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1.
Phys Chem Chem Phys ; 26(12): 9628-9635, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38466239

RESUMO

Valley is used as a new degree of freedom for information encoding and storage. In this work, the valley and topological properties of the VSiGeP4 monolayer were studied by adjusting the U value based on first-principles calculations. The VSiGeP4 monolayer remains in a ferromagnetic ground state regardless of the change in the U value. The magnetic anisotropy of the VSiGeP4 monolayer is initially in-plane, and then turns out-of-plane with the increase in the U value. Moreover, a topological phase transition is observed in the present VSiGeP4 monolayer with the increase in U value from 0 to 3 eV, i.e., the VSiGeP4 monolayer behaves as a bipolar magnetic semiconductor, a ferrovalley semiconductor, a half-valley metal characteristic, and a quantum anomalous Hall state. The mechanism of the topological phase transition behavior of the VSiGeP4 monolayer was analyzed. It was found that the variation in U values would change the strength of the electronic correlation effect, resulting in the valley and topological properties. In addition, carrier doping was studied to design a valleytronic device using this VSiGeP4 monolayer. By doping 0.05 electrons per f.u., the VSiGeP4 monolayer with a U value of 3 eV exhibits 100% spin polarization. This study indicates that the VSiGeP4 monolayer has potential applications in spintronic, valleytronic, and topological electronic nanodevices.

2.
Nano Lett ; 23(13): 6226-6232, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37363831

RESUMO

It has long been expected that the coexistence of ferroelectric and ferrovalley polarizations in one magnetic semiconductor could offer the possibility to revolutionize electronic devices. In this study, monolayer and bilayer YI2 are studied. Monolayer YI2 is a ferromagnetic semiconductor and exhibits a valley polarization up to 105 meV. All of the present bilayer YI2 regardless of stacking orders show antiferromagnetic states. Interestingly, the bilayer YI2 with 3R-type stackings shows not only valley polarization but also unexpected ferroelectric polarization, proving the concurrent ferrovalley and multiferroics behaviors. Moreover, the valley polarization of 3R-type bilayer YI2 can be reversed by controlling the direction of ferroelectric polarization through an electric field or manipulating the magnetization direction using an external magnetic field. The amazing phenomenon is also demonstrated in 2D van der Waals LaI2 and GdBr2 bilayers. A design idea of multifunctional devices is proposed based on the concurrent ferrovalley and multiferroics characteristics.

3.
Ecotoxicol Environ Saf ; 243: 113981, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36029576

RESUMO

Statins are prescribed widely as lipid-lowering agents. However, statins are associated with an increased harmful risk on public health and the ecosystem. Little is known about statins' toxicity on biological development and the underlying molecular mechanisms. We exposed zebrafish embryos to a series of statins to evaluate their development toxicity. Statins-induced embryonic developmental defects in a concentration-dependent manner. 72 h LC50 values for lovastatin, simvastatin, fluvastatin, atorvastatin, rosuvastatin, and pravastatin were 0.01 µM, 0.04 µM, 1.93 µM, 37.28 µM, 79.29 µM, and 2170 µM, respectively. Moreover, the expression of genes involved in heart contraction, calcium ion binding, transcription factors, nucleus, and G protein-coupled receptor signaling pathway was altered by statins. The early growth response gene (egr4) and transcription factor genes (fosab and fosb) were screened as potential toxicity targets due to their significant upregulation based on protein-protein interaction (PPI) and drug-gene interaction network analysis. Finally, the ecotoxicity profile of statins was predicted by in silico method, and statins were high or moderate risk to aquatic organisms. We provide a systems toxicology strategy to explore the toxicity of statins and illustrate the potential mechanisms of action.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Animais , Ecossistema , Ácidos Graxos Monoinsaturados , Inibidores de Hidroximetilglutaril-CoA Redutases/toxicidade , Indóis , Sinvastatina , Transcriptoma , Peixe-Zebra/genética
4.
Phys Chem Chem Phys ; 23(38): 21757-21768, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34550133

RESUMO

In this study, yttrium-doped CH3NH3PbI3 (Y-MAPbI3) and pure CH3NH3PbI3 (MAPbI3) perovskite films have been fabricated using a one-step solution spin coating method in a glove box. X-ray diffractometry and field-emission scanning electron microscopy were used to characterize the crystal structures and morphologies of perovskite films, respectively. It was found that the orientation of the crystal changed and the grains became more uniform in Y-MAPbI3 film, compared with the pure MAPbI3 perovskite film. The films were used to prepare the resistive switching memory devices with the device structure of Al/Y-MAPbI3 (MAPbI3)/ITO-glass. The memory performance of both devices was studied and showed a bipolar resistive switching behavior. The Al/MAPbI3/ITO device had an endurance of about 328 cycles. In contrast, the Al/Y-MAPbI3/ITO device exhibited an enhanced performance with a long endurance up to 3000 cycles. Moreover, the Al/Y-MAPbI3/ITO device also showed a higher ON/OFF ratio of over 103, long retention time (≥104 s), lower operation voltage (±0.5 V) and outstanding reproducibility. Additionally, the conduction mechanism of the high resistance state transformed from space-charge limited current for a Y free device to the Schottky emission after Y doping. The present results indicate that the Al/Y-MAPbI3/ITO device has a great potential to be used in high-performance memory devices.

5.
Mol Ther ; 28(5): 1299-1313, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32209435

RESUMO

Recently, cytoophidium, a nonmembrane-bound intracellular polymeric structure, has been shown to exist in various organisms, including tumor tissues, but its function and mechanism have not yet been examined. Examination of cytoophidia-assembled gene inosine monophosphate dehydrogenase (IMPDH) and cytidine triphosphate synthetase (CTPS) mRNA levels showed that only IMPDH1 levels were significantly higher in the clear cell renal cell carcinoma (ccRCC). IMPDH1 was positively correlated with the metastasis-related gene Y-box binding protein 1 (YB-1) and served as an independent prognostic factor in ccRCC. Kaplan-Meier analysis indicated that patients with tumors that expressed high IMPDH1 levels had a shorter overall survival (OS) and disease-free survival (DFS). Furthermore, detection of cytoophidia by immunofluorescence staining in ccRCC tissues showed that IMPDH1-assembled cytoophidia are positively associated with tumor metastasis. Mechanistically, IMPDH1 and YB-1 formed an autoregulatory positive feedback loop: IMPDH1 maintained YB-1 protein stabilization; YB-1 induced IMPDH1 expression by binding to the IMPDH1 promoter motif. Functionally, IMPDH1-assembled cytoophidia physically interacted with YB-1 and translocated YB-1 into the cell nucleus, thus correlating with ccRCC metastasis. Our findings provide the first solid theoretical rationale for targeting the IMPDH1/YB-1 axis to improve metastatic renal cancer treatment.


Assuntos
Carcinoma de Células Renais/metabolismo , Retroalimentação Fisiológica , IMP Desidrogenase/metabolismo , Neoplasias Renais/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Proteína 1 de Ligação a Y-Box/metabolismo , Animais , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , IMP Desidrogenase/genética , Estimativa de Kaplan-Meier , Neoplasias Renais/patologia , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Plasmídeos/genética , RNA Mensageiro/metabolismo , Transfecção , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína 1 de Ligação a Y-Box/genética
6.
Phys Chem Chem Phys ; 22(20): 11663-11670, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32406461

RESUMO

Spin-orbit coupling (SOC) has long been regarded as the core interaction to determine the efficiency of spin conserved transport in semiconductor spintronics. In this report, a spin-valve device with a Co/metal-free phthalocyanine (H2Pc)/Co stacking structure is fabricated. The magnetoresistance effect was successfully obtained in the device. It is also found that the magnetoresistance response is relatively smaller than that of metallic phthalocyanines, clearly implying that SOC is not the key factor to affect the magnetoresistance in phthalocyanine spin-valves. The dominant mechanism that determines the spin transport efficiency in the present H2Pc devices was systemically explored by combining both experimental measurements and first-principles calculation analysis. It was noticed that both the crystalline structure and molecular orientation of the H2Pc layer could be modified by the contact under-layer materials, which changes the magnetization intensity of the ferromagnetic metallic electrode due to the strong interface hybridization of Co/H2Pc. Meanwhile, the theoretical calculations clearly demonstrated that the spin filter effect from the second H2Pc layer should be responsible for the decrease of the magnetoresistance response in the present spin-valves compared to those using metallic phthalocyanine layers. This investigation may trigger new insights into the role of SOC strength and interface hybridization in organic spintronics.

7.
Exp Cell Res ; 376(2): 181-191, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30731073

RESUMO

Renal cell carcinomas are a group of most common renal malignancies whose clinical intervention is complicated by the lack of early diagnosis and reliable prognosis biomarkers, insensitive radiotherapy and chemotherapy and expensive molecular-targeted drugs. Transcriptional coactivator TAZ has been implicated in the formation and development of various malignancies. However, the biological characteristics and function of TAZ in renal cell carcinoma are still unclear. We attempted to evaluate the potential of TAZ as a promising diagnostic and prognostic molecular marker for renal cell carcinoma. In our study, we confirmed that TAZ was frequently elevated in renal cancer tissues and cells, consistent with the results of the publicly available cancer database. Moreover, elevated TAZ expression was positively correlated with poor overall survival time, high Fuhrman grade and distant metastasis. Our receiver operating characteristic curves analysis showed that high TAZ expression could distinguish renal cancer patients from normal persons (p < 0.0001). Kaplan-Meier curves demonstrated that high TAZ expression predicted poor overall survival (p < 0.0001). Multivariate regression analysis indicated that TAZ expression could be an independent prognostic factor (p = 0.002) in patients with renal cancer. Finally, the functional roles of TAZ knockdown were examined in renal cancer cell lines and nude mice subcutaneous tumor models. In conclusion, our results suggest that TAZ may serve as a promising diagnostic and prognostic molecular marker for patients with renal cancer. Moreover, TAZ may represent a novel clinical therapeutic target.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Renais/diagnóstico , Transativadores/metabolismo , Animais , Apoptose , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Progressão da Doença , Feminino , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Renais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Estadiamento de Neoplasias , Transplante de Neoplasias , Prognóstico , Transativadores/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional
8.
J Pineal Res ; 67(4): e12607, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31469445

RESUMO

Metabolic adaptations are emerging hallmarks of cancer progression and cellular transformation. Clear cell renal cell carcinoma (ccRCC) is a metabolic disease defined histologically by lipid accumulation and lipid storage, which promote tumor cell survival; however, the significance of eliminating the lipid remains unclear. Here, we demonstrate that melatonin activates transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1A (PGC1A) and uncoupling protein 1 (UCP1)-dependent lipid autophagy and a lipid browning program to elicit a catabolic state called "tumor slimming," thus suppressing tumor progression. Metabolic coregulator data analysis revealed that PGC1A expression was decreased in ccRCC tissues versus normal tissues, and poor patient outcome was associated with lower expression of PGC1A in The Cancer Genome Atlas (TCGA-KIRC). PGC1A was downregulated in ccRCC and associated with disease progression. Restoration of PGC1A expression by melatonin in ccRCC cells significantly repressed tumor progression and eliminated the abnormal lipid deposits. Furthermore, a phenomenon called "tumor slimming" was observed, in which tumor cell volume was reduced and lipid droplets transformed into tiny pieces. Additional studies indicated that melatonin promoted "tumor slimming" and suppressed ccRCC progression through PGC1A/UCP1-mediated autophagy and lipid browning. During this process, autophagy and lipid browning eliminate lipid deposits without providing energy. These studies demonstrate that the novel "tumor slimming" pathway mediated by melatonin/PGC1A/UCP1 exhibits prognostic potential in ccRCC, thus revealing the significance of monitoring and manipulating this pathway for cancer therapy.


Assuntos
Morte Celular Autofágica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Melatonina/farmacologia , Proteínas de Neoplasias/metabolismo , Neoplasias , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteína Desacopladora 1/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Camundongos , Proteínas de Neoplasias/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Proteína Desacopladora 1/genética , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Phys Chem Chem Phys ; 21(5): 2443-2452, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30652708

RESUMO

The interfacial magnetic interaction and coupling mechanism for τ-MnAl with Fe(Co) atomic layers have been studied using first principles calculations. The stable surface and interface were firstly determined by the surface energy of τ-MnAl and interface energy of τ-MnAl/Fe(Co) films, respectively. Their magnetic coupling interactions were investigated by varying the Fe(Co) atomic layer numbers. It is noted that both Fe and Co exhibited ferromagnetic coupling with τ-MnAl. Interestingly, an unusual oscillation phenomenon of magnetic coupling for τ-MnAl with Fe(Co) atomic layers was observed depending on the layer thickness of Fe(Co). Moreover, Fe and Co showed different oscillation modes. The energy difference between antiferromagnetic and ferromagnetic states is larger for τ-MnAl/Fe and τ-MnAl/Co when the Fe(Co) layer numbers are even and odd, respectively. Their mechanisms were analyzed based on the band structures and the confinement of electrons in quantum wells. It is found that the magnetic coupling oscillation in τ-MnAl/Fe originated from both the spin up Δ1 band and spin down Δ5 band at the [capital Gamma, Greek, macron] points. Comparatively, the oscillation of τ-MnAl/Co is due to the spin up band at the X[combining macron] point. The present results could provide insight to further understand interfacial exchange interactions among magnetic layers.

10.
Exp Cell Res ; 358(2): 269-278, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28684115

RESUMO

Caveolin-1 (CAV1) has been identified to be up-regulated in many cancers, including clear cell renal cell carcinoma (ccRCC). However, its potential function is still unclear in ccRCC. In this study, we demonstrated that CAV1 was frequently overexpressed in renal cell carcinoma tissues and cells, and was significantly associated with various clinicopathological parameters. In addition, high CAV1 expression was associated with poor disease-free survival (DFS) rate and could serve as a useful diagnostic indicator in ccRCC patients with different clinicopathological stages. Functional experiments demonstrated that CAV1 knockdown inhibited cell migration and invasion, whereas overexpression of CAV1 promoted cell migration and invasion in ccRCC. Moreover, CAV1 expression was up-regulated in sunitinib-resistant renal cancer cell lines, and its overexpression promoted sunitinib resistance. In general, our results confirm that CAV1 plays an important role in the metastasis of kidney cancer and induces sunitinib resistance, so CAV1 function suppression may become a promising clinical treatment strategy during renal cell carcinoma metastasis and sunitinib resistance.


Assuntos
Carcinoma de Células Renais/metabolismo , Caveolina 1/metabolismo , Movimento Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/genética , Indóis/farmacologia , Neoplasias Renais/metabolismo , Pirróis/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Caveolina 1/genética , Proliferação de Células/genética , Proliferação de Células/fisiologia , Feminino , Técnicas de Silenciamento de Genes/métodos , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Sunitinibe , Adulto Jovem
11.
Cell Physiol Biochem ; 43(6): 2420-2433, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29073615

RESUMO

BACKGROUND/AIMS: We previously performed microRNA (miRNA) microarray to identify effective indicators of clear cell renal cell carcinoma (ccRCC) tissue samples and preoperative/postoperative plasma in which we identified miR-144-3p as an oncomiRNA. However, the molecular mechanism of miR-144-3p remains unclear. This study aims to explore the roles of miR-144-3p in the invasion, migration and Sunitinib-resistance in ccRCC and to elucidate the underlying mechanisms. METHODS: Gain and loss of function approaches were used to investigate the cell proliferation, cycle distribution, clonogenicity, migration, invasion, chemosensitivity of miR-144-3p in vitro. The xenograft model was used to assess the effects of miR-144-3p overexpression on tumorigenesis. Bioinformatics analysis and dual-luciferase reporter assay were used to indentify AT-rich interactive domain 1A (ARID1A) as a direct target gene of miR-144-3p. Quantitative RT-PCR, Western blotting, and immunohistochemical (IHC) staining were used to explore ARID1A expression level of the mRNA and protein. RESULTS: We found that miR-144-3p overexpression enhanced cell proliferation, clonogenicity, migration, invasion, and chemoresistance in ccRCC cells. Notably, the oncotumor activities of miR-144-3p were mediated by repressing the expression of ARID1A. The downregulation of ARIDIA could promote the function of miR-144-3p in cell proliferation, metastasis and chemoresistance. Consistently, ARID1A mRNA and protein levels were decreased in ccRCC and in nude mice, and they negatively correlated with miR-144-3p. CONCLUSION: Higher miR-144-3p may enhance malignancy and resistance to Sunitinib in ccRCC by targeting ARID1A, the observations may uncover novel strategies of ccRCC treatment.


Assuntos
Carcinoma de Células Renais/patologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Renais/patologia , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Regiões 3' não Traduzidas , Animais , Antagomirs/metabolismo , Sequência de Bases , Carcinogênese , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteínas de Ligação a DNA , Regulação para Baixo , Humanos , Indóis/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/metabolismo , Masculino , Camundongos , Camundongos Nus , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Mutagênese , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Pirróis/uso terapêutico , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Alinhamento de Sequência , Sunitinibe , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Transplante Heterólogo , Regulação para Cima
13.
Chem Res Toxicol ; 26(8): 1168-81, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-23848171

RESUMO

Cephalosporins, derivatives of 7-aminocephalosporanic acid (7-ACA), are potent antibacterial agents. The toxicity prediction of these compounds is of considerable importance in new drug development. Zebrafish embryo toxicity testing was thought to be suitable for evaluation of the toxic properties of cephalosporins. Here, five kinds of cephalosporins and their isomers were used for investigation of the toxic functional groups of cephalosporins and for further evaluation of the efficacy of zebrafish embryo toxicity testing. Computational chemistry methods were also used to study the conformations of the stereoisomers of cephalosporins in aqueous solution to explore the relationship between the stereoisomers and the experimental results of toxicity tests on zebrafish embryos. Our results suggest that both the C-7 and C-3 substituents of cephalosporins are toxic functional groups. The toxic functional groups increase the toxic reaction of 7-ACA and can induce variable abnormal phenotypes in zebrafish embryo toxicity testing. The embryonic toxicities of cephalosporins were involved in organogenesis, mainly in the development of the cranial nerve, cardiovascular system, notochord and abdomen, and pigment formation; those tissues and organs are derived from ectoderm, mesoderm, and endoderm. The theoretical calculations showed a strong negative correlation between topological polar surface area (TPSA) values and the toxic effect, which indicated that molecular polarity may be crucial to the toxic effects of the isomers of cephalosporins. The concept of toxic functional groups may help us understand the safety differences of cephalosporins.


Assuntos
Antibacterianos/toxicidade , Cefalosporinas/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Peixe-Zebra/crescimento & desenvolvimento , Animais , Antibacterianos/química , Sistema Cardiovascular/efeitos dos fármacos , Sistema Cardiovascular/crescimento & desenvolvimento , Cefalosporinas/química , Embrião não Mamífero/metabolismo , Modelos Teóricos , Sistema Nervoso/efeitos dos fármacos , Sistema Nervoso/crescimento & desenvolvimento , Notocorda/efeitos dos fármacos , Notocorda/crescimento & desenvolvimento , Fenótipo , Estereoisomerismo , Água/química
14.
Nanoscale ; 15(18): 8278-8288, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37078633

RESUMO

Two-dimensional ferrovalley materials should simultaneously possess three characteristics, that is, a Curie temperature beyond atmospheric temperature, perpendicular magnetic anisotropy, and large valley polarization for potential commercial applications. In this report, we predict two ferrovalley Janus RuClX (X = F, Br) monolayers by first-principles calculations and Monte Carlo simulations. The RuClF monolayer exhibited a valley-splitting energy as large as 194 meV, perpendicular magnetic anisotropy energy of 187 µeV per f.u., and Curie temperature of 320 K. Thus, spontaneous valley polarization at room temperature will be present in the RuClF monolayer, which is nonvolatile for spintronic and valleytronic devices. Although the valley-splitting energy of the RuClBr monolayer was as high as 226 meV with magnetic anisotropy energy of 1.852 meV per f.u., the magnetic anisotropy of the RuClBr monolayer was in-plane, and its Curie temperature was only 179 K. The orbital-resolved magnetic anisotropy energy revealed that the interaction between the occupied spin-up states of dyz and the unoccupied spin-down states of dz2 dominated the out-of-plane magnetic anisotropy in the RuClF monolayer, but the in-plane magnetic anisotropy of the RuClBr monolayer was mostly contributed by the coupling of the dxy and dx2-y2 orbitals. Interestingly, the valley polarizations in the Janus RuClF and RuClBr monolayers appeared in their valence band and conduction band, respectively. Thus, two anomalous valley Hall devices are proposed using the present Janus RuClF and RuClBr monolayers with hole and electron doping, respectively. This study provides interesting and alternative candidate materials for the development of valleytronic devices.

15.
Cancer Res ; 83(23): 3920-3939, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37729394

RESUMO

Fatty acid metabolism reprogramming is a prominent feature of clear cell renal cell carcinoma (ccRCC). Increased lipid storage supports ccRCC progression, highlighting the importance of understanding the molecular mechanisms driving altered fatty acid synthesis in tumors. Here, we identified that malonyl-CoA decarboxylase (MLYCD), a key regulator of fatty acid anabolism, was downregulated in ccRCC, and low expression correlated with poor prognosis in patients. Restoring MLYCD expression in ccRCC cells decreased the content of malonyl CoA, which blocked de novo fatty acid synthesis and promoted fatty acid translocation into mitochondria for oxidation. Inhibition of lipid droplet accumulation induced by MLYCD-mediated fatty acid oxidation disrupted endoplasmic reticulum and mitochondrial homeostasis, increased reactive oxygen species levels, and induced ferroptosis. Moreover, overexpressing MLYCD reduced tumor growth and reversed resistance to sunitinib in vitro and in vivo. Mechanistically, HIF2α inhibited MLYCD translation by upregulating expression of eIF4G3 microexons. Together, this study demonstrates that fatty acid catabolism mediated by MLYCD disrupts lipid homeostasis to repress ccRCC progression. Activating MLYCD-mediated fatty acid metabolism could be a promising therapeutic strategy for treating ccRCC. SIGNIFICANCE: MLYCD deficiency facilitates fatty acid synthesis and lipid droplet accumulation to drive progression of renal cell carcinoma, indicating inducing MYLCD as a potential approach to reprogram fatty acid metabolism in kidney cancer.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Metabolismo dos Lipídeos , Ácidos Graxos/metabolismo
16.
Yao Xue Xue Bao ; 47(2): 223-8, 2012 Feb.
Artigo em Zh | MEDLINE | ID: mdl-22512035

RESUMO

The paper reports the systematic study on felodipine and its impurities in tablets, to improve its quality standards for the control of the related substances. HPLC-DAD, UPLC-MS, IR and NMR methods were used for the isolation of felodipine and its impurities in tablets, their identification and the zebrafish animal model was used for the analysis of the toxic impurities. In felodipine material and its tablets, three impurities are isolated and identified. They are impurity 1 [dimethyl 4-(2, 3-dichlorophenyl)-2, 6-dimethyl-1, 4-dihydropyridine-3, 5-dicarboxylate], impurity 2 [ethyl methyl 4-(2, 3-dichlorophenyl)-2, 6-dimethylpyridine-3, 5-dicarboxylate] and impurity 3 [diethyl 4-(2, 3-dichlorophenyl)-2, 6-dimethyl-1, 4-dihydropyridine-3, 5-dicarboxylate], separately. The result of zebrafish animal model analysis showed that the teratogenic effects of four compounds were: impurity 3 > or = felodipine > impurity 1 > impurity 2, lethal effects were as follows: impurity 2 = impurity 3 > felodipine > or = impurity 1. This study confirmed the toxicity of three impurities in felodipine. According to the results, the paper suggested the amendments to the standard of the medicine and provided the support to the control of impurities in the manufacturing process.


Assuntos
Anti-Hipertensivos/química , Bloqueadores dos Canais de Cálcio/química , Contaminação de Medicamentos , Felodipino/química , Preparações Farmacêuticas/química , Anormalidades Induzidas por Medicamentos , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/toxicidade , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/toxicidade , Cromatografia Líquida de Alta Pressão/métodos , Felodipino/administração & dosagem , Felodipino/toxicidade , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Preparações Farmacêuticas/análise , Controle de Qualidade , Espectrofotometria Infravermelho , Comprimidos , Espectrometria de Massas em Tandem , Peixe-Zebra
17.
Yi Chuan ; 34(9): 1165-73, 2012 Sep.
Artigo em Zh | MEDLINE | ID: mdl-23017458

RESUMO

To further understand the neural toxicity and teratogenicity of antiepileptic drugs in clinic, we established a zebrafish model for antiepileptic toxicity using trimethadione as a probe drug. The results indicated that embryonic malformation occurred under trimethadione treatment in a concentration-dependent manner. The defects included growth retardation, small head, eyes and acoustic capsule, deficient semicircular canals and otolith, and abnormal cardiovascular system. The number of hair cells in neuromast ML2 was obviously reduced in the treated larvae. Whole mount in situ hybridization indicated that the gene expression patterns of brain marker genes, such as zic1 and xb51, and autophagic gene atg5 was changed significantly. The result of RT-PCR showed that the expressions of hearing genes val and hmx2 were also changed in the trimethadione-treated embryos. All these findings suggest that brain tissue and the neural sensors for body balance and hearing are the main targets of trimethadione toxicity, and that zebrafish is able to mimic mammal responses to the teratogenicity and the neural toxicity of trimethadione in the embryonic and larva development.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Teratogênicos/toxicidade , Trimetadiona/toxicidade , Peixe-Zebra/embriologia , Anormalidades Múltiplas/induzido quimicamente , Animais , Desenvolvimento Embrionário/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos
18.
Sci Adv ; 8(15): eabk0159, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427156

RESUMO

Supplying wireless power is a challenging technical problem of great importance for implantable biomedical devices. Here, we introduce a novel implantable piezoelectric ultrasound energy-harvesting device based on Sm-doped Pb(Mg1/3Nb2/3)O3-PbTiO3 (Sm-PMN-PT) single crystal. The output power density of this device can reach up to 1.1 W/cm2 in vitro, which is 18 times higher than the previous record (60 mW/cm2). After being implanted in the rat brain, under 1-MHz ultrasound with a safe intensity of 212 mW/cm2, the as-developed device can produce an instantaneous effective output power of 280 µW, which can immediately activate the periaqueductal gray brain area. The rat electrophysiological experiments under anesthesia and behavioral experiments demonstrate that our wireless-powered device is well qualified for deep brain stimulation and analgesia applications. These encouraging results provide new insights into the development of implantable devices in the future.

19.
Artigo em Inglês | MEDLINE | ID: mdl-36301911

RESUMO

Two-dimensional (2D) nanomaterials hold great potential for cancer theranostic applications, yet their clinical translation faces great challenges of high toxicity and limited therapeutic/diagnostic modality. Here, we have created a kind of symbiotic 2D carbon-2D clay nanohybrids, which are composed of a novel 2D carbon nanomaterial (carbon nanochips, or CNC), prepared by carbonizing a conjugated polymer polydiiodobutadiyne, and a 2D layered aluminosilicate clay mineral montmorillonite (MMT). Intriguingly, with the formation of the nanohybrids, MMT can help the dispersion of CNC, while CNC can significantly reduce the hemolysis and toxicity of MMT. The symbiotic combination of CNC and MMT also leads to a synergistic anti-cancer theranostic effect. CNC has a strong absorption and high photothermal conversion efficiency in the second near-infrared region (NIR-II, 1000-1700 nm), while MMT contains Fe3+ that can facilitate the generation of reactive oxygen species from highly expressed H2O2 in tumor microenvironment. The nanohybrids not only enable a synergy of photothermal therapy and chemodynamic therapy to suppress the extremely rapid growth of RM1 tumors in mice but also allow for dual photoacoustic and magnetic imaging to guide the drug delivery and NIR-II irradiation execution, hence establishing a highly efficient and biosafe "all-in-one" theranostic platform for precision nanomedicine.

20.
Front Genet ; 13: 648134, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281807

RESUMO

Renal cell carcinoma (RCC) is one of the most common malignancies in the urinary system. The mortality of advanced RCC remains high despite advances in systemic therapy of RCC. Considering the misdiagnosis of early-stage RCC, the identification of effective biomarkers is of great importance. Tissue inhibitor matrix metalloproteinase 1 (TIMP1), which belongs to TIMP gene family, is a natural inhibitor of the matrix metalloproteinases (MMPs). In this study, we found TIMP1 was significantly up-regulated in cell lines and RCC tissues. Kaplan-Meier analysis revealed that high expression of TIMP1 indicated a poor prognosis. Multivariate analysis further indicated that TIMP1 overexpression was an independent prognostic factor of RCC patients. Furthermore, knockdown of TIMP1 in vitro suppressed the proliferation, migration, and invasion of RCC cells, while upregulating TIMP1 accelerated the proliferation, migration, and invasion of RCC cells. In addition, we also found that TIMP1 prompted the progression of RCC via epithelial-to-mesenchymal transition (EMT) signaling pathway. In conclusion, the present results suggested that TIMP1 indicated poor prognosis of renal cell carcinoma and could serve as a potential diagnostic and prognostic biomarker for RCC.

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