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1.
Pharmacogenomics J ; 18(2): 270-274, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28534526

RESUMEN

Neutropenia and infection are major dose-limiting side effects of chemotherapy. The risk of initial infection and subsequent complications are directly related to the depth and duration of neutropenia. Recent genome-wide association studies identified variants in DARC and CXCL2 genes, and in ORMDL3-GSDMA-CSF3 locus on chromosome 17q21 that influence white blood cell and neutrophil counts in healthy individuals. To investigate whether polymorphisms in these loci in conjunction with chemotherapy may modulate risk of treatment complications, we analyzed 21 SNPs across these genes for an association with chemotherapy-related neutropenia and infection in 286 Caucasian children with acute lymphoblastic leukemia. After correction for multiple testing, DARC polymorphism rs3027012 in 5'-UTR was associated with higher risk of low absolute phagocyte count (APC<500 and <1000 cells per microliter, P=0.001 and P<0.0005, respectively) and hospitalization due to febrile neutropenia (P=0.002). Protective effect was instead seen for DARC rs12075 A to G substitution (P=0.004). The SNP rs3859192 in the GSDMA were associated with hospitalization due to infection (P=0.004); infection was also modulated in the additive manner by the CXCL2 rs16850408 (P=0.002). This study shows for the first time that the variations in DARC, GSDMA and CXCL2 genes may play a role in the onset of chemotherapy complications.


Asunto(s)
Antineoplásicos/efectos adversos , Neutropenia/genética , Polimorfismo de Nucleótido Simple/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Antineoplásicos/sangre , Quimiocina CXCL2/genética , Niño , Sistema del Grupo Sanguíneo Duffy/genética , Humanos , Recuento de Leucocitos/tendencias , Proteínas de Neoplasias/genética , Neutropenia/sangre , Neutropenia/inducido químicamente , Neutrófilos/efectos de los fármacos , Neutrófilos/fisiología , Variantes Farmacogenómicas/efectos de los fármacos , Variantes Farmacogenómicas/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Receptores de Superficie Celular/genética
2.
Pediatr Blood Cancer ; 65(5): e26938, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29334169

RESUMEN

BACKGROUND: Children with acute lymphoblastic leukemia (ALL) have increased risk of thromboembolism (TE). However, the predictors of ALL-associated TE are as yet uncertain. OBJECTIVE: This exploratory, prospective cohort study evaluated the effects of clinical (age, gender, ALL risk group) and laboratory variables (hematological parameters, ABO blood group, inherited and acquired prothrombotic defects [PDs]) at diagnosis on the development of symptomatic TE (sTE) in children (aged 1 to ≤18) treated on the Dana-Farber Cancer Institute ALL 05-001 study. PROCEDURES: Samples collected prior to the start of ALL therapy were evaluated for genetic and acquired PDs (proteins C and S, antithrombin, procoagulant factors VIII (FVIII:C), IX, XI and von Willebrand factor antigen levels, gene polymorphisms of factor V G1691A, prothrombin gene G20210A and methylene tetrahydrofolate reductase C677T, anticardiolipin antibodies, fasting lipoprotein(a), and homocysteine). RESULTS: Of 131 enrolled patients (mean age [range] 6.4 [1-17] years) 70 were male patients and 20 patients (15%) developed sTE. Acquired or inherited PD had no impact on the risk of sTE. Multivariable analyses identified older age (odds ratio [OR] 1.13; 95% confidence interval [CI]: 1.01, 1.26) and non-O blood group (OR 3.64, 95% CI: 1.06, 12.51) as independent predictors for development of sTE. Patients with circulating blasts had higher odds of developing sTE (OR 6.66; 95% CI: 0.82, 53.85). CONCLUSION: Older age, non-O blood group, and presence of circulating blasts, but not PDs, predicted the risk of sTE during ALL therapy. We recommend evaluation of these novel risk factors in the development of ALL-associated TE. If confirmed, these easily accessible variables at diagnosis can help develop a risk-prediction model for ALL-associated TE.


Asunto(s)
Biomarcadores/análisis , Terapia Combinada/efectos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Trombosis/diagnóstico , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Proyectos Piloto , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Trombosis/etiología , Trombosis/metabolismo
3.
Pediatr Blood Cancer ; 65(5): e26952, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29319209

RESUMEN

BACKGROUND: Pediatric patients receiving induction chemotherapy for newly diagnosed acute lymphoblastic leukemia (ALL) are at high risk of developing life-threatening infections. We investigated whether uniform antibacterial guidelines, including mandatory antibacterial prophylaxis in afebrile patients during induction, decreases the incidence of microbiologically documented bacteremia. METHODS: Between 2012 and 2015, 230 patients with newly diagnosed ALL (aged 1-21) were enrolled on Dana-Farber Cancer Institute ALL Consortium Protocol 11-001 (DFCI 11-001). Induction therapy, regardless of risk group, included vincristine, prednisone, doxorubicin, methotrexate, and PEG-asparaginase. Afebrile patients received fluoroquinolone prophylaxis at the initiation of induction and those presenting with fever received broad-spectrum antibiotics; antibiotics were continued until blood count recovery. Rates of documented bacteremias and fungal infections on DFCI 11-001 were compared to those on the predecessor protocol (DFCI 05-001), which included the same induction phase without antibiotic prophylaxis guidelines. RESULTS: Sixty-six (28.7%) patients received fluoroquinolone prophylaxis, the remaining patients received broad-spectrum antibiotics. Twenty-four (36.4%) patients on prophylaxis developed fever and seven (10.6%) developed bacteremia. The overall rate of infection during induction on DFCI 11-001 was lower than on DFCl 05-001 (14.3% vs. 26.3%, P < 0.0001) due to a decreased rate of bacteremia (10.9% vs. 24.4%, P < 0.0001). The rate of fungal infections (4.8% vs. 3.6%) and induction death (0.9% vs. 2%) was not significantly different. CONCLUSION: For children with newly diagnosed ALL, uniform antibiotic administration until blood count recovery, including fluoroquinolone prophylaxis for afebrile patients, reduced the incidence of bacteremia during the induction phase. Larger, randomized studies should be performed to confirm these findings.


Asunto(s)
Profilaxis Antibiótica , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bacteriemia/prevención & control , Quimioterapia de Inducción/efectos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adolescente , Adulto , Asparaginasa/administración & dosificación , Bacteriemia/inducido químicamente , Bacteriemia/microbiología , Niño , Preescolar , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Metotrexato/administración & dosificación , Polietilenglicoles/administración & dosificación , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Prednisona/administración & dosificación , Pronóstico , Tasa de Supervivencia , Vincristina/administración & dosificación , Adulto Joven
4.
Indoor Air ; 25(6): 582-97, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25603837

RESUMEN

UNLABELLED: A randomized controlled trial was carried out to measure the impact of an intervention on ventilation, indoor air contaminants, and asthma symptoms of children. Eighty-three asthmatic children living in low-ventilated homes were followed over 2 years. Several environmental parameters were measured during the summer, fall, and winter. The children were randomized after Year 1 (43 Intervention; 40 Control). The intervention included the installation of either a Heat Recovery Ventilator (HRV) or Energy Recovery Ventilator (ERV). During the fall and winter seasons, there was a significant increase in the mean ventilation rate in the homes of the intervention group. A statistically significant reduction in mean formaldehyde, airborne mold spores, toluene, styrene, limonene, and α-pinene concentrations was observed in the intervention group. There was no significant group difference in change in the number of days with symptoms per 14 days. However, there was a significant decrease in the proportion of children who experienced any wheezing (≥1 episode) and those with ≥4 episodes in the 12-month period in the intervention group. This study indicates that improved ventilation reduces air contaminants and may prevent wheezing. Due to lack of power, a bigger study is needed. PRACTICAL IMPLICATIONS: Positive findings from this study include the fact that, upon recruitment, most of the single family homes with asthmatic children were already equipped with a mechanical ventilation system and had relatively good indoor air quality. However, the 8-h indoor guideline for formaldehyde (50 µg/m3) was frequently exceeded and the ventilation rates were low in most of the homes, even those with a ventilation system. Both ERVs and HRVs were equally effective at increasing air exchange rates above 0.30 ACH and at preventing formaldehyde concentrations from exceeding the 50 µg/m3 guideline during the fall and winter seasons. Furthermore, the ERVs were effective at preventing excessively low relative humidities in the homes. Based on observed difference of risk, intervention to increase ventilation in five sample homes and children would prevent 1 home to exceed the indoor air long-term formaldehyde guideline and prevent 1 asthmatic child experiencing at least one episode of wheezing over a year.


Asunto(s)
Contaminación del Aire Interior/prevención & control , Asma/prevención & control , Ventilación , Contaminantes Atmosféricos/análisis , Asma/fisiopatología , Niño , Preescolar , Femenino , Humanos , Masculino , Ruidos Respiratorios
5.
Intern Med J ; 42(3): 260-6, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21118414

RESUMEN

BACKGROUND: Recent data suggest that masked hypertension (MH) carries a cardiovascular risk similar to that of uncontrolled hypertension. AIMS: The objective of this study was to determine the prevalence and determinants of MH in patients treated for hypertension in a Canadian primary care setting. METHODS: Office blood pressure (OBP) was measured at baseline and after 3 months of valsartan-based therapy in 5636 hypertensive patients who had recorded their home blood pressure monitoring (HBPM) for seven consecutive days at month 3 using an Omron HEM-711 apparatus. MH was defined in nondiabetic patients as an OBP <140/90 mmHg and an HBPM ≥135/85 mmHg, and in those with diabetes as an OBP <130/80 mmHg and an HBPM ≥125/75 mmHg. RESULTS: Of the 5636 patients, 1025 had diabetes. OBP was controlled at 3 months in 268 (26.1%) of them, but 167 (62.3%) had MH. OBP was controlled in 2728 (59.1%) of the 4611 patients without diabetes, and 935 (34.3%) of them had MH. Overall, 1102 patients had MH, representing 36.8% of patients with controlled OBP and 19.6% of the entire hypertensive study population. Stepwise multiple logistic regression analysis in nondiabetic patients with controlled OBP at 3 months revealed that older age, male sex, higher body mass index and higher office systolic blood pressure were determinants of MH. CONCLUSION: Our results indicate that one of five hypertensive patients and more than one of three with controlled OBP will have MH. MH is associated with other cardiovascular risk factors, such as diabetes, and in nondiabetics, with male sex, older age and obesity.


Asunto(s)
Hipertensión Enmascarada/epidemiología , Atención Primaria de Salud , Antagonistas Adrenérgicos beta/administración & dosificación , Antagonistas Adrenérgicos beta/uso terapéutico , Anciano , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Antihipertensivos/administración & dosificación , Antihipertensivos/uso terapéutico , Monitoreo Ambulatorio de la Presión Arterial , Enfermedades Cardiovasculares/epidemiología , Comorbilidad , Complicaciones de la Diabetes/epidemiología , Quimioterapia Combinada , Dislipidemias/epidemiología , Femenino , Insuficiencia Cardíaca/epidemiología , Humanos , Hidroclorotiazida/administración & dosificación , Hidroclorotiazida/uso terapéutico , Hipertensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Prevalencia , Quebec/epidemiología , Riesgo , Tetrazoles/administración & dosificación , Tetrazoles/uso terapéutico , Valina/administración & dosificación , Valina/análogos & derivados , Valina/uso terapéutico , Valsartán , Hipertensión de la Bata Blanca/epidemiología
6.
J Natl Cancer Inst ; 86(22): 1707-10, 1994 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-7966399

RESUMEN

BACKGROUND: Adrenocortical carcinoma (ADCC) is a rare childhood cancer, affecting three of 1 million children younger than 16 years old in the United States. ADCC may be found in association with the Li-Fraumeni and Beckwith-Wiedemann syndromes. Children with ADCC are also at substantially increased risk of second primary cancers. Because of these associations, it is believed that the genetic basis for ADCC is stronger than for most childhood malignancies. Germline mutations of the TP53 tumor suppressor gene are associated with cancer predisposition in families with the Li-Fraumeni syndrome as well as in individuals with sporadically occurring component tumors of the syndrome. PURPOSE: We investigated the possibility that germline TP53 gene alterations existed in children with ADCC. METHODS: Sixteen children with ADCC under the age of 18 were identified from searches of medial oncology records at three Canadian hospitals. Eleven of these 16 patients identified were alive. The mean age at diagnosis was 4.8 years (range, 1-17 years). Family histories were obtained for 11 unselected children with ADCC (six girls and five boys). Pathologic confirmation of tumor diagnosis was obtained from the medical records. Using single-strand conformational polymorphism analysis followed by single-strand DNA sequencing, genomic DNA extracted from whole blood was analyzed for the presence of TP53 mutations for six living ADCC patients. RESULTS: Three of six (50%) children were found to carry germline TP53 mutations in exons 5, 6, and 7, respectively. Both wild-type and mutant alleles were identified in all three TP53 sequences, indicating that the patients were heterozygous for germline TP53 mutations. None of these children was from a family with the Li-Fraumeni syndrome. The mutation in one child was shown to be inherited from the mother, who subsequently developed breast cancer. A striking excess of cancer was found in one family of a patient carrying wild-type TP53. CONCLUSIONS: Our observation of a high frequency of germline TP53 mutations in children with sporadic ADCC suggests that these children may represent probands with which to ascertain Li-Fraumeni syndrome families. It may be reasonable for children with adrenocortical carcinoma to be candidates for germline TP53 analysis. In light of the wealth of information in the Li-Fraumeni literature that associates germline TP53 mutations with a variety of malignancies, this testing may have important consequences for risk assessment for other close relatives, including early-onset breast cancer in the mothers.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/genética , Genes p53/genética , Mutación de Línea Germinal , Adolescente , Secuencia de Bases , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Datos de Secuencia Molecular
7.
Cancer Res ; 45(8): 3522-8, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2410096

RESUMEN

1-beta-D-Arabinofuranosyl-5-azacytosine (ara-5-aza-Cyd) had potent cytotoxicity against human T-type lymphoblastic cells in culture. When Molt-4 cells were exposed to ara-5-aza-Cyd for 24 h, clonogenic survival was reduced by 50 and 98% at initial concentrations of 10(-7) and 10(-6) M, respectively, compared to 3 X 10(-8) and 10(-6) M, respectively, for the same effect with 1-beta-D-arabinofuranosylcytosine (ara-C). The analogue is chemically unstable, with a t1/2 of 12 h at 37 degrees C in phosphate-buffered saline. ara-5-aza-Cyd is not significantly deaminated by human Cyd-deoxycytidine (dCyd) deaminase, in contrast to ara-C. It is phosphorylated by human cytoplasmic dCyd kinase, with a Km of 55 microM and a relative Vmax of 310% compared to dCyd. The primary metabolite (70%) in Molt-4 cells was identified as ara-5-aza-Cyd triphosphate. Thymidine but not uridine or amino acid incorporation was inhibited by ara-5-aza-Cyd. ara-5-aza-Cyd was incorporated in a dose-dependent manner into DNA, but not RNA, primarily in internucleotide linkage as the original compound. Incorporation into the cellular methanol-insoluble fraction was 3- to 5-fold higher at 8 h than was ara-C incorporation. ara-5-aza-Cyd may have a unique activity against tumor cells resistant to ara-C, particularly where high Cyd-dCyd deaminase activity is a factor. The mode of action, like that of ara-C, is probably mediated through its incorporation into DNA and inhibition of DNA synthesis.


Asunto(s)
Antineoplásicos/metabolismo , Azacitidina/metabolismo , ADN/metabolismo , Linfocitos T/metabolismo , Antineoplásicos/farmacología , Células Cultivadas , DCMP Desaminasa/análisis , Desoxicitidina Quinasa/análisis , Estabilidad de Medicamentos , Humanos , Cinética , Estereoisomerismo , Relación Estructura-Actividad , Tritio
8.
Cancer Res ; 53(21): 5269-73, 1993 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8221661

RESUMEN

Neuroblastoma is a common childhood malignancy of the sympathetic nervous system. Mutations in p53, a tumor suppressor gene located on the short arm of chromosome 17, are one of the most common genetic lesions in human cancers. The evidence for trisomies of 17q with loss of 17p in some cases of neuroblastoma led us to consider whether p53 mutations might contribute to the onset and progression of this malignancy. In this study, primary tumors from 38 neuroblastoma patients were screened for mutations within the coding exons of the p53 gene by single-strand conformation polymorphism analysis, and potential mutations were further analyzed by nucleotide sequence analysis. Previously described sequence variations were detected in many of the tumors, including a silent polymorphism at codon 213 (CGA to CGG) and the nontransforming Pro to Arg substitution at codon 72 (CCC to CGC). However, no other sequence variations were detected within the coding portions of the p53 gene. This finding suggests that p53 mutations do not contribute to the etiology of neuroblastoma and that the chromosome 17 alterations observed in neuroblastoma involve genes which are distinct from the p53 locus.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 17 , Genes p53 , Mutación , Neuroblastoma/genética , Trisomía , Secuencia de Bases , Niño , Clonación Molecular , Codón/genética , Cartilla de ADN , Exones , Humanos , Datos de Secuencia Molecular , Estadificación de Neoplasias , Neuroblastoma/patología , Neuroblastoma/cirugía , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo Genético
9.
J Clin Oncol ; 10(2): 323-9, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1732433

RESUMEN

PURPOSE: The purpose of this study was twofold: (1) to provide a population-based estimate of neuroblastoma incidence, disease stage and age distribution, and survival and mortality rates in North America; and (2) to compare these figures in the province of Quebec at a time shortly before the institution of province-wide screening with those in a population-based control group, the Greater Delaware Valley (GDV) Pediatric Tumor Registry. MATERIALS AND METHODS: In Quebec, the four major pediatric teaching hospital records were searched for children with a diagnosis of neuroblastoma. Tumor board registry data and information supplied to the Division of Vital Statistics were also reviewed. Birth statistics were obtained from the population registry. The GDV Pediatric Tumor Registry is a population-based registry of pediatric cancer covering all of Delaware and parts of New Jersey, Pennsylvania, and Maryland. Age, stage of disease, and follow-up data were obtained through December 31, 1989, with Evans neuroblastoma staging data used for all comparisons. RESULTS: One hundred thirty children with neuroblastoma were identified in Quebec and 165 in the GDV, in a combined population of 3,178,736 children. The annual incidence of neuroblastoma was 10.95/10(6) under the age of 15 years and 27.75/10(6) between the ages of 0 and 4 years. The annual mortality rate due to neuroblastoma was 4.89/10(6) and 9.10/10(6) for the age groups 0 to 14 and 0 to 4, respectively. The overall 10-year survival rate for the 295 cases of neuroblastoma was 55%. The 10-year survival rates for patients with Evans stage I-IV and IVS disease were 88%, 90%, 63%, 21%, and 81%. There was no significant difference observed in the incidence, mortality, or survival in the two populations. CONCLUSION: These data represent the first large, population-based description of the clinical presentation and outcome of patients with neuroblastoma in North America, with no significant differences noted between Quebec patients and the GDV patients.


Asunto(s)
Neuroblastoma/epidemiología , Adolescente , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Masculino , Tamizaje Masivo , Mid-Atlantic Region/epidemiología , Estadificación de Neoplasias , Neuroblastoma/mortalidad , Neuroblastoma/patología , Quebec/epidemiología , Sistema de Registros , Tasa de Supervivencia
10.
J Clin Oncol ; 8(3): 378-84, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2155307

RESUMEN

Polymorphic B-cell lymphoma seen in four patients with congenital immunodeficiencies and in two patients with leukemia receiving chemotherapy was associated with the Epstein-Barr virus (EBV). The tumors had characteristic histologic features: they were polymorphic consisting of a mixture of lymphoblasts and differentiated cells including plasma cells, and areas of hemorrhagic necrosis were prominent. The tumors were either polyclonal, monoclonal, or multiclonal. Patients with congenital immunodeficiencies who developed these tumors died despite radiotherapy, corticosteroids plus acyclovir, or a combination of intravenous (IV) immunoglobulins and alpha 2 interferon. Patients with leukemia recovered when immunosuppressive drugs were discontinued and leukemia has not recurred over a period of 2 and 4 years, respectively, in the two patients.


Asunto(s)
Neoplasias Encefálicas/complicaciones , Linfoma de Burkitt/complicaciones , Síndromes de Inmunodeficiencia/congénito , Leucemia Linfoide/complicaciones , Antineoplásicos/administración & dosificación , Linfocitos B , Neoplasias Encefálicas/patología , Linfoma de Burkitt/patología , Preescolar , Femenino , Herpesvirus Humano 4 , Humanos , Síndromes de Inmunodeficiencia/complicaciones , Lactante , Leucemia Linfoide/tratamiento farmacológico , Leucemia Linfoide/patología , Masculino
11.
Leukemia ; 11(6): 797-802, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9177430

RESUMEN

Acute lymphoblastic leukemia (ALL) is the most frequent cancer encountered in children. Little is known about the molecular pathology of childhood T cell ALL. Oncogenesis is a multistep process that involves alterations in proto-oncogenes and tumor suppressor genes. Recently, a mutator phenotype detectable by microsatellite instabilities was shown to be associated with predisposition to cancer. This new mechanism for human carcinogenesis is caused by defects in the DNA replication/repair system. To study the involvement of some of these mutational events in the development of T cell ALL, we have initiated a systematic search for losses of heterozygosity (LOH) and microsatellite instabilities in children affected with this disease. These patients were allelotyped by PCR using 56 microsatellite markers located near known or putative tumor suppressor genes. The microsatellite patterns were altered in more than 80% of the patients. LOH were detected in chromosomes 6p, 12p and 9p. Two third of the patients were deleted for chromosome 9p21, suggesting the involvement of a tumor suppressor gene, probably the p16 gene. The only patient refractory to chemotherapy was shown to be associated with a mutator phenotype. This is the first documented case of a childhood neoplasia associated with genomic instabilities. Our results suggest that defects in DNA replication/repair components are involved in the development of a subset of childhood T cell ALL.


Asunto(s)
Deleción Cromosómica , Mapeo Cromosómico , Reordenamiento Génico , Leucemia-Linfoma de Células T del Adulto/genética , Repeticiones de Microsatélite , Adolescente , Secuencia de Bases , Médula Ósea/patología , Niño , Preescolar , Cromosomas Humanos Par 12 , Cromosomas Humanos Par 6 , Cromosomas Humanos Par 9 , Reparación del ADN , Femenino , Reordenamiento Génico de la Cadena delta de los Receptores de Antígenos de los Linfocitos T , Genes de Inmunoglobulinas , Marcadores Genéticos , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Inmunofenotipificación , Lactante , Leucemia-Linfoma de Células T del Adulto/inmunología , Leucemia-Linfoma de Células T del Adulto/patología , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Recurrencia
12.
Eur J Cancer ; 33(12): 2098-100, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9516861

RESUMEN

In contrast to MYCN amplification, expression of either trk-A or CD44 in neuroblastoma is a favourable prognostic factor and were therefore investigated in tumours from 250 patients. One hundred and eleven localised/4s (Group 1) and 139 stage 4 (Group 2) tumours were analysed. MYCN copy number was obtained by Southern blotting or PCR amplification and was detected in 28 stage 4 tumours. Trk-A and CD44 expression was detected by immunoperoxidase staining using murine monoclonal antibodies 5C3 and L178, respectively. Expression was scored as positive (homogeneous), mixed (heterogeneous) or non-reactive (negative). Trk-A expression was found in 95% of Group 1 tumours and 49% of Group 2 tumours. CD44 expression was found in 100% of Group 1 tumours, the majority of which had a strong homogeneous expression. Lack of CD44 expression occurred in 25% of tumours, all stage 4 neuroblastoma. Of the 28 MYCN amplified tumours, 27/28 (96%) were trk-A negative, and 13/28 (46%) CD44 negative. We conclude that (1) a significant percentage of stage 4 neuroblastoma express either or both trk-A and CD44, (2) the absence of CD44 expression is highly restricted to stage 4 neuroblastoma and is associated with the lack of trk-A expression, (3) trk-A negativity among CD44-positive tumours is associated with stage 4 neuroblastoma and (4) the absence of trk-A expression is highly correlated with MYCN amplification.


Asunto(s)
Proteínas Portadoras/metabolismo , Ganglioneuroma/genética , Ganglioneuroma/metabolismo , Amplificación de Genes , Genes myc/genética , Receptores de Hialuranos/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Neuroblastoma/genética , Neuroblastoma/metabolismo , Receptor trkA , Preescolar , Supervivencia sin Enfermedad , Ganglioneuroma/patología , Humanos , Lactante , Análisis Multivariante , Estadificación de Neoplasias , Neuroblastoma/patología
13.
Eur J Cancer ; 33(12): 2106-12, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9516863

RESUMEN

Neuroblastoma exhibits many characteristics which would suggest that preclinical detection may improve outcome. The Quebec Neuroblastoma Screening Project was initiated to determine whether mass screening could reduce mortality in a large cohort of infants. All 476,603 children born in the province of Quebec during a 5-year period of time (1 May 1989 to 30 April 1994) were eligible for determinations of urinary catecholamine metabolites at 3 weeks and 6 months of age. Children with positive screening were referred to one of four paediatric cancer centres in Quebec for uniform evaluation and treatment. Standardised incidence ratios (SIRs) were calculated for neuroblastoma in Quebec and two comparable population-based controls during the same period of time using similar ascertainment procedures. Compliance with screening in Quebec was 91% at 3 weeks (n = 425,816) and 74% at 6 months (n = 349,706). Up to 31 July 1995 with a follow-up of the birth cohort of 15-75 months, 118 cases of neuroblastoma were diagnosed, 43 detected preclinically by screening, 20 detected clinically prior to screening at 3 weeks of age and 55 detected clinically after 3 weeks of age having normal screens (n = 52) or never screened (n = 3). Based on data from concurrent control populations, 54.5 cases of neuroblastoma would have been expected in Quebec during the study period for an SIR of 2.17 (95% CI 1.79-2.57, P < 0.0001). For the two control groups, the overall SIR was 1.00 (NS). SIRs for Quebec by age at diagnosis in yearly intervals show a marked increased incidence under 1 year of age (SIR = 2.85, 95% CI 2.26-3.50), with no reduction in incidence in subsequent years. We conclude that screening for neuroblastoma markedly increases the incidence in infants without decreasing the incidence of unfavourable advanced stage disease in older children. It is unlikely that screening for neuroblastoma in infants will reduce the mortality of this disease.


Asunto(s)
Tamizaje Masivo , Neuroblastoma/prevención & control , Canadá/epidemiología , Niño , Preescolar , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Recién Nacido , Estadificación de Neoplasias , Neuroblastoma/epidemiología , Neuroblastoma/patología , Cooperación del Paciente
14.
Semin Oncol ; 14(2 Suppl 1): 226-30, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3473678

RESUMEN

Cytotoxicity of arabinofuranosylcytosine (ara-C) has been related in vitro to the inhibition of the DNA polymerase activities by arabinosylcytosine triphosphate (ara-CTP) and the incorporation of ara-C into the DNA where, acting as a chain terminator, it slows the chain elongation. Induced in vitro cellular resistance to ara-C was shown to be secondary to altered deoxycytidine (dCyd) kinase activity, dCyd deaminase activity, or deoxynucleotides triphosphates (dNTP) pools. Recent studies reported no differences of ara-C metabolism in cells obtained from leukemic patients at diagnosis and at relapse after ara-C therapy, suggesting that unknown cellular biochemical determinants may be involved in acquisition of ara-C resistance. Using dialysed crude extracts of leukemic cells obtained from patients at diagnosis, we observed variable inhibition of their DNA polymerase activities by arabinosylcytosine monophosphate (ara-CMP) at 2 mmol/L (0% to 50% inhibition). In similar conditions, ara-CMP reduced the polymerase activities of human thymus extract by 35% and 55% in extract of HL-60 cells (cultured human promyelocytic cells). The ara-CMP factor responsible for inhibition of DNA polymerase activity was nondialysable, heat labile, proteinase K sensitive, and has an estimated molecular mass of 30 kilodalton by gel filtration. After partial purification, this protein had no DNA polymerase RNA polymerase activities. In presence of the regulator and ara-CMP at 2 mmol/L, we observed no inhibition of the HL-60 3'----5' and 5'----3' exonucleases activities, suggesting the regulator interaction being mainly with the DNA polymerases in presence of ara-CMP. The relevance of the presence or absence of this protein regarding the cell sensitivity to ara-C is under investigation.


Asunto(s)
Arabinonucleotidos/farmacología , Citidina Monofosfato/farmacología , Nucleótidos de Citosina/farmacología , ADN Polimerasa II/antagonistas & inhibidores , Proteínas de Unión al ADN/fisiología , Leucemia/fisiopatología , Enfermedad Aguda , Línea Celular , Citidina Monofosfato/análogos & derivados , Citidina Monofosfato/metabolismo , Desoxicitidina Monofosfato/metabolismo , Humanos , Leucemia Mieloide Aguda/enzimología , Peso Molecular , Uridina Monofosfato/metabolismo
15.
Biochem Pharmacol ; 50(10): 1701-9, 1995 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-7503774

RESUMEN

P-glycoprotein (P-gp) is expressed at high levels in a variety of non-cancerous tissues such as the endothelial cells of the blood-brain barrier (BBB) capillaries. These thin capillaries tightly regulate the movement of substrates from the circulating blood into the brain. P-gp may be involved in the exclusion of various drugs from the capillary endothelial cells, blocking their entry into the brain. However, interactions of drugs with P-gp expressed in brain capillaries remain to be characterized. We have performed photoaffinity labeling studies using [125I]arylazidoprazosin (IAAP) to evaluate the inhibitory efficiency of various compounds. Cyclosporin A (CsA) and its derivative PSC 833 (PSC) were the most effective inhibitors of IAAP binding among the drugs tested. The magnitude of inhibition was: PSC > CsA > quinidine > vinblastine > verapamil < actinomycin D > colchicine > reserpine > bilirubin > doxorubicin > progesterone. Cremophor El, the vehicle used to administer CsA and PSC intravenously, was also able to inhibit IAAP photolabeling of P-gp. Labeling experiments were also performed using a photoactivatable [3H]CsA derivative. Photolabeling of P-gp with this compound was abolished almost completely by CsA and PSC. In vivo studies were also performed by treating rats with CsA [10 mg/(kg.day) for 10 days]. Following this treatment, no alteration in the level of P-gp expression in brain capillaries was observed. These results suggest that, at the proper dosage, administration of CsA to cancer patients could help to enhance the response of brain tumors to chemotherapeutic agents without modifying the intrinsic level of P-gp expression in this tissue.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Encéfalo/irrigación sanguínea , Ciclosporina/farmacología , Ciclosporinas/farmacología , Marcadores de Afinidad/metabolismo , Animales , Azidas/antagonistas & inhibidores , Azidas/metabolismo , Capilares/efectos de los fármacos , Capilares/metabolismo , Interacciones Farmacológicas , Glicerol/análogos & derivados , Glicerol/farmacología , Técnicas In Vitro , Radioisótopos de Yodo , Masculino , Prazosina/análogos & derivados , Prazosina/antagonistas & inhibidores , Prazosina/metabolismo , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Tritio
16.
Chronobiol Int ; 10(3): 201-4, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8319318

RESUMEN

The evolution of 118 children treated for acute lymphoblastic leukemia between 1976 and 1984, and followed until 1991, was reviewed. Maintenance chemotherapy consisted of daily 6-mercaptopurine (6-MP), weekly methotrexate (MTX), and monthly vincristine and prednisone. Eighty-two children took 6-MP and MTX in the morning, and 36 took them in the evening. Disease-free survival, as determined by Kaplan-Meier analysis, was better for children on evening chemotherapy. Regression analysis (Cox proportional hazards model, with evening versus morning schedule as exposure variable, and age at diagnosis, leucocytosis at diagnosis, and sex as covariates) showed that for those surviving free of disease for longer than 78 weeks, the risk of relapse was 2.56 times greater for the morning schedule than for the evening one.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Ritmo Circadiano , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Niño , Esquema de Medicación , Estudios de Seguimiento , Humanos , Mercaptopurina/administración & dosificación , Metotrexato/administración & dosificación , Prednisona/administración & dosificación , Modelos de Riesgos Proporcionales , Recurrencia , Análisis de Regresión , Análisis de Supervivencia , Factores de Tiempo , Vincristina/administración & dosificación
17.
J AAPOS ; 1(4): 226-30, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10532768

RESUMEN

INTRODUCTION: Hemangiomas of the orbit and eyelids may cause serious ocular problems usually related to amblyopia and astigmatism. Steroids have become the accepted treatment. However, some hemangiomas are resistant to steroids or require prolonged use,with unacceptable side effects. Interferon alfa-2b, an antiangiogenic protein, was used in this prospective study to treat visually threatening hemangiomas that were unresponsive to oral or intralesional steroid treatment. METHODS: Forty patients aged 2 to 36 months with life- or organ-threatening hemangiomas were prospectively enrolled to evaluate the efficacy and safety of interferon alfa treatment for hemangiomas. Sixteen of these 40 patients had hemangiomas causing serious ocular dysfunction. The patients were treated with 3 x 10(6) U/m2 interferon alfa-2b subcutaneously daily for 3 months; treatment was then tapered or retreated according to response and protocol. Therapeutic responses were documented. RESULTS: Fifteen patients with ocular hemangiomas have finished treatment. The pretreatment volume measured by computed axial tomographywas an average of 22.3 cm3. Clinical response with eye opening was observed at an average of 6 weeks. There was a significant regression of the hemangioma in all patients, with an average 82% reduction in volume. Patients were treated with glasses and occlusion therapy as appropriate. Final visual acuities with a follow-up averaging 14 months after cessation of interferon treatment were normal, except that five of 15 patients had amblyopia; one of these patients had 20/40, two had 20/60, and two had 20/70. There were no major illnesses or serious adverse side effects. CONCLUSION: Interferon alfa-2b treatment resulted in good to excellent regression of all the hemangiomas. This regression was clinically significant,with patients able to open the affected eye an average of 6 weeks into treatment. Visual results were good, with moderate amblyopia occurring only in patients treated at a later age. Interferon alfa-2b was well tolerated by these young patients, and no significant illness or side effect has occurred.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias del Ojo/tratamiento farmacológico , Hemangioma Capilar/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Trastornos de la Visión/prevención & control , Ambliopía/etiología , Preescolar , Neoplasias del Ojo/complicaciones , Neoplasias del Ojo/diagnóstico por imagen , Neoplasias del Ojo/fisiopatología , Anteojos , Párpados/fisiopatología , Femenino , Hemangioma Capilar/complicaciones , Hemangioma Capilar/diagnóstico por imagen , Hemangioma Capilar/fisiopatología , Humanos , Lactante , Recién Nacido , Interferón alfa-2 , Masculino , Apósitos Oclusivos , Estudios Prospectivos , Proteínas Recombinantes , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Trastornos de la Visión/terapia , Agudeza Visual
19.
Contemp Clin Trials ; 32(5): 741-6, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21628001

RESUMEN

BACKGROUND: Zoledronic acid is an intravenous once yearly bisphosphonate that has been shown to be effective and safe in improving BMD (bone mineral density) and reducing fracture risk in controlled clinical trials. IVORY is a Canadian post marketing study aiming at assessing real-life effectiveness, health care resource utilization, safety and compliance to treatment with zoledronic acid in comparison to orally administered bisphosphonates (OBP). METHODS: IVORY is a prospective two cohort observational study of patients treated with zoledronic acid or OBP. Eligible patients are postmenopausal females, >45 years old with osteoporosis for whom initiation of treatment with OBP or zoledronic acid is indicated. Subjects will be followed for four years. Outcomes are the change in lumbar spine, femoral neck and total hip BMD and the incidence of fractures. The study cohort will consist of 920 patients treated with zoledronic acid and 460 treated with OBP. Additional comparisons will be based on external standardization to the population of Quebec patients treated with OBP. DISCUSSION: Post Marketing Observational Studies (PMOS) are essential for the assessment of real-life effectiveness and population based benefit-risk ratios. The effect of access to care, compliance, adherence to guidelines, patient comorbidity and concomitant medication use could only be assessed with observational studies. IVORY will provide information about true life effectiveness, benefit-risk ratios, cost-effectiveness and barriers to the process-outcome optimization. The results will have implications for decision makers and health care stakeholders regarding the management of osteoporosis in Canada.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Servicios de Salud Comunitaria/organización & administración , Difosfonatos/uso terapéutico , Imidazoles/uso terapéutico , Osteoporosis Posmenopáusica/prevención & control , Salud de la Mujer , Análisis de Varianza , Canadá , Distribución de Chi-Cuadrado , Femenino , Humanos , Estudios Multicéntricos como Asunto , Vigilancia de Productos Comercializados/métodos , Estudios Prospectivos , Riesgo , Medición de Riesgo , Encuestas y Cuestionarios , Factores de Tiempo , Ácido Zoledrónico
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