Targeting refractory/recurrent neuroblastoma and osteosarcoma with anti-CD3×anti-GD2 bispecific antibody armed T cells.

BACKGROUND: The survival benefit observed in children with neuroblastoma (NB) and minimal residual disease who received treatment with anti-GD2 monoclonal antibodies prompted our investigation into the safety and potential clinical benefits of anti-CD3×anti-GD2 bispecific antibody (GD2Bi) armed T cells (GD2BATs). Preclinical studies demonstrated the high cytotoxicity of GD2BATs against GD2+cell lines, leading to the initiation of a phase I/II study in recurrent/refractory patients. METHODS: The 3+3 dose escalation phase I study (NCT02173093) encompassed nine evaluable patients with NB (n=5), osteosarcoma (n=3), and desmoplastic small round cell tumors (n=1). Patients received twice-weekly infusions of GD2BATs at 40, 80, or 160×106 GD2BATs/kg/infusion complemented by daily interleukin-2 (300,000 IU/m2) and twice-weekly granulocyte macrophage colony-stimulating factor (250 µg/m2). The phase II segment focused on patients with NB at the dose 3 level of 160×106 GD2BATs/kg/infusion. RESULTS: Of the 12 patients enrolled, 9 completed therapy in phase I with no dose-limiting toxicities. Mild and manageable cytokine release syndrome occurred in all patients, presenting as grade 2-3 fevers/chills, headaches, and occasional hypotension up to 72 hours after GD2BAT infusions. GD2-antibody-associated pain was minimal. Median overall survival (OS) for phase I and the limited phase II was 18.0 and 31.2 months, respectively, with a combined OS of 21.1 months. A phase I NB patient had a complete bone marrow response with overall stable disease. In phase II, 10 of 12 patients were evaluable: 1 achieved partial response, and 3 showed clinical benefit with prolonged stable disease. Over 50% of evaluable patients exhibited augmented immune responses to GD2+targets post-GD2BATs, as indicated by interferon-gamma (IFN-γ) EliSpots, Th1 cytokines, and/or chemokines. CONCLUSIONS: This study demonstrated the safety of GD2BATs up to 160×106 cells/kg/infusion. Coupled with evidence of post-treatment endogenous immune responses, our findings support further investigation of GD2BATs in larger phase II clinical trials.

Targeting GD2-positive Refractory/Resistant Neuroblastoma and Osteosarcoma with Anti- CD3 x Anti-GD2 Bispecific Antibody Armed T cells.

Background: Since treatment of neuroblastoma (NB) with anti-GD2 monoclonal antibodies provides a survival benefit in children with minimal residual disease and our preclinical study shows that anti-CD3 x anti-GD2 bispecific antibody (GD2Bi) armed T cells (GD2BATs) were highly cytotoxic to GD2+ cell lines, we conducted a phase I/II study in recurrent/refractory patients to establish safety and explore the clinical benefit of GD2BATs. Methods: The 3+3 dose escalation study (NCT02173093) phase I involved 9 evaluable patients with NB (n=5), osteosarcoma (OST) (n=3), and desmoplastic small round cell tumors (DSRCT) (n=1) with twice weekly infusions of GD2BATs at 40, 80, or 160 x 106 GD2BATs/kg/infusion with daily interleukin 2 (300,000 IU/m2) and twice weekly granulocyte-macrophage colony stimulating factor (250 µg/m2). Phase II portion of the trial was conducted in patients with NB at the dose 3 level of 160 x 106 GD2BATs/kg/infusion but failed to enroll the planned number of patients. Results: Nine of 12 patients in the phase I completed therapy. There were no dose limiting toxicities (DLTs). All patients developed mild and manageable cytokine release syndrome (CRS) with grade 2-3 fevers/chills, headaches, and occasional hypotension up to 72 hours after GD2BAT infusions. GD2-antibody associated pain was not significant in this study. The median OS for patients in the Phase I and limited Phase II was 18.0 and 31.2 months, respectively, whereas the combined OS was 21.1 months. There was a complete bone marrow response with overall stable disease in one of the phase I patients with NB. Ten of 12 phase II patients were evaluable for response: 1 had partial response. Three additional patients were deemed to have clinical benefit with prolonged stable disease. More than 50% of evaluable patients showed augmented immune responses to GD2+ targets after GD2BATs as measured by interferon-gamma (IFN-γ) EliSpots, Th1 cytokines, and/or chemokines. Conclusions: Our study demonstrated safety of up to 160 x 106 cells/kg/infusion of GD2BATs. Combined with evidence for the development of post treatment endogenous immune responses, this data supports further investigation of GD2 BATs in larger Phase II clinical trials.

Reversible Cerebral Vasoconstriction Syndrome and Sickle Cell Disease: A Case Report.

Reversible cerebral vasoconstriction syndrome (RCVS), is rare in the pediatric population and is characterized by severe headaches and other neurologic symptoms. We present a case of RCVS occurring concomitantly with posterior reversible encephalopathy syndrome in an 8-year-old African American child with sickle cell disease (HbSS). Imaging studies including computed tomography, magnetic resonance imaging and cerebral angiography of the brain showed acute hemorrhagic stroke and a beaded appearance of peripheral cerebral vessels. In this report, we focus on the typical features of RCVS and discuss the underlying risk factors that may increase the risk in patients with HbSS disease.

Estudo de 19 anos dos procedimentos odontológicos realizados no Sistema Único de Saúde brasileiro / A 19-years study of the dental procedures performed in the Brazilian Unified Health System

Resumo Introdução A saúde pública no Brasil sofreu grandes mudanças nas últimas décadas. Objetivo Descrever o panorama da produção odontológica realizada pelo SUS de 1999 a 2017 no Brasil e suas macrorregiões. Método Os dados foram obtidos no Sistema de Informação Ambulatorial (SIA-SUS) e do Instituto Brasileiro de Geografia e Estatística (IBGE). Foram criadas taxas de procedimentos (por 100 mil habitantes/ano) realizados em cada macrorregião: procedimentos restauradores, protéticos, coletivos, endodontia, exodontia, periodontia e preventivos de 1999 a 2017. A análise estatística das séries temporais foi realizada utilizando um modelo de regressão linear. Resultados Procedimentos protéticos e de periodontia foram os únicos que apresentaram uma tendência linear positiva em todas as macrorregiões brasileiras (p<0,001). A Endodontia não apresentou tendência positiva no Brasil (p=0,173). Restaurações apresentaram um crescimento na macrorregião Norte (p=0,003) e Centro-Oeste (p<0,001). Exodontias apresentaram na macrorregião Norte uma tendência de aumento (p=0,046) enquanto que, no Centro-Oeste, apresentaram uma diminuição (p=0,049). Procedimentos preventivos (p=0,042) e coletivos (p=0,017) apresentaram uma diminuição da sua produção durante o período. Conclusão A saúde bucal apresentou um grande crescimento dentro do Sistema Único de Saúde nos 19 anos avaliados. Procedimentos de periodontia e de prótese dentária foram aqueles com as maiores tendências de crescimento.

Abstract Background Public health in Brazil has undergone major changes in recent decades. Objective To describe the overview of dental production performed by the Brazilian Unified Health System from 1999 to 2017 in Brazil and its macroregions. Method Data were obtained from the Outpatient Information System (SIA/SUS) and from the Brazilian Institute of Geography and Statistics (IBGE). Procedures rates (per 100,000 inhabitants per year) were established in each macroregion: restorative, prosthetic, collective, endodontic, exodontia, periodontic and preventive procedures. Statistical analysis of the time series was performed using a regression linear model. Results Prosthetic and periodontal procedures were the only ones with a positive linear trend in all Brazilian macroregions (p<0.001). Endodontics did not show a positive trend in Brazil (p=0.173). Restorations showed a growth in the North (p=0.003) and Center-west (p<0.001) macroregions. Exodontia presented a tendency to increase in the North macroregion (p=0.046), while the Midwest presented a decrease of it (p=0.049). Preventive (p=0.042) and collective (p=0.017) procedures showed a decrease in their production during the period. Conclusion Oral health showed great growth within the single health system in the 19 years evaluated. Periodontal procedures and dental prostheses were those with the highest growth trends.

Bone, periodontal and dental pulp regeneration in dentistry: a systematic scoping review

Abstract The aim of presented systematic scoping review was to investigate the actual and future clinical possibilities of regenerative therapies and their ability to regenerate bone, periodontal and pulp with histological confirmation of the nature of formed tissue. Electronic search was conducted using a combination between Keywords and MeSH terms in PubMed, Scopus, ISI-Web of Science and Cochrane library databases up to January 2016. Two reviewers conducted independently the papers judgment. Screened studies were read following the predetermined inclusion criteria. The included studies were evaluated in accordance with Arksey and O'Malley's modified framework. From 1349 papers, 168 completed inclusion criteria. Several characterized and uncharacterized cells used in Cell Therapy have provided bone regeneration, demonstrating bone gain in quantity and quality, even as accelerators for bone and periodontal regeneration. Synthetic and natural scaffolds presented good cell maintenance, however polyglycolid-polylactid presented faster resorption and consequently poor bone gain. The Growth Factor-Mediated Therapy was able to regenerate bone and all features of a periodontal tissue in bone defects. Teeth submitted to Revascularization presented an increase of length and width of root canal. However, formed tissues not seem able to deposit dentin, characterizing a repaired tissue. Both PRP and PRF presented benefits when applied in regenerative therapies as natural scaffolds. Therefore, most studies that applied regenerative therapies have provided promising results being possible to regenerate bone and periodontal tissue with histological confirmation. However, pulp regeneration was not reported. These results should be interpreted with caution due to the short follow-up periods.

Resumo O objetivo da presente Scoping review foi investigar as possibilidades clínicas atuais e futuras das terapias regenerativas e sua capacidade de regenerar tecido ósseo, periodontal e polpar em humanos com confirmação histológica da natureza do tecido formado. Uma busca eletrônica foi realizada utilizando uma combinação entre as palavras-chave e termos MeSH nos bancos de dados PubMed, Scopus, ISI-web of Science e Cochrane library até janeiro de 2016. Dois revisores realizaram de forma independente o julgamento dos documentos. Os estudos selecionados foram lidos seguindo os critérios de inclusão predeterminados. Os estudos incluídos foram avaliados de acordo com a estrutura modificada de Arksey e O'Malley. Dos 1349 artigos, 168 preencheram os critérios de inclusão. Várias células caracterizadas e não caracterizadas promoveram regeneração óssea utilizada em terapias celulares, demonstrando ganho ósseo em quantidade e qualidade, de forma rápida para regeneração óssea e periodontal. Os scaffolds sintéticos e naturais apresentaram boa manutenção celular, no entanto o poliglicol-polilácido apresentou uma reabsorção rápida e, consequentemente, pequeno ganho ósseo. A terapia mediada por fatores de crescimento foi capaz de regenerar tecido ósseo e todas as características de um tecido periodontal. Dentes submetidos à revascularização apresentaram aumento do comprimento e largura do canal radicular. No entanto, os tecidos formados não foram capazes de depositar dentina, caracterizando um tecido reparado. Tanto o PRP quanto o PRF parecem apresentar benefícios quando aplicados em terapias regenerativas sendo um bom scaffold natural. Portanto, a maioria dos estudos que aplicaram terapias regenerativas forneceram resultados promissores sendo possível regenerar tecido ósseo e periodontal com confirmação histológica. No entanto, não foi observada regeneração de polpa dental. Estes resultados devem ser interpretados com cautela.

Produção especializada no SUS em capitais brasileiras com centros de especialidades odontológicas: uma análise descritiva / Specialized production in the unified health system in Brazilian capitals with dental specialty centers: a descriptive analysis

Centros de especialidades odontológicos (CEOs) são estabelecimentos de saúde de âmbito especializado que devem realizar uma quantidade mínima de procedimentos. Objetivos: descrever a produção odontológica especializada e reportar o cumprimento das metas nas capitais brasileiras com CEOs. Materiais e método: foi conduzido um estudo do tipo longitudinal retrospectivo, sendo realizada uma busca por CEOs cadastrados no Cadastro Nacional de Estabelecimentos de Saúde (CNES). A produção odontológica foi pesquisada no Sistema de Informações Ambulatoriais do Sistema Único de Saúde (SIASUS), de maio de 2015 a abril de 2016. Resultados: foram encontrados e considerados elegíveis para o presente estudo 59 CEOs, localizados em 19 capitais brasileiras e no Distrito Federal, sendo 48% CEOs tipo II. Cerca de 730 mil procedimentos especializados foram realizados durante os 12 meses avaliados. Uma taxa de 86% das metas foi cumprida, sendo que cirurgia foi à área com maior cumprimento (92%), seguida de periodontia (89%) e endodontia (76%). Uma das capitais apresentou apenas 33% das metas cumpridas. Três capitais não atingiram nenhuma das metas estabelecidas em procedimentos de endodontia. Conclusão: foi observada uma grande variação no cumprimento das metas entre as capitais com CEOs. Enquanto algumas capitais apresentaram elevado cumprimento das metas, outras exibiram dados preocupantes, principalmente nos procedimentos de endodontia. (AU)

Dental Specialty Centers (Centros de Especialidades Odontológicas ­ CEOs) are specialized health facilities that should perform a minimum number of procedures. Objectives: this study aimed to describe the specialized dental production and report the achievement of goals in Brazilian capitals with CEOs. Materials and method: a retrospective longitudinal study was performed with a search for the CEOs listed in the National Registry of Health Establishments. The dental production was searched in the Outpatient Information System of the Brazilian Unified Health System for the period from May 2015 to April 2016. Results: fifty-nine CEOs were found and considered eligible for the present study. They were located in 19 Brazilian capitals and in the Federal District, whereas 48% were CEOs Type II. Approximately 730 thousand specialized procedures were performed during the 12 months evaluated. A rate of 86% of goals was met and surgery presented the highest achievement (92%), followed by periodontics (89%) and endodontics (76%). One of the capitals achieved only 33% of the goals. Three capitals did not achieve any of the goals set for endodontic procedures. Conclusion: there was a great variation in the achievement of goals among capitals with CEOs. While some capitals showed high achievement of goals, others presented concerning data, especially for endodontic procedures. (AU)

Venous Blood Derivatives as FBS-Substitutes for Mesenchymal Stem Cells: A Systematic Scoping Review.

Although the biological properties of mesenchymal stem cells (MSC) are well-characterized in vitro, MSC clinical application is still far away to be achieved, mainly due to the need of xenogeneic substances for cell expansion, such as fetal bovine serum (FBS). FBS presents risks regarding pathogens transmissions and internalization of animal's proteins, which can unleash antigenic responses in patients after MSC implantation. A wide range of venous blood derivatives (VBD) has been reported as FBS substitutes showing promising results. Thus, the aim of this study was to conduct a systematic scoping review to analyze whether VBD are effective FBS substitutes for MSC ex vivo expansion. The search was performed in SciVerse ScopusTM, PubMed, Web of ScienceTM, BIREME, Cochrane library up to January 2016. The keywords were selected using MeSH and entry terms. Two independent reviewers scrutinized the records obtained considering specific inclusion criteria. The included studies were evaluated in accordance with a modified Arksey and O' Malley's framework. From 184 found studies, 90 were included. Bone marrow mesenchymal stem cells (BMMSC) were presented in most of these studies. Overall, VBD allowed for either, maintenance of MCS's fibroblast-like morphology, high proliferation, high colony-formation ability and maintenance of multipotency. Besides. MSC expanded in VBD supplements presented higher mitogen activity than FBS. VBD seems to be excellent xeno-free serum for ex vivo expansion of mesenchymal stem cells. However, an accentuated heterogeneity was observed between the carried out protocols for VBD isolation did not allowing for direct comparisons between the included studies.

Venous Blood Derivatives as FBS-Substitutes for Mesenchymal Stem Cells: A Systematic Scoping Review

Abstract Although the biological properties of mesenchymal stem cells (MSC) are well-characterized in vitro, MSC clinical application is still far away to be achieved, mainly due to the need of xenogeneic substances for cell expansion, such as fetal bovine serum (FBS). FBS presents risks regarding pathogens transmissions and internalization of animal's proteins, which can unleash antigenic responses in patients after MSC implantation. A wide range of venous blood derivatives (VBD) has been reported as FBS substitutes showing promising results. Thus, the aim of this study was to conduct a systematic scoping review to analyze whether VBD are effective FBS substitutes for MSC ex vivo expansion. The search was performed in SciVerse ScopusTM, PubMed, Web of ScienceTM, BIREME, Cochrane library up to January 2016. The keywords were selected using MeSH and entry terms. Two independent reviewers scrutinized the records obtained considering specific inclusion criteria. The included studies were evaluated in accordance with a modified Arksey and O' Malley's framework. From 184 found studies, 90 were included. Bone marrow mesenchymal stem cells (BMMSC) were presented in most of these studies. Overall, VBD allowed for either, maintenance of MCS's fibroblast-like morphology, high proliferation, high colony-formation ability and maintenance of multipotency. Besides. MSC expanded in VBD supplements presented higher mitogen activity than FBS. VBD seems to be excellent xeno-free serum for ex vivo expansion of mesenchymal stem cells. However, an accentuated heterogeneity was observed between the carried out protocols for VBD isolation did not allowing for direct comparisons between the included studies.

Resumo Embora as propriedades biológicas das células-tronco mesenquimais (MSC) sejam bem caracterizadas in vitro, a aplicação clínica das MSC ainda está longe de ser alcançada, principalmente devido à necessidade de substâncias xenogênicas para expansão celular, como o soro fetal bovino (FBS). O FBS apresenta riscos quanto às transmissões de patógenos e à internalização de proteínas animais, o que pode desencadear respostas antigênicas em pacientes após a implantação das MSC. Uma vasta gama de derivados do sangue venoso (VBD) têm sido relatada como substitutos do FBS mostrando resultados promissores. Assim, o objetivo deste estudo foi conduzir uma revisão de escopo sistemática para analisar se VBD poderiam ser substitutos do FBS eficazes para expansão das MSC em condições ex vivo. A pesquisa foi realizada no SciVerse Scopus, PubMed, Web of Science, BIREME e biblioteca Cochrane até janeiro de 2016. As palavras-chave foram selecionadas usando MeSH e entre termos. Dois revisores independentes examinaram os registros obtidos considerando critérios de inclusão específicos. Os estudos incluídos foram avaliados de acordo com uma estrutura modificada de Arksey e O 'Malley. Dos 184 estudos encontrados, 90 foram incluídos. As células-tronco da medula óssea (BMMSC) foram utilizadas na maior parte destes estudos. Em geral, o VBD permitiu tanto a manutenção da morfologia semelhante a fibroblastos das MCS, alta proliferação, alta capacidade de formação de colônias e manutenção de multipotêncialidade. Além disso, as MSC expandidas em suplementos derivados do sangue venoso apresentaram uma maior atividade mitogênica do que as expandidas em FBS. Os VBD parecem ser excelentes soro livres de agentes xenogênicos para expansão ex vivo de MSC. Entretanto, observou-se uma heterogeneidade acentuada entre os protocolos realizados para o isolamento VBD, não permitindo assim comparações diretas entre os estudos incluídos.

Combination of clofarabine, cyclophosphamide, and etoposide for relapsed or refractory childhood and adolescent acute myeloid leukemia.

Relapsed/refractory acute myeloid leukemia (AML) has an extremely poor prognosis. We describe 17 children and adolescents with relapsed/refractory AML who received clofarabine, cyclophosphamide, and etoposide. Seven patients (41%) responded: 4 with a complete response (CR); 1 with CR with incomplete platelet recovery; and 2 with a partial response. Additionally, 4 developed hypocellular marrow without evidence of leukemia; 5 patients had resistant disease; and 1 suffered early toxic death. After further therapy including transplantation, 4 patients (24%) are alive without evidence of disease at a median of 60 months. This anthracycline-free regimen may be studied for relapsed or refractory AML, but due to the high risk of marrow aplasia reduced doses of clofarabine and cyclophosphamide should be used.

Treatment of Refractory Infantile Hemangiomas and Pulmonary Hypertension With Sirolimus in a Pediatric Patient.

Infantile hemangioma is a benign vascular neoplasm that spontaneously involutes over time. Management, when needed, consists of medications, laser treatment and surgical excision. We describe a 3-year-old girl who presented shortly after birth with diffuse cutaneous hemangiomas, hepatosplenomegaly with liver lesions, anemia, and acute heart failure. She was diagnosed with hepatic and cutaneous infantile hemangioma based on skin biopsy. She developed progressive pulmonary hypertension with numerous pulmonary nodules suspicious for pulmonary arteriovenous malformations. She was started on sirolimus and had significant improvement in her pulmonary hypertension and liver lesions. This report supports prior studies that sirolimus is effective for vascular anomalies including IH refractory to conventional therapy.

Tratamento criogênico para elevar a quantidade de macroporos no plasma rico em fibrina utilizado como scaffold em engenharia tecidual / Cryogenic treatment to increase the amount of macropores in plasma rich in fibrin used as scaffold in tissue engineering

Objetivos: Investigar se o tratamento criogênico é capaz de elevar a quantidade de macroporos no Plasma Rico em Fibrina (PRF) utilizado como scaffold sem destruir totalmente sua integridade estrutural. Métodos: Três amostras de sangue (10 ml) foram processadas para obtenção do PRF. As amostras foram armazenadas em ultrafreezer (-80°C) e armazenadas por sete dias e um ano. Como controle foi utilizado um PRF imediatamente após sua obtenção. Após os respectivos períodos de armazenamento, cada PRF foi preparado para análises histológicas. Três áreas representativas de cada amostra foram selecionadas e avaliadas no software Image J quanto ao tamanho dos poros: macro ≥ 50 µm e microporos < 50 µm. Resultados: Após sete dias e um ano de criopreservação foi observada uma área total de macroporos compreendendo 76% e 82% do PRF, respectivamente. No PRF processado imediatamente após sua obtenção observamos 64% de macroporos. Além disso, a criopreservação promoveu uma alteração do arranjo estrutural do PRF. Conclusão: O tratamento criogênico do PRF a -80°C (por 7 dias ou um ano) foi capaz de elevar a quantidade de macroporos mantendo uma considerada quantidade de microporos. Com o aumento do tempo de tratamento criogênico um maior número de macroporos foi observado.

Objectives: To investigate whether the cryogenic treatment is able to increase the amount of macropores in the Fibrin Rich Plasma (PRF) used as scaffold, without destroying its structural integrity. Methods: Three blood samples (10 ml) were processed to obtain the PRF. The samples were stored in ultra-freezer (-80° C) and maintained for seven days or one year. As a control, PRF immediately after their acquisition was used. After each storage period, PRF was prepared for histological analysis. Three representative areas of each sample were selected and evaluated in Image J software for pore size: macro ≥ 50 µm and micropores < 50 µm. Results: After seven days and after one year of cryopreservation was observed a total area of macropores comprising 76% and 82% of the PRF, respectively. In PRF processed immediately after collection was observed 64% of macropores. As observed, the cryopreservation changed the structural arrangement of the PRF. Conclusion: The cryogenic treatment of PRF at -80 ° C (for 7 days or one year) increased the amount of macropores maintaining a considerate amount of micropores. A greater number of macropores was observed as the cryogenic treatment time was increased.

Terapias para regeneração do disco articular

O presente estudo revisou a literatura científica em busca das perspectivas e dos principais desafios enfrentados pelas terapias de regeneração do disco articular. Revisão de literatura: a disfunção temporomandibular (DTM) é uma desordem de etiologia multifatorial em que patologias, deformidades e mau posicionamento do disco da articulação temporomandibular (ATM) estão presentes em até 70% dos casos diagnosticados. Dessa forma, o emprego de conhecimentos e princí- pios da engenharia tecidual para o desenvolvimento de terapias que busquem a regeneração do disco articular pode ser uma opção de tratamento futuro. Células- -tronco mesenquimais (MSC) são frequentemente empregadas, apresentando a capacidade de se diferenciar em condrócitos e depositar tecido semelhante ao da ATM. Estudos têm apontado que essas células podem apresentar melhor regeneração que células removidas da própria ATM lesionada, que apresentam uma menor deposição de matriz extracelular. Abordagens para reconstrução têm empregado, principalmente, scaffolds sintéticos, como polímeros e hidrogéis, assim como scaffolds naturais de origem colágena. Esses materiais têm possibilitado a proliferação celular e a deposição de matriz extracelular. Técnicas de descelularização com diversos solventes orgânicos têm apresentado a capacidade de não desenvolver resposta imune, sendo possível sua utilização. A utilização de fatores de crescimento parece contribuir significativamente na sinalização e diferenciação celular, incrementando a deposição de tecido cartilaginoso. Considerações finais: apesar de a regeneração tecidual do disco articular se apresentar como uma provável opção de tratamento para os diversos tipos de DTM, a literatura ainda se encontra em fase inicial de investigação, com estudos predominantemente in vitro e in vivo.

Novel miRNA-31 and miRNA-200a-Mediated Regulation of Retinoblastoma Proliferation.

Retinoblastoma is the most common intraocular tumor in children. Current management includes broad-based treatments such as chemotherapy, enucleation, laser therapy, or cryotherapy. However, therapies that target specific pathways important for retinoblastoma progression could provide valuable alternatives for treatment. MicroRNAs are short, noncoding RNA transcripts that can regulate the expression of target genes, and their aberrant expression often facilitates disease. The identification of post-transcriptional events that occur after the initiating genetic lesions could further define the rapidly aggressive growth displayed by retinoblastoma tumors. In this study, we used two phenotypically different retinoblastoma cell lines to elucidate the roles of miRNA-31 and miRNA-200a in tumor proliferation. Our approach confirmed that miRNAs-31 and -200a expression is significantly reduced in human retinoblastomas. Moreover, overexpression of these two miRNAs restricts the expansion of a highly proliferative cell line (Y79), but does not restrict the growth rate of a less aggressive cell line (Weri1). Gene expression profiling of miRNA-31 and/or miRNA-200a-overexpressing cells identified differentially expressed mRNAs associated with the divergent response of the two cell lines. This work has the potential to enhance the development of targeted therapeutic approaches for retinoblastoma and improve the efficacy of treatment.

Secondary malignant neoplasms after high-dose chemotherapy and autologous stem cell rescue for high-risk neuroblastoma.

BACKGROUND: Outcomes for high-risk neuroblastoma remain poor. Modern treatment protocols utilizing intense induction followed by myeloablative consolidation chemotherapy with autologous stem cell rescue (ASCR) have improved survival rates, but the long-term sequelae, including development of secondary malignant neoplasms (SMN), are just now surfacing. METHODS: We retrospectively reviewed data from 87 patients with high-risk neuroblastoma who were treated with intensive induction chemotherapy followed by ASCR between January 1991 and July 2011 following one of two institutional protocols: Chicago Pilot 1 (CP1; n = 12) and Chicago Pilot 2 (CP2; n = 75). RESULTS: The 15-year overall survival rate for all 87 patients was 33.9% (95% confidence interval [CI], 23.1-45.0%). The 10- and 15-year cumulative incidence of SMN was 16.5% (95%CI, 7.2-38.0%) and 34.2% (95%CI, 18.6-63.1%), respectively, without evidence of a plateau at 15 years. Six of the 10 patients (n = 2 in CP1 and n = 8 in CP2) who developed SMN had hematologic malignancies including acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS). Solid tumors included thyroid papillary carcinoma, chondrosarcoma, hepatocellular carcinoma, and biliary adenocarcinoma. CONCLUSION: A significantly higher incidence of SMN, especially hematological malignancies, was observed in this cohort compared to older neuroblastoma studies, potentially due to exposure to epipodophyllotoxins and a high cumulative dose of alkylating agents these patients received. The risk of developing an SMN continued to increase with survival time and did not reach the plateau at 15 years. Although the number of the patients is relatively small, our study emphasizes the need for life-long follow-up of survivors who were treated using modern therapy.

MicroRNAs-449a and -449b exhibit tumor suppressive effects in retinoblastoma.

Retinoblastoma is the most common pediatric cancer of the eye. Currently, the chemotherapeutic treatments for retinoblastoma are broad-based drugs such as vincristine, carboplatin, or etoposide. However, therapies targeted directly to aberrant signaling pathways may provide more effective therapy for this disease. The purpose of our study is to illustrate the relationship between the expressions of miRs-449a and -449b to retinoblastoma proliferation and apoptosis. We are the first to confirm an inhibitory effect of miR-449a and -449b in retinoblastoma by demonstrating significantly impaired proliferation and increased apoptosis of tumor cells when these miRNAs are overexpressed. This study suggests that these miRNAs could serve as viable therapeutic targets for retinoblastoma treatment.

Differentially expressed miRNAs in retinoblastoma.

MicroRNAs (miRNAs) are short non-coding RNA transcripts that have the ability to regulate the expression of target genes, and have been shown to influence the development of various tumors. The purpose of our study is to identify aberrantly expressed miRNAs in retinoblastoma for the discovery of potential therapeutic targets for this disease, and to gain a greater understanding of the mechanisms driving retinoblastoma progression. We report 41 differentially expressed miRNAs (p<0.05) in 12 retinoblastomas as compared to three normal human retinae. Of these miRNAs, many are newly identified as being differentially expressed in retinoblastoma. Further, we report the validations of five of the most downregulated miRNAs in primary human retinoblastomas (p<0.05), human retinoblastoma cell lines, and mouse retinoblastoma cell lines. This serves as the largest and most comprehensive retinoblastoma miRNA analysis to date with corresponding clinical and pathological characteristics. This is an essential step in the discovery of miRNAs associated with retinoblastoma progression, and in the identification of potential therapeutic targets for this disease.

Relapsed or refractory pediatric acute lymphoblastic leukemia: current and emerging treatments.

Relapsed acute lymphoblastic leukemia (ALL) represents a major cause of morbidity and mortality in pediatrics. With contemporary chemotherapy, >85% of patients with newly diagnosed ALL survive. Unfortunately, 20% of these patients will relapse and for these children, outcomes remain poor despite our best known chemotherapy protocols. Most of these children will achieve a second complete remission, but maintaining this remission remains difficult. Because relapsed ALL is such a significant cause of morbidity and mortality, it is the focus of much research interest. Efforts have been made and continue to focus on understanding the underlying biology that drives relapse. The role of hematopoietic stem cell transplantation in relapsed ALL remains unclear, but many clinicians still favor this for high-risk patients given the poor prognosis with current chemotherapy alone. It is important to use new drugs with little cross-resistance in the treatment of relapsed ALL. New classes of agents are currently being studied. We also discuss prognostic factors and the biology of relapsed ALL.

Evidence of transmission of Burkholderia cepacia, Burkholderia multivorans and Burkholderia dolosa among persons with cystic fibrosis.

Previous studies have identified specific Burkholderia cepacia complex strains that are common to multiple persons with cystic fibrosis (CF). Such so-called epidemic strains have an apparent enhanced capacity for inter-patient spread and reside primarily in Burkholderia cenocepacia (formerly B. cepacia complex genomovar III). We sought to identify strains from B. cepacia complex species other than B. cenocepacia that are similarly shared by multiple CF patients. We performed genotype analysis of 360 recent sputum culture isolates from 360 persons residing in 29 cities by using repetitive extragenic palendromic polymerase chain reaction (rep-PCR) and pulsed field gel electrophoresis. The results indicate that sharing of a common Burkholderia multivorans strain occurs relatively infrequently; however, several small clusters of patients infected with the same strain were identified. A cluster of seven patients infected with the same B. cepacia (genomovar I) strain was found. We also identified a large group of 28 patients receiving care in the same treatment center and infected with the same Burkholderia dolosa strain. These observations suggest that B. cepacia complex strains in species other than B. cenocepacia may be spread among CF patients.

Comparative assessment of genotyping methods for epidemiologic study of Burkholderia cepacia genomovar III.

We analyzed a collection of 97 well-characterized Burkholderia cepacia genomovar III isolates to evaluate multiple genomic typing systems, including pulsed-field gel electrophoresis (PFGE), BOX-PCR fingerprinting and random amplified polymorphic DNA (RAPD) typing. The typeability, reproducibility, and discriminatory power of these techniques were evaluated, and the results were compared to each other and to data obtained in previous studies by using multilocus restriction typing (MLRT). All methods showed excellent typeability. PFGE with SpeI was more reproducible than RAPD and BOX-PCR fingerprinting. The discriminatory power of the methods was variable, with PFGE and RAPD typing having a higher index of discrimination than BOX-PCR fingerprinting. In general, the results obtained by PFGE, BOX-PCR fingerprinting, and MLRT were in good agreement. Our data indicate that different genomic-based methods can be used to type B. cepacia genomovar III isolates depending on the situation and the epidemiologic question being addressed. PFGE and RAPD fingerprinting are best suited to addressing small-scale studies (i.e., local epidemiology), whereas BOX-PCR fingerprinting is more appropriate for large-scale studies (i.e., global epidemiology). In this regard, BOX-PCR fingerprinting can be considered a rapid and easy alternative to MLRT.