Neurotoxidad inducida por ifosfamida / Ifosfamide-induced neurotoxicity

Introducción: La ifosfamida es un agente alquilante utilizado para el tratamiento de enfermedades oncohematológicas. Entre sus eventos adversos agudos se encuentra la neurotoxicidad. Esta puede presentarse desde el inicio de la infusión hasta tres días después. El tratamiento consiste en suspender la administración y asegurar una adecuada hidratación. Objetivo: Describir eventos neurológicos asociados al uso de ifosfamida en pacientes pediátricos con enfermedades oncohematológicas. Materiales y métodos: Estudio observacional, descriptivo, retrospectivo y transversal. Los datos se obtuvieron de historias clínicas de pacientes internados en el Hospital Garrahan que infundieron ifosfamida y desarrollaron síntomas neurológicos. Se analizaron edad, diagnóstico de base, dosis de ifosfamida, síntomas neurológicos y su relación con la infusión, tratamiento instaurado, exámenes complementarios y posibles factores de riesgo asociados. Resultados: Se registraron un total de catorce eventos neurológicos en doce pacientes, sin diferencia de sexo, con una mediana de edad de 9,5 años. La enfermedad de base más prevalente fue osteosarcoma. Las convulsiones fueron el síntoma más frecuente (50%), seguido de somnolencia y paresias. La combinación de ifosfamida y etopósido con/sin carboplatino se asoció en un 36% cada uno. El 64% desarrolló neurotoxicidad dentro de las primeras cuatro horas. Ningún paciente presentó alteraciones en los exámenes complementarios. Todos presentaron recuperación ad integrum. Conclusión: Este estudio brinda información acerca del tiempo de aparición de esta complicación, lo cual facilitará su detección precoz y tratamiento oportuno (AU)

Introduction: Ifosfamide is an alkylating agent used for the treatment of cancer. Among its acute adverse events is neurotoxicity. This can occur from the beginning of the infusion up to three days afterwards. Treatment consists of discontinuing administration and ensuring adequate hydration. Objective: To describe neurological events associated with the use of ifosfamide in children with cancer. Materials and methods: Observational, descriptive, retrospective, and cross-sectional study. Data were obtained from clinical records of patients admitted to the Garrahan Hospital who received ifosfamide infusion and developed neurological symptoms. Age, baseline diagnosis, ifosfamide dose, neurological symptoms and their relationship with the infusion, treatment, complementary tests, and possible associated risk factors were analyzed. Results: A total of fourteen neurological events were recorded in twelve patients, without difference in sex and with a median age of 9.5 years. The most prevalent underlying disease was osteosarcoma. Seizures were the most frequent symptom (50%), followed by drowsiness and paresis. The combination of ifosfamide and etoposide with/without carboplatin was associated in 36% each. Sixty-four percent developed neurotoxicity within the first four hours. None of the patients presented with abnormalities in the complementary examinations. All recovered ad integrum. Conclusion: This study provides information about the time of onset of this complication, which will facilitate its early detection and timely treatment (AU)

Inhibition of Ciliogenesis Enhances the Cellular Sensitivity to Temozolomide and Ionizing Radiation in Human Glioblastoma Cells / 生物医学与环境科学（英文）

Objective@#To investigate the function of primary cilia in regulating the cellular response to temozolomide (TMZ) and ionizing radiation (IR) in glioblastoma (GBM).@*Methods@#GBM cells were treated with TMZ or X-ray/carbon ion. The primary cilia were examined by immunostaining with Arl13b and γ-tubulin, and the cellular resistance ability was measured by cell viability assay or survival fraction assay. Combining with cilia ablation by IFT88 depletion or chloral hydrate and induction by lithium chloride, the autophagy was measured by acridine orange staining assay. The DNA damage repair ability was estimated by the kinetic curve of γH2AX foci, and the DNA-dependent protein kinase (DNA-PK) activation was detected by immunostaining assay.@*Results@#Primary cilia were frequently preserved in GBM, and the induction of ciliogenesis decreased cell proliferation. TMZ and IR promoted ciliogenesis in dose- and time-dependent manners, and the suppression of ciliogenesis significantly enhanced the cellular sensitivity to TMZ and IR. The inhibition of ciliogenesis elevated the lethal effects of TMZ and IR via the impairment of autophagy and DNA damage repair. The interference of ciliogenesis reduced DNA-PK activation, and the knockdown of DNA-PK led to cilium formation and elongation.@*Conclusion@#Primary cilia play a vital role in regulating the cellular sensitivity to TMZ and IR in GBM cells through mediating autophagy and DNA damage repair.

Encefalite herpética associada a mieloma múltiplo: desafio diagnóstico / Herpetic encephalitis associated with multiple myeloma: a diagnostic challenge

O mieloma múltiplo é a segunda neoplasia onco-hematológica mais comum, correspondendo a 1% das neoplasias malignas. Trata-se de uma condição subdiagnosticada, assim como a encefalite herpética. Entretanto, é comum a relação do mieloma com infecções, em decorrência do acometimento da imunidade humoral. A encefalite viral herpética tem como principal agente o vírus do herpes simples 1. O caso foi descrito baseado em um raciocínio clínico, visando contribuir para uma melhor caracterização do quadro clínico e do diagnóstico de duas entidades clínicas que possuem baixa suspeição diagnóstica e elevada morbimortalidade. Durante o curso da investigação, foram propostas variadas etiologias como responsáveis pelo rebaixamento do nível de consciência, levando a uma pesquisa de um espectro mais amplo de hipóteses diagnósticas, as quais precederam a confirmação do diagnóstico final. O quadro clínico atípico descrito apresentou obstáculos à suspeição diagnóstica correta, pois a ausência dos sinais e sintomas característicos de ambas as doenças levaram à pesquisa de um arsenal mais amplo de diagnósticos diferenciais. Assim, o atraso no diagnóstico e o início tardio do tratamento foram fatores que contribuíram para o prognóstico reservado do paciente. A associação dessas doenças é pouco descrita na literatura, de modo que mais estudos acerca do assunto se fazem necessários. (AU)

Multiple myeloma is the second most common onco-hematologic neoplasm, accounting for 1% of malignant neoplasms. As herpetic encephalitis, it is an underdiagnosed condition. However, the relation of myeloma with infections is common, due to the involvement of humoral immunity. Herpetic encephalitis has as its main etiological agent the herpes simplex virus 1. The case was described based on a clinical reasoning, aiming to contribute to a better characterization of the clinical picture and diagnosis of two entities that have low rates of diagnostic suspicion and high rates of morbidity and mortality. During the course of investigation, several etiologies were proposed as responsible for the decreased level of consciousness, leading to a search for a broader range of diagnostic hypotheses, which preceded confirmation of the final diagnosis. The atypical clinical picture described presented obstacles to the correct diagnostic suspicion, as the absence of symptoms and signs characteristic of both diseases led to the search for a broader arsenal of differential diagnoses. Thus, delayed diagnosis and late treatment were factors that contributed to the patient's reserved prognosis. The association of these diseases is poorly described in the literature, so further studies on that subject are required. (AU)

Establishment of a mouse model bearing orthotopic temozolomide-resistant glioma / 南方医科大学学报

OBJECTIVE@#To establish a mouse model bearing orthotopic temozolomide (TMZ)-resistant glioma that mimics the development of drug resistance in gliomas @*METHODS@#Seventy-eight adult C57BL/6 mice were randomly divided into 6 groups (@*RESULTS@#The mouse models bearing TMZresistant glioma was successfully established. The cells from the high-dose induced group showed a significantly higher colony-forming rate than those from the high-dose control group (@*CONCLUSIONS@#Progressive increase of TMZ doses in mice bearing orthotopic gliomas can effectively induce TMZ resistance of the gliomas.

Patterns of recurrence and outcomes of glioblastoma multiforme treated with chemoradiation and adjuvant temozolomide

OBJECTIVES: To assess the patterns of failure and prognostic factors in Brazilian patients with glioblastoma multiforme (GBM) treated with radiotherapy (RT) and concurrent and adjuvant temozolomide (TMZ). METHODS: Patients with diagnosed GBM post-resection received postoperative RT. TMZ was administered concurrently at 75 mg/m2/day for 28 consecutive days and adjuvant therapy at 150-200 mg/m2/day for 5 days every 28 days. Radiographic failure was defined as any new T1-enhancing lesion or biopsy-confirmed progressive enhancement inside of the radiation field. When possible, patients with recurrence were salvaged with metronomic TMZ, either in combination with a local treatment or alone (surgery or re-irradiation). Several prognostic factors were evaluated for overall survival (OS). Univariate and multivariate analyses were performed to identify significant factors. A p-value <0.05 was considered significant. RESULTS: This study included 50 patients. The median follow-up time was 21 months. The median RT dose was 60 Gy and all patients received concomitant TMZ. During follow-up, 41 (83.6%) failures were observed, including 34 (83%) in-field, 4 (9.7%) marginal, and 3 (7.3%) distant failures. Metronomic TMZ was used as salvage treatment in 22 (44%) cases and in combination with local treatment in 12 (24%) cases. The median OS and progression-free survival times for the entire cohort were 17 and 9 months, respectively. In univariate analysis, the following factors were significant for better OS: maximal surgical resection (p=0.03), Karnofsky Performance Score (KPS)>70 at diagnosis (p=0.01), metronomic TMZ treatment (p=0.038), recursive partitioning analysis class III (p=0.03), and time to failure >9 months (p=0.0001). In multivariate analysis, the following factors remained significant for better OS: metronomic TMZ (p=0.01) and time to failure >9 months (p=0.0001). CONCLUSION: The median OS of Brazilian patients with GBM treated with RT and TMZ was satisfactory. Although TMZ therapy has become the standard of care for patients with newly diagnosed GBM, the recurrence rate is extremely high. Metronomic TMZ as salvage treatment improved survival in these patients.

Aconselhamento telefônico: identificação de sintomas em pacientes com linfoma em quimioterapia antineoplásica / Consulta telefónica: identificación de síntomas en pacientes con linfoma en quimioterapia antineoplásica / Telephone counseling: identification of symptoms in patients with lymphoma undergoing antineoplastic chemotherapy

Resumo Objetivo Identificar os sinais e sintomas apresentados por pacientes com Linfoma de Hodgkin submetidos ao protocolo quimioterápico composto por Doxorrubicina, Bleomicina, Vimblastina e Dacarbazina (ABVD) por meio de aconselhamento telefônico e comparar os escores de gradação dos sinais e sintomas apresentados nos ciclos do protocolo. Métodos Descritivo, prospectivo, quantitativo. Sete pacientes receberam aconselhamento telefônico, em 24 tempos de chamadas programadas e não programadas, correspondentes a 6 ciclos de quimioterapia com protocolo ABVD. Utilizou-se o Inventário de Sintomas do M.D Anderson e o Critério Comum de Terminologia para Eventos Adversos, para a gradação dos sintomas e um protocolo de condutas. Realizou-se análise descritiva e analítica. Resultados Duzentas e oitenta e seis chamadas telefônicas geraram1.870 queixas sintomáticas. Nas chamadas programadas, as queixas com maior prevalência foram fadiga, preocupações, falta de apetite, vômitos e náuseas. Quanto a interferência nas atividades de vida diária, os itens relacionados a atividades em geral, no trabalho e dificuldade para caminhar, além de alterações no humor foram relatados em maior frequência. Nas chamadas não programadas, a falta de apetite e desregulação menstrual foram as queixas mais recorrentes. Na análise da progressão dos sintomas, observou-se aumento de náuseas e vômitos (p=0,02), diminuição da fadiga e falta de ar (p≤0,03), melhora do sono (p=0,02) e diminuição do estresse (p=0,02). Conclusão A fadiga, náusea, vômito e alteração nas atividades de trabalho foram relatados frequentemente. Houve progressão de náuseas e vômitos, mas regressão da fadiga e do estresse. O aconselhamento telefônico permitiu a comunicação e o manejo rápido de um número expressivo de sintomas.

Resumen Objetivo Identificar los signos y síntomas presentados por pacientes con linfoma de Hodgkin sometidos al protocolo quimioterápico compuesto por doxorrubicina, bleomicina, vinblastina y dacarbazina (ABVD) mediante consulta telefónica, y comparar los puntajes de graduación de los signos y síntomas presentados en los ciclos del protocolo. Métodos Descriptivo, prospectivo, cuantitativo. Siete pacientes recibieron asesoramiento telefónico en 24 momentos de llamadas programadas y no programadas, correspondientes a 6 ciclos de quimioterapia con protocolo ABVD. Se utilizó el Inventario de Síntomas de M. D. Anderson y el Criterio de Terminología Común para Efectos Adversos, para la puntuación de lis síntomas, y un protocolo de conductas. Se realizó análisis descriptivo y analítico. Resultados Doscientas ochenta y seis llamadas telefónicas determinaron 1.870 quejas sintomáticas. En las llamadas programadas, las quejas más prevalentes fueron: fatiga, preocupaciones, falta de apetito, vómitos y náuseas. Respecto a interferencia en actividades cotidianas, los ítems relacionados con actividad en general, laboral y dificultad para caminar, además de cambios del humor, fueron informados con mayor frecuencia. En llamadas no programadas, la falta de apetito y la irregularidad menstrual resultaron las quejas más habituales. En el análisis de progresión de los síntomas se observó aumento de náuseas y vómitos (p=0,02), disminución de fatiga y falta de aire (p≤0,03), mejora del sueño (p=0,02) y disminución del estrés (p=0,02). Conclusión Hubo informe frecuente de fatiga, náuseas, vómitos y cambios en actividades laborales. Existió progresión de náuseas y vómitos, y regresión de fatiga y estrés. La consulta telefónica permitió comunicación y rápido manejo de una expresiva cantidad de síntomas.

Abstract Objective To identify through telephone counselling the signs and symptoms presented by patients with Hodgkin's Lymphoma undergoing chemotherapy with the protocol composed by doxorubicin, bleomycin, vinblastine and dacarbazine and to compare severity scores of the signs and symptoms presented in the cycles of the protocol. Methods Descriptive, prospective, quantitative study. Seven patients received telephone counselling in 24 scheduled and unscheduled calls, corresponding to 6 ABVD chemotherapy cycle. The MD Anderson Symptom Inventory and the Common Terminology Criteria for Adverse Events were used for scoring the symptoms, along with a conduct protocol. A descriptive and analytical analysis was conducted. Results Two hundred and eighty-six telephone calls generated 1,870 symptomatic complaints. In scheduled calls, the most prevalent complaints were fatigue, distress, lack of appetite, vomiting and nausea. As for the interference in daily life activities, the items related to general activities, work, difficulty walking, and mood changes were reported more frequently. In unscheduled calls, lack of appetite and irregular menstruation were the most recurring complaints. The analysis of the progression of symptoms showed an increase in nausea and vomiting (p=0.02), decrease in fatigue and shortness of breath (p≤0.03), improvement in sleep (p=0.02) and decrease of stress (p=0.02). Conclusion Fatigue, nausea, vomiting and alterations in work activities were frequently reported. There was progression of nausea and vomiting but regression of fatigue and stress. Telephone consultation allowed a rapid communication and management of an expressive number of symptoms.

Miocardiopatia não compactada em gestante com linfoma não Hodgkin. Relato de caso / Non-compaction cardiomyopathy in pregnant women with non-Hodgkin lymphoma: a case report

A miocardiopatia não compactada é uma doença congênita rara, que pode ocorrer isoladamente ou associada a outros defeitos, por falha no processo de compactação das fibras miocárdicas, resultando na persistência de trabeculações e recessos profundos. A associação entre a miocardiopatia não compactada e gestação é incomum na literatura, assim como a relação com macroglobulinemia de Waldenstrom, um tipo de linfoma não Hodgkin. Descrevemos aqui a rara associação destas três patologias. Trata-se de paciente do sexo feminino, sem antecedentes hematológicos, neoplasias ou cardiopatias, que procurou o serviço com queixa de astenia progressiva, dores no corpo, perda ponderal importante e anemia. Na investigação diagnóstica, a imunoeletroforese de proteína constatou pico monoclonal em IgM Kappa, com inventário medular por imunofenotipagem e biópsia de medula óssea com Kappa+, CD19+, CD20+, CD38 e CD79b, confirmando diagnóstico de neoplasia de linfócitos B maduros. Na terapêutica, optou-se pelo esquema de primeira linha com dexametasona, rituximabe e ciclofosfamida (DRC) − este último considerado agente alquilante cardiotóxico. Em triagem pré-quimioterápica, o eletrocardiograma mostrou alteração da repolarização ventricular anterosseptal. O ecocardiograma transtorácico evidenciou trabeculações excessivas no ápice do ventrículo esquerdo, sugerindo não compactação do miocárdio. A ressonância magnética confirmou o diagnóstico. Foi iniciada terapia com metoprolol e ácido acetilsalisílico. Todavia, após o último ciclo de terapia quimioterápica, paciente descobriu gravidez (G1P1A0). O período gestacional e o puerpério evoluíram sem manifestações clínicas de insuficiência cardíaca, em classe funcional I (New York Heart Association), mesmo com redução da fração de ejeção do ventrículo esquerdo ao ecocardiograma transtorácico. (AU)

Non-compaction cardiomyopathy is a rare congenital disease that can occur in isolation or associated with other defects, due to failure in compaction of myocardial fiber, resulting in persistence of myocardial trabeculations and deep recesses. The association between non-compaction cardiomyopathy and gestation, as well as the relationship with Waldenstrom's macrobulinemia, a type of Non-Hodgkin's Lymphoma (NHL), are not common in the literature. This study describes the rare association of these three pathologies. This is the case of a female patient with no history of hematological, neoplastic, or heart diseases, who sought the service with complaints of progressive weakness, body aches, important weight loss, and anemia. During the diagnostic investigation, protein immunoelectrophoresis showed a monoclonal peak in IgM Kappa monoclonal gammopathy, with a medullary inventory by immunophenotyping and bone marrow biopsy with Kappa+, CD19+, CD20+, CD38 and CD79b, confirming the diagnosis of mature B-cell lymphocyte neoplasm. The first line therapy chosen was dexamethasone, rituximab, and cyclophosphamide (CKD), with the latter being considered a cardiotoxic alkylating agent. At pre-chemotherapy screening, the electrocardiogram showed an alteration of the anteroseptal ventricular repolarization. Transthoracic echocardiography (ETT) showed excessive trabeculations at the apex of the left ventricle (LV), suggesting no compaction of the myocardium. The magnetic resonance imaging confirmed the diagnosis.Therapy with metoprolol and acetylsalicylic acid was started. However, after the last cycle of chemotherapy, the patient found she was pregnant (G1P1A0). The gestational and puerperium period progressed with no clinical manifestations of heart failure, in functional class I (New York Heart Association), albeit the reduction of the ejection fraction of the left ventricular shown in the transthoracic echocardiography. (AU)

Neuropatia periférica em pessoas com mieloma múltiplo / Neuropatía periférica en personas con mieloma múltiple / Peripheral neuropathy in people with multiple myeloma

Resumo Objetivo Investigar a prevalência e incidência de neuropatia periférica relacionada ao tratamento com antineoplásicos de pessoas com mieloma múltiplo bem como a associação entre os esquemas quimioterápicos e a neuropatia periférica após o tratamento. Método Estudo documental, correlacional, realizado em dois locais de referência para tratamento oncológico, localizados nos estados do Ceará e Minas Gerais, com análise de pacientes atendidos entre janeiro/2013 e janeiro/2016. Os dados foram analisados utilizando-se análise descritiva e inferencial a partir dos testes qui-quadrado e exato de fisher. Resultados Foram avaliados 100 prontuários de pessoas com mieloma múltiplo com média de idade de 62,7 anos, maioria de homens (64%). O esquema quimioterápico mais utilizado (60%) foi o bortezomibe, dexametasona e ciclofosfamida; 20% dos pacientes apresentavam neuropatia periférica antes do tratamento, 68% desenvolveram durante o tratamento e 56% ao finalizar o tratamento. Não houve associação entre os esquemas quimioterápicos e a neuropatia periférica após o tratamento. Conclusão O presente estudo mostrou um aumento da incidência de NP em indivíduos em tratamento para o MM, 80% apresentaram sintomas de neuropatia antes e/ou durante e/ou após o tratamento com esquemas quimioterápicos. A predominância foi de homens idosos aposentados. O esquema quimioterápico mais utilizado foi o VDC e não foi identificada associação entre os esquemas utilizados e a NP após término o tratamento. As implicações dessas observações recaem sobre a necessidade de avaliação contínua da NP em pessoas com MM, além da monitorização rigorosa desse evento no decorrer do tratamento e após o mesmo, bem como o manejo dos eventos adversos e alterações relacionadas a doença. Não houve associação entre os esquemas quimioterápicos e a neuropatia periférica após o tratamento. Espera-se que os resultados obtidos auxiliem na organização de um registro de dados sobre NP em pacientes com câncer, com o objetivo principal de determinar alvos de intervenção, tornando o cuidado mais eficiente e integral.

Resumen Objetivo investigar la prevalencia e incidencia de la neuropatía periférica relacionada al tratamiento con antineoplásicos de personas con mieloma múltiple, así como la asociación entre los regímenes de quimioterapia y neuropatía periférica después de tratamiento. Método Estudio documental, correlativo, realizado en dos puntos de referencia para el tratamiento del cáncer, los cuales se encuentran en los estados de Ceará y Minas Gerais, con análisis de pacientes tratados entre enero / 2013 y enero / 2016. Los datos fueron analizados utilizando el análisis descriptivo e inferencial a partir de las pruebas qui-cuadrado y exacto de Fisher. Resultados Fueron evaluados 100 expedientes de personas con mieloma múltiple con una edad media de 62,7 años, siendo la mayoría hombres (64%). El esquema quimioterápico más utilizado (60%) fue el bortezomib, dexametasona y ciclofosfamida; el 20% de los pacientes presentaban neuropatía periférica antes del tratamiento, el 68% la desarrolló durante el tratamiento y el 56% al finalizar el tratamiento. No hubo asociación entre los esquemas quimioterápicos y la neuropatía periférica después del tratamiento. Conclusión Este estudio mostró una mayor incidencia de NP en individuos que reciben tratamiento para MM, el 80% presentó síntomas de neuropatía antes y / o durante y / o después del tratamiento con regímenes de quimioterapia. La predominancia fue de hombres ancianos jubilados. El esquema quimioterápico más utilizado fue el VDC y no se identificó asociación entre los esquemas utilizados y la NP después de terminar el tratamiento. Las implicaciones de estas observaciones recaen sobre la necesidad de evaluación continua de la NP en personas con MM, además del monitoreo riguroso de dicho evento durante el tratamiento y después del mismo, así como el manejo de los eventos adversos y alteraciones relacionadas con la enfermedad. No hubo asociación entre los esquemas quimioterápicos y la neuropatía periférica después del tratamiento. Se espera que los resultados obtenidos ayuden en la organización de un registro de datos sobre NP en pacientes con cáncer, con el objetivo principal de determinar metas de intervención, obteniendo una atención más eficiente e integral.

Abstract Objective To investigate the prevalence and incidence of peripheral neuropathy (PN) related to antineoplastic therapy in people with multiple myeloma and the association between chemotherapy regimens and peripheral neuropathy after treatment. Method This is a documentary and correlational study carried out in two reference sites for cancer treatment, located in the Brazilian states of Ceará and Minas Gerais, with an analysis of patients treated between January 2013 and January 2016. A descriptive and inferential analysis of data was carried out by means of chi-square and Fischer's exact tests. Results The study assessed 100 medical records of people with multiple myeloma, who were aged 62.7 years on average and were mostly men (64%). The most used chemotherapy regimen (60%) was bortezomib, dexamethasone, and cyclophosphamide; 20% of patients had peripheral neuropathy before treatment, 68% had it during treatment and 56% at the end of treatment. There was no association between chemotherapy regimens and peripheral neuropathy after treatment. Conclusion Our study showed an increase in the incidence of PN in individuals undergoing treatment of multiple myeloma, 80% had symptoms of neuropathy before and/or during and/or after treatment with chemotherapy regimens. Predominance was of elderly retired men. The most common chemotherapy regimen was bortezomib/dexamethasone/cyclophosphamide and there was no association between regimens used and PN after treatment. The implications of these observations rest on the need for a permanent assessment of PN in people with multiple myeloma, in addition to a strict follow-up to this event in the course of treatment and after it, as well as the management of adverse events and alterations related to the disease. There was no association between chemotherapy regimens and peripheral neuropathy after treatment. It is expected that the results obtained help in the organization of a data record about PN in patients with cancer, with the main purpose of establishing targets of intervention, thus making care more efficient and comprehensive.

Genetic variants related to angiogenesis and apoptosis in patients with glioma / Variantes genéticas relacionadas à angiogênese e apoptose em pacientes com glioma

ABSTRACT Background Glioma, the most common primary malignant brain tumor in adults, is highly aggressive and associated with a poor prognosis. The objectives of this study were to evaluate the association of genetic polymorphisms related to angiogenesis and apoptosis with gliomas, as well as comorbidities, lifestyle, clinical profile, survival and response to treatment (temozolomide [TMZ] and radiotherapy [RT]) in patients with the disease. Methods In a total of 303 individuals, genotypes were performed by real-time PCR, and clinical data, lifestyle and comorbidities were obtained from medical records and questionnaires. The significance level was set at 5%. Results Smoking, alcohol consumption, systemic arterial hypertension, diabetes mellitus and body mass index prevailed among patients, compared to controls (p < 0.05). The heterozygous genotype rs1468727 (T/C) and the homozygous genotype rs2010963 (G/G) (p > 0.05) were observed in both groups. Lifestyle and comorbidities showed independent risk factors for the disease (p < 0.0001, p = 0.0069, p = 0.0394, respectively). Patients with low-grade gliomas had a survival rate of 80.0 ± 1.7% in three years. For the combination of TMZ+RT, survival was 78.7 ± 7.6% in 20 months, compared to TMZ only (21.9 ± 5.1%, p = 0.8711). Conclusions Genetic variants were not associated with gliomas. Specific lifestyle habits and comorbidities stood out as independent risk factors for the disease. Low-grade gliomas showed an increase in patient survival with TMZ+RT treatment.

RESUMO Introdução Glioma, tumor cerebral maligno, é altamente agressivo e associado a mau prognóstico. Os objetivos deste estudo foram avaliar a associação de polimorfismos genéticos relacionados a angiogênese e apoptose em pacientes com glioma, bem como suas comorbidades, hábitos de vida, perfil clínico, sobrevida e resposta ao tratamento (temozolomida [TMZ] e radioterapia [RT]). Métodos 303 indivíduos foram genotipados por PCR em tempo real, e foram coletados dados clínicos, hábitos de vida e comorbidades. Admitiu-se nível de significância para valor p < 0,05. Resultados Tabagismo, elitismo, hipertensão arterial sistêmica, diabetes mellitus e índice de massa corporal prevaleceram entre os pacientes, comprados aos controles (p < 0,05). O genótipo heterozigoto rs1468727 (T/C) e homozigoto rs2010963 (G/G) (p > 0,05) foram observados em ambos os grupos. Tabagismo, elitismo, hipertensão arterial sistêmica, diabetes mellitus e índice de massa corporal apresentaram fatores de risco independentes para a doença (p < 0.0001, p = 0.0069, p = 0.0394, respectivamente). Os pacientes com gliomas de baixo grau apresentaram sobrevida de 80,0 ± 1,7% em três anos. Para a combinação de RT e TMZ, a sobrevida foi de 78,7±7,6% em 20 meses, em comparação com TMZ (21,9 ± 5,1%, p = 0,8711). Conclusões As variantes genéticas não estiveram associadas aos gliomas. Hábitos de vida e comorbidades específicas destacaram-se como fatores de risco independentes para a doença. O tratamento com TMZ + RT mostrou aumento na sobrevida dos pacientes.

The therapeutic effects of curcumin and capsaicin against cyclophosphamide side effects on the uterus in rats

Abstract Purpose: To evaluate the impact of systemic cyclophosphamide treatment on the rat uterus and investigate the potential therapeutic effects of natural antioxidant preparations curcumin and capsaicin against cyclophosphamide side effects. Methods: A 40 healthy adult female Wistar albino rats were used in this study. Rats were randomly divided into four groups to determine the effects of curcumin and capsaicin against Cyclophosphamide side effects on the uterus (n=10 in each group); Group 1 was the control group (sham-operated), Group 2 was the cyclophosphamide group, Group 3 was the cyclophosphamide + curcumin (100mg/kg) group, and Group 4 was the cyclophosphamide + capsaicin (0.5 mg/kg) group. Results: Increased tissue oxidative stress and histological damage in the rat uterus were demonstrated due to the treatment of systemic cyclophosphamide chemotherapy alone. The level of tissue oxidant and antioxidant markers and histopathological changes were improved by the treatment of curcumin and capsaicin. Conclusion: Cytotoxic effects of natural alkylating chemotherapeutic agents like cyclophosphamide on the uterus can be prevented by curcumin and capsaicin.

Triptolide induces oxidative stress and apoptosis and activates PIK3/Akt signaling pathway in TM4 sertoli cells / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effect of triptolide (TP) on oxidative stress and apoptosis in TM4 sertoli cells and related molecular mechanism.@*METHODS@#TM4 cells were incubated with different concentrations of triptolide for 24 h, then collected for further experiments. Cell proliferation analysis was used to measure the inhibitive effect of triptolide on proliferation of TM4 cells; DCFH-DA (6-carboxy-2',7'-dichlorofluorescein diacetate) probe was used to stain the TM4 cells, the level change of intracellular ROS was discovered through flow cytometry; the TM4 cells were stained by Annexin V-FITC/PI to detect whether triptolide induced apoptosis in the TM4 cells; Protein was extracted from the TM4 cells in control and triptolide group. Western blot was performed to determine the expression of apoptosis marker protein cleaved-PARP and PI3K/Akt signaling pathway-related proteins [p-Akt (Ser473), Akt, p-mTOR (Ser2448), mTOR, p-p70S6K (Thr389), p70S6K].@*RESULTS@#Cell proliferation analysis revealed that triptolide reduced the TM4 cells viability significantly compared with control group in a dosage-dependent manner [10 nmol/L: (73.77±20.95)%, 100 nmol/L: (51.60±10.43)%, 500 nmol/L: (44.34±5.78)%]; The level of intracellular ROS in the TM4 cells was significantly induced in a dosage-dependent manner (P<0.01); triptolide remarkably induced early-stage and late-stage apoptosis in the TM4 cells [control: (3.84±1.50)%, 100 nmol/L: (13.04±2.03)%, 200 nmol/L: (16.24±1.34)%, 400 nmol/L: (18.76±3.45)%]; The expression of cleaved-PARP was significantly upregulated in the TM4 cells after incubation with triptolide (P<0.01); The expression levels of p-Akt/Akt and p-p70S6K/p70s6k were significantly increased compared with control group (P<0.01). No significant change was observed among the expression levels of p-mTOR/mTOR (P>0.05).@*CONCLUSION@#In vitro studies showed that triptolide could effectively suppress the proliferation and induce apoptosis of TM4 sertoli cells. The oxidative stress was upregulated after incubation with triptolide, which may be one of the mechanisms of cytotoxicity in TM4 cells. Treatment of triptolide led to activation of Akt and p70S6K, indicating that the PI3K/Akt signaling pathway may be involved in response to oxidative stress in TM4 cells. The activation of PI3K/Akt signaling pathway was one of the molecular mechanisms involved in triptolide-mediated oxidative stress in TM4 cells. Our study provides insight into alleviating reproductive toxicity of triptolide in clinical and developing male contraceptive.

Hepatotoxicidad colestásica asociada al uso de quimioterapia en esquema con lomustina: reporte de un caso y revisión de la literatura / Colestasic hepatotoxicity associated with the use of chemotherapy in scheme with lomustine: case report and literature review

Drug-induced liver injury (DILI) is a rare entity associated with high morbidity and mortality. It includes a broad spectrum of clinical patterns, from acute hepatitis to cirrhosis. Among the common associated drugs are antimicrobial like anti-TBC, antineoplastic, CNS agents and non-steroidal anti-inflammatory drugs. Establishing causality between DILI and a certain drug is a challenge. Some scoring systems have been evaluated, considering RUCAM score as the gold standard. We present the case of a 35-year-old woman with a history of a high-grade glioma treated with surgery and chemotherapy with lomustine, procarbazine and vincristine. She evolved with altered liver tests, predominantly cholestatic pattern, but asymptomatic. Etiologic study negative and abdominal imaging were normal. The liver biopsy was compatible with 40% ductopenia, without inflammatory elements. We consider DILI associated with the use of lomustine, with RUCAM score suggesting. After discontinuing chemotherapy and using ursodeoxycholic acid for the treatment of cholestasis there was an improvement in liver tests. There is limited evidence in the literature regarding hepatotoxicity associated with lomustine, mainly in experimental animal models. Cases of cholestatic hepatotoxicity have been described with the use of other similar nitrosureas. In relation to procarbazine and vincristine, DILI is reported mainly reversible and predominantly with hepatocellular pattern, not consistent with our case. We find it interesting to communicate with review of the literature about it.

El daño hepático inducido por drogas (DILI) es una entidad poco frecuente, con alta morbimortalidad asociada. Incluye un amplio espectro de patrones clínicos, desde hepatitis aguda a cirrosis. Dentro de los fármacos frecuentemente asociados se encuentran antibióticos como anti-TBC, agentes antineoplásicos, de acción en el SNC y anti-inflamatorios no esteroidales. Establecer una causalidad entre DILI y una determinada droga constituye un desafío. Para ello, se han evaluado diversos sistemas de puntuación, considerándose gold estándar el RUCAM score. Se presenta el caso de una mujer de 35 años de edad con antecedentes de glioma de alto grado operado y en quimioterapia con lomustina, procarbazina y vincristina. En su evolución presenta alteración de pruebas hepáticas de predominio colestásico de manera asintomática, con estudio etiológico causal negativo e imagenológico normal. La biopsia hepática fue compatible con ductopenia de 40% sin elementos inflamatorios. Se plantea DILI asociado al uso de lomustina con un score de RUCAM sugerente, decidiéndose interrumpir sus ciclos de quimioterapia e inicia tratamiento con ácido ursodesoxicólico, presentando mejoría progresiva de pruebas hepáticas. Existe evidencia limitada en la literatura en relación a hepatotoxicidad asociada a este fármaco, principalmente en modelos experimentales, y con el uso de otras nitrosureas similares se han descrito casos de hepatotoxicidad de predominio colestásico. En relación con procarbazina y vincristina existen reportes de DILI principalmente reversible y con patrón de predominio hepatocelular, lo que no es concordante con nuestro caso, por lo cual nos parece de interés comunicarlo con revisión de la literatura al respecto.

Antral Follicles Count and Anti-Müllerian Hormone Levels after Gonadotoxic Chemotherapy in Patients with Breast Cancer: Cohort Study / Contagem de folículos antrais e níveis de hormônio anti-Mülleriano após quimioterapia gonadotóxica em pacientes com câncer de mama: estudo de coorte

Abstract Aim To assess ovarian reserve (OVR) by means of follicle-stimulating hormone (FSH), anti-Müllerian hormone (AMH), and antral follicle count (AFC) measurement in eumenorrheic women with breast cancer, exposed to gonadotoxic chemotherapy. Method Fifty-two women (35.3 ± 3.8 years old) with breast cancer and undergoing cyclophosphamide-containing chemotherapy were enrolled. The assessment was performed before chemotherapy (T1) and after 2 (T2) and 6 months (T3). Results Six months after chemotherapy, the prevalence of regular cycles was 60%. Anti-Müllerian hormone decreased down to undetectable levels at T2 and T3 (T1: 2.53 [1.00–5.31]; T2 < 0.08; T3: < 0.08 [< 0.08–1.07] ng/mL), (p< 0.0001). Antral follicle count was 11 [8.0–13.5] follicles at T1 and lower at T2 (5.50 [3.75–8.0] and T3 (5.0 [2.5–7.0]) (p< 0.0001). In patients who remained with regular cycles during chemotherapy or resumed normal menses, FSH and estradiol levels remained unchanged. Conclusion Anti-Müllerian hormone and AFC are useful as markers of OVR decline in women exposed to chemotherapy. Follicle-stimulating hormone is only adequate in women who become amenorrheic.

Resumo Objetivo Avaliar a reserva ovariana (OVR) através da contagem de folículos antrais (AFC), dosagem sérica de hormônio folículo estimulante (FSH) e hormônio anti-Mülleriano (AMH) em mulheres com câncer de mama submetidas a quimioterapia gonadotóxica. Método Foram incluídas na pesquisa 52 mulheres (35,3 ± 3,8 anos) com câncer de mama, em tratamento com quimioterapia com ciclofosfamida. As dosagens e medidas foram realizadas antes do início da quimioterapia (T1) e após 2 (T2) e 6 meses (T3). Resultados Seis meses após quimioterapia, a prevalência de ciclos regulares foi de 60%. O AMH sérico diminuiu a níveis indetectáveis em T2 e T3 (T1: 2,53 [1,00–5,31] ]; T2 < 0,08; T3: < 0,08 [< 0,08–1,07] ng/mL) (p< 0,0001). A contagem de folículos antrais foi de 11 [8,0–13,5] folículos em T1, e ainda menor em T2 (5,50 [3,75–8,0] e T3 (5,0 [2,5–7,0]), (p< 0,0001). Em pacientes que mantiveram ciclos regulares durante a quimioterapia ou retomaram a menstruação normalmente, os níveis de FSH e estradiol permaneceram inalterados. Conclusão O AMH e a AFC são marcadores úteis do declínio da OVR em mulheres expostas à quimioterapia. O FSH só é adequado em mulheres que se tornam amenorreicas.

Eficacia y seguridad de bevacizumab en eltratamiento del glioblastoma multiforme recurrente, irresecable y terapia previa con temozolamida / Efficacy and safety of bevacizumab in the treatment of recurrent, unresectable glioblastoma multiforme and previous therapy with temozolamide

INTRODUCCIÓN: Antecedentes: El Instituto de Evaluación de Tecnologías en Salud e Investigación (IETSI) ha recibido la solicitud de evaluar el uso de bevacizumab (BVZ) e irinotecan en pacientes adultos con diagnóstico de glioblastoma multiforme recurrente, irresecable que progresaron a temozolamida dentro del sistema de EsSalud, indicación actualmente no contemplada en el petitorio de medicamentos. Aspectos Generales: Los gliomas son el tipo más común de tumores cerebrales malignos. Ellos se desarrollan a partir de las células gliales que dan apoyo a las células nerviosas del cerebro y medula espinal. Existen cuatro tipos principales de gliomas: astrocitoma, ependimoma, oligliodendroglioma, y tumores mixtos. Los gliomas son clasificados de acuerdo a su 1.) potencial de proliferación ascendente, desde el grado 1 al grado 4. Los gliomas de grado 3 y 4 son conjuntamente referidos con glioblastomas, y son considerados como gliomas de alto grado. El glioma de grado 4 es llamado glioblastoma multiforme. Los síntomas del glioma de alto grado dependen del tamaño, la localización, y el grado de infiltración del tumor. Ellos incluyen dolor de cabeza, náuseas, vómitos, convulsiones, aIteración de la visión, problemas del lenguaje y cambios en las habilidades cognitivas o funcionales. Tecnología Sanitaria de Interés: Bevacizumab (Avastin, Roche) es un anticuerpo monoclonal anti-factor de crecimiento endotelial vascular (VEGF), que inhibe la inducción de la angiogénesis mediada por el VEGF. En consecuencia, se reduce la vascularización de los tumores, y también del crecimiento del mismo. METODOLOGIA: Estratégia de Busqueda: Se realizó una búsqueda de la literatura con respecto a la eficacia y seguridad del uso de BVZ en comparación con irinotecan, en el tratamiento del GBM con recurrencia o progresión, irresecable durante el tratamiento coadyuvante con TMZ, en las bases de \r\ndatos de MEDLINE, EMBASE, CENTRAL, DARE y TRIPDATABASE. Se hizo una búsqueda adicional en www.clinicaltrials.gov, para poder identificar ensayos clínicos aún en elaboración o que no hayan sido publicados. Adicionalmente, se hizo una búsqueda dentro de la información generada por las principales instituciones internacionales oncológicas y agencias de tecnologías sanitarias que realizan revisiones sistemáticas (RS), evaluación de tecnologías sanitarias (ETS) y guías de práctica clínica (GPC).\r\nRESULTADOS: Sinopsis de la Evidencia: Se realizó la búsqueda bibliográfica y de evidencia científica que sustente el uso de BVZ en comparación con irinotecan, en el tratamiento del GBM con recurrencia o progresión, irresecable durante el tratamiento adyuvante con TMZ según la pregunta PICO. Para el \r\npresente documento se seleccionó el siguiente cuerpo de evidencia que es resumido a continuación.Guías Clínicas: Se identificaron cuatro GPC sobre el manejo del glioblastoma recurrente. Evaluaciones de tecnología sanitaria: no se identificaron documentos de ETS para el uso de bevacizumab en el GBM recurrente. Se identificó una evaluación planeada por NICE, la cual fue retirada después de conocer la decisión de la EMA de no aprobar el uso de BVZ para la indicación de GBM recurrente. Revisiones sistemáticas: no se identificó alguna revisión sistemática que haya evaluado el uso de BVZ en comparación con el de irinotecan en pacientes con GBM recurrente. Ensayos clínicos: no se identificó algún ensayo que haya comparado el uso de BVZ con el tratamiento con irinotecan. En su lugar, se identificaron y se han incluido en esta evaluación tres ensayos. Uno de fase II no comparativo que usó BVZ, y otros dos estudios \r\nde fase II aleatorizados que compararon los efectos de BVZ con el régimen de BVZ + irinotecan. Este tipo de evidencia es considerada como indirecta por no responder directamente a la pregunta PICO de esta evaluación. Ensayos Clínicos registrados: no se identificaron ensayos en progreso o aun sin publicar que puedan agregar información a la pregunta PICO de esta evaluación. CONCLUSIONES: Hasta el momento, no se ha identificado evidencia directa para responder si el uso de BVZ es más efectivo y seguro que irinotecan en el tratamiento de los pacientes con GBM recurrente, irresecable y que progresó con el uso de TMZ. Hasta la fecha no se ha identificado algún estudio que haya comparado directamente ambos medicamentos.

Are we following the guidelines on non-muscle invasive bladder cancer?

ABSTRACT Objectives To evaluate the clinical practice of non-muscle invasive bladder cancer (NMIBC) treatment in Brazil in relation to international guidelines: Sociedade Brasileira de Urologia (SBU), European Association of Urology (EAU) and American Urological Association (AUA). Materials and Methods Cross-sectional study using questionnaires about urological practice on treatment of NMIBC during the 32nd Brazilian Congress of Urology. A total of 650 question forms were answered. Results There were 73% of complete answers (total of 476 question forms). In total, 246 urologists (51.68%) lived in the southeast region and 310 (65.13%) treat 1 to 3 cases of NMIBC per month. Low risk cancer: Only 35 urologists (7.5%) apply the single intravesical dose of immediate chemotherapy with Mitomicin C recommended by the above guidelines. Adjuvant therapy with BCG 2 to 4 weeks after TUR is used by 167 participants (35.1%) and 271 urologists (56.9%) use only TUR. High risk tumors: 397 urologists (83.4%) use adjuvant therapy, 375 (78.8%) use BCG 2 to 4 weeks after TUR, of which 306 (64.3%) referred the use for at least one year. Intravesical chemotherapy with Mitomicin C (a controversial recommendation) was used by 22 urologists (4.6%). BCG dose raised a lot of discrepancies. Induction doses of 40, 80 and 120mg were referred by 105 (22%), 193 (40.4%) and 54 (11.3%) respectively. Maintenance doses of 40, 80 and 120mg were referred by 190 (48.7%), 144 (37.0%) and 32 (8.2%) urologists, respectively. Schemes of administration were also varied and the one cited by SWOG protocol was the most used: 142 (29.8%). Conclusion SBU, EAU and AUA guidelines are partially respected by Brazilian urologists, particularly in low risk tumors. In high risk tumors, concordance rates are comparable to international data. Further studies are necessary to fully understand the reasons of such disagreement.

Validation of the Effectiveness and Safety of Temozolomide during and after Radiotherapy for Newly Diagnosed Glioblastomas: 10-year Experience of a Single Institution

This study was performed to validate the effectiveness and safety of concurrent chemoradiotherapy and adjuvant therapy with temozolomide for newly diagnosed glioblastoma multiforme as a standard treatment protocol. Between 2004 and 2011, patients newly diagnosed with glioblastoma who were treated with temozolomide during concurrent chemoradiotherapy and adjuvant chemotherapy were included from a single institution and analyzed retrospectively. The primary endpoint was overall survival, and the secondary endpoints were progression-free survival, response, and safety. A total of 71 patients were enrolled in this study. The response rate was 41% (29/71), and the tumor control rate was 80% (57/71). In the 67 patients who completed the concurrent chemoradiotherapy with temozolomide, the median overall survival was 19 months and the 1- and 2-yr overall survival rates were 78.3% and 41.7%, respectively. The median progression free survival was 9 months, and the 1- and 2-yr progression free survival rates were 33.8% and 14.3%, respectively. The mean duration of survival after progression of disease in salvage treatment group was 11.9 (1.3-53.2) months. Concurrent chemoradiotherapy with temozolomide resulted in grade 3 or 4 hematologic toxic effects in 2.8% of the patients. The current protocol of temozolomide during and after radiation therapy is both effective and safe and is still appropriate as the standard protocol for treatment of glioblastoma. An active salvage treatment might be required for a better prognosis.

Trabectedin therapy as an emerging treatment strategy for recurrent platinum-sensitive ovarian cancer / 癌症

Epithelial ovarian cancer (OC) is a common gynecologic malignancy in women. The standard treatment for OC is maximal cytoreductive surgical debulking followed by platinum-based chemotherapy. Despite the high response rate to primary therapy, approximately 85% of patients will develop recurrent ovarian cancer (ROC). This review identifies the clinical use of trabectedin in the treatment algorithm for ROC, with specific emphasis on platinum-sensitive ROC, for which trabectedin in combination with pegylated liposomal doxorubicin has been approved as a treatment protocol. The main mechanisms of action of trabectedin at the cellular level and in the tumor microenvironment is also discussed as bases for identifying biomarkers for selecting patients who may largely benefit from trabectedin-based therapies.

Pleurotus nebrodensis polysaccharide (PN-S) enhances the immunity of immunosuppressed mice / 中国天然药物

In the present study, the effects of Pleurotus nebrodensis polysaccharide (PN-S) on the immune functions of immunosuppressed mice were determined. The immunosuppressed mouse model was established by treating the mice with cyclophosphamide (40 mg/kg/2d, CY) through intraperitoneal injection. The results showed that PN-S administration significantly reversed the CY-induced weight loss, increased the thymic and splenic indices, and promoted proliferation of T lymphocyte, B lymphocyte, and macrophages. PN-S also enhanced the activity of natural killer cells and increased the immunoglobulin M (IgM) and immunoglobulin G (IgG) levels in the serum. In addition, PN-S treatment significantly increased the phagocytic activity of mouse peritoneal macrophages. PN-S also increased the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), and nitric oxide (NOS) in splenocytes. qRT-PCR results also indicated that PN-S increased the mRNA expression of IL-6, TNF-α, INF-γ, and nitric oxide synthase (iNOS) in the splenocytes. These results suggest that PN-S treatment enhances the immune function of immunosuppressed mice. This study may provide a basis for the application of this fungus in adjacent immunopotentiating therapy against cancer and in the treatment of chemotherapy-induced immunosuppression.

Prediction of Response to Concurrent Chemoradiotherapy with Temozolomide in Glioblastoma: Application of Immediate Post-Operative Dynamic Susceptibility Contrast and Diffusion-Weighted MR Imaging

OBJECTIVE: To determine whether histogram values of the normalized apparent diffusion coefficient (nADC) and normalized cerebral blood volume (nCBV) maps obtained in contrast-enhancing lesions detected on immediate post-operative MR imaging can be used to predict the patient response to concurrent chemoradiotherapy (CCRT) with temozolomide (TMZ). MATERIALS AND METHODS: Twenty-four patients with GBM who had shown measurable contrast enhancement on immediate post-operative MR imaging and had subsequently undergone CCRT with TMZ were retrospectively analyzed. The corresponding histogram parameters of nCBV and nADC maps for measurable contrast-enhancing lesions were calculated. Patient groups with progression (n = 11) and non-progression (n = 13) at one year after the operation were identified, and the histogram parameters were compared between the two groups. Receiver operating characteristic (ROC) analysis was used to determine the best cutoff value for predicting progression. Progression-free survival (PFS) was determined with the Kaplan-Meier method and the log-rank test. RESULTS: The 99th percentile of the cumulative nCBV histogram (nCBV C99) on immediate post-operative MR imaging was a significant predictor of one-year progression (p = 0.033). ROC analysis showed that the best cutoff value for predicting progression after CCRT was 5.537 (sensitivity and specificity were 72.7% and 76.9%, respectively). The patients with an nCBV C99 of < 5.537 had a significantly longer PFS than those with an nCBV C99 of ≥ 5.537 (p = 0.026). CONCLUSION: The nCBV C99 from the cumulative histogram analysis of the nCBV from immediate post-operative MR imaging may be feasible for predicting glioblastoma response to CCRT with TMZ.

DNMT1 mediates chemosensitivity by reducing methylation of miRNA-20a promoter in glioma cells

Although methyltransferase has been recognized as a major element that governs the epigenetic regulation of the genome during temozolomide (TMZ) chemotherapy in glioblastoma multiforme (GBM) patients, its regulatory effect on glioblastoma chemoresistance has not been well defined. This study investigated whether DNA methyltransferase (DNMT) expression was associated with TMZ sensitivity in glioma cells and elucidated the underlying mechanism. DNMT expression was analyzed by western blotting. miR-20a promoter methylation was evaluated by methylation-specific PCR. Cell viability and apoptosis were assessed using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and TdT-mediated dUTP-biotin nick end labeling assays, respectively. The results showed that compared with parental U251 cells, DNMT1 expression was downregulated, miR-20a promoter methylation was attenuated and miR-20a levels were elevated in TMZ-resistant U251 cells. Methyltransferase inhibition by 5-aza-2\'-deoxycytidine treatment reduced TMZ sensitivity in U251 cells. In U251/TM cells, DNMT1 expression was negatively correlated with miR-20a expression and positively correlated with TMZ sensitivity and leucine-rich repeats and immunoglobulin-like domains 1 expression; these effects were reversed by changes in miR-20a expression. DNMT1 overexpression induced an increase in U251/TM cell apoptosis that was inhibited by the miR-20a mimic, whereas DNMT1 silencing attenuated U251/TM cell apoptosis in a manner that was abrogated by miR-20a inhibitor treatment. Tumor growth of the U251/TM xenograft was inhibited by pcDNA-DNMT1 pretreatment and boosted by DNMT1-small hairpin RNA pretreatment. In summary, DNMT1 mediated chemosensitivity by reducing methylation of the microRNA-20a promoter in glioma cells.