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1.
PLoS One ; 19(6): e0297215, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38875297

RESUMO

Dianthus barbatus linn. is widely used in gardens, mainly as flower beds and flower borders. The effects of different gradients of P on the growth and root morphology of Dianthus barbatus were studied to explore its morphological and physiological responses and adaptive strategies. Hence, this study provides a theoretical basis and practical guidance for D. barbatus production. Two soil substrates, namely loess and vegetable soil, and five phosphorus concentration gradients were set; no phosphorus application was used as the control. The morphology and physiology of D. barbatus were also investigated. Low-to-medium- and low-phosphorus treatments promoted the growth of D. barbatus in the above and underground parts of the plants grown on both substrates. Chlorophyll content, flower quantity, and acid phosphatase activity in the rhizosphere soil were significantly increased in the H1 and H2 treatments of loess and in the C4 treatment of vegetable soil. Thus, D. barbatus seems to reduce the damage caused by phosphorus stress by increasing chlorophyll content and root acid phosphatase activity. The latter was significantly higher in vegetable soil than in loess. Vegetable soil was more conducive to D. barbatus growth than loess.


Assuntos
Clorofila , Dianthus , Fósforo , Raízes de Plantas , Solo , Fósforo/metabolismo , Solo/química , Clorofila/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Dianthus/crescimento & desenvolvimento , Dianthus/metabolismo , Dianthus/fisiologia , Fosfatase Ácida/metabolismo , Flores/metabolismo , Flores/crescimento & desenvolvimento , Rizosfera
2.
Nat Cancer ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519786

RESUMO

Cancers commonly reprogram translation and metabolism, but little is known about how these two features coordinate in cancer stem cells. Here we show that glioblastoma stem cells (GSCs) display elevated protein translation. To dissect underlying mechanisms, we performed a CRISPR screen and identified YRDC as the top essential transfer RNA (tRNA) modification enzyme in GSCs. YRDC catalyzes the formation of N6-threonylcarbamoyladenosine (t6A) on ANN-decoding tRNA species (A denotes adenosine, and N denotes any nucleotide). Targeting YRDC reduced t6A formation, suppressed global translation and inhibited tumor growth both in vitro and in vivo. Threonine is an essential substrate of YRDC. Threonine accumulated in GSCs, which facilitated t6A formation through YRDC and shifted the proteome to support mitosis-related genes with ANN codon bias. Dietary threonine restriction (TR) reduced tumor t6A formation, slowed xenograft growth and augmented anti-tumor efficacy of chemotherapy and anti-mitotic therapy, providing a molecular basis for a dietary intervention in cancer treatment.

3.
J Colloid Interface Sci ; 660: 617-627, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38266343

RESUMO

Clean H2 fuel obtained from the photocatalytic water splitting to hydrogen reaction could efficiently alleviate current energy crisis and the concomitant environmental pollution problems. Therefore, it is desirable to search for a highly efficient photocatalytic system to decrease the energy barrier of water splitting reaction. Herein, the 1T/2H mixed phase MoS2 sample with Schottky junction between contact interfaces is developed through molten salt synthesis for photocatalytic hydrogen production under a dye-sensitized system (Eosin Y-TEOA-MoS2) driven by the visible light. In mixed phase MoS2 sample, the photogenerated electrons of 2H-phase MoS2 migrated to the 1T-phase MoS2 are difficult to jump back because of the existence of Schottky barrier, which greatly suppresses the quenching of EY and therefore results in an enhanced hydrogen evolution performance. Therefore, the optimized MoS2 sample (MoS2-350) has an initial hydrogen evolution rate of 213 µmol h-1 and corresponding apparent quantum yield of 36.1 % at 420 nm, far higher than those of pure Eosin Y. It is strongly confirmed by the steady-state/time-resolved photoluminescence (PL) spectra and transient photocurrent response experiments. With the assistance of Density functional theory (DFT) calculation, the function of Schottky junction in photocatalytic hydrogen evolution reaction is well explained. In addition, a new and universal method (SVM curve) of judging oxidation or reduction quenching for photosensitizers is proposed.

4.
Sensors (Basel) ; 23(16)2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37631686

RESUMO

Power distribution and battery thermal management are important technologies for improving the energy efficiency of plug-in hybrid electric vehicles (PHEVs). In response to the global optimization of integrated energy thermal management strategy (IETMS) for PHEVs, a dynamic programming algorithm based on adaptive grid optimization (AGO-DP) is proposed in this paper to improve optimization performance by reducing the optimization range of SOC and battery temperature, and adaptively adjusting the grid distribution of state variables according to the actual feasible region. The simulation results indicate that through AGO-DP optimization, the reduction ratio of the state feasible region is more than 30% under different driving conditions. Meanwhile, the algorithm can obtain better global optimal driving costs more rapidly and accurately than traditional dynamic programming algorithms (DP). The computation time is reduced by 33.29-84.67%, and the accuracy of the global optimal solution is improved by 0.94-16.85% compared to DP. The optimal control of the engine and air conditioning system is also more efficient and reasonable. Furthermore, AGO-DP is applied to explore IETMS energy-saving potential for PHEVs. It is found that the IETMS energy-saving potential range is 3.68-23.74% under various driving conditions, which increases the energy-saving potential by 0.55-3.26% compared to just doing the energy management.

5.
Kaohsiung J Med Sci ; 39(10): 966-977, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37530654

RESUMO

The epithelial-mesenchymal transition (EMT) is closely associated with Crohn's disease (CD) related intestinal fibrosis, a condition whose prevalence is increasing annually among children. Recently, the CD marker gene microarray screening revealed an upregulation of circ_0001666 in the colon tissues of CD patients, but its underlying mechanisms remain unclear. In this study, we explored the molecular mechanism of circ_0001666 in regulating EMT-mediated fibrosis in CD in vitro. The levels of circ_0001666 and EMT-associated proteins were assessed in CD clinical samples, and a CD cell model was established using TGF-ß1 to induce human intestinal epithelial cells (HIECs). Additionally, the expression levels of genes and proteins related to EMT and fibrosis were analyzed by quantitative real-time PCR and western blot, cell migration, and invasion were assessed via wound healing assay and transwell, respectively, and RNA pull-down and RNA immunoprecipitation assays were performed to verify the relationship between SRSF1 and BMP7 or circ_0001666. Circ_0001666 was overexpressed in the intestinal mucosal tissues of CD patients and was positively correlated with EMT. Silencing circ_0001666 inhibited the migration, invasion, EMT, and fibrosis of HIECs induced by TGF-ß1. Mechanistically, circ_0001666 regulated BMP7 expression by interacting with SRSF1. Furthermore, the effects of inhibiting circ_0001666 on HIECs could be partially reversed by overexpressing SRSF1 or silencing BMP7. Collectively, circ_0001666 regulates TGF-ß1-induced HIEC migration, invasion, EMT, and fibrosis. Circ_0001666 also promoted EMT-mediated fibrosis by interacting with SRSF1 to accelerate BMP7 mRNA decay. These findings provide new insights into the pathogenesis of CD and suggest that circ_0001666 might be a potential therapeutic target for CD.

6.
Nature ; 617(7962): 818-826, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37198486

RESUMO

Cancer cells rewire metabolism to favour the generation of specialized metabolites that support tumour growth and reshape the tumour microenvironment1,2. Lysine functions as a biosynthetic molecule, energy source and antioxidant3-5, but little is known about its pathological role in cancer. Here we show that glioblastoma stem cells (GSCs) reprogram lysine catabolism through the upregulation of lysine transporter SLC7A2 and crotonyl-coenzyme A (crotonyl-CoA)-producing enzyme glutaryl-CoA dehydrogenase (GCDH) with downregulation of the crotonyl-CoA hydratase enoyl-CoA hydratase short chain 1 (ECHS1), leading to accumulation of intracellular crotonyl-CoA and histone H4 lysine crotonylation. A reduction in histone lysine crotonylation by either genetic manipulation or lysine restriction impaired tumour growth. In the nucleus, GCDH interacts with the crotonyltransferase CBP to promote histone lysine crotonylation. Loss of histone lysine crotonylation promotes immunogenic cytosolic double-stranded RNA (dsRNA) and dsDNA generation through enhanced H3K27ac, which stimulates the RNA sensor MDA5 and DNA sensor cyclic GMP-AMP synthase (cGAS) to boost type I interferon signalling, leading to compromised GSC tumorigenic potential and elevated CD8+ T cell infiltration. A lysine-restricted diet synergized with MYC inhibition or anti-PD-1 therapy to slow tumour growth. Collectively, GSCs co-opt lysine uptake and degradation to shunt the production of crotonyl-CoA, remodelling the chromatin landscape to evade interferon-induced intrinsic effects on GSC maintenance and extrinsic effects on immune response.


Assuntos
Histonas , Lisina , Neoplasias , Processamento de Proteína Pós-Traducional , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Glutaril-CoA Desidrogenase/metabolismo , Histonas/química , Histonas/metabolismo , Lisina/deficiência , Lisina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , RNA de Cadeia Dupla/imunologia , Humanos , Animais , Camundongos , Interferon Tipo I/imunologia
7.
Nat Neurosci ; 26(4): 542-554, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36941428

RESUMO

Reactive astrocytes play an important role in neurological diseases, but their molecular and functional phenotypes in epilepsy are unclear. Here, we show that in patients with temporal lobe epilepsy (TLE) and mouse models of epilepsy, excessive lipid accumulation in astrocytes leads to the formation of lipid-accumulated reactive astrocytes (LARAs), a new reactive astrocyte subtype characterized by elevated APOE expression. Genetic knockout of APOE inhibited LARA formation and seizure activities in epileptic mice. Single-nucleus RNA sequencing in TLE patients confirmed the existence of a LARA subpopulation with a distinct molecular signature. Functional studies in epilepsy mouse models and human brain slices showed that LARAs promote neuronal hyperactivity and disease progression. Targeting LARAs by intervention with lipid transport and metabolism could thus provide new therapeutic options for drug-resistant TLE.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Humanos , Camundongos , Animais , Astrócitos/metabolismo , Progressão da Doença , Modelos Animais de Doenças , Lipídeos , Apolipoproteínas E/metabolismo , Hipocampo/metabolismo
8.
JCI Insight ; 8(6)2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36795488

RESUMO

Glioblastoma is the most malignant primary brain tumor, the prognosis of which remains dismal even with aggressive surgical, medical, and radiation therapies. Glioblastoma stem cells (GSCs) promote therapeutic resistance and cellular heterogeneity due to their self-renewal properties and capacity for plasticity. To understand the molecular processes essential for maintaining GSCs, we performed an integrative analysis comparing active enhancer landscapes, transcriptional profiles, and functional genomics profiles of GSCs and non-neoplastic neural stem cells (NSCs). We identified sorting nexin 10 (SNX10), an endosomal protein sorting factor, as selectively expressed in GSCs compared with NSCs and essential for GSC survival. Targeting SNX10 impaired GSC viability and proliferation, induced apoptosis, and reduced self-renewal capacity. Mechanistically, GSCs utilized endosomal protein sorting to promote platelet-derived growth factor receptor ß (PDGFRß) proliferative and stem cell signaling pathways through posttranscriptional regulation of the PDGFR tyrosine kinase. Targeting SNX10 expression extended survival of orthotopic xenograft-bearing mice, and high SNX10 expression correlated with poor glioblastoma patient prognosis, suggesting its potential clinical importance. Thus, our study reveals an essential connection between endosomal protein sorting and oncogenic receptor tyrosine kinase signaling and suggests that targeting endosomal sorting may represent a promising therapeutic approach for glioblastoma treatment.


Assuntos
Glioblastoma , Humanos , Animais , Camundongos , Glioblastoma/tratamento farmacológico , Nexinas de Classificação/genética , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais , Proteínas Tirosina Quinases/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo
9.
Chem Asian J ; 17(16): e202200342, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35713953

RESUMO

Intravesical instillation of chemotherapeutic drugs such as epirubicin (EPI) is routinely used to prevent tumor recurrence and progression after transurethral resection of bladder tumor. However, the lack of tumor selectivity often causes severe damage to normal bladder urothelium leading to intolerable side effects. Here, we analyzed abnormal changes in glycosylation in bladder cancer and identified mannose as the most aberrantly expressed glycan on the surface of bladder cancer cell lines and human bladder tumor tissues. We then constructed a lectin-drug conjugate by linking concanavalin A (ConA) - a lectin that specifically binds to mannose, with EPI through a pH-sensitive linker. This ConA-EPI conjugate conferred EPI with mannose-targeting ability and selectively internalized cancer cells in vitro. This conjugate showed selective cytotoxicity to cancer cells in vitro and better antitumor activity in an orthotopic mouse model of bladder cancer. Our lectin-drug conjugation strategy makes targeted intravesical chemotherapy of bladder cancer possible.


Assuntos
Neoplasias da Bexiga Urinária , Administração Intravesical , Animais , Antibióticos Antineoplásicos , Concanavalina A/farmacologia , Epirubicina/efeitos adversos , Humanos , Manose , Camundongos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
10.
Phys Rev Lett ; 128(2): 027401, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35089752

RESUMO

We experimentally explore the fingerprint of the microscopic electron dynamics in second-order harmonic generation (SHG). It is shown that the interbond electron hopping induces a novel source of nonlinear polarization and plays an important role even when the driving laser intensity is 2 orders of magnitude lower than the characteristic atomic field. Our model predicts anomalous anisotropic structures of the SHG yield contributed by the interbond electron hopping, which is identified in our experiments with ZnO crystals. Moreover, a generalized second-order susceptibility with an explicit form is proposed, which provides a unified description in both the weak and strong field regimes. Our work reveals the nonlinear responses of materials at the electron scale and extends the nonlinear optics to a previously unexplored regime, where the nonlinearity related to the interbond electron hopping becomes dominant. It paves the way for realizing controllable nonlinearity on an ultrafast time scale.

11.
Inorg Chem ; 60(23): 17649-17656, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34747602

RESUMO

The reactions of laser-ablated Ce, Sm, Eu, and Lu atoms with acetonitrile were studied by matrix infrared spectra in a neon matrix, and M←NCCH3, M-η2-(NC)-CH3, and CN-M-CH3 were identified with isotopic substitution and quantum chemical calculations. The major product is the insertion complex (CN-M-CH3), while the end-on and side-on complexes (M←NCCH3 and M-η2-(NC)-CH3) are also trapped in the matrix. The CCN antisymmetric stretching mode for Ce-η2-(NC)-CH3 was observed at 1536.9 cm-1, which is much lower than the same modes observed for other lanthanides. NBO analysis reveals that Ce exhibits a remarkable 4f-orbital contribution in bonding to N and to C, reconfirming an active 4f-orbital contribution of cerium in bonding in the side-on complex, while the 4f contributions of Sm and Eu to the M-N and M-C bonds are much lower and the 4f orbital of Lu is not involved in bonding.

12.
PhytoKeys ; 180: 65-71, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393577

RESUMO

The new series ElatostemasectionWeddellia series Xingyiensia L.D. Duan & D.H. Yin (Urticaceae) is described. In addition, its new species Elatostemaxingyiense L.D. Duan & D.H. Yin, endemic to Guizhou Province, is also described and illustrated with photographs. The new series is morphologically similar to series Melanocarpa W.T. Wang and series Sublinearia W.T. Wang. The new species is most similar to E.melanocarpum, E.sublineare, E.obscurinerve, E.langicuspe and E.youyangense in morphology, but can be visibly distinguished by a combination of characters, including leaf vein, male inflorescences, female inflorescences and persistent tepals.

13.
Inorg Chem ; 60(15): 11466-11473, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34291929

RESUMO

Reactions of MH2 (M = Sr, Ba) with CO2 were explored in pure parahydrogen at 3.5 K using matrix isolation infrared spectroscopy and quantum chemical calculations. The formate complex HM(η2-O2CH) and formic acid complex (MH2)(HCOOH) were trapped and identified by isotopic substitutions and density functional theory (DFT) frequency calculations. Natural population analysis and the CO2 reduction mechanism demonstrate that hydride ion transfer from a metal hydride to a CO2 moiety facilitates the stabilization of such complexes.

14.
Opt Express ; 29(11): 17387-17397, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154283

RESUMO

We theoretically investigate the photocurrents injected in gapped graphene by the orthogonally polarized two-color laser field. Depending on the relative phase, the photocurrents can be coherently controlled by deforming the electron trajectory in the reciprocal space. Under the same field strength, the peak photocurrent in the orthogonally polarized two-color field is about 20 times larger than that for linearly polarized light, and about 3.6 times for elliptically polarized light. The enhancement of the photocurrent can be attributed to an obvious asymmetric distribution of the real population in the reciprocal space, which is sensitive to the waveform of the laser field and related to the quantum interference between the electron trajectories. Our work provides a noncontact method to effectively enhance the injected current in graphene.

15.
Phys Rev Lett ; 126(18): 187401, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018768

RESUMO

Previously, the strong field processes in solids have always been explained by the single-active-electron (SAE) model with a frozen core excluding the fluctuation of background electrons. In this work, we demonstrate the strong field induced dynamic core polarization effect and propose a model for revealing its role in high harmonic generation (HHG) from solids. We show that the polarized core induces an additional polarization current beyond the SAE model based on the frozen cores. It gives a new mechanism for HHG and leads to new anisotropic structures, which are experimentally observed with MgO. Our experiments indicate that the influences of dynamic core polarization on HHG are obvious for both linearly and elliptically polarized laser fields. Our work establishes the bridge between the HHG and the dynamic changes of the effective many-electron interaction in solids, which paves the way to probe the ultrafast electron dynamics.

16.
Inorg Chem ; 60(11): 7687-7696, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34029065

RESUMO

On reacting laser-ablated manganese or iron difluorides with O2 or O3 during codeposition in solid neon or argon, infrared absorptions of several new metal oxo-fluoride molecules, including OMF2, (η1-O2)MF2, (η2-O3)MF2, (η1-O2)2MF2 (M = Mn and Fe), and O2MnF, have been observed. Quantum chemical density functional and multiconfiguration wavefunction calculations have been applied to characterize these new products by their geometric and electronic structures, vibrations, charges, and bonding. The assignment of the main vibrational absorptions as dominant symmetric or antisymmetric M-F or M-O stretching modes is confirmed by oxygen isotopic shifts and quantum chemical calculations of frequencies and thermal stabilities. The tendency of Fe to form polyoxygen complexes in lower oxidation states than the preceding element Mn is affirmed experimentally and supported theoretically. The M-F stretching frequencies of the isolated metal oxo-fluorides may provide a scale for the local charge on the MF2 sites in active energy conversion systems. The study of these species provides insights for understanding the trend of oxidation state changes across the transition-metal series.

17.
Chem Commun (Camb) ; 57(18): 2301-2304, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33533348

RESUMO

Manganese formate complexes, HMn(η2-O2CH) and Mn(η2-O2CH), are formed through MnH2 and MnH reactions with CO2 in solid parahydrogen and identified by matrix infrared spectroscopy with the basis of isotopic substitutions and theoretical frequency calculations. The reaction mechanism has been proposed that the reaction proceeds by concerted hydride ion transfer.

18.
Autophagy ; 17(11): 3592-3606, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33629929

RESUMO

Glioma is the most common primary malignant brain tumor with poor survival and limited therapeutic options. The non-psychoactive phytocannabinoid cannabidiol (CBD) has been shown to be effective against glioma; however, the molecular target and mechanism of action of CBD in glioma are poorly understood. Here we investigated the molecular mechanisms underlying the antitumor effect of CBD in preclinical models of human glioma. Our results showed that CBD induced autophagic rather than apoptotic cell death in glioma cells. We also showed that CBD induced mitochondrial dysfunction and lethal mitophagy arrest, leading to autophagic cell death. Mechanistically, calcium flux induced by CBD through TRPV4 (transient receptor potential cation channel subfamily V member 4) activation played a key role in mitophagy initiation. We further confirmed TRPV4 levels correlated with both tumor grade and poor survival in glioma patients. Transcriptome analysis and other results demonstrated that ER stress and the ATF4-DDIT3-TRIB3-AKT-MTOR axis downstream of TRPV4 were involved in CBD-induced mitophagy in glioma cells. Lastly, CBD and temozolomide combination therapy in patient-derived neurosphere cultures and mouse orthotopic models showed significant synergistic effect in both controlling tumor size and improving survival. Altogether, these findings showed for the first time that the antitumor effect of CBD in glioma is caused by lethal mitophagy and identified TRPV4 as a molecular target and potential biomarker of CBD in glioma. Given the low toxicity and high tolerability of CBD, we therefore propose CBD should be tested clinically for glioma, both alone and in combination with temozolomide.Abbreviations: 4-PBA: 4-phenylbutyrate; AKT: AKT serine/threonine kinase; ATF4: activating transcription factor 4; Baf-A1: bafilomycin A1; CANX: calnexin; CASP3: caspase 3; CAT: catalase; CBD: cannabidiol; CQ: chloroquine; DDIT3: DNA damage inducible transcript 3; ER: endoplasmic reticulum; GBM: glioblastoma multiforme; GFP: green fluorescent protein; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MTOR: mechanistic target of rapamycin kinase; PARP1: poly(ADP-ribose) polymerase; PINK1: PTEN induced kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; SLC8A1: solute carrier family 8 member A1; SQSTM1: sequestosome 1; TCGA: The cancer genome atlas; TEM: transmission electron microscopy; TMZ: temozolomide; TRIB3: tribbles pseudokinase 3; TRPC: transient receptor potential cation channel subfamily C; TRPV4: transient receptor potential cation channel subfamily V member 4.


Assuntos
Canabidiol/uso terapêutico , Glioma/tratamento farmacológico , Mitofagia/efeitos dos fármacos , Canais de Cátion TRPV/metabolismo , Animais , Antineoplásicos Alquilantes/farmacologia , Morte Celular Autofágica/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Canabidiol/farmacologia , Linhagem Celular Tumoral , Glioma/metabolismo , Glioma/patologia , Humanos , Masculino , Camundongos , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Transplante de Neoplasias , Canais de Cátion TRPV/fisiologia , Temozolomida/farmacologia
19.
J Biol Inorg Chem ; 26(1): 123-133, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33449164

RESUMO

LCN2 (Lipocalins) was first identified as iron transporter through associating with its siderophores and also involved in many cancer metastases, but its function is still paradoxical. We questioned that whether LCN2 might also associate exogenous iron chelator as does in inherent way and the association may influence their respective function. To address this issue, we investigated the effect of LCN2 on action of DpdtC (2,2'-dipyridine ketone hydrazone dithiocarbamte), an iron chelator in proliferation and metastasis-related gene expression. The results showed that exogenous LCN2 and DpdtC could inhibit growth of HepG2 cells, while the combination treatment enhanced their inhibitory effect both in proliferation and colony formation. This encouraged us to investigate the effect of the interaction on metastasis-related gene expression. The results revealed that both LCN2 and DpdtC impaired the wound healing of HepG2, but the inhibitory effect of DpdtC was significantly enhanced upon association with LCN2. Undergoing epithelium-mesenchymal transition (EMT) is a crucial step for cancer metastasis, LCN2 and DpdtC had opposite effects on EMT markers, the binding of DpdtC to LCN2 significantly weakened the regulation of it (or its iron chelate) on EMT markers. To insight into the interaction between LCN2 and DpdtC-iron, fluorescence titration and molecular docking were performed to obtain the association constant (~ 104 M-1) and thermodynamic parameters (ΔG = - 26.10 kJ/mol). Importantly this study provided evidence that siderophores-loading state of LCN2 may influence its function, which be helpful for understanding the contradictory role of LCN2 in the metastasis of cancer.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Ditiocarb/análogos & derivados , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Quelantes de Ferro/farmacologia , Lipocalina-2/metabolismo , Autofagia/efeitos dos fármacos , Ditiocarb/farmacologia , Ferritinas/metabolismo , Células Hep G2 , Humanos , Hidrazonas/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Tiocarbamatos/farmacologia , Canais de Potencial de Receptor Transitório
20.
Mol Genet Genomic Med ; 8(12): e1521, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33155773

RESUMO

OBJECTIVE: This study aimed to identify critical genes involved in the tumor biology of lung cancer via datamining of The Cancer Genome Atlas (TCGA) with special focus on gene copy number variation. METHODS: Genomic deletion and amplification were analyzed with cBioportal online tools. Relative expression of Cyclin Dependent Kinase Inhibitor 2A (CDKN2A) was analyzed by both real-time polymerase chain reaction (PCR) and Western blot. The abundance of methylthioadenosine phosphorylase (MTAP) and epithelial-mesenchymal transition markers were analyzed by real-time PCR. Cell proliferation was determined by cell counting kit-8 method and cell viability was measured with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The cell migration and invasion were measured with transwell chamber assay, and migrative capacity was further evaluated by wound healing assay. RESULTS: We found the frequent loss of CDKN2A was associated with its downregulation in lung cancer, and siRNA-mediated CDNKN2A knockdown significantly stimulated cell proliferation, invasion, and migration. Mechanistically, we unraveled that MTAP, which was positively correlated with CDKN2A, predominantly mediated the antitumoral function of CDKN2A in lung cancer. CONCLUSION: Our study consolidated the involvement of CDKN2A-MTAP signaling in the context of lung cancer.


Assuntos
Biomarcadores Tumorais/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias Pulmonares/genética , Células A549 , Biomarcadores Tumorais/deficiência , Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Cromossomos Humanos Par 9/genética , Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Transição Epitelial-Mesenquimal , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Purina-Núcleosídeo Fosforilase/metabolismo
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