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1.
Mol Cell ; 62(4): 507-19, 2016 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-27203177

RESUMEN

UV-induced DNA damage, a major risk factor for skin cancers, is primarily repaired by nucleotide excision repair (NER). UV radiation resistance-associated gene (UVRAG) is a tumor suppressor involved in autophagy. It was initially isolated as a cDNA partially complementing UV sensitivity in xeroderma pigmentosum (XP), but this was not explored further. Here we show that UVRAG plays an integral role in UV-induced DNA damage repair. It localizes to photolesions and associates with DDB1 to promote the assembly and activity of the DDB2-DDB1-Cul4A-Roc1 (CRL4(DDB2)) ubiquitin ligase complex, leading to efficient XPC recruitment and global genomic NER. UVRAG depletion decreased substrate handover to XPC and conferred UV-damage hypersensitivity. We confirmed the importance of UVRAG for UV-damage tolerance using a Drosophila model. Furthermore, increased UV-signature mutations in melanoma correlate with reduced expression of UVRAG. Our results identify UVRAG as a regulator of CRL4(DDB2)-mediated NER and suggest that its expression levels may influence melanoma predisposition.


Asunto(s)
Autofagia/efectos de la radiación , Daño del ADN , Reparación del ADN/efectos de la radiación , Proteínas de Unión al ADN/metabolismo , Melanoma Experimental/enzimología , Neoplasias Cutáneas/enzimología , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Rayos Ultravioleta , Animales , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Proteínas Cullin/genética , Proteínas Cullin/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Drosophila melanogaster/genética , Drosophila melanogaster/efectos de la radiación , Activación Enzimática , Células HEK293 , Células HeLa , Humanos , Melanoma Experimental/genética , Melanoma Experimental/patología , Proteolisis , Interferencia de ARN , Retina/enzimología , Retina/efectos de la radiación , Transducción de Señal/efectos de la radiación , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Factores de Tiempo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transfección , Proteínas Supresoras de Tumor/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
2.
J Exp Bot ; 73(7): 2222-2237, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-34919655

RESUMEN

Cold stress is a major environmental factor affecting plant growth and development. Although some plants have developed resistance to cold stress, the molecular mechanisms underlying this process are poorly understood. Using genome-wide association mapping with 200 cotton accessions collected from different regions, we identified variations in the short chain alcohol dehydrogenase gene, GhSAD1, that responds to cold stress. Virus-induced gene silencing and overexpression in Arabidopsis revealed that GhSAD1 fulfils important roles in cold stress responses. Ectopic expression of a haploid genotype of GhSAD1 (GhSAD1HapB) in Arabidopsis increased cold tolerance. Silencing of GhSAD1HapB resulted in a decrease in abscisic acid (ABA) content. Conversely, overexpression of GhSAD1HapB increased ABA content. GhSAD1HapB regulates cold stress responses in cotton through modulation of C-repeat binding factor activity, which regulates ABA signalling. GhSAD1HapB induces the expression of COLD-REGULATED (COR) genes and increases the amount of metabolites associated with cold stress tolerance. Overexpression of GhSAD1HapB partially complements the phenotype of the Arabidopsis ABA2 mutant, aba2-1. Collectively, these findings increase our understanding of the mechanisms underlying GhSAD1-mediated cold stress responses in cotton.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Frío , Regulación de la Expresión Génica de las Plantas , Estudio de Asociación del Genoma Completo , Plantas Modificadas Genéticamente/genética , Estrés Fisiológico
3.
Proc Natl Acad Sci U S A ; 115(33): E7728-E7737, 2018 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-30061422

RESUMEN

UV-induced cell pigmentation represents an important mechanism against skin cancers. Sun-exposed skin secretes α-MSH, which induces the lineage-specific transcriptional factor MITF and activates melanogenesis in melanocytes. Here, we show that the autophagic tumor suppressor UVRAG plays an integral role in melanogenesis by interaction with the biogenesis of lysosome-related organelles complex 1 (BLOC-1). This interaction is required for BLOC-1 stability and for BLOC-1-mediated cargo sorting and delivery to melanosomes. Absence of UVRAG dispersed BLOC-1 distribution and activity, resulting in impaired melanogenesis in vitro and defective melanocyte development in zebrafish in vivo. Furthermore, our results establish UVRAG as an important effector for melanocytes' response to α-MSH signaling as a direct target of MITF and reveal the molecular basis underlying the association between oncogenic BRAF and compromised UV protection in melanoma.


Asunto(s)
Melaninas/biosíntesis , Melanosomas/metabolismo , Pigmentación de la Piel/efectos de la radiación , Proteínas Supresoras de Tumor/metabolismo , Rayos Ultravioleta , Animales , Células HEK293 , Humanos , Melaninas/genética , Melanoma/genética , Melanoma/metabolismo , Melanosomas/genética , Factor de Transcripción Asociado a Microftalmía/genética , Factor de Transcripción Asociado a Microftalmía/metabolismo , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteínas Supresoras de Tumor/genética , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
4.
Mol Carcinog ; 58(11): 2149-2160, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31448838

RESUMEN

Autophagy is a self-proteolytic process that degrades intracellular material to maintain cellular homeostasis. Transcription factor EB (TFEB) is the master activator that regulates the transcription of genes involved in autophagy and lysosomal biogenesis. However, the cotranscriptional factors of TFEB are rarely identified. Here, we found that Yin Yang 1 (YY1) regulated autophagy and lysosome biogenesis in melanoma cells. YY1 cooperates with TFEB to regulate autophagy through controlling the transcription of autophagy and lysosome biogenesis related genes. Moreover, suppression of YY1 enhanced the antitumor efficiency of vemurafenib both in vitro and in vivo. Collectively, these studies identify YY1 as a novel cotranscription factor of TFEB in regulating autophagy and lysosomal functions and suggest YY1 could be a therapeutic target in cancer treatment.


Asunto(s)
Autofagia/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Melanoma/genética , Factor de Transcripción YY1/genética , Animales , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Xenoinjertos , Humanos , Lisosomas/genética , Melanoma/patología , Ratones , Plásmidos/genética
5.
Opt Express ; 27(13): 18585-18600, 2019 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-31252799

RESUMEN

Surface phonon polaritons (SPhPs) in polar dielectrics are potential candidates for infrared nanophotonics due to their low optical loss and long phonon life-time. However, the small confinement factors of bulk SPhPs, limits their applications that require small footprint and strong light-matter interaction. Here, we report that ultrathin van der Waals dielectrics (e.g., MoS2 and h-BN) on Silicon Carbide enable ultra-confined dielectric tailored surface phonon polaritons (d-SPhPs) where the confinement factor can exceed 100. By creating a heterostructure of these vdW dielectrics with graphene, the d-SPhPs can hybridize with graphene plasmons which can be electrically tuned. By subwavelength patterning of the vdW dielectrics, these hybrid polaritons can be localized into ultra-small antenna volumes (λ03/vantenna 3~1003) with high-quality factor resonances (Q~85). Further, electric gating of graphene enables active tunability of these localized resonances which results in an electro-optic modulator with modulation depth exceeding 95%. Our report of manipulating and controlling ultra-confined SPhPs in van der Waals heterostructures, serves as a possible route for non-plasmonic platforms for infrared photodetectors, modulators and sensors.

6.
Int J Mol Sci ; 20(16)2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-31404956

RESUMEN

(1) Background: Upland cotton (Gossypium hirsutum L.) is the most important natural fiber worldwide, and it is extensively planted and plentifully used in the textile industry. Major cotton planting regions are frequently affected by abiotic stress, especially drought stress. Drought resistance is a complex, quantitative trait. A genome-wide association study (GWAS) constitutes an efficient method for dissecting the genetic architecture of complex traits. In this study, the drought resistance of a population of 316 upland cotton accessions was studied via GWAS. (2) Methods: GWAS methodology was employed to identify relationships between molecular markers or candidate genes and phenotypes of interest. (3) Results: A total of 8, 3, and 6 SNPs were associated with the euphylla wilting score (EWS), cotyledon wilting score (CWS), and leaf temperature (LT), respectively, based on a general linear model and a factored spectrally transformed linear mixed model. For these traits, 7 QTLs were found, of which 2 each were located on chromosomes A05, A11, and D03, and of which 1 was located on chromosome A01. Importantly, in the candidate regions WRKY70, GhCIPK6, SnRK2.6, and NET1A, which are involved in the response to abscisic acid (ABA), the mitogen-activated protein kinase (MAPK) signaling pathway and the calcium transduction pathway were identified in upland cotton at the seedling stage under drought stress according to annotation information and linkage disequilibrium (LD) block analysis. Moreover, RNA sequencing analysis showed that WRKY70, GhCIPK6, SnRK2.6, and NET1A were induced by drought stress, and the expression of these genes was significantly different between normal and drought stress conditions. (4) Conclusions: The present study should provide some genomic resources for drought resistance in upland cotton. Moreover, the germplasm of the different phenotypes, the detected SNPs and, the potential candidate genes will be helpful for molecular marker-assisted breeding studies about increased drought resistance in upland cotton.


Asunto(s)
Gossypium/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Plantones/genética , Adaptación Fisiológica , Sequías , Regulación de la Expresión Génica de las Plantas , Estudio de Asociación del Genoma Completo , Gossypium/fisiología , Desequilibrio de Ligamiento , Plantones/fisiología , Estrés Fisiológico
7.
Mol Carcinog ; 57(11): 1566-1576, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30035324

RESUMEN

Ferroptosis is a recently recognized form of regulated cell death driven by lipid-based reactive oxygen species (ROS) accumulation. However, the molecular mechanisms of ferroptosis regulation are still largely unknown. Here we identified a novel miRNA, miR-9, as an important regulator of ferroptosis by directly targeting GOT1 in melanoma cells. Overexpression of miR-9 suppressed GOT1 by directly binding to its 3'-UTR, which subsequently reduced erastin- and RSL3-induced ferroptosis. Conversely, suppression of miR-9 increased the sensitivity of melanoma cells to erastin and RSL3. Importantly, anti-miR-9 mediated lipid ROS accumulation and ferroptotic cell death could be abrogated by inhibiting glutaminolysis process. Taken together, our findings demonstrate that miR-9 regulates ferroptosis by targeting GOT1 in melanoma cells, illustrating the important role of miRNA in ferroptosis.


Asunto(s)
Aspartato Aminotransferasa Citoplasmática/genética , Regulación Neoplásica de la Expresión Génica , Hierro/metabolismo , Melanoma/genética , Melanoma/metabolismo , MicroARNs/genética , Interferencia de ARN , Regiones no Traducidas 3' , Carbolinas/farmacología , Línea Celular Tumoral , Supervivencia Celular/genética , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Melanoma/patología , Modelos Biológicos , Piperazinas/metabolismo
8.
Dev Biol ; 377(1): 166-76, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23453925

RESUMEN

Hedgehog (Hh) proteins act as morphogens in a variety of developmental contexts to control cell fates and growth in a concentration-dependent manner. Therefore, secretion, distribution, and reception of Hh proteins must be tightly regulated and deregulation of these processes contributes to numerous human diseases. Brother of ihog (Boi) and its close relative Ihog (Interference hedgehog) are cell surface proteins that act as Hh co-receptors required for Hh signaling response and cell-surface maintenance of Hh protein. MicroRNAs (miRNAs) are a group of widely expressed 21-23 nucleotides non-coding RNAs that repress gene function through interactions with target mRNAs. Here, we have identified a novel miRNA, miR-932, as an important regulator for Boi. We show that overexpression of miR-932 in the wing disc can enhance Hh signaling strength, but reduce its signaling range, a phenotype similar to that of boi knockdown. In both in vivo sensor assay and in vitro luciferase assay, miR-932 can suppress Boi by directly binding to its 3'UTR. Meanwhile, down-regulation of miR-932 by sponge elevates the protein level of Boi, confirming that miR-932 is an in vivo regulator of Boi expression. Further, we demonstrate that miR-932 can block Hh signaling when co-expressed with ihog-RNAi. Moreover, we find that other predicted miRNAs of Boi fail to suppress it as strong as miR-932. Taken together, our data demonstrate that miR-932 can modulate Hh activity by specifically targeting Boi in Drosophila, illustrating the important roles of miRNAs in fine regulation of the Hh signaling pathway.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas Hedgehog/metabolismo , MicroARNs/metabolismo , Receptores de Superficie Celular/metabolismo , Transducción de Señal/genética , Regiones no Traducidas 3'/genética , Animales , Secuencia de Bases , Proteínas Portadoras/genética , Proteínas de Drosophila/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , MicroARNs/genética , Datos de Secuencia Molecular , Interferencia de ARN , Alas de Animales/citología , Alas de Animales/crecimiento & desarrollo , Alas de Animales/metabolismo
9.
Zhonghua Yi Xue Za Zhi ; 94(5): 376-8, 2014 Feb 11.
Artículo en Zh | MEDLINE | ID: mdl-24746087

RESUMEN

OBJECTIVE: To explore the outcomes of individualized neurosurgical treatments of spastic cerebral palsy. METHODS: A total of 452 spastic cerebral palsy patients undergoing microneurosurgery during March 2006 and December 2011 were retrospectively analyzed. Performed on the basis of clinical manifestations, comprehensive procedures included selective cutting of neck or lumbosacral dorsal root ganglia (SPR, n = 182) for multiple muscle spasm, selective peripheral neurotomy (SPN, n = 270) for focal muscle spasm, line tendon lengthening or cutting and orthopedic surgery (n = 116) for tendon contracture plus limb deformities and carotid artery adventitia endarterectomy (n = 46) for salivation plus athetoid. RESULTS: The average follow-up period was 18 (10-24) months. The limb spasm relief rate of SPR was 95.6% and that of SPN 98.3%. And the postoperative symptom improvement rate of common carotid arterial adventitia stripping was 91.3%. There were 8 cases (4.4%) of recurrent spasticity after SPR and 28 (10.4%) after SPN. CONCLUSION: Offering individualized microsurgical treatments on the basis of clinical manifestations is essential for patients with spastic cerebral palsy.


Asunto(s)
Parálisis Cerebral/cirugía , Desnervación/métodos , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
10.
Development ; 137(12): 2033-44, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20501592

RESUMEN

Hedgehog (Hh) acts as a morphogen in various developmental contexts to specify distinct cell fates in a concentration-dependent manner. Hh signaling is regulated by two conserved cell-surface proteins: Ig/fibronectin superfamily member Interference hedgehog (Ihog) and Dally-like (Dlp), a glypican that comprises a core protein and heparan sulfate glycosaminoglycan (GAG) chains. Here, we show in Drosophila that the Dlp core protein can interact with Hh and is essential for its function in Hh signaling. In wing discs, overexpression of Dlp increases short-range Hh signaling while reducing long-range signaling. By contrast, Ihog has biphasic activity in Hh signaling in cultured cells: low levels of Ihog increase Hh signaling, whereas high levels decrease it. In wing discs, overexpression of Ihog represses high-threshold targets, while extending the range of low-threshold targets, thus showing opposite effects to Dlp. We further show that Ihog and its family member Boi are required to maintain Hh on the cell surface. Finally, Ihog and Dlp have complementary expression patterns in discs. These data led us to propose that Dlp acts as a signaling co-receptor. However, Ihog might not act as a classic co-receptor; rather, it may act as an exchange factor by retaining Hh on the cell surface, but also compete with the receptor for Hh binding.


Asunto(s)
Glipicanos/metabolismo , Proteínas Hedgehog/metabolismo , Transducción de Señal/fisiología , Alas de Animales/metabolismo , Animales , Células Cultivadas , Drosophila/genética , Drosophila/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Glicosaminoglicanos/genética , Glicosaminoglicanos/metabolismo , Glipicanos/genética , Proteínas Hedgehog/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Transducción de Señal/genética , Alas de Animales/citología
11.
Int J Mol Med ; 51(5)2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37026507

RESUMEN

Following the publication of the above paper, it was drawn to the Editor's attention by a concerned reader that the α­tubulin protein bands shown in Fig. 2A on p. 689 were strikingly similar to data appearing in different form in the following paper: Tian R, Li Y and Gao M: Shikonin causes cell­cycle arrest and induces apoptosis by regulating the EGFR­NF­κB signalling pathway in human epidermoid carcinoma A431 cells. Biosci Rep 35: e00189, 2015. Moreover, there were a pair of overlapping data panels shown in the cell invasion and migration assay data in Fig. 5B on p. 692, one identified instance of western blot data being shared between Figs. 3D and 4F, and a pair of overlapping data panels in Fig. 5D, such that all these data, which were intended to have shown the results from differently performed experiments, may have been derived from a smaller number of original sources. Owing to the fact that the contentious data in the above article were already under consideration for publication prior to its submission to International Journal of Molecular Medicine and an overall lack of confidence in the presented data, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a satisfactory reply. The Editor apologizes to the readership for any inconvenience caused. [International Journal of Molecular Medicine 36: 685­697, 2015; DOI: 10.3892/ijmm.2015.2292].

12.
Cell Death Differ ; 29(9): 1850-1863, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35338333

RESUMEN

Ferroptosis, a novel form of regulated cell death induced by iron-dependent lipid peroxidation, plays an essential role in the development and drug resistance of tumors. Long noncoding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NEAT1) has been reported to be involved in the regulation of cell cycle, proliferation, apoptosis, and migration of tumor cells. However, the function and molecular mechanism of NEAT1 in regulating ferroptosis in tumors remain unclear. Here, we found that ferroptosis inducers erastin and RSL3 increased NEAT1 expression by promoting the binding of p53 to the NEAT1 promoter. Induced NEAT1 promoted the expression of MIOX by competitively binding to miR-362-3p. MIOX increased ROS production and decreased the intracellular levels of NADPH and GSH, resulting in enhanced erastin- and RSL3-induced ferroptosis. Importantly, overexpression of NEAT1 increased the anti-tumor activity of erastin and RSL3 by enhancing ferroptosis both in vitro and in vivo. Collectively, these data suggest that NEAT1 plays a novel and indispensable role in ferroptosis by regulating miR-362-3p and MIOX. Considering the clinical findings that HCC patients are insensitive to chemotherapy and immunotherapy, ferroptosis induction may be a promising therapeutic strategy for HCC patients with high NEAT1 expression.


Asunto(s)
Carcinoma Hepatocelular , Ferroptosis , Inositol-Oxigenasa/metabolismo , Neoplasias Hepáticas , MicroARNs , ARN Largo no Codificante/genética , Línea Celular Tumoral , Proliferación Celular/genética , Ferroptosis/genética , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo
13.
Materials (Basel) ; 15(20)2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36295318

RESUMEN

To investigate the relationship between the dislocation configuration and the grain refinement in the NV E690 cladding layer caused by laser shock peening, NV E690 high-strength steel powder was used to repair prefabricated pits in samples of 690 high-strength steel by laser cladding, where the laser shock peening of the cladding layer was performed by laser shock at different power densities. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy were used to observe the microstructures of these samples before and after the laser shock process. The results showed that the metallurgical bonding between the cladding layer and the substrate after laser cladding repair was good. When the laser power density was 4.77 GW/cm2, multiple edge dislocations, dislocation dipoles, and extended dislocations were distributed over the cladding layer. When the laser power density was 7.96 GW/cm2, a geometrically necessary dislocation divided the large original grain into two subgrains with different orientations. When the laser power density was 11.15 GW/cm2, geometric dislocations divided the entire large grain into fine grains. The grain refinement model of the NV E690 cladding layer, when treated by laser shock peening, can describe the grain refinement process induced by the dislocation movement of this cladding layer.

14.
J Adv Res ; 37: 209-219, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35475278

RESUMEN

Introduction: The SARS-CoV-2 pandemic has endangered global health, the world economy, and societal values. Despite intensive measures taken around the world, morbidity and mortality remain high as many countries face new waves of infection and the spread of new variants. Worryingly, more and more variants are now being identified, such as 501Y.V1 (B.1.1.7) in the UK, 501Y.V2 (B.1.351) in South Africa, 501Y.V3 in Manaus, Brazil, and B.1.617/B.1.618 in India, which could lead to a severe epidemic rebound. Moreover, some variants have a stronger immune escape ability. To control the new SARS-CoV-2 variant, we may need to develop and redesign new vaccines repeatedly. So it is important to investigate how our immune system combats and responds to SARS-CoV-2 infection to develop safe and effective medical interventions. Objectives: In this study, we performed a longitudinal and proteome-wide analysis of antibodies in the COVID-19 patients to revealed some immune processes of COVID-19 patients against SARS-CoV-2 and found some dominant epitopes of a potential vaccine. Methods: Microarray assay, Antibody depletion assays, Neutralization assay. Results: We profiled a B-cell linear epitope landscape of SARS-CoV-2 and identified the epitopes specifically recognized by either IgM, IgG, or IgA. We found that epitopes more frequently recognized by IgM are enriched in non-structural proteins. We further identified epitopes with different immune responses in severe and mild patients. Moreover, we identified 12 dominant epitopes eliciting antibodies in most COVID-19 patients and identified five key amino acids of epitopes. Furthermore, we found epitope S-82 and S-15 are perfect immunogenic peptides and should be considered in vaccine design. Conclusion: This data provide useful information and rich resources for improving our understanding of viral infection and developing a novel vaccine/neutralizing antibodies for the treatment of SARS-CoV-2.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales , Epítopos , Humanos , Inmunidad Humoral , Inmunoglobulina M , Proteoma
15.
Oncol Lett ; 22(3): 657, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34386079

RESUMEN

Melanoma, the most aggressive skin cancer, is mainly treated with BRAF inhibitors or immunotheareapy. However, most patients who initially responded to BRAF inhibitors or immunotheareapy become resistant following relapse. Ferroptosis is a form of regulated cell death characterized by its dependence on iron ions and the accumulation of lipid reactive oxygen species (ROS). Recent studies have demonstrated that ferroptosis is a good method for tumor treatment, and iron homeostasis is closely associated with ferroptosis. Iron regulatory protein (IRP)1 and 2 play important roles in maintaining iron homeostasis, but their functions in ferroptosis have not been investigated. The present study reported that the expression of IRP1 and IRP2 was increased by the ferroptosis inducers erastin and RSL3 in melanoma cells. Depletion of IRP1 significantly suppressed erastin- and RSL3-induced ferroptosis. IRP2 had a weak effect but could enhance the promoting function of IRP1 on ferroptosis. Further, erastin and RSL3 promoted the transition of aconitase 1 to IRP1, which regulated downstream iron metabolism proteins, including transferrin receptor (TFRC), ferroportin (FPN) and ferritin heavy chain 1 (FTH1). Moreover, overexpression of TFRC and knockdown of FPN and FTH1 significantly promoted erastin- and RSL3-induced ferroptosis in IRP1 knockdown melanoma cells. Collectively, the present findings indicate that IRP1 plays an essential role in erastin- and RSL3-induced ferroptosis by regulating iron homeostasis.

16.
Oncol Lett ; 20(5): 182, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32934749

RESUMEN

The present study aimed to investigate the expression and clinical significance of solute carrier family 17 member 9 (SLC17A9) in cancer tissues of patients with hepatocellular carcinoma (HCC). Ninety-eight patients with HCC were admitted to our hospital from January 2010 to December 2014. Their clinical data was retrospectively analyzed. The expression of SLC17A9 in HCC cancer tissues was detected by immunohistochemistry. Kaplan-Meier curve, log-rank test and Cox proportional hazard model analysis were used to analyze the tumor-free survival rate and overall survival rate. SLC17A9 expression was associated with Edmondson grade (P=0.04) and distant metastasis (P=0.03). The tumor-free survival (P=0.03) and overall survival (P=0.01) of SLC17A9-high expression patients were significantly lower than those in SLC17A9-low expression patients. Multivariate analysis revealed that SLC17A9 expression (HR, 0.77; 95% CI, 0.27-2.47, P=0.02) was an independent risk factor for tumor-free survival in patients with HCC, and the expression of SLC17A9 (HR, 1.81; 95% CI, 0.99-3.77, P=0.04) was an independent risk factor for overall survival in patients with HCC. In conclusion, SLC17A9 can be used as a new molecular marker to predict the poor prognosis of patients with HCC.

17.
Cell Signal ; 72: 109633, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32283255

RESUMEN

Ferroptosis is a regulated form of cell death characterized by the iron-dependent accumulation of lipid hydroperoxides. Ceruloplasmin (CP) is a glycoprotein that plays an essential role in iron homeostasis. However, whether CP regulates ferroptosis has not been reported. Here, we show that CP suppresses ferroptosis by regulating iron homeostasis in hepatocellular carcinoma (HCC) cells. Depletion of CP promoted erastin- and RSL3-induced ferroptotic cell death and resulted in the accumulation of intracellular ferrous iron (Fe2+) and lipid reactive oxygen species (ROS). Moreover, overexpression of CP suppressed erastin- and RSL3-induced ferroptosis in HCC cells. In addition, a novel frameshift mutation (c.1192-1196del, p.leu398serfs) of CP gene newly identified in patients with iron accumulation and neurodegenerative diseases lost its ability to regulate iron homeostasis and thus failed to participate in the regulation of ferroptosis. Collectively, these data suggest that CP plays an indispensable role in ferroptosis by regulating iron metabolism and indicate a potential therapeutic approach for hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Ceruloplasmina/metabolismo , Ferroptosis , Homeostasis , Hierro/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Antígenos CD/metabolismo , Carbolinas/farmacología , Proteínas de Transporte de Catión/metabolismo , Línea Celular Tumoral , Ferroptosis/efectos de los fármacos , Mutación del Sistema de Lectura/genética , Homeostasis/efectos de los fármacos , Humanos , Modelos Biológicos , Piperazinas/farmacología , Receptores de Transferrina/metabolismo
18.
Sci Prog ; 103(2): 36850420925227, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32515647

RESUMEN

To investigate the performance of engine cooling water pump in automobile with variable rotating speed, experimental tests and numerical simulation are carried out on an engine cooling water pump under the rotating speed of 2650, 2960, 3700, and 4300 r/min. The hydraulic performance under 3700 r/min rotating speed and the cavitation performance under 340 L/min flow rate are tested and analyzed. The predicted results agree well with the experimental results, indicating that the simulation has high accuracy. The results show that the head of engine cooling water pump increases gradually and the best-effective region moves toward high flow rate condition with the increase in rotating speed. The augment of rotating speed would deteriorate the internal flow fields and causes more energy losses, which is due to the increase in tip leakage flow and enhancement of rotor-stator interaction effects. And, the rotor-stator interaction effect is sensitive to the temperature under various rotating speeds. Furthermore, the required net positive suction head increases with the increase in rotational speed and anti-cavitation performance is weakened during cavitation conditions.

19.
Nat Commun ; 11(1): 433, 2020 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31974380

RESUMEN

Ferroptosis is a newly defined form of regulated cell death characterized by the iron-dependent accumulation of lipid hydroperoxides. Erastin, the ferroptosis activator, binds to voltage-dependent anion channels VDAC2 and VDCA3, but treatment with erastin can result in the degradation of the channels. Here, the authors show that Nedd4 is induced following erastin treatment, which leads to the ubiquitination and subsequent degradation of the channels. Depletion of Nedd4 limits the protein degradation of VDAC2/3, which increases the sensitivity of cancer cells to erastin. By understanding the molecular mechanism of erastin-induced cellular resistance, we can discover how cells adapt to new molecules to maintain homeostasis. Furthermore, erastin-induced resistance mediated by FOXM1-Nedd4-VDAC2/3 negative feedback loop provides an initial framework for creating avenues to overcome the drug resistance of ferroptosis activators.


Asunto(s)
Antineoplásicos/farmacología , Melanoma/tratamiento farmacológico , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Ubiquitina-Proteína Ligasas Nedd4/metabolismo , Piperazinas/farmacología , Canal Aniónico 2 Dependiente del Voltaje/metabolismo , Canales Aniónicos Dependientes del Voltaje/metabolismo , Animales , Línea Celular Tumoral , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/fisiología , Femenino , Ferroptosis/efectos de los fármacos , Ferroptosis/fisiología , Proteína Forkhead Box M1/metabolismo , Humanos , Melanoma/metabolismo , Melanoma/patología , Ratones Desnudos , Proteínas de Transporte de Membrana Mitocondrial/genética , Ubiquitina-Proteína Ligasas Nedd4/genética , Ubiquitinación/efectos de los fármacos , Canal Aniónico 2 Dependiente del Voltaje/genética , Canales Aniónicos Dependientes del Voltaje/genética , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Nat Commun ; 10(1): 1693, 2019 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-30979895

RESUMEN

Autophagy maintains homeostasis and is induced upon stress. Yet, its mechanistic interaction with oncogenic signaling remains elusive. Here, we show that in BRAFV600E-melanoma, autophagy is induced by BRAF inhibitor (BRAFi), as part of a transcriptional program coordinating lysosome biogenesis/function, mediated by the TFEB transcription factor. TFEB is phosphorylated and thus inactivated by BRAFV600E via its downstream ERK independently of mTORC1. BRAFi disrupts TFEB phosphorylation, allowing its nuclear translocation, which is synergized by increased phosphorylation/inactivation of the ZKSCAN3 transcriptional repressor by JNK2/p38-MAPK. Blockade of BRAFi-induced transcriptional activation of autophagy-lysosomal function in melanoma xenografts causes enhanced tumor progression, EMT-transdifferentiation, metastatic dissemination, and chemoresistance, which is associated with elevated TGF-ß levels and enhanced TGF-ß signaling. Inhibition of TGF-ß signaling restores tumor differentiation and drug responsiveness in melanoma cells. Thus, the "BRAF-TFEB-autophagy-lysosome" axis represents an intrinsic regulatory pathway in BRAF-mutant melanoma, coupling BRAF signaling with TGF-ß signaling to drive tumor progression and chemoresistance.


Asunto(s)
Resistencia a Antineoplásicos , Regulación Neoplásica de la Expresión Génica , Melanoma/metabolismo , Proteínas Proto-Oncogénicas B-raf/metabolismo , Neoplasias Cutáneas/metabolismo , Animales , Autofagia , Línea Celular Tumoral , Progresión de la Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Células HEK293 , Humanos , Lisosomas/metabolismo , Melanoma/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Microscopía Confocal , Metástasis de la Neoplasia , Trasplante de Neoplasias , Oncogenes , Fosforilación , ARN Interferente Pequeño , Transducción de Señal , Neoplasias Cutáneas/patología , Fracciones Subcelulares , Factor de Crecimiento Transformador beta/metabolismo
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