ABSTRACT
Alterations in the structure and/or quantity of mucins could alter the barrier function of mucus and play a role in initiating and maintaining mucosal inflammation in Crohn's disease. To investigate the hypothesis of a mucin gene defect in Crohn's disease, we analyzed the expression of the different mucin genes in the ileal mucosa of patients with Crohn's disease and controls. mRNA expression levels were assessed by a quantitative dot blot analysis and compared (i) between healthy and involved ileal mucosa of patients with Crohn's disease and (ii) between healthy mucosa of patients with Crohn's disease and controls. Expression of the different mucin genes was heterogeneous among controls and patients with Crohn's disease, except for MUC6 in controls. Nevertheless, MUC1 mRNA expression was significantly decreased in the involved ileal mucosa of patients with Crohn's disease when compared to the healthy mucosa (p = 0.02). Moreover, the expression levels of MUC3, MUC4, and MUC5B were significantly lower in both healthy and involved ileal mucosa of patients with Crohn's disease compared to controls (p < or = 0.05). The decrease of expression levels of some mucin genes (more particularly MUC3, MUC4, and MUC5B) in both healthy and involved ileal mucosa suggests a primary or very early mucosal defect of these genes in CD.
Subject(s)
Crohn Disease/genetics , Gene Expression Regulation , Mucins/genetics , Adolescent , Adult , Aged , Biopsy, Needle , Humans , Ileum/chemistry , Ileum/pathology , Intestinal Mucosa/chemistry , Intestinal Mucosa/pathology , Male , Middle Aged , RNA, Messenger/analysis , Reference Values , Sensitivity and Specificity , Statistics, NonparametricABSTRACT
BACKGROUND & AIMS: Rectosigmoid villous adenomas (RVAs) account for approximately 10% of all colorectal tumors. They have distinct pathological features, including abundant mucus secretion, possible malignant transformation, and multiple recurrences after conservative treatment. The aim of this study was to determine the nature of any changes in mucin gene expression in RVAs. METHODS: In situ hybridization was used to examine mucin messenger RNA expression in a series of 22 patients with an RVA. Five normal rectal and colonic mucosae and five rectal adenocarcinomas were used as controls. RESULTS: In the 22 RVAs, we found an overexpression of MUC2 and an aberrant expression of MUC5AC. This MUC5AC expression was more intense in RVAs with low-grade dysplasia than in those cases with high-grade dysplasia. Moreover, in 4 cases, it was detected at a distance from the tumor in areas previously considered as normal by endoscopic and histological examination. CONCLUSIONS: MUC5AC seems to be a specific marker for RVAs and thus may be useful for the early detection of RVA recurrences after endoscopic laser treatment.
Subject(s)
Adenoma, Villous/genetics , Colorectal Neoplasms/genetics , Gene Expression , Mucins/genetics , Adenoma, Villous/pathology , Base Sequence , Colon/physiopathology , Colorectal Neoplasms/pathology , Humans , In Situ Hybridization , Intestinal Mucosa/physiopathology , Molecular Sequence Data , Oligonucleotide Probes/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/metabolismABSTRACT
The study consists in adapting two methods allowing estimation of proteins in cerebrospinal fluid and urine on a centrifugal analyzer using Coomassie Blue-SDS and benzethonium chloride. Results obtained with the two reagents are compared with turbidimetric technic using trichloroacetic acid, by statistic methods.
