RESUMEN
Osteosarcoma (OS) is a malignant bone tumor, with a peak of incidence in the second decade of life and possibly associated with the presence of germline mutations. Besides, clinicians have pointed to a second, rarer group of patients that develops OS before 10 years old. Here we access, through next-generation sequencing (NGS) strategy, the genetic alterations present in OS and blood samples from patients diagnosed before and during the second decade of life. A custom NGS panel, designed for the main alterations described in childhood and adolescence neoplasms, named Oncomine Childhood Cancer Research Assay (OCCRA©), was used. Of all 84 OS samples investigated, 42 (50%) presented some somatic variant, with TP53, MYC, CDK4, RB1 and PDGFRA genes harboring the most observed genetic variants. MYC CNVs were more frequent in tumors from patients diagnosed before 10 years old (X21= 5.18, p = 0.023). Additionally, patients diagnosed during the second decade of life presented a higher percentage of somatic and germline variants. Germline variants in TP53 and RB1 were found in 5 of the 11 (45.5%) patients analyzed. Clinical variables and tumor histopathological characteristics were also collected and correlated with our molecular findings.
Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Óseas/patología , Variaciones en el Número de Copia de ADN , Predisposición Genética a la Enfermedad , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mutación , Osteosarcoma/patología , Adolescente , Neoplasias Óseas/genética , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Osteosarcoma/genética , PronósticoRESUMEN
Myelodysplastic syndromes (MDS) and juvenile myelomonocytic leukemia (JMML) are rare hematopoietic stem cell diseases affecting children. Cytogenetics plays an important role in the diagnosis of these diseases. We report here the experience of the Cytogenetic Subcommittee of the Brazilian Cooperative Group on Pediatric Myelodysplastic Syndromes (BCG-MDS-PED). We analyzed 168 cytogenetic studies performed in 23 different cytogenetic centers; 84 of these studies were performed in patients with confirmed MDS (primary MDS, secondary MDS, JMML, and acute myeloid leukemia/MDS+Down syndrome). Clonal abnormalities were found in 36.9% of the MDS cases and cytogenetic studies were important for the detection of constitutional diseases and for differential diagnosis with other myeloid neoplasms. These data show the importance of the Cooperative Group for continuing education in order to avoid a late or wrong diagnosis.
Asunto(s)
Citogenética/métodos , Síndromes Mielodisplásicos/genética , Brasil , Niño , Preescolar , Humanos , Cariotipificación , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/mortalidad , Análisis de SupervivenciaRESUMEN
Myelodysplastic syndromes (MDS) and juvenile myelomonocytic leukemia (JMML) are rare hematopoietic stem cell diseases affecting children. Cytogenetics plays an important role in the diagnosis of these diseases. We report here the experience of the Cytogenetic Subcommittee of the Brazilian Cooperative Group on Pediatric Myelodysplastic Syndromes (BCG-MDS-PED). We analyzed 168 cytogenetic studies performed in 23 different cytogenetic centers; 84 of these studies were performed in patients with confirmed MDS (primary MDS, secondary MDS, JMML, and acute myeloid leukemia/MDS+Down syndrome). Clonal abnormalities were found in 36.9% of the MDS cases and cytogenetic studies were important for the detection of constitutional diseases and for differential diagnosis with other myeloid neoplasms. These data show the importance of the Cooperative Group for continuing education in order to avoid a late or wrong diagnosis.
Asunto(s)
Niño , Preescolar , Humanos , Citogenética/métodos , Síndromes Mielodisplásicos/genética , Brasil , Cariotipificación , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/mortalidad , Análisis de SupervivenciaRESUMEN
OBJECTIVES: The aim of this study was to verify whether intracystic injections of alpha-Interferon (IFN-alpha) in cystic craniopharyngiomas were able to reduce the tumor by activating the Fas apoptotic pathway. MATERIALS AND METHODS: Twenty-one patients with cystic craniopharyngiomas treated at the Pediatric Oncology Institute (IOP/GRAACC) of Federal University of São Paulo were submitted to intracystic chemotherapy with IFN-alpha. The tumor sizes of all patients were monitored and the apoptotic factor soluble FasL (sFasL) concentration was determined by ELISA (enzyme-linked immunosorbent assay) in tumor fluid samples from eight patients. RESULTS: There was a complete reduction in 11 patients, a partial response in seven, and a minor response in three patients. The concentration of sFasL was increased in all the eight patients examined concomitantly with the tumor size reduction. CONCLUSIONS: Our data demonstrated that the IFN-alpha was able to induce Fas-mediated apoptosis together with a reduction in the tumor size; such an observation may suggest the importance to investigate still unexplored mechanisms to be exploited in craniopharyngioma therapy.
Asunto(s)
Apoptosis/efectos de los fármacos , Craneofaringioma/terapia , Quimioterapia/métodos , Factores Inmunológicos/uso terapéutico , Interferón-alfa/uso terapéutico , Neoplasias Hipofisarias/terapia , Adolescente , Adulto , Niño , Preescolar , Craneofaringioma/patología , Ensayo de Inmunoadsorción Enzimática/métodos , Proteína Ligando Fas/metabolismo , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética/métodos , Masculino , Neoplasias Hipofisarias/patología , Estudios Retrospectivos , Tomógrafos Computarizados por Rayos XRESUMEN
Measurement of telomerase activity in clinically obtained tumor samples may provide important information for use as both a diagnostic marker and a prognostic indicator for patient outcome. In order to evaluate telomerase activity in tumor tissue without radiolabeling the product, we developed a simple telomeric repeat amplification protocol-silver-staining assay that is less time-consuming, is safe and requires minimal equipment. In addition, we determined the sensitivity of the silver-staining method by using extracts of telomerase-positive thyroid carcinoma cell lines which were serially diluted from 5,000 to 10 cells. Telomerase activity was also assayed in 19 thyroid tumors, 2 normal controls and 27 bone marrow aspirates. The results indicate that the technique permits the detection of telomerase activity from 5000 to as few as 10 cells. We propose that it could be immediately applicable in many laboratories due to the minimal amount of equipment required
Asunto(s)
Humanos , Tinción con Nitrato de Plata , Telomerasa , Telómero , Neoplasias de la Tiroides , Activación Enzimática , Biomarcadores de Tumor/metabolismo , Sensibilidad y Especificidad , Telomerasa , Células Tumorales CultivadasRESUMEN
Measurement of telomerase activity in clinically obtained tumor samples may provide important information for use as both a diagnostic marker and a prognostic indicator for patient outcome. In order to evaluate telomerase activity in tumor tissue without radiolabeling the product, we developed a simple telomeric repeat amplification protocol-silver-staining assay that is less time-consuming, is safe and requires minimal equipment. In addition, we determined the sensitivity of the silver-staining method by using extracts of telomerase-positive thyroid carcinoma cell lines which were serially diluted from 5,000 to 10 cells. Telomerase activity was also assayed in 19 thyroid tumors, 2 normal controls and 27 bone marrow aspirates. The results indicate that the technique permits the detection of telomerase activity from 5000 to as few as 10 cells. We propose that it could be immediately applicable in many laboratories due to the minimal amount of equipment required.
Asunto(s)
Tinción con Nitrato de Plata , Telomerasa/metabolismo , Telómero , Neoplasias de la Tiroides/enzimología , Biomarcadores de Tumor/metabolismo , Activación Enzimática , Humanos , Sensibilidad y Especificidad , Telomerasa/análisis , Células Tumorales Cultivadas/enzimologíaRESUMEN
Consistent cytogenetic abnormalities have been identified in a variety of human cancer cells and some of them are related to patiente prognosis. Fluorescence "in situ" hybridization (FISH) is a new methodology which can be used to detect cytogenetic anomalies within interphase cells. We present several aspects of FISH methodology and its application in several examples, including trisomy 8 detection with higt specificity and sensitivy in patients with myeloid leukemias; trisomy 12 detection with highter efficiency than conventional cytogenetics in patients with chronic lymphocytic leukemia; assessment of engraftment success; chimerism, and relapse in opposite sex bone marrow transplantation; and correlation of trisomy 7 with survival time in patients with prostate tumors. We discuss also some aspects of neuroblastoma tumors, one of the most frequent malignant solid tumor in childhood. At diagnosis the patient's age and tumor stage are the major prognostic factors. Favorable prognosis is associated with triploid karyotype, lack of 1 p abnormalities and absence of N-myc amplification, whereas unfavorable prognosis is associated with pseudodiploid or tetraploid karyotype, 1 p deletion and N-myc amplification. These abnormalities can be investigated quickly and effecctively in interphase cells using FISH.
Asunto(s)
Humanos , Lactante , Preescolar , Análisis Citogenético , Neoplasias/diagnóstico , Hibridación Fluorescente in Situ , Neuroblastoma/diagnóstico , Pronóstico , Trisomía/diagnósticoRESUMEN
Consistent cytogenetic abnormalities have been identified in a variety of human cancer cells and some of them are related to patient prognosis. Fluorescence "in situ" hybridization (FISH) is a new methodology which can be used to detect cytogenetic anormalies within interphase cells. We present several aspects of FISH methodology and its application in several examples, including trisomy 8 detection with high specificity and sensitivity in patients with myeloid leukemias; trisomy 12 detection with higher efficiency than conventional cytogenetics in patients with chronic lymphocytic leukemia; assessment of engraftment success, chimerism, and relapse in opposite sex bone marrow transplantation; and correlation of trisomy 7 with survival time in patients with prostate tumors. We discuss also some aspects of neroblastoma tumors, one of the most frequent malignant solid tumor in childhood. At diagnosis the patient's age and tumor stage are the major prognostic factors. Favorable prognosis is associated with triploid karyotype, lack of 1p abnormalities and absence of N-myc amplication, whereas unfavorable prognosis is associated with pseudodiploid or tetraploid karyotype, 1p deletion and N-myc amplication. These abnormalities can be investigated quickly and effectively in interphase cells using FISH.