RESUMO
Understanding the biological and clinical impact of copy number aberrations (CNAs) on the development of precision therapies in cancer remains an unmet challenge. Genetic amplification of chromosome 1q (chr1q-amp) is a major CNA conferring an adverse prognosis in several types of cancer, including in the blood cancer multiple myeloma (MM). Although several genes across chromosome 1 (chr1q) portend high-risk MM disease, the underpinning molecular etiology remains elusive. Here, with reference to the 3-dimensional (3D) chromatin structure, we integrate multi-omics data sets from patients with MM with genetic variables to obtain an associated clinical risk map across chr1q and to identify 103 adverse prognosis genes in chr1q-amp MM. Prominent among these genes, the transcription factor PBX1 is ectopically expressed by genetic amplification and epigenetic activation of its own preserved 3D regulatory domain. By binding to reprogrammed superenhancers, PBX1 directly regulates critical oncogenic pathways and a FOXM1-dependent transcriptional program. Together, PBX1 and FOXM1 activate a proliferative gene signature that predicts adverse prognosis across multiple types of cancer. Notably, pharmacological disruption of the PBX1-FOXM1 axis with existing agents (thiostrepton) and a novel PBX1 small molecule inhibitor (T417) is selectively toxic against chr1q-amp myeloma and solid tumor cells. Overall, our systems medicine approach successfully identifies CNA-driven oncogenic circuitries, links them to clinical phenotypes, and proposes novel CNA-targeted therapy strategies in MM and other types of cancer.
Assuntos
Mieloma Múltiplo , Cromossomos Humanos Par 1/metabolismo , Proteína Forkhead Box M1/genética , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Fator de Transcrição 1 de Leucemia de Células Pré-B/genética , Prognóstico , Análise de Sistemas , Fatores de Transcrição/genéticaRESUMO
Multiple myeloma (MM) is a disease which remains incurable. One of the main reasons is a weakened immune system that allows MM cells to survive. Therefore, the current research is focused on the study of immune system imbalance in MM to find the most effective immunotherapy strategies. Aiming to identify the key points of immune failure in MM patients, we analysed peripheral lymphocytes subsets from MM patients (n = 57) at various stages of the disease course and healthy individuals (HI, n = 15) focusing on T, NK, iNKT, B cells and NK-cell cytokines. Our analysis revealed that MM patients exhibited immune alterations in all studied immune subsets. Compared to HI, MM patients had a significantly lower proportion of CD4 + T cells (19.55% vs. 40.85%; p < 0.001) and CD4 + iNKT cells (18.8% vs. 40%; p < 0.001), within B cells an increased proportion of CD21LCD38L subset (4.5% vs. 0.4%; p < 0.01) and decreased level of memory cells (unswitched 6.1% vs. 14.7%; p < 0.001 and switched 7.8% vs. 11.2%; NS), NK cells displaying signs of activation and exhaustion characterised by a more than 2-fold increase in SLAMF7 MFI (p < 0.001), decreased expression of NKG2D (MFI) and NKp46 (%) on CD16 + 56 + and CD16 + 56- subset respectively (p < 0.05), Effective immunotherapy needs to consider these immune defects and monitoring of the immune status of MM patients is essential to define better interventions in the future.
RESUMO
Melanotic cutaneous lupus erythematosus (LE) is a newly described clinical variant of chronic cutaneous LE, presenting with localized or diffuse brownish or grayish macular and reticulated pigmentation in the absence of erythema, scaling, atrophy, scarring, or telangiectasia. The diagnosis is based upon histopathology, which demonstrates the characteristic features of LE with an interface vacuolar dermatitis with melanophages, and a superficial and deep, perivascular and periadnexal lymphocytic infiltrate with mucin deposition. Herein, we describe a case of a 61-year-old White male presenting with melanotic cutaneous LE with a blaschkoid distribution on his face in which the histopathological phenomenon of "true melanocytic nests" in the setting of a lichenoid pattern was seen. We want to highlight how nests of cellular aggregates at the dermoepidermal junction labeling with melanocytic markers may occur in the setting of an interface tissue reaction. This benign reactional pattern may mimic atypical melanocytic proliferations, especially on sun-damaged skin. Clinicopathological correlation and careful microscopic examination using a panel of multiple melanocytic markers is crucial for making an accurate final diagnosis. All the cases of melanotic cutaneous LE reported in the literature are also reviewed.
Assuntos
Dermatite , Lúpus Eritematoso Cutâneo , Lúpus Eritematoso Discoide , Humanos , Masculino , Pessoa de Meia-Idade , Melanócitos/patologia , Lúpus Eritematoso Cutâneo/diagnóstico , Lúpus Eritematoso Cutâneo/patologia , Lúpus Eritematoso Discoide/patologia , Dermatite/patologia , Diagnóstico DiferencialRESUMO
Cancer cells can survive chemotherapy-induced stress, but how they recover from it is not known. Using a temporal multiomics approach, we delineate the global mechanisms of proteotoxic stress resolution in multiple myeloma cells recovering from proteasome inhibition. Our observations define layered and protracted programs for stress resolution that encompass extensive changes across the transcriptome, proteome, and metabolome. Cellular recovery from proteasome inhibition involved protracted and dynamic changes of glucose and lipid metabolism and suppression of mitochondrial function. We demonstrate that recovering cells are more vulnerable to specific insults than acutely stressed cells and identify the general control nonderepressable 2 (GCN2)-driven cellular response to amino acid scarcity as a key recovery-associated vulnerability. Using a transcriptome analysis pipeline, we further show that GCN2 is also a stress-independent bona fide target in transcriptional signature-defined subsets of solid cancers that share molecular characteristics. Thus, identifying cellular trade-offs tied to the resolution of chemotherapy-induced stress in tumor cells may reveal new therapeutic targets and routes for cancer therapy optimization.
Assuntos
Neoplasias/tratamento farmacológico , Estresse Fisiológico/efeitos dos fármacos , Antineoplásicos/farmacologia , Autofagia/fisiologia , Linhagem Celular Tumoral , Humanos , Metaboloma/genética , Mitocôndrias/metabolismo , Mieloma Múltiplo/metabolismo , Neoplasias/metabolismo , Neoplasias/fisiopatologia , Inibidores de Proteassoma/farmacologia , Proteólise , Proteoma/genética , Análise de Sistemas , Transcriptoma/genéticaRESUMO
BACKGROUND: COronaVIrus Disease 19 (COVID-19) is associated with a wide spectrum of skin manifestations, but SARS-CoV-2 RNA in lesional skin has been demonstrated only in few cases. OBJECTIVE: The objective of this study was to demonstrate SARS-CoV-2 presence in skin samples from patients with different COVID-19-related cutaneous phenotypes. METHODS: Demographic and clinical data from 52 patients with COVID-19-associated cutaneous manifestations were collected. Immunohistochemistry and digital PCR (dPCR) were performed in all skin samples. RNA in situ hybridization (ISH) was used to confirm the presence of SARS-CoV-2 RNA. RESULTS: Twenty out of 52 (38%) patients presented SARS-CoV-2 positivity in the skin. Among these, 10/52 (19%) patients tested positive for spike protein on immunohistochemistry, five of whom had also positive testing on dPCR. Of the latter, one tested positive both for ISH and ACE-2 on immunohistochemistry while another one tested positive for nucleocapsid protein. Twelve patients showed positivity only for nucleocapsid protein on immunohistochemistry. CONCLUSIONS: SARS-CoV-2 was detected only in 38% of patients, without any association with a specific cutaneous phenotype, suggesting that the pathophysiology of cutaneous lesions mostly depends on the activation of the immune system. The combination of spike and nucleocapsid immunohistochemistry has higher diagnostic yield than dPCR. Skin persistence of SARS-CoV-2 may depend on timing of skin lesions, viral load, and immune response.
Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Imuno-Histoquímica , RNA Viral/análise , RNA Viral/metabolismo , Proteínas do Nucleocapsídeo/genética , Proteínas do Nucleocapsídeo/metabolismo , Reação em Cadeia da Polimerase , Biópsia , Teste para COVID-19RESUMO
Multiple myeloma is a malignancy of plasma cells initiated and driven by primary and secondary genetic events. However, myeloma plasma cell survival and proliferation might be sustained by non-genetic drivers. Z-DNA-binding protein 1 (ZBP1; also known as DAI) is an interferon-inducible, Z-nucleic acid sensor that triggers RIPK3-MLKL-mediated necroptosis in mice. ZBP1 also interacts with TBK1 and the transcription factor IRF3 but the function of this interaction is unclear, and the role of the ZBP1-IRF3 axis in cancer is not known. Here we show that ZBP1 is selectively expressed in late B-cell development in both human and murine cells and it is required for optimal T-cell-dependent humoral immune responses. In myeloma plasma cells, the interaction of constitutively expressed ZBP1 with TBK1 and IRF3 results in IRF3 phosphorylation. IRF3 directly binds and activates cell cycle genes, in part through co-operation with the plasma cell lineage-defining transcription factor IRF4, thereby promoting myeloma cell proliferation. This generates a novel, potentially therapeutically targetable and relatively selective myeloma cell addiction to the ZBP1-IRF3 axis. Our data also show a noncanonical function of constitutive ZBP1 in human cells and expand our knowledge of the role of cellular immune sensors in cancer biology.
Assuntos
Mieloma Múltiplo , Animais , Proliferação de Células , Humanos , Imunidade Inata , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Camundongos , Mieloma Múltiplo/genética , Fosforilação , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismoRESUMO
BACKGROUND: The most common Italian rickettsiosis is Mediterranean Spotted Fever (MSF). MSF is commonly associated with a symptom triad consisting of fever, cutaneous rash, and inoculation eschar. The rash is usually maculopapular but, especially in severe presentations, may be petechial. Other typical findings are arthromyalgia and headache. Herein, we describe for the first time an unusual case of Israeli spotted fever (ISF) associated with interstitial pneumonia and pleural effusion in which R. conorii subsp. israelensis was identified by molecular methods in the blood, as well as in the pleural fluid. CASE PRESENTATION: A 72-year-old male presented with a 10-day history of remittent fever. On admission, the patient's general condition appeared poor with confusion and drowsiness; the first assessment revealed a temperature of 38.7°, blood pressure of 110/70 mmHg, a blood oxygen saturation level of 80% with rapid, frequent, and superficial breathing using accessory muscles (28 breaths per minute), and an arrhythmia with a heart rate of 90 beats per minute. qSOFA score was 3/3. Chest CT revealed ground-glass pneumonia with massive pleural effusion. Petechial exanthema was present diffusely, including on the palms and soles, and a very little eschar surrounded by a violaceous halo was noted on the dorsum of the right foot. Awaiting the results of blood cultures, broad-spectrum antibiotic therapy with meropenem 1 g q8h, ciprofloxacin 400 mg q12h, and doxycycline 100 mg q12h was initiated. Doxycycline was included in the therapy because of the presence of petechial rash and fever, making us consider a diagnosis of rickettsiosis. This suspicion was confirmed by the positivity of polymerase chain reaction on whole blood for R. conorii subsp. israelensis. Thoracentesis was performed to improve alveolar ventilation. R. conorii subsp. israelensis was again identified in the pleural fluid by PCR technique. On day 4 the clinical condition worsened. Blood exams showed values suggestive of secondary hemophagocytic lymphohistiocytosis; 4 out of 8 diagnostic criteria were present and empirical treatment with prednisone was started resulting in a gradual improvement in general condition. CONCLUSIONS: Israeli spotted fever may be a severe disease. A high index of suspicion is required to promptly start life-saving therapy. Pleural effusion and interstitial pneumonia may be part of the clinical picture of severe rickettsial disease and should not lead the physician away from this diagnosis.
Assuntos
Febre Botonosa , Derrame Pleural , Infecções por Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Idoso , Febre Botonosa/diagnóstico , Febre Botonosa/tratamento farmacológico , Humanos , Itália , Masculino , Derrame Pleural/diagnóstico , Derrame Pleural/tratamento farmacológicoRESUMO
ABSTRACT: We report the case of a 63-year-old white man who, 3 days after stent removal of endoscopic drainage of pancreatic cysts, developed a penile necrosis due to purpura fulminans (PF) that has been misdiagnosed as Fournier's gangrene. Penile necrosis was rapidly followed by a lethal multiorgan failure due to disseminated intravascular coagulopathy (DIC), triggered by the subsequent development of a severe acute pancreatitis. PF describes a rare syndrome involving intravascular thrombosis and hemorrhagic infarction of the skin. Although reports of penile necrosis secondary to various causes are documented in the literature, penile necrosis secondary to PF in the setting of acute pancreatitis is a rare event. Histopathologic studies of the skin showing an occlusive nonvasculitic vasculopathy are the first step to achieve an accurate diagnosis.
Assuntos
Gangrena de Fournier/patologia , Doenças do Pênis/patologia , Pênis/patologia , Púrpura Fulminante/patologia , Erros de Diagnóstico , Coagulação Intravascular Disseminada/etiologia , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Necrose , Doenças do Pênis/etiologia , Púrpura Fulminante/etiologiaRESUMO
ABSTRACT: One of the most common patterns of presentations that have been described in COVID-19 patients includes the erythematous/papular/morbilliform eruptions. However, actually, the diffuse exanthems containing macules and papules were not specific to COVID-19, and even histopathology does not show any specific signs that could help to differentiate COVID-19 skin lesions from non-COVID-19 causes such as drugs or other viral infections. We present the case of a COVID-19-positive woman with a morbilliform rash, whose skin biopsy showed the presence of some peculiar cytopathic epidermal changes that could represent a possible distinctive histopathological feature related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection The presence of viral particles in the keratinocytes with additional positivity of endothelial cells and eccrine glands by immunohistochemistry using an anti-SARS-CoV-2 Spike S1 antibodies supports a causal relation of the lesions with SARS-CoV-2 infection.
Assuntos
COVID-19/complicações , Exantema/patologia , Exantema/virologia , Adulto , Feminino , Humanos , Queratinócitos/patologia , Queratinócitos/virologia , SARS-CoV-2RESUMO
DRESS/DiHS is a complex and potentially fatal drug reaction. Little is known about risk factors and elements that can help to identify patients with a severe reaction early. The aim of the study was to investigate those factors favoring the disease and its severity by analyzing the clinical conditions and therapies preceding the reaction. We conducted a retrospective analysis on patients admitted to our center between 2010 and 2020 who were discharged with a diagnosis of DRESS. We used the RegiSCAR diagnostic criteria. We defined the severity of DRESS using the criteria of Mizukawa et al. We included 25 patients (15 females) with a median age of 66 years. Skin involvement, eosinophilia, and liver injury were the most important aspects. Allopurinol was found to be the most involved drug. Reaction severity was significantly associated with the number of daily medications (p=0.0067) and an age of at least 68 years (p=0.013). In addition, 75% of severe cases had at least three comorbidities in history, and most of the severe cases were female. In our study the advanced age, the high number of comorbidities and home therapies, and the inflammatory state were found to be predisposing elements to the development of the disease and its severity.
Assuntos
Síndrome de Hipersensibilidade a Medicamentos , Eosinofilia , Índice de Gravidade de Doença , Dermatopatias , Idoso , Comorbidade , Síndrome de Hipersensibilidade a Medicamentos/epidemiologia , Síndrome de Hipersensibilidade a Medicamentos/terapia , Eosinofilia/epidemiologia , Eosinofilia/terapia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Dermatopatias/epidemiologia , Dermatopatias/terapiaRESUMO
Intellectual disability (ID) is characterized by impairments in the cognitive processes and in the tasks of daily life. It encompasses a clinically and genetically heterogeneous group of neurodevelopmental disorders often associated with autism spectrum disorder (ASD). Social and communication abilities are strongly compromised in ASD. The prevalence of ID/ASD is 1-3%, and approximately 30% of the patients remain without a molecular diagnosis. Considering the extreme genetic locus heterogeneity, next-generation sequencing approaches have provided powerful tools for candidate gene identification. Molecular diagnosis is crucial to improve outcome, prevent complications, and hopefully start a therapeutic approach. Here, we performed parent-offspring trio whole-exome sequencing (WES) in a cohort of 60 mostly syndromic ID/ASD patients and we detected 8 pathogenic variants in genes already known to be associated with ID/ASD (SYNGAP1, SMAD6, PACS1, SHANK3, KMT2A, KCNQ2, ACTB, and POGZ). We found four de novo disruptive variants of four novel candidate ASD/ID genes: MBP, PCDHA1, PCDH15, PDPR. We additionally selected via bioinformatic tools many variants in unknown genes that alone or in combination can contribute to the phenotype. In conclusion, our data confirm the efficacy of WES in detecting pathogenic variants of known and novel ID/ASD genes.
Assuntos
Transtorno Autístico/genética , Sequenciamento do Exoma , Loci Gênicos , Predisposição Genética para Doença , Deficiência Intelectual/genética , Adolescente , Transtorno Autístico/patologia , Criança , Feminino , Humanos , Deficiência Intelectual/patologia , MasculinoRESUMO
Relapsed acute myeloid leukemia (AML) is a significant post-transplant complication lacking standard treatment and associated with a poor prognosis. Cellular therapy, which is already widely used as a treatment for several hematological malignancies, could be a potential treatment alternative. Natural killer (NK) cells play an important role in relapse control but can be inhibited by the leukemia cells highly positive for HLA class I. In order to restore NK cell activity after their ex vivo activation, NK cells can be combined with conditioning target cells. In this study, we tested NK cell activity against KG1a (AML cell line) with and without two types of pretreatment-Ara-C treatment that induced NKG2D ligands (increased activating signal) and/or blocking of HLA-KIR (killer-immunoglobulin-like receptors) interaction (decreased inhibitory signal). Both treatments improved NK cell killing activity. Compared with target cell killing of NK cells alone (38%), co-culture with Ara-C treated KG1a target cells increased the killing to 80%. Anti-HLA blocking antibody treatment increased the proportion of dead KG1a cells to 53%. Interestingly, the use of the combination treatment improved the killing potential to led to the death of 85% of KG1a cells. The combination of Ara-C and ex vivo activation of NK cells has the potential to be a feasible approach to treat relapsed AML after hematopoietic stem cell transplantation.
Assuntos
Imunoterapia/métodos , Células Matadoras Naturais/imunologia , Leucemia Mieloide Aguda/terapia , Linhagem Celular Tumoral , Células Cultivadas , Ensaios Clínicos como Assunto , Citarabina/farmacologia , Humanos , Imunossupressores/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/transplante , Leucemia Mieloide Aguda/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Receptores KIR/imunologia , Transdução de SinaisRESUMO
Dysphagia in patients with lung cancer is usually due to direct invasion from bronchogenic carcinomas or nodal localizations, while metastases from distant lung neoplasms are considered rare. We report a case of a smooth esophageal narrowing secondary to intramural metastasis from pulmonary adenocarcinoma in a patient with no previous history of neoplasia. Since standard linear echoendoscope could not overpass the malignant stricture, we obtained a histological diagnosis by fine-needle aspiration biopsy using an echobronchoscope (EBUS), due to its lower diameter. The EBUS scope represents a valuable tool to obtain cytological specimens in patients with esophageal strictures.
Assuntos
Transtornos de Deglutição/etiologia , Neoplasias Esofágicas/secundário , Estenose Esofágica/complicações , Biópsia por Agulha Fina , Endossonografia , Neoplasias Esofágicas/diagnóstico , Estenose Esofágica/diagnóstico , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
Despite encouraging therapeutic advances, multiple myeloma (MM) remains an incurable malignancy. The exciting results of chimaeric antigen receptor (CAR)-based immunotherapy in CD19(+) B-cell malignancies have spurred a great interest in extending the use of the CAR technology to other cancers, including MM. Availability of a specific, tumour-restricted antigen is crucial for the design of successful antibody-based CAR therapy. However, in MM, as in other malignancies, the relative dearth of such antigens-targets represents the main obstacle for the wider pre-clinical development and clinical application of the CAR technology. Here we provide an overview of the current progress and future promises of CAR technology in MM therapy. We highlight that, owing to its complexity, phenotypic and functional heterogeneity and the impact of the microenvironment, MM poses several challenges for CAR-based therapeutic approaches. Nevertheless, for the same reasons, MM can serve as a paradigm for better understanding, optimization and overall improvement of the CAR technology for the benefit of cancer and myeloma patients.
Assuntos
Imunoterapia/métodos , Mieloma Múltiplo/tratamento farmacológico , Antígenos de Neoplasias/imunologia , Humanos , Engenharia de Proteínas , Receptores de Antígenos/genética , Receptores de Antígenos/uso terapêuticoRESUMO
A rare point mutation in the core promoter -270GC-rich box of PIGM, a housekeeping gene, disrupts binding of the generic transcription factor (TF) Sp1 and causes inherited glycosylphosphatidylinositol (GPI) deficiency (IGD). We show that whereas PIGM messenger RNA levels and surface GPI expression in IGD B cells are low, GPI expression is near normal in IGD erythroid cells. This divergent phenotype results from differential promoter chromatin accessibility and binding of Sp1. Specifically, whereas PIGM transcription in B cells is dependent on Sp1 binding to the -270GC-rich box and is associated with lower promoter accessibility, in erythroid cells, Sp1 activates PIGM transcription by binding upstream of (but not to) the -270GC-rich box. These findings explain intact PIGM transcription in IGD erythroid cells and the lack of clinically significant intravascular hemolysis in patients with IGD. Furthermore, they provide novel insights into tissue-specific transcriptional control of a housekeeping gene by a generic TF.
Assuntos
Glicosilfosfatidilinositóis/deficiência , Hemoglobinúria Paroxística/genética , Manosiltransferases/genética , Ativação Transcricional , Linfócitos B/metabolismo , Linfócitos B/patologia , Eritrócitos/metabolismo , Eritrócitos/patologia , Glicosilfosfatidilinositóis/genética , Glicosilfosfatidilinositóis/metabolismo , Hemoglobinúria Paroxística/metabolismo , Hemoglobinúria Paroxística/patologia , Humanos , Mutação , Fenótipo , Regiões Promotoras Genéticas , Convulsões , Fator de Transcrição Sp1/metabolismoRESUMO
HDAC inhibitors (HDACi) increase transcription of some genes through histone hyperacetylation. To test the hypothesis that HDACi-mediated enhanced transcription might be of therapeutic value for inherited enzyme deficiency disorders, we focused on the glycolytic and pentose phosphate pathways (GPPPs). We show that among the 16 genes of the GPPPs, HDACi selectively enhance transcription of glucose 6-phosphate dehydrogenase (G6PD). This requires enhanced recruitment of the generic transcription factor Sp1, with commensurate recruitment of histone acetyltransferases and deacetylases, increased histone acetylation, and polymerase II recruitment to G6PD. These G6PD-selective transcriptional and epigenetic events result in increased G6PD transcription and ultimately restored enzymatic activity in B cells and erythroid precursor cells from patients with G6PD deficiency, a disorder associated with acute or chronic hemolytic anemia. Therefore, restoration of enzymatic activity in G6PD-deficient nucleated cells is feasible through modulation of G6PD transcription. Our findings also suggest that clinical consequences of pathogenic missense mutations in proteins with enzymatic function can be overcome in some cases by enhancement of the transcriptional output of the affected gene.
Assuntos
Epigênese Genética/efeitos dos fármacos , Deficiência de Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/biossíntese , Glucosefosfato Desidrogenase/genética , Inibidores de Histona Desacetilases/farmacologia , Transcrição Gênica/efeitos dos fármacos , Células Cultivadas , Imunoprecipitação da Cromatina , Deficiência de Glucosefosfato Desidrogenase/enzimologia , Humanos , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The bromodomain and extraterminal (BET) protein BRD2-4 inhibitors hold therapeutic promise in preclinical models of hematologic malignancies. However, translation of these data to molecules suitable for clinical development has yet to be accomplished. Herein we expand the mechanistic understanding of BET inhibitors in multiple myeloma by using the chemical probe molecule I-BET151. I-BET151 induces apoptosis and exerts strong antiproliferative effect in vitro and in vivo. This is associated with contrasting effects on oncogenic MYC and HEXIM1, an inhibitor of the transcriptional activator P-TEFb. I-BET151 causes transcriptional repression of MYC and MYC-dependent programs by abrogating recruitment to the chromatin of the P-TEFb component CDK9 in a BRD2-4-dependent manner. In contrast, transcriptional upregulation of HEXIM1 is BRD2-4 independent. Finally, preclinical studies show that I-BET762 has a favorable pharmacologic profile as an oral agent and that it inhibits myeloma cell proliferation, resulting in survival advantage in a systemic myeloma xenograft model. These data provide a strong rationale for extending the clinical testing of the novel antimyeloma agent I-BET762 and reveal insights into biologic pathways required for myeloma cell proliferation.
Assuntos
Antineoplásicos/uso terapêutico , Benzodiazepinas/uso terapêutico , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzodiazepinas/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Camundongos , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição , Ativação Transcricional/efeitos dos fármacos , Células Tumorais CultivadasRESUMO
Multiple myeloma (MM) is an incurable tumor of the plasma cells, the terminally differentiated immunoglobulin secreting B lineage cells. The genetic make-up of MM has been extensively characterized but its impact on the biology of the disease is incomplete without more precise knowledge of the identity and functional role of cells with multiple myeloma propagating activity (MMPA). We review here recent data that link MMPA with myeloma clonotypic populations organized in a cellular hierarchy that mirrors normal B cell development and also with drug resistance and disease relapse. We further propose a conceptual framework which, with optimal use of recent technological advances in genomics and phenomics, could allow dissection of the cellular and molecular properties of cells with MMPA, drug resistance and in vivo relapse in an integrated and patient-specific manner. There is real hope that these approaches will significantly contribute to further improvements in disease control, overall survival, and possibly cure of patients with MM.
Assuntos
Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/imunologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/imunologiaRESUMO
BACKGROUND: Early postnatal exposure to general anesthesia (GA) may be detrimental to brain development, resulting in long-term cognitive impairments. Older literature suggests that in utero exposure of rodents to GA causes cognitive impairments in the first-generation as well as in the second-generation offspring never exposed to GA. Thus, the authors hypothesize that transient exposure to GA during critical stages of synaptogenesis causes epigenetic changes in chromatin with deleterious effects on transcription of target genes crucial for proper synapse formation and cognitive development. They focus on the effects of GA on histone acetyltransferase activity of cAMP-responsive element-binding protein and the histone-3 acetylation status in the promoters of the target genes brain-derived neurotrophic factor and cellular Finkel-Biskis-Jinkins murine sarcoma virus osteosarcoma oncogene (c-Fos) known to regulate the development of neuronal morphology and function. METHODS: Seven-day-old rat pups were exposed to a sedative dose of midazolam followed by combined nitrous oxide and isoflurane anesthesia for 6 h. Hippocampal neurons and organotypic hippocampal slices were cultured in vitro and exposed to GA for 24 h. RESULTS: GA caused epigenetic modulations manifested as histone-3 hypoacetylation (decrease of 25 to 30%, n = 7 to 9) and fragmentation of cAMP-responsive element-binding protein (two-fold increase, n = 6) with 25% decrease in its histone acetyltransferase activity, which resulted in down-regulated transcription of brain-derived neurotrophic factor (0.2- to 0.4-fold, n = 7 to 8) and cellular Finkel-Biskis-Jinkins murine sarcoma virus osteosarcoma oncogene (about 0.2-fold, n = 10 to 12). Reversal of histone hypoacetylation with sodium butyrate blocked GA-induced morphological and functional impairments of neuronal development and synaptic communication. CONCLUSION: Long-term impairments of neuronal development and synaptic communication could be caused by GA-induced epigenetic phenomena.