Mucin-1 expression and localization in epithelial cells shows characteristic and distinct patterns in inflammatory...

Alterations in colonic mucus secretion are linked to the induction and maintenance of inflammation during inflammatory bowel disease (IBD) and its progression to colorectal cancer (CRC). MUC1, a multifunctional glycoprotein, is the best studied cell surface mucin in mouse models of IBD and CRC. However, little information on MUC1 expression and localization in different types of pathologic human colon mucosa is available. In this work, expression and subcellular localization of MUC1 in different types of diseased human colon mucosa from a cohort of Tunisian patients is analyzed and correlated with the type of disorder. Colon tissue samples were obtained from 39 cases of CRC and 18 cases of IBD. 13 cases of normal adjacent colon mucosa tissues served as controls. Biopsies were subjected to immunohistochemical analysis of MUC1 expression. Signals were quantified densitometrically and characterized with regard to tissue and intracellular distribution. Results were then correlated with the different types of colon disorder. Immunohistochemical investigation of MUC1 in a cohort of inflammatory bowel diseases and colorectal cancer showed a significant divergence in the expression of MUC1 in terms intensity (18.96% ± 0.55 vs 27.26% ± 1.24 respectively; P=0.005) and localization between the two types of lesions (30.76% vs 70.96% respectively; P=0.0199). Our findings show divergent characteristic patterns for MUC1 expression and localization in different types of pathologic alterations of the colon mucosa. These results are of potential diagnostic and predictive clinical value.