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1.
Cell ; 150(6): 1135-46, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-22980977

RESUMO

DNA methylation at the 5 position of cytosine (5-mC) is a key epigenetic mark that is critical for various biological and pathological processes. 5-mC can be converted to 5-hydroxymethylcytosine (5-hmC) by the ten-eleven translocation (TET) family of DNA hydroxylases. Here, we report that "loss of 5-hmC" is an epigenetic hallmark of melanoma, with diagnostic and prognostic implications. Genome-wide mapping of 5-hmC reveals loss of the 5-hmC landscape in the melanoma epigenome. We show that downregulation of isocitrate dehydrogenase 2 (IDH2) and TET family enzymes is likely one of the mechanisms underlying 5-hmC loss in melanoma. Rebuilding the 5-hmC landscape in melanoma cells by reintroducing active TET2 or IDH2 suppresses melanoma growth and increases tumor-free survival in animal models. Thus, our study reveals a critical function of 5-hmC in melanoma development and directly links the IDH and TET activity-dependent epigenetic pathway to 5-hmC-mediated suppression of melanoma progression, suggesting a new strategy for epigenetic cancer therapy.


Assuntos
Citosina/análogos & derivados , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Melanoma/genética , Nevo/genética , 5-Metilcitosina/análogos & derivados , Citosina/metabolismo , Proteínas de Ligação a DNA/genética , Dioxigenases , Estudo de Associação Genômica Ampla , Humanos , Isocitrato Desidrogenase/genética , Melanócitos/metabolismo , Melanoma/patologia , Nevo/patologia , Proteínas Proto-Oncogênicas/genética
2.
Br J Haematol ; 204(5): 1844-1855, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522849

RESUMO

Recursive partitioning of healthy consortia led to the development of the Clonal Hematopoiesis Risk Score (CHRS) for clonal haematopoiesis (CH); however, in the practical setting, most cases of CH are diagnosed after patients present with cytopenias or related symptoms. To address this real-world population, we characterize the clinical trajectories of 94 patients with CH and distinguish CH harbouring canonical DNMT3A/TET2/ASXL1 mutations alone ('sole DTA') versus all other groups ('non-sole DTA'). TET2, rather than DNMT3A, was the most prevalent mutation in the real-world setting. Sole DTA patients did not progress to myeloid neoplasm (MN) in the absence of acquisition of other mutations. Contrastingly, 14 (20.1%) of 67 non-sole DTA patients progressed to MN. CHRS assessment showed a higher frequency of high-risk CH in non-sole DTA (vs. sole DTA) patients and in progressors (vs. non-progressors). RUNX1 mutation conferred the strongest risk for progression to MN (odds ratio [OR] 10.27, 95% CI 2.00-52.69, p = 0.0053). The mean variant allele frequency across all genes was higher in progressors than in non-progressors (36.9% ± 4.62% vs. 24.1% ± 1.67%, p = 0.0064). This analysis in the post-CHRS era underscores the natural history of CH, providing insight into patterns of progression to MN.


Assuntos
Hematopoiese Clonal , Proteínas de Ligação a DNA , Dioxigenases , Mutação , Humanos , Hematopoiese Clonal/genética , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Proteínas de Ligação a DNA/genética , DNA Metiltransferase 3A , Adulto , Idoso de 80 Anos ou mais , Progressão da Doença , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , DNA (Citosina-5-)-Metiltransferases/genética
3.
Nat Immunol ; 12(3): 213-21, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21278736

RESUMO

Germline mutations in CYBB, the human gene encoding the gp91(phox) subunit of the phagocyte NADPH oxidase, impair the respiratory burst of all types of phagocytes and result in X-linked chronic granulomatous disease (CGD). We report here two kindreds in which otherwise healthy male adults developed X-linked recessive Mendelian susceptibility to mycobacterial disease (MSMD) syndromes. These patients had previously unknown mutations in CYBB that resulted in an impaired respiratory burst in monocyte-derived macrophages but not in monocytes or granulocytes. The macrophage-specific functional consequences of the germline mutation resulted from cell-specific impairment in the assembly of the NADPH oxidase. This 'experiment of nature' indicates that CYBB is associated with MSMD and demonstrates that the respiratory burst in human macrophages is a crucial mechanism for protective immunity to tuberculous mycobacteria.


Assuntos
Genes Ligados ao Cromossomo X , Predisposição Genética para Doença , Macrófagos/imunologia , Glicoproteínas de Membrana/genética , NADPH Oxidases/genética , Tuberculose/genética , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Masculino , Mutação , NADPH Oxidase 2 , NADPH Oxidases/imunologia
4.
Am J Pathol ; 188(4): 846-852, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29353061

RESUMO

Overlapping morphologic, immunohistochemical, and ultrastructural features make it difficult to diagnose chromophobe renal cell carcinoma (ChRCC) and renal oncocytoma (RO). Because ChRCC is a malignant tumor, whereas RO is a tumor with benign behavior, it is important to distinguish these two entities. We aimed to identify genetic markers that distinguish ChRCC from RO by using next-generation sequencing (NGS). NGS for hotspot mutations or gene copy number changes was performed on 12 renal neoplasms, including seven ChRCC and five RO cases. Matched normal tissues from the same patients were used to exclude germline variants. Rare hotspot mutations were found in cancer-critical genes (TP53 and PIK3CA) in ChRCC but not RO. The NGS gene copy number analysis revealed multiple abnormalities. The two most common deletions were tumor-suppressor genes RB1 and ERBB4 in ChRCC but not RO. Fluorescence in situ hybridization was performed on 65 cases (ChRCC, n = 33; RO, n = 32) to verify hemizygous deletion of RB1 (17/33, 52%) or ERBB4 (11/33, 33%) in ChRCC, but not in RO (0/32, 0%). In total, ChRCCs (23/33, 70%) carry either a hemizygous deletion of RB1 or ERBB4. The combined use of RB1 and ERBB4 fluorescence in situ hybridization to detect deletion of these genes may offer a highly sensitive and specific assay to distinguish ChRCC from RO.


Assuntos
Adenoma Oxífilo/genética , Carcinoma de Células Renais/genética , Deleção de Genes , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Renais/genética , Receptor ErbB-4/genética , Proteínas de Ligação a Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética , Adenoma Oxífilo/diagnóstico , Adulto , Idoso , Carcinoma de Células Renais/diagnóstico , Diagnóstico Diferencial , Feminino , Genes Supressores de Tumor , Humanos , Neoplasias Renais/diagnóstico , Masculino , Pessoa de Meia-Idade , Oncogenes
6.
Am J Hematol ; 94(2): 209-215, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30417942

RESUMO

An intensive "5 + 1" regimen, which included bolus high dose cytarabine (HiDAC) at 3 g/m2 once daily over 3 hours on days 1-5 and high dose mitoxantrone (HDM) 80 mg/m2 on day 2, was evaluated in 101 consecutively treated newly diagnosed acute myeloid leukemia (AML) patients at a single center since 2009. The median age was 65 (range 18-90) years. The 4 and 8-week mortality in our cohort was 3/101 (2.9%) and 7/99 (7%), respectively. The overall response (complete remission [CR] + CRi) was 76.2% (77/101). The median overall survival (OS) stratified by age group <60, 60-69 and ≥70 years were 56, 31 and 9 months respectively (log-rank, P = 0.02). 51.7% (45/84) of patients with intermediate/adverse risk category proceeded to allogeneic stem cell transplants. Among these 84 patients, the percentage of patients able to proceed to transplant in age groups <60, 60-69, and ≥ 70 years were 75% (18/24), 60.7% (17/28), and 31.2% (10/32), respectively. In conclusion, HDM-based chemotherapy regimen produces high CR rates, is well tolerated and more patients can undergo curative postremission therapy including stem cell transplant.


Assuntos
Quimioterapia de Indução/métodos , Leucemia Mieloide Aguda/tratamento farmacológico , Mitoxantrona/administração & dosagem , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Transplante de Células-Tronco , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
7.
Proc Natl Acad Sci U S A ; 113(52): 15024-15029, 2016 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-27956626

RESUMO

The p53 tumor suppressor acts as a guardian of the genome by preventing the propagation of DNA damage-induced breaks and mutations to subsequent generations of cells. We have previously shown that phosphorylation of the Mdm2 oncoprotein at Ser394 by the ATM kinase is required for robust p53 stabilization and activation in cells treated with ionizing radiation, and that loss of Mdm2 Ser394 phosphorylation leads to spontaneous tumorigenesis and radioresistance in Mdm2S394A mice. Previous in vitro data indicate that the c-Abl kinase phosphorylates Mdm2 at the neighboring residue (Tyr393) in response to DNA damage to regulate p53-dependent apoptosis. In this present study, we have generated an Mdm2 mutant mouse (Mdm2Y393F) to determine whether c-Abl phosphorylation of Mdm2 regulates the p53-mediated DNA damage response or p53 tumor suppression in vivo. The Mdm2Y393F mice develop accelerated spontaneous and oncogene-induced tumors, yet display no defects in p53 stabilization and activity following acute genotoxic stress. Although apoptosis is unaltered in these mice, they recover more rapidly from radiation-induced bone marrow ablation and are more resistant to whole-body radiation-induced lethality. These data reveal an in vivo role for c-Abl phosphorylation of Mdm2 in regulation of p53 tumor suppression and bone marrow failure. However, c-Abl phosphorylation of Mdm2 Tyr393 appears to play a lesser role in governing Mdm2-p53 signaling than ATM phosphorylation of Mdm2 Ser394. Furthermore, the effects of these phosphorylation events on p53 regulation are not additive, as Mdm2Y393F/S394A mice and Mdm2S394A mice display similar phenotypes.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-abl/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/química , Tolerância a Radiação , Proteína Supressora de Tumor p53/metabolismo , Alelos , Animais , Apoptose , Dano ao DNA , Éxons , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/genética , Neoplasias/radioterapia , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais
8.
Histopathology ; 69(6): 1055-1065, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27458708

RESUMO

AIMS: Genes affecting epigenetic pathways are frequently mutated in myeloid malignancies, including acute myeloid leukaemia (AML). The genes encoding TET2, IDH1 and IDH2 are among the most commonly mutated genes, and cause defective conversion of 5-methylcytosine into 5-hydroxymethylcytosine (5hmC), impairing demethylation of DNA, and presumably serving as driver mutations in leukaemogenesis. The aim of this study was to correlate 5hmC immunohistochemical loss with the mutation status of genes involved in epigenetic pathways in AML. METHODS AND RESULTS: Immunohistochemical staining with an anti-5hmC antibody was performed on 41 decalcified, formalin-fixed paraffin-embedded (FFPE) bone marrow biopsies from patients with AML. Archived DNA was subjected to next-generation sequencing for analysis of a panel of genes, including TET2, IDH1, IDH2, WT1 and DNMT3A. TET2, IDH1, IDH2, WT1 and DNMT3A mutations were found in 46% (19/41) of the cases. Ten of 15 cases (67%) with TET2, IDH1, IDH2 or WT1 mutations showed deficient 5hmC staining, whereas nine of 26 cases (35%) without a mutation in these genes showed loss of 5hmC. It is of note that all four cases with TET2 mutations showed deficient 5hmC staining. CONCLUSIONS: Overall, somatic mutations in TET2, IDH1, IDH2, WT1 and DNMT3A were common in our cohort of AML cases. Immunohistochemical staining for 5hmC was lost in the majority of cases harbouring mutations in these genes, reflecting the proposed relationship between dysfunctional epigenetic pathways and leukaemogenesis.


Assuntos
5-Metilcitosina/análogos & derivados , Leucemia Mieloide Aguda/genética , 5-Metilcitosina/análise , 5-Metilcitosina/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Análise Mutacional de DNA , Epigênese Genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , História do Século XVII , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação
9.
Hemoglobin ; 40(3): 208-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27117572

RESUMO

We report an infant with a compound heterozygosity for Hb C (HBB: c.19G > A) and Hb Osu Christiansborg (HBB: c.157G > A) and a phenotype of mild microcytic anemia with target cell morphology but without overt hemolysis.


Assuntos
Anemia Hipocrômica/genética , Hemoglobina C/genética , Hemoglobinas Anormais/genética , Heterozigoto , Humanos , Lactente , Fenótipo
10.
Mod Pathol ; 27(7): 936-44, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24390216

RESUMO

DNA methylation is the most well-studied epigenetic modification in cancer biology. 5-hydroxymethylcytosine is an epigenetic mark that can be converted from 5-methylcytosine by the ten-eleven translocation gene family. We recently reported the loss of 5-hydroxymethylcytosine in melanoma compared with benign nevi and suggested that loss of this epigenetic marker is correlated with tumor virulence based on its association with a worse prognosis. In this study, we further characterize the immunoreactivity patterns of 5-hydroxymethylcytosine in the full spectrum of melanocytic lesions to further validate the potential practical application of this epigenetic marker. One hundred and seventy-five cases were evaluated: 18 benign nevi, 20 dysplastic nevi (10 low-grade and 10 high-grade lesions), 10 atypical Spitz nevi, 20 borderline tumors, 5 melanomas arising within nevi, and 102 primary melanomas. Progressive loss of 5-hydroxymethylcytosine from benign dermal nevi to high-grade dysplastic nevi to borderline melanocytic neoplasms to melanoma was observed. In addition, an analysis of the relationship of nuclear diameter with 5-hydroxymethylcytosine staining intensity within lesional cells revealed a significant correlation between larger nuclear diameter and decreased levels of 5-hydroxymethylcytosine. Furthermore, borderline lesions uniquely exhibited a diverse spectrum of staining of each individual case. This study further substantiates the association of 5-hydroxymethylcytosine loss with dysplastic cytomorphologic features and tumor progression and supports the classification of borderline lesions as a biologically distinct category of melanocytic lesions.


Assuntos
Citosina/análogos & derivados , Melanoma/genética , Nevo/genética , Lesões Pré-Cancerosas/genética , Neoplasias Cutâneas/genética , 5-Metilcitosina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Metilação de DNA , Feminino , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Nevo/patologia , Lesões Pré-Cancerosas/patologia , Neoplasias Cutâneas/patologia , Adulto Jovem
11.
Adv Anat Pathol ; 21(3): 191-200, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24713990

RESUMO

IMP3 is a member of a family of RNA-binding proteins that consists of IMP1, IMP2 and IMP3. These proteins contain 2 RNA recognition motifs and 4 K-homology domains that allow them to bind RNAs strongly and specifically. IMP3 is an oncofetal protein involved in embryogenesis and its expression is associated with a number of malignant neoplasms. IMP3 is associated with aggressive and advanced cancers and is specifically expressed in malignant tumors but is not found in adjacent benign tissues. Moreover, in vitro studies have shown that IMP3 promotes tumor cell proliferation, adhesion, and invasion. This review focuses on the studies of IMP3 expression in different cancers and emphasizes the potential utility of IMP3 in routine surgical pathology practice. We also discuss IMP3 as a prognostic biomarker for cancer patients' outcomes.


Assuntos
Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias/genética , Neoplasias/patologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Progressão da Doença , Humanos , Valor Preditivo dos Testes , Prognóstico
12.
J Hematol ; 13(3): 86-93, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38993741

RESUMO

Background: Allogeneic stem cell transplant (allo-SCT) is a mainstay of treatment for acute myeloid leukemia (AML). Its success depends largely on response of donor T lymphocytes against leukemia cells, known as graft-vs-leukemia (GvL) effect. A key potential driver of GvL is immune response to mutation-derived neoantigens. Previous studies in solid tumors have demonstrated enhanced immunogenicity of frameshift (FS)-derived peptides vs. those from non-synonymous single nucleotide variants (SNVs). We therefore hypothesized that AML cases bearing FS mutations in leukemia-associated genes would be more immunogenic than those with only other types of mutations (non-FS), and thus benefit more from allo-SCT via more robust GvL. Methods: We identified AML patients who had undergone allo-SCT between 2010 and 2022 and had next-generation sequencing data available on diagnostic specimens using a 42-gene hot spot panel. We compared the impact of tumor mutations present at diagnosis on overall survival and relapse-free survival based on FS versus non-FS status. Results: Ninety-five AML allo-SCT patients were identified. We observed superior relapse-free survival (P = 0.038, hazard ratio (HR): 0.24) and borderline superior overall survival (P = 0.058, HR: 0.55) post-transplant in de novo AML patients, who had at least one FS mutation (other than NPM1) in one of the 42 assessed genes versus those with only non-FS mutations. Conclusions: Our findings suggest that FS-mutated AML cases may benefit more from allo-SCT than those with only non-FS mutations, possibly due to increased generation of immunogenic neoepitopes. If validated in an expanded study, incorporation of somatic FS mutation status in AML could improve patient selection algorithms for bone marrow transplant and thereby lead to superior outcomes.

13.
Br J Haematol ; 161(5): 609-622, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23577835

RESUMO

Haemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory disorder resulting from immune dysfunction reflecting either primary immune deficiency or acquired failure of normal immune homeostasis. Familial HLH includes autosomal recessive and X-linked disorders characterized by uncontrolled activation of T cells and macrophages and overproduction of inflammatory cytokines, secondary to defects in genes encoding proteins involved in granule-dependent cytolytic pathways. In older children and adults, HLH is associated more often with infections, malignancies, autoimmune diseases, and acquired immune deficiencies. HLH, macrophage activation syndrome, sepsis, and systemic inflammatory response syndrome are different clinical entities that probably represent a common immunopathological state, termed cytokine storm. These conditions may be clinically indistinguishable; all include massive inflammatory response, elevated serum cytokine levels, multi-organ involvement, haemophagocytic macrophages, and often death. Tissues of haematopoietic and lymphoid function are directly involved; other organs are secondarily damaged by circulating cytokines and chemokines. Haemophagocytic disorders are now increasingly diagnosed in the context of severe inflammatory reactions to viruses, malignancies and systemic connective tissue diseases. Many of these cases may reflect underlying genetic predispositions to HLH. The detection of gene defects has contributed considerably to our understanding of HLH, but the mechanisms leading to acquired HLH have yet to be fully determined.


Assuntos
Linfo-Histiocitose Hemofagocítica/etiologia , Infecções por Vírus Epstein-Barr/complicações , Predisposição Genética para Doença , Humanos , Síndromes de Imunodeficiência/complicações , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/genética , Síndrome de Ativação Macrofágica/etiologia , Mutação , Neoplasias/complicações
14.
EJHaem ; 4(4): 1059-1070, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38024632

RESUMO

TP53 aberrations constitute the highest risk subset of myelodysplastic neoplasms (MDS) and acute myeloid leukemia (AML). The International Consensus Classification questions the blast threshold between MDS and AML. In this study, we assess the distinction between MDS and AML for 76 patients with TP53 aberrations. We observed no significant differences between MDS and AML regarding TP53 genomics. Median overall survival (OS) was 223 days for the entire group, but prognostic discrimination within subgroups showed the most inferior OS (46 days) for AML with multihit allelic state plus TP53 variant allele frequency (VAF) > 50%. In multivariate analysis, unadjusted Cox models revealed the following variables as independent risk factors for mortality: AML (vs. MDS) (hazard ratio [HR]: 2.50, confidence interval [CI]: 1.4-4.4, p = 0.001), complex karyotype (HR: 3.00, CI: 1.4-6.1, p = 0.003), multihit status (HR: 2.30, CI 1.3-4.2, p = 0.005), and absence of hematopoietic cell transplant (HCT) (HR: 3.90, CI: 1.8-8.9, p = 0.0009). Clonal dynamic modeling showed a significant reduction in TP53 VAF with front-line hypomethylating agents. These findings clarify the impact of specific covariates on outcomes of TP53-aberrant myeloid neoplasms, irrespective of the diagnosis of MDS versus AML, and may influence HCT decisions.

15.
Curr Treat Options Oncol ; 13(1): 122-36, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22241590

RESUMO

OPINION STATEMENT: Post transplant lymphoproliferative disorder (PTLD) is a heterogeneous disease that may occur in recipients of solid organ transplants (SOT) and hematopoietic stem cell transplant. The risk of lymphoma is increased 20-120% compared with the general population with risk dependent in part on level of immune suppression. In addition, recent data have emerged, including HLA and cytokine gene polymorphisms, regarding genetic susceptibility to PTLD. Based on morphologic, immunophenotypic, and molecular criteria, PLTD are classified into 4 pathologic categories: early lesions, polymorphic, monomorphic, and classical Hodgkin lymphoma. Evaluation by expert hematopathology is critical in establishing the diagnosis. The aim of therapy for most patients is cure with the concurrent goal of preservation of allograft function. Given the pathologic and clinical heterogeneity of PTLD, treatment is often individualized. A mainstay of therapy remains reduction of immune suppression (RI) with the level of reduction being dependent on several factors (e.g., history of rejection, current dosing, and type of allograft). Outside of early lesions and/or low tumor burden, however, RI alone is associated with cure in a minority of subjects. We approach most newly-diagnosed polymorphic and monomorphic PTLDs similarly using frontline single-agent rituximab (4 weeks followed by abbreviated maintenance) in conjunction with RI. Frontline combination chemotherapy may be warranted for patients with high tumor burden in need of prompt response or following failure of RI and/or rituximab. Due to chemotherapy-related complications in PTLD, especially infectious, we advocate comprehensive supportive care measures. Surgery or radiation may be considered for select patients with early-stage disease. For PTLD subjects with primary CNS lymphoma, we utilize therapeutic paradigms similar to immunocompetent CNS lymphoma using high-dose methotrexate-based therapy with concurrent rituximab therapy and sequential high-dose cytarabine. Finally, novel therapeutic strategies, especially adoptive immunotherapy, should continued to be explored.


Assuntos
Anticorpos Monoclonais Murinos/administração & dosagem , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Terapia de Imunossupressão/efeitos adversos , Imunoterapia Adotiva/métodos , Linfoma/tratamento farmacológico , Transtornos Linfoproliferativos/tratamento farmacológico , Transplante de Órgãos/efeitos adversos , Linfócitos T/efeitos dos fármacos , Infecções por Vírus Epstein-Barr/epidemiologia , Feminino , Humanos , Linfoma/epidemiologia , Transtornos Linfoproliferativos/classificação , Transtornos Linfoproliferativos/epidemiologia , Transtornos Linfoproliferativos/imunologia , Masculino , Fatores de Risco , Rituximab
16.
Pediatr Blood Cancer ; 56(5): 856-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21370424

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is a rare histiocytic reactive process due to mutations in the perforin, MUNC13-4 or syntaxin 11 genes, or secondary to malignancy, infection or autoimmune disorder. HLH as a preceding diagnosis to leukemia is rare. We report two cases with progression to acute leukemia, one heterozygous for MUNC13-4 and the other with reduced natural killer (NK) cell function and perforin expression. These defects may predispose to a secondary HLH-like presentation of pre-clinical leukemia or confer increased susceptibility to malignancy. HLH patients with genetic mutations or NK cell function abnormalities need monitoring for future malignancy even if the HLH resolves.


Assuntos
Células Matadoras Naturais/patologia , Leucemia Monocítica Aguda/etiologia , Linfo-Histiocitose Hemofagocítica/genética , Proteínas de Membrana/genética , Mutação/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Pré-Escolar , Feminino , Heterozigoto , Humanos , Leucemia Monocítica Aguda/patologia , Perforina/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Proteínas Qa-SNARE/genética
17.
Leuk Res Rep ; 13: 100190, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31867207

RESUMO

Mucous membrane plasmacytosis (MMP) is an uncommon variant of mucositis represented by a polyclonal plasma cell infiltration of mucosal tissue. Various clinical presentations in the upper airway have been reported ranging from erythematous mucosa to fungating masses. Histologic features include mucosal epithelial hyperplasia or psoriasiform changes with a dense submucosal infiltrate of polytypic plasma cells. Molecular studies for immunoglobulin gene rearrangement should be performed in all cases of MMP to rule out clonal neoplastic expansion of plasma cells. We present a case of MMP with over 15 years of clinical follow-up, emphasizing the relatively benign clinical course of this disorder.

18.
Mod Pathol ; 22(7): 977-84, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19407852

RESUMO

The diagnosis of gastric epithelial dysplasia, a precursor lesion of gastric adenocarcinoma, is hindered by interobserver variability and by its resemblance to regenerative changes. Loss of cell polarity, a histological feature of gastric epithelial dysplasia, may be difficult to ascertain, especially in the setting of inflammation or injury. A biomarker of cell polarity could be useful in diagnosis of dysplasia, but has not been reported. The Lethal giant larvae (lgl) gene controls apical-basal polarity of epithelial cells in Drosophila, and has properties of a tumor-suppressor gene. Two homologs, lgl1 and lgl2, are present in mammals and lgl2 mRNA is highly expressed in the stomach. The goal of our study was to test the hypothesis that Lgl2 protein expression and/or localization are disrupted in gastric epithelial dysplasia and adenocarcinoma. Routinely processed pathology specimens including 94 benign mucosae of digestive organs, in addition to 36 reactive gastropathy, 57 gastric epithelial dysplasia, and 77 gastric adenocarcinomas, were immunostained for Lgl2 protein. All normal, reactive, and chronically inflamed gastric epithelia showed basolateral Lgl2 staining. Normal esophageal, duodenal, colonic, biliary, and pancreatic duct mucosae, as well as gastric intestinal metaplasia, did not express Lgl2. All but one case each of gastric epithelial dysplasia and adenocarcinoma showed either complete loss of anti-Lgl2 immunoreactivity or diffuse, mostly weak, cytoplasmic staining. Complete loss of immunoreactivity was significantly more often observed in diffuse-type than in intestinal-type adenocarcinomas (79 vs 48%, respectively). Our data suggest that Lgl2 expression is either aberrantly localized or lost in gastric epithelial dysplasia and adenocarcinoma, whereas it is maintained in reactive gastric mucosa. We propose that Lgl2 may be a potential marker to rule out gastric epithelial dysplasia and adenocarcinoma in diagnostic specimens. However, the consistently negative anti-Lgl2 immunoreactivity seen in intestinal metaplasia does not allow differentiation of dysplasia from intestinal metaplasia with reactive change.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Proteínas do Citoesqueleto/metabolismo , Mucosa Gástrica/metabolismo , Lesões Pré-Cancerosas/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/patologia , Adenoma/metabolismo , Adenoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Polaridade Celular , Feminino , Técnica Direta de Fluorescência para Anticorpo , Mucosa Gástrica/patologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologia , Neoplasias Gástricas/patologia , Adulto Jovem
19.
Haematologica ; 94(1): 29-37, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19001281

RESUMO

BACKGROUND: The presence of paroxysmal nocturnal hemoglobinuria clones in the setting of aplastic anemia or myelodysplastic syndrome has been shown to have prognostic and therapeutic implications. However, the status of paroxysmal nocturnal hemoglobinuria clones in various categories of myelodysplastic syndrome and in other bone marrow disorders is not well-studied. DESIGN AND METHODS: By using multiparameter flow cytometry immunophenotypic analysis with antibodies specific for four glycosylphosphatidylinositol-anchored proteins (CD55, CD59, CD16, CD66b) and performing an aerolysin lysis confirmatory test in representative cases, we assessed the paroxysmal nocturnal hemoglobinuria-phenotype granulocytes in 110 patients with myelodysplastic syndrome, 15 with myelodysplastic/myeloproliferative disease, 5 with idiopathic myelofibrosis and 6 with acute myeloid leukemia. RESULTS: Paroxysmal nocturnal hemoglobinuria-phenotype granulocytes were detected in nine patients with low grade myelodysplastic syndrome who showed clinicopathological features of bone marrow failure, similar to aplastic anemia. All paroxysmal nocturnal hemoglobinuria-positive cases demonstrated loss of the four glycosylphosphatidylinositol-anchored proteins, with CD16(-)CD66b(-) clones being larger than those of CD55(-)CD59(-) (p<0.05). Altered glycosylphosphatidylinositol-anchored protein expression secondary to granulocytic hypogranulation, immaturity, and/or immunophenotypic abnormalities was present in a substantial number of cases and diagnostically challenging. CONCLUSIONS: These results show that routine screening for paroxysmal nocturnal hemoglobinuria clones in patients with an intrinsic bone marrow disease who show no clinical evidence of hemolysis has an appreciable yield in patients with low grade myelodysplastic syndromes. The recognition of diagnostic caveats and pitfalls associated with the underlying intrinsic bone marrow disease is essential in interpreting paroxysmal nocturnal hemoglobinuria testing correctly. In our experience, the CD16/CD66b antibody combination is superior to CD55/CD59 in screening for subclinical paroxysmal nocturnal hemoglobinuria because it detects a large clone size and is less subject to analytical interference.


Assuntos
Doenças da Medula Óssea/complicações , Doenças da Medula Óssea/diagnóstico , Hemoglobinúria Paroxística/complicações , Hemoglobinúria Paroxística/diagnóstico , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças da Medula Óssea/sangue , Doenças da Medula Óssea/classificação , Antígenos CD55/metabolismo , Antígenos CD59/metabolismo , Diferenciação Celular , Feminino , Hemoglobinúria Paroxística/sangue , Hemoglobinúria Paroxística/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/classificação , Fenótipo
20.
Clin Cancer Res ; 14(6): 1701-6, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18347170

RESUMO

PURPOSE: In this study, we investigated whether an oncofetal protein, IMP3, can serve as a new biomarker to predict progression and metastasis of early-stage urothelial carcinoma of the bladder. EXPERIMENTAL DESIGN: The expression of IMP3 in 242 patients with primary superficial bladder urothelial carcinoma and metastatic urothelial carcinoma was evaluated by immunohistochemistry. Patients with primary superficial urothelial carcinoma of the bladder were further investigated by use of survival analysis. RESULTS: Twenty percent (42 of 214) of primary superficial urothelial carcinomas and 93% (26 of 28) of metastatic urothelial carcinomas expressed IMP3. Kaplan-Meier plots and log-rank tests showed that patients with IMP3-positive tumors had a much lower progression-free survival (P = 0.0002) and disease-free survival rate (P = 0.0067) than did those with IMP3-negative tumors. The 5-year progression-free and disease-free survival rates were 91% and 94% in IMP3-negative patients versus 64% and 76% in IMP3-positive patients, respectively. Sixty percent of IMP3-positive patients with superficial invasive urothelial carcinoma at initial diagnosis went on to develop metastases, whereas no metastasis was found in IMP3-negative patients (P = 0.0017). In the multivariable Cox analysis, patients with IMP3 expression in their superficial urothelial carcinomas subsequently developed invasive tumors or metastasis at a rate that was about five times greater than cases without expression of IMP3 adjusting for other well-known clinical variables (tumor stage and grade, etc.). CONCLUSIONS: Our findings indicate that IMP3 is an independent prognostic marker that can identify a group of patients with a high potential to develop progression and who might benefit from early aggressive therapy.


Assuntos
Carcinoma Papilar/diagnóstico , Carcinoma Papilar/patologia , Proteínas de Neoplasias/metabolismo , Proteínas de Ligação a RNA/metabolismo , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma Papilar/metabolismo , Carcinoma Papilar/mortalidade , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Neoplasias/fisiologia , Prognóstico , Proteínas de Ligação a RNA/fisiologia , Análise de Sobrevida , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/mortalidade , Urotélio/metabolismo , Urotélio/patologia
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