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1.
Mol Cell ; 82(10): 1940-1955.e7, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35447080

RESUMO

Previously, we showed that CDYL1 is recruited to DNA double-strand breaks (DSBs) to promote homologous recombination (HR) repair and foster transcriptional silencing. However, how CDYL1 elicits DSB-induced silencing is not fully understood. Here, we identify a CDYL1-dependent local decrease in the transcriptionally active marks histone lysine crotonylation (Kcr) and crotonylated lysine 9 of H3 (H3K9cr) at AsiSI-induced DSBs, which correlates with transcriptional silencing. Mechanistically, we reveal that CDYL1 crotonyl-CoA hydratase activity counteracts Kcr and H3K9cr at DSB sites, which triggers the eviction of the transcription elongation factor ENL and fosters transcriptional silencing. Furthermore, genetic inhibition of CDYL1 hydratase activity blocks the reduction in H3K9cr and alleviates DSB-induced silencing, whereas HR efficiency unexpectedly remains intact. Therefore, our results functionally uncouple the repair and silencing activity of CDYL1 at DSBs. In a broader context, we address a long-standing question concerning the functional relationship between HR repair and DSB-induced silencing, suggesting that they may occur independently.


Assuntos
Quebras de DNA de Cadeia Dupla , Lisina , DNA , Reparo do DNA por Junção de Extremidades , Reparo do DNA , Histonas/genética , Histonas/metabolismo , Lisina/genética
2.
Mol Cell ; 82(21): 4080-4098.e12, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36272410

RESUMO

Growing evidence suggests prevalence of transcriptional condensates on chromatin, yet their mechanisms of formation and functional significance remain largely unclear. In human cancer, a series of mutations in the histone acetylation reader ENL create gain-of-function mutants with increased transcriptional activation ability. Here, we show that these mutations, clustered in ENL's structured acetyl-reading YEATS domain, trigger aberrant condensates at native genomic targets through multivalent homotypic and heterotypic interactions. Mechanistically, mutation-induced structural changes in the YEATS domain, ENL's two disordered regions of opposing charges, and the incorporation of extrinsic elongation factors are all required for ENL condensate formation. Extensive mutagenesis establishes condensate formation as a driver of oncogenic gene activation. Furthermore, expression of ENL mutants beyond the endogenous level leads to non-functional condensates. Our findings provide new mechanistic and functional insights into cancer-associated condensates and support condensate dysregulation as an oncogenic mechanism.


Assuntos
Neoplasias , Corpos Nucleares , Humanos , Domínios Proteicos , Cromatina/genética , Mutação , Neoplasias/genética
3.
Biochem Biophys Res Commun ; 596: 36-42, 2022 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-35108652

RESUMO

Both MLL-AF9 and MLL-ENL leukemia fusion proteins drive oncogenic transformation of hematopoietic cells through their N-terminal DNA/histone binding mixed-lineage leukemia 1 domain and C-terminal fragment of AF9 or ENL containing an unstructured linker region and the ANC1 homology domain, which recruits transcription factors. Despite of their structural similarity, acute myeloid leukemia (AML) patients bearing MLL-ENL show more adverse outcomes compared to those with MLL-AF9. We recapitulated the clinical patterns of these two MLL-fusions driven AMLs using murine models and found that MLL-ENL AML cells showed slower cell cycle progression and more resistance to standard chemotherapy than MLL-AF9 cells. These phenotypes were primarily controlled by the linker regions of ENL and a highly conserved lysine residue K469 within. Substitution of K469 with an acetylated mimic glutamine abolished the ability of MLL-ENL to suppress proliferation and promote chemo-resistance. We showed that deacetylase Sirt2 might act as an upstream regulator of MLL-ENL. Deletion of Sirt2 promoted proliferation of AML cells with either MLL fusions. Importantly, loss of Sirt2 greatly enhanced the sensitivity of the MLL-ENL AML cells to chemo-treatment. Taken together, our study uncovered a unique regulatory role of Sirt2 in leukemogenesis and suggested targeting SIRT2 as a new way to sensitize MLL-ENL AML patience for chemotherapy.


Assuntos
Proliferação de Células/genética , Regulação Leucêmica da Expressão Gênica/genética , Leucemia Mieloide/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Sirtuína 2/genética , Doença Aguda , Sequência de Aminoácidos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Citarabina/administração & dosagem , Doxorrubicina/administração & dosagem , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Estimativa de Kaplan-Meier , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína de Leucina Linfoide-Mieloide/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Homologia de Sequência de Aminoácidos , Sirtuína 2/metabolismo , Células Tumorais Cultivadas
4.
Semin Immunol ; 39: 111-118, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29950273

RESUMO

Leprosy is still a considerable health threat in pockets of several low and middle income countries worldwide where intense transmission is witnessed, and often results in irreversible disabilities and deformities due to delayed- or misdiagnosis. Early detection of leprosy represents a substantial hurdle in present-day leprosy health care. The dearth of timely diagnosis has, however, particularly severe consequences in the case of inflammatory episodes, designated leprosy reactions, which represent the major cause of leprosy-associated irreversible neuropathy. There is currently no accurate, routine diagnostic test to reliably detect leprosy reactions, or to predict which patients will develop these immunological exacerbations. Identification of host biomarkers for leprosy reactions, particularly if correlating with early onset prior to development of clinical symptoms, will allow timely interventions that contribute to decreased morbidity. Development of a point-of-care (POC) test based on such correlates would be a definite game changer in leprosy health care. In this review, proteomic-, transcriptomic and metabolomic research strategies aiming at identification of host biomarker-based correlates of leprosy reactions are discussed, next to external factors associated with occurrence of these episodes. The vast diversity in research strategies combined with the variability in patient- and control cohorts argues for harmonisation of biomarker discovery studies with geographically overarching study sites. This will improve identification of specific correlates associated with risk of these damaging inflammatory episodes in leprosy and subsequent application to rapid field tests.


Assuntos
Anticorpos Antibacterianos/análise , Determinação de Ponto Final/métodos , Hanseníase/diagnóstico , Mycobacterium leprae/imunologia , Transcriptoma/imunologia , Anticorpos Antibacterianos/biossíntese , Biomarcadores/metabolismo , Ligante CD30/genética , Ligante CD30/imunologia , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/imunologia , Diagnóstico Tardio , Progressão da Doença , Humanos , Hanseníase/imunologia , Hanseníase/microbiologia , Hanseníase/patologia , Metaboloma/imunologia , Mycobacterium leprae/isolamento & purificação , Mycobacterium leprae/patogenicidade , Testes Imediatos , Biologia de Sistemas/métodos , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia
5.
Dermatol Ther ; 34(6): e15125, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34490707

RESUMO

Management of chronic/recurrent erythema nodosum leprosum (ENL) is challenging. The majority of these patients become steroid-dependent and suffer from the adverse effects of long-term corticosteroid use. Minocycline has shown promising results in a small series of chronic/recurrent ENL patients. The aim of this study was to compare the efficacy and safety of minocycline and clofazimine in patients with chronic/recurrent ENL. In this prospective randomized clinical trial, 60 participants with chronic/recurrent ENL were randomized (1:1) to receive either minocycline 100 mg once daily or clofazimine 100 mg thrice daily for 12 weeks along with prednisolone according to WHO protocol and followed up for 6 months. The outcome measures were mean time for initial control of ENL, proportion of patients having a recurrence of ENL, mean time for recurrence after initial control, additional prednisolone requirement, and frequency of adverse events. Initial control of ENL was achieved earlier in the minocycline group as compared to the clofazimine group (2.97 ± 1.9 weeks vs. 4 ± 1.96 weeks, respectively; p-0.048). The number of participants having ENL flares/recurrences during the study period was comparable in both groups (71.4% in clofazimine vs. 55.2% in minocycline group; p-0.2). The participants in the minocycline group remained in remission for a longer duration after initial control of ENL as compared to the clofazimine group (p-0.001). Mean additional prednisolone dose required for control of ENL flares/recurrences was also comparable in both groups (p-0.09). The minocycline group had fewer side effects than the clofazimine group (p-0.047). Minocycline led to a rapid and sustained improvement of ENL episodes with fewer adverse events showing a superior efficacy to clofazimine.


Assuntos
Eritema Nodoso , Hanseníase Virchowiana , Clofazimina/efeitos adversos , Eritema Nodoso/diagnóstico , Eritema Nodoso/tratamento farmacológico , Humanos , Hansenostáticos/efeitos adversos , Hanseníase Virchowiana/diagnóstico , Hanseníase Virchowiana/tratamento farmacológico , Minociclina/efeitos adversos , Estudos Prospectivos
6.
Adv Exp Med Biol ; 1330: 55-73, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34339030

RESUMO

Ovarian cancer, one of the three leading malignancies in women, has high incidence and mortality worldwide. It is hard to diagnose until very late stages and the 5-year survival rate is very low, due mostly to its distant metastasis. Chemotherapy is currently the most common treatment to inhibit cancer growth, but long-term use could result in resistance and tumor recurrence in addition to damages to normal tissues and functions of the patients. In order to achieve safe and curative effects against cancers, many investigators have focused their attention on traditional Chinese herbal medicines. Paclitaxel, a natural antitumor agent, has significant effects on advanced malignancies including ovarian cancer and is in the standard front-line treatment. Additional natural anticancer substances have continually been discovered for their high effectiveness and low side-effects in ovarian cancer prevention and therapy. In this chapter, we summarize recent work on a selected group of natural components, including lignans, ellagic acid, luteolin, mangiferin, and Acanthopanax senticosus, which have all been demonstrated to reduce the progress of epithelial ovarian cancer in a dose-depend manner, by both in vitro and in vivo experiments. The mechanisms of the anticancer activities by these natural components involve expression suppression of MMP2 and MMP9.


Assuntos
Antineoplásicos , Lignanas , Neoplasias Ovarianas , Antineoplásicos/uso terapêutico , Carcinoma Epitelial do Ovário , Feminino , Humanos , Lignanas/farmacologia , Lignanas/uso terapêutico , Recidiva Local de Neoplasia , Neoplasias Ovarianas/tratamento farmacológico
7.
J Pak Med Assoc ; 71(3): 838-842, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34057932

RESUMO

OBJECTIVE: To determine the occurrence and characteristics of the two types of lepra reactions in new leprosy cases at initial diagnosis. METHODS: The retrospective descriptive study was conducted at the Marie Adelaide Leprosy Centre, Karachi, and comprised all new leprosy cases registered from January 1, 2016, to June 30, 2018. Data was collected from the medical record database using a predesigned proforma. RESULTS: Of the 50 cases, 2(4%) were children and 48 (96%) were adults, with overall age ranging from 12 to 85 years. There were 41(82%) males and 9(18%) females.. Of the total, 30(60%) cases presented with type 1 reaction and 20(40%) with type 2. Further, 30(60%) cases were classified as borderline lepromatous. Among them, 17(57%) had type 2 reaction. Inflamed plaques were the main feature in 27(90%) cases of type 1. Crops of painful, erythematous nodules were seen in 19(95%) cases of type 2. CONCLUSION: Lepra reactions were found to be a presenting feature in a significant number of new leprosy cases at initial diagnosis.


Assuntos
Hanseníase , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Etnicidade , Feminino , Humanos , Hanseníase/diagnóstico , Hanseníase/epidemiologia , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Estudos Retrospectivos , Adulto Jovem
8.
J Pak Med Assoc ; 71(10): 2317-2320, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34974562

RESUMO

OBJECTIVE: To determine the occurrence and characteristics of lepra reactions in leprosy patients. METHODS: The retrospective study was conducted at the Marie Adelaide Leprosy Centre, Karachi, and comprised data of patients admitted between January 1, 2013, and December 31, 2015, for the management of lepra reactions. Data was noted on a detailed proforma and was analysed using Microsoft Excel and applying chi-square test. RESULTS: Of the 130 cases, 95(73%) were males and 35(27%) were females. Mean age at onset of the first episode was 39±14 years. Borderline lepromatous was the most common classification 76(58%), with 40(53%) of them having type 1 reaction as the first episode and 36(47%) having a type 2 reaction Risk factors associated with recurrence were skin lesions, fever, lymphadenopathy and type of reaction (p<0.05). CONCLUSION: Healthcare providers need to be aware of the clinical manifestations of lepra reactions in order to diagnose them early.


Assuntos
Hanseníase , Linfadenopatia , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Estudos Retrospectivos
9.
Breast Cancer Res Treat ; 173(3): 545-557, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30367332

RESUMO

PURPOSE: Exposure to the polyphenolic plant lignan secoisolariciresinol diglucoside (SDG) and its metabolite enterolactone (ENL) has been associated with reduced breast cancer progression, particularly for estrogen receptor alpha (ERα)-negative disease, and decreased preclinical mammary tumor growth. However, while preclinical studies have established that SDG and ENL affect measures of progression in models of triple-negative breast cancer (TNBC, a subset of ERα-negative disease), the molecular mechanisms underlying these effects remain unclear. METHODS: C57BL/6 mice were fed a control diet (control, 10% kcal from fat) or control diet + SDG (SDG, 100 mg/kg diet) for 8 weeks, then orthotopically injected with syngeneic E0771 mammary tumor cells (a model of TNBC); tumor growth was monitored for 3 weeks. The role of reduced NF-κB signaling in SDG's anti-tumor effects was explored in vitro via treatment with the bioactive SDG metabolite ENL. In addition to the murine E0771 cells, the in vitro studies utilized MDA-MB-231 and MCF-7 cells, two human cell lines which model the triple-negative and luminal A breast cancer subtypes, respectively. RESULTS: SDG supplementation in the mice significantly reduced tumor volume and expression of phospho-p65 and NF-κB target genes (P < 0.05). Markers of macrophage infiltration were decreased in the distal-to-tumor mammary fat pad of mice supplemented with SDG relative to control mice (P < 0.05). In vitro, ENL treatment inhibited viability, survival, and NF-κB activity and target gene expression in E0771, MDA-MB-231, and MCF-7 cells (P < 0.05). Overexpression of Rela attenuated ENL's inhibition of E0771 cell viability and survival. CONCLUSIONS: SDG reduces tumor growth in the E0771 model of TNBC, likely via a mechanism involving inhibition of NF-κB activity. SDG could serve as a practical and effective adjuvant treatment to reduce recurrence, but greater understanding of its effects is needed to inform the development of more targeted recommendations for its use.


Assuntos
Anti-Inflamatórios/farmacologia , Butileno Glicóis/farmacologia , Linho/química , Glucosídeos/farmacologia , Neoplasias Mamárias Animais/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/sangue , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Biomarcadores , Butileno Glicóis/administração & dosagem , Butileno Glicóis/química , Linhagem Celular Tumoral , Sobrevivência Celular , Citocinas/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Perfilação da Expressão Gênica , Glucosídeos/administração & dosagem , Glucosídeos/química , Imuno-Histoquímica , Lignanas/sangue , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Camundongos
10.
Cell Mol Life Sci ; 75(21): 3931-3941, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30066088

RESUMO

ENL/MLLT1 is a distinctive member of the KMT2 family based on its structural homology. ENL is a histone acetylation reader and a critical component of the super elongation complex. ENL plays pivotal roles in the regulation of chromatin remodelling and gene expression of many important proto-oncogenes, such as Myc, Hox genes, via histone acetylation. Novel insights of the key role of the YEATS domain of ENL in the transcriptional control of leukemogenic gene expression has emerged from whole genome Crisp-cas9 studies in acute myeloid leukemia (AML). In this review, we have summarized what is currently known about the structure and function of the ENL molecule. We described the ENL's role in normal hematopoiesis, and leukemogenesis. We have also outlined the detailed molecular mechanisms underlying the regulation of target gene expression by ENL, as well as its major interacting partners and complexes involved. Finally, we discuss the emerging knowledge of different approaches for the validation of ENL as a therapeutic target and the development of small-molecule inhibitors disrupting the YEATS reader pocket of ENL protein, which holds great promise for the treatment of AML. This review will not only provide a fundamental understanding of the structure and function of ENL and update on the roles of ENL in AML, but also the development of new therapeutic strategies.


Assuntos
Hematopoese/genética , Leucemia Mieloide Aguda/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Acetilação , Montagem e Desmontagem da Cromatina/genética , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Humanos , Leucemia Mieloide Aguda/patologia , Transcrição Gênica
11.
Br J Nutr ; 120(7): 751-762, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30105962

RESUMO

7-Hydroxymatairesinol (7-HMR) is a plant lignan abundant in various concentrations in plant foods. The objective of this study was to test HMRLignan™, a purified form of 7-HMR, and the corresponding Picea abies extract (total extract P. abies; TEP) as dietary supplements on a background of a high-fat diet (HFD)-induced metabolic syndrome in mice and in the 3T3-L1 adipogenesis model. Mice, 3 weeks old, were fed a HFD for 60 d. Subgroups were treated with 3 mg/kg body weight 7-HMR (HMRLignan™) or 10 mg/kg body weight TEP by oral administration. 7-HMR and TEP limited the increase in body weight (-11 and -13 %) and fat mass (-11 and -18 %) in the HFD-fed mice. Epididymal adipocytes were 19 and -12 % smaller and the liver was less steatotic (-62 and -65 %). Serum lipids decreased in TEP-treated mice (-11 % cholesterol, -23 % LDL and -15 % TAG) and sugar metabolism was ameliorated by both lignan preparations, as shown by a more than 70 % decrease in insulin secretion and insulin resistance. The expression of several metabolic genes was modulated by the HFD with an effect that was reversed by lignan. In 3T3-L1 cells, the 7-HMR metabolites enterolactone (ENL) and enterodiol (END) showed a 40 % inhibition of cell differentiation accompanied by the inhibited expression of the adipogenic genes PPARγ, C/EBPα and aP2. Furthermore, END and ENL caused a 10 % reduction in TAG uptake in HEPA 1-6 hepatoma cells. In conclusion, 7-HMR and TEP reduce metabolic imbalances typical of the metabolic syndrome and obesity in male mice, whereas their metabolites inhibit adipogenesis and lipid uptake in vitro.


Assuntos
Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Lignanas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Síndrome Metabólica/tratamento farmacológico , Picea/química , Células 3T3-L1 , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , 4-Butirolactona/uso terapêutico , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Tecido Adiposo/citologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Suplementos Nutricionais , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Expressão Gênica , Resistência à Insulina , Lignanas/uso terapêutico , Lipídeos/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/etiologia , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/sangue , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/prevenção & controle , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
12.
J Infect Dis ; 216(12): 1635-1643, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29272525

RESUMO

Background: Leprosy, the leading infectious cause of disability worldwide, remains a major public health challenge in the most severely affected countries despite the sharp decline in new cases in recent years. The search for biomarkers is essential to achieve a better understanding of the molecular and cellular mechanisms underlying the disease. Methods: Pentraxin-3 (PTX3) analyses of sera from 87 leprosy patients with or without reactions were conducted via enzyme-linked immunosorbent assay. In situ identification of PTX3 in skin lesion was confirmed by quantitative reverse-transcription polymerase chain reaction, immunohistochemistry, and immunofluorescence assays. Results: We found that PTX3 serum levels were higher in multibacillary patients when evaluated before the onset of acute erythema nodosum leprosum (ENL) and persistently elevated during reaction. Thalidomide treatment reduced PTX3 in the serum 7 days after starting treatment. In situ analyses have also demonstrated enhancement of PTX3 in ENL lesions and showed that treatment with thalidomide reduced its expression and the prominent neutrophilic infiltrate, a hallmark of the disease. Conclusions: In summary, our study provides in vivo evidence that PTX3 is enhanced during ENL but not in reversal reaction and provides a new molecular target in ENL pathogenesis.


Assuntos
Biomarcadores/análise , Proteína C-Reativa/análise , Eritema Nodoso/diagnóstico , Eritema Nodoso/patologia , Hanseníase Virchowiana/diagnóstico , Hanseníase Virchowiana/patologia , Componente Amiloide P Sérico/análise , Adolescente , Adulto , Idoso , Proteína C-Reativa/genética , Estudos de Casos e Controles , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Hansenostáticos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Componente Amiloide P Sérico/genética , Pele/patologia , Talidomida/administração & dosagem , Adulto Jovem
13.
J Biol Chem ; 288(42): 30585-30596, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-23996074

RESUMO

The MLL fusion proteins, AF9 and ENL, activate target genes in part via recruitment of the histone methyltransferase DOT1L (disruptor of telomeric silencing 1-like). Here we report biochemical, biophysical, and functional characterization of the interaction between DOT1L and MLL fusion proteins, AF9/ENL. The AF9/ENL-binding site in human DOT1L was mapped, and the interaction site was identified to a 10-amino acid region (DOT1L865-874). This region is highly conserved in DOT1L from a variety of species. Alanine scanning mutagenesis analysis shows that four conserved hydrophobic residues from the identified binding motif are essential for the interactions with AF9/ENL. Binding studies demonstrate that the entire intact C-terminal domain of AF9/ENL is required for optimal interaction with DOT1L. Functional studies show that the mapped AF9/ENL interacting site is essential for immortalization by MLL-AF9, indicating that DOT1L interaction with MLL-AF9 and its recruitment are required for transformation by MLL-AF9. These results strongly suggest that disruption of interaction between DOT1L and AF9/ENL is a promising therapeutic strategy with potentially fewer adverse effects than enzymatic inhibition of DOT1L for MLL fusion protein-associated leukemia.


Assuntos
Transformação Celular Neoplásica/metabolismo , Metiltransferases/metabolismo , Proteína de Leucina Linfoide-Mieloide/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células HEK293 , Histona-Lisina N-Metiltransferase , Humanos , Metiltransferases/química , Metiltransferases/genética , Mutagênese Sítio-Dirigida , Proteína de Leucina Linfoide-Mieloide/química , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteínas de Fusão Oncogênica/química , Proteínas de Fusão Oncogênica/genética , Ligação Proteica , Fatores de Elongação da Transcrição/química , Fatores de Elongação da Transcrição/genética
14.
Iran J Pathol ; 19(2): 250-258, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39118802

RESUMO

Background & Objective: Primary extranodal lymphoma (pENL) is a malignant lymphoid neoplasm that presents with the main bulk of disease at an extranodal site. The incidence of primary pENL has risen sharply in recent years due to the advent of better diagnostic modalities. Diagnosing pENL can be challenging due to its morphological overlap with other tumors native to the site of origin. This study aims to establish the anatomic distribution, clinical presentations, possible etiologic correlations, and histological subtypes of pENL in a tertiary care center located in South India. Methods: This is a retrospective study of 109 patients with pENL (69 males, 40 females, M: F = 1.7:1) over 5 years (October 2012 to September 2017). The tumors were reclassified according to WHO classification of Haematolymphoid tumors, 5th edition, 2022. Results: pENL constituted 109/481 cases (22.6%) of all NHL cases, with the highest incidence in 7th decade. The gastrointestinal tract (39%) was the predominant site involved, followed by head and neck (26%). Diffuse large B cell lymphoma (DLBCL) was the most common histomorphological variant followed by Follicular lymphoma (FL). The majority of the patients were immunocompetent (89%) and presented with stage IV disease (31.1%) at diagnosis. Conclusion: This study presents an overview of the diverse distribution patterns of both common and rare pENL within a tertiary care center. The accurate diagnosis of pENL necessitates the elimination of secondary extranodal involvement. It is important to note that the accurate diagnosis of pENL requires careful evaluation and exclusion of other possible causes.

15.
Front Immunol ; 15: 1368460, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39072336

RESUMO

Background: Leprosy reactions represent immunologically mediated episodes of acute inflammation that, if not diagnosed and treated promptly, can cause irreversible impairment of nerve function and permanent disabilities. A frequent type of reaction experienced by patients with lepromatous leprosy (LL) and borderline lepromatous leprosy (BL) is erythema nodosum leprosum (ENL), an inflammatory complication that may become chronic or recur in multiple episodes. Although ENL is commonly described as a neutrophil-mediated immune disease, the role of neutrophils is not fully understood. In this study, we assess neutrophilic leukocytosis in a retrospective cohort of patients affected by BL or LL leprosy. Materials and methods: A retrospective observational study was performed using data from 146 patients with BL and LL leprosy diagnosed and treated at the Souza Araújo Outpatient Clinic, Fiocruz, Rio de Janeiro, Brazil. Clinical, demographic, and hematological data were extracted from medical records. Skin biopsy samples obtained from patients for ENL diagnosis were used for histopathological evaluations. Results: Most patients were male (75%) and had a reactional episode (85%), of which 65% were ENL. Multiple episodes were common, 55% of the 80 patients with ENL presented more than 2 episodes (average of 2.6 episodes). In treatment-naive BL/LL patients, the median blood neutrophil counts of patients who developed ENL at some points of their disease course were higher than those who did not experience any reaction (median= 4,567 cells/mm3 vs 3,731 cells/mm3 respectively, p=0.0286). A correlation between the increase in median neutrophil counts and ENL severity was confirmed (6,066 cells/mm3 for mild ENL vs 10,243 cells/mm3 for moderate/severe ENL, p=0.0009). A longitudinal assessment was also performed in 34 patients, confirming the neutrophilic leukocytosis (BL/LL: 4896 cells/mm3 vs ENL: 8408 cells/mm3, p<0.0001). Moreover, increased NLR was associated with a greater neutrophilic infiltration in ENL lesions. Conclusion: We demonstrate that ENL episodes in patients affected by leprosy are associated with elevated blood leukocyte and neutrophil counts and an increased NLR. These findings highlight the significant involvement of neutrophils in the ENL immunological/inflammatory process.


Assuntos
Eritema Nodoso , Hanseníase Virchowiana , Leucocitose , Neutrófilos , Humanos , Eritema Nodoso/imunologia , Eritema Nodoso/diagnóstico , Eritema Nodoso/etiologia , Masculino , Estudos Retrospectivos , Feminino , Adulto , Neutrófilos/imunologia , Hanseníase Virchowiana/imunologia , Hanseníase Virchowiana/diagnóstico , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Adolescente
16.
Microbes Infect ; 26(4): 105298, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38244764

RESUMO

BACKGROUND: C-C motif chemokine ligand 2, a gene that codes for a protein involved in inflammation. Certain SNPs in the CCL2 gene have been studied for their potential associations with susceptibility to various diseases. These SNPs may affect the production and function of the CCL2 protein, which is involved in the recruitment of immune cells to the site of inflammation. Variations in CCL2 may influence the immune response to Mycobacterium leprae infection. OBJECTIVE: To investigate the association of the C-C motif chemokine ligand-2 single nucleotide polymorphisms with leprosy. METHODS: CCL2 single nucleotide polymorphisms were analyzed in a total of 975 leprosy patients and 357 healthy controls. Of those, 577 leprosy and 288 healthy controls were analyzed by PCR-RFLP for CCL2 -2518 A>G, 535 leprosy and 290 controls for CCL2 -362 G>C, 295 leprosy and 240 controls for CCL2 -2134 T>G, 325 leprosy and 288 controls for CCL2 -1549 A>T SNPs by melting curve analysis using hybridization probe chemistry and detection by fluorescence resonance energy transfer (FRET) technique in Realtime PCR. The levels of CCL2, IL-12p70, IFN-γ, TNF-α, and TGF-ß were estimated in sera samples and correlated with CCL2 genotypes. RESULTS: The frequency of the GCT (-2518 A>G, -362 G>C, -2134 T>G) haplotype is observed to be higher in leprosy patients compared to healthy controls (P = 0.04). There was no significant difference observed in genotypic frequencies between leprosy patients and healthy controls {(-2518A>G, p = 0.53), (-362 G>C, p = 0.01), (-2134 T>G, p = 0.10)}. G allele at the -2134 site is predominant in leprosy (borderline) without any reaction (8 %) compared to borderline patients with RR reactions (2.1 %) (P = 0.03). GG genotype (p = 0.008) and G allele at -2518 (p = 0.030) of the CCL 2 gene were found to be associated with patients with ENL reaction. An elevated level of serum CCL2 was observed in leprosy patients with the -2518 AA and AG genotypes (p = 0.0001). CONCLUSIONS: G allele and GG genotype at the CCL2 -2518 site are associated with a risk of ENL reactions.


Assuntos
Quimiocina CCL2 , Predisposição Genética para Doença , Hanseníase , Polimorfismo de Nucleotídeo Único , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Estudos de Casos e Controles , Quimiocina CCL2/genética , Quimiocina CCL2/sangue , Citocinas/genética , Citocinas/sangue , Frequência do Gene , Genótipo , Hanseníase/genética , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Mycobacterium leprae/genética , Polimorfismo de Fragmento de Restrição
17.
Infect Genet Evol ; 116: 105537, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38056703

RESUMO

BACKGROUND: Leprosy is caused by Mycobacterium leprae and Mycobacterium lepromatosis. Both organisms cannot be cultured in vitro. M. lepromatosis was found to be associated mainly with diffuse lepromatous leprosy and with Lucio's phenomena initially. Later, M. lepromatosis was observed in borderline leprosy cases (BL), lepromatous leprosy cases (LL) and leprosy reactional cases (T1R and ENL). Although many cases are being reported with similar clinical features like Lucio phenomenon in India but M. lepromatosis was not isolated from these cases. The aim of this study was to screen MB patients and patients with type 2 reaction for the presence of M. lepromatosis. METHODOLOGY: We recruited a total of 75 multibacillary leprosy cases (45 MB cases without reaction and 30 type 2 reaction (ENL) cases) from TLM hospitals Purulia (West Bengal), Barabanki (Uttar Pradesh), Shahdara (Delhi) and PGIMER (Chandigarh), India. Punch biopsies of 5 mm were collected in 70% ethanol from all the study subjects. DNA was extracted followed by Hemi-nested PCR targeting 16S rRNA gene specific for M. lepromatosis. Further, PCR products were processed for Sanger sequencing for an absolute confirmation of M. lepromatosis. Whole genome sequencing was done to confirm the presence of M. lepromatosis. RESULT: We observed presence of M. lepromatosis in 4 necrotic ENL patients by heminested PCR. There was 100% 16S rRNA sequence similarity with M. lepromatosis FJ924 in one case, 98.96% in two cases and in one case it was 90.9% similarity by nucleotide BLAST (BLASTn) by using the NCBI website. On the basis of Sanger sequencing, we noted presence of M. lepromatosis in 3 necrotic ENL patients as one sample only gave 90.9% similarity by BLASTn. On the basis of de novo assembly and genome obtained, only one sample S4 with a 2.9 mb genome size was qualified for downstream analysis. Sixteen M. lepromatosis- specific proteins were identified in this case and the closest species was M. lepromatosis strain FJ924 based on whole genome level phylogeny. CONCLUSION: These results provide valuable insights into the prevalence of M. lepromatosis in ENL patients in different regions of India and contribute to our understanding of the genetic characteristics of this pathogen in the context of leprosy.


Assuntos
Hanseníase Virchowiana , Hanseníase , Humanos , Hanseníase Virchowiana/epidemiologia , Hanseníase Virchowiana/microbiologia , Hanseníase Virchowiana/patologia , RNA Ribossômico 16S/genética , Mycobacterium leprae/genética , Hanseníase/microbiologia , Genômica
18.
Narra J ; 3(2): e216, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38450265

RESUMO

Necrotic erythema nodosum leprosum (ENL) is an uncommon manifestation of type 2 lepra reaction, encountered in lepromatous and borderline lepromatous cases of leprosy. Necrotic ENL is associated with the involvement of multiple organs, therefore delayed diagnosis and treatment will lead to complications and poor prognosis. The aim of this case report was to report a challenging case of necrotic ENL misdiagnosed with multiple cellulitis since there were no signs of prior leprosy nor had any antimycobacterial treatment. A 45-year-old man was presented to the surgery department of Dr. Zainoel Abidin Hospital, Banda Aceh, Indonesia, with complaints of fever, joint pain, and painful tender skin lesions with ulceration over the trunk, extremities, and ears for one month. The patient was diagnosed clinically with multiple cellulitis and underwent a debridement procedure. Clinical improvement was absent, the patient was then consulted to the dermatology department. Physical examination showed normal vital signs, madarosis, inguinal lymphadenopathy, thickening of nerves, and sensation of numbness in both hands and feet. Laboratory examinations on admission showed leucocytosis, anemia, thrombocytopenia, hypoalbuminemia, hypocalcemia, and elevated creatinine and ureum level. A slit skin smears examination yielded positive acid-fast bacilli (AFB) with a bacteriological index (BI) value of 3+ and morphological index (MI) of 72%. The patient was diagnosed with lepromatous leprosy with necrotic ENL reaction. Intravenous methylprednisolone and cefoperazone-sulbactam were given. Multidrug therapy mulitbacillary (MDT-MB) without dapsone, and ofloxacin 400 mg was initiated. On day 17, the patient had septic shock. The patient became unconscious and experienced death. This case highlights that medical professionals should be aware of the various manifestations of necrotic ENL to correctly diagnose and provide treatment as soon as possible to prevent mortality, especially in leprosy-endemic country, Indonesia.

19.
Eur J Med Chem ; 248: 115093, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36645983

RESUMO

Eleven-Nineteen-Leukemia Protein (ENL) containing YEATS domain, a potential drug target, has emerged as a reader of lysine acetylation. SGC-iMLLT bearing with benzimidazole scaffold was identified as an effective ENL inhibitor, but with weak activity against mixed-lineage leukemia (MLL)-rearranged cells proliferation. In this study, a series of compounds were designed and synthesized by structural optimization on SGC-iMLLT. All the compounds have been evaluated for their ENL inhibitory activities. The results showed that compounds 13, 23 and 28 are the most potential ones with the IC50 values of 14.5 ± 3.0 nM, 10.7 ± 5.3 nM, and 15.4 ± 2.2 nM, respectively, similar with that of SGC-iMLLT. They could interact with ENL protein and strengthen its thermal stability in vitro. Among them, compound 28 with methyl phenanthridinone moiety replacement of indazole in SGC-iMLLT, exhibited significantly inhibitory activities towards MV4-11 and MOLM-13 cell lines with IC50 values of 4.8 µM and 8.3 µM, respectively, exhibiting ∼7 folds and ∼9 folds more potent inhibition of cell growth than SGC-iMLLT. It could also increase the ENL thermal stability while SGC-iMLLT had no obvious effect on leukemia cells. Moreover, compound 28 could downregulate the expression of target gene MYC either alone or in combination with JQ-1 in cells, which was more effective than SGC-iMLLT. Besides, in vivo pharmacokinetic studies showed that the PK properties for compound 28 was much improved over that of SGC-iMLLT. These observations suggested compound 28 was a potential ligand for ENL-related MLL chemotherapy.


Assuntos
Leucemia , Fatores de Transcrição , Humanos , Linhagem Celular , Histonas/metabolismo , Leucemia/tratamento farmacológico , Leucemia/metabolismo , Proteína de Leucina Linfoide-Mieloide/metabolismo , Domínios Proteicos , Fatores de Transcrição/metabolismo
20.
Front Med (Lausanne) ; 10: 1272404, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020095

RESUMO

Chronic recalcitrant erythema nodosum leprosum (ENL) or type 2 reaction (T2R) is a severe condition found in approximately 50% of multibacillary leprosy subjects. T2R is associated with important morbidities and may lead to several disabilities, not only due to nerve damage but also due to the prolonged use of corticosteroids, thalidomide, or immunosuppressors. We describe here four leprosy patients with chronic recalcitrant ENL treated with cyclophosphamide pulse therapy. All subjects had been on prednisone and thalidomide therapy for at least 30 months but showed inflammatory activity when doses were reduced. Pulse therapy with 1.0 g of cyclophosphamide was used every 4-6 weeks for a minimum of three applications. After pulse therapy, all cases presented total or partial regression of symptoms, and we were able to taper thalidomide and prednisone doses, with better control of ENL, avoiding further hospital admissions and disabilities. No side effects were observed during or after infusion therapy. Cyclophosphamide pulse therapy may be useful and safe to control chronic recalcitrant ENL.

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