RESUMEN
Bacteria encode reverse transcriptases (RTs) of unknown function that are closely related to group II intron-encoded RTs. We found that a Pseudomonas aeruginosa group II intron-like RT (G2L4 RT) with YIDD instead of YADD at its active site functions in DNA repair in its native host and when expressed in Escherichia coli. G2L4 RT has biochemical activities strikingly similar to those of human DNA repair polymerase θ and uses them for translesion DNA synthesis and double-strand break repair (DSBR) via microhomology-mediated end-joining (MMEJ). We also found that a group II intron RT can function similarly in DNA repair, with reciprocal active-site substitutions showing isoleucine favors MMEJ and alanine favors primer extension in both enzymes. These DNA repair functions utilize conserved structural features of non-LTR-retroelement RTs, including human LINE-1 and other eukaryotic non-LTR-retrotransposon RTs, suggesting such enzymes may have inherent ability to function in DSBR in a wide range of organisms.
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ADN Polimerasa Dirigida por ARN , Retroelementos , Alanina/genética , Reparación del ADN por Unión de Extremidades , Reparación del ADN , ARN Polimerasas Dirigidas por ADN/genética , Humanos , Intrones , Isoleucina/genética , ADN Polimerasa Dirigida por ARN/químicaRESUMEN
How tumor cells genetically lose antigenicity and evade immune checkpoints remains largely elusive. We report that tissue-specific expression of the human long noncoding RNA LINK-A in mouse mammary glands initiates metastatic mammary gland tumors, which phenotypically resemble human triple-negative breast cancer (TNBC). LINK-A expression facilitated crosstalk between phosphatidylinositol-(3,4,5)-trisphosphate and inhibitory G-protein-coupled receptor (GPCR) pathways, attenuating protein kinase A-mediated phosphorylation of the E3 ubiquitin ligase TRIM71. Consequently, LINK-A expression enhanced K48-polyubiquitination-mediated degradation of the antigen peptide-loading complex (PLC) and intrinsic tumor suppressors Rb and p53. Treatment with LINK-A locked nucleic acids or GPCR antagonists stabilized the PLC components, Rb and p53, and sensitized mammary gland tumors to immune checkpoint blockers. Patients with programmed ccll death protein-1(PD-1) blockade-resistant TNBC exhibited elevated LINK-A levels and downregulated PLC components. Hence we demonstrate lncRNA-dependent downregulation of antigenicity and intrinsic tumor suppression, which provides the basis for developing combinational immunotherapy treatment regimens and early TNBC prevention.
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Presentación de Antígeno/inmunología , Regulación Neoplásica de la Expresión Génica , Neoplasias/genética , Neoplasias/inmunología , Oncogenes , ARN Largo no Codificante/genética , Escape del Tumor/genética , Escape del Tumor/inmunología , Adenoma/genética , Adenoma/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Ratones , Neoplasias/metabolismo , Neoplasias/patología , Fosforilación , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitinación , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Impaired DNA crosslink repair leads to Fanconi anemia (FA), characterized by a unique manifestation of bone marrow failure and pancytopenia among diseases caused by DNA damage response defects. As a germline disorder, why the hematopoietic hierarchy is specifically affected is not fully understood. We find that reprogramming transcription during hematopoietic differentiation results in an overload of genotoxic stress, which causes aborted differentiation and depletion of FA mutant progenitor cells. DNA damage onset most likely arises from formaldehyde, an obligate by-product of oxidative protein demethylation during transcription regulation. Our results demonstrate that rapid and extensive transcription reprogramming associated with hematopoietic differentiation poses a major threat to genome stability and cell viability in the absence of the FA pathway. The connection between differentiation and DNA damage accumulation reveals a novel mechanism of genome scarring and is critical to exploring therapies to counteract the aplastic anemia for the treatment of FA patients.
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Diferenciación Celular/efectos de los fármacos , Reprogramación Celular/genética , Anemia de Fanconi/genética , Formaldehído/toxicidad , Daño del ADN/efectos de los fármacos , Reparación del ADN/genética , Anemia de Fanconi/sangre , Anemia de Fanconi/patología , Formaldehído/metabolismo , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/genética , Inestabilidad Genómica/genética , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Células K562 , Transcripción GenéticaRESUMEN
The ZIKA virus (ZIKV) evades the host immune response by degrading STAT2 through its NS5 protein, thereby inhibiting type I interferon (IFN)-mediated antiviral immunity. However, the molecular mechanism underlying this process has remained elusive. In this study, we performed a genome-wide CRISPR/Cas9 screen, revealing that ZSWIM8 as the substrate receptor of Cullin3-RING E3 ligase is required for NS5-mediated STAT2 degradation. Genetic depletion of ZSWIM8 and CUL3 substantially impeded NS5-mediated STAT2 degradation. Biochemical analysis illuminated that NS5 enhances the interaction between STAT2 and the ZSWIM8-CUL3 E3 ligase complex, thereby facilitating STAT2 ubiquitination. Moreover, ZSWIM8 knockout endowed A549 and Huh7 cells with partial resistance to ZIKV infection and protected cells from the cytopathic effects induced by ZIKV, which was attributed to the restoration of STAT2 levels and the activation of IFN signaling. Subsequent studies in a physiologically relevant model, utilizing human neural progenitor cells, demonstrated that ZSWIM8 depletion reduced ZIKV infection, resulting from enhanced IFN signaling attributed to the sustained levels of STAT2. Our findings shed light on the role of ZIKV NS5, serving as the scaffold protein, reprograms the ZSWIM8-CUL3 E3 ligase complex to orchestrate STAT2 proteasome-dependent degradation, thereby facilitating evasion of IFN antiviral signaling. Our study provides unique insights into ZIKV-host interactions and holds promise for the development of antivirals and prophylactic vaccines.
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Proteínas Cullin , Interferón Tipo I , Proteolisis , Factor de Transcripción STAT2 , Transducción de Señal , Ubiquitina-Proteína Ligasas , Ubiquitinación , Proteínas no Estructurales Virales , Infección por el Virus Zika , Virus Zika , Humanos , Factor de Transcripción STAT2/metabolismo , Virus Zika/inmunología , Virus Zika/fisiología , Virus Zika/metabolismo , Proteínas no Estructurales Virales/metabolismo , Proteínas no Estructurales Virales/genética , Interferón Tipo I/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Infección por el Virus Zika/metabolismo , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/virología , Proteínas Cullin/metabolismo , Células A549 , Células HEK293 , Sistemas CRISPR-CasRESUMEN
Synaptic transmission involves a fast synchronous phase and a slower asynchronous phase of neurotransmitter release that are regulated by distinct Ca(2+) sensors. Though the Ca(2+) sensor for rapid exocytosis, synaptotagmin I, has been studied in depth, the sensor for asynchronous release remains unknown. In a screen for neuronal Ca(2+) sensors that respond to changes in [Ca(2+)] with markedly slower kinetics than synaptotagmin I, we observed that Doc2--another Ca(2+), SNARE, and lipid-binding protein--operates on timescales consistent with asynchronous release. Moreover, up- and downregulation of Doc2 expression levels in hippocampal neurons increased or decreased, respectively, the slow phase of synaptic transmission. Synchronous release, when triggered by single action potentials, was unaffected by manipulation of Doc2 but was enhanced during repetitive stimulation in Doc2 knockdown neurons, potentially due to greater vesicle availability. In summary, we propose that Doc2 is a Ca(2+) sensor that is kinetically tuned to regulate asynchronous neurotransmitter release.
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Proteínas de Unión al Calcio/metabolismo , Calcio/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Neurotransmisores/metabolismo , Transmisión Sináptica , Potenciales de Acción , Animales , Células Cultivadas , Técnicas de Silenciamiento del Gen , Hipocampo/citología , Hipocampo/metabolismo , Humanos , Metabolismo de los Lípidos , Ratones , Neuronas/metabolismo , Ratas , Proteínas SNARE/metabolismo , Vesículas Sinápticas/metabolismo , Sinaptotagmina I/genética , Sinaptotagmina I/metabolismoRESUMEN
Harvesting energy from the environment offers the promise of clean power for self-sustained systems1,2. Known technologies-such as solar cells, thermoelectric devices and mechanical generators-have specific environmental requirements that restrict where they can be deployed and limit their potential for continuous energy production3-5. The ubiquity of atmospheric moisture offers an alternative. However, existing moisture-based energy-harvesting technologies can produce only intermittent, brief (shorter than 50 seconds) bursts of power in the ambient environment, owing to the lack of a sustained conversion mechanism6-12. Here we show that thin-film devices made from nanometre-scale protein wires harvested from the microbe Geobacter sulfurreducens can generate continuous electric power in the ambient environment. The devices produce a sustained voltage of around 0.5 volts across a 7-micrometre-thick film, with a current density of around 17 microamperes per square centimetre. We find the driving force behind this energy generation to be a self-maintained moisture gradient that forms within the film when the film is exposed to the humidity that is naturally present in air. Connecting several devices linearly scales up the voltage and current to power electronics. Our results demonstrate the feasibility of a continuous energy-harvesting strategy that is less restricted by location or environmental conditions than other sustainable approaches.
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Prokaryotic CRISPR-Cas systems provide adaptive immunity by integrating portions of foreign nucleic acids (spacers) into genomic CRISPR arrays. Cas6 proteins then process CRISPR array transcripts into spacer-derived RNAs (CRISPR RNAs; crRNAs) that target Cas nucleases to matching invaders. We find that a Marinomonas mediterranea fusion protein combines three enzymatic domains (Cas6, reverse transcriptase [RT], and Cas1), which function in both crRNA biogenesis and spacer acquisition from RNA and DNA. We report a crystal structure of this divergent Cas6, identify amino acids required for Cas6 activity, show that the Cas6 domain is required for RT activity and RNA spacer acquisition, and demonstrate that CRISPR-repeat binding to Cas6 regulates RT activity. Co-evolution of putative interacting surfaces suggests a specific structural interaction between the Cas6 and RT domains, and phylogenetic analysis reveals repeated, stable association of free-standing Cas6s with CRISPR RTs in multiple microbial lineages, indicating that a functional interaction between these proteins preceded evolution of the fusion.
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Proteínas Asociadas a CRISPR/fisiología , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/fisiología , ADN Polimerasa Dirigida por ARN/fisiología , Secuencia de Bases/genética , Sistemas CRISPR-Cas/fisiología , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , ADN , Endonucleasas , Marinomonas/genética , Marinomonas/metabolismo , Filogenia , ARN/biosíntesis , Especificidad por SustratoRESUMEN
Single-cell RNA sequencing (scRNA-seq) has emerged as a powerful tool for uncovering cellular heterogeneity. However, the high costs associated with this technique have rendered it impractical for studying large patient cohorts. We introduce ENIGMA (Deconvolution based on Regularized Matrix Completion), a method that addresses this limitation through accurately deconvoluting bulk tissue RNA-seq data into a readout with cell-type resolution by leveraging information from scRNA-seq data. By employing a matrix completion strategy, ENIGMA minimizes the distance between the mixture transcriptome obtained with bulk sequencing and a weighted combination of cell-type-specific expression. This allows the quantification of cell-type proportions and reconstruction of cell-type-specific transcriptomes. To validate its performance, ENIGMA was tested on both simulated and real datasets, including disease-related tissues, demonstrating its ability in uncovering novel biological insights.
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Perfilación de la Expresión Génica , Transcriptoma , Humanos , Perfilación de la Expresión Génica/métodos , Programas Informáticos , RNA-Seq/métodos , Análisis de Secuencia de ARN/métodosRESUMEN
Pancreatic ductal adenocarcinoma (PDAC) remains recalcitrant to all forms of cancer treatment and carries a five-year survival rate of only 8%1. Inhibition of oncogenic KRAS (hereafter KRAS*), the earliest lesion in disease development that is present in more than 90% of PDACs, and its signalling surrogates has yielded encouraging preclinical results with experimental agents2-4. However, KRAS*-independent disease recurrence following genetic extinction of Kras* in mouse models anticipates the need for co-extinction strategies5,6. Multiple oncogenic processes are initiated at the cell surface, where KRAS* physically and functionally interacts to direct signalling that is essential for malignant transformation and tumour maintenance. Insights into the complexity of the functional cell-surface-protein repertoire (surfaceome) have been technologically limited until recently and-in the case of PDAC-the genetic control of the function and composition of the PDAC surfaceome in the context of KRAS* signalling remains largely unknown. Here we develop an unbiased, functional target-discovery platform to query KRAS*-dependent changes of the PDAC surfaceome, which reveals syndecan 1 (SDC1, also known as CD138) as a protein that is upregulated at the cell surface by KRAS*. Localization of SDC1 at the cell surface-where it regulates macropinocytosis, an essential metabolic pathway that fuels PDAC cell growth-is essential for disease maintenance and progression. Thus, our study forges a mechanistic link between KRAS* signalling and a targetable molecule driving nutrient salvage pathways in PDAC and validates oncogene-driven surfaceome annotation as a strategy to identify cancer-specific vulnerabilities.
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Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/patología , Pinocitosis , Sindecano-1/metabolismo , Factor 6 de Ribosilación del ADP , Factores de Ribosilacion-ADP/metabolismo , Animales , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Proliferación Celular , Progresión de la Enfermedad , Femenino , Factores de Intercambio de Guanina Nucleótido/metabolismo , Humanos , Masculino , Ratones , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Transducción de SeñalRESUMEN
Age-related cataract (ARC) is regarded as the principal cause of vision impairment among the aged. The regulatory role of long noncoding RNAs (LncRNAs) in ARC remains unclear. The lncRNA maternally expressed gene 3 (MEG3) has been reported to promote ARC progression, and the underlying mechanism was further investigated in this study. Lens epithelium samples were collected to verify the expression of MEG3. Lens epithelial cells (LECs) were treated with H2O2 to mimic microenvironment of ARC in vitro. Cell viability, reactive oxygen species, and ferroptosis were evaluated during the in viro experiments. In the present work, lncRNA MEG3 was highly expressed in ARC group, compared with normal group. MEG3 was induced, cell viability and glutathione peroxidase 4 (GPX4) level were inhibited, and ferroptosis was promoted in H2O2 treated LECs. LncRNA MEG3 silence reversed the effects of H2O2 on viability and ferroptosis in LECs. Thereafter, lncRNA MEG3 was found to bind to PTBP1 for GPX4 degradation. Silencing of GPX4 reversed the regulation of lncRNA MEG3 inhibition in H2O2-treated LECs. To sum up, lncRNA MEG3 exhibited high expression in ARC. In H2O2-induced LECs, inhibition of lncRNA MEG3 accelerated cell viability and repressed ferroptosis by interaction with PTBP1 for GPX4 messenger RNA decay. Targeting lncRNA MEG3 may be a novel treatment of ARC.
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Intronic polyadenylation (IpA) usually leads to changes in the coding region of an mRNA, and its implication in diseases has been recognized, although at its very beginning status. Conveniently and accurately identifying IpA is of great importance for further evaluating its biological significance. Here, we developed IPAFinder, a bioinformatic method for the de novo identification of intronic poly(A) sites and their dynamic changes from standard RNA-seq data. Applying IPAFinder to 256 pan-cancer tumor/normal pairs across six tumor types, we discovered 490 recurrent dynamically changed IpA events, some of which are novel and derived from cancer-associated genes such as TSC1, SPERD2, and CCND2 Furthermore, IPAFinder revealed that IpA could be regulated by factors related to splicing and m6A modification. In summary, IPAFinder enables the global discovery and characterization of biologically regulated IpA with standard RNA-seq data and should reveal the biological significance of IpA in various processes.
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Neoplasias , Poliadenilación , Humanos , Intrones/genética , Neoplasias/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , RNA-SeqRESUMEN
OBJECTIVES: Mitochondrial mutations in HIV-exposed uninfected (HEU) infants after cessation of ART are rarely studied. We analysed a group of HEU newborns born to mothers with late HIV diagnosis who received three doses of ART immediately after birth. We observed mitochondrial DNA (mtDNA) mutations at different times of withdrawal. METHODS: The study was based on a clinical trial conducted from 2015 to 2020. Newborns of the intervention group who met the criteria for this study received triple antiretroviral drugs, zidovudineâ+âlamivudineâ+ânevirapine, within 2 h after the birth, as post-partum prophylaxis, and at 14 days were switched to zidovudineâ+âlamivudineâ+âlopinavir/ritonavir, which was continued until 6 weeks of age. From August to November 2019, blood samples from HEU infants were also collected after ceasing 12 months of ART, and analysed for mtDNA. RESULTS: Our study found that mtDNA mutations remained prevalent in HEU infants a few years after three ARTs were stopped immediately after birth. Among them, D-loop, ND1 and CYTB are the first three mutated regions during different withdrawal periods. This pattern of mutations is similar to, but not exactly consistent with, HIV-infected children receiving standard ART. CONCLUSIONS: Further studies are needed to determine the effects of these mutations on the development of HEU infants and whether stopping ART leads to the restoration of mitochondrial function.
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Infecciones por VIH , Complicaciones Infecciosas del Embarazo , Lactante , Femenino , Niño , Humanos , Recién Nacido , Embarazo , Zidovudina/uso terapéutico , Lamivudine/uso terapéutico , Infecciones por VIH/prevención & control , Antirretrovirales/uso terapéutico , ADN Mitocondrial/genética , Mutación , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/tratamiento farmacológicoRESUMEN
BACKGROUND: Delta-like ligand 3 (DLL3) is highly expressed on the cell surface of small cell lung cancer (SCLC), one of the most lethal malignancies, but minimally or not in normal tissues, making it an attractive target for SCLC. However, none of the DLL3-targeting antibody-drug conjugates (ADCs) have been approved for SCLC therapy yet. We developed DB-1314, the new anti-DLL3 ADC composed of a novel humanized anti-DLL3 monoclonal antibody (DB131401) conjugated with eight molecules of P1021 (topoisomerase I inhibitor), and described its preclinical profiles. METHODS: The binding epitope for DB131401 and Rovalpituzumab was tested by biolayer interferometry. The binding affinity and specificity of DB-1314 to DLL3 and other homologous proteins were respectively measured by surface plasmon resonance and enzyme-linked immunosorbent assay. Internalization, bystander effects, and antibody-dependent cell-mediated cytotoxicity (ADCC) were assessed by respective assay. DLL3 was quantified by antibodies bound per cell assay and immunohistochemistry. In vitro and in vivo growth inhibition studies were evaluated in SCLC cell lines, and cell line/patient-derived xenograft models. The safety profile was measured in cynomolgus monkeys. RESULTS: DB-1314 induces potent, durable, and dose-dependent antitumor effects in cells in vitro and in cell/patient-derived xenograft models in vivo. The killing activity of DB-1314 mechanically arises from P1021-induced DNA damage, whereby P1021 is delivered and released within tumor cells through DLL3-specific binding and efficient internalization. Bystander effects and ADCC also contribute to the antitumor activity of DB-1314. DB-1314 displays favorable pharmacokinetic and toxicokinetic profiles in rats and cynomolgus monkeys; besides, DB-1314 is well-tolerated at a dose of up to 60 mg/kg in monkeys. CONCLUSIONS: These results suggest that DB-1314 may be a candidate ADC targeting DLL3 for the treatment of DLL3-positive SCLC, supporting further evaluation in the clinical setting.
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Inmunoconjugados , Neoplasias Pulmonares , Proteínas de la Membrana , Carcinoma Pulmonar de Células Pequeñas , Inhibidores de Topoisomerasa I , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Carcinoma Pulmonar de Células Pequeñas/patología , Animales , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Humanos , Inhibidores de Topoisomerasa I/farmacología , Inhibidores de Topoisomerasa I/uso terapéutico , Línea Celular Tumoral , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/antagonistas & inhibidores , Macaca fascicularis , Ensayos Antitumor por Modelo de Xenoinjerto , Ratas , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Femenino , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/farmacología , Ratones , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales/farmacología , BenzodiazepinonasRESUMEN
BACKGROUND: HER3 (ErbB3), a member of the human epidermal growth factor receptor family, is frequently overexpressed in various cancers. Multiple HER3-targeting antibodies and antibody-drug conjugates (ADCs) were developed for the solid tumor treatment, however none of HER3-targeting agent has been approved for tumor therapy yet. We developed DB-1310, a HER3 ADC composed of a novel humanized anti-HER3 monoclonal antibody covalently linked to a proprietary DNA topoisomerase I inhibitor payload (P1021), and evaluate the efficacy and safety of DB-1310 in preclinical models. METHODS: The binding of DB-1310 to Her3 and other HER families were measured by ELISA and SPR. The competition of binding epitope for DB-1310 and patritumab was tested by FACS. The sensitivity of breast, lung, prostate and colon cancer cell lines to DB-1310 was evaluated by in vitro cell killing assay. In vivo growth inhibition study evaluated the sensitivity of DB-1310 to Her3 + breast, lung, colon and prostate cancer xenograft models. The safety profile was also measured in cynomolgus monkey. RESULTS: DB-1310 binds HER3 via a novel epitope with high affinity and internalization capacity. In vitro, DB-1310 exhibited cytotoxicity in numerous HER3 + breast, lung, prostate and colon cancer cell lines. In vivo studies in HER3 + HCC1569 breast cancer, NCI-H441 lung cancer and Colo205 colon cancer xenograft models showed DB-1310 to have dose-dependent tumoricidal activity. Tumor suppression was also observed in HER3 + non-small cell lung cancer (NSCLC) and prostate cancer patient-derived xenograft (PDX) models. Moreover, DB-1310 showed stronger tumor growth-inhibitory activity than patritumab deruxtecan (HER3-DXd), which is another HER3 ADC in clinical development at the same dose. The tumor-suppressive activity of DB-1310 synergized with that of EGFR tyrosine kinase inhibitor, osimertinib, and exerted efficacy also in osimertinib-resistant PDX model. The preclinical assessment of safety in cynomolgus monkeys further revealed DB-1310 to have a good safety profile with a highest non severely toxic dose (HNSTD) of 45 mg/kg. CONCLUSIONS: These finding demonstrated that DB-1310 exerted potent antitumor activities against HER3 + tumors in in vitro and in vivo models, and showed acceptable safety profiles in nonclinical species. Therefore, DB-1310 may be effective for the clinical treatment of HER3 + solid tumors.
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Acrilamidas , Compuestos de Anilina , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias del Colon , Inmunoconjugados , Indoles , Neoplasias Pulmonares , Neoplasias de la Próstata , Pirimidinas , Inhibidores de Topoisomerasa I , Animales , Humanos , Masculino , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular , Epítopos , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Macaca fascicularis/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Receptor ErbB-3 , Inhibidores de Topoisomerasa I/farmacología , Inhibidores de Topoisomerasa I/uso terapéutico , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Circular RNAs (circRNAs) showing unusual expressions have been discovered in pancreatic adenocarcinoma (PAAD). However, the functions and underlying mechanisms of these circRNAs still remain largely unclear. Our current study discovered a notable increase in the expression of circRNA hsa_circ_0002395 (circ_0002395) in both PAAD tissues and cell lines. This up-regulation of circ_0002395 was found to be associated with larger tumor sizes and lymph node metastasis. Furthermore, our findings showed that circ_0002395 facilitated aerobic glycolysis and cell proliferation in PAAD cells by regulating the miR-548c-3p/PDK1 axis. Mechanistically, we identified circ_0002395 as a competing endogenous RNA (ceRNA) that sponged miR-548c-3p, thereby promoting PDK1 expression and aerobic glycolysis, and ultimately resulting in the enhancement of cell proliferation. Our findings found that circ_0002395 promoted proliferation of PAAD cells by enhancing PDK1 expression and aerobic glycolysis by sponging miR-548c-3p.
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Adenocarcinoma , MicroARNs , Neoplasias Pancreáticas , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética , Adenocarcinoma/genética , Neoplasias Pancreáticas/genética , Línea Celular Tumoral , Proliferación Celular , GlucólisisRESUMEN
Osteoarthritis (OA) affects numerous patients worldwide, and there are no approved disease-modifying drugs. Repurposing FDA-approved small molecular drugs could be a promising alternative strategy to treat OA. Disulfiram (DSF), a clinically approved drug for treatment of alcoholism, inhibits inflammasome activation and exhibits a protective role in interleukin-1ß-induced cardiac injury. However, its efficacy in treating OA remains to be explored due to its poor water solubility and stability, which limit its use in OA treatment. Here, the anti-inflammatory effect of DSF is evaluated in vitro, and a double-layer encapsulation approach is developed for intra-articular delivery of DSF for OA treatment in vivo. DSF is loaded into poly(lactic-co-glycolic acid)-based nanoparticles and encapsulated in gelatin methacrylate microgels through a microfluidic device. Results show that DSF effectively inhibits the expression of key inflammatory cytokines in OA chondrocytes, and the double-layer encapsulation approach reduces the burst release of DSF and prolongs its retention time in the in vitro study. Sustained release of DSF from microgels mitigates cartilage inflammation and subchondral bone erosion in a monoiodoacetate-induced rat OA model. This work demonstrates the potential of repurposing FDA-approved drugs for OA treatment and provides a promising platform for intra-articular delivery of small molecules for superior therapeutic effect.
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Cartílago Articular , Microgeles , Nanopartículas , Osteoartritis , Humanos , Ratas , Animales , Disulfiram/farmacología , Osteoartritis/tratamiento farmacológico , Osteoartritis/metabolismo , Citocinas , Cartílago Articular/metabolismoRESUMEN
Synaptotagmin-7 (Syt7) plays direct or redundant Ca2+ sensor roles in multiple forms of vesicle exocytosis in synapses. Here, we show that Syt7 is a redundant Ca2+ sensor with Syt1/Doc2 to drive spontaneous glutamate release, which functions uniquely to activate the postsynaptic GluN2B-containing NMDARs that significantly contribute to mental illness. In mouse hippocampal neurons lacking Syt1/Doc2, Syt7 inactivation largely diminishes spontaneous release. Using 2 approaches, including measuring Ca2+ dose response and substituting extracellular Ca2+ with Sr2+, we detect that Syt7 directly triggers spontaneous release via its Ca2+ binding motif to activate GluN2B-NMDARs. Furthermore, modifying the localization of Syt7 in the active zone still allows Syt7 to drive spontaneous release, but the GluN2B-NMDAR activity is abolished. Finally, Syt7 SNPs identified in bipolar disorder patients destroy the function of Syt7 in spontaneous release in patient iPSC-derived and mouse hippocampal neurons. Therefore, Syt7 could contribute to neuropsychiatric disorders through driving spontaneous glutamate release.
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Trastorno Bipolar/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinaptotagminas/fisiología , Animales , Trastorno Bipolar/genética , Calcio/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Ácido Glutámico/metabolismo , Células HEK293 , Hipocampo/citología , Hipocampo/metabolismo , Humanos , Ratones , Ratones Noqueados , Neuronas/metabolismo , Sinaptotagminas/genéticaRESUMEN
Carbon dioxide (CO2) has been widely used to enhance the recovery of adsorbed hydrocarbons from the organic matter (OM) in shale formations. To reveal the driving force of replacing adsorbed hydrocarbons from OM by CO2, we performed molecular dynamics (MD) simulations of the replacement process and calculated the interaction forces between CO2 and hydrocarbons. In addition, based on the umbrella sampling method, steered MD simulations were performed, and the free energy profiles of hydrocarbons were obtained using the weighted histogram analysis method. Results show that the condition of the hydrocarbon replacement by CO2 requires the hydrocarbon to have sufficient kinetic energy or to have a sufficiently large attractive force exerted to ensure that the hydrocarbon escapes the potential well of the OM. The attractive forces exerted on hydrocarbon molecules by CO2 can significantly decrease the energy barrier associated with hydrocarbon movement away from the OM surface. Furthermore, both CO2 and supercritical CO2 can effectively displace adsorbed hydrocarbon gas (methane) on the OM, while supercritical CO2 is required to enhance the recovery of adsorbed hydrocarbon oil (n-dodecane). The results obtained in this study provide guidance for enhancing the recovery of adsorbed hydrocarbons by CO2 in shale formations.
RESUMEN
Guided by the Global Natural Products Social (GNPS) molecular networking strategy, five undescribed eremophilane-type sesquiterpenoid derivatives (1-5) were isolated and identified from fungus Penicillium roqueforti, which was separated from the root soil of plant Hypericum beanii collected in Shennongjia Forestry District, Hubei Province. Dipeniroqueforins A-B (1-2), representing a lactam-type sesquiterpenoid skeleton with a highly symmetrical and homodimeric 5/6/6-6/6/5 hexacyclic system, are reported within the eremophilane-type family for the first time. Peniroqueforin D (5) represents the first example of a 1,2-seco eremophilane-type sesquiterpenoid derivative featuring an undescribed 7/6-fused ring system. The structures of these compounds were elucidated by various spectroscopic analyses, DP4+ probability analyses, ECD calculations, and single-crystal X-ray diffraction experiments. Furthermore, these isolates were evaluated for cytotoxicity, and the result uncovered that compound 1 displayed broad-spectrum activity. Further mechanistic study revealed that compound 1 could significantly upregulate the mRNA expression of genes related to the oxidative induction, leading to the abnormal ROS levels in tumor cells and ultimately causing tumor cell apoptosis.
Asunto(s)
Antineoplásicos , Penicillium , Sesquiterpenos , Sesquiterpenos Policíclicos , Estructura Molecular , Sesquiterpenos/química , Penicillium/química , Antineoplásicos/químicaRESUMEN
Species identification of biological specimens can provide the valuable clues and accelerate the speed of prosecution material processing for forensic investigation, especially when the case scene is inaccessible and the physical evidence is cumbersome. Thus, establishing a rapid, simple, and field-adapted species identification method is crucial for forensic scientists, particularly as first-line technology at the crime scene for initial rapid screening. In this study, we established a new field-adapted species identification method by combining multiplex multienzyme isothermal rapid amplification (MIRA), lateral flow dipstick (LFD) system, and universal primers. Universal primers targeting COX I and COX II genes were used in multiplex MIRA-LFD system for seven species identification, and a dedicated MIRA-LFD system primer targeting CYT B gene was used to detect the human material. DNA extraction was performed by collecting DNA directly from the centrifuged supernatant. Our study found that the entire amplification process took only 15 min at 37 °C and the results of LFDs could be visually observed after 10 min. The detection sensitivity of human material could reach 10 pg, which is equivalent to the detection of single cell. Different common animal samples mixed at the ratio of 1 ng:1 ng, 10 ng:1 ng, and 1 ng:10 ng could be detected successfully. Furthermore, the damaged and degraded samples could also be detected. Therefore, the convenient, feasible, and rapid approach for species identification is suitable for popularization as first-line technology at the crime scene for initial rapid screening and provides a great convenient for forensic application.