RESUMO
Stabilin-1 is an endocytotic scavenger receptor, specifically expressed by non-continuous sinusoidal endothelial cells in the liver, spleen and lymph nodes and by M2 or alternatively activated macrophages in human malignancies. We analysed paraffin-embedded tissue of melanocytic lesions and granulomatous diseases for stabilin-1 expression, using the human/murine RS1 antibody. The specificity of the RS1 staining was confirmed in a knockout model, as only M2-like tumor-associated macrophages and vessels of a B16F10 melanoma in wild type mice stained positive; while staining of tumor-associated macrophages and vessels originating from stabilin-1 deficient mice remained negative for stabilin-1 specific antibody RS1. In human specimens, the RS1 antibody stained tumor-associated macrophages in all pathological stages of melanoma. In addition, five cases of juvenile xanthogranulomas and one case of necrobiotic xanthogranuloma were strongly stabilin-1 positive, while Th-1 cytokine dominated granulomatous diseases such as sarcoidosis and granulomatous leprosy were negative. Stabilin-1 positive vessels were found in all analysed non-Langerhans cell histiocytoses and melanocytic lesions. No stabilin-1 positive vessels were present in any other granulomatous diseases.
Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Histiocitose de Células não Langerhans/metabolismo , Macrófagos/metabolismo , Xantogranuloma Necrobiótico/metabolismo , Nevo Pigmentado/metabolismo , Receptores de Retorno de Linfócitos/metabolismo , Neoplasias Cutâneas/metabolismo , Xantogranuloma Juvenil/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Moléculas de Adesão Celular Neuronais/deficiência , Moléculas de Adesão Celular Neuronais/genética , Modelos Animais de Doenças , Feminino , Xenoenxertos , Histiocitose de Células não Langerhans/patologia , Humanos , Imuno-Histoquímica , Linfonodos/metabolismo , Linfonodos/patologia , Macrófagos/patologia , Masculino , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Xantogranuloma Necrobiótico/patologia , Nevo Pigmentado/patologia , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Xantogranuloma Juvenil/patologiaRESUMO
Skin tumors are tumors arising from keratinocyte and from adnexal structures. Immunohistochemistry is very helpful in diagnosis of difficult cases in epithelial skin neoplasms, especially basal cell carcinoma (BCC) which is positive for BerEP4, a keratin marker, and mostly negative for epithelial membrane antigen (EMA). Squamous cell carcinoma cells are positive for EMA and cytokeratin, which are of higher molecular weight than those found in BCC. In contrast to BCC, trichoblastoma and trichoepithelioma are negative for androgen receptors. Of the malignant dermal spindle cell lesions, spindle cell squamous carcinoma is positive to 34 betaE12, desmoplasmic melanoma is positive to S100, and leiomyosarcoma is positive to desmin. Of the malignant pagetoid cells, Paget's disease is positive to CK7 and cam5.2, whereas the pagetoid variant of Bowen's disease is positive to CK 5/6. Melanoma in-situ is positive to both S100 and melan-A. Immunohistochemistry is an extremely valuable adjunct to standard morphologic diagnosis in diagnostic pathology. Diagnosis of epithelial tumor depends largely on morphological features but, in rare cases, immunohistochemical stains are needed for definitive diagnosis.