Foram analisados 106 pacientes portadores de Linfoma de Hodgkin (LH) com recidiva da doença ou refratários ao tratamento inicial que foram submetidos ao transplante autólogo de células tronco hematopoiéticas (TCTH), na ordem consecutiva de sua realização, entre o mês de abril de 1993 a dezembro de 2007 em um único Centro Brasileiro: o Serviço de Transplante de Medula Óssea da FMUSP. O grupo teve a mediana etária de 28 anos, 55 pacientes (51,9%) eram do sexo masculino e houve predomínio da raça branca (87,6%). A mediana de seguimento clínico foi de 56,4 meses. Todos pacientes foram submetidos no pré TCTH a protocolos de tratamento convencionais, sendo que o uso dos protocolos MOPP, ABVD e sua associação foram utilizados em 97 pacientes (91,5%). Os pacientes foram classificados, de acordo com a resposta ao tratamento utilizado antes do TCTH, sendo 38,1% considerados refratários e 61,9% responsivos. Dos responsivos, 54 pacientes estavam em segunda remissão completa (85%). Tratamento com quimioterapia em alta dose pré TCTH foi feito em 45 (42,4%) dos pacientes (salvamento). A mobilização das células tronco hematopoiéticas foi realizada com ciclofosfamida 120 mg/kg dividida em dois dias seguido de fator estimulador de colônias de granulócitos (G-CSF) na dose de 6 a 17 mcg/kg em 83 (78%) pacientes. Em 25 pacientes (22%) houve falha de mobilização e a coleta foi realizada por múltiplas punções da medula óssea em centro cirúrgico. O valor mediano de células CD 34 coletadas foi de 2,6 x 106 células CD34/Kg de peso do paciente. Os condicionamentos mais utilizados foram BEAM e CVB, e não se encontrou diferença na sobrevida em relação ao regime empregado (p=0,17). A mediana de enxertia das células transplantadas foi de 12 dias. A sobrevida global após o TCTH pelo método de Kaplan-Meier foi, respectivamente, de 86% e 70% aos 5 e 10 anos. Não influenciaram a sobrevida na análise univariada o sexo, o estadio da doença e a presença de massa tumoral extensa. O principal fator preditivo de melhor sobrevida foi a presença de resposta a quimioterapia pré TCTH (p=0,0095) e hemoglobina maior que 10g/dL ao diagnóstico (p=0,0229). A mortalidade relacionada ao procedimento até o centésimo dia após o TCTH foi de 3,74%, e a principal causa de mortalidade tardia após TCTH foi a recidiva da doença / The study enrolled 106 patients with classic Hodgkin disease (HD) refractory or relapsed after initial treatment who underwent to autologous hematopoietic stem cell transplantation (HSCT) between April 1993 and December 2007. Median age was 28 years and 55 (51,9%) patients were male. Ninety three (87,6%) of patients were white. All patients underwent to conventional chemotherapy protocols prior HSCT. The use of MOPP, ABVD protocols and their associations were used in 97 (91,5%) of the patients. Disease classification was done according to the response to initial treatment and comprised 38,1% refractory and 61,9% responsive patients. In the group of responsive, 54 (85%) patients were in second complete remission. High dose chemotherapy prior HSCT was done as salvage in 45 (42,4%) patients. Stem cell mobilization was done after cyclophosphamide 120mg/kg divided in two days. Granulocyte-colony stimulating factor (G-CSF) 617 mcg/kg was given after cyclophosphamide in 83 (78%) patients. Twenty five (22%) patients failed the mobilization and stem cell harvest was done by bone marrow aspirations. The median number of CD34 collected was 2.6 x 106/L. Preparative regimen mostly used comprised BEAM and CVB and no differences was observed in overall survival (p=0.17). Median time to engraftment was 12 days. Median time of follow-up was 56.4 months. The overall survival (OS) was calculated by the Kaplan-Meier method and was 86% and 70% at 5 and 10 years, respectively. In the univariate analysis, response to initial treatment (p=0.009) and hemoglobin greater than 10g/dL at the time of diagnosis (p=0.02) were factors that influenced better OS. The gender, stage of disease and presence of bulky disease were not significant regarding OS in the univariate analysis. Treatment-related mortality (TRM) in 100-days was 3.74%. The major cause of late mortality was relapse of the disease

Finally, as the first step to study the regulation of Kit system, we found that IGF-I was a potent regulatory factor that up-regulated the expression of kitlga in zebrafish follicle cells. The stimulation involved transcription but not translation, indicating that the kitlga gene is a direct downstream target of IGF-I. The effect of IGF-I on kitlga was exerted via PI3K-Akt but not MAPK pathway. In contrast, the MAPK pathway may play a negative role in controlling kitlga expression. / Kit ligand (also named stem cell factor, SCF) is a pleiotropic growth factor with diverse biological functions. It exerts effects on target cells by binding to its cognate tyrosine kinase receptor, Kit. In mammals, accumulated evidence has demonstrated important roles for Kit ligand and Kit in gametogenesis, melanogenesis and haematopoiesis. However, very little is known about Kit system in other vertebrates. In the present study, we used zebrafish as the model to investigate the expression, regulation and function of the Kit system in the ovary. / On the other hand, cAMP is involved in regulating the expression of kitlga in zebrafish follicle cells. Two cAMP-activated effectors, PKA and Epac, have reverse effects. PKA promotes but Epac inhibits the expression of kitlga, which was identified by the respective activator. The effect of forskolin and H89 on IGF-I-induced expression of kitlga suggests a cross-talk between the two signaling pathways. Both hCG and PACAP inhibited IGF-I-induced kitlga expression, indicating that they may have negative regulation through cAMP signaling pathways in the full-grown follicles. (Abstract shortened by UMI.) / The zebrafish has two homologues of Kit ligand (kitlga and kitlgb) and Kit (kita and kitb ) instead of one copy for each as in mammals. The present study proposed the origin of these homologues in the zebrafish by phylogenetic and chromosome synteny analyses, and provided further evidence for neo- or subfunctionalization for both Kit ligands and Kit receptors in the zebrafish ovary. All four Kit system members exhibited distinct and significant changes in mRNA expression during folliculogenesis, particularly in the periovulatory period before and after final oocyte maturation and ovulation. / Then we further studied the spatial localization of each member within the follicle. The present study demonstrated that kitlga and kitb are exclusively expressed in the follicle layer, while kitlgb and kita only in the oocyte. Using CHO cell line as a bioreactor, we produced recombinant zebrafish Kitlga and Kitlgb. Analysis in mammalian COS-1 cells and zebrafish primary follicle cells confirmed their biological activity and binding specifity. Two opposite paracrine pathways of Kit system in the zebrafish ovary have been shown. Kitlga from the follicle cells preferably activates Kita in the oocyte in spite of the weak response of Kitb to it. Kitlgb from the oocyte, however, exclusively activates Kitb in the follicle cells without any effects on Kita. / Yao, Kai. / Adviser: Ge Wei. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 136-150). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

O objetivo deste estudo foi avaliar a evolução do estado nutricional, a ingestão alimentar por via oral (VO) e a utilização de terapias nutricionais complementares durante a internação de crianças e adolescentes submetidos ao transplante de células-tronco hematopoéticas (TCTH) alogênico em um hospital terciário. Estudo retrospectivo, com revisão de prontuários de pacientes submetidos ao TCTH, com idade entre 0 e 19 anos incompletos, entre janeiro de 2009 e dezembro de 2014. Foram coletados dados referentes a dados antropométricos, ingestão alimentar por VO, terapias nutricionais utilizadas (nutrição enteral (NE) e/ou parenteral (NP)); e sinais e sintomas clínicos em seis momentos: Internação, D0 (dia da infusão de células), D+7, D+14, D+21 e D+ 28. Foram avaliados 63 pacientes, 56% do sexo masculino, com uma mediana de idade de 10 anos. No momento da internação 100% dos pacientes tiveram suas necessidades energéticas atingidas pela VO, diminuindo a partir do D0 (cerca de 30%), com maior prevalência de utilização de NP e NE a partir do D+7. Inapetência, mucosite e náusea foram os sinais e sintomas mais frequentes. A partir do D+21 foi possível observar um aumento do aporte calórico por VO. Os pacientes apresentaram diminuição da ingestão alimentar ao longo da internação, porém, neste hospital, já se está conseguindo atingir um aporte calórico mais próximo do ideal, com auxílio de terapias nutricionais complementares. / The aim of this study was to describe the nutritional aspects relevant to the maintenance of a nutritional status during hospitalization of children and adolescents undergoing allogeneic hematopoietic stem cell transplantation (HSCT) at a tertiary hospital. A retrospective study with a review of medical records of patients undergoing HSCT, aged between 0 and 19 years of age (incomplete) between January 2009 and December 2014. Data were collected regarding food intake, nutritional therapies used, and clinical signs and symptoms in six times: Hospitalization, D0 (day of cell infusion), D+7, D+14, D+21 and D+28. Sixty-three patients were evaluated, being 56% males, with a median age of 10 years. At the time of hospitalization, 100% of patients had their energy needs met by mouth, decreasing from D0 (about 30%), with more prevalent use of PN (parenteral nutrition) and EN (enteral nutrition) from D+7. Loss of appetite, mucositis and nausea were the most frequent signs and symptoms. From D+21 it was possible to observe an increase in caloric intake by mouth. Patients showed decreased food intake throughout hospitalization, but in this hospital it has been already possible to get calorie intake closer to the ideal one with the help of complementary nutritional therapies.

Foram analisados 106 pacientes portadores de Linfoma de Hodgkin (LH) com recidiva da doença ou refratários ao tratamento inicial que foram submetidos ao transplante autólogo de células tronco hematopoiéticas (TCTH), na ordem consecutiva de sua realização, entre o mês de abril de 1993 a dezembro de 2007 em um único Centro Brasileiro: o Serviço de Transplante de Medula Óssea da FMUSP. O grupo teve a mediana etária de 28 anos, 55 pacientes (51,9%) eram do sexo masculino e houve predomínio da raça branca (87,6%). A mediana de seguimento clínico foi de 56,4 meses. Todos pacientes foram submetidos no pré TCTH a protocolos de tratamento convencionais, sendo que o uso dos protocolos MOPP, ABVD e sua associação foram utilizados em 97 pacientes (91,5%). Os pacientes foram classificados, de acordo com a resposta ao tratamento utilizado antes do TCTH, sendo 38,1% considerados refratários e 61,9% responsivos. Dos responsivos, 54 pacientes estavam em segunda remissão completa (85%). Tratamento com quimioterapia em alta dose pré TCTH foi feito em 45 (42,4%) dos pacientes (salvamento). A mobilização das células tronco hematopoiéticas foi realizada com ciclofosfamida 120 mg/kg dividida em dois dias seguido de fator estimulador de colônias de granulócitos (G-CSF) na dose de 6 a 17 mcg/kg em 83 (78%) pacientes. Em 25 pacientes (22%) houve falha de mobilização e a coleta foi realizada por múltiplas punções da medula óssea em centro cirúrgico. O valor mediano de células CD 34 coletadas foi de 2,6 x 106 células CD34/Kg de peso do paciente. Os condicionamentos mais utilizados foram BEAM e CVB, e não se encontrou diferença na sobrevida em relação ao regime empregado (p=0,17). A mediana de enxertia das células transplantadas foi de 12 dias. A sobrevida global após o TCTH pelo método de Kaplan-Meier foi, respectivamente, de 86% e 70% aos 5 e 10 anos. Não influenciaram a sobrevida na análise univariada o sexo, o estadio da doença e a presença de massa tumoral extensa. O principal fator preditivo de melhor sobrevida foi a presença de resposta a quimioterapia pré TCTH (p=0,0095) e hemoglobina maior que 10g/dL ao diagnóstico (p=0,0229). A mortalidade relacionada ao procedimento até o centésimo dia após o TCTH foi de 3,74%, e a principal causa de mortalidade tardia após TCTH foi a recidiva da doença / The study enrolled 106 patients with classic Hodgkin disease (HD) refractory or relapsed after initial treatment who underwent to autologous hematopoietic stem cell transplantation (HSCT) between April 1993 and December 2007. Median age was 28 years and 55 (51,9%) patients were male. Ninety three (87,6%) of patients were white. All patients underwent to conventional chemotherapy protocols prior HSCT. The use of MOPP, ABVD protocols and their associations were used in 97 (91,5%) of the patients. Disease classification was done according to the response to initial treatment and comprised 38,1% refractory and 61,9% responsive patients. In the group of responsive, 54 (85%) patients were in second complete remission. High dose chemotherapy prior HSCT was done as salvage in 45 (42,4%) patients. Stem cell mobilization was done after cyclophosphamide 120mg/kg divided in two days. Granulocyte-colony stimulating factor (G-CSF) 617 mcg/kg was given after cyclophosphamide in 83 (78%) patients. Twenty five (22%) patients failed the mobilization and stem cell harvest was done by bone marrow aspirations. The median number of CD34 collected was 2.6 x 106/L. Preparative regimen mostly used comprised BEAM and CVB and no differences was observed in overall survival (p=0.17). Median time to engraftment was 12 days. Median time of follow-up was 56.4 months. The overall survival (OS) was calculated by the Kaplan-Meier method and was 86% and 70% at 5 and 10 years, respectively. In the univariate analysis, response to initial treatment (p=0.009) and hemoglobin greater than 10g/dL at the time of diagnosis (p=0.02) were factors that influenced better OS. The gender, stage of disease and presence of bulky disease were not significant regarding OS in the univariate analysis. Treatment-related mortality (TRM) in 100-days was 3.74%. The major cause of late mortality was relapse of the disease

Linfomas pertencem a um grupo de neoplasias em que há proliferação monoclonal de linfócitos malignos, sendo uma das neoplasias mais frequentemente diagnosticadas em cães. Podem ser classificados quanto à forma anatômica em multicêntrico, mediastinal, digestório e extranodal. Dentre os extranodais, os linfomas cutâneos são classificados histologicamente como epiteliotrópicos e não epiteliotrópicos e são predominantemente de imunfenótipo T, com raros casos do tipo B. A principal característica histopatológica do linfoma epiteliotrópico em cães é o tropismo das células neoplásicas pela epiderme, mucosa ou estruturas anexas, enquanto o linfoma não epiteliotrópico é caracterizado pela infiltração dérmica e subcutânea sem invasão das estruturas anexas. Os linfomas cutâneos caninos têm progressão rápida, são considerados bastante agressivos e com mau prognóstico, com baixa taxa de resposta à quimioterapia. Um dos fatores que podem contribuir para isso é a resistência das células a múltiplas drogas e entre esses mecanismos de resistência estão o efluxo de drogas do meio intracelular para o extracelular por meio dos transportadores da família ABC, como a glicoproteína-P, MRP (multiple resistance protein) e BCRP (breast câncer resistance protein) e da LRP (lung resistance protein), uma proteína vault responsável pelo transporte nucleocitoplasmático. O objetivo deste estudo foi caracterizar imunofenotipicamente os linfomas cutâneos, a proliferação celular por meio do marcador Ki67, a expressão das proteínas de resistência glicoproteína-P, MRP, BCRP e LRP e avaliar a relação dessas proteínas com a sobrevida dos animais. Foi realizado um estudo retrospectivo com 21 casos de cães linfomas cutâneos com diagnóstico histopatológico. A técnica de imunoistoquímica foi utilizada para determinar a imunofenotipagem dos linfomas pelos marcadores CD3 e CD20, a proliferação celular por Ki67 e a expressão de glicoproteína-P, MRP, BCRP e LRP. Dos 21 animais, 38% tiveram diagnóstico histopatológico de linfoma epiteliotrópico, 52% eram linfomas não epiteliotrópicos, 5% dos casos de linfoma não tiveram epiteliotropismo definido e 5% foram classificados como neoplasia de células redondas. O imunofenótipo predominante foi CD3+CD20- (76%), 15% dos casos eram CD3-CD20+ e 9% eram CD3+CD20+. A mediana de células marcadas para Ki67 foi de 31%. Com relação aos marcadores de resistência a múltiplas drogas, a mediana da marcação de glicoproteína-P foi de 40%, a de LRP foi de 65% enquanto para MRP e BCRP, 19% e 23%, respectivamente. Os linfomas cutâneos não epiteliotrópicos foram mais frequentes que os epiteliotrópicos e o imunfenótipo predominante foi o T. A ocorrência de linfócitos CD3-CD20+ e CD3+CD20+ indica a necessidade de mais estudos e um painel mais amplo de anticorpos para subtipagem desses linfomas. A glicoproteína-P teve maior expressão nos linfomas não epiteliotrópicos do que nos epiteliotrópicos e não houve correlação entre as proteínas de resistência e o tempo de sobrevida dos animais, sugerindo que, além da biologia da neoplasia, outros mecanismos de resistência a múltiplas drogas diferente dos estudados possam ter um papel relevante na baixa resposta do linfoma cutâneo à quimioterapia. / Lymphoma is a group of blood cell tumors that develop from monoclonal proliferation of malignant lymphocytes. Lymphoma is the most frequent neoplasia in dogs and can be anatomically classified in multicentric, mediastinal, digestive and extranodal. Cutaneous lymphomas an extranodal type of lymphoma are classified histologically in epitheliotropic and non-epitheliotropic and are predominantly of T-cell immunophenotype, and rare cases of B cell phenotype. The main histopathological characteristic of epitheliotropic lymphoma in dogs is the tropism of neoplastic cells by the epidermis, mucosa or adjacent structures, while non-epitheliotropic lymphoma is characterized by dermal and subcutaneous infiltration without invasion of adjacent structures. Canine cutaneous lymphomas have rapid progression, are considered very aggressive and have poor prognosis. These dogs, usually have a low rate of response to chemotherapy which can be associated to an antineoplastic resistance. Among mechanisms of resistance are efflux of drugs from intracellular to extracellular through ABC family transporters such as P-glycoprotein, MRP (multple resistance protein) and BCRP (breast cancer resistance protein) and LRP (lung resistance protein), a vault protein responsible for nucleocytoplasmic transport. The aim of this study was to characterize immunophenotypically cutaneous lymphomas, measure cell proliferation using the Ki67 marker, the expression of resistance proteins P-glycoprotein, MRP, BCRP and LRP and to evaluate the relationship of these proteins with the survival of the animals. A retrospective study was performed with 21 cases of dogs with cutaneous lymphoma with histopathological diagnosis. Immunohistochemical was used to immunophenotyping of lymphomas by CD3 and CD20 markers, Ki67 cell proliferation, and P-glycoprotein, MRP, BCRP and LRP expression. Of the 21 animals, 38% had histopathological diagnosis of epitheliotropic lymphoma, 52% were non-epitheliotropic lymphomas, 5% of lymphoma cases had no definition and 5% were classified as round cell neoplasia. The predominant immunophenotype was CD3+CD20- (76%), 15% of the cases were CD3-CD20 + and 9% were CD3 + CD20 +. The median of cells labeled for Ki67 was 31%. Regarding the markers of resistance to multiple drugs, the median of the P-glycoprotein label was 40%, which 65% of LRP while for MRP and BCRP, 19% and 23%, respectively. Non-epitheliotropic cutaneous lymphomas were more frequent than epitheliotropic lymphomas and the predominant immunophenotype was T. The occurrence of CD3-CD20+ and CD3+CD20+ lymphocytes indicates the need for further studies and a wider panel of antibodies for subtyping these lymphomas. P-glycoprotein had higher expression in non-epitheliotropic lymphomas than in epitheliotropic lymphomas and there was no correlation between resistance proteins and survival time of the animals, suggesting that in addition to the biology of neoplasia other mechanisms of resistance to multiple drugs different from those studied may play a relevant role in the low response of cutaneous lymphoma to chemotherapy.

Les cellules souches hématopoïétiques (CSH) sont à l’origine de l’ensemble des cellules hématopoïétiques, mais les mécanismes responsables de leurs réponses au stress ne sont que partiellement compris. J’ai étudié le rôle du facteur de transcription Helios dans les CSH, dans lesquelles il est fortement exprimé. J’ai trouvé que les CSH de souris nulles pour Helios (He-/-) possèdent un plus fort potentiel de reconstitution que les CSH WT dans des expériences de transplantations en série. De manière frappante, les souris âgées de 2 ans possèdent 8 fois plus de CSH fonctionnelles par rapport aux souris vieilles WT. De plus, le pool de CSH de long terme de souris He-/- vieilles ressemblent aux CSH WT jeunes en termes de phénotype et de fréquences. Les CSH He-/- vieilles présentent une dérégulation de gènes impliqués dans le vieillissement. De plus,les CSH He-/- jeunes sous-expriment des gènes codant des protéines impliquées dans la réparationde l’ADN ainsi que dans la voie p53. Quand les CSH He-/- et WT sont traitées avec différents agents radiomimétiques qui induisent des cassures simple et double brins à l’ADN, tels que la néocarzinostatine, la camptothécine ou l’étoposide, l’entrée en apoptose, en sénescence et l’arrêt de la prolifération des CSH He-/- sont altérées. Ce phénotype est accompagné d’une faible induction des gènes cibles de p53 et d’une altération du dégagement des foyers gammaH2AX. De plus, j’ai montré que Helios agit en synergie avec p53 pour réguler les réponses aux dommages à l’ADN des CSH. Mes résultats suggèrent qu’en synergie avec p53, Helios contrôle le vieillissement des CSH en prévenant l’accumulation des dommages de l’ADN des CSH. / Hematopoietic stem cells (HSCs) give rise to all blood cell lineages but the mechanisms responsible of HSCs responses to stress remain partially understood. I studied the role of the transcription factor Helios in HSCs, where Helios is highly and specifically expressed. I found that HSCs from young Helios null mice (He-/-) reconstitute the hematopoietic system of irradiated recipient mice similarly to HSCs from WT mice in primary transplantations, but out-perform WT cells in secondary and tertiary transplantations. Strikingly, HSCs from 2-year-old He-/- mice had 8-fold higher reconstitution potential than old WT HSCs in primary transplantations. Moreover, the pool of long-term HSCs in old He-/- mice resembles that of young WT animals in both phenotype and frequency. HSCs from old He-/- mice present a down regulation of genes involved in aging. Further, young He-/- HSCs express reduced mRNA levels of genes encoding DNA repair proteins as well as those associated with thep53 pathway. When He-/- and WT HSCs were subjected to DNA damage by different agents like neocarzinostatin, camptothecin, or etoposide, DNA damage-induced apoptosis, senescence and cell cycle arrest were significantly impaired in He-/- HSCs. This phenotype was accompanied by a poor induction of p53 target genes and impaired clearance of gammaH2AX foci. Furthermore, I found that Helios synergies with p53 to regulate the DNA damage responses of HSCs. My results suggest that,in synergy with p53, Helios controls HSC aging by preventing the accumulation of DNA damage in these cells.

O bussulfano (BU) e a ciclofosfamida (CY) são fármacos utilizados nos regimes de condicionamento pré-transplante de células tronco hematopoéticas (TCTH). O BU apresenta estreito intervalo terapêutico, alta variabilidade interindividual na farmacocinética e graves reações adversas. O presente estudo avaliou a administração de uma dose teste de BU oral para a individualização do regime de dosagem, definiu o melhor tempo de coletas esparsas para o monitoramento terapêutico do BU e validou um algoritmo baseado em modelo compartimental e farmacocinética populacional em pacientes submetidos ao TCTH. Trinta pacientes portadores de doenças hematológicas tiveram o tratamento com BU individualizado baseado em uma dose teste oral de 0,25 mg/Kg de BU. As doses foram baseadas no clearance aparente calculado na dose teste e as concentrações plasmáticas foram confirmadas após a quinta dose de tratamento. Os coeficientes de variação obtidos entre os valores de clearance avaliados na dose teste e na quinta dose foram <= 30%, exceto para 5 pacientes. Não foram observadas associação entre os parâmetros farmacocinéticos do BU e a evolução clínica dos pacientes. Com a finalidade de estimar os melhores tempos de coletas ideais para aplicação no monitoramento terapêutico do BU, um modelo farmacocinética populacional foi utilizado e um esquema de coletas esparsas com não mais de cinco amostras por paciente (t = 0,5; 2,25; 3; 4 e 5 horas após a dose) demonstrou ser suficiente para a caracterização da farmacocinética do BU. O presente estudo avaliou também a farmacocinética dos enantiômeros da ciclofosfamida (CY) e seus metabólitos (4-hidroxiciclofosfamida e carboxiciclofosfamida), em pacientes submetidos ao TCTH. Foram investigados pacientes portadores de esclerose sistêmica (n=10) e esclerose múltipla (n=10) em regime de condicionamento com 50 mg CY /kg/dia durante 4 dias. Dois ensaios específicos baseados na análise por LC-MS/MS foram desenvolvidos e validados para analisar os enantiômeros da CY e seus metabólito 4- hidroxiciclofosfamida (HCY) e carboxiciclofosfamida (CEPM) em plasma humano. Os parâmetros farmacocinéticos dos enantiômeros da CY e seus metabólitos foram calculados empregando o programa WinNonlin e mostraram acúmulo plasmático dos enantiômeros (S)- (-)-CY (AUC 215, 0 vs 186,2 ?g.h/mL para os paciente EM e 219,1 vs 179,2 ?g.h/mL para os paciente ES) e HCY (1), provavelmente o (R)-(+)-HCY (AUC 5,6 vs 3,7 ?g.h/mL para os paciente EM e 6,3 vs 5,6 ?g.h/mL para os paciente ES) em ambos os grupos de pacientes investigados. A disposição cinética do metabólito CEPM não mostrou enantiosseletividade. A farmacocinética da CY e seus metabólitos HCY e CEPM não diferiu entre os pacientes portadores de EM ou ES. Não foi observado correlação entre o metabolismo da CY e os genótipos avaliados (CYP2B6 e CYP2C9). Não foi possível correlacionar os valores de AUC0-? dos enantiômeros da CY e/ou dos metabólitos HCY e CEPM com a toxicidade ao uso de CY em virtude do pequeno número de pacientes investigados. / Busulfan (BU) and cyclophosphamide (CY) are drugs used during conditioning treatment for hematopoietic stem cell transplantation (HSCT). BU presents narrow therapeutic window, high interindividual variability in the pharmacokinetics and serious adverse effects. The present study evaluated the administration of a BU test dose for dose individualization, set the best sparse sampling scheme for BU therapeutic monitoring and validated an algorithm based on compartmental and population pharmacokinetics model in HSCT patients. Thirty patients received BU individualized treatment based on an oral test dose of 0.25 mg/kg. Doses were based on apparent clearance calculated with BU test dose. Plasma concentrations were confirmed after the fifth treatment dose. Coefficients of variation obtained between the clearance values evaluated in the test dose and fifth dose were <= 30%, except for 5 patients. No association between BU pharmacokinetic parameters and clinical outcome was observed. To estimate the ideal sampling scheme for BU therapeutic drug monitoring, a population pharmacokinetic model was used. Sparse sampling scheme with no more than five samples per patient (t = 0.5, 2.25, 3, 4 and 5 hours after dosing) was shown to be sufficient to characterize the BU pharmacokinetics. This study also evaluated the pharmacokinetics of the cyclophosphamide enantiomers and its metabolites (4-hydroxycyclophosphamide and carboxicyclophosphamide) in HSCT patients. We investigated patients with systemic sclerosis (SS) (n = 10) and multiple sclerosis (MS) (n = 10) in the conditioning regimen with CY 50 mg/kg/day for 4 days. Two specific tests based on LC-MS/MS analysis were developed and validated to analyze the CY enantiomers and its metabolite 4-hydroxycyclophosphamide (HCY) and carboxicyclophosphamide (CEPM) in human plasma. Pharmacokinetics of CY enantiomers and its metabolites were calculated using WinNonlin software and showed plasma accumulation of (S)-(-)-CY (AUC 215.0 vs 186.2 ?g.h/mL for the MS patient and 219.1 vs. 179.2 ?g.h/mL for the SS patient) and HCY (1), probably the (R)-(+)-HCY (AUC 5.6 vs 3.7 ?g.h /mL for MS patients and 6.3 vs 5.6 ?g.h/ mL for the SS patients) enantiomers in both groups of investigated patients. CEPM kinetics disposition showed lack of enantioselectivity. The pharmacokinetics of CY and its metabolites (HCY and CEPM) did not differ between patients with MS or SS. There was no correlation between the metabolism of CY, CYP2B6 and CYP2C9 genotypes. It was not possible to correlate the AUC0-? of CY enantiomers and/or its metabolites (HCY and CEPM) with CY toxicity due to the small number of patients investigated.

Hematopoietic stem cell (HSC) development is accompanied by dynamic changes in the transcriptional program. How the corresponding transcriptional programs are related to the epigenetic mechanism is poorly understood. To fill this gap, we first profiled the transcriptomes and epigenomes using RNA-Seq and ChIP-Seq for five key developmental stages of HSC emergence in the mouse embryo. Using epigenetic markers, we identified novel 12,000~17,000 enhancers for each developmental stage. We applied a computational tool to link those enhancers to their target genes. Systematical analysis of enhancer-promoter (EP) pairs using network-based strategy reveals multiple novel key transcription factors for early specification of HSC in the mouse embryo. Second, we compared the 3D genome organization, epigenomes, and transcriptome of fetal and adult HSCs in the mouse. We found that higher-order genome structures are largely conserved between fetal and adult HSCs, including chromosomal compartments and topologically associating domains (TADs). However, chromatin interactions within TADs exhibit substantial differences. We found that promoters within 23% (242/1039) of TADs undergo interaction changes. Transcription factor motif analysis of HSC-specific enhancer-promoter loops suggests a role of KLF1 in mediating condition-specific enhancer looping and regulation of genes involved in cell cycle. Our result provides a comprehensive view of the differences in 3D genome organization, epigenome, and transcriptome between fetal and adult HSCs.

Despite the relatively large number of parents with cancer, relatively little is known about the extent to which having cancer affects the parenting experience. Qualitative studies have identified issues and concerns that create distress among parents with cancer, but quantitative studies have yet to be conducted. Studies demonstrate that parents with cancer experience psychological distress, and that parenting self-efficacy is related to psychological distress among parents without cancer. However, no study to date has examined the relationships between parenting self-efficacy and psychological distress among parents with cancer. This study sought to address these gaps in the literature by comparing parents with cancer to parents without cancer on measures of parenting self-efficacy and psychological distress. It was hypothesized that cancer patients would report lower parenting self-efficacy and higher levels of psychological distress than parents without cancer. This study also sought to explore whether parenting or general self-efficacy mediated the relationship between cancer status and psychological distress. A sample of 57 patients who had been diagnosed with cancer and undergone hematopoietic stem cell transplantation (HSCT), and a control group of 57 parents with no history of cancer were recruited for participation in the study. Patients were recruited during routine outpatient visits or by mail, and controls were recruited using community outreach. Medical record reviews were conducted to assess clinical variables, and participants filled out a standard demographic questionnaire as well as self-report measures of parenting self-efficacy, general self-efficacy, and psychological distress. As hypothesized, results demonstrated that parents with cancer reported less parenting self-efficacy, and more psychological distress than controls (all p-values < .05). Furthermore, findings indicated that both parenting self-efficacy and general self-efficacy mediated the relationship between cancer status and psychological distress. This study fills several gaps in the quantitative literature on parenting with cancer, and suggests that both parenting and general self-efficacy are possible targets for interventions seeking to lessen distress among parents with cancer. Future research should use matched case-control designs to examine longitudinal relationships between parenting self-efficacy and psychological distress, and empirically evaluate interventions aimed at improving parenting and general self-efficacy.

Hematopoietic stem cells (HSCs) that function to maintain the hematopoietic compartment through self-renewal and differentiation capacities, as well as their downstream progeny, are susceptible to transformation resulting in the generation of the leukemic stem cell (LSC). Chief in the factors that control HSC regulation and protection of the HSC compartment is the cellular redox environment. Deregulation of the Hematopoietic Stem/Progenitor Cell (HSPC) redox environment results in loss of HSPC function and exhaustion. The characteristic developments of HSPC exhaustion via exposure to redox stress closely mirror phenotypic traits of hematopoietic malignancies, presenting the HSPC/LSC redox environment as a potential therapeutic target. While myelosuppression and HSPC exhaustion are detrimental side effects of classical chemotherapies, new approaches that differentially modify the HSPC/LSC redox environment may demonstrate LSC cytotoxicity while offering protection of normal HSPC function via differential activation of internal signaling pathways. Precisely how the redox environment and downstream signaling events are affected by these treatments remains unclear; thus highlighting the need for robust methods that evaluate the HSPC/LSC redox state. Because the glutathione (GSH), glutathione disulfide (GSSG) redox couple heavily contributes to the management of HSPC function and redox environment, characterizing the GSH/GSSG redox potential at the HSPC level would provide great insight for therapeutic opportunities. However, accurate measurement the GSH/GSSG redox potential within HSPCs/LSCs has been difficult due to their inherently low numbers. Here, we describe the development and validation of a sensitive method used for the direct and simultaneous quantitation of both oxidized and reduced GSH via LC-MS/MS. We use these methodologies to establish a difference in GSH-GSSG half-cell reduction potentials between normal and malignant HSPCs and examine the therapeutic effect of a redox active MnSOD mimetic, Mn(III) mesotetrakis (N-n-butoxyethylpyridinium-2yl) porphyrin, MnTnBuOE-2-PyP5+ (MnP), within these populations in vitro as well as within a human xenograft model in vivo. MnP demonstrates significant cytotoxic effects in several malignant models, while inducing an opposite cytoprotective effect in normal HSPC populations. The GSH/GSSG redox balance, specifically managed by glutathione reductase activity, is identified as a determining factor of MnP efficacy in various malignant populations. Treatment of the human myelodysplastic cell line (MDSL) offers mechanistic insights into MnP efficacy through hydrogen peroxide mediated activation of activator protein 1 (AP-1) signaling. We identify the redox dependent activation of JunB, a known regulator of normal myeloid lineage HSC proliferation, as a transcriptional mechanistic mediator of MnP treatment induced AP-1 signaling resulting in malignant cytotoxicity. The development of this novel method allowing for the identification of targetable differences between normal and malignant cell populations has provided insight to the underpinnings of potential redox based therapies. Additionally, the finding that MnP can target varying cellular redox states and exert selective cytotoxicity in malignant over normal populations by re-gaining lost control of AP-1 signaling demonstrates the potential for development of safe therapeutics within a variety of clinical applications.