title: Expression of multidrug resistance-associated P-glycoprotein in feline tumours.
abstract: Permeability glycoprotein (P-gp) is a membrane-bound efflux pump that mediates the active transmembrane transport of a variety of substrates. Several studies in human and canine normal and neoplastic tissues indicate that P-gp is involved in resistance to chemotherapy and in the development of multidrug resistance (MDR). The purpose of this study was to evaluate P-gp expression with the monoclonal antibody C494 in common feline tumours from 88 patients not pretreated with chemotherapy. Tumours arising from tissues with intrinsic P-gp expression consistently showed positive labelling for P-gp in a cellular pattern identical to that described for the normal feline tissues. Both P-gp positive and negative tumour cells, however, were found in mammary gland tumours, lymphomas, mastocytomas and squamous cell carcinomas. Feline mammary gland tumours in particular showed strong membranous P-gp labelling, especially in areas with infiltrative growth and atypical cells, although this was not correlated with the grade of malignancy. These findings might have implications for future response to chemotherapy.
authors.affiliation: Department of Pathology, Bacteriology and Poultry Diseases, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium. sara.vanderheyden@ugent.be
authors.forename: S
authors.initials: S
authors.lastname: Van der Heyden
authors.forename: K
authors.initials: K
authors.lastname: Chiers
authors.forename: G
authors.initials: G
authors.lastname: Vercauteren
authors.forename: S
authors.initials: S
authors.lastname: Daminet
authors.forename: B
authors.initials: B
authors.lastname: Wegge
authors.forename: D
authors.initials: D
authors.lastname: Paepe
authors.forename: R
authors.initials: R
authors.lastname: Ducatelle
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000502:physiology*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology; D002371:Cat Diseases / Q000378:metabolism*; D002415:Cats; D018432:Drug Resistance, Multiple / Q000235:genetics*; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D005260:Female; D007150:Immunohistochemistry / Q000662:veterinary; D008223:Lymphoma / Q000145:classification / Q000378:metabolism / Q000473:pathology; D015674:Mammary Neoplasms, Animal / Q000378:metabolism / Q000473:pathology; D009369:Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000911:Antibodies, Monoclonal