RESUMO
The development of functional neurons is a complex orchestration of multiple signaling pathways controlling cell proliferation and differentiation. Because the balance of antioxidants is important for neuronal survival and development, we hypothesized that ferroptosis must be suppressed to gain neurons. We find that removal of antioxidants diminishes neuronal development and laminar organization of cortical organoids, which is fully restored when ferroptosis is inhibited by ferrostatin-1 or when neuronal differentiation occurs in the presence of vitamin A. Furthermore, iron-overload-induced developmental growth defects in C. elegans are ameliorated by vitamin E and A. We determine that all-trans retinoic acid activates the Retinoic Acid Receptor, which orchestrates the expression of anti-ferroptotic genes. In contrast, retinal and retinol show radical-trapping antioxidant activity. Together, our study reveals an unexpected function of vitamin A in coordinating the expression of essential cellular gatekeepers of ferroptosis, and demonstrates that suppression of ferroptosis by radical-trapping antioxidants or by vitamin A is required to obtain mature neurons and proper laminar organization in cortical organoids.
Assuntos
Antioxidantes , Caenorhabditis elegans , Ferroptose , Neurônios , Vitamina A , Animais , Ferroptose/efeitos dos fármacos , Vitamina A/farmacologia , Vitamina A/metabolismo , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efeitos dos fármacos , Antioxidantes/farmacologia , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/citologia , Cicloexilaminas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Vitamina E/farmacologia , Receptores do Ácido Retinoico/metabolismo , Receptores do Ácido Retinoico/genética , Tretinoína/farmacologia , Organoides/efeitos dos fármacos , Organoides/metabolismo , Neurogênese/efeitos dos fármacos , Camundongos , Humanos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Transdução de Sinais/efeitos dos fármacos , FenilenodiaminasRESUMO
Precision medicine has revolutionised cancer treatments; however, actionable biomarkers remain scarce. To address this, we develop the Oncology Biomarker Discovery (OncoBird) framework for analysing the molecular and biomarker landscape of randomised controlled clinical trials. OncoBird identifies biomarkers based on single genes or mutually exclusive genetic alterations in isolation or in the context of tumour subtypes, and finally, assesses predictive components by their treatment interactions. Here, we utilise the open-label, randomised phase III trial (FIRE-3, AIO KRK-0306) in metastatic colorectal carcinoma patients, who received either cetuximab or bevacizumab in combination with 5-fluorouracil, folinic acid and irinotecan (FOLFIRI). We systematically identify five biomarkers with predictive components, e.g., patients with tumours that carry chr20q amplifications or lack mutually exclusive ERK signalling mutations benefited from cetuximab compared to bevacizumab. In summary, OncoBird characterises the molecular landscape and outlines actionable biomarkers, which generalises to any molecularly characterised randomised controlled trial.
Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Bevacizumab/uso terapêutico , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase III como AssuntoRESUMO
Hospital staff are at high risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during the coronavirus disease (COVID-19) pandemic. This cross-sectional study aimed to determine the prevalence of SARS-CoV-2 infection in hospital staff at the University Hospital rechts der Isar in Munich, Germany, and identify modulating factors. Overall seroprevalence of SARS-CoV-2-IgG in 4,554 participants was 2.4%. Staff engaged in direct patient care, including those working in COVID-19 units, had a similar probability of being seropositive as non-patient-facing staff. Increased probability of infection was observed in staff reporting interactions with SARS-CoV-2âinfected coworkers or private contacts or exposure to COVID-19 patients without appropriate personal protective equipment. Analysis of spatiotemporal trajectories identified that distinct hotspots for SARS-CoV-2âpositive staff and patients only partially overlap. Patient-facing work in a healthcare facility during the SARS-CoV-2 pandemic might be safe as long as adequate personal protective equipment is used and infection prevention practices are followed inside and outside the hospital.
Assuntos
COVID-19 , SARS-CoV-2 , Estudos Transversais , Alemanha/epidemiologia , Pessoal de Saúde , Hospitais Universitários , Humanos , Imunoglobulina G , Controle de Infecções , Recursos Humanos em Hospital , Prevalência , Estudos SoroepidemiológicosRESUMO
BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disorder whose prevalence is rapidly increasing worldwide. The molecular mechanisms underpinning the pathophysiology of sporadic PD remain incompletely understood. Therefore, causative therapies are still elusive. To obtain a more integrative view of disease-mediated alterations, we investigated the molecular landscape of PD in human post-mortem midbrains, a region that is highly affected during the disease process. METHODS: Tissue from 19 PD patients and 12 controls were obtained from the Parkinson's UK Brain Bank and subjected to multi-omic analyses: small and total RNA sequencing was performed on an Illumina's HiSeq4000, while proteomics experiments were performed in a hybrid triple quadrupole-time of flight mass spectrometer (TripleTOF5600+) following quantitative sequential window acquisition of all theoretical mass spectra. Differential expression analyses were performed with customized frameworks based on DESeq2 (for RNA sequencing) and with Perseus v.1.5.6.0 (for proteomics). Custom pipelines in R were used for integrative studies. RESULTS: Our analyses revealed multiple deregulated molecular targets linked to known disease mechanisms in PD as well as to novel processes. We have identified and experimentally validated (quantitative real-time polymerase chain reaction/western blotting) several PD-deregulated molecular candidates, including miR-539-3p, miR-376a-5p, miR-218-5p and miR-369-3p, the valid miRNA-mRNA interacting pairs miR-218-5p/RAB6C and miR-369-3p/GTF2H3, as well as multiple proteins, such as CHI3L1, HSPA1B, FNIP2 and TH. Vertical integration of multi-omic analyses allowed validating disease-mediated alterations across different molecular layers. Next to the identification of individual molecular targets in all explored omics layers, functional annotation of differentially expressed molecules showed an enrichment of pathways related to neuroinflammation, mitochondrial dysfunction and defects in synaptic function. CONCLUSIONS: This comprehensive assessment of PD-affected and control human midbrains revealed multiple molecular targets and networks that are relevant to the disease mechanism of advanced PD. The integrative analyses of multiple omics layers underscore the importance of neuroinflammation, immune response activation, mitochondrial and synaptic dysfunction as putative therapeutic targets for advanced PD.
Assuntos
Mesencéfalo/patologia , Terapia de Alvo Molecular/métodos , Doença de Parkinson/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Mesencéfalo/anatomia & histologia , Mesencéfalo/efeitos dos fármacos , Pessoa de Meia-Idade , Terapia de Alvo Molecular/estatística & dados numéricos , Doença de Parkinson/genética , Doença de Parkinson/mortalidade , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/estatística & dados numéricos , Reino UnidoRESUMO
High-throughput testing of drugs across molecular-characterised cell lines can identify candidate treatments and discover biomarkers. However, the cells' response to a drug is typically quantified by a summary statistic from a best-fit dose-response curve, whilst neglecting the uncertainty of the curve fit and the potential variability in the raw readouts. Here, we model the experimental variance using Gaussian Processes, and subsequently, leverage uncertainty estimates to identify associated biomarkers with a new Bayesian framework. Applied to in vitro screening data on 265 compounds across 1074 cancer cell lines, our models identified 24 clinically established drug-response biomarkers, and provided evidence for six novel biomarkers by accounting for association with low uncertainty. We validated our uncertainty estimates with an additional drug screen of 26 drugs, 10 cell lines with 8 to 9 replicates. Our method is applicable to any dose-response data without replicates, and improves biomarker discovery for precision medicine.
Assuntos
Antineoplásicos , Biomarcadores Tumorais/análise , Descoberta de Drogas/métodos , Descoberta de Drogas/normas , Estatística como Assunto/métodos , Linhagem Celular Tumoral , Ensaios de Triagem em Larga Escala/métodos , Ensaios de Triagem em Larga Escala/normas , HumanosRESUMO
High-throughput drug screens in cancer cell lines test compounds at low concentrations, thereby enabling the identification of drug-sensitivity biomarkers, while resistance biomarkers remain underexplored. Dissecting meaningful drug responses at high concentrations is challenging due to cytotoxicity, i.e., off-target effects, thus limiting resistance biomarker discovery to frequently mutated cancer genes. To address this, we interrogate subpopulations carrying sensitivity biomarkers and consecutively investigate unexpectedly resistant (UNRES) cell lines for unique genetic alterations that may drive resistance. By analyzing the GDSC and CTRP datasets, we find 53 and 35 UNRES cases, respectively. For 24 and 28 of them, we highlight putative resistance biomarkers. We find clinically relevant cases such as EGFRT790M mutation in NCI-H1975 or PTEN loss in NCI-H1650 cells, in lung adenocarcinoma treated with EGFR inhibitors. Interrogating the underpinnings of drug resistance with publicly available CRISPR phenotypic assays assists in prioritizing resistance drivers, offering hypotheses for drug combinations.