Ewing's sarcoma: Analysis of single nucleotide polymorphism in the EWS gene

AbstractWe aimed to investigate single nucleotide polymorphisms (SNPs) in the EWS gene breaking region in order to analyze Ewing's sarcoma susceptibility. The SNPs were investigated in a healthy subject population and in Ewing's sarcoma patients from Southern Brazil. Genotyping was performed by TaqMan® assay for allelic discrimination using Real-Time PCR. The analysis of incidence of SNPs or different SNP-arrangements revealed a higher presence of homozygote TT-rs4820804 in Ewing's sarcoma patients (p=0.02; Chi Square Test). About 300bp from the rs4820804 SNP lies a palindromic hexamer (5′-GCTAGC-3′) and three nucleotides (GTC), which were previously identified to be in close vicinity of the breakpoint junction in both EWS and FLI1 genes. This DNA segment surrounding the rs4820804 SNP is likely to indicate a breakpoint region. If the T-rs4820804 allele predisposes a DNA fragment to breakage, homozygotes (TT-rs4820804) would have double the chance of having a chromosome break, increasing the chances for a translocation to occur. In conclusion, the TT-rs4820804 EWS genotype can be associated with Ewing's sarcoma and the SNP rs4820804 can be a candidate marker to understand Ewing's sarcoma susceptibility

What is the impact of local control in Ewing sarcoma: analysis of the first Brazilian collaborative study group-EWING1

Background: Relapse in localized Ewing sarcoma patients has been a matter of concern regarding poor prognosis. Therefore, we investigated the impact of local control modality (surgery, surgery plus radiotherapy, and radiotherapy) on clinical outcomes such as survival and recurrence in patients with non-metastatic Ewing sarcoma treated on the first Brazilian Collaborative Group Trial of the Ewing Family of Tumors (EWING1). Methods: Seventy-three patients with localized Ewing sarcoma of bone aged < 30 years were included. The treating physicians defined the modality of local control based on the recommendations of the coordinating center and the patient and tumor characteristics. Possible associations of local control modality with local failure (LF), disease-free survival (DFS), event-free survival (EFS), overall survival (OS), and clinical characteristics were analyzed. Results: Mean patient age was 12.8 years (range, 2 to 25 years) and median follow-up time was 4.5 years (range, 2. 3 to 6.7 years). Forty-seven patients underwent surgery, 13 received radiotherapy, and 13 received both. The 5-year EFS, OS, and DFS for all patients was 62.1%, 63.3%, and 73.1%, respectively. The 5-year cumulative incidence (CI) of LF was 7.6% for surgery, 11.1% for radiotherapy, and 0% for postoperative radiotherapy (PORT) (p = 0.61). The 5-year EFS was 71.7% for surgery, 30.8% for radiotherapy, and 64.1% for PORT (p = 0.009). Conclusions: There was a significant effect of local control modality on EFS and OS in the study. Surgery and PORT modalities yielded very close results. The group treated with radiotherapy alone had considerably worse outcomes. This may be confounded by greater risk factors in these patients. There was no significant effect of local control modality on the CI of LF and DFS.Children's Cancer InstituteRafael Accordi Foundation, Porto Alegre, RS, BrazilHCPA, Serv Orthoped & Traumatol, Rua Ramiro Barcelos 2350, BR-90035903 Porto Alegre, RS, BrazilUniv Fed Rio Grande do Sul, HCPA, Dept Pediat, Porto Alegre, RS, BrazilPontificia Univ Catolica Rio Grande Sul PUCRS, Dept Pediat, Hosp Sao Lucas, Porto Alegre, RS, BrazilHCPA, Serv Orthoped & Traumatol, Porto Alegre, RS, BrazilUniv Fed Sao Paulo UNIFESP, Support Grp Children & Adolescents Canc GRAACC, Sao Paulo, SP, BrazilHosp Canc Infantojuvenil, Fundacao Pio 12, Barretos, SP, BrazilCtr Hosp Pereira Rossell, Montevideo, UruguayHosp AC Camargo Canc Ctr, Orthoped Serv, Sao Paulo, SP, BrazilSanta Casa Misericordia Porto Alegre, Serv Orthoped & Traumatol, Porto Alegre, RS, BrazilUniv Sao Paulo, Orthoped Trauma Inst, Hosp Clin Sao Paulo, Sch Med, Sao Paulo, SP, BrazilSanta Casa Misericordia Sao Paulo HSCSP, Dept Orthoped & Traumatol, Sao Paulo, SP, BrazilPontificia Univ Catolica Rio Grande Sul PUCRS, Hosp Sao Lucas, Serv Orthoped & Traumatol, Porto Alegre, RS, BrazilUniv Estadual Paulista UNESP, Hosp Clin Botucatu, Sch Med, Botucatu, SP, BrazilInst Canc Infantil, Porto Alegre, RS, BrazilUniv Fed Sao Paulo UNIFESP, Support Grp Children & Adolescents Canc GRAACC, Sao Paulo, SP, BrazilChildren's Cancer InstituteRafael Accordi Foundation, Porto Alegre, RS, BrazilWeb of Scienc

Oncogenic functions of ZEB1 in pediatric solid cancers: interplays with microRNAs and long noncoding RNAs

The transcription factor Zinc finger E-box binding 1 (ZEB1) displays a range of regulatory activities in cell function and embryonic development, including driving epithelial-mesenchymal transition. Several aspects of ZEB1 function can be regulated by its functional interactions with noncoding RNA types, namely microRNAs (miRNAs) and long noncoding RNAs (lncRNAs). Increasing evidence indicates that ZEB1 importantly influences cancer initiation, tumor progression, metastasis, and resistance to treatment. Cancer is the main disease-related cause of death in children and adolescents. Although the role of ZEB1 in pediatric cancer is still poorly understood, emerging findings have shown that it is expressed and regulates childhood solid tumors including osteosarcoma, retinoblastoma, neuroblastoma, and central nervous system tumors. Here, we review the evidence supporting a role for ZEB1, and its interplays with miRNAs and lncRNAs, in pediatric cancers

Clinical and epidemiological analysis of bone marrow transplantation in a pediatric oncology unit

Objetivos: Descrever o perfil e as complicações agudas mais importantes das crianças que receberam transplante de medula óssea no serviço de oncologia pediátrica do Hospital de Clínicas de Porto Alegre. Casuística e métodos: Análise retrospectiva de 41 pacientes, menores de 21 anos, transplantados entre agosto de 1997 até junho de 2002. Deste total, 20 pacientes receberam transplante alogênico, e 21 transplante autogênico. Resultados: No transplante de medula óssea alogênico, a média de idade foi de 8,9 + 5,4 anos, sendo 12 pacientes do sexo masculino. As fontes de células foram: medula óssea, 12; sangue periférico, 5; e sangue de cordão umbilical não aparentado, 3. As doenças tratadas foram: leucemia linfóide aguda em 7 pacientes, leucemia mielóide crônica em 2, leucemia mielóide aguda em 4, síndrome mielodisplásica em 2, linfoma de Burkitt em 1, anemia aplástica grave em 1, anemia de Fanconi em 1, síndrome Chediak-Higashi em 1, e imunodeficiência congênita combinada grave em 1. Um paciente desenvolveu doença do enxerto contra hospedeiro aguda grau 2, três pacientes grau 4, e outros três desenvolveram doença do enxerto contra hospedeiro crônica. Todos haviam recebido sangue periférico como fonte de células. A sobrevida global aos 4 anos foi de 70,0 + 10,3%. A principal causa do óbito foi doença do enxerto contra hospedeiro, em três pacientes, e sepse, em outros três. Todos os óbitos ocorreram antes do centésimo dia. Um dos pacientes que recebeu sangue de cordão umbilical não aparentado está vivo, em bom estado e sem uso de medicações 3 anos e 6 meses pós-transplante. No transplante de medula óssea autogênico, a média de idade foi de 8,7 + 4,3 anos, sendo 11 pacientes do sexo masculino. As fontes de células foram: sangue periférico, 16; medula óssea, 3; sangue periférico mais medula óssea, 2. As doenças tratadas foram: tumor de Wilms em 5 pacientes, tumores da família do sarcoma de Ewing em 4, neuroblastomas em 3, linfomas de Hodgkin em 3, rabdomiossarcomas em 2, tumor neuroectodérmico primitivo do sistema nervoso central em 2, linfoma não-Hodgkin em 1, e leucemia mielóide aguda em 1 paciente. A sobrevida global aos 4 anos está em 59,4 + 11,7%. Cinco óbitos tiveram como causa a progressão da doença de base, um óbito ocorreu devido à infecção 20 meses pós-transplante, e dois óbitos foram precoces por sepse. As toxicidades mais comuns em ambos os grupos foram vômitos, mucosite, diarréia e dor abdominal. Infecções foram documentadas em 58,5% dos pacientes, e 46,9% tiveram no mínimo um agente isolado na hemocultura. O tempo de enxertia de neutrófilos e plaquetas correlacionou-se com o número de células progenitoras infundidas. Conclusão: A sobrevida de nossos pacientes é semelhante à encontrada na literatura de outros serviços nacionais e internacionais. Não encontramos diferença entre os dois tipos de transplante com relação às toxicidades agudas e às infecções.Objectives: To describe the demographics and the most important acute clinical complications in patients undergoing bone marrow transplantation in the Pediatric Oncology Unit at Hospital de Clínicas de Porto Alegre, Brazil. Material and methods: A retrospective analysis was performed including 41 patients treated between August 1997 and June 2002. Twenty patients received allogeneic transplants (AG) and 21 received autologous transplants (AT). Results: The mean age of AG patients was 8.9 + 5.4 years. Twelve patients were male. Stem cell sources were: bone marrow in 12 patients; peripheral blood in 5; and unrelated cord blood in 3. The diseases were acute lymphoid leukemia in 7 patients; acute myeloid leukemia in 4; chronic myeloid leukemia in 2; myelodysplastic syndrome in 2; Burkitt’s lymphoma in 1; severe combined immunodeficiency in 1; Chediaki-Higashi syndrome in 1; Fanconi anemia in 1; and aplastic anemia in 1. One patient developed grade II acute graft-versus-host-disease (GVHD), and three patients had grade IV GVHD. Three patients developed chronic GVHD. In all of them, the cell source was peripheral blood. Survival in this group was 70.0 + 10.3%. The main cause of death was GVHD in three patients and sepsis in another three. All deaths occurred before day 100. One of the patients who received unrelated cord blood is alive 3.5 years after the transplantation. In AG patients, mean age was 8.7 + 4.3 years. Eleven patients were male. The stem cell sources were: peripheral blood in 16; bone marrow in 3; and peripheral blood + bone marrow in 2. The diseases were: Wilms’ tumor in 5 patients; Ewing’s sarcoma family tumors in 4; neuroblastoma in 3; Hodgkin’s disease in 3; non-Hodgkin’s lymphoma in 1; rhabdomyosarcoma in 2; neuroectodermic tumor of the central nervous system in 2; acute myeloid leukemia in 1. Survival in this group was 59.4 + 11.7%. Five patients died due to tumor relapse, 2 patients due to sepsis and one patient died in remission 20 months after bone marrow transplantation due to infection. In the whole group, the most common toxicities were vomiting, mucositis, diarrhea and abdominal pain. Infections were recorded in 58.5% of the patients. In 46.9%, at least one pathogen was isolated in the blood culture. The time required for neutrophil and platelet engraftment was correlated to the number of hematopoietic stem cell infused. Conclusion: The overall survival in our patients is similar to that reported in the literature. We did not find differences between AT and AG patients regarding acute toxicities and infections

Neurotrophin signaling in medulloblastoma

Neurotrophins are a family of secreted proteins that act by binding to tropomyosin receptor kinase (Trk) or p75NTR receptors to regulate nervous system development and plasticity. Increasing evidence indicates that neurotrophins and their receptors in cancer cells play a role in tumor growth and resistance to treatment. In this review, we summarize evidence indicating that neurotrophin signaling influences medulloblastoma (MB), the most common type of malignant brain cancer afflicting children. We discuss the potential of neurotrophin receptors as new therapeutic targets for the treatment of MB. Overall, activation of TrkA and TrkC types of receptors seem to promote cell death, whereas TrkB might stimulate MB growth, and TrkB inhibition displays antitumor effects. Importantly, we show analyses of the gene expression profile of neurotrophins and their receptors in MB primary tumors, which indicate, among other findings, that higher levels of NTRK1 or NTRK2 are associated with reduced overall survival (OS) of patients with SHH MB tumors

Neurotrophin Signaling in Medulloblastoma

Neurotrophins are a family of secreted proteins that act by binding to tropomyosin receptor kinase (Trk) or p75NTR receptors to regulate nervous system development and plasticity. Increasing evidence indicates that neurotrophins and their receptors in cancer cells play a role in tumor growth and resistance to treatment. In this review, we summarize evidence indicating that neurotrophin signaling influences medulloblastoma (MB), the most common type of malignant brain cancer afflicting children. We discuss the potential of neurotrophin receptors as new therapeutic targets for the treatment of MB. Overall, activation of TrkA and TrkC types of receptors seem to promote cell death, whereas TrkB might stimulate MB growth, and TrkB inhibition displays antitumor effects. Importantly, we show analyses of the gene expression profile of neurotrophins and their receptors in MB primary tumors, which indicate, among other findings, that higher levels of NTRK1 or NTRK2 are associated with reduced overall survival (OS) of patients with SHH MB tumors

Clinical features in osteosarcoma and prognostic implications

Objetivos: Conhecer as características clínicas e determinar os fatores de importância prognóstica de crianças e adolescentes com osteossarcoma. Materiais e métodos: Foram revisados os prontuários de crianças e adolescentes com diagnóstico de osteossarcoma tratados entre janeiro de 1992 e dezembro de 2001 pelo Grupo de Tumores Ósseos do Rio Grande do Sul. Resultados: Foram incluídos no estudo 50 pacientes com idade mediana de 13 anos (3 a 22), sendo 68% pacientes do sexo masculino. Os locais primários foram: 50% fêmur, 30% tíbia, 4% ilíaco, 10% úmero, 2% fíbula e 4% outros. Dezenove pacientes (38%) apresentavam metástases ao diagnóstico. Todos os pacientes foram submetidos a quimioterapia. Quanto ao tratamento cirúrgico, 26 pacientes (52%) foram submetidos a amputação, e 17 a cirurgia conservadora (34%). A desidrogenase láctica maior do que 1.000 UI/ml ao diagnóstico, o índice de necrose inferior a 90% e a presença de metástases influíram negativamente no prognóstico. A probabilidade de sobrevida global em 5 anos foi de 33,2±7,2%, com média de follow-up de 36 meses (6-126); a probabilidade de sobrevida livre de eventos em 5 anos foi de 29,7±7%. A probabilidade de sobrevida livre de eventos em 5 anos dos pacientes não-metastáticos ao diagnóstico foi de 45±10,7%, e a dos metastáticos foi zero (médias de follow-up de 78,4 e 18,7 meses, respectivamente); apenas dois dos 19 pacientes com doença metastática encontram-se fora de tratamento e livres de doença, com follow-up de 18 e 30 meses, respectivamente. Conclusão: A presença de doença metastática e nível sérico de desidrogenase láctica acima de 1.000 UI/ml ao diagnóstico, assim como índice de necrose < 90%, representam fatores prognósticos desfavor áveis. O percentual excessivamente elevado de pacientes com doença metastática ao diagnóstico sugere que se trata de uma população de pacientes com doença biologicamente agressiva ou diagnosticados tardiamente em nosso meio.Objective: To identify the clinical features in osteosarcoma and to investigate their influence on the prognosis of children and adolescents presenting this disease. Material and methods: The records of children and adolescents with osteosarcoma treated by the Bone Tumors Group of the state of Rio Grande do Sul, Brazil, between January 1992 and December 2001 were reviewed. Results: Fifty consecutive patients were included in this study. Mean age at diagnosis was 13 years (3-22); 68% of the patients were males. The primary site of disease was the femur in 50% of the patients, tibia in 30%, pelvis in 4%, humerus in 10%, fibula in 2% and other sites in 4%. Nineteen patients presented metastases at diagnosis (38%). All patients received chemotherapy and were treated with three different schemes. As for surgical treatment, 26 patients (52%) had an amputation and 17 (34%) received conservative surgery. Serum lactic dehydrogenase > 1,000 UI/ml (p = 0.0159, log rank), tumor necrosis < 90% and presence of metastases had a negative influence on prognosis. The overall 5-year survival was of 33.2±7.2% with mean follow-up of 36 months (6-126). Event-free survival was 29.7±7%. The 5-year event-free survival in nonmetastatic patients was 45±10.7%, and zero in metastatic patients (follow-up of 78.4 and 18.7 months, respectively). Only two out of 19 metastatic patients are alive and free of disease at 18 and 30 months respectively. Conclusion: Metastatic disease at diagnosis, serum levels of serum lactic dehydrogenase > 1,000 UI/ml and tumor necrosis < 90% are predictors of unfavorable prognosis. The excessively high incidence of metastatic patients may suggest the presence of an aggressive pattern of disease in our population, or may indicate late diagnosis