detail for the clinical information, laboratory tests, treatment offered, response to it, follow up and outcomes. The profile of liver enzymes was determined. The safety, efficacy and outcomes of endoscopic retrograde cholangiography (ERC) were also analysed.RESULTS: 40 patients required ERC for 70 biliary complications. GGT was found to be > 3 times (388.1 ± 70.9 U/mL vs 168.5 ± 34.2 U/L, P = 0.007) and SAP > 2 times (345.1 ± 59.1 U/L vs 152.7 ± 21.4 U/L, P = 0.003) the immediate post OLT values. Most frequent complication was isolated anastomotic strictures in 28 (40%). Sustained success was achieved in 26 (81%) patients. CONCLUSION:Biliary complications still remain an important problem post OLT. SAP and GGT can be used as early, non-invasive markers for diagnosis and also to assess the adequacy of therapy. Endoscopic management is usually effective in treating the majority of these biliary complications.

No abstract

The aim of this study is to compare the histological grading of acute organ rejection according to the Banff score with intracellular interleukin-2 (IL-2) concentrations in cytotoxic CD8+ T cells from peripheral blood samples. 66 recipients after liver transplantation and 20 healthy controls were included into this study. Blood samples of liver transplant recipients were collected beside routine visits or, in case of suspected organ rejection, with additional liver biopsy. For cytometry, the blood cells were stained with CD3, CD8 and intracellular-IL-2. The percentage of cells with detectable intracellular IL-2 was significantly increased in patients with acute rejection (n = 7, P < 0.001, t Test) compared to recipients without rejection. The percentage of cells with detectable intracellular IL-2 (mean +/- SEM) was 7.6 +/- 0.9% in rejection patients, 2.3 +/- 0.22% in stable liver transplant recipients, and 14 +/- 2.99% in healthy controls. Intracellular IL-2 correlates to the Banff score in rejection patients (Spearmans-rho = 0.81, P < 0.05). This cytometric method shows a good sensitivity (71%) with a cut-off based on a high specificity of 95% for histological proven organ rejection in our study cohort. Measurement of intracellular IL-2 in cytotoxic CD8+ T-lymphocytes by flow cytometry correlates very well to the histological grading according to the Banff score and shows a good sensitivity and excellent specificity in acute organ rejection.

In the German hospital reimbursement system (G-DRG) endoscopic procedures are listed in cost center 8. For reimbursement between hospital departments and external providers outdated or incomplete catalogues (e. g. DKG-NT, GOÄ) have remained in use. We have assessed the cost for endoscopic procedures in the G-DRG-system. To assess the cost of endoscopic procedures 74 hospitals, annual providers of cost-data to the Institute for the Hospital Remuneration System (InEK) made their data (2011 - 2015; § 21 KHEntgG) available to the German-Society-of-Gastroenterology (DGVS) in anonymized form (4873 809 case-data-sets). Using cases with exactly one endoscopic procedure (n = 274 186) average costs over 5 years were calculated for 46 endoscopic procedure-tiers. Robust mean endoscopy costs ranged from 230.56 € for gastroscopy (144 666 cases), 276.23 € (n = 32 294) for a simple colonoscopy, to 844.07 € (n = 10 150) for ERCP with papillotomy and plastic stent insertion and 1602.37 € (n = 967) for ERCP with a self-expanding metal stent. Higher costs, specifically for complex procedures, were identified for University Hospitals. For the first time this catalogue for endoscopic procedure-tiers, based on § 21 KHEntgG data-sets from 74 InEK-calculating hospitals, permits a realistic assessment of endoscopy costs in German hospitals. The higher costs in university hospitals are likely due to referral bias for complex cases and emergency interventions. For 46 endoscopic procedure-tiers an objective cost-allocation within the G-DRG system is now possible. By international comparison the costs of endoscopic procedures in Germany are low, due to either greater efficiency, lower personnel allocation or incomplete documentation of the real expenses.