RESUMO
Most cell-surface receptors for cytokines and growth factors signal as dimers, but it is unclear whether remodeling receptor dimer topology is a viable strategy to "tune" signaling output. We utilized diabodies (DA) as surrogate ligands in a prototypical dimeric receptor-ligand system, the cytokine Erythropoietin (EPO) and its receptor (EpoR), to dimerize EpoR ectodomains in non-native architectures. Diabody-induced signaling amplitudes varied from full to minimal agonism, and structures of these DA/EpoR complexes differed in EpoR dimer orientation and proximity. Diabodies also elicited biased or differential activation of signaling pathways and gene expression profiles compared to EPO. Non-signaling diabodies inhibited proliferation of erythroid precursors from patients with a myeloproliferative neoplasm due to a constitutively active JAK2V617F mutation. Thus, intracellular oncogenic mutations causing ligand-independent receptor activation can be counteracted by extracellular ligands that re-orient receptors into inactive dimer topologies. This approach has broad applications for tuning signaling output for many dimeric receptor systems.
Assuntos
Receptores da Eritropoetina/química , Receptores da Eritropoetina/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , Linhagem Celular , Cristalografia por Raios X , Dimerização , Eritropoetina/metabolismo , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Camundongos , Modelos Moleculares , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Mutação Puntual , Engenharia de Proteínas , Receptores da Eritropoetina/agonistas , Receptores da Eritropoetina/antagonistas & inibidores , Alinhamento de SequênciaRESUMO
BACKGROUND: Adjuvant pembrolizumab therapy after surgery for renal-cell carcinoma was approved on the basis of a significant improvement in disease-free survival in the KEYNOTE-564 trial. Whether the results regarding overall survival from the third prespecified interim analysis of the trial would also favor pembrolizumab was uncertain. METHODS: In this phase 3, double-blind, placebo-controlled trial, we randomly assigned (in a 1:1 ratio) participants with clear-cell renal-cell carcinoma who had an increased risk of recurrence after surgery to receive pembrolizumab (at a dose of 200 mg) or placebo every 3 weeks for up to 17 cycles (approximately 1 year) or until recurrence, the occurrence of unacceptable toxic effects, or withdrawal of consent. A significant improvement in disease-free survival according to investigator assessment (the primary end point) was shown previously. Overall survival was the key secondary end point. Safety was a secondary end point. RESULTS: A total of 496 participants were assigned to receive pembrolizumab and 498 to receive placebo. As of September 15, 2023, the median follow-up was 57.2 months. The disease-free survival benefit was consistent with that in previous analyses (hazard ratio for recurrence or death, 0.72; 95% confidence interval [CI], 0.59 to 0.87). A significant improvement in overall survival was observed with pembrolizumab as compared with placebo (hazard ratio for death, 0.62; 95% CI, 0.44 to 0.87; P = 0.005). The estimated overall survival at 48 months was 91.2% in the pembrolizumab group, as compared with 86.0% in the placebo group; the benefit was consistent across key subgroups. Pembrolizumab was associated with a higher incidence of serious adverse events of any cause (20.7%, vs. 11.5% with placebo) and of grade 3 or 4 adverse events related to pembrolizumab or placebo (18.6% vs. 1.2%). No deaths were attributed to pembrolizumab therapy. CONCLUSIONS: Adjuvant pembrolizumab was associated with a significant and clinically meaningful improvement in overall survival, as compared with placebo, among participants with clear-cell renal-cell carcinoma at increased risk for recurrence after surgery. (Funded by Merck Sharp and Dohme, a subsidiary of Merck; KEYNOTE-564 ClinicalTrials.gov number, NCT03142334.).
Assuntos
Antineoplásicos Imunológicos , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , Adjuvantes Imunológicos/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/cirurgia , Método Duplo-Cego , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/mortalidade , Neoplasias Renais/cirurgia , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Intervalo Livre de Doença , Terapia Combinada , Análise de SobrevidaRESUMO
The thrombopoietin receptor (TpoR) plays a central role in myeloproliferative neoplasms (MPNs). Mutations in JAK2, calreticulin, or TpoR itself drive the constitutive activation of TpoR and uncontrolled proliferation and differentiation of hematopoietic stem cells and progenitors. The JAK2 V617F mutation is responsible for most MPNs, and all driver mutants induce pathologic TpoR activation. Existing therapeutic strategies have focused on JAK2 kinase inhibitors that are unable to differentiate between the mutated MPN clone and healthy cells. Surprisingly, the targeting of TpoR itself has remained poorly explored despite its central role in pathology. Here, we performed a comprehensive characterization of human TpoR activation under physiological and pathological conditions, focusing on the JAK2 V617F mutant. Using a system of controlled dimerization of the transmembrane and cytosolic domains of TpoR, we discovered that human TpoR (hTpoR) adopts different dimeric conformations upon Tpo-induced vs JAK2 V617F-mediated activation. We identified the amino acids and specific dimeric conformation of hTpoR responsible for activation in complex with JAK2 V617F and confirmed our findings in the full-length receptor context in hematopoietic cell lines and primary bone marrow cells. Remarkably, we found that the modulation of hTpoR conformations by point mutations allowed for specific inhibition of JAK2 V617F-driven activation without affecting Tpo-induced signaling. Our results demonstrate that modulation of the hTpoR conformation is a viable therapeutic strategy for JAK2 V617F-positive MPNs and set the path for novel drug development by identifying precise residues of hTpoR involved in JAK2 V617F-specific activation.
Assuntos
Transtornos Mieloproliferativos , Receptores de Trombopoetina , Humanos , Receptores de Trombopoetina/metabolismo , Citocinas/genética , Transtornos Mieloproliferativos/genética , Mutação , Transdução de Sinais , Janus Quinase 2/metabolismoRESUMO
Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by the clonal expansion of myeloid cells, notably megakaryocytes (MKs), and an aberrant cytokine production leading to bone marrow (BM) fibrosis and insufficiency. Current treatment options are limited. TGF-ß1, a profibrotic and immunosuppressive cytokine, is involved in PMF pathogenesis. While all cell types secrete inactive, latent TGF-ß1, only a few activate the cytokine via cell type-specific mechanisms. The cellular source of the active TGF-ß1 implicated in PMF is not known. Transmembrane protein GARP binds and activates latent TGF-ß1 on the surface of regulatory T lymphocytes (Tregs) and MKs or platelets. Here, we found an increased expression of GARP in the BM and spleen of mice with PMF and tested the therapeutic potential of a monoclonal antibody (mAb) that blocks TGF-ß1 activation by GARP-expressing cells. GARP:TGF-ß1 blockade reduced not only fibrosis but also the clonal expansion of transformed cells. Using mice carrying a genetic deletion of Garp in either Tregs or MKs, we found that the therapeutic effects of GARP:TGF-ß1 blockade in PMF imply targeting GARP on Tregs. These therapeutic effects, accompanied by increased IFN-γ signals in the spleen, were lost upon CD8 T-cell depletion. Our results suggest that the selective blockade of TGF-ß1 activation by GARP-expressing Tregs increases a CD8 T-cell-mediated immune reaction that limits transformed cell expansion, providing a novel approach that could be tested to treat patients with myeloproliferative neoplasms.
Assuntos
Mielofibrose Primária , Fator de Crescimento Transformador beta1 , Camundongos , Animais , Mielofibrose Primária/tratamento farmacológico , Mielofibrose Primária/genética , Mielofibrose Primária/metabolismo , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/metabolismo , Citocinas/metabolismo , Fibrose , Linfócitos T ReguladoresRESUMO
Mutant calreticulin (CALR) proteins resulting from a -1/+2 frameshifting mutation of the CALR exon 9 carry a novel C-terminal amino acid sequence and drive the development of myeloproliferative neoplasms (MPNs). Mutant CALRs were shown to interact with and activate the thrombopoietin receptor (TpoR/MPL) in the same cell. We report that mutant CALR proteins are secreted and can be found in patient plasma at levels up to 160 ng/mL, with a mean of 25.64 ng/mL. Plasma mutant CALR is found in complex with soluble transferrin receptor 1 (sTFR1) that acts as a carrier protein and increases mutant CALR half-life. Recombinant mutant CALR proteins bound and activated the TpoR in cell lines and primary megakaryocytic progenitors from patients with mutated CALR in which they drive thrombopoietin-independent colony formation. Importantly, the CALR-sTFR1 complex remains functional for TpoR activation. By bioluminescence resonance energy transfer assay, we show that mutant CALR proteins produced in 1 cell can specifically interact in trans with the TpoR on a target cell. In comparison with cells that only carry TpoR, cells that carry both TpoR and mutant CALR are hypersensitive to exogenous mutant CALR proteins and respond to levels of mutant CALR proteins similar to those in patient plasma. This is consistent with CALR-mutated cells that expose TpoR carrying immature N-linked sugars at the cell surface. Thus, secreted mutant CALR proteins will act more specifically on the MPN clone. In conclusion, a chaperone, CALR, can turn into a rogue cytokine through somatic mutation of its encoding gene.
Assuntos
Transtornos Mieloproliferativos , Neoplasias , Humanos , Citocinas/metabolismo , Calreticulina/genética , Transtornos Mieloproliferativos/genética , Mutação , Fatores Imunológicos , Janus Quinase 2/genéticaRESUMO
BACKGROUND: Patients with renal-cell carcinoma who undergo nephrectomy have no options for adjuvant therapy to reduce the risk of recurrence that have high levels of supporting evidence. METHODS: In a double-blind, phase 3 trial, we randomly assigned, in a 1:1 ratio, patients with clear-cell renal-cell carcinoma who were at high risk for recurrence after nephrectomy, with or without metastasectomy, to receive either adjuvant pembrolizumab (at a dose of 200 mg) or placebo intravenously once every 3 weeks for up to 17 cycles (approximately 1 year). The primary end point was disease-free survival according to the investigator's assessment. Overall survival was a key secondary end point. Safety was a secondary end point. RESULTS: A total of 496 patients were randomly assigned to receive pembrolizumab, and 498 to receive placebo. At the prespecified interim analysis, the median time from randomization to the data-cutoff date was 24.1 months. Pembrolizumab therapy was associated with significantly longer disease-free survival than placebo (disease-free survival at 24 months, 77.3% vs. 68.1%; hazard ratio for recurrence or death, 0.68; 95% confidence interval [CI], 0.53 to 0.87; P = 0.002 [two-sided]). The estimated percentage of patients who remained alive at 24 months was 96.6% in the pembrolizumab group and 93.5% in the placebo group (hazard ratio for death, 0.54; 95% CI, 0.30 to 0.96). Grade 3 or higher adverse events of any cause occurred in 32.4% of the patients who received pembrolizumab and in 17.7% of those who received placebo. No deaths related to pembrolizumab therapy occurred. CONCLUSIONS: Pembrolizumab treatment led to a significant improvement in disease-free survival as compared with placebo after surgery among patients with kidney cancer who were at high risk for recurrence. (Funded by Merck Sharp and Dohme, a subsidiary of Merck; KEYNOTE-564 ClinicalTrials.gov number, NCT03142334.).
Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Nefrectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/cirurgia , Quimioterapia Adjuvante/efeitos adversos , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Humanos , Análise de Intenção de Tratamento , Neoplasias Renais/mortalidade , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva , Análise de SobrevidaRESUMO
Indistinguishability between photons is a key requirement for scalable photonic quantum technologies. We experimentally demonstrate that partly distinguishable single photons can be purified to reach near-unity indistinguishability by the process of quantum interference with ancillary photons followed by heralded detection of a subset of them. We report on the indistinguishability of the purified photons by interfering two purified photons and show improvements in the photon indistinguishability of 2.774(3)% in the low-noise regime, and as high as 10.2(5)% in the high-noise regime.
RESUMO
Polycythemia vera (PV) is a clonal disorder arising from the acquired somatic mutations of the JAK2 gene, including JAK2V617F or several others in exon 12. A 38-year-old female had a stroke at age 32 and found to have elevated hemoglobin, normal leukocytes, normal platelets, and tested negative for JAK2V617F and exon 12 mutations. Next generation sequencing revealed a novel mutation: JAK2R715T in the pseudokinase domain (JH2) at 47.5%. Its presence in her nail DNA confirmed a germline origin. Her mother and her son similarly had erythrocytosis and a JAK2R715T mutation. Computer modeling indicated gain-of-function JAK2 activity. The propositus and her mother had polyclonal myelopoiesis, ruling out another somatic mutation-derived clonal hematopoiesis. Some erythroid progenitors of all three generations grew without erythropoietin, a hallmark of PV. The in vitro reporter assay confirmed increased activity of the JAK2R715T kinase. Similar to PV, the JAK2R715T native cells have increased STAT5 phosphorylation, augmented transcripts of prothrombotic and inflammatory genes, and decreased KLF2 transcripts. The propositus was not controlled by hydroxyurea, and JAK2 inhibitors were not tolerated; however, Ropeginterferon-alfa-2b (Ropeg-IFN-α) induced a remission. Ropeg-IFN-α treatment also reduced JAK2 activity in the propositus, her mother and JAK2V617F PV subjects. We report dominantly inherited erythrocytosis secondary to a novel germline JAK2R715T gain-of-function mutation with many but not all comparable molecular features to JAK2V617F PV. We also document a previously unreported inhibitory mechanism of JAK2 signaling by Ropeg-IFN-α.
Assuntos
Mutação em Linhagem Germinativa , Janus Quinase 2 , Policitemia , Adulto , Feminino , Humanos , Mutação com Ganho de Função , Interferon-alfa/uso terapêutico , Janus Quinase 2/genética , Linhagem , Policitemia/genética , Policitemia/tratamento farmacológico , Policitemia Vera/genética , Policitemia Vera/tratamento farmacológicoRESUMO
BACKGROUND: The COVID-19 pandemic restrictions posed challenges to maintaining healthy lifestyles and physical well-being. During the first mobility restrictions from March to mid-July 2020, the German population was advised to stay home, except for work, exercise, and essential shopping. Our objective was to comprehensively assess the impact of these restrictions on changes in physical activity and sedentary behavior to identify the most affected groups. METHODS: Between April 30, 2020, and May 12, 2020, we distributed a COVID-19-specific questionnaire to participants of the German National Cohort (NAKO). This questionnaire gathered information about participants' physical activity and sedentary behavior currently compared to the time before the restrictions. We integrated this new data with existing information on anxiety, depressive symptoms, and physical activity. The analyses focused on sociodemographic factors, social relationships, physical health, and working conditions. RESULTS: Out of 152,421 respondents, a significant proportion reported altered physical activity and sedentary behavioral patterns due to COVID-19 restrictions. Over a third of the participants initially meeting the WHO's physical activity recommendation could no longer meet the guidelines during the restrictions. Participants reported substantial declines in sports activities (mean change (M) = -0.38; 95% CI: -.390; -.378; range from -2 to + 2) and reduced active transportation (M = -0.12; 95% CI: -.126; -.117). However, they also increased recreational physical activities (M = 0.12; 95% CI: .117; .126) while engaging in more sedentary behavior (M = 0.24; 95% CI: .240; .247) compared to pre-restriction levels. Multivariable linear and log-binomial regression models indicated that younger adults were more affected by the restrictions than older adults. The shift to remote work, self-rated health, and depressive symptoms were the factors most strongly associated with changes in all physical activity domains, including sedentary behavior, and the likelihood to continue following the physical activity guidelines. CONCLUSIONS: Mobility patterns shifted towards inactivity or low-intensity activities during the nationwide restrictions in the spring of 2020, potentially leading to considerable and lasting health risks.
Assuntos
COVID-19 , Corrida , Humanos , Idoso , Comportamento Sedentário , Pandemias , COVID-19/epidemiologia , Exercício Físico , Alemanha/epidemiologiaRESUMO
BACKGROUND: This was a first-in-human Phase 1/2 open-label dose-escalation study of the novel checkpoint kinase 1 (Chk1) inhibitor SRA737. METHODS: Patients with advanced solid tumours enrolled in dose-escalation cohorts and received SRA737 monotherapy orally on a continuous daily (QD) dosing schedule in 28-day cycles. Expansion cohorts included up to 20 patients with prospectively selected, pre-specified response predictive biomarkers. RESULTS: In total, 107 patients were treated at dose levels from 20-1300 mg. The maximum tolerated dose (MTD) of SRA737 was 1000 mg QD, the recommended Phase 2 dose (RP2D) was 800 mg QD. Common toxicities of diarrhoea, nausea and vomiting were generally mild to moderate. Dose-limiting toxicity at daily doses of 1000 and 1300 mg QD SRA737 included gastrointestinal events, neutropenia and thrombocytopenia. Pharmacokinetic analysis at the 800 mg QD dose showed a mean Cmin of 312 ng/mL (546 nM), exceeding levels required to cause growth delay in xenograft models. No partial or complete responses were seen. CONCLUSIONS: SRA737 was well tolerated at doses that achieved preclinically relevant drug concentrations but single agent activity did not warrant further development as monotherapy. Given its mechanism of action resulting in abrogating DNA damage repair, further clinical development of SRA737 should be as combination therapy. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT02797964.
Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/induzido quimicamente , Compostos Heterocíclicos de 4 ou mais Anéis , Inibidores de Proteínas Quinases , Vômito/induzido quimicamente , Dose Máxima Tolerável , Relação Dose-Resposta a DrogaRESUMO
PURPOSE: The development of oestrogen resistance is a major challenge in managing hormone-sensitive metastatic breast cancer. Saracatinib (AZD0530), an oral Src kinase inhibitor, prevents oestrogen resistance in animal models and reduces osteoclast activity. We aimed to evaluate the efficacy of saracatinib addition to aromatase inhibitors (AI) in patients with hormone receptor-positive metastatic breast cancer. METHODS: This phase II multicentre double-blinded randomised trial allocated post-menopausal women to AI with either saracatinib or placebo (1:1 ratio). Patients were stratified into an "AI-sensitive/naïve" group who received anastrozole and "prior-AI" group who received exemestane. Primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR) and toxicity. RESULTS: 140 patients were randomised from 20 UK centres to saracatinib/AI (n = 69) or placebo/AI (n = 71). Saracatinib was not associated with an improved PFS (3.7 months v. 5.6 months placebo/AI) and did not reduce likelihood of bony progression. There was no benefit in OS or ORR. Effects were consistent in "AI-sensitive/naive" and "prior-AI" sub-groups. Saracatinib was well tolerated with dose reductions in 16% and the main side effects were gastrointestinal, hypophosphatemia and rash. CONCLUSION: Saracatinib did not improve outcomes in post-menopausal women with metastatic breast cancer. There was no observed beneficial effect on bone metastases. CRUKE/11/023, ISRCTN23804370.
Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/patologia , Inibidores da Aromatase/efeitos adversos , Aromatase , Estrogênios/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
Congenital amegakaryocytic thrombocytopenia (CAMT) is a severe inherited thrombocytopenia due to loss-of-function mutations affecting the thrombopoietin (TPO) receptor, MPL. Here, we report a new homozygous MPL variant responsible for CAMT in 1 consanguineous family. The propositus and her sister presented with severe thrombocytopenia associated with mild anemia. Next-generation sequencing revealed the presence of a homozygous MPLR464G mutation resulting in a weak cell-surface expression of the receptor in platelets. In cell lines, we observed a defect in MPLR464G maturation associated with its retention in the endoplasmic reticulum. The low cell-surface expression of MPLR464G induced very limited signaling with TPO stimulation, leading to survival and reduced proliferation of cells. Overexpression of a myeloproliferative neoplasm-associated calreticulin (CALR) mutant did not rescue trafficking of MPLR464G to the cell surface and did not induce constitutive signaling. However, it unexpectedly restored a normal response to eltrombopag (ELT), but not to TPO. This effect was only partially mimicked by the purified recombinant CALR mutant protein. Finally, the endogenous CALR mutant was able to restore the megakaryocyte differentiation of patient CD34+ cells carrying MPLR464G in response to ELT.
Assuntos
Benzoatos/farmacologia , Calreticulina , Síndrome Congênita de Insuficiência da Medula Óssea , Hidrazinas/farmacologia , Mutação de Sentido Incorreto , Pirazóis/farmacologia , Receptores de Trombopoetina , Trombocitopenia , Adulto , Substituição de Aminoácidos , Calreticulina/genética , Calreticulina/metabolismo , Criança , Pré-Escolar , Síndrome Congênita de Insuficiência da Medula Óssea/tratamento farmacológico , Síndrome Congênita de Insuficiência da Medula Óssea/genética , Síndrome Congênita de Insuficiência da Medula Óssea/metabolismo , Síndrome Congênita de Insuficiência da Medula Óssea/patologia , Feminino , Células HEK293 , Homozigoto , Humanos , Lactente , Masculino , Receptores de Trombopoetina/genética , Receptores de Trombopoetina/metabolismo , Trombocitopenia/tratamento farmacológico , Trombocitopenia/genética , Trombocitopenia/metabolismo , Trombocitopenia/patologiaRESUMO
Somatic mutations of calreticulin (CALR) have been identified as a main disease driver of myeloproliferative neoplasms, suggesting that development of drugs targeting mutant CALR is of great significance. Site-directed mutagenesis in the N-glycan binding domain (GBD) abolishes the ability of mutant CALR to oncogenically activate the thrombopoietin receptor (MPL). We therefore hypothesized that a small molecule targeting the GBD might inhibit the oncogenicity of the mutant CALR. Using an in silico molecular docking study, we identified candidate binders to the GBD of CALR. Further experimental validation of the hits identified a group of catechols inducing a selective growth inhibitory effect on cells that depend on oncogenic CALR for survival and proliferation. Apoptosis-inducing effects by the compound were significantly higher in the CALR-mutated cells than in CALR wild-type cells. Additionally, knockout or C-terminal truncation of CALR eliminated drug hypersensitivity in CALR-mutated cells. We experimentally confirmed the direct binding of the selected compound to CALR, disruption of the mutant CALR-MPL interaction, inhibition of the JAK2-STAT5 pathway, and reduction at the intracellular level of mutant CALR upon drug treatment. Our data indicate that small molecules targeting the GBD of CALR can selectively kill CALR-mutated cells by disrupting the CALR-MPL interaction and inhibiting oncogenic signaling.
Assuntos
Calreticulina/metabolismo , Hematoxilina/farmacologia , Mapas de Interação de Proteínas/efeitos dos fármacos , Receptores de Trombopoetina/metabolismo , Animais , Sítios de Ligação/efeitos dos fármacos , Calreticulina/química , Calreticulina/genética , Linhagem Celular , Descoberta de Drogas , Humanos , Camundongos , Simulação de Acoplamento Molecular , Mutagênese Sítio-Dirigida , Mutação , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Ligação Proteica/efeitos dos fármacos , Receptores de Trombopoetina/químicaRESUMO
Classical BCR-ABL-negative myeloproliferative neoplasms (MPNs) are clonal disorders of hematopoietic stem cells (HSCs) caused mainly by recurrent mutations in genes encoding JAK2 (JAK2), calreticulin (CALR), or the thrombopoietin receptor (MPL). Interferon α (IFNα) has demonstrated some efficacy in inducing molecular remission in MPNs. To determine factors that influence molecular response rate, we evaluated the long-term molecular efficacy of IFNα in patients with MPN by monitoring the fate of cells carrying driver mutations in a prospective observational and longitudinal study of 48 patients over more than 5 years. We measured the clonal architecture of early and late hematopoietic progenitors (84 845 measurements) and the global variant allele frequency in mature cells (409 measurements) several times per year. Using mathematical modeling and hierarchical Bayesian inference, we further inferred the dynamics of IFNα-targeted mutated HSCs. Our data support the hypothesis that IFNα targets JAK2V617F HSCs by inducing their exit from quiescence and differentiation into progenitors. Our observations indicate that treatment efficacy is higher in homozygous than heterozygous JAK2V617F HSCs and increases with high IFNα dose in heterozygous JAK2V617F HSCs. We also found that the molecular responses of CALRm HSCs to IFNα were heterogeneous, varying between type 1 and type 2 CALRm, and a high dose of IFNα correlates with worse outcomes. Our work indicates that the long-term molecular efficacy of IFNα implies an HSC exhaustion mechanism and depends on both the driver mutation type and IFNα dose.
Assuntos
Células-Tronco Hematopoéticas/efeitos dos fármacos , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Mutação/efeitos dos fármacos , Transtornos Mieloproliferativos/tratamento farmacológico , Calreticulina/genética , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Fatores Imunológicos/farmacologia , Interferon-alfa/farmacologia , Janus Quinase 2/genética , Estudos Longitudinais , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Estudos Prospectivos , Receptores de Trombopoetina/genética , Células Tumorais CultivadasRESUMO
BACKGROUND: The randomized controlled clinical trial "TIM-HF2" investigated the benefit of telemonitoring in chronic heart failure. The health economic evaluation of this intervention was based on routine data from statutory health insurance (SHI) funds. Since participants were recruited independently of their SHI affiliation, there was a large number of potential data-providing SHI funds. This resulted in both organizational and methodological challenges, from participation of the data providers to data preparation. METHOD: The procedures are described from study planning and data acquisition to data review and processing in the TIM-HF2 trial. Based on the identification of potential problems for data completeness and data quality, possible solutions have been derived. RESULTS: In total, participants were insured with 49 different SHI funds, which provided routine data for a total of 1450 participants. About half of all initial data deliveries were correct. The most common problems in data preparation occurred in the machine readability of the data. Success factors for a high level of data completeness were close communication with the SHI funds and a high level of time and personnel commitment to intensive data checking and preparation. DISCUSSION: Based on the experience of the TIM-HF2 trial, a high heterogeneity has been detected in data management and transmission of routine data. Universally applicable data descriptions are desired to improve data access, quality, and usability for research purposes.
Assuntos
Administração Financeira , Seguro Saúde , Humanos , Alemanha , Programas Nacionais de Saúde , Relatório de PesquisaRESUMO
BACKGROUND: The first interim analysis of the KEYNOTE-564 study showed improved disease-free survival with adjuvant pembrolizumab compared with placebo after surgery in patients with clear cell renal cell carcinoma at an increased risk of recurrence. The analysis reported here, with an additional 6 months of follow-up, was designed to assess longer-term efficacy and safety of pembrolizumab versus placebo, as well as additional secondary and exploratory endpoints. METHODS: In the multicentre, randomised, double-blind, placebo-controlled, phase 3 KEYNOTE-564 trial, adults aged 18 years or older with clear cell renal cell carcinoma with an increased risk of recurrence were enrolled at 213 hospitals and cancer centres in North America, South America, Europe, Asia, and Australia. Eligible participants had an Eastern Cooperative Oncology Group performance status of 0 or 1, had undergone nephrectomy 12 weeks or less before randomisation, and had not received previous systemic therapy for advanced renal cell carcinoma. Participants were randomly assigned (1:1) via central permuted block randomisation (block size of four) to receive pembrolizumab 200 mg or placebo intravenously every 3 weeks for up to 17 cycles. Randomisation was stratified by metastatic disease status (M0 vs M1), and the M0 group was further stratified by ECOG performance status and geographical region. All participants and investigators involved in study treatment administration were masked to the treatment group assignment. The primary endpoint was disease-free survival by investigator assessment in the intention-to-treat population (all participants randomly assigned to a treatment). Safety was assessed in the safety population, comprising all participants who received at least one dose of pembrolizumab or placebo. As the primary endpoint was met at the first interim analysis, updated data are reported without p values. This study is ongoing, but no longer recruiting, and is registered with ClinicalTrials.gov, NCT03142334. FINDINGS: Between June 30, 2017, and Sept 20, 2019, 994 participants were assigned to receive pembrolizumab (n=496) or placebo (n=498). Median follow-up, defined as the time from randomisation to data cutoff (June 14, 2021), was 30·1 months (IQR 25·7-36·7). Disease-free survival was better with pembrolizumab compared with placebo (HR 0·63 [95% CI 0·50-0·80]). Median disease-free survival was not reached in either group. The most common all-cause grade 3-4 adverse events were hypertension (in 14 [3%] of 496 participants) and increased alanine aminotransferase (in 11 [2%]) in the pembrolizumab group, and hypertension (in 13 [3%] of 498 participants) in the placebo group. Serious adverse events attributed to study treatment occurred in 59 (12%) participants in the pembrolizumab group and one (<1%) participant in the placebo group. No deaths were attributed to pembrolizumab. INTERPRETATION: Updated results from KEYNOTE-564 support the use of adjuvant pembrolizumab monotherapy as a standard of care for participants with renal cell carcinoma with an increased risk of recurrence after nephrectomy. FUNDING: Merck Sharp & Dohme LLC, a subsidiary of Merck & Co, Inc, Rahway, NJ, USA.
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Carcinoma de Células Renais , Hipertensão , Neoplasias Renais , Adulto , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/cirurgia , Método Duplo-Cego , Seguimentos , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/etiologia , Neoplasias Renais/cirurgia , Nefrectomia/efeitos adversosRESUMO
Mutations in the MPL gene encoding the human thrombopoietin receptor (TpoR) drive sporadic and familial essential thrombocythemias (ETs). We identified 2 ET patients harboring double mutations in cis in MPL, namely, L498W-H499C and H499Y-S505N. Using biochemical and signaling assays along with partial saturation mutagenesis, we showed that L498W is an activating mutation potentiated by H499C and that H499C and H499Y enhance the activity of the canonical S505N mutation. L498W and H499C can activate a truncated TpoR mutant, which lacks the extracellular domain, indicating these mutations act on the transmembrane (TM) cytosolic domain. Using a protein complementation assay, we showed that L498W and H499C strongly drive dimerization of TpoR. Activation by tryptophan substitution is exquisitely specific for position 498. Using structure-guided mutagenesis, we identified upstream amino acid W491 as a key residue required for activation by L498W or canonical activating mutations such as S505N and W515K, as well as by eltrombopag. Structural data point to a common dimerization and activation path for TpoR via its TM domain that is shared between the small-molecule agonist eltrombopag and canonical and novel activating TpoR mutations that all depend on W491, a potentially accessible extracellular residue that could become a target for therapeutic intervention.
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Benzoatos/farmacologia , Predisposição Genética para Doença , Hidrazinas/farmacologia , Mutação , Pirazóis/farmacologia , Receptores de Trombopoetina/agonistas , Receptores de Trombopoetina/genética , Trombocitemia Essencial/genética , Alelos , Substituição de Aminoácidos , Linhagem Celular , Estudos de Associação Genética , Humanos , Fenótipo , Transdução de Sinais/efeitos dos fármacos , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/metabolismoRESUMO
During the COVID-19 pandemic, rehearsal and concert activities of professional orchestras and choirs were severely restricted based on the assumption of particularly high infection risks associated with wind instruments and singing. Therefore, our primary objective was to determine the incidence of SARS-CoV-2 infections in orchestra and choir musicians compared to controls. We also assessed influenza, flu, upper respiratory tract infections, and course of illness. Musicians from professional orchestras and choirs and controls from 23 institutions throughout Germany were included in a prospective cohort study. Data were collected from October 2020 to June 2021 by weekly online surveys. A mixed-effects cox proportional hazards model was used to assess the effect of exposure by professional activity on SARS-CoV-2 infection. In 1,097 participants (46.7 years (SD 10.3); 46.8% female; 705 orchestra, 154 choir, and 238 control subjects) 40 SARS-CoV-2 infections occurred. Cases per person-years were 0.06 in orchestras, 0.11 in choirs, and 0.03 in controls. Hazard ratios compared to controls were 1.74 (95% CI 0.58 to 5.25, p = 0.320) for orchestra musicians and 2.97 (0.87 to 10.28, p = 0.087) for choir singers. Infection source was suspected predominantly in private contexts. Disease courses were mild to moderate. Other respiratory infections were reported in 6.1% of study weeks in orchestras, 10.1% in choirs, and 8.0% in controls. Sick leave days of total study days were 0.5, 2.1 and 1.3%, respectively. This epidemiologic study during the pandemic in professional musicians indicates no increased risk of SARS-CoV-2 infections in orchestra musicians and a trend towards increased risk in choir singers compared to controls. However, the exact routes of infection could not be validated. If appropriate hygiene concepts are adhered to, safe orchestra and choir activity appears possible in pandemic times.
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COVID-19 , Doenças Profissionais , Humanos , Feminino , Masculino , COVID-19/epidemiologia , Doenças Profissionais/epidemiologia , Pandemias , Estudos Prospectivos , SARS-CoV-2RESUMO
Implications for the academic and interpersonal development of children and adolescents underpin a global political consensus to maintain in-classroom teaching during the ongoing COVID-19 pandemic. In support of this aim, the WHO and UNICEF have called for schools around the globe to be made safer from the risk of COVID-19 transmission. Detailed guidance is needed on how this goal can be successfully implemented in a wide variety of educational settings in order to effectively mitigate impacts on the health of students, staff, their families, and society. This review provides a comprehensive synthesis of current scientific evidence and emerging standards in relation to the use of layered prevention strategies (involving masks, distancing, and ventilation), setting out the basis for their implementation in the school environment. In the presence of increasingly infectious SARS-Cov-2 variants, in-classroom teaching can only be safely maintained through a layered strategy combining multiple protective measures. The precise measures that are needed at any point in time depend upon a number of dynamic factors, including the specific threat-level posed by the circulating variant, the level of community infection, and the political acceptability of the resultant risk. By consistently implementing appropriate prophylaxis measures, evidence shows that the risk of infection from in-classroom teaching can be dramatically reduced. Current studies indicate that wearing high-quality masks and regular testing are amongst the most important measures in preventing infection transmission; whilst effective natural and mechanical ventilation systems have been shown to reduce infection risks in classrooms by over 80%.
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Poluição do Ar em Ambientes Fechados , COVID-19 , Criança , Adolescente , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Máscaras , Pandemias/prevenção & controle , Instituições AcadêmicasRESUMO
INTRODUCTION: Due to diagnostic challenges, normalization of symptoms and an overall lack of awareness among both patients and physicians, endometriosis is an underdiagnosed disease. This can result in delayed treatment and potentially worsening of the disease. Despite initiatives, such as patients' support organizations and specialized endometriosis referral centers, differences in awareness, socioeconomic factors and lifestyle, combined with varying distances to specialized referral centers, could result in regional differences in the degree of underdiagnosing. This study aims to explore temporal and regional variations in the incidence of endometriosis based on the Danish hospital discharge register, and shed light on the degree of underdiagnosing of endometriosis in Denmark. MATERIAL AND METHODS: This registry-based cohort study included all women aged 15-55 living in Denmark from 1990-2017. Participants were identified through the Danish Civil Registration system and endometriosis diagnoses received at a hospital were obtained from the Danish National Patient Registry. Incidence rates of diagnosed endometriosis were calculated for each year of the study period and for each municipality in Denmark. A Cox regression analysis, stratified by calendar time and adjusted for ethnic origin, household composition, highest educational level and family socioeconomic status, was performed to estimate the association between residence and likelihood of receiving a hospital-based diagnosis of endometriosis. RESULTS: The nationwide incidence rate of hospital-diagnosed endometriosis was 7.89 (95% confidence interval [CI] 7.80-7.99) per 10 000 person-years and the prevalence in 2017 was 1.63%. The results showed an overall increase in the incidence of diagnosed endometriosis of 46.8% (95% CI 32.9-62.2) during the study period and also displayed significant regional differences. After adjustments, women living in northern Jutland had the highest probability of receiving a hospital-based diagnosis of endometriosis (hazard ratio 1.13, 95% CI 1.09-1.18), whereas women living in northern Zealand had the lowest probability (hazard ratio 0.63, 95% CI 0.60-0.67) compared with eastern Jutland. These regional differences have become more evident over time. CONCLUSIONS: Our results reveal significant regional differences in the incidence of hospital-diagnosed endometriosis, suggesting that a significant number of women may be left behind without a diagnosis. Further studies are needed to assess the underlying reasons for the significant regional differences.