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INTRODUCTION: The immune receptor triggering receptor expressed on myeloid cells 2 (TREM2) is among the strongest genetic risk factors for Alzheimer's disease (AD) and is a therapeutic target. TREM2 multimers have been identified in crystallography and implicated in the efficacy of antibody therapeutics; however, the molecular basis for TREM2 multimerization remains poorly understood. METHODS: We used molecular dynamics simulations and binding energy analysis to determine the effects of AD-associated variants on TREM2 multimerization and validated with experimental results. RESULTS: TREM2 trimers remained stably bound, driven primarily by salt bridge between residues D87 and R76 at the interface of TREM2 units. This salt bridge was disrupted by the AD-associated variants R47H and R98W and nearly ablated by the D87N variant. This decreased binding among TREM2 multimers was validated with co-immunoprecipitation assays. DISCUSSION: This study uncovers a molecular basis for TREM2 forming stable trimers and unveils a novel mechanism by which TREM2 variants may increase AD risk by disrupting TREM2 oligomerization to impair TREM2 normal function. HIGHLIGHTS: Triggering receptor expressed on myeloid cells 2 (TREM2) multimerization could regulate TREM2 activation and function. D87-R76 salt bridges at the interface of TREM2 units drive the formation of stable TREM2 dimers and trimers. Alzheimer's disease (AD)-associated R47H and R98W variants disrupt the D87-R76 salt bridge. The AD-associated D87N variant leads to complete loss of the D87-R76 salt bridge.
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BACKGROUND: Male breast cancer (MBC) is a rare disease. Although several large-scale studies have investigated MBC patients in other countries, the features of MBC patients in China have not been fully explored. This study aims to explore the features of Chinese MBC patients comprehensively. METHODS: We retrospectively collected data of MBC patients from 36 centers in China. Overall survival (OS) was evaluated by the Kaplan-Meier method, log-rank test, and Cox regression analyses. Multivariate Cox analyses were used to identify independent prognostic factors of the patients. RESULTS: In total, 1119 patients were included. The mean age at diagnosis was 60.9 years, and a significant extension over time was observed (P < 0.001). The majority of the patients (89.1 %) received mastectomy. Sentinel lymph node biopsy was performed in 7.8 % of the patients diagnosed in 2009 or earlier, and this percentage increased significantly to 38.8 % in 2020 or later (P < 0.001). The five-year OS rate for the population was 85.5 % [95 % confidence interval (CI), 82.8 %-88.4 %]. Multivariate Cox analysis identified taxane-based [T-based, hazard ratio (HR) = 0.32, 95 % CI, 0.13 to 0.78, P = 0.012] and anthracycline plus taxane-based (A + T-based, HR = 0.47, 95 % CI, 0.23 to 0.96, P = 0.037) regimens as independent protective factors for OS. However, the anthracycline-based regimen showed no significance in outcome (P = 0.175). CONCLUSION: As the most extensive MBC study in China, we described the characteristics, treatment and prognosis of Chinese MBC population comprehensively. T-based and A + T-based regimens were protective factors for OS in these patients. More research is required for this population.
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Neoplasias da Mama Masculina , Mastectomia , Biópsia de Linfonodo Sentinela , Humanos , Neoplasias da Mama Masculina/patologia , Neoplasias da Mama Masculina/mortalidade , Neoplasias da Mama Masculina/terapia , Neoplasias da Mama Masculina/epidemiologia , Masculino , Pessoa de Meia-Idade , China/epidemiologia , Estudos Retrospectivos , Mastectomia/estatística & dados numéricos , Idoso , Biópsia de Linfonodo Sentinela/estatística & dados numéricos , Adulto , Prognóstico , Modelos de Riscos Proporcionais , Estimativa de Kaplan-Meier , Taxoides/uso terapêutico , Taxa de Sobrevida , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Antraciclinas/uso terapêutico , Idoso de 80 Anos ou maisRESUMO
Melatonin is widely present in Nature. It has pleiotropic activities, in part mediated by interactions with high-affinity G-protein-coupled melatonin type 1 and 2 (MT1 and MT2) receptors or under extreme conditions, e.g., ischemia/reperfusion. In pharmacological concentrations, it is given to counteract the massive damage caused by MT1- and MT2-independent mechanisms. The aryl hydrocarbon receptor (AhR) is a perfect candidate for mediating the latter effects because melatonin has structural similarity to its natural ligands, including tryptophan metabolites and indolic compounds. Using a cell-based Human AhR Reporter Assay System, we demonstrated that melatonin and its indolic and kynuric metabolites act as agonists on the AhR with EC50's between 10-4 and 10-6 M. This was further validated via the stimulation of the transcriptional activation of the CYP1A1 promoter. Furthermore, melatonin and its metabolites stimulated AhR translocation from the cytoplasm to the nucleus in human keratinocytes, as demonstrated by ImageStream II cytometry and Western blot (WB) analyses of cytoplasmic and nuclear fractions of human keratinocytes. These functional analyses are supported by in silico analyses. We also investigated the peroxisome proliferator-activated receptor (PPAR)γ as a potential target for melatonin and metabolites bioregulation. The binding studies using a TR-TFRET kit to assay the interaction of the ligand with the ligand-binding domain (LBD) of the PPARγ showed agonistic activities of melatonin, 6-hydroxymelatonin and N-acetyl-N-formyl-5-methoxykynuramine with EC50's in the 10-4 M range showing significantly lower affinities that those of rosiglitazone, e.g., a 10-8 M range. These interactions were substantiated by stimulation of the luciferase activity of the construct containing PPARE by melatonin and its metabolites at 10-4 M. As confirmed by the functional assays, binding mode predictions using a homology model of the AhR and a crystal structure of the PPARγ suggest that melatonin and its metabolites, including 6-hydroxymelatonin, 5-methoxytryptamine and N-acetyl-N-formyl-5-methoxykynuramine, are excellent candidates to act on the AhR and PPARγ with docking scores comparable to their corresponding natural ligands. Melatonin and its metabolites were modeled into the same ligand-binding pockets (LBDs) as their natural ligands. Thus, functional assays supported by molecular modeling have shown that melatonin and its indolic and kynuric metabolites can act as agonists on the AhR and they can interact with the PPARγ at high concentrations. This provides a mechanistic explanation for previously reported cytoprotective actions of melatonin and its metabolites that require high local concentrations of the ligands to reduce cellular damage under elevated oxidative stress conditions. It also identifies these compounds as therapeutic agents to be used at pharmacological doses in the prevention or therapy of skin diseases.
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Melatonina , Receptores de Hidrocarboneto Arílico , Humanos , Queratinócitos/metabolismo , Ligantes , Melatonina/metabolismo , PPAR gama/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismoRESUMO
Electronegative clusters (ENCs) made up of acidic residues and/or phosphorylation sites are the most abundant repetitive sequences in RNA-binding proteins. Previous studies have indicated that ENCs inhibit RNA binding for structured RNA-binding domains (RBDs). However, this is not the case for the unstructured RBD in histone pre-mRNA stem-loop binding protein (SLBP). The SLBP RBD contains 70 amino acids and is followed by a phosphorylatable ENC. ENC phosphorylation increases RNA-binding affinity of SLBP to the sub-picomolar range. In this study, we use NMR and molecular dynamics simulations to elucidate the mechanism for this tight binding. Our NMR data demonstrate that the ENC transiently folds apo SLBP into an RNA-bound resembling state. We find that in the RNA-bound state, the phosphorylated ENC interacts with the loop region opposite to the RNA-binding site. This allosteric interaction stabilizes the complex and therefore enhances RNA binding. To evaluate the generality of our findings, we graft an ENC onto endoribonuclease homolog 1's first double-stranded RNA-binding motif (DRBM1), an unstructured RBD that shares no homology with SLBP. We find that the engineered ENC increases the folded species of DRBM1 and inhibits RNA binding. On the contrary, introducing basic residues to DRBM1 makes the domain more unfolded, enhances RNA binding, and mitigates the inhibitory effect of the engineered ENC. In summary, our study suggests that ENCs promote folding of unstructured RNA-binding domains, and their effects on RNA binding depend on the electropositive charges on the RBD surface.
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Histonas , Proteínas Nucleares , Histonas/metabolismo , Proteínas Nucleares/química , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Sítios de Ligação , Ligação ProteicaRESUMO
BACKGROUND: Endocrine therapy (ET) and ET-based regimens are the preferred first-line treatment options for hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (HR+/HER2- MBC), while chemotherapy (CT) is commonly used in clinical practice. The aim of this study was to investigate the efficacy and clinical outcome of ET and CT as first-line treatment in Chinese patients with HR+/HER2- MBC. METHODS: Patients diagnosed with HR+/HER2-MBC between January 1st, 1996 and September 30th, 2018 were screened from the Chinese Society of Clinical Oncology Breast Cancer database. The initial and maintenance first-line treatment, progression-free survival (PFS), and overall survival (OS) were analyzed. RESULTS: Among the 1877 included patients, 1215 (64.7%) received CT and 662 (35.3%) received ET as initial first-line treatment. There were no statistically significant differences in PFS and OS between patients receiving ET and CT as initial first-line treatment in the total population (PFS: 12.0 vs. 11.0 months, P = 0.22; OS: 54.0 vs . 49.0 months, P =0.09) and propensity score matched population. For patients without disease progression after at least 3 months of initial therapy, maintenance ET following initial CT (CT-ET cohort, n = 449) and continuous schedule of ET (ET cohort, n = 527) had longer PFS than continuous schedule of CT (CT cohort, n = 406) in the total population (CT-ET cohort vs. CT cohort: 17.0 vs . 8.5 months; P <0.01; ET cohort vs . CT cohort: 14.0 vs . 8.5 months; P <0.01) and propensity score matched population. OS in the three cohorts yielded the same results as PFS. CONCLUSIONS: ET was associated with similar clinical outcome to CT as initial first-line treatment. For patients without disease progression after initial CT, switching to maintenance ET showed superiority in clinical outcome over continuous schedule of CT.
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Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/metabolismo , Receptor ErbB-2/metabolismo , Intervalo Livre de Progressão , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Progressão da Doença , Resultado do TratamentoRESUMO
OBJECTIVE: A growing number of studies have examined the 24-h rest-activity characteristics in relation to health outcomes. Up to now, few studies have paid attention to the role of rest-activity circadian rhythm in chronic respiratory diseases (CRDs); therefore, to fill this gap, our study innovatively explored the association of rest-activity circadian rhythm indices with CRDs. METHODS: A total of 7412 participants from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 were included in this study. The rest-activity circadian rhythm indices were calculated using accelerometer data and were divided into quartiles to perform logistic regression. RESULTS: Participants in the highest quartile of Relative amplitude (RA) had a lower prevalence of emphysema, chronic bronchitis and asthma, compared to those in the lowest quartile. Participants in the highest quartile of Intradaily variability (IV) was associated with a higher prevalence of emphysema relative to those in the lowest quartile. Compared to those in the lowest quartile, participants in the highest quartile of the average activity of the most active continuous 10-h period (M10) had a lower prevalence of emphysema. Additionally, compared to those in the lowest quartile of the average activity of the least active continuous 5-h period (L5) and L5 start time, participants in the highest quartile had a higher prevalence of asthma. CONCLUSIONS: This study demonstrated that in general US adult population, disrupted rest-activity circadian rhythm was associated with a higher prevalence of CRDs.
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Asma , Enfisema , Enfisema Pulmonar , Transtornos Respiratórios , Adulto , Humanos , Sono , Inquéritos Nutricionais , Atividade Motora , Ritmo Circadiano , Asma/epidemiologia , ActigrafiaRESUMO
Background: Antibody-drug conjugate (ADC) is an emerging therapy that bestows advanced breast tumors with encouraging clinical activity and manageable toxicity; however, the outcomes of phase 2/3 randomized controlled trials (RCTs) are heterogeneous. Our study aims to assess the clinical utilities [i.e., objective response rate (ORR), clinical benefit rate (CBR), progression-free survival (PFS), overall survival (OS)], and treatment-related adverse events (AEs) of ADC monotherapy (defined as the study cohort) versus the therapy of physician's choice (TPC) (defined as the control cohort) in participants with advanced breast tumors. Methods: We conducted a computerized retrieval to identify RCTs from MEDLINE, Web of Science, Cochrane Library, Embase databases, and ClinicalTrials.gov until April 4th, 2023. Screening, data extraction, and quality assessment were performed in duplicate. Results: A total of 10 RCTs were involved, with 5,089 unique patients. A binary random-effect model Mantel-Haenszel method was employed to pool data due to the considerable heterogeneity. The primary outcome measure was odds ratio (OR) with the corresponding 95% confidential interval (CI) of ORR and CBR. The secondary outcome measure represented hazard ratio (HR) of PFS and OS and OR of the frequency of any grade/grade ≥3 AEs. The pooled results showed an insignificant difference of ORR (OR =1.64; 95% CI: 0.86-3.13; P=0.136) and CBR (OR =1.43; 95% CI: 0.89-2.31; P=0.142) in the study cohort than the control cohort. The pooled effect on PFS (HR =0.62; 95% CI: 0.50-0.74; P<0.001) and on OS (HR =0.70; 95% CI: 0.57-0.83; P<0.001) both indicated a significant superiority of the study cohort. The frequency of any grade AEs (OR =1.03; 95% CI: 0.75-1.41; P=0.849) and that of grade ≥3 AEs (OR =0.83; 95% CI: 0.57-1.21; P=0.342) were both observed a nonsignificant difference between the cohorts. These domains, i.e., allocation concealment, blinding of participants and personnel, and blinding of outcome assessment, had the high risk of bias over 50%. Conclusions: Compared to physician's choice, ADC monotherapy overall confirms a considerable refinement in survival benefits plus a similar safety profile in advanced breast tumors.
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Dietary carbohydrate consumption was related to cognitive function. Whereas, there was no study investigate the association of dietary carbohydrate consumption with cognitive function modification by daily fasting duration. This study aims to examine the association between dietary carbohydrate consumption and cognitive function among participants with different daily fasting duration. In this cross-sectional study, 2485 adults aged over 60 years from the nationally representative data of the National Health and Nutrition Examination Survey (NHANES, 2011-2014) were enrolled. Percentage energy from carbohydrates was present in both quartiles and continuous forms. Daily fasting duration = 24 - (timing for dinner - breakfast). Cognitive function was assessed by the Consortium to Establish a Registry for Alzheimer's Disease Word List Learning (CERAD-WL), CERAD Word List Delayed Recall (CERAD-DR), Animal Fluency (AF), and Digit Symbol Substitution (DSST) Test. Multiple logistic regression and linear regression models were developed to examine the association of dietary carbohydrates with cognitive function among participants with different daily fasting duration. Restricted cubic spline models were also applied. Compared with the lowest quartile of percentage energy from carbohydrates, the highest quartile had higher ORs of poor cognitive performance among total participants [(ORCERAD-WL 1.84 95% CI 1.25-2.71); (ORCERAD-DR 1.45 95% CI 1.10-1.91)] and participants with daily fasting duration fewer than 16 h [(ORCERAD-WL 2.14 95% CI 1.29-3.55); (ORCERAD-DR 1.51 95% CI 1.05-2.17)] but not in participants with daily fasting duration of more than 16 h. Further, the negative associations between percentage energy from carbohydrates and CERAD-WL score were still significant in addition to participants whose daily fasting duration was more than 16 h. Additionally, dose-response associations were detected between dietary carbohydrates and cognitive decline, while "U" curves were observed among participants whose daily fasting duration was more than 16 h. This study indicated that dietary carbohydrates consumption was associated with poor cognitive performance, but not in participants whose daily fasting duration was more than 16 h among US older adults. The current analysis provides evidence that a longer daily fasting duration may improve the harmful effect of dietary carbohydrates on cognitive function.
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CYP11A1 and CYP27A1 hydroxylate tachysterol3 , a photoproduct of previtamin D3 , producing 20S-hydroxytachysterol3 [20S(OH)T3 ] and 25(OH)T3 , respectively. Both metabolites were detected in the human epidermis and serum. Tachysterol3 was also detected in human serum at a concentration of 7.3 ± 2.5 ng/ml. 20S(OH)T3 and 25(OH)T3 inhibited the proliferation of epidermal keratinocytes and dermal fibroblasts and stimulated the expression of differentiation and anti-oxidative genes in keratinocytes in a similar manner to 1,25-dihydroxyvitamin D3 [1,25(OH)2 D3 ]. They acted on the vitamin D receptor (VDR) as demonstrated by image flow cytometry and the translocation of VDR coupled GFP from the cytoplasm to the nucleus of melanoma cells, as well as by the stimulation of CYP24A1 expression. Functional studies using a human aryl hydrocarbon receptor (AhR) reporter assay system revealed marked activation of AhR by 20S(OH)T3 , a smaller effect by 25(OH)T3 , and a minimal effect for their precursor, tachysterol3 . Tachysterol3 hydroxyderivatives showed high-affinity binding to the ligan-binding domain (LBD) of the liver X receptor (LXR) α and ß, and the peroxisome proliferator-activated receptor γ (PPARγ) in LanthaScreen TR-FRET coactivator assays. Molecular docking using crystal structures of the LBDs of VDR, AhR, LXRs, and PPARγ revealed high docking scores for 20S(OH)T3 and 25(OH)T3 , comparable to their natural ligands. The scores for the non-genomic-binding site of the VDR were very low indicating a lack of interaction with tachysterol3 ligands. Our identification of endogenous production of 20S(OH)T3 and 25(OH)T3 that are biologically active and interact with VDR, AhR, LXRs, and PPARγ, provides a new understanding of the biological function of tachysterol3 .
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Colecalciferol , PPAR gama , Receptores de Calcitriol , Ativação Metabólica , Colecalciferol/análogos & derivados , Colecalciferol/metabolismo , Colecalciferol/farmacocinética , Humanos , Receptores X do Fígado/metabolismo , Simulação de Acoplamento Molecular , PPAR gama/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Calcitriol/metabolismoRESUMO
To better understand the molecular and structural basis underlying the interaction of vitamin D3 hydroxyderivatives with AhR, molecular simulation was used to probe the binding of 1,20(OH)2D3, 1,25(OH)2D3, 20,23(OH)2D3 and 20(OH)D3 to AhR. qPCR showed that vitamin D3 derivatives stimulate expression of cyp1A1 and cyp1B1 genes that are downstream targets of AhR signaling. These secosteroids stimulated the translocation of the AhR to the nucleus, as measured by flow cytometry and western blotting. Molecular dynamics simulations were used to model the binding of vitamin D3 derivatives to AhR to examine their influence on the structure, conformation and dynamics of the AhR ligand binding domain (LBD). Binding thermodynamics, conformation, secondary structure, dynamical motion and electrostatic potential of AhR were analyzed. The molecular docking scores and binding free energy were all favorable for the binding of D3 derivatives to the AhR. These established ligands and the D3 derivatives are predicted to have different patterns of hydrogen bond formation with the AhR, and varied residue conformational fluctuations and dynamical motion for the LBD. These changes could alter the shape, size and electrostatic potential distribution of the ligand binding pocket, contributing to the different binding affinities of AhR for the natural ligands and D3 derivatives.
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Colecalciferol , Receptores de Hidrocarboneto Arílico , Colecalciferol/química , Ligantes , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Receptores de Hidrocarboneto Arílico/química , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismoRESUMO
BACKGROUND: Despite extensive investigations on photothermal therapy, the clinical application is restricted due to poor stability, low therapeutic efficacy of photothermal therapy agents and its affinity loss in the multistep synthesis of delivery carriers. To address this, we designed an IR792-MCN@ZIF-8-PD-L1 siRNA (IM@ZP) nanoparticle drug delivery system. IM@ZP was prepared by in situ synthesis and physical adsorption, followed by characterization. Photothermal conversion ability of IM@ZP was assessed by irradiation of near-infrared (NIR) laser, followed by analysis of its effect on 4T1 cell viability, maturation of dendritic cells (DCs) and the secretion of related cytokines in vitro, and the changes of tumor infiltrating T cells and natural killer (NK) cells in vivo. Subcutaneous 4T1 tumor-bearing mouse and lung metastasis models were established to investigate the role of IM@ZP in killing tumor and inhibiting metastasis in vivo. RESULTS: IM@ZP was uniform nanoparticles of 81.67 nm with the characteristic UV absorption peak of IR792, and could effectively adsorb PD-L1 siRNA. Under the irradiation of 808 nm laser, IM@ZP exhibited excellent photothermal performance. IM@ZP could be efficiently uptaken by 4T1 cells, and had high transfection efficiency of PD-L1 siRNA. Upon NIR laser irradiation, IM@ZP effectively killed 4T1 cells, upregulated HSP70 expression, induced DC maturation and increased secretion of TNF-α and IL-6 in vitro. Moreover, in vivo experimental results revealed that IM@ZP enhanced photothermal immunotherapy as shown by promoted tumor infiltrating CD8 + and CD4 + T cells and NK cells, and inhibited tumor growth and lung metastasis. CONCLUSION: Together, biocompatible IM@ZP nanoparticles result in high photothermal immunotherapy efficiency and may have a great potential as a delivery system for sustained cancer therapy.
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Nanopartículas , Neoplasias de Mama Triplo Negativas , Animais , Antígeno B7-H1 , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Imunoterapia , Lasers , Camundongos , Fototerapia/métodos , RNA Interferente Pequeno/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológicoRESUMO
New and more efficient routes of chemical synthesis of vitamin D3 (D3) hydroxy (OH) metabolites, including 20S(OH)D3, 20S,23S(OH)2D3 and 20S,25(OH)2D3, that are endogenously produced in the human body by CYP11A1, and of 20S,23R(OH)2D3 were established. The biological evaluation showed that these compounds exhibited similar properties to each other regarding inhibition of cell proliferation and induction of cell differentiation but with subtle and quantitative differences. They showed both overlapping and differential effects on T-cell immune activity. They also showed similar interactions with nuclear receptors with all secosteroids activating vitamin D, liver X, retinoic acid orphan and aryl hydrocarbon receptors in functional assays and also as indicated by molecular modeling. They functioned as substrates for CYP27B1 with enzymatic activity being the highest towards 20S,25(OH)2D3 and the lowest towards 20S(OH)D3. In conclusion, defining new routes for large scale synthesis of endogenously produced D3-hydroxy derivatives by pathways initiated by CYP11A1 opens an exciting era to analyze their common and differential activities in vivo, particularly on the immune system and inflammatory diseases.
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Enzima de Clivagem da Cadeia Lateral do Colesterol , Vitaminas , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Humanos , Receptores de Calcitriol/metabolismo , Receptores Citoplasmáticos e Nucleares , Vitamina D/metabolismoRESUMO
BACKGROUND: Patients with HER2-positive metastatic breast cancer have a high risk of developing brain metastases. Efficacious treatment options are scarce. We investigated the activity and safety of pyrotinib plus capecitabine in patients with HER2-positive metastatic breast cancer and brain metastases. METHODS: We did a multicentre, single-arm, two-cohort, phase 2 trial in eight tertiary hospitals in China. Patients aged 18 years or older who had radiotherapy-naive HER2-positive brain metastases (cohort A) or progressive disease after radiotherapy (cohort B), with an Eastern Cooperative Oncology Group performance status of 0-2, received pyrotinib 400 mg orally once daily, and capecitabine 1000 mg/m2 orally twice daily for 14 days, followed by 7 days off every 3 weeks until disease progression or unacceptable toxicity. The primary endpoint was confirmed intracranial objective response rate by investigator assessment according to the Response Evaluation Criteria In Solid Tumours (version 1.1). Activity and safety were analysed in patients with at least one dose of study drug. The study is ongoing, but recruitment is complete. The study is registered with ClinicalTrials.gov, NCT03691051. FINDINGS: Between Jan 29, 2019, and July 10, 2020, we enrolled 78 women: 51 (86%) of 59 patients in cohort A and 18 (95%) of 19 patients in cohort B had previous exposure to trastuzumab. Median follow-up duration was 15·7 months (IQR 9·7-19·0). The intracranial objective response rate was 74·6% (95% CI 61·6-85·0; 44 of 59 patients) in cohort A and 42·1% (20·3-66·5; eight of 19 patients) in cohort B. The most common grade 3 or worse treatment-emergent adverse event was diarrhoea (14 [24%] in cohort A and four [21%] in cohort B). Two (3%) patients in cohort A and three (16%) in cohort B had treatment-related serious adverse events. No treatment-related deaths occurred. INTERPRETATION: To our knowledge, this is the first prospective study showing the activity and safety of pyrotinib plus capecitabine in patients with HER2-positive breast cancer and brain metastases, especially in radiotherapy-naive population. This combination deserves further validation in a randomised, controlled trial. FUNDING: National Cancer Centre Climbing Foundation Key Project of China, Jiangsu Hengrui Pharmaceuticals. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.
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Neoplasias Encefálicas , Neoplasias da Mama , Acrilamidas , Aminoquinolinas , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Capecitabina , Feminino , Humanos , Masculino , Estudos Prospectivos , Receptor ErbB-2/metabolismoRESUMO
The epidemiologic correlation between the poor prognosis of SARS-CoV-2 infection and vitamin D deficiency has been observed worldwide, however, their molecular mechanisms are not fully understood. In this study, we used combined molecular docking, molecular dynamics simulations and binding free energy analyses to investigate the potentials of vitamin D3 and its hydroxyderivatives as TMPRSS2 inhibitor and to inhibit the SARS-CoV-2 receptor binding domain (RBD) binding to angiotensin-converting enzyme 2 (ACE2), as well as to unveil molecular and structural basis of 1,25(OH)2D3 capability to inhibit ACE2 and SARS-CoV-2 RBD interactions. The results show that vitamin D3 and its hydroxyderivatives are favorable to bind active site of TMPRSS2 and the binding site(s) between ACE2 and SARS-CoV2-RBD, which indicate that vitamin D3 and its biologically active hydroxyderivatives can serve as TMPRSS2 inhibitor and can inhibit ACE2 binding of SARS-CoV-2 RBD to prevent SARS-CoV-2 entry. Interaction of 1,25(OH)2D3 with SARS-CoV-2 RBD and ACE2 resulted in the conformation and dynamical motion changes of the binding surfaces between SARS-CoV-2 RBD and ACE2 to interrupt the binding of SARS-CoV-2 RBD with ACE2. The interaction of 1,25(OH)2D3 with TMPRSS2 also caused the conformational and dynamical motion changes of TMPRSS2, which could affect TMPRSS2 to prime SARS-CoV-2 spike proteins. Our results propose that vitamin D3 and its biologically active hydroxyderivatives are promising drugs or adjuvants in the treatment of COVID-19. Communicated by Ramaswamy H. Sarma.
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COVID-19 , Humanos , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2 , Colecalciferol/farmacologia , Simulação de Acoplamento Molecular , RNA Viral , Simulação de Dinâmica Molecular , Ligação ProteicaRESUMO
BACKGROUND: Fulvestrant 500 mg monotherapy is recommended as the first-line endocrine treatment in postmenopausal women with hormone receptor-positive metastatic breast cancer (MBC). It is also used in MBC maintenance treatment. However, few studies have compared the efficacy of fulvestrant during the initial treatment with that during maintenance treatment. PATIENTS AND METHODS: MBC patients who were treated with fulvestrant either as initial therapy for metastatic disease or after progression following one line of chemotherapy between January 2016 and December 2017 were identified from the database of the Affiliated Hospital of Qingdao University. The primary end point was progression-free survival (PFS). RESULTS: The study included 135 MBC patients who were treated with fulvestrant; 116 patients who received fulvestrant as first-line treatment were divided into 2 groups: the no-chemotherapy treatment (NCT) group received fulvestrant as initial therapy during disease progression, and the chemotherapy treatment (CT) group received fulvestrant as maintenance following disease stabilization or response to previous chemotherapy. The median PFS was 16 months in NCT patients and 8 months in the CT group. Patients who had a longer disease-free survival, no visceral metastasis and one metastasis site, benefited from fulvestrant as first-line treatment during disease progression. Patients with 2 or more metastasis sites benefited from chemotherapy as first-line treatment and fulvestrant as maintenance treatment. CONCLUSIONS: Fulvestrant monotherapy showed good clinical activity and safety in patients with MBC who were treated upon disease progression and in those receiving maintenance therapy.
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BACKGROUND: Although endocrine therapy (ET) is the preferred option for hormone receptor-positive HER2-negative metastatic breast cancer (HR+/HER2- MBC), chemotherapy (CT) is still commonly used. The objective of this real-world study was to present the actual choice of first-line treatment for patients with HR+/HER2- MBC and evaluate the consistency with guidelines in China. METHODS: Patients with HR+/HER2- MBC between 1996 and September 2018 were identified from of the database of Chinese Society of Clinical Oncology Breast Cancer (CSCO BC). The statistical description was conducted to present the first-line treatment. Factors influencing the prescription of ET or CT were obtained using univariate and multivariate analysis. The consistency of the actual treatment with the guideline of Chinese Society of Clinical Oncology Breast Cancer (CSCO BC guideline) was evaluated. RESULTS: Of 1,877 patients, 662 (35.3%) received ET, and 1,215 (64.7%) received CT. ET proportion was only 25.4% in 1996-2005 and gradually increased to 44.6% in 2016-2018. Aromatase inhibitors (69% of ET) and taxane-based regimens (66% of CT) were the most commonly used ET and CT, respectively. Univariate and multivariate analysis showed that patients with age ≥60, distant relapse-free interval (DRFI) ≥24 months, ER+/PR+, bone metastasis only, or progression on (neo)adjuvant ET were preferably chosen for ET as first-line treatment. Factors associated with preferring CT were de novo stage IV, liver or lung metastasis. 17.2% of patients (322 cases) who had neither visceral metastasis nor progression on (neo)adjuvant ET wrongly received CT instead of ET, which is inconsistent with CSCO BC guideline. More than half of patients receiving CT discontinued their initial treatment due to adverse events and other non-disease progression reasons. CONCLUSIONS: Although high proportion of HR+/HER2- MBC patients received CT as first-line treatment in China, it is gratifying to see that the proportion of patients receiving ET has gradually increased. Our study revealed that 17.2% of patients were over-treated according to CSCO BC guideline, which may provide data to promote guideline adherence. The clinical application for ET should be appropriately expanded in first-line treatment, especially for patients without visceral disease and proof of endocrine resistance.
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Hepatic gluconeogenesis is essential for glucose homeostasis and also a therapeutic target for type 2 diabetes, but its mechanism is incompletely understood. Here, we report that Sam68, an RNA-binding adaptor protein and Src kinase substrate, is a novel regulator of hepatic gluconeogenesis. Both global and hepatic deletions of Sam68 significantly reduce blood glucose levels and the glucagon-induced expression of gluconeogenic genes. Protein, but not mRNA, levels of CRTC2, a crucial transcriptional regulator of gluconeogenesis, are >50% lower in Sam68-deficient hepatocytes than in wild-type hepatocytes. Sam68 interacts with CRTC2 and reduces CRTC2 ubiquitination. However, truncated mutants of Sam68 that lack the C- (Sam68ΔC) or N-terminal (Sam68ΔN) domains fails to bind CRTC2 or to stabilize CRTC2 protein, respectively, and transgenic Sam68ΔN mice recapitulate the blood-glucose and gluconeogenesis profile of Sam68-deficient mice. Hepatic Sam68 expression is also upregulated in patients with diabetes and in two diabetic mouse models, while hepatocyte-specific Sam68 deficiencies alleviate diabetic hyperglycemia and improves insulin sensitivity in mice. Thus, our results identify a role for Sam68 in hepatic gluconeogenesis, and Sam68 may represent a therapeutic target for diabetes.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Gluconeogênese/fisiologia , Fígado/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Glicemia/metabolismo , Proteínas de Ligação a DNA , Diabetes Mellitus Tipo 2/metabolismo , Regulação da Expressão Gênica , Glucagon/metabolismo , Gluconeogênese/genética , Glucose/metabolismo , Hepatócitos/metabolismo , Homeostase , Humanos , Hiperglicemia , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética , Regulação para CimaRESUMO
The interactions of derivatives of lumisterol (L3) and vitamin D3 (D3) with liver X receptors (LXRs) were investigated. Molecular docking using crystal structures of the ligand binding domains (LBDs) of LXRα and ß revealed high docking scores for L3 and D3 hydroxymetabolites, similar to those of the natural ligands, predicting good binding to the receptor. RNA sequencing of murine dermal fibroblasts stimulated with D3-hydroxyderivatives revealed LXR as the second nuclear receptor pathway for several D3-hydroxyderivatives, including 1,25(OH)2D3. This was validated by their induction of genes downstream of LXR. L3 and D3-derivatives activated an LXR-response element (LXRE)-driven reporter in CHO cells and human keratinocytes, and by enhanced expression of LXR target genes. L3 and D3 derivatives showed high affinity binding to the LBD of the LXRα and ß in LanthaScreen TR-FRET LXRα and ß coactivator assays. The majority of metabolites functioned as LXRα/ß agonists; however, 1,20,25(OH)3D3, 1,25(OH)2D3, 1,20(OH)2D3 and 25(OH)D3 acted as inverse agonists of LXRα, but as agonists of LXRß. Molecular dynamics simulations for the selected compounds, including 1,25(OH)2D3, 1,20(OH)2D3, 25(OH)D3, 20(OH)D3, 20(OH)L3 and 20,22(OH)2L3, showed different but overlapping interactions with LXRs. Identification of D3 and L3 derivatives as ligands for LXRs suggests a new mechanism of action for these compounds.
Assuntos
Ergosterol/farmacologia , Receptores X do Fígado/metabolismo , Vitamina D/farmacologia , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Animais Recém-Nascidos , Células CHO , Calcitriol , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Biologia Computacional , Cricetulus , Derme/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Ligação de Hidrogênio , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Ligantes , Receptores X do Fígado/química , Receptores X do Fígado/genética , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Secundária de Proteína , Transporte Proteico/efeitos dos fármacos , RNA-Seq , Eletricidade Estática , TermodinâmicaRESUMO
PURPOSE: To evaluate the influence of FLT3-ITD mutations on the treatment response and long-term survival of newly-diagnosed patients with acute promyelocytic leukemia (APL) treated with all-trans retinoic acid and arsenic trioxide. METHODS: The long-term survival of 90 newly-diagnosed APL patients (age range 12-75 years) was retrospectively analyzed.The FLT3-ITD mutation rate was assayed by polymerase chain reaction (PCR) amplification and sequencing analysis. Its impact on the treatment response, event-free survival(EFS), or overall survival(OS) was investigated in patients with and without the mutations. RESULTS: The FLT3-ITD mutation rate in newly-diagnosed APL patients was 20% (18/90). The white blood cell (WBC) count at diagnosis in patients with mutations was significantly higher than that in patients without mutations while the FLT3-ITD mutation rate was higher in the high-risk group than in the low/intermediate-risk group. Patients with mutations had a significantly higher early death (ED) rate (16.67% vs 1.39%) for those lacking the mutation (P =0.024). However, the complete remission (CR) and differentiation syndrome (DS) rates in the two groups were similar. Kaplan Meier analysis for EFS and OS at five years showed a significant difference between the patients stratified by FLT3-ITD mutation status (log-rank P =0.010 and P =0.009, respectively). CONCLUSION: FLT3-ITD mutations can be related to high peripheral WBC counts in APL patients. APL patients with mutations displayed a higher ED rate compared to those without mutations. Patients carrying mutations had reduced five-year EFS and OS rates. Thus, reducing the overall death rate during induction treatment might be an effective way to improve the prognosis of patients with FLT3-ITD mutations.
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AIMS: Cell surface binding immunoglobin protein (csBiP) is predicted to be susceptible to SARS-CoV-2 binding. With a substrate-binding domain (SBD) that binds to polypeptides and a nucleotide-binding domain (NBD) that can initiate extrinsic caspase-dependent apoptosis, csBiP may be a promising therapeutic target for COVID-19. This study aims to identify FDA-approved drugs that can neutralize viral binding and prevent viral replication by targeting the functional domains of csBiP. METHODS: In silico screening of 1999 FDA-approved drugs against the functional domains of BiP were performed using three molecular docking programs to avoid bias from individual docking programs. Top ligands were selected by averaging the ligand rankings from three programs. Interactions between top ligands and functional domains of BiP were analyzed. KEY FINDINGS: The top 10 SBD-binding candidates are velpatasvir, irinotecan, netupitant, lapatinib, doramectin, conivaptan, fenoverine, duvelisib, irbesartan, and pazopanib. The top 10 NBD-binding candidates are nilotinib, eltrombopag, grapiprant, topotecan, acetohexamide, vemurafenib, paritaprevir, pixantrone, azosemide, and piperaquine-phosphate. Among them, Velpatasvir and paritaprevir are antiviral agents that target the protease of hepatitis C virus. Netupitant is an anti-inflammatory drug that inhibits neurokinin-1 receptor, which contributes to acute inflammation. Grapiprant is an anti-inflammatory drug that inhibits the prostaglandin E2 receptor protein subtype 4, which is expressed on immune cells and triggers inflammation. These predicted SBD-binding drugs could disrupt SARS-CoV-2 binding to csBiP, and NBD-binding drugs may falter viral attachment and replication by locking the SBD in closed conformation and triggering apoptosis in infected cells. SIGNIFICANCE: csBiP appears to be a novel therapeutic target against COVID-19 by preventing viral attachment and replication. These identified drugs could be repurposed to treat COVID-19 patients.