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The recent discoveries of two-dimensional (2D) magnets1-6 and their stacking into van der Waals structures7-11 have expanded the horizon of 2D phenomena. One exciting application is to exploit coherent magnons12 as energy-efficient information carriers in spintronics and magnonics13,14 or as interconnects in hybrid quantum systems15-17. A particular opportunity arises when a 2D magnet is also a semiconductor, as reported recently for CrSBr (refs. 18-20) and NiPS3 (refs. 21-23) that feature both tightly bound excitons with a large oscillator strength and potentially long-lived coherent magnons owing to the bandgap and spatial confinement. Although magnons and excitons are energetically mismatched by orders of magnitude, their coupling can lead to efficient optical access to spin information. Here we report strong magnon-exciton coupling in the 2D A-type antiferromagnetic semiconductor CrSBr. Coherent magnons launched by above-gap excitation modulate the exciton energies. Time-resolved exciton sensing reveals magnons that can coherently travel beyond seven micrometres, with a coherence time of above five nanoseconds. We observe these exciton-coupled coherent magnons in both even and odd numbers of layers, with and without compensated magnetization, down to the bilayer limit. Given the versatility of van der Waals heterostructures, these coherent 2D magnons may be a basis for optically accessible spintronics, magnonics and quantum interconnects.
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Skyrmion racetrack memories are highly attractive for next-generation data storage technologies. Skyrmions are noncollinear spin textures stabilized by chiral interactions. To achieve a fast-operating memory device, it is critical to move skyrmions at high speeds. The skyrmion dynamics induced by spin-orbit torques (SOTs) in the commonly studied ferromagnetic films is hindered by strong pinning effects and a large skyrmion Hall effect causing deflection of the skyrmion toward the racetrack edge, which can lead to information loss. Here, we investigate the current-induced nucleation and motion of skyrmions in ferrimagnetic Pt/CoGd/(W or Ta) thin films. We first reveal field-free skyrmion nucleation mediated by Joule heating. We then achieve fast skyrmion motion driven by SOTs with velocities as high as 610 m s-1 and a small skyrmion Hall angle |θSkHE| â² 3°. Our results show that ferrimagnets are better candidates for fast skyrmion-based memory devices with low risk of information loss.
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In this work, nitrogen-rich linear porous organic polymers (POPs) were designed to improve glycopeptides enrichment efficiency in HILIC. Two kinds of novel POPs (CH-pPAL and CH-mPAL) were one-step prepared via the Schiff-base condensation reaction and intermolecular hydrogen-bonded using a flexible amine monomer (carbohydrazide, CH) to react with two aldehyde monomers, p-phthalaldehyde (pPAL) and m-phthalaldehyde (mPAL), respectively. The specific surface area of CH-pPAL and CH-mPAL was 238 and 232 m2 g-1, respectively. Based on the hydrogen-bond interaction, several narrow peaks existed in the PXRD patterns. Particularly, micron-sized spherical CH-pPAL possessed a honeycomb-like orderly tunnel structure. The contact angle of CH-pPAL and CH-mPAL severally was 35.4° and 28.8°, respectively, indicating excellent hydrophilicity of as-synthesized POPs. They both demonstrated high sensitivity and high adsorption capacity in glycopeptides enrichment. The 851 and 794 unique glycopeptides derived from 170 and 200 N-glycosylated proteins were identified after the enrichment by CH-pPAL and CH-mPAL within three independent replicates of proteins extracted from human serum, respectively. Therefore, these CH-based hydrophilic POP materials would be applied in the enrichment and identification of low-abundance N-linked glycopeptides from complicated biological samples.
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Glicopéptidos , Polímeros , Glicopéptidos/química , Humanos , Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Nitrógeno , Polímeros/química , PorosidadRESUMEN
Pancreatic cancer has led to an extremely high mortality rate because of its insidious onset and lack of early clinical symptoms. Effective early diagnosis is essential to improve the treatment of pancreatic cancer. Tumor-secreted extracellular vesicles (EVs) have attracted great interest as potential tumor biomarkers. However, most of the methods for detecting serum EVs have some general problems such as cumbersome, time-consuming extraction steps, and high cost, which limit greatly the research on cancer detection based on EVs. Herein, we report a light-initiated chemiluminescent assay (LICA) method using photosensitive beads for direct detection of EVs in serum enriched with ephrin type-A receptor 2 (EphA2), which show high expression in pancreatic cancer patients. Combining with a serum biomarker CA19-9, pancreatic cancer patients could be distinguished rapidly by sensitive detection of EphA2-EVs from serum without any purification. This developed method could be extended to improve the diagnosis efficiency for other cancers and gain an insight into EV detection.
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Vesículas Extracelulares , Neoplasias Pancreáticas , Biomarcadores de Tumor/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Mediciones Luminiscentes , Páncreas , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/metabolismoRESUMEN
Bladder cancer (BC) is one of the most common cancers in the world, with high morbidity and mortality. It is essential to develop a non-invasive, highly accurate, and simple method for BC diagnosis. This work proposed a fluorescent biosensor based on inorganic nanoflares combined with a DNAzyme walker for the simultaneous detection of BC exosomal microRNAs (miRNAs). This biosensor was constructed on the Au nanoparticle (AuNP) modified with the carbon dot (CD)-labeled substrates and DNAzyme strands (AuNP@CDs inorganic nanoflares-DNAzyme, APCD). In the presence of target miRNAs, DNAzyme was activated and then cleaved the CD-labeled substrates and automatically walked along the AuNP, allowing fluorescence recovery. Due to the structure and functional composition, the APCD biosensors demonstrated high sensitivity and specificity, with the reached limit of detection for a single miRNA at the femtomolar level and wide linear range from 50 fM to 10 nM. Furthermore, the simultaneous analysis of BC-related exosomal miR-133b and miR-135b in clinical serum specimens was achieved and consistent with qRT-PCR, suggesting it is a potential method for the diagnosis of BC and other cancers.
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Técnicas Biosensibles , ADN Catalítico , Nanopartículas del Metal , MicroARNs , Neoplasias de la Vejiga Urinaria , Técnicas Biosensibles/métodos , ADN Catalítico/química , Oro/química , Humanos , Límite de Detección , Nanopartículas del Metal/química , MicroARNs/análisis , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/genéticaRESUMEN
Ferrimagnetic thin films are attractive for low-power spintronic applications because of their low magnetization, small angular momentum, and fast spin dynamics. Spin orbit torques (SOT) can be applied with proximal heavy metals that also generate interfacial Dzyaloshinskii-Moriya interactions (DMI), which can stabilize ultrasmall skyrmions and enable fast domain wall motion. Here, the properties of a ferrimagnetic CoGd alloy between two heavy metals to increase the SOT efficiency, while maintaining a significant DMI is studied. SOT switching for various capping layers and alloy compositions shows that Pt/CoGd/(W or Ta) films enable more energy-efficient SOT magnetization switching than Pt/CoGd/Ir. Spin-torque ferromagnetic resonance confirms that Pt/CoGd/W has the highest spin-Hall angle of 16.5%, hence SOT efficiency, larger than Pt/CoGd/(Ta or Ir). Density functional theory calculations indicate that CoGd films capped by W or Ta have the largest DMI energy, 0.38 and 0.32 mJ m-2 , respectively. These results show that Pt/CoGd/W is a very promising ferrimagnetic structure to achieve small skyrmions and to move them efficiently with current.
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In a spintronic resonator a radio-frequency signal excites spin dynamics that can be detected by the spin-diode effect. Such resonators are generally based on ferromagnetic metals and their responses to spin torques. New and richer functionalities can potentially be achieved with quantum materials, specifically with transition metal oxides that have phase transitions that can endow a spintronic resonator with hysteresis and memory. Here we present the spin torque ferromagnetic resonance characteristics of a hybrid metal-insulator-transition oxide/ ferromagnetic metal nanoconstriction. Our samples incorporate [Formula: see text], with Ni, Permalloy ([Formula: see text]) and Pt layers patterned into a nanoconstriction geometry. The first order phase transition in [Formula: see text] is shown to lead to systematic changes in the resonance response and hysteretic current control of the ferromagnetic resonance frequency. Further, the output signal can be systematically varied by locally changing the state of the [Formula: see text] with a dc current. These results demonstrate new spintronic resonator functionalities of interest for neuromorphic computing.
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In this study, a commercial and low-toxicity hydrazide-containing building block has been used to construct azine-linked covalent organic frameworks (COFs). New style COFs were constructed between flexible formic hydrazide (FH) and 1,3,5-triformylphloroglucinal (Tp) or 1,3,5-triformylbenzene (TFB). The two resulting COFs (TpFH and TFBFH) exhibited uniform hollow tubular morphology (20-50 nm for TpFH, 50-100 nm for TFBFH). Compared to hydrazine, FH has low-toxicity and is a flexible monomer, consisting of amine and aldehyde groups. The decomposition of FH slows down the reaction rate and the as-synthesized FH-series COFs (708 m2 g-1 for TpFH and 888 m2 g-1 for TFBFH) had higher specific surface area than hydrazine-series COFs (617 m2 g-1 for TpAzine and 472 m2 g-1 for TFBAzine). A detailed time-dependent investigation was carried out to interpret the mechanism of hollow structure formation, and Ostwald ripening possibly happens during the formation of hollow COF microstructures. Considering the porous and high density N, O elements of these materials, preliminary applications of the metal ions removal from aqueous solution and gas storage were implemented.
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Bladder Cancer (BC) is the ninth most common tumor in the world and one of the most common malignant tumors of the urinary system. Some studies reported that miR-133b expression is reduced in BC, but whether it plays a role in the development of BC and its mechanism is unclear. microRNAs can be packaged into exosomes to mediate communication between tumor cells, affecting their proliferation and apoptosis. The objective of this study was to investigate the effect of exosomal miR-133b on BC proliferation and its molecular mechanism. Firstly, the expression of miR-133b was evaluated in BC and adjacent normal tissues, as well as in serum exosomes of BC patients and healthy controls. Then the delivery and internalization of exosomes in cells was observed through fluorescence localization. Cell viability and apoptosis were assessed in BC cells transfected with mimics and incubated with exosomes. The role of exosomal miR-133b was also analyzed in nude mice transplant tumors. Furthermore, the target gene of miR-133b was predicted through bioinformatics. The level of miR-133b was significantly decreased in BC tissues and in exosomes from serum of patients, which was correlated with poor overall survival in TCGA. Exosomal miR-133b could be obtained using BC cells after transfection with miR-133b mimics. The miR-133b expression increased after incubation with exosomal miR-133b, which lead to the inhibition of viability and increase of apoptosis in BC cells. Exosomal miR-133b could suppress tumor growth in vivo. In addition, we found that exosomal miR-133b may play a role in suppressing BC proliferation by upregulating dual-specificity protein phosphatase 1 (DUSP1). These findings may offer promise for new therapeutic directions of BC.
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Proliferación Celular , Fosfatasa 1 de Especificidad Dual/metabolismo , Exosomas/metabolismo , MicroARNs/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Anciano , Animales , Apoptosis , Comunicación Celular , Supervivencia Celular , Regulación hacia Abajo , Femenino , Humanos , Masculino , Ratones , Ratones Desnudos , MicroARNs/sangre , Fenotipo , Pronóstico , Tasa de Supervivencia , Regulación hacia Arriba , Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/sangre , Neoplasias de la Vejiga Urinaria/mortalidadRESUMEN
To investigate lncRNAs acting as competing endogenous RNAs (ceRNAs) involved in oncogenesis and progression of HCC. Different expressed lncRNAs, microRNAs, and mRNAs (DElncRNAs, DEmiRNAs, DEmRNAs), downloaded from The Cancer Genome Atlas (TCGA) database, were identified by edgeR package. CeRNA network was constructed based on miRcode, TargetScan, and miRTarBase. Target DEmRNAs were annotated by KEGG pathway and GO analysis. Negatively correlated lncRNA-miRNA pairs were analyzed by Pearson correlation coefficient, simultaneously, overall survival (OS) were evaluated. The expression of these lncRNAs were examined in HCC cell lines and tissues through qRT-PCR. 1070 DElncRNAs, 147 DEmiRNAs and 1993 DEmRNAs were acquired. CeRNA network was successfully established, including 27 lncRNAs, 5 miRNAs, and 30 mRNAs significantly correlated with OS. The DEmRNAs were significantly enriched in "Cell Cycle" and "pathways in cancer". Six lncRNAs and 2 miRNAs were negatively correlated. These lncRNAs were validated by qRT-PCR. These observations will provide a novel perspective to elucidate HCC pathogenesis.
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Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , MicroARNs/genética , ARN Largo no Codificante/genética , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Bases de Datos Genéticas , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Clasificación del Tumor , Pronóstico , Análisis de SupervivenciaRESUMEN
An important goal of spintronics is to covert a charge current into a spin current with a controlled spin polarization that can exert torques on an adjacent magnetic layer. Here we demonstrate such torques in a two ferromagnet system. A CoNi multilayer is used as a spin current source in a sample with structure CoNi/Au/CoFeB. Spin torque ferromagnetic resonance is used to measure the torque on the CoFeB layer. The response as a function of the applied field angle and current is consistent with the symmetry expected for a torque produced by the planar Hall effect originating in CoNi. We find the strength of this effect to be comparable to that of the spin Hall effect in platinum, indicating that the planar Hall effect holds potential as a spin current source with a controllable polarization direction.
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A novel porous organic cage (POC) was prepared via condensation reaction between 1,3,5-triformylbenzene (TFB) and (1R,2R)-4-cyclohexene-1,2-diamine (CHEDA). This POC could pack in either an amorphous structure or a crystalline one. Atomically precise structure determination of POC was achieved through ab initio powder X-ray diffraction (PXRD) structure analysis in the chiral trigonal space group R3. The same atomically precise structure determination of POC from single-crystal X-ray diffraction (SXRD) structure analysis could be obtained independently with a slight difference in cell parameter, indicating that the refinement method through ab initio PXRD structure analysis is reliable and may serve as an essential method for atomically precise structure determination. The cage could adsorb up to 8 mmol/g CO2 at 298 K and 1 bar. Furthermore, 1-thioglycerol and 1-octadecanethiol were chosen to prove that postmodification of this POC was flexible. After post-synthetic modification (PSM) via highly efficient photoinitiated thiol-ene click reaction, the products still kept porous with relatively higher special surface area (337 m2/g of 5T and 156 m2/g of 5O) than mostly reported cages via the reduced-amine approach.
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Although capillary liquid chromatography married with tandem mass spectrometry (cLC-MS/MS) has become a powerful technique for proteomics and metabolomics research, it is still a great challenge to fabricate durable capillary-based analytical columns coupling continuous nanoflow (<1â¯000 nL/min) electrospray ionization (ESI) with MS, owing to the issue of clogging and fragile of emitters. Here, we proposed a simple approach to integrate microstructured photonic fibers (MPFs) into wide bore capillaries with 150 µm i.d., serving as an integral bifunctional frit or/and ESI emitter of packed columns. Two kinds of MPFs containing 126 homogeneous microchannels with different inner diameter, 3.2 µm for MPF-1 and 2.6 µm for MPF-2, were explored for preparation. The octadecylsilicate (ODS) silica-packed column using MPF-1 as a frit exhibited the lowest plate heights of 14.2-19.7 µm for five alkylbenzenes at the velocity of 1.5 mm/s, which were slightly lower than those of packed column with porous polymer monolith (PPM)-based frit by cLC coupling with ultraviolet (UV) detection. Additionally, the packed columns with integral MPF frit-emitters were further applied in analysis of a complex biological sample of digest of Hela cells by cLC-MS. An average of 7109 unique peptides could be identified in a single analysis by using MPF-1 emitter, and 7110 unique peptides were identified by using the MPF-2 emitter, which were superior to the identified result of packed column with an integral tapered tip emitter (6894 peptides). It is obvious that this novel integral MPF-based frit-emitter does not easily suffer from the issues of cracking owing to the silica cladding around independent microchannels (>100), which always encumbers both independent and integral tapered tip emitters for cLC-MS.
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Fibras Ópticas , Péptidos/análisis , Fotones , Proteínas/análisis , Cromatografía Liquida , Células HeLa , Humanos , Tamaño de la Partícula , Espectrometría de Masa por Ionización de Electrospray , Propiedades de Superficie , Espectrometría de Masas en Tándem , Células Tumorales Cultivadas , Rayos UltravioletaRESUMEN
BACKGROUND: We sought to investigate the associations between pretreatment serum Carcinoembryonic antigen (CEA) level, 18F-Fluoro-2-deoxyglucose (18F-FDG) uptake value of primary tumor and epidermal growth factor receptor (EGFR) mutation status in non-small cell lung cancer (NSCLC). METHODS: We retrospectively reviewed medical records of 210 NSCLC patients who underwent EGFR mutation test and 18F-FDG positron emission tomography/computed tomography (PET/CT) scan before anti-tumor therapy. The associations between EGFR mutations and patients' characteristics, serum CEA, PET/CT imaging characteristics maximal standard uptake value (SUVmax) of the primary tumor were analyzed. Receiver-operating characteristic (ROC) curve was used to assess the predictive value of these factors. RESULTS: EGFR mutations were found in 70 patients (33.3%). EGFR mutations were more common in high CEA group (CEA ≥7.0 ng/mL) than in low CEA group (CEA <7.0 ng/mL) (40.4% vs. 27.6%; P=0.05). Females (P<0.001), non-smokers (P<0.001), patients with adenocarcinoma (P<0.001) and SUVmax <9.0 (P=0.001) were more likely to be EGFR mutation-positive. Multivariate analysis revealed that gender, tumor histology, pretreatment serum CEA level, and SUVmax were the most significant predictors for EGFR mutations. The ROC curve revealed that combining these four factors yielded a higher calculated AUC (0.80). CONCLUSIONS: Gender, histology, pretreatment serum CEA level and SUVmax are significant predictors for EGFR mutations in NSCLC. Combining these factors in predicting EGFR mutations has a moderate diagnostic accuracy, and is helpful in guiding anti-tumor treatment.
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BACKGROUND: Acinetobacter baumannii (A. baumannii), as a common opportunistic pathogen, has strong ability to form biofilms, which has led to drug resistance and chronic infections. The combination of N-acetylcysteine (NAC) and tigecycline (TGC) was demonstrated to synergistically inhibit biofilm-associated bacterial infections, including methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. The purpose of this study is to investigate the effect of NAC and TGC on planktonic cells and biofilms of A. baumannii. METHODS: Minimum inhibitory concentrations (MICs) of NAC were determined by broth microdilution method. Biofilm susceptibility was assessed by crystal violet stain. Interactive effects of NAC and TGC on planktonic cells were determined by checkerboard MIC assay. Viable cell count was used to evaluate the combined effect of NAC and TGC on biofilm-embedded bacteria. RESULTS: MICs of NAC against 25 A. baumannii isolates ranged from 16 to 128 mg/mL. NAC alone (0.5-128 mg/mL) significantly inhibited biofilm formation and disrupted preformed biofilms. The combination of NAC and TGC induced a partial synergistic effect (60%) and additive effect (28%) on planktonic bacteria. For biofilm-embedded bacteria, treatment with 16 mg/mL NAC alone or 2 µg/mL TGC alone resulted in significant bactericidal effects (P<0.01 and P<0.05, respectively); synergistic bactericidal effect was found at 4 mg/mL NAC combined with 0.5 µg/mL TGC (P<0.01). CONCLUSIONS: NAC alone significantly inhibited biofilm formation of A. baumannii. The combination of NAC and TGC induced partial synergistic effect against planktonic cells and synergistic effect against biofilm-embedded A. baumannii, which might be a therapeutic option for biofilm-related infections of A. baumannii.
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Polymers of intrinsic microporosity (PIMs) are porous polymers with rigid ladder-type chain structures. Synthesizing these polymers usually involves the step polymerization of two types of monomer, namely, active fluorine-substituted aromatic ring monomers and phenolic monomers. Herein, we report a new PIMs preparation method using self-synthesized fluorinated monomers and common monomer 5,5',6,6'-tetrahydroxy-3,3,3',3'-tetramethyl spirobisindane. The fluorinated monomers were synthesized through the imidization of tetrafluorophthalic anhydride and aromatic diamines. The resulting PIMs served as a support for palladium, with the formed catalyst showing potential for application in the Suzuki-Miyaura coupling reaction.
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INTRODUCTION: Various studies examined the relationship between the expression of phosphatase and tensin homolog (PTEN) with the clinical outcome in patients with lung cancer, but yielded conflicting results. EVIDENCE ACQUISITION: Electronic databases updated to January 2016 were searched to find relevant studies. A meta-analysis was conducted with eligible studies which quantitatively evaluated the relationship between the expression of PTEN and clinical outcomes of patients with lung cancer. Subgroup and sensitivity analysis were conducted. EVIDENCE SYNTHESIS: A total of 13 studies were included. When compared with high PTEN expression group, the lung cancer patients with reduced PTEN expression exhibited shorter overall survival (hazard ratio=0.40, 95%CI=0.32~0.52, P<0.001) and shorter progression-free survival (hazard ratio=0.53, 95%CI=0.38~0.74, P<0.001). In subgroup analysis, among lung cancer patients whose treatments including EGFR TKIs, we observed significant benefits of OS in high PTEN expression group. CONCLUSIONS: Reduced PTEN expression may be an indicator for poor prognosis in patients with lung cancer. It could have the same influence for patients whose treatments include EGFR-TKIs. The presence of PTEN expression may define a subset of patients with lung cancer appropriate for investigational therapeutic strategies.
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Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Fosfohidrolasa PTEN/genética , Supervivencia sin Enfermedad , Humanos , Pronóstico , Tasa de SupervivenciaRESUMEN
A number of studies have examined the association between tumor protein 53 (TP53) mutations and the clinical outcome in patients with non-small-cell lung cancer (NSCLC), although these have yielded conflicting results. In the present study, electronic databases updated to September 2015 were searched to find relevant studies. A meta-analysis was performed on the eligible studies, which quantitatively evaluated the association between the TP53 mutations and the survival of patients with NSCLC. Subgroup and sensitivity analyses were performed. A total of 19 studies that involved a total of 6,084 patients with NSCLC were included. When the TP53 mutation group (n=1,406) was compared with the wild-type group (lacking TP53 mutations; n=1,965), the wild-type group was associated with a significantly higher overall survival rate [hazard ratio (HR), 1.26; 95% confidence interval (CI) 1.12-1.41, P<0.0001]. Significant benefits of overall survival in the wild-type group were found in the subgroup involving patients with NSCLC in the early stages, including the I/II phases (HR, 1.93, 95% CI, 1.17-3.19, P=0.01; heterogeneity, I2=0.0%, P=0.976) and patients with adenocarcinoma (HR, 3.06; 95% CI, 1.66-5.62, P<0.0001; heterogeneity: I2=0.0%, P=0.976). This meta-analysis has indicated that TP53 gene alteration may be an indicator of a poor prognosis in patients with NSCLC. Furthermore, the results also suggested that the role of TP53 mutations may differ according to different pathological types and clinical stages. The presence of these mutations may define a subset of patients with NSCLC appropriate for investigational therapeutic strategies.