RESUMEN

Recent innovations in the genomic understanding of medulloblastomas have provided new ways to explore this highly invasive malignant brain cancer arising from the cerebellum. Among the four different medulloblastoma subgroups described to date, the sonic hedgehog (SHH) genetic pathway is the pathway activated in the tumorigenesis of medulloblastoma. SHH-related medulloblastomas are usually of nodular/desmoplastic histology and frequently occur in children under the age of three, an age group highly susceptible to the acute and long-term effects of treatment. Several new drugs aimed at SHH modulation are currently under development. This review focuses on the role of arsenic trioxide, a drug well established in clinical practice and probably an under-explored agent in medulloblastoma management, in the SHH pathway.

Asunto(s)

Antineoplásicos/administración & dosificación , Arsenicales/administración & dosificación , Neoplasias Cerebelosas/tratamiento farmacológico , Proteínas Hedgehog/metabolismo , Meduloblastoma/tratamiento farmacológico , Óxidos/administración & dosificación , Adolescente , Antineoplásicos/farmacología , Trióxido de Arsénico , Arsenicales/farmacología , Neoplasias Cerebelosas/metabolismo , Niño , Preescolar , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Lactante , Meduloblastoma/metabolismo , Óxidos/farmacología , Transducción de Señal/efectos de los fármacos

RESUMEN

BACKGROUND: Polo-like kinase 1 (PLK1) is a conserved kinase that mediates various mitotic events. Compelling data have repeatedly demonstrated its upregulation in different neoplasia, being frequently associated with poor prognosis. However, in childhood acute lymphoblastic leukemia (ALL), no studies have yet been conducted. PROCEDURE: PLK1 expression and association with biological features were evaluated in 65 consecutively diagnosed childhood ALL samples by quantitative real-time PCR. Moreover, the effects of a specific PLK1 inhibitor, BI 2536, was tested against a panel of nine ALL cell lines at nanomolar concentrations (10, 50, 100 nM). RESULTS: The mRNA expression of PLK1 showed great variability in pediatric ALL, but no difference was evidenced compared to normal bone marrow. Additionally, no association was found between PLK1 mRNA expression with any clinical or biological features. Alternatively, high mRNA expression of PLK1 was present in ALL cell lines. In vitro treatment with BI 2536 strongly diminished growth, while presenting significant reduction in colony formation capacity and increased apoptosis rates. Moreover, strong G2/M arrest was detected suggesting important impaired proliferation after treatment. CONCLUSIONS: PLK1 mRNA expression level is not associated with prognosis in childhood ALL; however, considering the great variability observed in the sample and the in vitro experiments presented herein, BI 2536 treatment might serve as a promising therapeutic to enhance the efficacy of conventional treatment modalities in some childhood ALL cases.

Asunto(s)

Proteínas de Ciclo Celular , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas , Pteridinas/farmacología , Adolescente , Médula Ósea/metabolismo , Médula Ósea/patología , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/biosíntesis , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Lactante , Células Jurkat , Puntos de Control de la Fase M del Ciclo Celular/efectos de los fármacos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/biosíntesis , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/biosíntesis , ARN Mensajero/biosíntesis , ARN Neoplásico/biosíntesis , Estudios Retrospectivos , Tasa de Supervivencia , Quinasa Tipo Polo 1

RESUMEN

Cadherins are cell-to-cell adhesion molecules that play an important role in the establishment of adherent-type junctions by mediating calcium-dependent cellular interactions. The CDH1 gene encodes the transmembrane glycoprotein E-cadherin which is important in maintaining homophilic cell-cell adhesion in epithelial tissues. E-cadherin interacts with catenin proteins to maintain tissue architecture. Structural defects or loss of expression of E-cadherin have been reported as a common feature in several human cancer types. This study aimed to evaluate the expression of E-cadherin and their correlation with clinical features in microdissected brain tumor samples from 81 patients, divided into 62 astrocytic tumors grades I to IV and 19 medulloblastomas, and from 5 white matter non-neoplasic brain tissue samples. E-cadherin (CDH1) gene expression was analyzed by quantitative real-time polymerase chain reaction. Mann-Whitney, Kruskal-Wallis, Kaplan-Meir, and log-rank tests were performed for statistical analyses. We observed a decrease in expression among pathological grades of neuroepithelial tumors. Non-neoplasic brain tissue showed a higher expression level of CDH1 gene than did neuroepithelial tumors. Expression of E-cadherin gene was higher in astrocytic than embryonal tumors (P = 0.0168). Low-grade malignancy astrocytomas (grades I-II) showed higher CDH1 expression than did high-grade malignancy astrocytomas (grades III-IV) and medulloblastomas (P < 0.0001). Non-neoplasic brain tissue showed a higher expression level of CDH1 gene than grade I malignancy astrocytomas, considered as benign tumors (P = 0.0473). These results suggest that a decrease in E-cadherin gene expression level in high-grade neuroepithelial tumors may be a hallmark of malignancy in dedifferentiated tumors and that it may be possibly correlated with their progression and dissemination.

Asunto(s)

Cadherinas/genética , Perfilación de la Expresión Génica , Neoplasias Neuroepiteliales/genética , Adolescente , Adulto , Encéfalo/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Persona de Mediana Edad , Neoplasias Neuroepiteliales/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa

RESUMEN

Cadherins are cell-to-cell adhesion molecules that play an important role in the establishment of adherent-type junctions by mediating calcium-dependent cellular interactions. The CDH1 gene encodes the transmembrane glycoprotein E-cadherin which is important in maintaining homophilic cell-cell adhesion in epithelial tissues. E-cadherin interacts with catenin proteins to maintain tissue architecture. Structural defects or loss of expression of E-cadherin have been reported as a common feature in several human cancer types. This study aimed to evaluate the expression of E-cadherin and their correlation with clinical features in microdissected brain tumor samples from 81 patients, divided into 62 astrocytic tumors grades I to IV and 19 medulloblastomas, and from 5 white matter non-neoplasic brain tissue samples. E-cadherin (CDH1) gene expression was analyzed by quantitative real-time polymerase chain reaction. Mann-Whitney, Kruskal-Wallis, Kaplan-Meir, and log-rank tests were performed for statistical analyses. We observed a decrease in expression among pathological grades of neuroepithelial tumors. Non-neoplasic brain tissue showed a higher expression level of CDH1 gene than did neuroepithelial tumors. Expression of E-cadherin gene was higher in astrocytic than embryonal tumors (P = 0.0168). Low-grade malignancy astrocytomas (grades I-II) showed higher CDH1 expression than did high-grade malignancy astrocytomas (grades III-IV) and medulloblastomas (P < 0.0001). Non-neoplasic brain tissue showed a higher expression level of CDH1 gene than grade I malignancy astrocytomas, considered as benign tumors (P = 0.0473). These results suggest that a decrease in E-cadherin gene expression level in high-grade neuroepithelial tumors may be a hallmark of malignancy in dedifferentiated tumors and that it may be possibly correlated with their progression and dissemination.

Asunto(s)

Humanos , Adolescente , Adulto , Persona de Mediana Edad , Cadherinas/genética , Perfilación de la Expresión Génica , Neoplasias Neuroepiteliales/genética , Cerebro/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Neuroepiteliales/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ARN Mensajero/genética , ARN Mensajero/metabolismo

RESUMEN

The increase in non-communicable chronic diseases of adults is due to demographic changes and changes in the risk factors related to physical activity, smoking habits and nutrition. We describe the methodology for the evaluation of persons at 23/25 years of age of a cohort of individuals born in Ribeirão Preto in 1978/79. We present their socioeconomic characteristics and the profile of some risk factors for chronic diseases. A total of 2063 participants were evaluated by means of blood collection, standardized questionnaires, anthropometric and blood pressure measurements, and methacholine bronchoprovocation tests. The sexes were compared by the chi-square test, with alpha = 0.05. Obesity was similar among men and women (12.8 and 11.1%); overweight was almost double in men (30.3 vs 17.7%). Weight deficit was higher among women than among men (8.6 and 2.6%). Women were more sedentary and consumed less alcohol and tobacco. Dietary fat consumption was similar between sexes, with 63% consuming large amounts (30 to 39.9 g/day). Metabolic syndrome was twice more frequent among men than women (10.7 vs 4.8%), hypertension was six times more frequent (40.9 vs 6.4%); altered triglyceride (16.1 vs 9.8%) and LDL proportions (5.4 vs 2.7%) were also higher in men, while women had a higher percentage of low HDL (44.7 vs 39.5%). Asthma and bronchial hyper-responsiveness were 1.7 and 1.5 times more frequent, respectively, among women. The high prevalence of some risk factors for chronic diseases among young adults supports the need for investments in their prevention.

Asunto(s)

Enfermedad Crónica/epidemiología , Adulto , Asma/epidemiología , Brasil , Métodos Epidemiológicos , Femenino , Humanos , Hipertensión/epidemiología , Estilo de Vida , Masculino , Síndrome Metabólico/epidemiología , Obesidad/epidemiología , Factores Sexuales , Factores Socioeconómicos

RESUMEN

The increase in non-communicable chronic diseases of adults is due to demographic changes and changes in the risk factors related to physical activity, smoking habits and nutrition. We describe the methodology for the evaluation of persons at 23/25 years of age of a cohort of individuals born in Ribeirão Preto in 1978/79. We present their socioeconomic characteristics and the profile of some risk factors for chronic diseases. A total of 2063 participants were evaluated by means of blood collection, standardized questionnaires, anthropometric and blood pressure measurements, and methacholine bronchoprovocation tests. The sexes were compared by the chi-square test, with alpha = 0.05. Obesity was similar among men and women (12.8 and 11.1 percent); overweight was almost double in men (30.3 vs 17.7 percent). Weight deficit was higher among women than among men (8.6 and 2.6 percent). Women were more sedentary and consumed less alcohol and tobacco. Dietary fat consumption was similar between sexes, with 63 percent consuming large amounts (30 to 39.9 g/day). Metabolic syndrome was twice more frequent among men than women (10.7 vs 4.8 percent), hypertension was six times more frequent (40.9 vs 6.4 percent); altered triglyceride (16.1 vs 9.8 percent) and LDL proportions (5.4 vs 2.7 percent) were also higher in men, while women had a higher percentage of low HDL (44.7 vs 39.5 percent). Asthma and bronchial hyper-responsiveness were 1.7 and 1.5 times more frequent, respectively, among women. The high prevalence of some risk factors for chronic diseases among young adults supports the need for investments in their prevention.

Asunto(s)

Adulto , Femenino , Humanos , Masculino , Enfermedad Crónica/epidemiología , Asma/epidemiología , Brasil , Métodos Epidemiológicos , Hipertensión/epidemiología , Estilo de Vida , Síndrome Metabólico/epidemiología , Obesidad/epidemiología , Factores Sexuales , Factores Socioeconómicos

RESUMEN

The human immunoglobulin lambda variable 8 (IGLV8) subgroup is a gene family containing three members, one of them included in a monomorphic 3.7-kb EcoRI genomic fragment located at the major lambda variable locus on chromosome 22q11.1 (gene IGLV8a, EMBL accession No. Z73650) at 100 percent frequency in the normal urban population. The second is a polymorphic RFLP allele included in a 6.0-kb EcoRI fragment at 10 percent frequency, and the third is located in a monomorphic 8.0-kb EcoRI fragment at 100 percent frequency, the last being translocated to chromosome 8q11.2 and considered to be an orphan gene. Our Southern blot-EcoRI-RFLP studies in normal individuals and in patients with rheumatoid arthritis (RA) or with systemic lupus erythematosus (SLE), using a specific probe for the IGLV8 gene family (probe pVL8, EMBL accession No. X75424), have revealed the two monomorphic genomic fragments containing the IGLV8 genes, i.e., the 3.7-kb fragment from chromosome 22q11.1 and the 8.0-kb fragment from 8q11.2, both occurring at 100 percent frequency (103 normal individuals, 48 RA and 28 SLE patients analyzed), but absence of the 6.0-kb IGLV8 polymorphic RFLP allele in all RA or SLE patients. As expected, the frequency of the 6.0-kb allele among the normal individuals was 10 percent. These findings suggest an association between the absence of the 6.0-kb EcoRI fragment and rheumatoid arthritis and systemic lupus erythematosus

Asunto(s)

Humanos , Masculino , Femenino , Artritis Reumatoide/genética , Desoxirribonucleasa EcoRI/genética , Cadenas lambda de Inmunoglobulina/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo de Longitud del Fragmento de Restricción , Alelos , Southern Blotting , Cromosomas Humanos Par 22/genética , Cromosomas Humanos Par 8/genética