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1.
Int J Mol Sci ; 25(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38673957

RESUMO

Cuproptosis and ferroptosis represent copper- and iron-dependent forms of cell death, respectively, and both are known to play pivotal roles in head and neck squamous cell carcinoma (HNSCC). However, few studies have explored the prognostic signatures related to cuproptosis and ferroptosis in HNSCC. Our objective was to construct a prognostic model based on genes associated with cuproptosis and ferroptosis. We randomly assigned 502 HSNCC samples from The Cancer Genome Atlas (TCGA) into training and testing sets. Pearson correlation analysis was utilized to identify cuproptosis-associated ferroptosis genes in the training set. Cox proportional hazards (COX) regression and least absolute shrinkage operator (LASSO) were employed to construct the prognostic model. The performance of the prognostic model was internally validated using single-factor COX regression, multifactor COX regression, Kaplan-Meier analysis, principal component analysis (PCA), and receiver operating curve (ROC) analysis. Additionally, we obtained 97 samples from the Gene Expression Omnibus (GEO) database for external validation. The constructed model, based on 12 cuproptosis-associated ferroptosis genes, proved to be an independent predictor of HNSCC prognosis. Among these genes, the increased expression of aurora kinase A (AURKA) has been implicated in various cancers. To further investigate, we employed small interfering RNAs (siRNAs) to knock down AURKA expression and conducted functional experiments. The results demonstrated that AURKA knockdown significantly inhibited the proliferation and migration of HNSCC cells (Cal27 and CNE2). Therefore, AURKA may serve as a potential biomarker in HNSCC.


Assuntos
Aurora Quinase A , Biomarcadores Tumorais , Ferroptose , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Ferroptose/genética , Aurora Quinase A/metabolismo , Aurora Quinase A/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Prognóstico , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Masculino , Feminino , Estimativa de Kaplan-Meier , Proliferação de Células/genética
2.
Int J Mol Sci ; 24(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38139458

RESUMO

Disulfidptosis is a novel cell death mode in which the accumulation of disulfide bonds in tumor cells leads to cell disintegration and death. Long-stranded noncoding RNAs (LncRNAs) are aberrantly expressed in hepatocellular carcinoma (HCC) and have been reported to carry significant potential as a biomarker for HCC prognosis. However, lncRNA studies with disulfidptosis in hepatocellular carcinoma have rarely been reported. Therefore, this study aimed to construct a risk prognostic model based on the disulfidptosis-related lncRNA and investigate the mechanisms associated with disulfidptosis in hepatocellular carcinoma. The clinical and transcriptional information of 424 HCC patients was downloaded from The Cancer Genome Atlas (TCGA) and divided into test and validation sets. Furthermore, 1668 lncRNAs associated with disulfidptosis were identified using Pearson correlation. Six lncRNA constructs were finally identified for the risk prognostic model using one-way Cox proportional hazards (COX), multifactorial COX, and lasso regression. Kaplan-Meier (KM) analysis, principal component analysis, receiver operating characteristic curve (ROC), C-index, and column-line plot results confirmed that the constructed model was an independent prognostic factor. Based on the disulfidptosis risk score, risk groups were identified as potential predictors of immune cell infiltration, drug sensitivity, and immunotherapy responsiveness. Finally, we confirmed that phospholipase B domain containing 1 antisense RNA 1 (PLBD1-AS1) and muskelin 1 antisense RNA (MKLN1-AS) were highly expressed in hepatocellular carcinoma and might be potential biomarkers in HCC by KM analysis and quantitative real-time PCR (RT-qPCR). This study demonstrated that lncRNA related to disulfidptosis could serve as a biomarker to predict prognosis and treatment targets for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/genética , RNA Longo não Codificante/genética , Neoplasias Hepáticas/genética , Biomarcadores , RNA Antissenso
3.
Int J Mol Sci ; 24(12)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37373132

RESUMO

Cuproptosis is an unusual form of cell death caused by copper accumulation in mitochondria. Cuproptosis is associated with hepatocellular carcinoma (HCC). Long noncoding RNAs (LncRNAs) have been shown to be effective prognostic biomarkers, yet the link between lncRNAs and cuproptosis remains unclear. We aimed to build a prognostic model of lncRNA risk and explore potential biomarkers of cuproptosis in HCC. Pearson correlations were used to derive lncRNAs co-expressed in cuproptosis. The model was constructed using Cox, Lasso, and multivariate Cox regressions. Kaplan-Meier survival analysis, principal components analysis, receiver operating characteristic curve, and nomogram analyses were carried out for validation. Seven lncRNAs were identified as prognostic factors. A risk model was an independent prognostic predictor. Among these seven lncRNAs, prostate cancer associated transcript 6 (PCAT6) is highly expressed in different types of cancer, activating Wnt, PI3K/Akt/mTOR, and other pathways; therefore, we performed further functional validation of PCAT6 in HCC. Reverse transcription-polymerase chain reaction results showed that PCAT6 was aberrantly highly expressed in HCC cell lines (HepG2 and Hep3B) compared to LO2 (normal hepatocytes). When its expression was knocked down, cells proliferated and migrated less. PCAT6 might be a potential biomarker for predicting prognosis in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Masculino , Humanos , Carcinoma Hepatocelular/genética , Prognóstico , RNA Longo não Codificante/genética , Fosfatidilinositol 3-Quinases , Neoplasias Hepáticas/genética , Cobre , Apoptose/genética
4.
Ann Palliat Med ; 10(4): 4428-4434, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33966393

RESUMO

BACKGROUND: Sexual dysfunction is common in postoperative breast cancer patients, which seriously affects the quality of life of the patients, especially young patients. The aim of the present study was to investigate the incidence and risk factors of sexual dysfunction in young breast cancer survivors, so as to provide evidence for further intervention. METHODS: A total of 201 young breast cancer patients who were hospitalized in our department from October 2017 to October 2018 were retrospectively enrolled. The general information questionnaire and the female sexual function index (FSFI) questionnaire were used to evaluate the patients. RESULTS: Of these patients, 83.08% (167/201) of young breast cancer patients had sexual dysfunction. Total mastectomy (OR value single factor =7.843, OR value multiple factor =6.815), chemotherapy (OR value single factor =11.876, OR value multiple factor =38.711), and endocrine therapy (OR value single factor =19.688, OR value multiple factor =46.251) were independent risk factors of sexual dysfunction in young breast cancer survivors (P<0.05). CONCLUSIONS: Our study suggests that the incidence of sexual dysfunction in young breast cancer survivors is at a high level. Increasing the rate of breast conserving surgery and targeted intervention in patients with risk factors may help to reduce the incidence of sexual dysfunction and improve the quality of life in young breast cancer survivors.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Feminino , Humanos , Incidência , Mastectomia , Qualidade de Vida , Estudos Retrospectivos , Fatores de Risco , Inquéritos e Questionários
5.
Nat Commun ; 11(1): 4433, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895388

RESUMO

Surface lattice reconstruction is commonly observed in nickel-rich layered oxide battery cathode materials, causing unsatisfactory high-voltage cycling performance. However, the interplay of the surface chemistry and the bulk microstructure remains largely unexplored due to the intrinsic structural complexity and the lack of integrated diagnostic tools for a thorough investigation at complementary length scales. Herein, by combining nano-resolution X-ray probes in both soft and hard X-ray regimes, we demonstrate correlative surface chemical mapping and bulk microstructure imaging over a single charged LiNi0.8Mn0.1Co0.1O2 (NMC811) secondary particle. We reveal that the sub-particle regions with more micro cracks are associated with more severe surface degradation. A mechanism of mutual modulation between the surface chemistry and the bulk microstructure is formulated based on our experimental observations and finite element modeling. Such a surface-to-bulk reaction coupling effect is fundamentally important for the design of the next generation battery cathode materials.

6.
Biomaterials ; 230: 119635, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31767443

RESUMO

Oxygen deficiency is the main obstacle of hypoxia-related theranostics, thus this is a considerable amount of research focusing on the development of methods to supply oxygen by taking advantage of hypoxia-responsive properties of nanoparticles. However, strategies to properly penetrate hypoxic regions by the nanoparticles remains an unmet challenge. In this work, a biomimetic nanozyme capable of possessing catalase-like activity and the efficient direct penetration of hypoxic areas in tumor tissues was developed to supply oxygen based on catalytic tumor microenvironment-responsive reaction, providing substantial tumor hypoxia relief with nearly 3-fold reduction compared to untreated tumor tissues. To demonstrate the advantages of the nanozymes in overcoming hypoxia, a theranostic nanosystem model composed of the core/shell nanozymes and aggregation-induced emission (AIE) molecules was designed. The nanosystem was able to present multi-modal imaging of tumors and modulated the tumor microenvironment for improved photodynamic therapy (PDT) by cascade reactions of therapeutic effector molecules, thereby providing significantly enhanced therapeutic benefits in inhibiting tumor growth and lung metastasis of orthotopic breast cancer. This conceptual study showed the multifaceted features of biomimetic nanozymes as tumor therapeutics and demonstrated the encouraging potential for modulating hypoxia as an application for tumor theranostics.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Hipóxia , Neoplasias/tratamento farmacológico , Oxigênio/uso terapêutico , Medicina de Precisão , Microambiente Tumoral
7.
ACS Nano ; 12(5): 4946-4958, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29689158

RESUMO

Nanoparticle-based radio-sensitizers can amplify the effects of radiation therapy on tumor tissue even at relatively low concentrations while reducing the potential side effects to healthy surrounding tissues. In this study, we investigated a hybrid anisotropic nanostructure, composed of gold (Au) and titanium dioxide (TiO2), as a radio-sensitizer for radiation therapy of triple-negative breast cancer (TNBC). In contrast to other gold-based radio sensitizers, dumbbell-like Au-TiO2 nanoparticles (DATs) show a synergistic therapeutic effect on radiation therapy, mainly because of strong asymmetric electric coupling between the high atomic number metals and dielectric oxides at their interfaces. The generation of secondary electrons and reactive oxygen species (ROS) from DATs triggered by X-ray irradiation can significantly enhance the radiation effect. After endocytosed by cancer cells, DATs can generate a large amount of ROS under X-ray irradiation, eventually inducing cancer cell apoptosis. Significant tumor growth suppression and overall improvement in survival rate in a TNBC tumor model have been successfully demonstrated under DAT uptake for a radio-sensitized radiation therapy.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Radiossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo , Titânio/química , Neoplasias de Mama Triplo Negativas/radioterapia , Animais , Apoptose , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Humanos , Camundongos Nus , Transplante de Neoplasias , Polietilenoglicóis/química , Radiossensibilizantes/uso terapêutico , Distribuição Tecidual , Neoplasias de Mama Triplo Negativas/metabolismo
8.
Nat Commun ; 8: 14309, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28145406

RESUMO

Understanding the reaction pathway and kinetics of solid-state phase transformation is critical in designing advanced electrode materials with better performance and stability. Despite the first-order phase transition with a large lattice mismatch between the involved phases, spinel LiMn1.5Ni0.5O4 is capable of fast rate even at large particle size, presenting an enigma yet to be understood. The present study uses advanced two-dimensional and three-dimensional nano-tomography on a series of well-formed LixMn1.5Ni0.5O4 (0≤x≤1) crystals to visualize the mesoscale phase distribution, as a function of Li content at the sub-particle level. Inhomogeneity along with the coexistence of Li-rich and Li-poor phases are broadly observed on partially delithiated crystals, providing direct evidence for a concurrent nucleation and growth process instead of a shrinking-core or a particle-by-particle process. Superior kinetics of (100) facets at the vertices of truncated octahedral particles promote preferential delithiation, whereas the observation of strain-induced cracking suggests mechanical degradation in the material.

9.
J Chromatogr A ; 1420: 119-28, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26460073

RESUMO

To-date, there has been no effective chiral capillary electrophoresis-mass spectrometry (CE-MS) method reported for the simultaneous enantioseparation of the antidepressant drug, venlafaxine (VX) and its structurally-similar major metabolite, O-desmethylvenlafaxine (O-DVX). This is mainly due to the difficulty of identifying MS compatible chiral selector, which could provide both high enantioselectivity and sensitive MS detection. In this work, poly-sodium N-undecenoyl-L,L-leucylalaninate (poly-L,L-SULA) was employed as a chiral selector after screening several dipeptide polymeric chiral surfactants. Baseline separation of both O-DVX and VX enantiomers was achieved in 15 min after optimizing the buffer pH, poly-L,L-SULA concentration, nebulizer pressure and separation voltage. Calibration curves in spiked plasma (recoveries higher than 80%) were linear over the concentration range 150-5000 ng/mL for both VX and O-DVX. The limit of detection (LOD) was found to be as low as 30 ng/mL and 21 ng/mL for O-DVX and VX, respectively. This method was successfully applied to measure the plasma concentrations of human volunteers receiving VX or O-DVX orally when co-administered without and with indinivar therapy. The results suggest that micellar electrokinetic chromatography electrospray ionization-tandem mass spectrometry (MEKC-ESI-MS/MS) is an effective low cost alternative technique for the pharmacokinetics and pharmacodynamics studies of both O-DVX and VX enantiomers. The technique has potential to identify drug-drug interaction involving VX and O-DVX enantiomers while administering indinivar therapy.


Assuntos
Cromatografia Capilar Eletrocinética Micelar/métodos , Succinato de Desvenlafaxina/isolamento & purificação , Infecções por HIV/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Cloridrato de Venlafaxina/isolamento & purificação , Calibragem , Succinato de Desvenlafaxina/sangue , Interações Medicamentosas , Eletroforese Capilar/métodos , HIV/fisiologia , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Humanos , Indinavir/uso terapêutico , Limite de Detecção , Polímeros/química , Estereoisomerismo , Cloridrato de Venlafaxina/sangue
10.
Chemphyschem ; 14(3): 496-9, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23292881

RESUMO

Which side are you on? Scanning transmission X-ray microscopy is used for the first time to elucidate the coordination and distribution of aluminum in industrial-relevant zeolites at the single-particle level. Extended regions of a few hundred nanometers, rich in higher aluminum coordination environments, are heterogeneously embedded within the zeolite particle, before and after a steaming post-treatment.

11.
Environ Sci Technol ; 43(19): 7397-402, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19848152

RESUMO

San Francisco Bay has been contaminated historically by mercury from mine tailings as well as contemporary industrial sources. Native Spartina foliosa and non-native S. alterniflora-hybrid cordgrasses are dominant florae within the SF Bay estuary environment. Understanding mercury uptake and transformations in these plants will help to characterize the significance of their roles in mercury biogeochemical cycling in the estuarine environment. Methylated mercury can be biomagnified up the food web, resulting in levels in sport fish up to 1 million times greater than in surrounding waters and resulting in advisories to limit fish intake. Understanding the uptake and methylation of mercury in the plant rhizosphere can yield insight into ways to manage mercury contamination. The transmission X-ray microscope on beamline 6-2 at the Stanford Synchrotron Radiation Lightsource (SSRL) was used to obtain absorption contrast images and 3D tomography of Spartina foliosa roots that were exposed to 1 ppm Hg (as HgCl2) hydroponically for 1 week. Absorption contrast images of micrometer-sized roots from S. foliosa revealed dark particles, and dark channels within the root, due to Hg absorption. 3D tomography showed that the particles are on the root surface, and slices from the tomographic reconstruction revealed that the particles are hollow, consistent with microorganisms with a thin layer of Hg on the surface. Hg L3 XANES of ground-up plant roots and Hg L3 micro-XANES from microprobe analysis of micrometer-sized roots (60-120 microm in size) revealed three main types of speciation in both Spartina species: Hg-S ligation in a form similar to Hg(II) cysteine, Hg-S bonding as in cinnabar and metacinnabar, and methylmercury-carboxyl bonding in a form similar to methylmercury acetate. These results are interpreted within the context of obtaining a "snapshot" of mercury methylation in progress.


Assuntos
Espectrometria de Massas/métodos , Mercúrio/metabolismo , Microscopia/métodos , Raízes de Plantas/metabolismo , Poaceae/metabolismo , Mercúrio/química , Raízes de Plantas/química , São Francisco , Microbiologia do Solo
12.
Genes Dev ; 23(12): 1387-92, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19528316

RESUMO

Eukaryotic lanthionine synthetase C-like protein 1 (LanCL1) is homologous to prokaryotic lanthionine cyclases, yet its biochemical functions remain elusive. We report the crystal structures of human LanCL1, both free of and complexed with glutathione, revealing glutathione binding to a zinc ion at the putative active site formed by conserved GxxG motifs. We also demonstrate by in vitro affinity analysis that LanCL1 binds specifically to the SH3 domain of a signaling protein, Eps8. Importantly, expression of LanCL1 mutants defective in Eps8 interaction inhibits nerve growth factor (NGF)-induced neurite outgrowth, providing evidence for the biological significance of this novel interaction in cellular signaling and differentiation.


Assuntos
Glutationa/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Escherichia coli/genética , Regulação da Expressão Gênica , Humanos , Modelos Moleculares , Mutação , Fator de Crescimento Neural/farmacologia , Neuritos/fisiologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Células PC12 , Ligação Proteica , Estrutura Terciária de Proteína , Ratos , Receptores Acoplados a Proteínas G/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Zinco/metabolismo
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