RESUMO
Achieving a specific diagnosis of polycythemia vera (PV) and other myeloproliferative disorders (MPDs) is often costly and complex. However, the recent identification of a V617F mutation in the JH2 domain of the JAK2 gene in a high proportion of patients suffering from MPDs may provide confirmation of a diagnosis. This is an acquired mutation and, as such, may only be present in a small number of cells within a sample. There is therefore a clinical need for highly sensitive detection techniques. We have developed a sensitive real-time polymerase chain reaction (PCR)-based approach for both detection and quantification of the JAK2 V671F mutation load, which allows determination of mutation status without the need for prior purification of granulocytes. We have performed a comparison of this assay with two previously published detection methods. Although an amplification refractory mutation system (ARMS) was shown to be slightly superior in terms of sensitivity, our real-time PCR method provides the potential for quantification of the JAK2 V617F mutation, having potential future applications in the monitoring of minimal residual disease or predicting outcome of disease severity.
Assuntos
Janus Quinase 2/genética , Técnicas de Diagnóstico Molecular/métodos , Mutação de Sentido Incorreto/genética , Policitemia Vera/genética , Reação em Cadeia da Polimerase/métodos , Primers do DNA , Humanos , Sensibilidade e EspecificidadeRESUMO
Despite considerable advances in understanding the molecular pathogenesis of Wilms' tumor (WT), its cell biology is less well understood, partly due to the paucity of established WT cell lines. We report here the establishment of a new anaplastic WT cell line, 17.94, which expressed NCAM, SALL1, and CITED1-phenotypic features expected of metanephric blastema-derived cells. Treatment of 17.94 cells with 12-O-Tetradecanoylphorbol 13-acetate caused morphological changes, which led to reduced NCAM and SALL1 expression, but expression of vimentin was maintained, indicating a potential for stromal differentiation. The 17.94 cell line contained a TP53 mutation, consistent with the anaplastic histology of the original tumor, but lacked mutations in WT1, WTX, or CTNNB1, which are the other genes involved in WT pathogenesis. The 17.94 cells showed no loss of heterozygosity at 7p, 11p, or 16q; however, DNA hypermethylation was detected at several loci, including the H19 differentially methylated region (indicative of loss of imprinting of IGF2 at 11p15) and at the PCDH@ gene clusters at 5q31. The derivation of the 17.94 cell line should help to further dissect the genetic-epigenetic interactions involved in the pathogenesis of WT.
Assuntos
Carcinoma , Linhagem Celular Tumoral , Tumor de Wilms , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/patologia , Técnicas de Cultura de Células , Diferenciação Celular , Pré-Escolar , Metilação de DNA , Feminino , Humanos , Cariótipo , Moléculas de Adesão de Célula Nervosa/biossíntese , Proteínas Nucleares/biossíntese , Acetato de Tetradecanoilforbol/farmacologia , Transativadores , Fatores de Transcrição/biossíntese , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Vimentina/biossíntese , Proteínas WT1/genética , Tumor de Wilms/genética , Tumor de Wilms/metabolismo , Tumor de Wilms/patologia , beta Catenina/genéticaRESUMO
Intrathoracic extramedullary hematopoiesis is a rare entity, mostly observed in patients with hematologic disorders. Extramedullary hematopoiesis is usually asymptomatic and is often located in the lower paravertebral sulci and rarely in the pleura. We report the case of a 54-year-old man without hematologic disorder or pleural malignancy who had a massive bilateral chylothorax develop due to primary pleural extramedullary hematopoiesis. He was successfully treated by bilateral video thoracoscopic talc pleurodesis and low-dose radiotherapy.