title: MUC1 is a counter-receptor for myelin-associated glycoprotein (Siglec-4a) and their interaction contributes to adhesion in pancreatic cancer perineural invasion.
abstract: Perineural invasion in pancreatic adenocarcinoma, a common pathologic phenomenon whereby cancer cells invade and intimately contact the endoneurium of pancreatic nerves, is thought to contribute to both pain and local disease recurrence. MUC1, a type I transmembrane mucin that can affect the adhesive properties of cells, contains a large extracellular tandem repeat domain, which is heavily glycosylated in normal epithelia, but is overexpressed and differentially glycosylated in pancreatic cancer. This altered glycosylation includes the shortened core I O-glycans for monosialyl and disialyl T antigens. Myelin-associated glycoprotein (MAG), a membrane-bound protein expressed on oligodendrocytes and Schwann cells, binds myelin to neurons. MAG's preferred ligands are derivatives of the monosialyl and disialyl T antigen. We investigated whether MUC1 is a counter-receptor for MAG and if their interaction contributed to pancreatic perineural invasion. Results showed that MAG binds pancreatic cells expressing MUC1, that this binding is sialidase-sensitive, and that MAG physically associates with MUC1. Heterotypic adhesion assays between pancreatic cancer cells and Schwann cells revealed that increased expression of MUC1 or MAG enhanced adhesion. Conversely, specific inhibition of MAG or sialyl-T MUC1 partially blocked adhesion. Immunohistochemical analysis of pancreatic perineural invasion showed the expression of both MUC1 and MAG. These results support the hypothesis that the adhesive interactions between MUC1 and MAG are of biological significance in pancreatic cancer perineural invasion.
authors.affiliation: Eppley Institute for Research in Cancer and Allied Diseases and the Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198-6805, USA.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Swanson
authors.forename: Kimberly M
authors.initials: KM
authors.lastname: McDermott
authors.forename: Pankaj K
authors.initials: PK
authors.lastname: Singh
authors.forename: John P
authors.initials: JP
authors.lastname: Eggers
authors.forename: Paul R
authors.initials: PR
authors.lastname: Crocker
authors.forename: Michael A
authors.initials: MA
authors.lastname: Hollingsworth
mesh_terms: D000818:Animals; D016466:CHO Cells; D002448:Cell Adhesion; D045744:Cell Line, Tumor; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D047468:Immunoprecipitation; D037102:Lectins / Q000502:physiology*; D018396:Mucin-1 / Q000502:physiology*; D018992:Myelin-Associated Glycoprotein / Q000502:physiology*; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000473:pathology*; D010502:Perineum / Q000473:pathology*; D012583:Schwann Cells / Q000473:pathology; D063265:Sialic Acid Binding Immunoglobulin-like Lectins; D015398:Signal Transduction
chemical_list: D037102:Lectins; C060192:MUC1 protein, human; D018396:Mucin-1; D018992:Myelin-Associated Glycoprotein; D063265:Sialic Acid Binding Immunoglobulin-like Lectins