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1.
Cell ; 155(3): 567-81, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-24139898

RESUMO

Mutation is a fundamental process in tumorigenesis. However, the degree to which the rate of somatic mutation varies across the human genome and the mechanistic basis underlying this variation remain to be fully elucidated. Here, we performed a cross-cancer comparison of 402 whole genomes comprising a diverse set of childhood and adult tumors, including both solid and hematopoietic malignancies. Surprisingly, we found that the inactive X chromosome of many female cancer genomes accumulates on average twice and up to four times as many somatic mutations per megabase, as compared to the individual autosomes. Whole-genome sequencing of clonally expanded hematopoietic stem/progenitor cells (HSPCs) from healthy individuals and a premalignant myelodysplastic syndrome (MDS) sample revealed no X chromosome hypermutation. Our data suggest that hypermutation of the inactive X chromosome is an early and frequent feature of tumorigenesis resulting from DNA replication stress in aberrantly proliferating cells.


Assuntos
Cromossomos Humanos X , Mutação , Neoplasias/genética , Inativação do Cromossomo X , Adulto , Idoso , Replicação do DNA , Feminino , Humanos , Masculino , Meduloblastoma/genética , Meduloblastoma/patologia , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Polimorfismo de Nucleotídeo Único , Fase S
2.
Nature ; 610(7932): 519-525, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36261548

RESUMO

Genomic analyses of Neanderthals have previously provided insights into their population history and relationship to modern humans1-8, but the social organization of Neanderthal communities remains poorly understood. Here we present genetic data for 13 Neanderthals from two Middle Palaeolithic sites in the Altai Mountains of southern Siberia: 11 from Chagyrskaya Cave9,10 and 2 from Okladnikov Cave11-making this one of the largest genetic studies of a Neanderthal population to date. We used hybridization capture to obtain genome-wide nuclear data, as well as mitochondrial and Y-chromosome sequences. Some Chagyrskaya individuals were closely related, including a father-daughter pair and a pair of second-degree relatives, indicating that at least some of the individuals lived at the same time. Up to one-third of these individuals' genomes had long segments of homozygosity, suggesting that the Chagyrskaya Neanderthals were part of a small community. In addition, the Y-chromosome diversity is an order of magnitude lower than the mitochondrial diversity, a pattern that we found is best explained by female migration between communities. Thus, the genetic data presented here provide a detailed documentation of the social organization of an isolated Neanderthal community at the easternmost extent of their known range.


Assuntos
Homem de Neandertal , Animais , Feminino , Humanos , Cavernas , Genoma/genética , Hibridização Genética , Homem de Neandertal/genética , Sibéria , DNA Mitocondrial/genética , Cromossomo Y/genética , Masculino , Família , Homozigoto
3.
Nature ; 595(7867): 399-403, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34163072

RESUMO

Denisova Cave in southern Siberia is the type locality of the Denisovans, an archaic hominin group who were related to Neanderthals1-4. The dozen hominin remains recovered from the deposits also include Neanderthals5,6 and the child of a Neanderthal and a Denisovan7, which suggests that Denisova Cave was a contact zone between these archaic hominins. However, uncertainties persist about the order in which these groups appeared at the site, the timing and environmental context of hominin occupation, and the association of particular hominin groups with archaeological assemblages5,8-11. Here we report the analysis of DNA from 728 sediment samples that were collected in a grid-like manner from layers dating to the Pleistocene epoch. We retrieved ancient faunal and hominin mitochondrial (mt)DNA from 685 and 175 samples, respectively. The earliest evidence for hominin mtDNA is of Denisovans, and is associated with early Middle Palaeolithic stone tools that were deposited approximately 250,000 to 170,000 years ago; Neanderthal mtDNA first appears towards the end of this period. We detect a turnover in the mtDNA of Denisovans that coincides with changes in the composition of faunal mtDNA, and evidence that Denisovans and Neanderthals occupied the site repeatedly-possibly until, or after, the onset of the Initial Upper Palaeolithic at least 45,000 years ago, when modern human mtDNA is first recorded in the sediments.


Assuntos
Cavernas , DNA Antigo/análise , Sedimentos Geológicos/química , Hominidae/genética , Animais , Arqueologia , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Fósseis , História Antiga , Homem de Neandertal/genética , Sibéria
4.
Nature ; 592(7853): 253-257, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33828320

RESUMO

Modern humans appeared in Europe by at least 45,000 years ago1-5, but the extent of their interactions with Neanderthals, who disappeared by about 40,000 years ago6, and their relationship to the broader expansion of modern humans outside Africa are poorly understood. Here we present genome-wide data from three individuals dated to between 45,930 and 42,580 years ago from Bacho Kiro Cave, Bulgaria1,2. They are the earliest Late Pleistocene modern humans known to have been recovered in Europe so far, and were found in association with an Initial Upper Palaeolithic artefact assemblage. Unlike two previously studied individuals of similar ages from Romania7 and Siberia8 who did not contribute detectably to later populations, these individuals are more closely related to present-day and ancient populations in East Asia and the Americas than to later west Eurasian populations. This indicates that they belonged to a modern human migration into Europe that was not previously known from the genetic record, and provides evidence that there was at least some continuity between the earliest modern humans in Europe and later people in Eurasia. Moreover, we find that all three individuals had Neanderthal ancestors a few generations back in their family history, confirming that the first European modern humans mixed with Neanderthals and suggesting that such mixing could have been common.


Assuntos
DNA Antigo/análise , Genoma Humano/genética , Homem de Neandertal/genética , Alelos , América/etnologia , Animais , Arqueologia , Bulgária/etnologia , Cavernas , Ásia Oriental/etnologia , Feminino , História Antiga , Humanos , Masculino , Filogenia
5.
Blood ; 144(2): 187-200, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38620074

RESUMO

ABSTRACT: SRY-related HMG-box gene 11 (SOX11) is a transcription factor overexpressed in mantle cell lymphoma (MCL), a subset of Burkitt lymphomas (BL) and precursor lymphoid cell neoplasms but is absent in normal B cells and other B-cell lymphomas. SOX11 has an oncogenic role in MCL but its contribution to BL pathogenesis remains uncertain. Here, we observed that the presence of Epstein-Barr virus (EBV) and SOX11 expression were mutually exclusive in BL. SOX11 expression in EBV-negative (EVB-) BL was associated with an IG∷MYC translocation generated by aberrant class switch recombination, whereas in EBV-negative (EBV-)/SOX11-negative (SOX11-) tumors the IG∷MYC translocation was mediated by mistaken somatic hypermutations. Interestingly, EBV- SOX11-expressing BL showed higher frequency of SMARCA4 and ID3 mutations than EBV-/SOX11- cases. By RNA sequencing, we identified a SOX11-associated gene expression profile, with functional annotations showing partial overlap with the SOX11 transcriptional program of MCL. Contrary to MCL, no differences on cell migration or B-cell receptor signaling were found between SOX11- and SOX11-positive (SOX11+) BL cells. However, SOX11+ BL showed higher adhesion to vascular cell adhesion molecule 1 (VCAM-1) than SOX11- BL cell lines. Here, we demonstrate that EBV- BL comprises 2 subsets of cases based on SOX11 expression. The mutual exclusion of SOX11 and EBV, and the association of SOX11 with a specific genetic landscape suggest a role of SOX11 in the early pathogenesis of BL.


Assuntos
Linfoma de Burkitt , Herpesvirus Humano 4 , Fatores de Transcrição SOXC , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/virologia , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo , Herpesvirus Humano 4/genética , Regulação Neoplásica da Expressão Gênica , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Mutação , DNA Helicases/genética , DNA Helicases/metabolismo , Translocação Genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Masculino , Proteínas Inibidoras de Diferenciação/genética , Proteínas Inibidoras de Diferenciação/metabolismo , Proteínas Nucleares
6.
Proc Natl Acad Sci U S A ; 120(9): e2204933120, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36812208

RESUMO

N6-methyladenosine (m6A) regulates mRNA metabolism. While it has been implicated in the development of the mammalian brain and in cognition, the role of m6A in synaptic plasticity, especially during cognitive decline, is not fully understood. In this study, we employed methylated RNA immunoprecipitation sequencing to obtain the m6A epitranscriptome of the hippocampal subregions CA1, CA3, and the dentate gyrus and the anterior cingulate cortex (ACC) in young and aged mice. We observed a decrease in m6A levels in aged animals. Comparative analysis of cingulate cortex (CC) brain tissue from cognitively intact human subjects and Alzheimer's disease (AD) patients showed decreased m6A RNA methylation in AD patients. m6A changes common to brains of aged mice and AD patients were found in transcripts linked to synaptic function including calcium/calmodulin-dependent protein kinase 2 (CAMKII) and AMPA-selective glutamate receptor 1 (Glua1). We used proximity ligation assays to show that reduced m6A levels result in decreased synaptic protein synthesis as exemplified by CAMKII and GLUA1. Moreover, reduced m6A levels impaired synaptic function. Our results suggest that m6A RNA methylation controls synaptic protein synthesis and may play a role in cognitive decline associated with aging and AD.


Assuntos
Doença de Alzheimer , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Humanos , Camundongos , Animais , Idoso , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Hipocampo/metabolismo , Doença de Alzheimer/metabolismo , Envelhecimento/metabolismo , RNA/metabolismo , Mamíferos/genética
7.
J Pathol ; 262(2): 189-197, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37933684

RESUMO

Primary cutaneous CD4+ small or medium T-cell lymphoproliferative disorder (PCSM-LPD) is a clonal T-cell proliferation disease confined to the skin. PCSM-LPD shares expression of T follicular helper (Tfh) cell markers with various mature T-cell lymphomas. However, the benign presentation of PCSM-LPD contrasts the clinical behavior of other Tfh-lymphomas. The aim of our study was to delineate the molecular similarities and differences between PCSM-LPD and other Tfh-derived lymphomas to explain the clinical behavior and unravel possible pathological mechanisms. We performed targeted next-generation sequencing of 19 genes recurrently mutated in T-cell neoplasms in n = 17 PCSM-LPD with high and in n = 21 PCSM-LPD with low tumor cell content. Furthermore, gene expression profiling was used to identify genes potentially expressed in the PD1-positive (PD1+) neoplastic cells. Expression of some of these genes was confirmed in situ using multistain immunofluorescence. We found that PCSM-LPD rarely harbored mutations recurrently detected in other T-cell neoplasms. PCSM-LPD is characterized by the invariable expression of the T-cell-receptor-associated LCK protein. CD70 and its ligand CD27 are co-expressed on PD1+ PCSM-LPD cells, suggestive of autoactivation of the CD70 pathway. In conclusion, PCSM-LPD differs from disseminated lymphomas of Tfh origin by their mutation profile. Activation of CD70 signaling also found in cutaneous T-cell lymphoma represents a potential driver of neoplastic proliferation of this benign neoplasia of Tfh. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Linfoma Cutâneo de Células T , Transtornos Linfoproliferativos , Dermatopatias , Neoplasias Cutâneas , Humanos , Linfócitos T CD4-Positivos/patologia , Dermatopatias/patologia , Linfoma Cutâneo de Células T/genética , Linfoma Cutâneo de Células T/patologia , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Ligante CD27/genética
8.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34969841

RESUMO

Ancient DNA recovered from Pleistocene sediments represents a rich resource for the study of past hominin and environmental diversity. However, little is known about how DNA is preserved in sediments and the extent to which it may be translocated between archaeological strata. Here, we investigate DNA preservation in 47 blocks of resin-impregnated archaeological sediment collected over the last four decades for micromorphological analyses at 13 prehistoric sites in Europe, Asia, Africa, and North America and show that such blocks can preserve DNA of hominins and other mammals. Extensive microsampling of sediment blocks from Denisova Cave in the Altai Mountains reveals that the taxonomic composition of mammalian DNA differs drastically at the millimeter-scale and that DNA is concentrated in small particles, especially in fragments of bone and feces (coprolites), suggesting that these are substantial sources of DNA in sediments. Three microsamples taken in close proximity in one of the blocks yielded Neanderthal DNA from at least two male individuals closely related to Denisova 5, a Neanderthal toe bone previously recovered from the same layer. Our work indicates that DNA can remain stably localized in sediments over time and provides a means of linking genetic information to the archaeological and ecological records on a microstratigraphic scale.


Assuntos
Cavernas , DNA Antigo , Fósseis , Hominidae/genética , Homem de Neandertal/genética , Animais
9.
Br J Haematol ; 204(5): 1894-1898, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38279625

RESUMO

Frequency, distribution and prognostic meaning of ALK-partner genes other than NPM1 in ALK-positive anaplastic large-cell lymphoma (ALCL) are unknown. Forty-nine of 316 ALCL diagnosed in the NHL-BFM study group showed no nuclear ALK expression suggestive of a variant ALK-partner; 41 were analysed by genomic capture high-throughput sequencing or specific RT-PCRs. NPM1::ALK was detected in 13 cases. Among the 28 patients with a non-NPM1::ALK-fusion partner, ATIC (n = 8; 29%) and TPM3 (n = 9; 32%) were the most common. Five of eight patients with ATIC::ALK-positive ALCL relapsed, none of nine with TPM3::ALK. Variant ALK-partners are rare and potentially associated with different prognoses.


Assuntos
Quinase do Linfoma Anaplásico , Linfoma Anaplásico de Células Grandes , Nucleofosmina , Humanos , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/patologia , Criança , Masculino , Feminino , Quinase do Linfoma Anaplásico/genética , Quinase do Linfoma Anaplásico/análise , Adolescente , Pré-Escolar , Proteínas de Fusão Oncogênica/genética , Prognóstico , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Lactente , Tropomiosina
10.
Histopathology ; 82(3): 485-494, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36341542

RESUMO

AIMS: The aim was to gain insight into the biology of primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder (PCSM-LPD). METHODS: We describe the histopathological and clinical characteristics of 177 PCSM-LPD diagnosed at our consultation centre. We performed immunohistochemical multistaining in a subset of cases (n = 46) including PD1, Cyclin D1, and multiple markers of proliferation. We evaluated clonal T-cell-receptor-(TCR) rearrangements and used tissue microdissection to analyse TCR-clonality of PD1(+) cells. RESULTS: The cohort of n = 177 PCSM-LPD included 84 males and 93 females (median age 57, range 13-85). Clinical presentation was as a solitary nodule or plaque (head and neck > trunk > extremities). Most patients were treated by local excision or steroids (96%, 69/72); relapses occurred in 12/65 (18%) of patients with follow up. Histopathology revealed the predominance of a nodular pattern (75%, 134/177) and frequent clustering of PD1(+) large cells (70%, 103/147). We detected Cyclin D1 and PD1 coexpression (>10% of PD1(+)-cells) in 26/46 (57%), which was not associated with CCND1 breaks or amplifications. PD1(+)-cells in PCSM-LPDs showed a significantly higher expression of proliferation-associated proteins compared to PD1(-)-cells. A clonal TCR-rearrangement was present in 176/177 (99%), with a clonal persistence in 7/8 patients at relapse including distant sites. Tissue-microdissection revealed PD1(+)-cells as the source of clonality, whilst PD1(-)-cells remained polyclonal. CONCLUSION: PCSM-LPD is a clinically indolent, albeit neoplastic, disease driven by clonal expansion of PD1(+)-cells. We demonstrate Cyclin D1-expression associated with accelerated proliferation as a surprising new biological feature of the disease.


Assuntos
Ciclina D1 , Linfoma Cutâneo de Células T , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linfócitos T CD4-Positivos/patologia , Proliferação de Células , Ciclina D1/genética , Ciclina D1/metabolismo , Linfoma Cutâneo de Células T/genética , Linfoma Cutâneo de Células T/metabolismo , Linfoma Cutâneo de Células T/patologia , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/metabolismo , Transtornos Linfoproliferativos/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
11.
Ann Hematol ; 102(12): 3445-3455, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37566280

RESUMO

In diffuse large B-cell lymphoma (DLBCL), a positive interim positron emission tomography (PET) scan predicts treatment failure, but the proportion of high-risk patients thus identified is small. To improve prediction, we combined the interim PET result with the presence or absence of an associated IgM gammopathy. Of 108 DLBCL patients participating in a prospective trial, nine (8%) were interim PET positive and 19 (18%) had an IgM gammopathy. The monoclonal protein was not associated with distinguishing genetic features, and its light chain restriction was not always concordant with the light chain restriction of the lymphoma. The information provided by interim PET and IgM gammopathy was combined to dichotomize the population into sizeable high-risk (1-2 adverse factors) and low-risk groups (no adverse factor) with widely different outcomes (population size, 25% vs. 75%; 3-year risk of progression, 51% vs. 10%; 3-year overall survival, 64% vs. 95%). Multivariable analyses including established risk factors revealed the interim PET result and the IgM gammopathy status to be the only factors significantly associated with outcome. Information about interim PET response and IgM gammopathy may be useful in studies testing risk-adapted treatment strategies.


Assuntos
Linfoma Difuso de Grandes Células B , Paraproteinemias , Humanos , Estudos Prospectivos , Prognóstico , Tomografia por Emissão de Pósitrons/métodos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Paraproteinemias/diagnóstico por imagem , Imunoglobulina M , Fluordesoxiglucose F18/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
12.
Sensors (Basel) ; 23(19)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37837046

RESUMO

Due to the growing interest in climbing, increasing importance has been given to research in the field of non-invasive, camera-based motion analysis. While existing work uses invasive technologies such as wearables or modified walls and holds, or focuses on competitive sports, we for the first time present a system that uses video analysis to automatically recognize six movement errors that are typical for novices with limited climbing experience. Climbing a complete route consists of three repetitive climbing phases. Therefore, a characteristic joint arrangement may be detected as an error in a specific climbing phase, while this exact arrangement may not considered to be an error in another climbing phase. That is why we introduced a finite state machine to determine the current phase and to check for errors that commonly occur in the current phase. The transition between the phases depends on which joints are being used. To capture joint movements, we use a fourth-generation iPad Pro with LiDAR to record climbing sequences in which we convert the climber's 2-D skeleton provided by the Vision framework from Apple into 3-D joints using the LiDAR depth information. Thereupon, we introduced a method that derives whether a joint moves or not, determining the current phase. Finally, the 3-D joints are analyzed with respect to defined characteristic joint arrangements to identify possible motion errors. To present the feedback to the climber, we imitate a virtual mentor by realizing an application on the iPad that creates an analysis immediately after the climber has finished the route by pointing out the detected errors and by giving suggestions for improvement. Quantitative tests with three experienced climbers that were able to climb reference routes without any errors and intentionally with errors resulted in precision-recall curves evaluating the error detection performance. The results demonstrate that while the number of false positives is still in an acceptable range, the number of detected errors is sufficient to provide climbing novices with adequate suggestions for improvement. Moreover, our study reveals limitations that mainly originate from incorrect joint localizations caused by the LiDAR sensor range. With human pose estimation becoming increasingly reliable and with the advance of sensor capabilities, these limitations will have a decreasing impact on our system performance.

13.
Br J Haematol ; 196(3): 681-689, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34617271

RESUMO

Sporadic Burkitt lymphoma (BL) is the most frequent tumour of children and adolescents but a rare subtype of lymphomas in adults. To date most molecular data have been obtained from lymphomas arising in the young. Recently, Epstein-Barr virus (EBV) positive and negative BL in young patients was shown to differ in molecular features. In the present study, we present a large age-overarching cohort of sporadic BL (n = 162) analysed by immunohistochemistry, translocations of MYC proto-oncogene, basic helix-loop-helix transcription factor (MYC), B-cell leukaemia/lymphoma 2 (BCL2) and B-cell leukaemia/lymphoma 6 (BCL6) and by targeted sequencing. We illustrate an age-associated inter-tumoral molecular heterogeneity in this disease. Mutations affecting inhibitor of DNA binding 3, HLH protein (ID3), transcription factor 3 (TCF3) and cyclin D3 (CCND3), which are highly recurrent in paediatric BL, and expression of sex determining region Y-box transcription factor 11 (SOX11) declined with patient age at diagnosis (P = 0·0204 and P = 0·0197 respectively). In contrast, EBV was more frequently detected in adult patients (P = 0·0262). Irrespective of age, EBV-positive sporadic BL showed significantly less frequent mutations in ID3/TCF3/CCND3 (P = 0·0088) but more often mutations of G protein subunit alpha 13 (GNA13; P = 0·0368) and forkhead box O1 (FOXO1; P = 0·0044) compared to EBV-negative tumours. Our findings suggest that among sporadic BL an EBV-positive subgroup of lymphomas increases with patient age that shows distinct pathogenic features reminiscent of EBV-positive endemic BL.


Assuntos
Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/etiologia , Suscetibilidade a Doenças , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/fisiologia , Mutação , Adolescente , Adulto , Fatores Etários , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Linfoma de Burkitt/diagnóstico , Transformação Celular Viral , Criança , Pré-Escolar , Análise Mutacional de DNA , Infecções por Vírus Epstein-Barr/virologia , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Blood ; 136(25): 2851-2863, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33113552

RESUMO

Classic Hodgkin lymphoma (cHL) is the cancer type most susceptible to antibodies targeting programmed cell death protein 1 (PD1) and is characterized by scarce Hodgkin and Reed-Sternberg cells (HRSCs), perpetuating a unique tumor microenvironment (TME). Although anti-PD1 effects appear to be largely mediated by cytotoxic CD8+ T cells in solid tumors, HRSCs frequently lack major histocompatibility complex expression, and the mechanism of anti-PD1 efficacy in cHL is unclear. Rapid clinical responses and high interim complete response rates to anti-PD1 based first-line treatment were recently reported for patients with early-stage unfavorable cHL treated in the German Hodgkin Study Group phase 2 NIVAHL trial. To investigate the mechanisms underlying this very early response to anti-PD1 treatment, we analyzed paired biopsies and blood samples obtained from NIVAHL patients before and during the first days of nivolumab first-line cHL therapy. Mirroring the rapid clinical response, HRSCs had disappeared from the tissue within days after the first nivolumab application. The TME already shows a reduction in type 1 regulatory T cells and PD-L1+ tumor-associated macrophages at this early time point of treatment. Interestingly, a cytotoxic immune response and a clonal T-cell expansion were not observed in the tumors or peripheral blood. These early changes in the TME were distinct from alterations found in a separate set of cHL biopsies at relapse during anti-PD1 therapy. We identify a unique very early histologic response pattern to anti-PD1 therapy in cHL that is suggestive of withdrawal of prosurvival factors, rather than induction of an adaptive antitumor immune response, as the main mechanism of action.


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Doença de Hodgkin , Ativação Linfocitária/efeitos dos fármacos , Nivolumabe/administração & dosagem , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T Citotóxicos/imunologia , Microambiente Tumoral , Feminino , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/imunologia , Doença de Hodgkin/patologia , Humanos , Masculino , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T Citotóxicos/patologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/patologia
15.
Haematologica ; 107(9): 2144-2153, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35021600

RESUMO

The sole distinguishing feature of follicular lymphoma grade 3B and diffuse large B-cell lymphoma is the growth pattern assessed by histopathology. Diffuse growth defines diffuse large B-cell lymphoma but the clinical relevance of this finding when occurring in follicular lymphoma grade 3B is uncertain. To address this issue, individual and coexisting follicular lymphoma grade 3B and diffuse large B-cell lymphoma were separated and analyzed for immunophenotype and molecular genetic features by fluorescence in situ hybridization, targeted sequencing and gene expression profiling. Clinical features of follicular lymphoma grade 3B with and without coexisting diffuse large B-cell lymphoma were studied in homogeneously treated patients from a prospective randomized trial. Follicular lymphoma grade 3B and diffuse large B-cell lymphoma frequently show an intermediate growth pattern and/or occur simultaneously in the same tissue at the time of initial diagnosis. When occurring simultaneously follicular lymphoma grade 3B and diffuse large B-cell lymphoma do not differ significantly for genetic aberrations or phenotype but have distinct gene expression features reflecting a divergent microenvironment. Follicular lymphoma grade 3B with and without coexisting diffuse large B-cell lymphoma do not differ for major clinical parameters such as International Prognostic Index, response to immuno-chemotherapy, progression or overall survival. Follicular lymphoma grade 3B and simultaneous diffuse large B-cell lymphoma are molecularly homogenous. Histological detection of diffuse large B-cell lymphoma is not associated with features of a more aggressive disease and does not reflect transformation or progression of follicular lymphoma grade 3B.


Assuntos
Linfoma Folicular , Linfoma Difuso de Grandes Células B , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Linfoma Folicular/diagnóstico , Linfoma Folicular/genética , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Estudos Prospectivos , Microambiente Tumoral/genética
16.
Pediatr Blood Cancer ; 68(11): e29285, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34390161

RESUMO

Non-anaplasticperipheral T-cell lymphomas (PTCL) are rare tumors in children, adolescents, and young adults (CAYA) with poor prognosis and scarce genetic data. We analyzed lymphoma tissue from 36 patients up to 18 years old with PTCL, not otherwise specified (PTCL-NOS), hepatosplenic T-cell lymphoma, Epstein-Barr virus (EBV)-positive T-lymphoproliferative diseases, subcutaneous panniculitis-like T-cell lymphoma, and other PTCL types. Twenty-three patients (64%) had at least one genetic variant detectable, including TET2, KMT2C, PIK3D, and DMNT3A. TP53 and RHOA variants, commonly found in adults, were not identified. Eight of 20 (40%) CAYA PTCL-NOS had no detectable mutations. The genetic findings suggest that CAYA PTCL differ from adult cases.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma de Células T Periférico , Linfoma de Células T , Adolescente , Criança , Herpesvirus Humano 4 , Humanos , Linfoma de Células T/genética , Linfoma de Células T Periférico/genética
17.
Int J Mol Sci ; 21(16)2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32824360

RESUMO

Genome instability is an essential hallmark in tumor development, including colorectal cancer. We have recently identified the oxysterol binding protein-related protein 3 (ORP3), also known as oxysterol binding protein-like 3 (OSBPL3), as a novel ploidy-control gene, whose knock-out leads to aneuploidy induction and promotes tumor formation, indicating that ORP3 is a bona fide tumor suppressor protein. Here we analyzed expression of ORP3 in a cohort (n = 206) of colon cancer patients in relation to patient survival. We show that low ORP3 mRNA levels correlate with reduced survival of patients with advanced nodal metastasis (N2). While patient survival does not associate with grading when the whole cohort is evaluated, importantly, low ORP3 mRNA levels associate with worse survival of female patients with grade 3 colon cancer. Similarly, low ORP3 mRNA levels associate with worse survival of grade 3 colon cancer patients 70 years of age and younger while low ORP3 mRNA levels seem to be beneficial for colon cancer patients with a T2 tumor size. Together, the data show that ORP3 expression is downregulated during colon cancer progression, which correlates with reduced patient survival. Thus, ORP3 mRNA levels may be a prognostic marker for better stratification of colon cancer patients.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Colo/genética , Proteínas de Ligação a Ácido Graxo/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Regulação para Baixo , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Instabilidade Genômica , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores Sexuais
18.
Biol Proced Online ; 21: 13, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303867

RESUMO

BACKGROUND: For analysis of the tumor microenvironment in diffuse large B-cell lymphoma (DLBCL) tissue samples, it is desirable to obtain information about counts and distribution of different macrophage subtypes. Until now, macrophage counts are mostly inferred from gene expression analysis of whole tissue sections, providing only indirect information. Direct analysis of immunohistochemically (IHC) fluorescence stained tissue samples is confronted with several difficulties, e.g. high variability of shape and size of target macrophages and strongly inhomogeneous intensity of staining. Consequently, application of commercial software is largely restricted to very rough analysis modes, and most macrophage counts are still obtained by manual counting in microarrays or high power fields, thus failing to represent the heterogeneity of tumor microenvironment adequately. METHODS: We describe a Rudin-Osher-Fatemi (ROF) filter based segmentation approach for whole tissue samples, combining floating intensity thresholding and rule-based feature detection. Method is validated against manual counts and compared with two commercial software kits (Tissue Studio 64, Definiens AG, and Halo, Indica Labs) and a straightforward machine-learning approach in a set of 50 test images. Further, the novel method and both commercial packages are applied to a set of 44 whole tissue sections. Outputs are compared with gene expression data available for the same tissue samples. Finally, the ROF based method is applied to 44 expert-specified tumor subregions for testing selection and subsampling strategies. RESULTS: Among all tested methods, the novel approach is best correlated with manual count (0.9297). Automated detection of evaluation subregions proved to be fully reliable. Comparison with gene expression data obtained for the same tissue samples reveals only moderate to low correlation levels. Subsampling within tumor subregions is possible with results almost identical to full sampling. Mean macrophage size in tumor subregions is 152.5±111.3 µm2. CONCLUSIONS: ROF based approach is successfully applied to detection of IHC stained macrophages in DLBCL tissue samples. The method competes well with existing commercial software kits. In difference to them, it is fully automated, externally repeatable, independent on training data and completely documented. Comparison with gene expression data indicates that image morphometry constitutes an independent source of information about antibody-polarized macrophage occurence and distribution.

19.
Plant Cell Environ ; 42(1): 295-309, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29940081

RESUMO

Salt-affected farmlands are increasingly burdened by chlorides, carbonates, and sulfates of sodium, calcium, and magnesium. Intriguingly, the underlying physiological processes are studied almost always under NaCl stress. Two faba bean cultivars were subjected to low- and high-salt treatments of NaCl, Na2 SO4 , and KCl. Assimilation rate and leaf water vapor conductance were reduced to approximately 25-30% without biomass reduction after 7 days salt stress, but this did not cause severe carbon shortage. The equimolar treatments of Na+ , K+ , and Cl- showed comparable accumulation patterns in leaves and roots, except for SO42- which did not accumulate. To gain a detailed understanding of the effects caused by the tested ion combinations, we performed nontargeted gas chromatography-mass spectrometry-based metabolite profiling. Metabolic responses to various salts were in part highly linearly correlated, but only a few metabolite responses were common to all salts and in both cultivars. At high salt concentrations, only myo-inositol, allantoin, and glycerophosphoglycerol were highly significantly increased in roots under all tested conditions. We discovered several metabolic responses that were preferentially associated with the presence of Na+ , K+ , or Cl- . For example, increases of leaf proline and decreases of leaf fumaric acid and malic acid were apparently associated with Cl- accumulation.


Assuntos
Estresse Salino , Vicia faba/metabolismo , Cloretos/metabolismo , Metaboloma/fisiologia , Pressão Osmótica , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Transpiração Vegetal/fisiologia , Potássio/metabolismo , Estresse Salino/fisiologia , Sódio/metabolismo , Vicia faba/fisiologia , Água/metabolismo
20.
Nature ; 500(7463): 415-21, 2013 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-23945592

RESUMO

All cancers are caused by somatic mutations; however, understanding of the biological processes generating these mutations is limited. The catalogue of somatic mutations from a cancer genome bears the signatures of the mutational processes that have been operative. Here we analysed 4,938,362 mutations from 7,042 cancers and extracted more than 20 distinct mutational signatures. Some are present in many cancer types, notably a signature attributed to the APOBEC family of cytidine deaminases, whereas others are confined to a single cancer class. Certain signatures are associated with age of the patient at cancer diagnosis, known mutagenic exposures or defects in DNA maintenance, but many are of cryptic origin. In addition to these genome-wide mutational signatures, hypermutation localized to small genomic regions, 'kataegis', is found in many cancer types. The results reveal the diversity of mutational processes underlying the development of cancer, with potential implications for understanding of cancer aetiology, prevention and therapy.


Assuntos
Transformação Celular Neoplásica/genética , Mutagênese/genética , Mutação/genética , Neoplasias/genética , Envelhecimento/genética , Algoritmos , Transformação Celular Neoplásica/patologia , Citidina Desaminase/genética , DNA/genética , DNA/metabolismo , Análise Mutacional de DNA , Humanos , Modelos Genéticos , Mutagênese Insercional/genética , Mutagênicos/farmacologia , Neoplasias/enzimologia , Neoplasias/patologia , Especificidade de Órgãos , Reprodutibilidade dos Testes , Deleção de Sequência/genética , Transcrição Gênica/genética
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