Conde, IsabelLobo, María V TZamora, JavierPérez, JulioGonzález Sánchez, Francisco JesúsAlba Conejo, EmilioFraile, BenitoPaniagua, RicardoArenas, María I2013-03-122013-03-122008-06-19Conde I, Lobo MV, Zamora J, Pérez J, González Sánchez FJ, Alba Conejo E, et al. Human pregnane X receptor is expressed in breast carcinomas, potential heterodimers formation between hPXR and RXR-alpha. BMC Cancer; 8:174http://hdl.handle.net/10668/820Journal Article;BACKGROUND The human pregnane X receptor (hPXR) is an orphan nuclear receptor that induces transcription of response elements present in steroid-inducible cytochrome P-450 gene promoters. This activation requires the participation of retinoid X receptors (RXRs), needed partners of hPXR to form heterodimers. We have investigated the expression of hPXR and RXRs in normal, premalignant, and malignant breast tissues, in order to determine whether their expression profile in localized infiltrative breast cancer is associated with an increased risk of recurrent disease. METHODS Breast samples from 99 patients including benign breast diseases, in situ and infiltrative carcinomas were processed for immunohistochemistry and Western-blot analysis. RESULTS Cancer cells from patients that developed recurrent disease showed a high cytoplasmic location of both hPXR isoforms. Only the infiltrative carcinomas that relapsed before 48 months showed nuclear location of hPXR isoform 2. This location was associated with the nuclear immunoexpression of RXR-alpha. CONCLUSION Breast cancer cells can express both variants 1 and 2 of hPXR. Infiltrative carcinomas that recurred showed a nuclear location of both hPXR and RXR-alpha; therefore, the overexpression and the subcellular location changes of hPXR could be considered as a potential new prognostic indicator.enpregnane X receptorWestern BlottingAncianoNeoplasia de la mamaCarcinoma ductal de mamaDimerizaciónSupervivencia sin EnfermedadInmunohistoquímicaEstadificación de NeoplasiasReceptores de EsteroidesReceptor alfa X RetinoideReceptores x RetinoideAdultoMediana edadHumanosFemeninoCarcinoma in situAnciano de 80 o más AñosMedical Subject Headings::Named Groups::Persons::Age Groups::Adult::AgedMedical Subject Headings::Named Groups::Persons::Age Groups::Adult::Aged::Aged, 80 and overMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Chemistry Techniques, Analytical::Electrophoresis::Blotting, WesternMedical Subject Headings::Diseases::Neoplasms::Neoplasms by Site::Breast NeoplasmsMedical Subject Headings::Diseases::Neoplasms::Neoplasms by Histologic Type::Neoplasms, Glandular and Epithelial::Carcinoma::Carcinoma in SituMedical Subject Headings::Diseases::Neoplasms::Neoplasms by Histologic Type::Neoplasms, Glandular and Epithelial::Carcinoma::Adenocarcinoma::Carcinoma, Ductal::Carcinoma, Ductal, BreastMedical Subject Headings::Phenomena and Processes::Chemical Phenomena::Biochemical Phenomena::Biochemical Processes::DimerizationMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Prognosis::Disease-Free SurvivalMedical Subject Headings::Check Tags::FemaleMedical Subject Headings::Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::HumansMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Clinical Laboratory Techniques::Cytological Techniques::Histocytochemistry::ImmunohistochemistryMedical Subject Headings::Named Groups::Persons::Age Groups::Adult::Middle AgedMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Prognosis::Neoplasm StagingMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Receptors, Cytoplasmic and Nuclear::Receptors, SteroidMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Receptors, Cytoplasmic and Nuclear::Receptors, Retinoic Acid::Retinoid X Receptors::Retinoid X Receptor alphaMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Receptors, Cytoplasmic and Nuclear::Receptors, Retinoic Acid::Retinoid X ReceptorsMedical Subject Headings::Named Groups::Persons::Age Groups::Adultresearch article18565212open access10.1186/1471-2407-8-1741471-2407PMC2442113