<p>Lymphomas are a heterogeneous group of neoplasias originating from B- or T-lymphocytes. In this thesis, we determined the genetic and immunophenotypic characterization of DLBCL and their prognostic impact. Moreover, genomic alterations associated with the transformation to DLBCL from Hodgkin lymphoma (HL) and follicular lymphoma (FL) were elucidated. </p><p>In order to outline the impact of cytogenetic as well as immunophenotypic prognostic markers in DLBCL, we firstly studied a series of 54 DLBCL tumors using comparative genomic hybridization (CGH) and we identified several frequently occurring chromosomal imbalances. Loss of 22q was more often found in the diagnostic tumors with a more advanced clinical stage, while gain of 18q21 was more commonly identified in relapses. Secondly, we correlated the expression patterns of CD10, bcl-6, IRF-4 and bcl-2 with clinical parameters in a series of 173 de novo DLBCL patients. Patients with a germinal center (GC) phenotype displayed a better survival than the non-GC group. Expression of bcl-6 and CD10 was correlated with a better survival while bcl-2 expression was associated with a poor prognosis.</p><p>In approaching the HL transformation, two novel B-cell lines (U-2932 and U-2940), derived from patients with DLBCL following HL, were characterized. Interestingly, a translocation with materials from 2q and 7q as well as loss of material on 6q was found in both cell lines. For FL transformation, we assessed chromosomal alterations in a panel of 28 DLBCL patients with a previous history of FL. The DLBCL tumors displayed more chromosomal imbalances compared to FL tumors. Loss of 6q16-21 and gain of 7pter-q22 were more commonly found in the DLBCL counterparts, suggesting the chromosomal location of putative genes that may be involved in the transformation process.</p>

Lymphomas are a heterogeneous group of neoplasias originating from B- or T-lymphocytes. In this thesis, we determined the genetic and immunophenotypic characterization of DLBCL and their prognostic impact. Moreover, genomic alterations associated with the transformation to DLBCL from Hodgkin lymphoma (HL) and follicular lymphoma (FL) were elucidated. In order to outline the impact of cytogenetic as well as immunophenotypic prognostic markers in DLBCL, we firstly studied a series of 54 DLBCL tumors using comparative genomic hybridization (CGH) and we identified several frequently occurring chromosomal imbalances. Loss of 22q was more often found in the diagnostic tumors with a more advanced clinical stage, while gain of 18q21 was more commonly identified in relapses. Secondly, we correlated the expression patterns of CD10, bcl-6, IRF-4 and bcl-2 with clinical parameters in a series of 173 de novo DLBCL patients. Patients with a germinal center (GC) phenotype displayed a better survival than the non-GC group. Expression of bcl-6 and CD10 was correlated with a better survival while bcl-2 expression was associated with a poor prognosis. In approaching the HL transformation, two novel B-cell lines (U-2932 and U-2940), derived from patients with DLBCL following HL, were characterized. Interestingly, a translocation with materials from 2q and 7q as well as loss of material on 6q was found in both cell lines. For FL transformation, we assessed chromosomal alterations in a panel of 28 DLBCL patients with a previous history of FL. The DLBCL tumors displayed more chromosomal imbalances compared to FL tumors. Loss of 6q16-21 and gain of 7pter-q22 were more commonly found in the DLBCL counterparts, suggesting the chromosomal location of putative genes that may be involved in the transformation process.

A família paraoxonase (PON1, PON2 e PON3) tem sido objeto de grande interesse por prevenir o estresse oxidativo e o processo inflamatório, condições importantes na carcinogênese. O Linfoma Difuso de Grandes Células B (LDGCB) consiste no subtipo histológico mais comum dentre os linfomas, doenças que se originam a partir das células do tecido linfoide e exibem distintos comportamentos clínicos, fatores patológicos e características epidemiológicas. Há escassez de dados sobre a atuação das paraoxonases na susceptibilidade diferencial ao risco de linfomas. Deste modo, o objetivo do presente estudo foi investigar a frequência alélica e genotípica dos polimorfismos 192QR e 55LM, no gene da PON1, e 148AG e 311SC, no gene da PON2 e o efeito desses polimorfismos sobre as atividades da enzima PON e perfil lipídico em 182 indivíduos (78 pacientes com LDGCB e 104 indivíduos saudáveis). O sangue foi coletado, em 4 momentos, para a determinação do perfil lipídico e das atividades arilesterase e paraoxonase da PON. O DNA foi extraído de leucócitos do sangue periférico pelo método de extração salina. A análise dos polimorfismos foi realizada por PCR/RFLP. Não houve diferença estatística na distribuição de genótipos e frequência de alelos dos polimorfismos nos genes da PON1 e PON2. A atividade sérica da arilesterase apresentou valores significativamente maiores apenas entre os indivíduos saudáveis (p=0,001). As variantes 55MM e 192QQ, do gene da PON1, influenciaram as atividades arilesterase (p=0,011) e paraoxonase (0,001). O polimorfismo PON2 311SS associou-se a atividade arilesterase (p=0,021). A concentração de autoanticorpos oxLDL foi alterada, pela presença do genótipo 55LM (p=0,037) nos indivíduos com LDGCB / The paraoxonase family (PON1, PON2 and PON3) have been the subject of great interest, since they are responsible for preventing oxidative stress and inflammation, conditions important in carcinogenesis. The Diffuse Large B Cell Lymphoma (DLBCL) is the most common histological subtype among lymphomas, diseases that originate from cells of the lymphoid tissue and exhibit clinically distinct behaviors and pathological and epidemiological factors. There are paucity of data on the activity of paraoxonase in the differential susceptibility to the risk of lymphoma. Thus, the objective of this study was to investigate the genotypic and allelic frequency of polymorphisms 192QR and 55LM, in the PON1 gene and 148AG and 311SC, in the PON2 gene and the effect of these polymorphisms on PON enzyme activities and lipid profile in 182 subjects (78 patients with DLBCL and 104 healthy subjects). Blood was collected in four moments for the determination of lipid profile and paraoxonase and arylesterase activities of PON. The DNA was extracted from peripheral blood leukocytes by salt extraction method. The analysis of polymorphisms was performed by PCR/RFLP. There was no statistical difference in the distribution of genotypes and allele frequencies of polymorphisms in the PON1 and PON2 genes. The serum arylesterase activity was significantly higher only among healthy subjects (p=0.001). 192QQ and 55MM variants of the PON1 gene, influenced arylesterase (p=0.011) and paraoxonase (0.001) activities. The PON2 polymorphism was associated with 311SS arylesterase activity (p = 0.021). The concentration of oxLDL autoantibodies was altered by the presence of 55LM genotype (p = 0.037) in patients with DLBCL

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21451号 / 医博第4418号 / 新制||医||1032(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 椛島 健治, 教授 河本 宏 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Primary gastrointestinal lymphoma is the most common type of extra-nodal lymphoma, representing about 30%-50% of all extra-nodal involvement. The stomach is the most common site, with the colon and rectum accounting for a minority of occurrences. Primary colorectal lymphoma is uncommon, representing only 0.3% of all large intestinal malignancies and approximately 3% of gastrointestinal (GI) lymphomas, with the majority of these being B-cell non-Hodgkin lymphoma and diffuse large B-cell lymphoma (DLBCL) being the most common subtype. We present a case of an 85-year-old male who presented with symptoms suggestive of bowel obstruction, who, after further evaluation, was diagnosed with primary non-Hodgkin lymphoma of the colon, DLBCL subtype.

Lymphomas are malignant tumours arising from cells in the lymphatic system. They are classified as B-cell lymphomas, T-cell lymphomas and Hodgkin lymphoma (HL). Of the B-cell lymphomas, one of the most common is diffuse large B-cell lymphoma (DLBCL). Many patients with lymphomas can be successfully treated however patients who relapse or are refractory have a poor prognosis, warranting further investigations to identify potential targets and develop novel drugs. Picropodophyllin (PPP), a potent and selective inhibitor of IGF-1R, inhibits malignant cell growth with low or no toxicity on normal cells in preclinical models. In paper I, we investigated the potential benefits of using PPP against DLBCL and found that the anti-tumor effects of PPP might possibly be explained by IGF-1R-unrelated mechanism(s). However, the inhibitory effects of PPP on lymphoma cells together with its low toxicity in vivo makes it a promising drug candidate for treatment. Melflufen, a derivative of melphalan, is currently being evaluated in a clinical phase I/II trial in relapsed or refractory multiple myeloma. In paper II, we confirmed previous reports of superior potency of melflufen over melphalan. Being active in cell lines and primary cultures of lymphoma cells as well as in a xenograft model in mice, melflufen considered being a candidate for further evaluation in treatment. bAP-15, a novel inhibitor of proteasome activity, inhibits ubiquitin specific peptidase 14 (USP14) and ubiquitin carboxyl-terminal hydrolase L5 (UCHL5). In paper III, we investigated the activity of b-AP15 in DLBCL and HL cell lines and compared the results to standard drugs used in treatment. Results showed inhibition of the proteasome and growth inhibition/cytotoxicity with IC50-values in the micromolar range. Treatment failure and lack of clinical benefit of proteasome inhibitors like bortezomib in DLBCL patients inspired us investigating for possible new targets, with major focus on proteasome inhibitors in DLBCL. In paper IV, we suggested that UCHL5 and/or USP14, as new targets for proteasome inhibitors in DLBCL, be further evaluated. The findings in this thesis suggest that PPP, Melflufen and b-AP15 are potential candidates for clinical drug development and UCHL5 and/or USP14 are new potential targets for proteasome inhibitors in DLBCL.

Purpose: To investigate if apparent diffusion coefficient (ADC) values within primary central nervous system lymphoma correlate with cellularity and proliferative activity in corresponding histological samples. Materials and Methods: Echo-planar diffusion-weighted magnetic resonance images obtained from 21 patients with primary central nervous system lymphoma were reviewed retrospectively. Regions of interest were drawn on ADC maps corresponding to the contrast enhancing parts of the tumors. Biopsies from all 21 patients were histologically analyzed. Nuclei count, total nuclei area and average nuclei area were measured. The proliferation index was estimated as Ki-67 positive nuclei divided by total number of nuclei. Correlations of ADC values and histopathologic parameters were determined statistically. Results: Ki-67 staining revealed a statistically significant correlation with ADCmin (r = -0.454, p = 0.038), ADCmean (r = -0.546, p = 0.010) and ADCmax (r = -0.515, p = 0.017). Furthermore, ADCmean correlated in a statistically significant manner with total nucleic area (r = -0.500, p = 0.021). Conclusion: Low ADCmin, ADCmean and ADCmax values reflect a high proliferative activity of primary cental nervous system lymphoma. Low ADCmean values—in concordance with several previously published studies—indicate an increased cellularity within the tumor.

Orientador: Maria Aparecida Custódio Domingues / Resumo: O linfoma difuso de grandes células B (LDGCB) integra o grupo das neoplasias malignas hematopoiéticas classificado como linfomas não-Hodgkin e representa o subtipo mais prevalente no Brasil e no mundo. Ao seu diagnóstico, segue-se um estadiamento clínico denominado Classificação de Ann-Arbor/Lugano, visando estimar o tratamento. Neste estadiamento, além de exames laboratoriais, parâmetros clínicos e imagens radiológicas, faz-se avaliação da medula óssea (MO) para pesquisa de infiltração neoplásica. O presente estudo comparou a análise unicamente morfológica da MO em relação à combinação da morfologia com imunoistoquímica (IHQ) na detecção de infiltração neoplásica medular em pacientes com LDGCB. Para isso, realizou-se levantamento retrospectivo de 113 pacientes diagnosticados com LDGCB submetidos a biópsia/aspirado de MO para estadiamento. Informações clínicas foram levantadas nos prontuários médicos e as lâminas histológicas de biópsias e coágulos de MO foram revisadas quanto a seus aspectos morfológicos. Procedeu-se estudo IHQ com os marcadores CD20 e CD3, sendo este o padrão ouro. A sensibilidade da análise morfológica isolada foi de 42,9%, considerada baixa se considerarmos que esta serviria como um exame de triagem. A quantidade de acúmulos linfoides (AcL) na MO e o aumento de trama reticulínica no acúmulo linfoide mostraram p-valor respectivamente de 0,02, para uma mediana de 2 acúmulos, e 0,01 para uma mediana de trama reticulínica de II, mostrando assim existir uma re... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Diffuse Large B Cell Lymphoma (DLBCL) belongs to a group of hematopoietic malignancies called Non-Hodgkin's Lymphomas, being the most prevalent in Brazil. After the diagnosis is followed a staging, called Ann-Arbor/Lugano classification, aiming to estimate the treatment. This staging, in addition to laboratory exams, clinical parameters and radiological images, includes the histological evaluation of bone marrow (BM) for the investigation of neoplastic infiltration. The present study compared BM morphological analysis only and morphology combined with immunohistochemistry (IHC) to detect BM infiltration in patients with DLBCL. For this, a retrospective survey was performed on 113 patients diagnosed with LDGCB submitted to biopsy / aspiration for BM staging. Clinical information was reviewed from medical records and histological biopsy and clots were reviewed for morphological aspects. The IHQ study was performed with CD20 and CD3 markers. The sensitivity of the isolated morphological analysis was 42.9%, considered low if we remember that this evaluation would serve as a screening test. The amount of lymphoid agreggates in BM and the increase in reticulin stain into the lymphoid agreggates showed p-value respectively of 0.02 and a median of 2 agreggates and 0.01 for a grade II reticulin, thus showing a relation of these two morphological parameters with BM infiltration. After this, we can conclude that the isolated morphological analysis is not recommended, and should always b... (Complete abstract click electronic access below) / Mestre

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1 ABSTRACT B-cell non-Hodgkin lymphomas (B-NHL) represent the most common mature lymphoproliferative diseases. B-NHL arise at different stages of B-cell development and represent their malignant counterpart. Diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) are aggressive types of B-NHLs. Deregulation of cell cycle control, inhibition of apoptosis or abnormal DNA damage response play a key role in the pathogenesis of DLBCL and MCL. Aberrant activation of several signaling pathways that further promote survival, cell proliferation or affect the tumor microenvironment have been recently recognized. Increased understanding of the oncogenic mechanisms implicated in pathogenesis of B-NHL lead to development of novel agents that target the oncogenic drivers of distinct lymphoma subtypes. MCL is an aggressive subtype of B-NHL associated with poor prognosis. In vivo models of human MCL for experimental therapy are however scarce. We established and characterized several mouse models of human MCL by xenotransplantation of either primary cells or established cell lines into immunodeficient mice (publication no 1). We demonstrated that engrafted MCL cells displayed complex changes of gene expression profile, phenotype and sensitivity to cytotoxic agents compared to the original in vitro growing...