A mucosite bucal está entre as principais complicações decorrentes do tratamento antineoplásico em pacientes com leucemia linfóide aguda (LLA). Entre os fatores de risco para sua ocorrência destacam-se a idade, o gênero e a leucometria inicial, além das drogas quimioterápicas com comprovada ação estomatotóxicas. O objetivo deste estudo foi investigar a prevalência e os fatores de risco para a mucosite bucal em pacientes com LLA submetidos a diferentes protocolos de tratamento quimioterápicos. Um total de 169 prontuários clínicos de pacientes oncológicos pediátricos submetidos a diferentes protocolos de tratamento para LLA no Setor de Oncologia Pediátrica do Hospital Infantil Darcy Vargas, na cidade de São Paulo, no período compreendido entre 1994 a 2005 foram, retrospectivamente, avaliados. Os dados demográficos (idade e gênero) e clínicos (leucometria inicial, protocolo de tratamento a que foi submetido, evolução, ocorrência de mucosite e outras lesões bucais) foram registrados. A associação da mucosite bucal com as variáveis clínicas e demográficas foi obtida pelos testes do qui-quadrado e análise de regressão logística multivariada. Os resultados demonstraram uma freqüência de mucosite bucal em 46% dos pacientes oncológicos pediátricos com LLA sem correlação estatisticamente significativa entre sua ocorrência e o gênero (p=0,08), a idade (p=0,33) e a leucometria inicial (p=0,34). Na análise multivariada o protocolo de tratamento do grupo Berlim- Frankfurt-Munique de 1995 (ALL-BFM 95), de acordo com as variáveis avaliadas neste estudo, mostrou ser o fator mais significativo (p=0,009) para a ocorrência da mucosite bucal. Esses resultados fortemente sugerem uma maior estomatotoxicidade do protocolo ALL-BFM 95 comprovadas pela maior freqüência de mucosite bucal nos pacientes ontológicos pediátricos com LLA. Portanto, concluímos que a mucosite bucal deveria ser sistematicamente analisada nos centros especializados no tratamento da LLA que adotam diferentes protocolos de tratamento, visando não somente contribuir com a análise do grau de toxicidade das drogas quimioterápicas, mas principalmente, melhorar a qualidade de vida do paciente com base em condutas terapêuticas e profiláticas mais efetivas na prevenção de sua ocorrência. / Oral mucositis is one of the main complications secondary to antineoplastic treatment in patients with acute lymphoblastic leukemia (ALL). The risk factors for its occurrence include age, gender and initial leukocyte count, besides chemotherapeutic drugs with known stomatotoxic action. This study investigated the prevalence and risk factors to oral mucositis in patients with ALL submitted to different chemotherapeutic treatment protocols. A total of 169 clinical records of pediatric oncology patients submitted to different treatment protocols for ALL at the Pediatric Oncology Sector of the Child Hospital Darcy Vargas, in the city of São Paulo, in the period 1994 to 2005 were retrospectively evaluated. Demographic (age and gender) and clinical data (initial leukocyte count, treatment protocol adopted, evolution, occurrence of mucositis and other oral lesions) were recorded. The association of oral mucositis with the clinical and demographic variables was assessed by the chi-square test and multivariate logistic regression analysis. The results demonstrated occurrence of oral mucositis in 46% of pediatric oncology patients with ALL, without statistically significant correlation between its occurrence and gender (p=0.08), age (p=0.33) and initial leukocyte count (p=0.34). Multivariate analysis revealed that the Berlin-Frankfurt-Munich protocol of 1995 (ALL-BFM 95) was the most significant factor (p=0.009) to the occurrence of oral mucositis according to the variables evaluated in this study. These results strongly suggest the greater stomatotoxic effect of the ALL-BFM 95 protocol, as demonstrated by the higher frequency of oral mucositis in pediatric oncology patients with ALL. Thus, it may be concluded that oral mucositis should be systematically analyzed in centers specialized in the treatment of ALL adopting different treatment protocols, with a view to contribute to analysis of the degree of toxicity of chemotherapeutic drugs and mainly to improve the quality of life of patients on the basis of more effective therapeutic and prophylactic approaches for prevention of its occurrence.

A enzima L-asparaginase (ASNase) usada como biofármaco no tratamento de Leucemia Linfoblástica Aguda (LLA) é de origem bacteriana, o que provoca reações imunológicas nos paciente e a ASNase usada no Brasil é importada o que dificulta seu uso por razões de abastecimento e de preço. Por outra parte, dentro dos sistemas de expressão de proteínas recombinantes usados pela biotecnologia, destaca-se a Pichia pastoris, levedura metilotrófica de fácil manipulação, crescimento rápido, alta capacidade de expressão e capaz de realizar modificações pós-traducionais. Neste projeto, o gene de ASNase II de Saccharomyces cerevisiae foi expressa em P. pastoris (Muts), tendo sido analisada a localização da enzima nos meios extracelular, intracelular e espaço periplasmático. Além disso, foram avaliadas diversas condições de crescimento e indução da ASNase em agitador orbital e finalmente foi feito o cultivo em biorreator de 3L operado em batelada. Segundo o analise da expressão, a enzima foi localizada no espaço periplasmático. O crescimento de P. pastoris em diferentes concentrações de glicerol (10,0 - 50,0 g.L-1) mostraram parâmetros cinéticos similares (µmáx = 0,35 h-1; tg= 2,0 h) e o maior fator de conversão de substrato em células (Y x/s = 0,9 g g-1) foi obtido com 10,0 g.L-1 de glicerol. A expressão de ASNase somente ocorreu a 20 °C e melhora com concentrações de metanol acima de 1,0% (v/v), obtendo-se a maior produção da enzima a 3% de metanol durante 48 horas, o que foi corroborado pelo planejamento fatorial fraccionado (3n-k + 2), n = 3 e k =1. Também se observou que o pH de indução, a suplementação com aminoácidos ou casaminoácidos e concentração de glicerol durante a fase de crescimento apresentaram pouca ou nenhuma influência na expressão. Entretanto, as células induzidas imediatamente após o glicerol ter sido consumido melhoraram a produção de ASNase. No cultivo em biorreator, a fase de crescimento foi feita com 10,0 e 40,0 g.L-1-1 de glicerol, e a fase de indução com pulsos de 3,0% (v/v) de metanol durante 120 horas. A maior atividade volumétrica (710,2 U.L-1) de ASNase foi obtida na batelada com 40,0 g.L-1 de glicerol e a atividade periplasmática foi constante durante o tempo de cultivo o que significa que o controle do pH afeta positivamente na expressão de ASNase. / The bacterial L-asparaginase (ASNase) is used as biopharmaceutical in the treatment of acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma and because his origin causes immune reactions in patients. The ASNase used in Brazil is imported which hinders its use due to supply availability and price. The methylotrophic yeast Pichia pastoris, is a microrganism easy to handle and with fast growth and high capacity of expression of recombinant proteins and that is able to carry out post-translational modifications. In this work, Saccharomyces cerevisiae ASNase II gene was expressed in Pichia pastoris (Muts) and was analyzed its localization in extra and intracellular medium and periplasmic space. Also, different conditions of growth and induction were evaluated in shaker, that culminated in a cultivation carried out in 3L bioreactor operated in batch. According the expression analysis, the enzyme was localized in periplasmic space; Pichia pastoris growth in different concentrations of glycerol (10 - 50 g.L-1) show similar kinetic parameters (µmáx = 0.35 h-1; tg = 2.0 h), with the higher substrate to biomass yield (Y x/s= 0.9 g.g-1) obtained with 10 g.L-1 of glycerol. The ASNase expression only occurred at 20°C and improves with methanol concentrations above 1.0% (v/v) to yield the highest production ASNase 3.0% methanol for 48 hours, which was corroborated by factorial fractionated design (3n-k + 2), n = 3 and k = 1. Also was observed that the pH of induction, supplementation with amino acids or casaminoacids and glycerol concentration during the growth phase had little or null influence on the expression. However the induction immediately after glycerol depletion improved the ASNase production. In bioreactor, were used 10 and 40 g.L-1 of glycerol in the growth phase and in the induction phase were used methanol pulses of 3.0% (v/v) during 120 hours. The major volumetric activity (710,2 U.L-1) of ASNase occurred in batch cultivation with 40 g.L-1 of glycerol and periplasmic activity was almost constant during the process which means that the control of pH affects positively the ASNase expression.

A L-asparaginase (EC 3.5.1.1) é uma enzima importante para o tratamento da leucemia linfoblástica aguda (LLA), neoplasia mais frequente em crianças e adolescentes. A L-asparaginase hidrolisa a L-asparagina resultando em ácido aspártico e amônio, impedindo que as células tumorais utilizem esse aminoácido para síntese proteica, ocasionando a morte celular apoptótica. Atualmente a enzima é obtida a partir de Escherichia coli e Erwinia chrysanthemi; no entanto, ambas as formulações estão associadas a um alto índice de efeitos adversos que comprometem a evolução e eficácia do tratamento. A levedura Saccharomyces cerevisiae tem o gene ASP1 responsável pela produção de L-asparaginase 1 (Sc_ASPase1) que tem sido pouco estudada. Para elucidar as características de Sc_ASPase1 nós expressamos a proteína em E. coli BL21(DE3) e a purificamos por cromatografia de afinidade. Sc_ASPase1 tem uma atividade especifica de 195,4 U/mg para L-asparagina e de 0,36 U/mg para L-glutamina, e um comportamento alostérico com um K0.5 de 75 µM para L-asparagina. Por meio de mutação sitio dirigida demonstramos a importância dos resíduos Thr64-Thy78-Th141-Lys215 para a catálise. As isoformas mutantes da proteína A331D, K335E, Y243S, S301N e ΔG77 não apresentaram melhoria nos parâmetros cinéticos ou atividade específica. Construímos e clonamos Sc_ASPase1 com a deleção dos primeiros 52 aminoácidos, porém nas condições testadas a proteína foi expressa na forma insolúvel. Demonstramos que Sc_ASPase1 possui potencial antineoplásico, pois com 10 U/mL de enzima foi capaz causar a 85% de mortalidade da linhagem leucêmica MOLT-4. Na mesma concentração, a enzima de E. coli é capaz de matar 95% de células dessa mesma linhagem. / L-Asparaginase (EC 3.5.1.1) is an important enzyme for the treatment of acute lymphoblastic leukemia (ALL), the most common malignancy in children and adolescents. L-asparaginase hydrolyzes L-asparagine resulting in ammonium and aspartic acid, preventing tumor cells of using such amino acid for protein synthesis, leading to apoptotic cell death. Currently, the enzyme is obtained from Escherichia coli and Erwinia chrysanthemi; however, both formulations are associated with a high incidence of side effects that compromise the progress and effectiveness of treatment. The yeast Saccharomyces cerevisiae has ASP1 gene responsible for the production of L-asparaginase 1 (Sc_ASPase1) that has been poor studied. To elucidate the characteristics of Sc_ASPase1, we expressed the protein in E. coli BL21 (DE3) cells and purified it by affinity chromatography. Sc_ASPase1 has a specific activity of 195.4 U/mg for L-asparagine and 0.36 U/mg for L-glutamine, and an allosteric behavior with a K0.5 of 75 µM for L-asparagine. Through site directed mutation, we demonstrated the importance of Thr64-Thy78-Th141-Lys215 residues for catalysis. The mutant protein isoforms A331D, K335E, Y243S, S301N and ΔG77 showed no improvement in kinetic parameters or specific activity. We build and cloned Sc_ASPase1 with the deletion of the first 52 amino acids, but under the conditions tested the protein was expressed in insoluble form. Sc_ASPase1 have demonstrated potential antineoplastic activityc, since 10 U/mL of enzyme lead to 85% of mortality in leukemia cell line MOLT-4. At the same concentration, the E. coli enzyme kills 95% of the cells of the same line.

Made available in DSpace on 2016-08-19T18:16:06Z (GMT). No. of bitstreams: 1 DISSERTACAO KARLA.pdf: 550872 bytes, checksum: a1efbaeab3d76483b6e7b53d97cc5a68 (MD5) Previous issue date: 2012-09-28 / The acute lymphoblastic leukemia (ALL) is characterized by abnormal proliferation of immature lymphoid cells and represents the most common cancer in children. The evaluation of prognostic factors in patients with ALL enables the implantation of different therapeutic approaches. The aberrant expression of markers CD56, CD57 and CD16 may be a way to assess this prognosis. The objective of this study was to characterize patients with ALL and to evaluate the prognostic influence of aberrant expression of markers CD56, CD16 and CD57 in ALL. 44 patients treated at the Maranhense Oncology Institute Aldenora Bello in Sao Luis - MA were evaluated, from March 2010 to October 2011. Patients were diagnosed with ALL according to the morpho-cytochemical and immunophenotype criteria. The expression of markers was determined by flow cytometry and clinical data were obtained through chart review. Two groups were divided as the expression or not of these markers and compared in relation to prognostic variables. The average of age in the sample was 6,28 years, with a predominance of males (60,0%). The average of blasts counted in bone marrow (BM) and peripheral blood (PB) was 77,0 and 39,6, respectively. The L1 morphology of the blasts from BM was the most frequent (80,0%). The profile of the blood count at diagnosis indicated: 24.061 leukocytes/mm3; 56.510 platelets/mm3 and 8,0 g/dL hemoglobin. According to the classification GBTLI-99, 60,0% of the patients were in low risk of recurrence group and in the end of the induction phase of treatment (D29), 70,0% of the patients had remission. The patients with ALL T had mean of age (10,6 years; p = 0,0204) and leukometry (48.200/mm3; p = 0,0167) significantly higher than patients with ALL B. 80,0% of the patients expressed the CD56 marker and no patient expressed CD16 and/or CD57 markers. Patients who did not express the marker CD56 had age significantly higher those who expressed (9,3 years; p = 0,0353). For patients with ALL B, the average of blasts from PB of patients who expressed the CD56 marker was higher than those not expressed (41,1; p = 0,0226). It is concluded that CD56 expression characterizes a worse prognosis for patients with ALL B, due to a significantly higher average of blasts counted in PB found in our study. However, a greater number of cases and a longer observation time would be needed to better emphasize this evidence. / A Leucemia linfóide aguda (LLA) é caracterizada pela proliferação anormal de células linfóides imaturas e representa a neoplasia mais comum em crianças. A avaliação de fatores prognósticos em pacientes com LLA possibilita a implantação de abordagens terapêuticas diferenciadas. A expressão aberrante dos marcadores CD56, CD57 e CD16 pode ser uma forma de avaliar tal prognóstico. O objetivo deste trabalho foi caracterizar os pacientes com LLA e avaliar a influência prognóstica da expressão aberrante dos marcadores CD56, CD16 e CD57 na LLA. Foram avaliados 40 pacientes, atendidos no Instituto Maranhense de Oncologia Aldenora Bello (IMOAB), em São Luís MA, no período de março de 2010 a outubro de 2011. Os pacientes foram diagnosticados com LLA, segundo os critérios morfo-citoquímicos e imunofenotípicos. A expressão dos marcadores foi determinada através da citometria de fluxo e os dados clínicos foram obtidos através da revisão de prontuários. Dois grupos foram divididos quanto à expressão ou não dos referidos marcadores e comparados em relação às variáveis prognósticas. A média de idade na amostra foi de 6,28 anos, sendo o sexo masculino predominante (60,0%). A média de blastos contados na medula óssea (MO) e sangue periférico (SP) foram de 77,0 e 39,6, respectivamente. A morfologia L1 dos blastos da MO foi a mais frequente (80,0%). O perfil do hemograma, ao diagnóstico, indicou: 24.061 leucócitos/mm3, 56.510 plaquetas/mm3 e 8,0 g/dL de hemoglobina. De acordo com a classificação GBTLI-99, 60,0% dos pacientes se encontravam no grupo de baixo risco de recidiva e ao final da fase de indução do tratamento (D29), 70,0% dos pacientes alcançaram a remissão. Os pacientes portadores de LLA T apresentaram média de idade (10,6 anos; p= 0,0204) e leucometria (48.200/mm3; p= 0,0167) significativamente mais altas do que os pacientes com LLA B. 80,0% dos pacientes expressaram o marcador CD56 e nenhum paciente expressou o CD16 e/ou o CD57. Os pacientes que não expressaram o marcador CD56 tinham idade significativamente maior daqueles que o expressaram (9,3 anos; p= 0,0353). Para os pacientes portadores de LLA B, a média de blastos do SP dos pacientes que expressaram o marcador CD56 foi maior do que a média dos que não o expressaram (41,1; p= 0,0226). Conclui-se que a expressão do CD56 sugere um pior prognóstico para os pacientes com LLA B, em virtude de uma média significativamente maior de blastos contados no SP encontrada no nosso estudo, contudo, um maior número de casos e um maior tempo de observação seriam necessários para enfatizar melhor esta evidência.

Cancer is currently the leading cause of death by disease in children under the age of 15 in the US. While the number of childhood cancer survivors continues to grow, psychological research on this population has lagged. Existing research on the psychosocial effects of childhood cancer is marked by inconsistent conclusions as well as methodological limitations. However, the effect of childhood cancer on social functioning is one area with relatively more consistency. Existing research suggests that childhood cancer can lead to deficits in prosocial skills as well as the emergence of social problems. The present study investigated individual change in social functioning for five children diagnosed with Acute Lymphoblastic Leukemia ALL) over the first year of treatment compared to healthy control peers. Children with cancer demonstrated a decrease in social activity as well as an unexpected increase in social skills not demonstrated by healthy control children.

Diss. (sammanfattning) Uppsala : Univ., 2009. / Härtill 4 uppsatser.

T-ALL accounts for 15% of childhood leukemias and approximately 60% of patients overexpress TAL1. TAL1/SCL encodes a transcription factor that regulates hematopoiesis by dimerizing with additional transcription factors including E12, E47, and GATA-1. TAL1 has also been found to repress expression of NF-κB1, potentially promoting formation of an NF-κB p65/c-Rel heterodimer that encourages cell survival by up-regulating IAPs and IκB. However, the correlation between TAL1 and p65/c-Rel expression and their effects on downstream targets like IKK, IκB, and other anti-apoptotic proteins is poorly understood. Jurkat cells, expressing TAL1, were treated with TNFα and/or etoposide to induce apoptosis and experiments were performed to assess the expression of proteins of interest. Caspase-8 activity assays were also performed to help delineate the apoptotic signal present in these cells. Determining if interactions between TAL1, NF-κB, and other downstream targets help promote apoptotic resistance will further research into better, more targeted treatments for T-ALL. / Department of Biology

T-cell acute lymphoblastic leukemia (T-ALL) is a childhood cancer created through genetic alterations; most commonly upregulation of TALI and LMOI oncoproteins. T-ALL is treated with radiation and chemotherapy, but malignant T-cells are resistant to apoptotic stimulation. To study this disorder, AKR-DP-603 cells were transduced to express both oncoproteins. Western blots verified protein expression and each population was treated with etoposide. Caspase-3 and Annexin-V/FITC apoptosis assays were performed following treatment. When the response of control cells was compared to engineered cells, no difference was observed from the Annexin-V/FITC assay, and only LM01 cells showed a difference in the caspase-3 assay. Furthermore, cells were transfected with siRNA to TALI and LM01 and the apoptotic response was re-tested. Complete silencing was verified by Western and apoptotic activity varied in the TALI population for both assays. These differences might indicate that cells resisted etoposide induction and following silencing were sensitized apoptotic induction. / Department of Biology

Pediatric acute lymphoblastic leukemia (ALL) is the most common malignancy in children, which results from the malignant transformation of progenitor cells in the bone marrow into leukemic cells. The precise mechanisms for this transformation are not well defined, however recent studies suggest that aberrant regulation of gene expression or DNA methylation may play an important role. Hence, the aim of this thesis was to use novel methods to investigate genome-wide gene expression and DNA methylation patterns in a large collection of primary ALL cells from pediatric patients. With these studies, we aimed to increase the understanding of factors that regulate gene expression and DNA methylation in ALL. In the first study of the thesis we found that data obtained from genome-wide digital gene expression analysis enabled excellent cytogenetic subtype-specific classification of ALL cells and revealed new features of gene expression within the disease, such as prevalent antisense transcription and alternative polyadenylation. In the second study we used technology developed for large-scale single nucleotide polymorphism (SNP) genotyping for quantitative analysis of allele-specific gene expression (ASE), revealing widespread ASE in ALL cells. Analysis of DNA methylation in promoter regions of the genes displaying ASE using DNA-microarrays revealed frequent regulation of gene expression by DNA methylation. In the third study, using the same DNA methylation array, we identified differences in the DNA methylation patterns in ALL cells at diagnosis compared to healthy mononuclear cells from the bone marrow of the same children at remission. In the fourth study we measured the DNA methylation of >450,000 CpG sites across the genome in a large collection of ALL samples and non-leukemic control cells. We found that ALL cells displayed highly divergent DNA methylation patterns depending on their cytogenetic subtype and widespread regions of differential methylation were enriched for repressive histone marks. DNA methylation levels at distinct regions in the genome were substantially increased at relapse compared to matched cells from diagnosis. Collectively, the results presented in this thesis provide new insights into the patterns of gene expression and epigenetic changes in ALL and further increase our understanding of the development and progression of the disease, which will hopefully lead to better treatment options in the future.

[Truncated abstract] Acute lymphoblastic leukaemia (ALL) is the most common form of cancer that affects children and the leading cause of child cancer-related death. There have been dramatic improvements in the 5-year event free survival (EFS) for childhood ALL in recent years, with EFS reaching 75-90% for some forms of the disease. Despite this success, treatment for the disease is aggressive with numerous long and short-term side effects. Many cases of ALL are characterised by chromosomal defects including translocations, variations in chromosome number and the deletion of the tumour suppressor genes. Although these gross chromosomal changes have been extensively studied in childhood ALL, the cascade of altered gene expression that results from these changes has not. Further improvements in survival and the quality of life of survivors relies on a better understanding of the underlying biology of ALL. The primary aim of this study was to determine the gene expression profile of pre-B ALL specimens and normal, or non-malignant, control cells using microarrays in order to further examine the underlying biology of childhood ALL. ... Analysis of the ALL profile with two normal haematopoietic populations demonstrated that ALL specimens have a profile similar to that of CD34+ cells. Specifically, specimens of the MLL subtype had a profile that uniformly resembled that of CD34+ cells. Other subgroups contained specimens with profiles that ranged in similarity to that of CD34+ cells, however, the gene expression profile of all ALL specimens analysed more closely resembled the CD34+ cells than the more differentiated CD19+IgM- cells. This study identified exceptionally high expression of connective tissue growth factor (CTGF/CCN2) in ALL specimens compared to control cells. CTGF expression was v restricted to B-lineage ALL specimens, however, specimens containing the E2A-PBX1 translocation showed low or no expression. Protein studies by Western blot analysis demonstrated the presence of CTGF in ALL cell-conditioned media. The study presented here provides insight into the biology of ALL including the observation that ALL cells have an immature gene expression profile similar to that of CD34+ cells and the possible existence of an autocrine loop involving CTGF. The findings may also have clinical application in the future treatment of ALL, such as the use of metabolic inhibitors or the blocking of CTGF expression. This study provides an important insight into many aspects of ALL disease biology and may offer potential new therapeutic targets for the treatment of ALL.