title: Annexin A2 localizes to the basal epithelial layer and is down-regulated in dysplasia and head and neck squamous cell carcinoma.
abstract: Annexin A2 is a highly expressed gene with important roles in cell membrane physiology and is frequently dysregulated in cancer. The objective of this study was to determine the pattern of expression and prognostic significance of annexin A2 protein in head and neck squamous cell carcinoma. We assessed both quantitative changes and qualitative distribution of annexin A2 mRNA and protein expression in normal and diseased tissues by immunohistochemistry, immunofluorescence and in situ hybridization. Annexin A2 expression was confined to the basal and suprabasal cells of normal epithelium and the protein cellular location was consistently observed at the cell membrane. Expression levels correlated with histopathological grade, showing significant suppression in moderately and poorly differentiated tumours. We conclude that annexin A2 exhibits a characteristic pattern of expression, distinct from other annexins and suggestive of a cell-specific functional role. The marked reduction of annexin A2 in poorly differentiated tumours and dysplastic tissue is expected to result in a loss of function aimed at the coordination of membrane signalling enzyme complexes, actin polymerization and extracellular matrix proteolysis. The phenotypic consequences may become manifest in an alteration of epithelial tissue growth and remodelling with secondary influence on tumour development, progression and metastasis.
authors.affiliation: Instituto Universitario de Oncologia del Principado de Asturias, Oviedo, Spain. penaem@unican.es
authors.forename: Emma
authors.initials: E
authors.lastname: Pena-Alonso
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Rodrigo
authors.forename: Iñigo Casafont
authors.initials: IC
authors.lastname: Parra
authors.forename: Juana Maria Garcia
authors.initials: JM
authors.lastname: Pedrero
authors.forename: Maria Victoria Gonzalez
authors.initials: MV
authors.lastname: Meana
authors.forename: Carlos Suarez
authors.initials: CS
authors.lastname: Nieto
authors.forename: Manuel F
authors.initials: MF
authors.lastname: Fresno
authors.forename: Reginald O
authors.initials: RO
authors.lastname: Morgan
authors.forename: M Pilar
authors.initials: MP
authors.lastname: Fernandez
mesh_terms: D017306:Annexin A2 / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D015536:Down-Regulation; D004847:Epithelial Cells / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006258:Head and Neck Neoplasms / Q000378:metabolism*; D006801:Humans; D017403:In Situ Hybridization; D011230:Precancerous Conditions / Q000378:metabolism
chemical_list: D017306:Annexin A2