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Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma, accounting for around 30-60% of all cases. The management of DLBCL in Asia has several unmet needs due to the diversity of the population, the heterogeneity of local clinical guidelines for DLBCL and the wide disparity in resources and healthcare systems across different regions. Rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP) is widely recognized as the standard first-line treatment for DLBCL; however, alternative regimens are required to improve patient outcomes in challenging subtypes, such as patients with high International Prognostic Index scores, old/frail patients, and patients with double-hit and double-expressor DLBCL or concurrent central nervous system disease. This review article draws from the expertise of practicing hematologists/oncologists in the region, with the aim of integrating data from current scientific evidence to address the unmet needs and unique socioeconomic challenges faced by challenging high risk patient groups in the Asia-Pacific region.
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Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma Difuso de Grandes Células B , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ásia/epidemiologia , Ciclofosfamida/uso terapêutico , Vincristina/uso terapêuticoRESUMO
BACKGROUND: Patients with hematological malignancies (HM) were at a high risk of developing severe disease from coronavirus disease 2019 (COVID-19). We aimed to assess the clinical outcome of COVID-19 in hospitalized patients with HM. METHODS: Adult patients with HM who were hospitalized with a laboratory-confirmed COVID-19 between May, 2021 and November, 2022 were retrospectively identified. Primary outcome was respiratory failure requiring mechanical ventilation or mortality within 60 days after hospitalization. We also analyzed associated factors for de-isolation (defined as defervescence with a consecutive serial cycle threshold value > 30) within 28 days. RESULTS: Of 152 eligible patients, 22 (14.5%) developed respiratory failure or mortality in 60 days. Factors associated with developing respiratory failure that required mechanical ventilation or mortality included receipt of allogeneic hematopoietic stem-cell transplantation (allo-HSCT) (adjusted hazards ratio [aHR], 5.10; 95% confidence interval [CI], 1.64-15.85), type 2 diabetes mellitus (aHR, 2.47; 95% CI, 1.04-5.90), lymphopenia at admission (aHR, 6.85; 95% CI, 2.45-19.15), and receiving <2 doses of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines (aHR, 3.00; 95% CI, 1.19-7.60). Ninety-nine (65.1%) patients were de-isolated in 28 days, against which two hazardous factors were identified: receipt of B-cell depletion therapies within one year prior to COVID-19 (aHR, 0.55, 95% CI, 0.35-0.87) and lymphopenia upon admission (aHR, 0.65; 95% CI, 0.43-1.00). CONCLUSION: We found a high rate of respiratory failure and mortality among patients with HM who contracted the SARS-CoV-2. Factors associated with developing respiratory failure or mortality in 60 days included receipt of allo-HSCT, type 2 diabetes mellitus and lymphopenia upon admission. Having received ≥2 doses of vaccination conferred protection against clinical progression.
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COVID-19 , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , SARS-CoV-2 , Humanos , COVID-19/complicações , COVID-19/mortalidade , COVID-19/epidemiologia , Neoplasias Hematológicas/complicações , Masculino , Pessoa de Meia-Idade , Feminino , Fatores de Risco , Estudos Retrospectivos , Idoso , Adulto , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Índice de Gravidade de Doença , Insuficiência Respiratória/epidemiologia , Respiração Artificial , Hospitalização/estatística & dados numéricos , Linfopenia , Diabetes Mellitus Tipo 2/complicaçõesAssuntos
Transtornos de Deglutição , Estomatite , Humanos , Dieta , Deglutição , Estomatite/etiologiaRESUMO
PURPOSE: The main purpose of surgery for cervical lymphoma is only for tissue sampling. To establish a patient-friendly diagnostic approach, we investigated the feasibility of ultrasound-guided core biopsy with flow cytometry in the patients with suspected cervical lymphoma. METHODS: We prospectively recruited patients with suspected cervical lymphoma from Nov 2017 till Jan 2021 in a referral medical center and performed retrospective interpretation of the prospectively acquired data. Ultrasound-guided core biopsy as the tissue sampling approach for the targeted lesions was performed in all patients. The ultrasound-guided core biopsy samples were analyzed by immunohistochemical stains and flow cytometry. The sample quality and the rate of definite and decisive diagnosis obtained by ultrasound-guided core biopsy alone and ultrasound-guided core biopsy with flow cytometry were evaluated. RESULTS: Total 81 consecutive patients were recruited for analysis. All ultrasound-guided core biopsy samples were qualified for analysis of pathology and flow cytometry. Pathologically, the diagnoses were definite and compatible with their flow cytometry results in 70 patients (86.42%). Either newly-diagnosed or recurrent cervical lymphoma/lymphoproliferative disorders with histologic transformation could be diagnosed by ultrasound-guided core biopsy with flow cytometry. Nine of the 11 patients with pathologically indefinite diagnosis became clinically decisive when flow cytometry was incorporated into the process, which improved the rate of decisive diagnosis to 98.77% (Odds ratio [95% CI]: 6.21 [1.28, 58.96]). CONCLUSION: Ultrasound-guided core biopsy combined with flow cytometry is suggested to serve as the first-line and patient-friendly diagnostic approach for the patients with suspected cervical lymphoma.
Assuntos
Linfoma , Humanos , Citometria de Fluxo/métodos , Estudos Retrospectivos , Linfoma/diagnóstico por imagem , Linfoma/patologia , Biópsia com Agulha de Grande Calibre , Biópsia Guiada por Imagem/métodos , Ultrassonografia de IntervençãoRESUMO
BACKGROUND/PURPOSE: The early progression of disease (POD) of Hodgkin lymphoma (HL) leads to a poor prognosis. To identify risk factors for early POD, this retrospective two-center cohort analysis was conducted. METHODS: Medical records of HL patients between 1998 and 2020 from two referral centers were reviewed. RESULTS: Two-hundred and sixty-nine patients were analyzed. The distribution of early vs. advanced stages was 51.1 vs. 48.9%, respectively. The 5-year progression free survival (PFS) was 63%, and the overall survival (OS) was 87% with a median follow-up of 52.0 months. The complete remission (CR) rate was 85.7%. Disease progression or relapsed disease occurred in 33.9% (n = 85) of patients while 17.0% of this cohort had early POD within 12 months of induction therapy. Patients with early POD had a worse median OS than those without (p < 0.001). Failure to achieve post-induction CR and high international prognostic score (IPS, 3-7) were independent risk factors for early POD. Compared with chemotherapy alone, consolidative radiotherapy after induction chemotherapy was associated with a lower risk of early POD (21.3% vs. 6.2%, p = 0.006). CONCLUSION: High IPS was an independent risk factor for early POD, which was less observed in those with consolidative radiotherapy.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Intervalo Livre de Doença , Doença de Hodgkin/tratamento farmacológico , Humanos , Prognóstico , Indução de Remissão , Estudos RetrospectivosRESUMO
Polatuzumab vedotin (PoV) has recently shown promising activity when combined with rituximab-bendamustine (BR) in patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). However, few studies have described the prognostic factors predicting response. Here, we aimed to evaluate the efficacy and safety profile of PoV-based chemotherapy, including regimens other than BR, as third-line or beyond treatment for patients with R/R DLBCL and to explore prognostic factors. Overall, 40 patients, including 37 with de novo and 3 with transformed DLBCL, were enrolled. The overall response rate was 52.5%, and 25% and 27.5% of patients showed a complete response and partial response, respectively. With a median follow-up of 18.8 months, the median overall survival (OS) of the total cohort was 8.5 months, and that of those receiving subsequent hematopoietic stem cell transplantation (HSCT) was 24 months. Low/intermediate risk according to the revised International Prognostic Index score at diagnosis and before PoV treatment predicted better OS. Furthermore, a normal lactate dehydrogenase level and an absolute lymphocyte count/absolute monocyte count ratio > 1.5 were favorable OS prognostic factors. The most common adverse event was cytopenia, with 42.5% of patients developing febrile neutropenia. Grade 1-3 peripheral neuropathy associated with PoV was reported in 25% of patients and resolved in most patients after the cessation of treatment. In summary, we demonstrated that PoV combined with either BR or other intensive chemotherapy is an effective and well-tolerated salvage option for patients with R/R DLBCL. Subsequent HSCT has the potential to further improve survival outcomes in this high-risk population. Clinicaltrials.gov number: NCT05006534.
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Anticorpos Monoclonais/uso terapêutico , Imunoconjugados/uso terapêutico , Linfoma Difuso de Grandes Células B/terapia , Recidiva Local de Neoplasia/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cloridrato de Bendamustina/efeitos adversos , Cloridrato de Bendamustina/uso terapêutico , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Imunoconjugados/efeitos adversos , Imunoterapia/efeitos adversos , Linfoma Difuso de Grandes Células B/diagnóstico , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Prognóstico , Terapia de Salvação , Análise de Sobrevida , Resultado do Tratamento , Adulto JovemRESUMO
INTRODUCTION: Histopathological characteristics of cytomegalovirus (CMV) lymphadenitis have been well described. Rare studies have reported the immune status and clinical features. Clinically, experts believed that CMV lymphadenitis develops in immunocompromised and immunocompetent patients. Infectious mononucleosis (IM)-like syndrome is the most well-known clinical presentation. METHODS: We reviewed archived CMV immunohistochemical stains on lymphoid tissues. The clinicopathological features of CMV-positive cases were studied. RESULTS: For lymph nodes, we detected CMV in 29% (5/17) allogeneic peripheral blood hematopoietic stem cell transplantation (PBSCT) recipients, 29% (4/14) post-autologous PBSCT patients, 13% (6/47) patients treated with intravenous chemotherapy, and 9% (9/96) immunocompetent patients. We detected CMV in 7% (2/24) of tonsils but not in the nasopharynx, tongue base, or spleen specimens. The patients with iatrogenic immunodeficiency ranged from 37 to 76 years old. CMV infections developed a few years after lymphoma treatment (median duration after allogeneic PBSCT, 932 days; after autologous PBSCT, 370 days; and after chemotherapy, 626 days). The most common clinical presentation was neck mass (13/25, 42%), followed by asymptomatic image finding (10/25, 40%). Positron emission tomography/computed tomography (PET/CT) scan showed increased uptake compared to the liver in all patients (11/11, 100%). Of 10 lymphoma patients, 8 (80%) had a Deauville score of 4-5; they accounted for 30% (8/27) of lymphoma patients with false-positive PET/CT scan results. All cases were self-limiting. 96% (23/25) cases had Epstein-Barr virus coinfection, and EBER-positive cells were predominantly in a few germinal centers. CONCLUSIONS: Cytomegalovirus (CMV) lymphadenitis and tonsillitis were subclinical infections, not primary CMV infection with IM-like syndrome. The lymphadenopathy typically developed a few years after lymphoma treatments in the middle-aged and the elderly. The lesions mimicked lymphoma relapse in PET scans. Therefore, recognizing CMV infection in lymphoid tissues is of clinical importance.
RESUMO
Short-term calorie reduction (SCR) requires individuals to reduce their calorie intake to less than 50% of normal requirements and has shown good tolerance and potential benefits in prior studies addressing gynecological cancer patients. More studies are needed to further confirm its safety, feasibility, and effects in patients with different cancers, including hematological malignancies. This pilot cohort study with a matched-pair comparison group was registered at ClinicalTrails.gov [201810112RIND]. Adult patients diagnosed with advanced-stage diffuse large-B cell lymphoma were recruited (SCR group) and matched with one comparison patient (comparison group), each in a manner blinded to their outcomes. The SCR group undertook at least two cycles of 48 h water fast along with their chemotherapy R-CHOP. Descriptive analysis and generalized estimating equations were used to analyze the data. Six participants completed multiple cycles of SCR and were compared to their six counterparts in the comparison group. The results showed that SCR is safe and feasible in terms of a high compliance rate and stable nutritional status. The SCR was associated with benefits in post-chemotherapy hematological parameters (i.e., erythrocyte [p < 0.001] and lymphocyte counts [p < 0.001]). More randomized controlled trials are needed to validate the effects of SCR on different types of cancer populations.
Assuntos
Restrição Calórica/métodos , Quimioterapia de Indução/métodos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Restrição Calórica/efeitos adversos , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Ciclofosfamida/uso terapêutico , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Estudos de Viabilidade , Feminino , Humanos , Linfoma Difuso de Grandes Células B/dietoterapia , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Projetos Piloto , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Rituximab/administração & dosagem , Rituximab/efeitos adversos , Rituximab/uso terapêutico , Resultado do Tratamento , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Vincristina/uso terapêuticoRESUMO
γδ T cells are a distinct subgroup of T cells that bridge the innate and adaptive immune system and can attack cancer cells in an MHC-unrestricted manner. Trials of adoptive γδ T cell transfer in solid tumors have had limited success. Here, we show that DNA methyltransferase inhibitors (DNMTis) upregulate surface molecules on cancer cells related to γδ T cell activation using quantitative surface proteomics. DNMTi treatment of human lung cancer potentiates tumor lysis by ex vivo-expanded Vδ1-enriched γδ T cells. Mechanistically, DNMTi enhances immune synapse formation and mediates cytoskeletal reorganization via coordinated alterations of DNA methylation and chromatin accessibility. Genetic depletion of adhesion molecules or pharmacological inhibition of actin polymerization abolishes the potentiating effect of DNMTi. Clinically, the DNMTi-associated cytoskeleton signature stratifies lung cancer patients prognostically. These results support a combinatorial strategy of DNMTis and γδ T cell-based immunotherapy in lung cancer management.
Assuntos
Citoesqueleto/metabolismo , Citotoxicidade Imunológica/genética , Epigênese Genética , Sinapses Imunológicas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Animais , Linhagem Celular Tumoral , Citoesqueleto/efeitos dos fármacos , Citotoxicidade Imunológica/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/metabolismo , Decitabina/farmacologia , Inibidores Enzimáticos/farmacologia , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Sinapses Imunológicas/efeitos dos fármacos , Marcação por Isótopo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/genética , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/metabolismo , Masculino , Camundongos Endogâmicos NOD , Fosfotirosina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sobrevida , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoAssuntos
Janus Quinase 2/genética , Mutação de Sentido Incorreto , Mielofibrose Primária , Proteínas Repressoras/genética , Idoso , Alelos , Substituição de Aminoácidos , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mielofibrose Primária/genética , Mielofibrose Primária/mortalidade , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Recent preclinical studies have shown the potential benefits of short-term calorie reduction (SCR) on cancer treatment. In this integrative review, we aimed to identify and synthesize current evidence regarding the feasibility, process, and effects of SCR in cancer patients receiving chemotherapy. PubMed, Cumulative Index to Nursing and Allied Health Literature, Ovid Medline, PsychINFO, and Embase were searched for original research articles using various combinations of Medical Subject Heading terms. Among the 311 articles identified, seven studies met the inclusion criteria. The majority of the reviewed studies were small randomized controlled trials or cohort study with fair quality. The results suggest that SCR is safe and feasible. SCR is typically arranged around the chemotherapy, with the duration ranging from 24 to 96 h. Most studies examined the protective effects of SCR on normal cells during chemotherapy. The evidence supports that SCR had the potential to enhance both the physical and psychological wellbeing of patients during chemotherapy. SCR is a cost-effective intervention with great potential. Future well-controlled studies with sufficient sample sizes are needed to examine the full and long-term effects of SCR and its mechanism of action.
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Restrição Calórica/métodos , Neoplasias/tratamento farmacológico , Estudos de Viabilidade , Humanos , Tempo , Resultado do TratamentoRESUMO
Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma often with extranodal involvement at diagnosis, and yet how this feature correlates with survival awaits elucidation. To address this issue, a correlative analysis between clinical features of 127 MCL patients and their overall survival (OS) was conducted. In this cohort, the median age at MCL diagnosis was 62 years and 81% were males. Eighty-four percent of patients were Ann Arbor stage 4, and 15% were blastoid variants. In patients with gastrointestinal MCL, approximately 40% had gastric involvement. In treatment, CHOP-based induction chemotherapy was given to 61.1% of patients. One-third of patients undertook autologous stem cell transplant (SCT), and 4.7% had allogeneic SCT. The median OS was 82 months and well-stratified in MIPI risk groups. In the multivariate analysis for OS, blastoid variants and gastric involvement were both independent risk factors whereas auto-SCT had a protective effect. Overall, this study corroborated with the current understandings and international therapeutic standards for MCL. Auto-SCT associated with a better OS while allo-SCT remained an option for blastoid variants and those who failed Auto-SCT. Interestingly, patients with gastric involvement tended to have worse survival, a finding that spawns more studies to investigate the mechanism.
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Neoplasias Gastrointestinais/mortalidade , Neoplasias Gastrointestinais/terapia , Linfoma de Célula do Manto/mortalidade , Linfoma de Célula do Manto/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prognóstico , Indução de Remissão , Transplante de Células-Tronco , Taiwan/epidemiologia , Transplante Autólogo , Transplante Homólogo , Vincristina/administração & dosagemAssuntos
Proteínas de Ligação a DNA/genética , Herpesvirus Humano 4 , Linfoma Extranodal de Células T-NK/genética , Proteínas Proto-Oncogênicas/genética , Idoso , Proteínas de Ligação a DNA/metabolismo , Dioxigenases , Humanos , Linfoma Extranodal de Células T-NK/metabolismo , Masculino , Proteínas Proto-Oncogênicas/metabolismoRESUMO
BACKGROUND: Multicolor flow cytometry (MFC) analysis is widely used to identify minimal residual disease (MRD) after treatment for acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). However, current manual interpretation suffers from drawbacks of time consuming and interpreter idiosyncrasy. Artificial intelligence (AI), with the expertise in assisting repetitive or complex analysis, represents a potential solution for these drawbacks. METHODS: From 2009 to 2016, 5333 MFC data from 1742 AML or MDS patients were collected. The 287 MFC data at post-induction were selected as the outcome set for clinical outcome validation. The rest were 4:1 randomized into the training set (nâ¯=â¯4039) and the validation set (nâ¯=â¯1007). AI algorithm learned a multi-dimensional MFC phenotype from the training set and input it to support vector machine (SVM) classifier after Gaussian mixture model (GMM) modeling, and the performance was evaluated in The validation set. FINDINGS: Promising accuracies (84·6% to 92·4%) and AUCs (0·921-0·950) were achieved by the developed algorithms. Interestingly, the algorithm from even one testing tube achieved similar performance. The clinical significance was validated in the outcome set, and normal MFC interpreted by the AI predicted better progression-free survival (10·9 vs 4·9â¯months, pâ¯<â¯0·0001) and overall survival (13·6 vs 6·5â¯months, pâ¯<â¯0·0001) for AML. INTERPRETATION: Through large-scaled clinical validation, we showed that AI algorithms can produce efficient and clinically-relevant MFC analysis. This approach also possesses a great advantage of the ability to integrate other clinical tests. FUND: This work was supported by the Ministry of Science and Technology (107-2634-F-007-006 and 103-2314-B-002-185-MY2) of Taiwan.
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Citometria de Fluxo , Leucemia Mieloide Aguda/sangue , Leucemia Mieloide Aguda/mortalidade , Aprendizado de Máquina , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Mieloide Aguda/terapia , Masculino , Síndromes Mielodisplásicas/terapia , Neoplasia Residual , Valor Preditivo dos Testes , Taxa de SobrevidaRESUMO
Members of the adenine nucleotide translocase (ANT) family exchange ADP for ATP across the mitochondrial inner membrane, an activity that is essential for oxidative phosphorylation (OXPHOS). Mutations in or dysregulation of ANTs is associated with progressive external ophthalmoplegia, cardiomyopathy, nonsyndromic intellectual disability, apoptosis, and the Warburg effect. Binding partners of human ANTs have not been systematically identified. The absence of such information has prevented a detailed molecular understanding of the assorted ANT-associated diseases, including insight into their disparate phenotypic manifestations. To fill this void, in this study, we define the interactomes of two human ANT isoforms. Analogous to its yeast counterpart, human ANTs associate with heterologous partner proteins, including the respiratory supercomplex (RSC) and other solute carriers. The evolutionarily conserved ANT-RSC association is particularly noteworthy because the composition, and thereby organization, of RSCs in yeast and human is different. Surprisingly, absence of the major ANT isoform only modestly impairs OXPHOS in HEK293 cells, indicating that the low levels of other isoforms provide functional redundancy. In contrast, pharmacological inhibition of OXPHOS expression and function inhibits ANT-dependent ADP/ATP exchange. Thus ANTs and the OXPHOS machinery physically interact and functionally cooperate to enhance ANT transport capacity and mitochondrial respiration.
Assuntos
Translocases Mitocondriais de ADP e ATP/genética , Translocases Mitocondriais de ADP e ATP/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Apoptose , Células HEK293 , Células HeLa , Humanos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Fosforilação Oxidativa , Isoformas de Proteínas/metabolismo , Relação Estrutura-AtividadeRESUMO
Epstein-Barr virus (EBV) is etiologically linked to infectious mononucleosis and several human cancers. EBV encodes a conserved protein kinase BGLF4 that plays a key role in the viral life cycle. To provide new insight into the host proteins regulated by BGLF4, we utilized stable isotope labeling by amino acids in cell culture (SILAC)-based quantitative proteomics to compare site-specific phosphorylation in BGLF4-expressing Akata B cells. Our analysis revealed BGLF4-mediated hyperphosphorylation of 3,046 unique sites corresponding to 1,328 proteins. Frequency analysis of these phosphosites revealed a proline-rich motif signature downstream of BGLF4, indicating a broader substrate recognition for BGLF4 than its cellular ortholog cyclin-dependent kinase 1 (CDK1). Further, motif analysis of the hyperphosphorylated sites revealed enrichment in ATM, ATR and Aurora kinase substrates while functional analyses revealed significant enrichment of pathways related to the DNA damage response (DDR), mitosis and cell cycle. Phosphorylation of proteins associated with the mitotic spindle assembly checkpoint (SAC) indicated checkpoint activation, an event that inactivates the anaphase promoting complex/cyclosome, APC/C. Furthermore, we demonstrated that BGLF4 binds to and directly phosphorylates the key cellular proteins PP1, MPS1 and CDC20 that lie upstream of SAC activation and APC/C inhibition. Consistent with APC/C inactivation, we found that BGLF4 stabilizes the expression of many known APC/C substrates. We also noted hyperphosphorylation of 22 proteins associated the nuclear pore complex, which may contribute to nuclear pore disassembly and SAC activation. A drug that inhibits mitotic checkpoint activation also suppressed the accumulation of extracellular EBV virus. Taken together, our data reveal that, in addition to the DDR, manipulation of mitotic kinase signaling and SAC activation are mechanisms associated with lytic EBV replication. All MS data have been deposited in the ProteomeXchange with identifier PXD002411 (http://proteomecentral.proteomexchange.org/dataset/PXD002411).
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Dano ao DNA/fisiologia , Infecções por Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/metabolismo , Mitose/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Virais/metabolismo , Replicação Viral/fisiologia , Sequência de Aminoácidos , Linhagem Celular , Cromatografia Líquida , Regulação Viral da Expressão Gênica , Humanos , Immunoblotting , Dados de Sequência Molecular , Fosforilação , Proteômica/métodos , Transdução de Sinais/fisiologia , Espectrometria de Massas em TandemRESUMO
Resistance to chemotherapy represents a major obstacle for long-term remission, and effective strategies to overcome drug resistance would have significant clinical impact. We report that recurrent ovarian carcinomas after paclitaxel/carboplatin treatment have higher levels of spleen tyrosine kinase (SYK) and phospho-SYK. In vitro, paclitaxel-resistant cells expressed higher SYK, and the ratio of phospho-SYK/SYK positively associated with paclitaxel resistance in ovarian cancer cells. Inactivation of SYK by inhibitors or gene knockdown sensitized paclitaxel cytotoxicity in vitro and in vivo. Analysis of the phosphotyrosine proteome in paclitaxel-resistant tumor cells revealed that SYK phosphorylates tubulins and microtubule-associated proteins. Inhibition of SYK enhanced microtubule stability in paclitaxel-resistant tumor cells that were otherwise insensitive. Thus, targeting SYK pathway is a promising strategy to enhance paclitaxel response.