title: Evaluation of nucleolar organizer region-associated proteins in breast malignancy.
abstract: Nucleolar organizer regions (NORs) have been identified by means of an argyrophilic technique (Ag-NOR) in routinely processed, formalin-fixed paraffin sections of breast lesions. This method, which is novel in histopathology, reveals NORs as black dots in the nuclei of cells, by virtue of the argyrophilia of NOR-associated proteins. The number of Ag-NORs has been thought to be related to cellular activation and has recently been applied to non-Hodgkin's lymphomas and melanocytic skin lesions. It was found in the present study that the total number of Ag-NORs in malignant breast lesions significantly exceeded those of normal breast and benign lesions. The number of clumps of Ag-NORs, however, were not useful discriminators. Neither numbers of total Ag-NORs nor of clumps of Ag-NORs correlate with mitotic counts and it may be that their numbers relate to ploidy. It is suggested that the Ag-NOR technique will find increasing application as an adjunct to diagnostic histopathology.
mesh_terms: D000232:Adenofibroma / Q000473:pathology; D001050:Apocrine Glands / Q000473:pathology; D001943:Breast Neoplasms / Q000032:analysis* / Q000473:pathology / Q000648:ultrastructure; D002277:Carcinoma / Q000473:pathology; D005260:Female; D005348:Fibrocystic Breast Disease / Q000473:pathology; D006801:Humans; D008679:Metaplasia / Q000473:pathology; D009375:Neoplasms, Glandular and Epithelial; D009687:Nuclear Proteins / Q000032:analysis*; D009697:Nucleolus Organizer Region / Q000032:analysis / Q000473:pathology* / Q000648:ultrastructure; D013194:Staining and Labeling / Q000379:methods
chemical_list: D009687:Nuclear Proteins