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BACKGROUND: Pancreatic adenocarcinomas (PAADs) often exhibit a "cold" or immunosuppressive tumor milieu, which is associated with resistance to immune checkpoint blockade therapy; however, the underlying mechanisms are incompletely understood. Here, we aimed to improve our understanding of the molecular mechanisms occurring in the tumor microenvironment and to identify biomarkers, therapeutic targets, and potential drugs to improve PAAD treatment. METHODS: Patients were categorized according to immunologically hot or cold PAAD subtypes with distinct disease outcomes. Cox regression and weighted correlation network analysis were performed to construct a novel gene signature, referred to as 'Downregulated in hot tumors, Prognostic, and Immune-Related Genes' (DPIRGs), which was used to develop prognostic models for PAAD via machine learning (ML). The role of DPIRGs in PAAD was comprehensively analyzed, and biomarker genes able to distinguish PAAD immune subtypes and predict prognosis were identified by ML. The expression of biomarkers was verified using public single-cell transcriptomic and proteomic resources. Drug candidates for turning cold tumors hot and corresponding target proteins were identified via molecular docking studies. RESULTS: Using the DPIRG signature as input data, a combination of survival random forest and partial least squares regression Cox was selected from 137 ML combinations to construct an optimized PAAD prognostic model. The effects and molecular mechanisms of DPIRGs were investigated by analysis of genetic/epigenetic alterations, immune infiltration, pathway enrichment, and miRNA regulation. Biomarkers and potential therapeutic targets, including PLEC, TRPV1, and ITGB4, among others, were identified, and the cell type-specific expression of the biomarkers was validated. Drug candidates, including thalidomide, SB-431542, and bleomycin A2, were identified based on their ability to modulate DPIRG expression favorably. CONCLUSIONS: By combining multiple ML algorithms, we developed a novel prognostic model with excellent performance in PAAD cohorts. ML also proved to be powerful for identifying biomarkers and potential targets for improved PAAD patient stratification and immunotherapy.
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Adenocarcinoma , Biomarcadores de Tumor , Regulación Neoplásica de la Expresión Génica , Aprendizaje Automático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/inmunología , Biomarcadores de Tumor/metabolismo , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/inmunología , Adenocarcinoma/metabolismo , Pronóstico , Simulación del Acoplamiento Molecular , Microambiente Tumoral , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Masculino , Transcriptoma/genética , FemeninoRESUMEN
Tumor mutation burden (TMB) is a potential biomarker for evaluating the prognosis and response to immune checkpoint inhibitors, but its costly and time-consuming method of measurement limits its widespread application. This study aimed to identify the TMB-related histopathologic features from hematoxylin and eosin slides and explore their prognostic value in gliomas. TMB-related features were detected using a graph convolutional neural network from whole-slide images of patients from The Cancer Genome Atlas data set (619 patients), and the correlation between features and TMB was evaluated in an external validation set (237 patients). TMB-related features were used for predicting overall survival (OS) of patients to investigate whether these features have potential for prognostic prediction. Moreover, biological pathways underlying the prognostic value of the features were further explored. Histopathologic features derived from whole-slide images were significantly associated with patient TMB (P = 0.007 in the external validation set). TMB-related features showed excellent performance for OS prediction, and patients with lower-grade gliomas could be further stratified into different risk groups according to the features (P = 0.00013; hazard ratio, 4.004). Pathways involved in the cell cycle and execution of immune response were enriched in patients with higher OS risk. The TMB-related features could be used to estimate TMB and aid in prognostic risk stratification of patients with glioma with dysregulated biological pathways.
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Aprendizaje Profundo , Glioma , Humanos , Glioma/genética , Ciclo Celular , División Celular , Mutación , Biomarcadores de Tumor , PronósticoRESUMEN
Mimicry is the phenomenon in which one species (the mimic) closely resembles another (the model), enhancing its own fitness by deceiving a third party into interacting with it as if it were the model. In plants, mimicry is used primarily to gain fitness by withholding rewards from mutualists or deterring herbivores cost-effectively. While extensive work has been documented on putative defence mimicry, limited investigation has been conducted in the field of chemical mimicry. In this study, we used field experiments, chemical analyses, behavioural assays, and electrophysiology, to test the hypothesis that the birthwort Aristolochia delavayi employs chemical mimicry by releasing leaf scent that closely resembles stink bug defensive compounds and repels vertebrate herbivores. We show that A. delavayi leaf scent is chemically and functionally similar to the generalized defensive volatiles of stink bugs and that the scent effectively deters vertebrate herbivores, likely through the activation of TRPA1 channels via (E)-2-alkenal compounds. This study provides an unequivocal example of chemical mimicry in plants, revealing intricate dynamics between plants and vertebrate herbivores. Our study underscores the potency of chemical volatiles in countering vertebrate herbivory, urging further research to uncover their potentially underestimated importance.
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Aristolochia , Heterópteros , Animales , Herbivoria , Aristolochia/química , Aristolochia/fisiología , Heterópteros/fisiología , Vertebrados , PlantasRESUMEN
The sustained release of profibrotic cytokines, mainly transforming growth factor-ß (TGF-ß), leads to the occurrence of kidney fibrosis and chronic kidney disease (CKD). Connective tissue growth factor (CTGF) appears to be an alternative target to TGF-ß for antifibrotic therapy in CKD. In this study, we found that long noncoding RNA AI662270 was significantly increased in various renal fibrosis models. In vivo, ectopic expression of AI662270 alone was sufficient to activate interstitial fibroblasts and drive kidney fibrosis, whereas inhibition of AI662270 blocked the activation of interstitial fibroblasts and ameliorated kidney fibrosis in various murine models. Mechanistic studies revealed that overexpression of AI662270 significantly increased CTGF product, which was required for the role of AI662270 in driving kidney fibrosis. Furthermore, AI662270 binds to the CTGF promoter and directly interacts with METTL3, the methyltransferase of RNA N6 -methyladenosine (m6 A) modification. Functionally, AI662270-mediated recruitment of METTL3 increased the m6 A methylation of CTGF mRNA and consequently enhanced CTGF mRNA stability. In conclusion, our results support that AI662270 promotes CTGF expression at the posttranscriptional stage by recruiting METTL3 to the CTGF promoter and depositing m6 A modifications on the nascent mRNA, thereby, uncovering a novel regulatory mechanism of CTGF in the pathogenesis of kidney fibrosis.
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ARN Largo no Codificante , Insuficiencia Renal Crónica , Animales , Ratones , Factor de Crecimiento del Tejido Conjuntivo/genética , Riñón , Metiltransferasas/genética , ARN Largo no Codificante/genética , ARN Mensajero/genética , Factor de Crecimiento Transformador beta/genéticaRESUMEN
The Sc(OTf)3-catalyzed dearomative [5+1] annulations between readily available 3-aminophenols and O-alkyl ortho-oxybenzaldehydes were developed for synthesis of spiro[chromane-3,1'-cyclohexane]-2',4'-dien-6'-ones. The "two-birds-with-one-stone" strategy was disclosed by the dearomatization of phenols and direct α-C(sp3)-H bond functionalization of oxygen through cascade condensation/[1,5]-hydride transfer/dearomative-cyclization process. In addition, the antifungal activity assay and derivatizations of products were conducted to further enrich the utility of the structure.
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BACKGROUND: Neoadjuvant treatment with a dual anti-human epidermal growth factor receptor 2 (HER2) blockade with pyrotinib and trastuzumab has been shown to be effective for HER2-positive breast cancer. METHODS: The genomic characteristics of 425 cancer-related genes from the archived tumour blocks of 50 patients enrolled in a prospective neoadjuvant pyrotinib and trastuzumab plus chemotherapy clinical trial (ChiCTR1900022293) were assessed by next-generation sequencing (NGS). The relationship between tumour biomarkers and the postoperative pathological complete response (pCR) were explored. RESULTS: Forty-five patients completed neoadjuvant chemotherapy and final surgery, of which 26 (58%) achieved a pCR. Among all driver gene mutations, PIK3CA mutation was screened out for having a significant relationship with the treatment response. The pCR rate of patients with wild-type PIK3CA was significantly higher than patients with mutated PIK3CA (80.8% vs. 26.3%; P = 0.00057), and remained significant after a multiple comparison adjustment (Padjusted = 0.024). We further evaluated the predictive value with logistic regression model of clinical features, genetic biomarkers or both, an AUC of 0.912 (95% CI: 0.827-0.997) was achieved in the integrated model. CONCLUSIONS: Our data suggest that HER2-positive breast cancers with activating mutations in PIK3CA are less likely to benefit from pyrotinib combined with trastuzumab neoadjuvant therapy.
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Neoplasias de la Mama , Humanos , Femenino , Trastuzumab , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Terapia Neoadyuvante , Estudios Prospectivos , Anticuerpos Monoclonales Humanizados , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Fosfatidilinositol 3-Quinasa Clase I/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Resultado del TratamientoRESUMEN
BACKGROUND AND AIMS: Species of the genus Buddleja in Asia are mainly distributed in the Sino-Himalayan region and form a challenging taxonomic group, with extensive hybridization and polyploidization. A phylogenetic approach to unravelling the history of reticulation in this lineage will deepen our understanding of the speciation in biodiversity hotspots. METHODS: For this study, we obtained 80 accessions representing all the species in the Asian Buddleja clade, and the ploidy level of each taxon was determined by flow cytometry analyses. Whole plastid genomes, nuclear ribosomal DNA, single nucleotide polymorphisms and a large number of low-copy nuclear genes assembled from genome skimming data were used to investigate the reticulate evolutionary history of Asian Buddleja. Complex cytonuclear conflicts were detected through a comparison of plastid and species trees. Gene tree incongruence was also analysed to detect any reticulate events in the history of this lineage. KEY RESULTS: Six hybridization events were detected, which are able to explain the cytonuclear conflict in Asian Buddleja. Furthermore, PhyloNet analysis combining species ploidy data indicated several allopolyploid speciation events. A strongly supported species tree inferred from a large number of low-copy nuclear genes not only corrected some earlier misinterpretations, but also indicated that there are many Asian Buddleja species that have been lumped mistakenly. Divergent time estimation shows two periods of rapid diversification (8-10 and 0-3 Mya) in the Asian Buddleja clade, which might coincide with the final uplift of the Hengduan Mountains and Quaternary climate fluctuations, respectively. CONCLUSIONS: This study presents a well-supported phylogenetic backbone for the Asian Buddleja species, elucidates their complex and reticulate evolutionary history and suggests that tectonic activity, climate fluctuations, polyploidization and hybridization together promoted the diversification of this lineage.
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Buddleja , Genoma de Plastidios , Scrophulariaceae , Filogenia , PoliploidíaRESUMEN
Upstream stimuli for myofibroblast activation are of considerable interest for understanding the mechanisms underlying renal fibrosis. Activin B, a member of the TGF-ß family, exists as a homodimer of inhibin subunit beta B (INHBB), but its role in renal fibrosis remains unknown. We found that INHBB expression was significantly increased in various renal fibrosis models and human chronic kidney disease specimens with renal fibrosis. Notably, the increase of INHBB occurred mainly in the tubular epithelial cells (TECs). In vivo, inhibiting INHBB blocked the activation of interstitial fibroblasts and ameliorated the renal fibrosis induced by unilateral ureteral obstruction or ischemia-reperfusion injury, while ectopic expression of INHBB in the TECs was able to activate interstitial fibroblasts and initiate interstitial fibrosis. In vitro, overexpression of INHBB in TECs led to the secretion of activin B, thereby promoting the proliferation and activation of interstitial fibroblasts through activin B/Smad signaling. Furthermore, inhibition of activin B/Smad signaling attenuated the fibrotic response caused by tubular INHBB. Mechanistically, the upregulation of INHBB depended on the transcription factor Sox9 in the injured TECs. Clinical analyses also identified a positive correlation between Sox9 and INHBB expression in human specimens, suggesting the Sox9/INHBB axis as a positive regulator of renal fibrosis. In conclusion, tubule-derived INHBB is implicated in the pathogenesis of renal fibrosis by activating the surrounding fibroblasts in a paracrine manner, thereby exhibiting as a potential therapeutic target. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Fibroblastos/metabolismo , Fibrosis/metabolismo , Subunidades beta de Inhibinas/metabolismo , Animales , Proliferación Celular/fisiología , Fibroblastos/patología , Fibrosis/patología , Humanos , Riñón/metabolismo , Riñón/patología , Ratones Endogámicos C57BL , Miofibroblastos/metabolismo , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/patología , Regulación hacia Arriba , Obstrucción Ureteral/metabolismo , Obstrucción Ureteral/patologíaRESUMEN
Organic-inorganic hybrid materials with switchable properties have significant potential applications in intelligent devices. There are some conventional ways to obtain optical and/or electric multiple responses, such as asymmetric design, chirality, doping, and structural dimension in hybrid materials. Among them, the homochirality strategy is one of the best ways to regulate the molecular structure and symmetry, thereby ensuring second-harmonic generation (SHG) and dielectric dual response characteristics. Here, we report a homochiral design strategy to obtain noncentrosymmetric [R-(HASD)][Cd(SCN)3] (HASD = 7-hydroxy-5-azaspiro[4.5]decan) and [S-(HASD)][Cd(SCN)3]; [Rac-(HASD)][Cd(SCN)3] was also synthesized as a comparative experiment to illustrate the relationship between structural chirality and physical properties. With the help of homochiral regulation, the SHG response is excited and dielectric phase transition temperature (Tc) is also highly improved. In addition, both the optical SHG and dielectric phase change show an optical/electric switchable response. This work is of great significance for the further exploration of multifunctional molecular switching materials through homochiral chemistry.
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OBJECTIVES: To study the value of bedside echocardiography in predicting persistent patency of the ductus arteriosus during the early postnatal period in very low birth weight (VLBW) infants. METHODS: A retrospective analysis was performed for 51 VLBW infants who were admitted from March 2020 to June 2021, with an age of ≤3 days and a length of hospital stay of ≥14 days. According to the diameter of patent ductus arteriosus (PDA) on days 14 and 28 after birth, the infants were divided into three groups: large PDA group (PDA diameter ≥2 mm), small PDA group (PDA diameter <2 mm), and PDA closure group (PDA diameter =0 mm). The echocardiographic parameters measured at 72 hours after birth were compared among the three groups. The receiver operating characteristic (ROC) curve was used to evaluate the value of the echocardiographic parameters in predicting persistent patency of the ductus arteriosus (PDA≥2 mm) at the ages of 14 and 28 days. RESULTS: On day 14 after birth, there were 17 infants in the large PDA group, 11 in the small PDA group, and 23 in the PDA closure group. On day 28 after birth, there were 14 infants in the large PDA group, 9 in the small PDA group, and 26 in the PDA closure group. There were significant differences in gestational age, birth weight, rate of pulmonary surfactant use, and incidence rate of hypotension among the three groups (P<0.05). PDA diameter, end-diastolic velocity of the left pulmonary artery, left ventricular output, and left ventricular output/superior vena cava flow ratio measured at 72 hours after birth were associated with persistent patency of the ductus arteriosus at the ages of 14 and 28 days (P<0.05), and the ratio of the left atrium to aorta diameter was associated with persistent patency of the ductus arteriosus at the age of 28 days (P<0.05). The ROC curve analysis showed that the area under the curve that the PDA diameter measured at 72 hours after birth predicting the persistent patency of the ductus arteriosus at the ages of 14 and 28 days was the largest (0.841 and 0.927 respectively), followed by end-diastolic velocity of the left pulmonary artery, with the area under the curve of 0.793 and 0.833 respectively. CONCLUSIONS: The indicators obtained by beside echocardiography at 72 hours after birth, especially PDA diameter and end-diastolic velocity of the left pulmonary artery, can predict persistent patency of the ductus arteriosus at the ages of 14 and 28 days in VLBW infants, which provides a basis for the implementation of early targeted treatment strategy for PDA.
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Conducto Arterioso Permeable , Conducto Arterioso Permeable/diagnóstico por imagen , Ecocardiografía , Humanos , Lactante , Recién Nacido , Recién Nacido de muy Bajo Peso , Estudios Retrospectivos , Vena Cava SuperiorRESUMEN
Massive efforts have been devoted to designing molecular ferroic materials by molecular modification. For molecular ferroelastic, previous work is focused on the temperature-dependent ferroelastic domains, however, few are related to controlling the ferroelastic domain by the stress. Inspired by the "quasi-spherical theory" and fluorination effect, we designed a more flexible (MedabcoF)2+ (MedabcoF=1-fluoro-4-methyl-1,4-diazoniabicyclo[2.2.2]octane) cation by introducing a methyl group and a fluorine atom at the two symmetrical ends of the Dabco (1,4-diazoniabicyclo[2.2.2]octane) and synthesized a hybrid 3D perovskite (MedabcoF)Rb(BF4 )3 (1) which displays three reversible phase transitions accompanying dual ferroelastic behavior. Besides, it not only exhibits ferroelastic domains switching by the thermal stimulation, and the sensitive reaction of in situ domains under the stress of it is also realized. This work not only achieves a force-controlled ferroelastic domain but develops a more profound comprehension of the relationship between the thermal motion behavior of guest cations and the intriguing properties of materials.
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BACKGROUND: Surgical resection remains the only potentially curative treatment for pancreatic ductal adenocarcinoma (PDAC). However, a number of patients get disease recurred in a short time post-operation. Few studies have focused on the predictors of different recurrence patterns of PDAC. OBJECTIVE: To try to establish and verify a nomogram to predict recurrence free survival (RFS) in PDAC patients, and to distinguish the risk factors of local recurrence first and distant metastasis first via competing risk model. METHODS: Patients who underwent radical pancreatectomy for PDAC in our center from 2010 to 2018 were reviewed retrospectively. Kaplan-Meier methods and multivariate Cox regression analyses were used to identify the clinicopathological predictors of recurrence post-operation. And then, a nomogram was constructed and validated. Competing risk regression model was used to compare the predictors between local recurrence group and distant metastasis group. RESULTS: A total of 200 patients were included into the final analysis, and 153 patients got disease relapsed post-operation. CA19-9 level, vascular resection, tumor differentiation, lymph node ratio (LNR) and adjuvant chemotherapy were identified as independent risk factors for recurrence free survival (RFS) and incorporated into the nomogram. The C-index of the nomogram was 0.650. Competing risk model indicated that the status of lymph-node metastasis was significantly associated the patterns of first relapse. CONCLUSIONS: Nomogram and competing risk model were constructed to quantify the risk of recurrence following surgery for PDAC. Our findings may be useful for predicting RFS and recurrence pattern in clinical work.
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Nucleic acid detection technology based on polymerase chain reaction (PCR) and antibody detection based on immunochromatography still have many problems such as false negatives for the diagnosis of coronavirus disease 2019 (COVID-19). Therefore, it is of great importance to develop new techniques to improve the diagnostic accuracy of COVID-19. We herein developed an ultrasensitive, rapid, and duplex digital enzyme-linked immunosorbent assay (dELISA) for simultaneous detection of spike (S-RBD) and nucleocapsid (N) proteins of SARS-CoV-2 based on a single molecule array. This assay effectively combines magnetic bead encoding technology and the ultrasensitive detection capability of a single molecule array. The detection strategies of S-RBD protein and N-protein exhibited wide response ranges of 0.34-1065 pg/mL and 0.183-338 pg/mL with detection limits of 20.6 fg/mL and 69.8 fg/mL, respectively. It is a highly specific method for the simultaneous detection of S-RBD protein and N-protein and has minimal interference from other blood proteins. Moreover, the spike assay showed a satisfactory and reproducible recovery rate for the detection of S-RBD protein and N-protein in serum samples. Overall, this work provides a highly sensitive method for the simultaneous detection of S-RBD protein and N-protein, which shows ultrasensitivity and high signal-to-noise ratio and contributes to improve the diagnosis accuracy of COVID-19.
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COVID-19/diagnóstico , Proteínas de la Nucleocápside de Coronavirus/aislamiento & purificación , SARS-CoV-2/aislamiento & purificación , Imagen Individual de Molécula/métodos , Glicoproteína de la Espiga del Coronavirus/aislamiento & purificación , Anticuerpos Antivirales/aislamiento & purificación , Proteínas de la Nucleocápside de Coronavirus/genética , Ensayo de Inmunoadsorción Enzimática/normas , Humanos , Inmunoensayo/métodos , Magnetismo , Microesferas , Fosfoproteínas/genética , Fosfoproteínas/aislamiento & purificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/genéticaRESUMEN
Genetically modified (GM) crops possess some superior characteristics, such as high yield and insect resistance, but their biosafety has aroused broad public concern. Some genetic engineering technologies have recently been proposed to remove exogenous genes from GM crops. Few approaches have been applied to maintain advantageous traits, but excising exogenous genes in seeds or fruits from these hybrid crops has led to the generation of harvested food without exogenous genes. In a previous study, split-Cre mediated by split intein could recombine its structure and restore recombination activity in hybrid plants. In the current study, the recombination efficiency of split-Cre under the control of ovule-specific or pollen-specific promoters was validated by hybridization of transgenic Arabidopsis containing the improved expression vectors. In these vectors, all exogenous genes were flanked by two loxP sites, including promoters, resistance genes, reporter genes, and split-Cre genes linked to the reporter genes via LP4/2A. A gene deletion system was designed in which NCre was driven by proDD45, and CCre was driven by proACA9 and proDLL. Transgenic lines containing NCre were used as paternal lines to hybridize with transgenic lines containing CCre. Because this hybridization method results in no co-expression of the NCre and CCre genes controlled by reproduction-specific promoters in the F1 progeny, the desirable characteristics could be retained. After self-crossing in F1 progeny, the expression level and protein activity of reporter genes were detected, and confirmed that recombination of split-Cre had occurred and the exogenous genes were partially deleted. The gene deletion efficiency represented by the quantitative measurements of GUS enzyme activity was over 59%, with the highest efficiency of 73% among variable hybrid combinations. Thus, in the present study a novel dual reproductive cell-specific promoter-mediated gene deletion system was developed that has the potential to take advantage of the merits of GM crops while alleviating biosafety concerns.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Eliminación de Gen , Integrasas/metabolismo , Plantas Modificadas Genéticamente/genética , Regiones Promotoras Genéticas , Transgenes , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Ingeniería Genética , Vectores Genéticos , Integrasas/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/metabolismo , Recombinación Genética , ReproducciónRESUMEN
Piezoelectric sensors that can work under various conditions with superior performance are highly desirable with the arrival of the Internet of Things. For practical applications, a large piezoelectric voltage coefficient g and a high Curie temperature Tc are critical to the performance of piezoelectric sensors. Here, we report a two-dimensional perovskite ferroelectric (4-aminotetrahydropyran)2PbBr4 [(ATHP)2PbBr4] with a saturated polarization of 5.6 µC cm-2, high Tc of 503 K [above that of BaTiO3 (BTO, 393 K)], and extremely large g33 of 660.3 × 10-3 V m N-1 [much beyond that of Pb(Zr,Ti)O3 (PZT) ceramics (20 to 40 × 10-3 V m N-1), more than 2 times higher than that of poly(vinylidene fluoride) (PVDF, about 286.7 × 10-3 V m N-1)]. Combined with the advantages of molecular ferroelectrics, such as light weight, easy and environmentally friendly processing, and mechanical flexibility, (ATHP)2PbBr4 would be a competitive candidate for next-generation smart piezoelectric sensors in flexible devices, soft robotics, and biomedical devices.
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In this work, a label-free and highly sensitive fluorescence assay was constructed for microRNA detection. Nicking-enhanced rolling circle amplification (RCA) induced by G-quadruplex formation is coupled with inner filter effect (IFE)-based quenching effects of MoS2 quantum dots (MoS2 QDs). The padlock probe contains a recognition sequence to target microRNA and an accessible nicking site. The padlock probe is cyclized upon hybridization with target microRNA. Sequentially, amplification initiates a production of a long-concatenated sequence of circular probes. Abundant G-quadruplex sequences are produced via the nicking process and then used as the trigger to initiate the next RCA. In the presence of hemin, numerous hemin/G-quadruplex DNAzymes are formed, which catalyze the oxidation of o-phenylenediamine (OPD) into the colored product 2,3-diaminophenazine, resulting in quenching of the fluorescence of MoS2 QDs. This sensing strategy enables detection of microRNA let-7a with high selectivity and a detection limit of 4.6 fM. The as-prepared sensor was applied for detecting microRNA let-7a in dilute human serum samples and achieved a satisfactory recovery rate, demonstrating its potential in clinic diagnosis of microRNA-associated disease and biochemical research.
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Disulfuros/química , MicroARNs/sangre , MicroARNs/genética , Molibdeno/química , Técnicas de Amplificación de Ácido Nucleico , Puntos Cuánticos/química , Disulfuros/síntesis química , HumanosRESUMEN
BACKGROUND: The nuclear transport system has been proposed to be indispensable for cell proliferation and invasion in cancers. Prognostic biomarkers and molecular targets in nuclear transport systems have been developed. However, no systematic analysis of genes related to nuclear transport in gliomas has been performed. An integrated prognostic classification involving mutation and nuclear transport gene signatures has not yet been explored. METHODS: In the present study, we analyzed gliomas from a training cohort (TCGA dataset, n = 660) and validation cohort (CGGA dataset, n = 668) to develop a prognostic nuclear transport gene signature and generate an integrated classification system. Gene set enrichment analysis (GSEA) showed that glioblastoma (GBM) was mainly enriched in nuclear transport progress compared to lower-grade glioma (LGG). Then, we developed a nuclear transport risk score (NTRS) for gliomas with a training cohort. NTRS was significantly correlated with clinical and genetic characteristics, including grade, age, histology, IDH status and 1p/19q codeletion, in the training and validation cohorts. RESULTS: Survival analysis revealed that patients with a higher NTRS exhibited shorter overall survival. NTRS showed better prognostic value compared to classical molecular markers, including IDH status and 1p/19q codeletion. Furthermore, univariate and multivariate analyses indicated that NTRS was an independent prognostic factor for gliomas. Enrichment map and Gene Ontology analysis demonstrated that signaling pathways related to the cell cycle were enriched in the NTRSHigh group. Subgroup survival analysis revealed that NTRS could differentiate the outcomes of low- and high-risk patients with wild-type IDH or mutant IDH and 1p/19q non-codeletion. CONCLUSIONS: NTRS is associated with poor outcomes and could be an independent prognostic marker in diffuse gliomas. Prognostic classification combined with IDH mutation, 1p/19q codeletion and NTRS could better predict the survival of glioma patients.
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Transporte Activo de Núcleo Celular/genética , Biomarcadores de Tumor/genética , Deleción Cromosómica , Glioma/patología , Isocitrato Deshidrogenasa/genética , Mutación , Transcriptoma , Adolescente , Adulto , Anciano , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Niño , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 19/genética , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Glioma/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia , Adulto JovenRESUMEN
BACKGROUND: Tumor mutational burden (TMB) is a potential biomarker for immune checkpoint therapy and prognosis. The impact of TMB on clinical outcomes and the correlation coefficient between exome sequencing and targeted sequencing in glioma have not yet been explored. METHODS: Somatic mutations in the coding regions of 897 primary gliomas and the clinical and RNA-seq data of 654 patients in The Cancer Genome Atlas (TCGA) database were analyzed as a training set, while another 286 patients in the Chinese Glioma Genome Atlas (CGGA) database were used for validation. Descriptive and correlational analyses were conducted with TMB. Enrichment map analysis and gene set enrichment analysis (GSEA) were also performed. RESULTS: TMB was higher for the group of mutant genes that are frequently mutated in glioblastomas (GBMs) and lower for the group of mutant genes that are frequently mutated in lower-grade gliomas (LGGs). Patients with a higher TMB exhibited shorter overall survival. TMB was associated with grade, age, subtype and mutations affecting genomic structure. Moreover, univariate and multivariate analyses showed that TMB was an independent prognostic factor for glioma. The signaling pathways of the cell cycle were enriched in the TMBHigh group. TMB was higher in the mismatch repair (MMR) gene mutant group than in the wild-type group, but the MMR pathway was enriched in the TMBHigh group of gliomas without mutations in classical MMR genes. The correlation between TMBs calculated through exome sequencing and targeted sequencing was moderate, and panel-based TMB was not correlated with prognosis. CONCLUSIONS: TMB is associated with poor outcomes in diffuse glioma. The high proliferative activity in the TMBHigh group could account for the shorter survival of these patients. This association was not reflected by a pan-cancer targeted sequencing panel.
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Neoplasias Encefálicas/genética , Redes Reguladoras de Genes , Glioma/genética , Mutación , Femenino , Humanos , Masculino , Pronóstico , Análisis de Secuencia de ARN , Análisis de Supervivencia , Secuenciación del ExomaRESUMEN
Activatable aptamer probes (AAPs) are promising in molecular imaging of tumors, but the reported shape-switching-dependent AAPs are still challenged by unsatisfied noise suppression, poor stability, and sophisticated sequence design. To address the problem, we constructed a pH-activatable aptamer probe (pH-AAP) by utilizing an acid-labile acetal linker as the responsive element to be fused with a tumor-targeted aptamer. Specifically, a Cy5-labeled aptamer was connected with the quencher BHQ2 through the acetal group, thus generating pH-AAP with quenched fluorescence. Due to the stable proximity of Cy5 to BHQ2, pH-AAP was found to have ultralow background with a quenching efficiency as high as 98%. In comparison with shape-switching-dependent AAPs, the noise suppression of pH-AAP was well maintained for a much longer time in both serum and mouse body, thus showing a robust fluorescence stability. By a combination of the fluorescence recovery induced by acid hydrolysis of acetal linkers and the tumor-targeted recognition of aptamers, pH-AAP could either specifically anchor the extracellular pH-activated signals on the target cell surface in an acidic tumor microenvironment or be activated by acidic lysosomes after it was internalized into target cells. As proof of concept, in vitro evaluation and in vivo imaging of A549 lung cancer cells were performed by using S6 aptamer as a demonstration. It was indicated that pH-AAP realized washing-free, bispecific, and contrast-enhanced tumor imaging. The strategy is simple and free of sequence modification, which promises to provide a universal platform for sensitive and precise tumor diagnosis.
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Aptámeros de Nucleótidos/química , Colorantes Fluorescentes/química , Neoplasias/diagnóstico por imagen , Animales , Aptámeros de Nucleótidos/síntesis química , Carbocianinas/química , Línea Celular Tumoral , Colorantes Fluorescentes/síntesis química , Humanos , Concentración de Iones de Hidrógeno , Lisosomas/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Imagen Óptica/métodos , Prueba de Estudio Conceptual , Microambiente Tumoral/fisiologíaRESUMEN
We present herein a compact terahertz (THz) spectrometer in which transmission intensity distribution associated with dispersive interference effects in disordered random surfaces are used for reconstructing the frequency contents of an incoming THz beam. The device sweeps the frequency-dependent parameter of a roughened transmission plate through lateral displacement or electro-optic modulation. 2D transmission intensities are sequentially captured by a single detector for a range of modulation depths. With a calibration data set as the reference, one can reconstruct the spectra of the probe THz beam by solving a system of simultaneous linear equations. A smoothing Tikhonov regularization approach has been implemented to improve the accuracy of the spectral reconstruction. The reported compact, broadband, high-resolution THz spectrometer is well suited for portable THz spectroscopy applications.