L'objectif de notre travail est de mieux comprendre le rôle de LMP1 et de ses variants délétés de 30 ou 69pb en C-terminal dans le développement du lymphome de Hodgkin (LH) chez les patients VIH+. Le séquençage de LMP1 dans des échantillons de sang total et de cellules oropharyngées de patients de la cohorte Lymphovir (LH/VIH+) et de deux populations contrôles (VIH+ et LH) a permis d'étudier la fréquence des variants de LMP1 in vivo. Ce travail a révélé que le variant LMP1-del30 semble plus fréquent chez les patients avec une immunosuppression modérée, durant laquelle l'incidence des LH est élevée. Par ailleurs, nous avons établi un modèle cellulaire dérivé de LH, exprimant LMP1 de façon inductible, montrant des différences d'expression des cytokines et de progression du cycle cellulaire en fonction des variants de LMP1. Notre travail supporte l'hypothèse d'une plus grande oncogénicité du variant LMP1-del30 et suggère qu'il pourrait être un facteur de risque de développer un LH. / The aim of this work was to improve our understanding of the role of LMP1 and its 30bp and 69bp deletion variants in the development of Hodgkin's lymphoma (HL) among HIV+ people. Blood and saliva samples were collected from HL/HIV+ patients recruited in the Lymphovir cohort, as well as in two control populations (HIV+ and HL). Next-Generation Sequencing allowed us to determine the frequency of LMP1 variants in these samples. This work showed that the del30-LMP1 variant seems to be more frequent in patients with a moderate immunosuppression, associated with a higher HL incidence. Besides, we established three HL-derived cell lines expressing WT-LMP1 or its variants and showed differences of cytokine expression and progression of the cell cycle depending on the variant. Our work supports the hypothesis of a greater oncogenicity of del30-LMP1 variant and suggests that it could be a risk factor for the development of HL.

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 155-182).

Thesis (doctoral)--Katholieke Universiteit te Nijmegen.

Orientador: Maria Aparecida Custódio Domingues / Banca: Flávio de Oliveira Lima / Banca: Gabriela Gualco / Resumo: O Linfoma de Hodgkin (LH) é uma neoplasia hematopoiética que acomete caracteristicamente adultos jovens e apresenta, quando não tratado, curso clínico fatal. O diagnóstico precoce e preciso desse linfoma, associado à terapia moderna, por outro lado, tem proporcionado diminuição dramática das taxas de letalidade. Ainda assim, cerca de 15-20% dos pacientes evoluem de maneira insatisfatória com resistência a terapia primária ou recaída precoce pós-tratamento. Nesse sentido, há estudos variados na tentativa de buscar perfis prognósticos capazes de selecionar pacientes candidatos a terapias particulares. O IMP3 (insulin-like growth factor mRNA binding protein 3) tem sido descrito como biomarcador relacionado a pior prognóstico em diversas neoplasias, especialmente carcinomas, mas ainda pouco estudado em neoplasias hematopoiéticas. Para avaliar seu potencial papel prognóstico no LH, foi estudada a expressão do IMP3 em 61 casos, incluindo estratificação da imunocoloração em intensidades (0, 1+, 2+ e 3+) e relação com sobrevida, dados clínicos, aspectos morfológicos e imuno-histoquímicos. A expressão forte (intensidade 3+) para IMP3 foi observada em 61% (34/56) dos LH e apresentou forte indicio de associação com melhor sobrevida livre de doença. Nossos achados mostram o IMP3 como potencial biomarcador de melhor prognóstico em LH / Abstract: Hodgkin lymphoma (HL) is a hematopoietic neoplasm that characteristically affects young adults and, if untreated, presents a fatal clinical course. Early and accurate diagnosis of this lymphoma associated with modern therapeutic management, on the other hand, has promoted a dramatic decrease in mortality rates. Despite this, around 15-20% of patients show unsatisfactory progression, with resistance to primary therapy or early relapse following treatment. The literature comprises numerous studies attempting to determine prognostic profiles that are capable of selecting candidate patients for specific therapies. Insulin-like growth factor mRNA binding protein 3 (IMP3) has been described as a biomarker that indicates worse prognosis in several malignancies, particularly carcinomas; however, studies of IMP3 in hematopoietic malignancies are rare. To assess their potential prognostic role in HL, IMP3 expression was studied in 61 cases and included stratification of immunostaining intensities (0, +, ++ and +++) and their relation to status of life, clinical data and morphological and immunohistochemical features. Intense IMP3 expression (+++) was observed in 61% (34/56) cases and showed a strong indication of association with better disease-free survival. Our findings show that IMP3 is a potential biomarker of better prognosis in HL / Mestre

Le traitement du lymphome B non hodgkinien (NHL) est généralement basé sur la combinaison d’un anticorps monoclonal anti-CD20, le rituximab, et de la chimiothérapie. Cependant, de nombreux patients deviennent réfractaires au ciblage du récepteur CD20. Dans cette thèse, l’effet d’un nouvel anticorps monoclonal anti-CD37 conjugué au Luthétium-177 (177Lu-lilotomab, Betalutin®) est étudié dans des modèles précliniques de lymphome non hodgkinien et comparé au rituximab radiomarqué au luthétium-177 (177Lu-rituximab). Nous avons développé une approche radiobiologique qui distingue les effets cytotoxiques dus à l’anticorps monoclonal et dus aux rayonnements ionisants dans des lignées cellulaires de lymphome humain. Cette méthode a permis de montrer qu’in vitro, le rituximab et le 177Lu-rituximab étaient plus cytotoxiques que le lilotomab et le 177Lu-lilotomab dans la lignée cellulaire radiorésistante Ramos (modèle du lymphome de Burkitt). Inversement, le 177Lu-lilotomab et le 177Lu-rituximab ont montré la même cytotoxicité dans la lignée cellulaire radiosensible DOHH2 (modèle de lymphome folliculaire transformé). Leur cytotoxicité était plus faible dans la lignée cellulaire Rec-1 (modèle du lymphome du manteau) que dans les cellules DOHH2. Ces résultats ont été confirmés in vivo sur des souris traitées par injection intraveineuse après xénogreffe sous-cutanée de cellules Ramos ou DOHH2. Le 177Lu-lilotomab et le 177Lu-rituximab ont montré la même efficacité thérapeutique chez les souris xénogreffées avec les cellules radiosensibles DOHH2, alors que le lilotomab non radiomarqué était moins efficace que le rituximab. Inversement, chez les souris xénogreffées avec les cellules radiorésistantes Ramos, la plus faible efficacité du 177Lu-lilotomab comparé au 177Lu-rituximab peut seulement être compensée par une augmentation de dose absorbée à la tumeur par le 177Lu-lilotomab. Mécanistiquement, la réponse cellulaire des tumeurs aux radiations dépend de la réponse apoptotique des cellules et de la réduction de l’arrêt en G2/M du cycle cellulaire via les phosphorylations médiées par WEE-1 et MYT-1 de la kinase dépendante des cyclines-1 (CDK1) sur la tyrosine 15 et thréonine 14. Ces résultats indiquent que l’interaction synergistique entre les effets cytotoxiciques du 177Lu et du lilotomab dans les tumeurs montrant une réduction des niveaux de phosphorylations de CDK1 peut compenser le manque d’efficacité thérapeutique du lilotomab comparé au rituximab. / Currently, B-cell Non-Hodgkin Lymphoma (NHL) treatment relies on the anti-CD20 antibody rituximab and chemotherapy. However, some patients become refractory to this therapy. Here, the effect of the novel anti-CD37 antibody-radionuclide conjugate 177Lu-lilotomab (Betalutin®) was investigated in NHL preclinical models and compared to 177Lu-labeled rituximab (anti-CD20 antibody). We developed a radiobiological approach that discriminates between the cytotoxic effects of unlabeled antibodies and of radiation in human lymphoma cell lines. This method allowed showing that in vitro, rituximab and 177Lu-rituximab were more cytotoxic than lilotomab and 177Lu-lilotomab in the radioresistant Ramos Burkitt’s lymphoma cell line. Conversely, 177Lu-rituximab and 177Lu-lilotomab had similar efficacy in the radiosensitive follicular lymphoma DOHH2 cell line. Their cytotoxicity was lower in mantle cell lymphoma Rec-1 cells that are less radiosensitive than DOHH2 cells. These results were confirmed in vivo in mice treated by intravenous injection of these antibodies after subcutaneous xenografts of Ramos or DOHH2 cells. 177Lu-lilotomab and 177Lu-rituximab showed the same therapeutic efficacy in mice xenografted with radiosensitive DOHH2 cells, although unlabeled lilotomab was less efficient than rituximab. Conversely, in mice xenografted with radioresistant Ramos cells, the lower efficacy of 177Lu-lilotomab compared with 177Lu-rituximab could only be compensated by increasing 177Lu-lilotomab tumor absorbed dose. Mechanistically, the tumor cell response to radiation depended on the cell apoptotic response and reduction of G2/M cell cycle arrest through WEE-1 and MYT1-mediated phosphorylation of cyclin-dependent kinase-1 (CDK1) at tyrosine 15 and threonine 14. These results indicate that the synergistic interaction between 177Lu irradiation and lilotomab cytotoxic effects in tumors with reduced CDK1 phosphorylation levels can correct the lower therapeutic efficacy of lilotomab compared with rituximab.

Made available in DSpace on 2015-12-10T14:23:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-19. Added 1 bitstream(s) on 2015-12-10T14:29:27Z : No. of bitstreams: 1 000849806.pdf: 849500 bytes, checksum: fbe135630fc95ef07e7c2a3ad5436dca (MD5) / O Linfoma de Hodgkin (LH) é uma neoplasia hematopoiética que acomete caracteristicamente adultos jovens e apresenta, quando não tratado, curso clínico fatal. O diagnóstico precoce e preciso desse linfoma, associado à terapia moderna, por outro lado, tem proporcionado diminuição dramática das taxas de letalidade. Ainda assim, cerca de 15-20% dos pacientes evoluem de maneira insatisfatória com resistência a terapia primária ou recaída precoce pós-tratamento. Nesse sentido, há estudos variados na tentativa de buscar perfis prognósticos capazes de selecionar pacientes candidatos a terapias particulares. O IMP3 (insulin-like growth factor mRNA binding protein 3) tem sido descrito como biomarcador relacionado a pior prognóstico em diversas neoplasias, especialmente carcinomas, mas ainda pouco estudado em neoplasias hematopoiéticas. Para avaliar seu potencial papel prognóstico no LH, foi estudada a expressão do IMP3 em 61 casos, incluindo estratificação da imunocoloração em intensidades (0, 1+, 2+ e 3+) e relação com sobrevida, dados clínicos, aspectos morfológicos e imuno-histoquímicos. A expressão forte (intensidade 3+) para IMP3 foi observada em 61% (34/56) dos LH e apresentou forte indicio de associação com melhor sobrevida livre de doença. Nossos achados mostram o IMP3 como potencial biomarcador de melhor prognóstico em LH / Hodgkin lymphoma (HL) is a hematopoietic neoplasm that characteristically affects young adults and, if untreated, presents a fatal clinical course. Early and accurate diagnosis of this lymphoma associated with modern therapeutic management, on the other hand, has promoted a dramatic decrease in mortality rates. Despite this, around 15-20% of patients show unsatisfactory progression, with resistance to primary therapy or early relapse following treatment. The literature comprises numerous studies attempting to determine prognostic profiles that are capable of selecting candidate patients for specific therapies. Insulin-like growth factor mRNA binding protein 3 (IMP3) has been described as a biomarker that indicates worse prognosis in several malignancies, particularly carcinomas; however, studies of IMP3 in hematopoietic malignancies are rare. To assess their potential prognostic role in HL, IMP3 expression was studied in 61 cases and included stratification of immunostaining intensities (0, +, ++ and +++) and their relation to status of life, clinical data and morphological and immunohistochemical features. Intense IMP3 expression (+++) was observed in 61% (34/56) cases and showed a strong indication of association with better disease-free survival. Our findings show that IMP3 is a potential biomarker of better prognosis in HL

Made available in DSpace on 2016-06-07T17:12:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-23. Added 1 bitstream(s) on 2016-06-07T17:16:37Z : No. of bitstreams: 1 000866315.pdf: 2093030 bytes, checksum: ce1db846f21a0409224ee2b9a2b57f4a (MD5) / Fundamento: a cardiotoxicidade tardia em sobreviventes de linfoma não Hodgkin (LNH) tratados com antraciclina manifesta-se por insuficiência cardíaca (IC), definida pela redução da fração de ejeção do ventrículo esquerdo (FEVE). Estes pacientes podem apresentar tardiamente sinais sugestivos de cardiotoxicidade, ainda que não manifestem clínica de IC ou redução da FEVE. O estudo da função cardiovascular por meio da utilização de métodos diagnósticos mais sensíveis para a detecção de disfunção miocárdica precoce poderia contribuir com a prevenção e tratamento da cardiotoxicidade. Objetivos: avaliar sinais de cardiotoxicidade subclínica tardia em pacientes com diagnóstico prévio de LNH tratados com antraciclina por meio de exame clínico e laboratorial com biomarcadores cardíacos, ecocardiografia transtorácica bidimensional com speckle tracking, ultrassonografia de carótidas e teste ergométrico; relacionar os índices de função miocárdica derivados da ecocardiografia com speckle tracking com a capacidade de exercício estimada pelo teste ergométrico. Metodologia: ensaio clínico controlado não randomizado, 1:2, que incluiu sobreviventes de LNH tratados com antraciclina há mais de 1 ano, sem diagnóstico prévio de IC (grupo antraciclina) e indivíduos saudáveis (grupo controle), pareados por sexo e idade. Para todos os participantes do estudo foram avaliados: sinais e sintomas clínicos de IC, fatores de risco e escore de risco cardiovascular, uso de medicações, exames bioquímicos sanguíneos, teste com esteira ergométrica, ultrassonografia de carótidas para obtenção da espessura íntima média das carótidas comuns e ecocardiograma transtorácico com medidas tradicionais, entre elas a FEVE pelo método de Simpson, além da determinação de strain global longitudinal bidimensional (SGL) por speckle tracking. Resultados: o grupo antraciclina foi constituído por 28 indivíduos com idade média... / Background: late cardiotoxicity in non-Hodgkin lymphoma survivors (NHL) treated with anthracycline is manifested by heart failure (HF), defined by reduced left ventricular ejection fraction (LVEF). These patients may show signs suggestive of late cardiotoxicity, although not express clinic HF or reduced LVEF. The study of the cardiovascular function through the use of more sensitive diagnostic methods for the early detection of myocardial dysfunction may contribute to the prevention and treatment of cardiotoxicity. Objectives: to evaluate late subclinical cardiotoxicity signals in patients previously diagnosed with NHL treated with anthracycline through clinical and laboratory examination with cardiac biomarkers, two-dimensional transthoracic speckle tracking echocardiography, carotid ultrasound and treadmill test; to relate the derived myocardial function indexes of speckle tracking echocardiography with exercise capacity estimated by treadmill test. Methodology: non-randomized controlled trial, 1: 2, which included NHL survivors treated with anthracycline for more than one year, no previous diagnosis of HF (anthracycline group) and healthy subjects (control group), matched for sex and age. For all study participants were evaluated: clinical signs and symptoms of HF, risk factors and cardiovascular risk score, use of medications, blood biochemical tests, test with treadmill, carotid ultrasound to obtain intima-media thickness of the common carotid and transthoracic echocardiography with traditional measures including LVEF using the Simpson method, and the determination of two-dimensional global longitudinal strain (GLS) by speckle tracking. Results: the anthracycline group consisted of 28 subjects with a mean age of 52 (44; 65) years, 64% male, with a cumulative total dose of 386 (200; 400) mg/m2 of doxorubicin, and 63 subjects in the control group. The groups did not differ with respect to clinical examination, risk factors, ...

Orientador: Meliza Goi Roscani / Coorientador: Beatriz Bojikian Matsubara / Banca: João Carlos Heub / Banca: Katachi Okoshi / Banca: Sérgio Luiz Brasileiro Lopes / Banca: Isabeth da Fonseca Estevão / Resumo: Fundamento: a cardiotoxicidade tardia em sobreviventes de linfoma não Hodgkin (LNH) tratados com antraciclina manifesta-se por insuficiência cardíaca (IC), definida pela redução da fração de ejeção do ventrículo esquerdo (FEVE). Estes pacientes podem apresentar tardiamente sinais sugestivos de cardiotoxicidade, ainda que não manifestem clínica de IC ou redução da FEVE. O estudo da função cardiovascular por meio da utilização de métodos diagnósticos mais sensíveis para a detecção de disfunção miocárdica precoce poderia contribuir com a prevenção e tratamento da cardiotoxicidade. Objetivos: avaliar sinais de cardiotoxicidade subclínica tardia em pacientes com diagnóstico prévio de LNH tratados com antraciclina por meio de exame clínico e laboratorial com biomarcadores cardíacos, ecocardiografia transtorácica bidimensional com speckle tracking, ultrassonografia de carótidas e teste ergométrico; relacionar os índices de função miocárdica derivados da ecocardiografia com speckle tracking com a capacidade de exercício estimada pelo teste ergométrico. Metodologia: ensaio clínico controlado não randomizado, 1:2, que incluiu sobreviventes de LNH tratados com antraciclina há mais de 1 ano, sem diagnóstico prévio de IC (grupo antraciclina) e indivíduos saudáveis (grupo controle), pareados por sexo e idade. Para todos os participantes do estudo foram avaliados: sinais e sintomas clínicos de IC, fatores de risco e escore de risco cardiovascular, uso de medicações, exames bioquímicos sanguíneos, teste com esteira ergométrica, ultrassonografia de carótidas para obtenção da espessura íntima média das carótidas comuns e ecocardiograma transtorácico com medidas tradicionais, entre elas a FEVE pelo método de Simpson, além da determinação de strain global longitudinal bidimensional (SGL) por speckle tracking. Resultados: o grupo antraciclina foi constituído por 28 indivíduos com idade média... / Abstract: Background: late cardiotoxicity in non-Hodgkin lymphoma survivors (NHL) treated with anthracycline is manifested by heart failure (HF), defined by reduced left ventricular ejection fraction (LVEF). These patients may show signs suggestive of late cardiotoxicity, although not express clinic HF or reduced LVEF. The study of the cardiovascular function through the use of more sensitive diagnostic methods for the early detection of myocardial dysfunction may contribute to the prevention and treatment of cardiotoxicity. Objectives: to evaluate late subclinical cardiotoxicity signals in patients previously diagnosed with NHL treated with anthracycline through clinical and laboratory examination with cardiac biomarkers, two-dimensional transthoracic speckle tracking echocardiography, carotid ultrasound and treadmill test; to relate the derived myocardial function indexes of speckle tracking echocardiography with exercise capacity estimated by treadmill test. Methodology: non-randomized controlled trial, 1: 2, which included NHL survivors treated with anthracycline for more than one year, no previous diagnosis of HF (anthracycline group) and healthy subjects (control group), matched for sex and age. For all study participants were evaluated: clinical signs and symptoms of HF, risk factors and cardiovascular risk score, use of medications, blood biochemical tests, test with treadmill, carotid ultrasound to obtain intima-media thickness of the common carotid and transthoracic echocardiography with traditional measures including LVEF using the Simpson method, and the determination of two-dimensional global longitudinal strain (GLS) by speckle tracking. Results: the anthracycline group consisted of 28 subjects with a mean age of 52 (44; 65) years, 64% male, with a cumulative total dose of 386 (200; 400) mg/m2 of doxorubicin, and 63 subjects in the control group. The groups did not differ with respect to clinical examination, risk factors, ... / Doutor

Objective: Challenging differential diagnosis Background: B cell lymphoma constitutes 80-85% of cases of Non Hodgkin's lymphoma in the Untied States. Metabolic complications may arise from the disease itself or through its end organ involvement. Case Report: We describe a case of a diffuse large B cell lymphoma diagnosed by abdominal computed tomography after it initially presented as hypoglycemia not correctable by dextrose infusion that instead resulted in increased anion gap metabolic acidosis with elevated lactate levels. Conclusions: The case illustrates how lymphomas can present unusually with hypoglycemia and lactic acidosis, the latter being an ominous sign that can occur without liver involvement. In this regard, the case demonstrates the metabolic sequelae of lymphoma that should raise suspicion for an underlying process. This has implications for diagnosis, treatment, and patient survival. Attention should be paid especially in the primary care setting in order to minimize delays in diagnosis.