Immunohistochemical expression of sulfhydryl oxidase (QSOX1) in pediatric medulloblastomas.

BACKGROUND: Medulloblastoma is a malignant, invasive embryonal tumor of the cerebellum and accounts for 20% of intracranial tumors in children. QSOX1, whose functions include formation of disulphide bridges, which are needed for correct protein folding and stability, formation of the extracellular matrix, regulation of the redox status and cell cycle control, appears to be involved in apoptosis in pathological states such as cancer. Thus, the aim of this study was to investigate the immunohistochemical expression of QSOX1 in medulloblastomas and nonneoplastic cerebellum. METHODS: Histology blocks of pediatric medulloblastomas were separated and two representative areas of the tumors and non-neoplastic cerebellum samples were used to construct tissue microarrays (TMAs) that were stained with an anti-QSOX1 antibody, and the slides were read using image analysis software. RESULTS: QSOX1 immunoexpression was observed in the non-neoplastic cerebellum samples and the medulloblastoma samples. There was no statistically significant relationship between QSOX1 immunopositivity in the medulloblastoma samples and the clinical and pathological variables. CONCLUSIONS: Although QSOX1 did not prove useful for stratifying patients into risk groups, tumor cells and the fibrillar extracellular matrix were positive for this marker, indicating that this enzyme may be involved in the pathogenesis of medulloblastoma. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1822040654139436.

A expressão imuno-histoquímica de Ki67, EGFR E TRKC e sua correlação com fatores prognósticos em meduloblastomas / Immunohistochemical expression of Ki67, EGFR and TRKC and their correlation with prognostic factors in medulloblastoma

Introduction: Medulloblastoma is a malignant embryonal tumor of the cerebellum with poor prognosis. The treatment is based only on clinical criteria, such as risk group that only considers age, extent of tumor resection, recurrence, and metastasis. Objective: To evaluate a possible relationship between the immunoexpression of biomarkers (Ki67, receptor neutrophin-3 [TRKC], epidermal growth factor receptor [EGFR], B-cell lymphoma 2 [Bcl-2], and cyclin-D1), and the classical clinical prognostic factors of medulloblastoma. Material and method: thirty-five samples of pediatric medulloblastoma free of neoadjuvant chemotherapy were separated and reviewed for their histopathological classification; two areas representative of tumor were used in the construction of tissue microarrays. The following clinical data from 29 patients were used for comparison with the biomarkers expression: patient's age, presence or absence of complete tumor resection, staging patient's risk group, presence or absence of metastases, presence or absence of postoperative chemotherapy, and presence or absence of recurrence. Clinical follow-up of the study ranged from two to thirteen years, and cases with fatal outcome were also analyzed. Results: Patients with upper age showed higher expression of TRKC (p = 0.033). There was inversely proportional and statistically significant correlation between TRKC and Ki67 (p = 0.027). There was no statistical significance in the analysis of EGFR, Bcl2, and cyclin-D1. Conclusion: The immunoexpression of TRKC might be considered a biomarker related to tumors with better prognosis in patients with medulloblastoma, contributing to better risk groups' stratification...

Introdução: O meduloblastoma é o tumor maligno do cerebelo com prognóstico reservado. Seu tratamento baseia-se somente em critérios clínicos, como os grupos de risco que levam em consideração apenas idade, extensão de ressecção, recidiva e metástase. Objetivo: Avaliar uma possível relação entre a imunoexpressão de biomarcadores (Ki67, receptor de neurotrofina-3 [TRKC], epidermal growth factor receptor [EGFR], B-cell lymphoma 2 [Bcl-2] e ciclina-D1) e os fatores prognósticos clínicos clássicos dos meduloblastomas. Material e método: Trinta e cinco amostras de meduloblastomas pediátricos livres de tratamento quimioterápico neoadjuvante foram separadas e revisadas quanto a sua classificação histopatológica, sendo duas áreas representativas do tumor utilizadas na construção de arranjos teciduais em matriz. Os seguintes dados clínicos de 29 pacientes foram utilizados para comparação com a expressão dos biomarcadores: idade do paciente, presença ou não de ressecção tumoral completa, estadiamento do paciente em grupo de risco, presença ou não de metástases, presença ou não de tratamento quimioterápico pós-cirúrgico e presença ou não de recidivas. O tempo de seguimento clínico do estudo variou de dois a treze anos, e os casos com desfecho fatal foram também analisados. Resultados: Os pacientes com idade mais elevada apresentaram expressão maior de TRKC (p = 0,033). Houve correlação inversamente proporcional e estatisticamente significativa entre o TRKC e o Ki67 (p = 0,027). Não houve relevância estatística nas análises do EGFR, Bcl-2 e ciclina-D1. Conclusão: A imunoexpressão do TRKC pode vir a ser considerada um biomarcador relacionado com tumores de melhor prognóstico em pacientes com meduloblastoma, contribuindo para uma melhor estratificação dos grupos de risco...

Immunohistochemistry analysis of pulmonary infiltrates in necropsy samples of children with non-pandemic lethal respiratory infections (RSV; ADV; PIV1; PIV2; PIV3; FLU A; FLU B).

BACKGROUND: Acute viral respiratory infections represent a globally important cause of morbidity and mortality in childhood. An individual's cellular response appears to play a critical role in recovery from infections, given that individuals with impaired cellular immunity, congenital or acquired, have more severe diseases and secrete the virus for longer periods. OBJECTIVES: The aim of this study was to immunohistochemically evaluate the expression of the cell surface antigens CD4, CD8, CD25, CD14 and CD74, in pneumonic infiltrates in the alveolar septa using paraffin-embedded lung samples from autopsies of immunocompetent children who died of lethal, non-pandemic, severe acute respiratory infections. STUDY DESIGN: From 794 cases of pediatric autopsies of patients with severe respiratory disease (between 1960 and 2004), 193 cases were selected for this study. To identify subpopulations of inflammatory cells in the alveolar septa, cell surface antigen expression was assessed by immunohistochemistry using the following primary antibodies: anti-CD4, anti-CD8, anti-CD14, anti-CD25 and anti-CD74. RESULTS: The TCD8+ lymphocyte count was higher in the virus-positive group (p = 0.04) and was also much higher among cases that were positive for more than three viral types (p = 0.016). There were fewer CD14+ cells in cases of AdV (adenovirus) infection (p = 0.002), and there was a predominance of CD74+ cells in the histopathological pattern defined as interstitial pneumonitis (p = 0.037). CONCLUSIONS: The results of this study demonstrate that TCD8+ lymphocytes present in the alveolar septa participate to a greater extent in the response toward viral pneumonia, while CD14+ cell numbers are often reduced in cases of AdV.