RESUMO
The ecology and genetic diversity of the model yeast Saccharomyces cerevisiae before human domestication remain poorly understood. Taiwan is regarded as part of this yeast's geographic birthplace, where the most divergent natural lineage was discovered. Here, we extensively sampled the broadleaf forests across this continental island to probe the ancestral species' diversity. We found that S. cerevisiae is distributed ubiquitously at low abundance in the forests. Whole-genome sequencing of 121 isolates revealed nine distinct lineages that diverged from Asian lineages during the Pleistocene, when a transient continental shelf land bridge connected Taiwan to other major landmasses. Three lineages are endemic to Taiwan and six are widespread in Asia, making this region a focal biodiversity hotspot. Both ancient and recent admixture events were detected between the natural lineages, and a genetic ancestry component associated with isolates from fruits was detected in most admixed isolates. Collectively, Taiwanese isolates harbor genetic diversity comparable to that of the whole Asia continent, and different lineages have coexisted at a fine spatial scale even on the same tree. Patterns of variations within each lineage revealed that S. cerevisiae is highly clonal and predominantly reproduces asexually in nature. We identified different selection patterns shaping the coding sequences of natural lineages and found fewer gene family expansion and contractions that contrast with domesticated lineages. This study establishes that S. cerevisiae has rich natural diversity sheltered from human influences, making it a powerful model system in microbial ecology.
Assuntos
Biodiversidade , Saccharomyces cerevisiae , Ásia , Humanos , Filogenia , Saccharomyces cerevisiae/genética , Taiwan , Sequenciamento Completo do GenomaRESUMO
Tissue wounding induces cutaneous sensory axon regeneration via hydrogen peroxide (H2O2) that is produced by the epithelial NADPH oxidase, Duox1. Sciatic nerve injury instead induces axon regeneration through neuronal uptake of the NADPH oxidase, Nox2, from macrophages. We therefore reasoned that the tissue environment in which axons are damaged stimulates distinct regenerative mechanisms. Here, we show that cutaneous axon regeneration induced by tissue wounding depends on both neuronal and keratinocyte-specific mechanisms involving H2O2 signaling. Genetic depletion of H2O2 in sensory neurons abolishes axon regeneration, whereas keratinocyte-specific H2O2 depletion promotes axonal repulsion, a phenotype mirrored in duox1 mutants. Intriguingly, cyba mutants, deficient in the essential Nox subunit, p22Phox, retain limited axon regenerative capacity but display delayed Wallerian degeneration and axonal fusion, observed so far only in invertebrates. We further show that keratinocyte-specific oxidation of the epidermal growth factor receptor (EGFR) at a conserved cysteine thiol (C797) serves as an attractive cue for regenerating axons, leading to EGFR-dependent localized epidermal matrix remodeling via the matrix-metalloproteinase, MMP-13. Therefore, wound-induced cutaneous axon de- and regeneration depend on the coordinated functions of NADPH oxidases mediating distinct processes following injury.
Assuntos
Axônios , Peróxido de Hidrogênio , NADPH Oxidases , Regeneração Nervosa , Cicatrização , Proteínas de Peixe-Zebra , Animais , Axônios/fisiologia , Peróxido de Hidrogênio/metabolismo , Queratinócitos/fisiologia , NADPH Oxidases/genética , NADPH Oxidases/fisiologia , Regeneração Nervosa/genética , Células Receptoras Sensoriais/fisiologia , Cicatrização/genética , Cicatrização/fisiologia , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/fisiologiaRESUMO
Polycystic kidney disease (PKD) is a ciliopathy characterized by fluid-filled epithelial cysts in the kidney. Although it is well established that the primary cilium is essential for hedgehog (HH) signaling and HH signaling is abnormally activated in multiple PKD models, the mechanism and function of HH activation in PKD pathogenesis remain incompletely understood. Here we used a transgenic HH reporter mouse line to identify the target tissue of HH signaling in Arl13f/f;Ksp-Cre mutant kidney, in which the cilia biogenesis gene Arl13b is specifically deleted in epithelial cells of the distal nephron. In addition, we used a co-culture system to dissect cross-talk between epithelial and mesenchymal cells in the absence of expanding cysts. Finally, we treated Arl13bf/f;Ksp-Cre mice with the GLI inhibitor GANT61 and analyzed its impact on PKD progression in this model. We found that deletion of Arl13b in epithelial cells in the mouse kidney, in vivo, led to non-cell-autonomous activation of the HH pathway in the interstitium. In vitro, when co-cultured with mesenchymal cells, Arl13b-/- epithelial cells produced more sonic hedgehog in comparison to cells expressing Arl13b. Reciprocally, HH signaling was activated in mesenchymal cells co-cultured with Arl13b-/- epithelial cells. Finally, whole body inhibition of the HH pathway by GANT61 reduced the number of proliferating cells, inhibited cyst progression and fibrosis and preserved kidney function in Arl13bf/f;Ksp-Cre mice. Our results reveal non-cell-autonomous activation of HH signaling in the interstitium of the Arl13bf/f;Ksp-Cre kidney and suggest that abnormal activation of the HH pathway contributes to disease progression.
Assuntos
Ciliopatias , Cistos , Doenças Renais Císticas , Camundongos , Animais , Proteínas Hedgehog/metabolismo , Doenças Renais Císticas/genética , Modelos Animais de Doenças , Camundongos Transgênicos , Ciliopatias/genética , Progressão da DoençaRESUMO
BACKGROUND: A specific type of prostate cancer (PC) that exhibits neuroendocrine (NE) differentiation is known as NEPC. NEPC has little to no response to androgen deprivation therapy and is associated with the development of metastatic castration-resistant PC (CRPC), which has an extremely poor prognosis. Our understanding of genetic drivers and activated pathways in NEPC is limited, which hinders precision medicine approaches. L1 cell adhesion molecule (L1CAM) is known to play an oncogenic role in metastatic cancers, including CRPC. However, the impact of L1CAM on NEPC progression remains elusive. METHODS: L1CAM expression level was investigated using public gene expression databases of PC cohorts and patient-derived xenograft models. L1CAM knockdown was performed in different PC cells to study in vitro cell functions. A subline of CRPC cell line CWR22Rv1 was established after long-term exposure to abiraterone to induce NE differentiation. The androgen receptor-negative cell line PC3 was cultured under the tumor sphere-forming condition to enrich cancer stemness features. Several oxidative stress inducers were tested on PC cells to observe L1CAM-mediated gene expression and cell death. RESULTS: L1CAM expression was remarkably high in NEPC compared to CRPC or adenocarcinoma tumors. L1CAM was also correlated with NE marker expressions and associated with the adenocarcinoma-to-NEPC progression in gene expression databases and CRPC cells with NE differentiation. L1CAM also promoted cancer stemness and NE phenotypes in PC3 cells under cancer stemness enrichment. L1CAM was also identified as a reactive oxygen species-induced gene, by which L1CAM counteracted CRPC cell death triggered by ionizing radiation. CONCLUSIONS: Our results unveiled a new role of L1CAM in the acquisition of the NE phenotype in PC, contributing to the NE differentiation-related therapeutic resistance of CRPC.
RESUMO
BACKGROUND: Cyclic nucleotides are critical mediators of cellular signalling in glioblastoma. However, the clinical relevance and mechanisms of regulating cyclic nucleotides in glioblastoma progression and recurrence have yet to be thoroughly explored. METHODS: In silico, mRNA, and protein level analyses identified the primary regulator of cyclic nucleotides in recurrent human glioblastoma. Lentiviral and pharmacological manipulations examined the functional impact of cyclic nucleotide signalling in human glioma cell lines and primary glioblastoma cells. An orthotopic xenograft mice model coupled with aspirin hydrogels verified the in vivo outcome of targeting cyclic nucleotide signalling. RESULTS: Elevated intracellular levels of cGMP, instead of cAMP, due to a lower substrate efflux from ATP-binding cassette sub-family C member 4 (ABCC4) is engaged in the recurrence of glioblastoma. ABCC4 gene expression is negatively associated with recurrence and overall survival outcomes in glioblastoma specimens. ABCC4 loss-of-function activates cGMP-PKG signalling, promoting malignancy in glioblastoma cells and xenografts. Hydrogels loaded with aspirin, inhibiting glioblastoma progression partly by upregulating ABCC4 expressions, augment the efficacy of standard-of-care therapies in orthotopic glioblastoma xenografts. CONCLUSION: ABCC4, repressing the cGMP-PKG signalling pathway, is a tumour suppressor in glioblastoma progression and recurrence. Aspirin hydrogels impede glioblastoma progression through ABCC4 restoration and constitute a viable translational approach.
Assuntos
AMP Cíclico , Glioblastoma , Humanos , Camundongos , Animais , AMP Cíclico/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Recidiva Local de Neoplasia/genética , GMP Cíclico/metabolismo , Nucleotídeos Cíclicos , Aspirina , Hidrogéis , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genéticaRESUMO
MIWI, a murine member of PIWI proteins mostly expressed during male meiosis, is crucial for piRNA biogenesis, post-transcriptional regulation, and spermiogenesis. However, its meiotic function remains unknown. Here, we report that MIWI deficiency alters meiotic kinetochore assembly, significantly increases chromosome misalignment at the meiosis metaphase I plate, and causes chromosome mis-segregation. Consequently, Miwi-deficient mice show elevated aneuploidy in metaphase II and spermatid death. Furthermore, in Miwi-null and Miwi slicer-deficient mutants, major and minor satellite RNAs from centromeric and pericentromeric satellite repeats accumulate in excess. Over-expression of satellite repeats in wild-type spermatocytes also causes elevated chromosome misalignment, whereas reduction of both strands of major or minor satellite RNAs results in lower frequencies of chromosome misalignment. We show that MIWI, guided by piRNA, cleaves major satellite RNAs, generating RNA fragments that may form substrates for subsequent Dicer cleavage. Furthermore, Dicer cleaves all satellite RNAs in conjunction with MIWI. These findings reveal a novel mechanism in which MIWI- and Dicer-mediated cleavage of the satellite RNAs prevents the over-expression of satellite RNAs, thus ensuring proper kinetochore assembly and faithful chromosome segregation during meiosis.
Assuntos
Aneuploidia , Proteínas Argonautas/metabolismo , Segregação de Cromossomos , Cromossomos de Mamíferos/metabolismo , Meiose , Estabilidade de RNA , RNA Satélite/metabolismo , Animais , Proteínas Argonautas/genética , Cromossomos de Mamíferos/genética , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Cinetocoros/metabolismo , Camundongos , Camundongos Transgênicos , RNA Satélite/genética , Ribonuclease III/genética , Ribonuclease III/metabolismoRESUMO
BACKGROUND: Atezolizumab plus bevacizumab (atezo-bev) has been recommended for advanced hepatocellular carcinoma (HCC). High-dose external beam radiotherapy (RT) is recognized for its excellent local tumor control. The efficacy and safety of concurrent atezo-bev with RT for highly advanced HCC has been minimally explored. METHODS: In this preliminary retrospective study, we assessed patients with highly advanced HCC, characterized by Vp4 portal vein thrombosis or tumors exceeding 50% of liver volume, who received concurrent atezo-bev and RT (group A). Group A included 13 patients who received proton radiation at a dose of 72.6 GyE in 22 fractions, and one patient who received photon radiation at a dose of 54 Gy in 18 fractions. This group was compared with 34 similar patients treated atezo-bev alone as a control (group B). The primary objectives were to evaluate the objective response rate (ORR), overall survival (OS), and safety. RESULTS: Baseline characteristics were similar between groups, except for a higher incidence of Vp4 portal vein thrombosis in group A (78.6% vs. 21.4%, Pâ =â .05). Group A achieved a higher ORR (50.0% vs. 11.8%, Pâ <â .01) and a longer OS (not reached vs. 5.5 months, Pâ =â .01) after a median follow-up of 5.2 months. Multivariate analysis indicated that concurrent RT independently favored longer OS (hazard ratio: 0.18; 95% CI, 0.05-0.63, Pâ <â .01). Group A did not increase any grade adverse events (78.6% vs. 58.8%, Pâ =â .19) or severe adverse events of gradeâ ≥â 3 (14.3% vs. 14.7%, Pâ =â .97) compared to group B. CONCLUSIONS: The concurrent high-dose external beam radiotherapy appears to safely enhance the effectiveness of atezolizumab plus bevacizumab for highly advanced patients with HCC. Further studies are warranted to confirm these findings.
Assuntos
Anticorpos Monoclonais Humanizados , Bevacizumab , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Bevacizumab/uso terapêutico , Bevacizumab/administração & dosagem , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Masculino , Feminino , Anticorpos Monoclonais Humanizados/uso terapêutico , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/métodos , AdultoRESUMO
Stimuli-responsive ion nanochannels have attracted considerable attention in various fields because of their remote controllability of ionic transportation. For photoresponsive ion nanochannels, however, achieving precise regulation of ion conductivity is still challenging, primarily due to the difficulty of programmable structural changes in confined environments. Moreover, the relationship between noncontact photo-stimulation in nanoscale and light-induced ion conductivity has not been well understood. In this work, a versatile design for fabricating guard cell-inspired photoswitchable ion channels is presented by infiltrating azobenzene-cross-linked polymer (AAZO-PDAC) into nanoporous anodic aluminum oxide (AAO) membranes. The azobenzene-cross-linked polymer is formed by azobenzene chromophore (AAZO)-cross-linked poly(diallyldimethylammonium chloride) (PDAC) with electrostatic interactions. Under UV irradiation, the trans-AAZO isomerizes to the cis-AAZO, causing the volume compression of the polymer network, whereas, in darkness, the cis-AAZO reverts to the trans-AAZO, leading to the recovery of the structure. Consequently, the resultant nanopore sizes can be manipulated by the photomechanical effect of the AAZO-PDAC polymers. By adding ionic liquids, the ion conductivity of the light-driven ion nanochannels can be controlled with good repeatability and fast responses (within seconds) in multiple cycles. The ion channels have promising potential in the applications of biomimetic materials, sensors, and biomedical sciences.
RESUMO
IMPORTANCE: Vaccinia virus infection requires virus-cell membrane fusion to complete entry during endocytosis; however, it contains a large viral fusion protein complex of 11 viral proteins that share no structure or sequence homology to all the known viral fusion proteins, including type I, II, and III fusion proteins. It is thus very challenging to investigate how the vaccinia fusion complex works to trigger membrane fusion with host cells. In this study, we crystallized the ectodomain of vaccinia H2 protein, one component of the viral fusion complex. Furthermore, we performed a series of mutational, biochemical, and molecular analyses and identified two surface loops containing 170LGYSG174 and 125RRGTGDAW132 as the A28-binding region. We also showed that residues in the N-terminal helical region (amino acids 51-90) are also important for H2 function.
Assuntos
Fusão de Membrana , Vaccinia virus , Proteínas Virais de Fusão , Internalização do Vírus , Vaccinia virus/química , Vaccinia virus/genética , Vaccinia virus/metabolismo , Proteínas Virais de Fusão/química , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/metabolismoRESUMO
BACKGROUND: Spontaneous intracerebral hemorrhage (ICH) is a condition associated with high mortality and morbidity. Survivors may require prolonged intubation with mechanical ventilation (MV). The aim of this study was to analyze the predictors of extubation failure and prolonged MV in patients who undergo surgical evacuation. METHODS: This retrospective study was conducted on adult patients with ICH who underwent MV for at least 48 h and survived > 14 days after surgery. The demographics, clinical characteristics, laboratory tests, and Glasgow Coma Scale score were analyzed. RESULTS: A total of 134 patients with ICH were included in the study. The average age of the patients was 60.34 ± 15.59 years, and 79.9% (n = 107) were extubated after satisfying the weaning parameters. Extubation failure occurred in 11.2% (n = 12) and prolonged MV in 48.5% (n = 65) patients. Multivariable regression analysis revealed that a white blood cell count > 10,000/mm3 at the time of extubation was an independent predictor of reintubation. Meanwhile, age and initial Glasgow Coma Scale scores were predictors of prolonged MV. CONCLUSIONS: This study provided the first comprehensive characterization and analysis of the predictors of extubation failure and prolonged MV in patients with ICH after surgery. Knowledge of potential predictors is essential to improve the strategies for early initiation of adequate treatment and prognosis assessment in the early stages of the disease.
Assuntos
Extubação , Respiração Artificial , Adulto , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Extubação/efeitos adversos , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/cirurgia , PrognósticoRESUMO
PURPOSE: Mu-opioid receptors (MORs) are widely expressed in the central nervous system (CNS), peripheral organs, and immune system. This study measured the whole body distribution of MORs in rhesus macaques using the MOR selective radioligand [11C]carfentanil ([11C]CFN) on the PennPET Explorer. Both baseline and blocking studies were conducted using either naloxone or GSK1521498 to measure the effect of the antagonists on MOR binding in both CNS and peripheral organs. METHODS: The PennPET Explorer was used for MOR total-body PET imaging in four rhesus macaques using [11C]CFN under baseline, naloxone pretreatment, and naloxone or GSK1521498 displacement conditions. Logan distribution volume ratio (DVR) was calculated by using a reference model to quantitate brain regions, and the standard uptake value ratios (SUVRs) were calculated for peripheral organs. The percent receptor occupancy (%RO) was calculated to establish the blocking effect of 0.14 mg/kg naloxone or GSK1521498. RESULTS: The %RO in MOR-abundant brain regions was 75-90% for naloxone and 72-84% for GSK1521498 in blocking studies. A higher than 90% of %RO were observed in cervical spinal cord for both naloxone and GSK1521498. It took approximately 4-6 min for naloxone or GSK1521498 to distribute to CNS and displace [11C]CFN from the MOR. A smaller effect was observed in heart wall in the naloxone and GSK1521498 blocking studies. CONCLUSION: [11C]CFN total-body PET scans could be a useful approach for studying mechanism of action of MOR drugs used in the treatment of acute and chronic opioid use disorder and their effect on the biodistribution of synthetic opioids such as CFN. GSK1521498 could be a potential naloxone alternative to reverse opioid overdose.
RESUMO
Traditional screen printing is an easy approach commonly used for conductive pattern fabrication of electronics but lacks high resolution. Photolithography offers better resolution but is complex. Photosensitive silver pastes (PSP) combine the benefits of both but suffer from undercut issues, causing uneven etching, decreased interfacial adhesion, and thus poor resolutions. In this study, we explore the use of molecular precursors (i.e., silver oxalate) to replace metallic silver particles and enhance the depth of light penetration. Our findings demonstrate a successful solution to the undercut issue, achieving an undercut index of 1.0, indicating an undercut-free scenario and enabling higher resolutions in line and pattern formation. Additionally, our research confirms the feasibility of multilayer stacking of photosensitive pastes, achieving unprecedented aspect ratios in line patterns. By replacing 25% of micrometer silver powder with silver oxalate (PSP-25), we achieved optimal line widths as fine as 10 µm. The three-layer stack of PSP-25 reached a substantial aspect ratio with a height of 29.4 µm and an optimal fringe pattern resolution of 10 µm line width with a 15 µm aisle width. Utilization of silver oxalate was observed to slightly expand the line width, likely due to light scattering by the fine silver nanoparticles (â¼40 nm) formed during the photodecomposition of silver oxalate.
RESUMO
This study compared the effects of megestrol acetate (MA) prophylactic (p-MA) versus reactive (r-MA) use for critical body-weight loss (>5% from baseline) during concurrent chemoradiotherapy (CCRT) in patients with advanced pharyngolaryngeal squamous cell carcinoma (PLSCC).Patients receiving CCRT alone in two phase-II trials were included for analyses. Both the p-MA and r-MA cohorts received the same treatment protocol at the same institution, and the critical body-weight loss, survival, and adverse event profiles were compared.The mean (SD) weight loss was 5.1% (4.7%) in the p-MA cohort (n = 54) vs. 8.1% (4.6%) in the r-MA cohort (n = 50) (p = .001). The percentage of subjects with body-weight loss >5% was 42.6% in the p-MA cohort vs. 68.0% in the r-MA cohort (p = .011). Tube feeding was needed in 22.2% of p-MA vs. 62.0% of r-MA patients (p < .001). Less neutropenia (26.0% vs. 70.0% [p < .001]) and a shorter duration of grade 3-4 mucositis (2.4 ± 1.4 vs. 3.6 ± 2.0 wk [p = .009]) were observed with p-MA treatment. Disease-specific survival, locoregional control, or distant metastasis-free survival did not differ. Less competing mortality from secondary primary cancer resulted in a better overall survival trend in the p-MA cohort.p-MA may reduce body-weight loss and improve adverse event profiles during CCRT for patients with PLSCC.
Assuntos
Carcinoma de Células Escamosas , Quimiorradioterapia , Neoplasias Laríngeas , Acetato de Megestrol , Neoplasias Faríngeas , Redução de Peso , Humanos , Quimiorradioterapia/métodos , Quimiorradioterapia/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Laríngeas/terapia , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/patologia , Idoso , Acetato de Megestrol/uso terapêutico , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Neoplasias Faríngeas/terapia , Neoplasias Faríngeas/mortalidade , Adulto , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapiaRESUMO
This study determined the phase and crystallization behaviors of blends composed of asymmetric polystyrene-block-poly(ethylene oxide) (PS-PEO) and symmetric polystyrene-block-poly(methyl methacrylate) (PS-PMMA). The PS blocks in the various binary block copolymers exhibited nearly identical molecular weights, whereas the molecular weight ratios of PEO and PMMA varied. The compatibility of the PEO and PMMA chains aided the binary block copolymers in co-ordering in a lamellar microdomain morphology, with the PEO and PMMA blocks sharing a common microdomain. Adding short tethered PMMA chains to long tethered PEO chains led to a decrease in the common microdomain spacing and an increase in the grafting density. These behaviors increased PEO chain stretching, causing macrophase separation. The mismatch in PEO and PMMA block lengths divided the common PEO/PMMA microdomain into two sections: the coexisting PEO/PMMA section close to the microdomain interface and the neat PEO section far away from it. The high-glass-transition-temperature PMMA reduced PEO chain mobility, inhibiting PEO crystallization in the coexisting PEO/PMMA section but not in the neat PEO section. When the block length ratio of PEO to PMMA decreased, the neat PEO section narrowed. The increase in the extent of PEO confinement led to a reduction in PEO crystallizability.
RESUMO
The synucleinopathies are a diverse group of neurodegenerative disorders characterized by the accumulation of aggregated alpha-synuclein (aSyn) in vulnerable populations of brain cells. Oxidative stress is both a cause and a consequence of aSyn aggregation in the synucleinopathies; however, noninvasive methods for detecting oxidative stress in living animals have proven elusive. In this study, we used the reactive oxygen species (ROS)-sensitive positron emission tomography (PET) radiotracer [18F]ROStrace to detect increases in oxidative stress in the widely-used A53T mouse model of synucleinopathy. A53T-specific elevations in [18F]ROStrace signal emerged at a relatively early age (6-8 months) and became more widespread within the brain over time, a pattern which paralleled the progressive development of aSyn pathology and oxidative damage in A53T brain tissue. Systemic administration of lipopolysaccharide (LPS) also caused rapid and long-lasting elevations in [18F]ROStrace signal in A53T mice, suggesting that chronic, aSyn-associated oxidative stress may render these animals more vulnerable to further inflammatory insult. Collectively, these results provide novel evidence that oxidative stress is an early and chronic process during the development of synucleinopathy and suggest that PET imaging with [18F]ROStrace holds promise as a means of detecting aSyn-associated oxidative stress noninvasively.
Assuntos
Encéfalo , Modelos Animais de Doenças , Estresse Oxidativo , Tomografia por Emissão de Pósitrons , Sinucleinopatias , alfa-Sinucleína , Animais , Sinucleinopatias/diagnóstico por imagem , Sinucleinopatias/metabolismo , Sinucleinopatias/patologia , Tomografia por Emissão de Pósitrons/métodos , Camundongos , alfa-Sinucleína/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Radioisótopos de Flúor , Masculino , Camundongos Transgênicos , Compostos Radiofarmacêuticos , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Oxaliplatin is commonly used to treat gastrointestinal malignancies. However, its applications are limited due to potential adverse drug reactions (ADRs), particularly severe anaphylactic shock. There is no method to predict or prevent ADRs caused by oxaliplatin. Therefore, we aimed to investigate the genetic HLA predisposition and immune mechanism of oxaliplatin-induced ADRs. METHODS: A retrospective review was performed for 154 patients with ADRs induced by oxaliplatin during 2016-2021 recorded in our ADR notification system. HLA genotyping was conducted for 47 patients with oxaliplatin-induced ADRs, 1100 general population controls, and 34 oxaliplatin-tolerant controls in 2019-2023. The in vitro basophil activation test (BAT) was performed and oxaliplatin-specific IgE levels were determined. RESULTS: The incidence of oxaliplatin-induced ADRs and anaphylactic shock in our cohort was 7.1% and 0.15%, respectively. Of the 154 patients, 67.5% suffered rash/eruption; 26.0% of the patients who could not undergo oxaliplatin rechallenge were considered to show oxaliplatin-induced immune-mediated hypersensitivity reactions (HRs). The genetic study found that the HLA-DRB∗12:01 allele was associated with oxaliplatin-induced HRs compared to the general population controls (sensitivity = 42.9%; odds ratio [OR] = 3.4; 95% CI = 1.4-8.2; P = 0.008) and tolerant controls (OR = 12; 95% CI = 2.3-63.7; P = 0.001). The in vitro BAT showed higher activation of CD63+ basophils in patients with oxaliplatin-induced HRs compared to the tolerant controls (P < 0.05). Only four patients (8.5%) with oxaliplatin-induced ADRs were positive for oxaliplatin-specific IgE. CONCLUSIONS: This study found that 26.0% of patients with oxaliplatin-induced ADRs could not undergo oxaliplatin rechallenge. HLA-DRB∗12:01 is regarded as a genetic marker for oxaliplatin-induced hypersensitivity.
RESUMO
Deactivation of G-protein-coupled receptors (GPCRs) involves multiple phosphorylations followed by arrestin binding, which uncouples the GPCR from G-protein activation. Some GPCRs, such as rhodopsin, are reused many times. Arrestin dissociation and GPCR dephosphorylation are key steps in the recycling process. In vitro evidence suggests that visual arrestin (ARR1) binding to light-activated, phosphorylated rhodopsin hinders dephosphorylation. Whether ARR1 binding also affects rhodopsin dephosphorylation in vivo is not known. We investigated this using both male and female mice lacking ARR1. Mice were exposed to bright light and placed in darkness for different periods of time, and differently phosphorylated species of rhodopsin were assayed by isoelectric focusing. For WT mice, rhodopsin dephosphorylation was nearly complete by 1 h in darkness. Surprisingly, we observed that, in the Arr1 KO rods, rhodopsin remained phosphorylated even after 3 h. Delayed dephosphorylation in Arr1 KO rods cannot be explained by cell stress induced by persistent signaling, since it is not prevented by the removal of transducin, the visual G-protein, nor can it be explained by downregulation of protein phosphatase 2A, the putative rhodopsin phosphatase. We further show that cone arrestin (ARR4), which binds light-activated, phosphorylated rhodopsin poorly, had little effect in enhancing rhodopsin dephosphorylation, whereas mice expressing binding-competent mutant ARR1-3A showed a similar time course of rhodopsin dephosphorylation as WT. Together, these results reveal a novel role of ARR1 in facilitating rhodopsin dephosphorylation in vivoSIGNIFICANCE STATEMENT G-protein-coupled receptors (GPCRs) are transmembrane proteins used by cells to receive and respond to a broad range of extracellular signals that include neurotransmitters, hormones, odorants, and light (photons). GPCR signaling is terminated by two sequential steps: phosphorylation and arrestin binding. Both steps must be reversed when GPCRs are recycled and reused. Dephosphorylation, which is required for recycling, is an understudied process. Using rhodopsin as a prototypical GPCR, we discovered that arrestin facilitated rhodopsin dephosphorylation in living mice.
Assuntos
Arrestina , Rodopsina , Animais , Arrestina/metabolismo , Feminino , Proteínas de Ligação ao GTP , Masculino , Camundongos , Fosforilação , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Rodopsina/genética , Rodopsina/metabolismoRESUMO
This is a retrospective cohort study by analyzing a multi-institutional electronic medical records database in Taiwan to compare long-term effectiveness and risk of major adverse cardiac events (MACE) in chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC) patients treated with enzalutamide (ENZ) or abiraterone (AA). Patients aged 20 years and older and newly receiving androgen receptor targeted therapies ENZ or AA from September 2016 to December 2019 were included. We followed patients from initiation of therapies to the occurrence of outcomes (prostate-specific antigen (PSA) response rate, PSA progression free survival (PFS), overall survival (OS), and MACE), death, the last clinical visit, or December 31, 2020. We performed multivariable Cox proportional hazard models to compare ENZ and AA groups for the measured outcomes. A total of 363 patients treated with either ENZ (n = 157) or AA (n = 206) were identified. The analysis found a significantly higher proportion of patients with a PSA response rate higher than 50% among those receiving ENZ than among those receiving AA (ENZ vs AA: 75.80% vs 63.59%, P = .01). However, there was no significant difference in PSA PFS (adjusted hazard ratio: 0.86; 95% CI 0.63-1.17) and OS (0.68: 0.41-1.14) between the use of ENZ and AA in chemotherapy-naïve mCRPC patients. Regarding the cardiovascular (CV) safety outcome, there was a significantly lower risk of MACE in patients receiving ENZ, compared to patients receiving AA (0.20: 0.07-0.55). The findings suggest that enzalutamide may be more efficacious for PSA response and suitable for chemotherapy-naïve mCRPC patients with high CV risk profile.
Assuntos
Doenças Cardiovasculares , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Nitrilas/uso terapêutico , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Hypoxic tumor microenvironment (HTM) promotes a more aggressive and malignant state in glioblastoma. However, little is known about the role and mechanism of CXC chemokine ligand 14 (CXCL14) in HTM-mediated glioblastoma progression. In this study, we report that CXCL14 expression correlated with poor outcomes, tumor grade, and hypoxia-inducible factor (HIF) expression in patients with glioblastoma. CXCL14 was upregulated in tumor cells within the hypoxic areas of glioblastoma. Hypoxia induced HIF-dependent expression of CXCL14, which promoted glioblastoma tumorigenicity and invasiveness in vitro and in vivo. Moreover, CXCL14 gain-of-function in glioblastoma cells activated insulin-like growth factor-1 receptor (IGF-1R) signal transduction to regulate the growth, invasiveness, and neurosphere formation of glioblastoma. Finally, systemic delivery of CXCL14 siRNA nanoparticles (NPs) with polysorbate 80 coating significantly suppressed tumor growth in vivo and extended the survival time in patient-derived glioblastoma xenografts. Together, these findings suggest that HIF-dependent CXCL14 expression contributes to HTM-promoted glioblastoma tumorigenicity and invasiveness through activation of the IGF-1R signaling pathway. CXCL14 siRNA NPs as an oligonucleotide drug can inhibit glioblastoma progression and constitute a translational path for the clinical treatment of glioblastoma patients.
Assuntos
Glioblastoma , Humanos , Glioblastoma/metabolismo , Quimiocinas CXC/genética , Fator de Crescimento Insulin-Like I , Ligantes , Hipóxia , Transdução de Sinais , RNA Interferente Pequeno , Linhagem Celular Tumoral , Microambiente TumoralRESUMO
BACKGROUND: The prognostic significance of the relapse interval in patients with resected oral cavity squamous cell carcinoma (OCSCC) is a matter of ongoing debate. In this large-scale, registry-based, nationwide study, we examined whether the time interval between surgery and the first disease relapse may affect survival outcomes in Taiwanese patients with OCSCC. METHODS: Data made available by the Taiwan Health Promotion Administration as of 2004 were obtained. The study cohort consisted of patients who were included in the registry between 2011 and 2017. Disease staging was performed according to the American Joint Committee on Cancer (AJCC) Staging Manual, Eight Edition. We retrospectively reviewed the clinical records of 13,789 patients with OCSCC who received surgical treatment. A total of 2327 (16.9%) patients experienced a first disease relapse. The optimal cutoff value for the relapse interval was 330 days when both 5-year disease-specific survival (DSS) and overall survival (OS) (≤ 330/>330 days, n = 1630/697) were taken into account. In addition, we undertook a propensity score (PS)-matched analysis of patients (n = 654 each) with early (≤ 330 days) versus late (> 330 days) relapse. RESULTS: The median follow-up time in the entire study cohort was 702 days (433 and 2001 days in the early and late relapse groups, respectively). Compared with patients who experienced late relapse, those with early relapse showed a higher prevalence of the following adverse prognostic factors: pT4, pN3, pStage IV, poor differentiation, depth of invasion ≥ 10 mm, and extra-nodal extension. Multivariable analysis revealed that early relapse was an independent adverse prognostic factor for both 5-year DSS and OS (average hazard ratios [AHRs]: 3.24 and 3.91, respectively). In the PS-matched cohort, patients who experienced early relapse showed less favorable 5-year DSS: 58% versus 30%, p < 0.0001 (AHR: 3.10 [2.69 - 3.57]) and OS: 49% versus 22%, p < 0.0001 (AHR: 3.32 [2.89 - 3.81]). CONCLUSION: After adjustment for potential confounders and PS matching, early relapse was an adverse prognostic factor for survival outcomes in patients with OCSCC. Our findings may have significant implications for risk stratification.