Márk Juhász

Efficacy and Safety of the Biosimilar Infliximab CT-P13 Treatment in Inflammatory Bowel Diseases: A Prospective, Multicentre, Nationwide Cohort

BACKGROUND AND AIMS Biosimilar infliximab CT-P13 is approved for all indications of the originator product in Europe. Prospective data on its efficacy, safety, and immunogenicity in inflammatory bowel diseases are lacking. METHODS A prospective, nationwide, multicentre, observational cohort was designed to examine the efficacy, safety, and immunogenicity of CT-P13 infliximab biosimilar in the induction treatment of Crohns disease [CD] and ulcerative colitis [UC]. Demographic data were collected and a harmonised monitoring strategy was applied. Early clinical remission, response, and early biochemical response were evaluated at Week 14, steroid-free clinical remission was evaluated at Week 30. Therapeutic drug level was monitored using a conventional enzyme-linked immunosorbent assay. RESULTS In all, 210 consecutive inflammatory bowel disease [126 CD and 84 UC] patients were included in the present cohort. At Week 14, 81.4% of CD and 77.6% of UC patients showed clinical response and 53.6% of CD and 58.6% of UC patients were in clinical remission. Clinical remission rates at Week 14 were significantly higher in CD and UC patients who were infliximab naïve, compared with those with previous exposure to the originator compound [p < 0.05]. Until Week 30, adverse events were experienced in 17.1% of all patients. Infusion reactions and infectious adverse events occurred in 6.6% and 5.7% of all patients, respectively. CONCLUSIONS This prospective multicentre cohort shows that CT-P13 is safe and effective in the induction of clinical remission and response in both CD and UC. Patients with previous infliximab exposure exhibited decreased response rates and were more likely to develop allergic reactions.

Differential Expression and Function of Caveolin-1 in Human Gastric Cancer Progression

Caveolin-1 is a scaffold protein of caveolae that acts as a tumor modulator by interacting with cell adhesion molecules and signaling receptors. The role of caveolin-1 in the pathogenesis of gastric cancer (GC) is currently unknown. We show by confocal immunofluorescence microscopy and immunohistochemistry of biopsies from GC patients (n = 41) that the nonneoplastic mucosa expressed caveolin-1 in foveolar epithelial cells and adjacent connective tissue. GC cells of only 3 of 41 (7%) patients expressed caveolin-1 and were all of the intestinal type. Quantitative PCR and Western blotting confirmed that, compared with nonneoplastic tissue, the overall caveolin-1 mRNA was decreased in 14 of 19 (74%) GC patients and protein in 7 of 13 (54%), respectively. Strong caveolin-1 reactivity was found in the nonepithelial compartment (myocytes, fibroblasts, perineural, and endothelial cells) in both tumor-free and GC samples. In a series of human GC cell lines, caveolin-1 expression was low in cells derived from a primary tumor (AGS and SNU-1) but was increased in cell lines originating from distant metastases (MKN-7, MKN-45, NCI-N87, KATO-III, and SNU-5). Ectopic expression of caveolin-1 in AGS cells decreased proliferation but promoted anchorage-independent growth and survival. RNAi-mediated knockdown of endogenous caveolin-1 in MKN-45 cells accelerated cell growth. These data indicate that caveolin-1 exhibits a stage-dependent differential expression and function in GC and may thereby contribute to its pathogenesis.

Detection of Methylated Septin 9 in Tissue and Plasma of Colorectal Patients with Neoplasia and the Relationship to the Amount of Circulating Cell-Free DNA

Background Determination of methylated Septin 9 (mSEPT9) in plasma has been shown to be a sensitive and specific biomarker for colorectal cancer (CRC). However, the relationship between methylated DNA in plasma and colon tissue of the same subjects has not been reported. Methods Plasma and matching biopsy samples were collected from 24 patients with no evidence of disease (NED), 26 patients with adenoma and 34 patients with CRC. Following bisulfite conversion of DNA a commercial RT-PCR assay was used to determine the total amount of DNA in each sample and the fraction of mSEPT9 DNA. The Septin-9 protein was assessed using immunohistochemistry. Results The percent of methylated reference (PMR) values for SEPT9 above a PMR threshold of 1% were detected in 4.2% (1/24) of NED, 100% (26/26) of adenoma and 97.1% (33/34) of CRC tissues. PMR differences between NED vs. adenoma and NED vs. CRC comparisons were significant (p<0.001). In matching plasma samples using a PMR cut-off level of 0.01%, SEPT9 methylation was 8.3% (2/24) of NED, 30.8% (8/26) of adenoma and 88.2% (30/34) of CRC. Significant PMR differences were observed between NED vs. CRC (p<0.01) and adenoma vs. CRC (p<0.01). Significant differences (p<0.01) were found in the amount of cfDNA (circulating cell-free DNA) between NED and CRC, and a modest correlation was observed between mSEPT9 concentration and cfDNA of cancer (R2 = 0.48). The level of Septin-9 protein in tissues was inversely correlated to mSEPT9 levels with abundant expression in normals, and diminished expression in adenomas and tumors. Conclusions Methylated SEPT9 was detected in all tissue samples. In plasma samples, elevated mSEPT9 values were detected in CRC, but not in adenomas. Tissue levels of mSEPT9 alone are not sufficient to predict mSEPT9 levels in plasma. Additional parameters including the amount of cfDNA in plasma appear to also play a role.

The impact of matrix metalloproteinases and their tissue inhibitors in inflammatory bowel diseases

Background: It has been suggested that matrix metalloproteinases (MMPs) may play a role in the pathogenesis of inflammatory bowel diseases (IBD). However, the impact of serum MMPs and their inhibitors [tissue inhibitors of metalloproteinases (TIMPs)] have scarcely been investigated in the same experimental setting in ulcerative colitis (UC) and Crohn’s disease (CD) as well as their correlation with IBD activity. Methods: MMP-2, MMP-7, MMP-9, TIMP-1 and TIMP-2 serum antigen levels were determined in 23 patients with UC, 25 patients with CD and 10 healthy control patients by enzyme-linked immunoassay technique. Statistical analysis with one-way ANOVA and Student’s t tests was performed. A linear regression analysis or a Spearman’s r test was used to assess correlation. Differences were considered significant with p < 0.05. Results: Serum antigen concentrations of MMP-9, TIMP-1 and TIMP-2 were significantly higher in UC and CD patients compared to controls. MMP-7 was also significantly higher in CD compared with controls. Elevated MMP-9 and TIMP-1 antigen levels showed significant positive correlation with disease activity of IBD. MMP-2 and TIMP-2 levels inversely correlated with CD activity. Significant correlations were found between MMP-9/TIMP-1 and MMP-2/TIMP-2 antigen levels in both UC and CD. Conclusions: We demonstrated that serum antigen concentrations of MMP-9, TIMP-1 and TIMP-2 were significantly increased in patients with UC and CD compared to controls. Our results suggest that MMPs and TIMPs may contribute to the inflammatory and remodeling processes in IBD. Serum MMP-9 and TIMP-1 might be useful as additional biomarkers in the assessment of IBD activity.

The Behavior of Matrix Metalloproteinase-9 in Lymphocytic Colitis, Collagenous Colitis and Ulcerative Colitis

Matrix metalloproteinases play an important role in extracellular matrix remodelling. It has been proposed that matrix metalloproteinase-9 (MMP-9) is involved in epithelial damage in ulcerative colitis (UC). However, to our knowledge, no data are available in terms of MMP-9 expression in microscopic colitis. Determination of mucosal protein expression levels of MMP-9 in lymphocytic colitis (LC), collagenous colitis (CC) and UC. MMP-9 immunohistochemical expressions were analyzed in paraffin-embedded tissue samples by immunohistochemistry including patients with LC, CC, UC, active diverticulitis, inactive diverticular disease and healthy control subjects. UC was also subgrouped according to the severity of inflammation. Immunostaining was determined semiquantitatively. Independent colonic biopsies from healthy and severe UC cases were used for gene expression analyses. For further comparison MMP-9 serum antigen levels were also determined in patients with UC and control patients without macroscopic or microscopic changes during colonoscopy. MMP-9 mucosal expression was significantly higher in UC (26.7 ± 19.5%) compared to LC (6.6 ± 9.3%), CC (6.4 ± 7.6%), active diverticulitis (5.33 ± 2.4%), inactive diverticular disease (5.0 ± 2.2%) and controls (6.3 ± 2.6%) (P < 0.001). The immunohistochemical expression of MMP-9 in LC and CC was similar as compared to controls. MMP-9 expression was significantly higher in each inflammatory group of UC compared to controls (mild: 11.0 ± 2.8%, moderate: 23.9 ± 3.7%, severe UC: 52.6 ± 3.9% and 6.3 ± 2.6%, respectively, P < 0.005). The gene expression microarray data and RT-PCR results demonstrated a significantly higher expression of MMP-9 in severely active UC compared to healthy controls (P < 0.001). Significantly higher MMP-9 serum antigen concentrations were observed in UC patients compared with the control group (P < 0.05). MMP-9 seems to play no role in the inflammatory process of LC and CC. In contrast, the mucosal up-regulation of MMP-9 correlated with the severity of inflammation in UC. The increased MMP-9 expression could contribute to the severity of mucosal damage in active UC.

Effect of Proton-Pump Inhibitor Therapy on Serum Chromogranin A Level.

Background: The neuroendocrine marker, chromogranin A (CgA) increases during medium- or long-term proton-pump inhibitor (PPI) treatment. Aims: To analyze the effect of ultra-short-term and diverse dose of PPI therapy on serum CgA and gastrin levels and evaluate the effect of PPI treatment cessation. Patients and Methods: Fasting serum CgA and gastrin were determined in newly diagnosed gastroesophageal reflux disease (GERD) patients (n = 54) treated with diverse doses of PPI during a 28-day period, in patients treated with PPIs for at least 6 months (n = 42), and in subjects where PPI treatment could be stopped (n = 11). Results: A significant stepwise increase of CgA levels was observed after 5 days during the 28-day period treatment with all PPI doses. Gastrin increased significantly also in the standard and high-dose PPI subgroups. The most prominent increase of CgA was observed in the high-dose PPI subgroup. Serum CgA and gastrin were markedly elevated after 6 months of PPI treatment, and decreased significantly after 5 days of PPI discontinuation. Conclusions: Serum CgA increases significantly even after ultra-short-term (5 days) PPI therapy. After long-term treatment, 5-day cessation of PPI therapy is sufficient to decrease significantly both CgA and gastrin levels.

Helicobacter pylori and Antrum Erosion‐Specific Gene Expression Patterns: The Discriminative Role of CXCL13 and VCAM1 Transcripts

Background and Aims:  Chronic Helicobacter pylori infection affects approximately half of the world, leads to chronic gastritis and peptic ulceration, and is linked to gastric carcinoma. Our aims were to compare the gene expression profile (GEP) of H. pylori‐positive and H. pylori‐negative gastric erosions and adjacent mucosa to explain the possible role and response to H. pylori infection and to get erosion‐related mRNA expression patterns.

Current standings of the proton pump inhibitor and clopidogrel co-therapy: review on an evolving field with the eyes of the gastroenterologist.

The negative effect of proton pump inhibitors (PPI) on the antiplatelet function of clopidogrel has only recently emerged on the horizon of cardiological interest. To date, one can only find 10 peer-reviewed papers on PubMed on this issue, although the increasing activity is unquestionable. Besides publications, conference reports and official web sites are therefore important sources of information. In this field, the first step was made by an experimental study proving the adverse effect of omeprazole on clopidogrel function. Consequently, retrospective studies reported a significant increase of major adverse cardiovascular events among patients taking the combination of omeprazole and clopidogrel. Based on the paucity of quality data and limitations of studies conducted on this interaction, some are still reluctant to confirm the pathogenic role of PPI and clopidogrel interaction in the development of reinfarctions. One step further ahead, admitting the risks related to the combination of these two drugs, the next question to be decided is whether we face a class effect, or thanks to the different metabolic pathways there are indeed relevant differences among PPIs. There is a lot at stake, since the volume of patients taking the dual aspirin-clopidogrel antiplatelet therapy and thereby needing gastroprotection is immense, rendering a huge responsibility to the societies and committees who are making proposals on the selection of appropriate PPIs.

Increased p53 expression in the malignant transformation of Barrett's esophagus is accompanied by an upward shift of the proliferative compartment.

Neoplastic progression in Barrett’s esophagus (BE) occurs by a multistep process associated with early molecular and morphological changes. This study evaluated cell proliferation and p53 expression and their correlation in the development and progression of esophageal adenocarcinoma. PCNA and p53 expressions were analyzed in biopsy samples by immunohistochemistry including patients with reflux esophagitis, BE, BE with concomitant esophagitis, Barrett’s dysplasia, esophageal adenocarcinoma and a control group without any histological changes. Progressive increase in cell proliferation and p53 expression was found in the sequence of malignant transformation of the esophageal mucosa. While cell proliferation was significantly lower in the control group compared with all other groups, there was no increase in p53 expression of esophageal tissues that were negative for dysplasia. Dysplastic BE tissues revealed significantly higher cell proliferation and p53 expression levels compared to BE, reflux esophagitis or BE with concomitant esophagitis. Both, cell proliferation and p53 expression were significantly higher in adenocarcinoma compared to BE or Barrett’s dysplasia. Interestingly, while just BE with concomitant esophagitis showed significantly higher p53 expression levels than BE, both, BE with concomitant esophagitis and reflux esophagitis revealed significantly higher cell proliferation levels compared to BE. Alterations of cell proliferation and p53 expression showed a strong correlation. Simultaneous activation of cell proliferation and p53 expression strongly suggest their association with esophageal epithelial tumor genesis and particularly, their specific role in the biology of esophageal adenocarcinoma. Quantification of these parameters in BE is thought to be useful to identify patients at higher risk for progression to adenocarcinoma.

Expression of caveolin-1 in gastrointestinal and extraintestinal cancers

Caveolae are uniform vesicular invaginations of the cell membrane. Caveolin-1 is responsible for the formation of caveolae and plays a key role in membrane traffic and signal transduction. The contribution of caveolin-1 to carcinogenesis has been widely investigated; however, the expression pattern of caveolin-1 is controversial both in gastrointestinal and extraintestinal cancers. Most of the results based on cancer cell line experiments suggest that caveolin-1 might act as a tumor-suppressor gene. On the contrary, several studies on the expression of caveolin-1 in tumor tissues indicate a possible tumor-promoting effect of caveolin-1. In this article we summarize the divergent results of caveolin-1 expression in gastrointestinal and extraintestinal cancer regarding possible future therapeutic implications.