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We investigate theoretically the photoelectron momentum distributions (PMDs) of the helium atom in the few-cycle nonlinear chirped laser pulse. The numerical results show that the direction of the spider-like interference structure in PMDs exhibits periodic variations with the increase of the chirp parameter. It is illustrated that the direction of the spider-like interference structure is related to the direction of the electron motion by tracking the trajectories of the electrons. We also demonstrate that the carrier-envelope phase can precisely control the opening of the ionization channel. In addition, we investigate the PMDs when a chirp-free second harmonic (SH) laser pulse is added to the chirped laser field, the numerical results show that the interference patterns can change from only spider-like interference structure to both spider-like and ring-like interference structures.
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We theoretically investigate the photoelectron momentum distribution of He atoms by numerically solving the time-dependent Schro¨dinger equation (TDSE) in few-cycle ionization gating, which is synthesized by two linearly polarized laser pulses. When applying the TDSE, we can clearly see the spider-like structures in the photoelectron momentum spectra. We also find that the spider-like structures can be isolated by changing the relative phase. The directionality of the spider-like structure is changed from right-side to left-side and the ring-like interference structure gradually appears in the photoelectron momentum spectra when increasing the relative phase. The interference patterns observed in TDSE are recaptured well by the quantum-trajectory Monte Carlo (QTMC) model. We separate the ionization time window of the tunneling electron by analyzing the ionization rate. With the help of QTMC simulation, we illustrate the change of the interference structure and its directionality in the photoelectron momentum spectra. By changing the relative phase, the forward-backward asymmetry of the momentum distribution of the emitted electrons can also be controlled. Moreover, we find that the relative contribution of the nonrescattering and the rescattering trajectories can be controlled. These properties are beneficial for the application of photoelecron holography in probing atomic and molecular structures and dynamics.
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We theoretically investigate strong-filed electron vortices in time-delayed circularly polarized laser pulses by a generalized quantum-trajectory Monte Carlo (GQTMC) model. Vortex interference patterns in photoelectron momentum distributions (PMDs) with various laser parameters can be well reproduced by the semiclassical simulation. The phase difference responsible for the interference structures is analytically identified through trajectory-based analysis and simple-man theory, which reveal the underlying mechanism of electron vortex phenomena for both co-rotating and counter-rotating component. This semiclassical analysis can also demonstrate the influences of laser intensity and wavelength on the number of arms of vortices. Furthermore, we show the influence of the Coulomb effect on the PMDs. Finally, the controlling of the ionization time intervals in the tens to hundreds of attosecond magnitude is qualitatively discussed.
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With the three-dimensional (3D) classical ensemble method, we theoretically investigate the recollision dynamics in strong-field nonsequential double ionization (NSDI) of Ar by counter-rotating two-color circularly polarized laser fields. With the analysis of the NSDI trajectories, we find that not only multiple-recollision but also single-recollision processes occur in the double ionization events. Furthermore, the multiple-recollision and single-recollision processes both undergo the recollision-induced excitation with subsequent ionization (RESI) and recollision-induced ionization (RII). The angle between the momentum and the force of the laser field at the recollision moment can affect the times of the recollision.
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With the classical ensemble method, the correlated-electron dynamics of Mg atom from a doubly excited, transition Coulomb complex in few-cycle circularly polarized (CP) laser field at low laser intensity is theoretically investigated. The low energy transfer during the recollision process indicates that the two electrons cannot release directly, but it can pass through a doubly excited state, and then escape with the ionization time difference. The numerical results show that the feature of the sequential double ionization (SDI) can be observed in the nonsequential double ionization (NSDI) process. The SDI-like results demonstrate that the intermediate state has lost any memory of its formation dynamics. The distribution of the angle between the two release directions of the two electrons also depends on the ionization time difference. Finally, the influence of e-e Coulomb repulsion is discussed.
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By solving a two-dimensional time-dependent Schrödinger equation we investigate high harmonic generation (HHG) and isolated attosecond pulse generation for the H2+ molecular ion in a circularly polarized laser pulse combined with a Terahertz (THz) field. The harmonic intensity can be greatly enhanced and a continuum spectrum can be obtained when a THz field is added. The HHG process is studied by the semi-classical three-step model and the time-frequency analysis. Our studies show that only short trajectories contribute to HHG. Furthermore, we present the temporal evolution of the probability density of electron wave packet, which perfectly shows a clear picture of the electron's two-time recombination when a THz field is added, and it is the main mechanism of HHG. By superposing the harmonics in the range of 216-249 eV, an isolated attosecond pulse with a duration of about 69 attoseconds can be generated.
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Ca-alginate-poly-l-lysine-alginate (APA-Ca) and Ba-alginate-poly-l-lysine-alginate (APA-Ba) microcapsules were prepared and their thickness and surface were examined by light microscopy and scanning electron microscopy. Specifically, light microscopy with frozen section was used to visualize and quantify the thickness of APA membrane, and monitor temporal changes in the thickness of microcapsules during a month long culture in vitro. The section graph of APA microcapsule represents the accurate measurement of layer thickness of APA-Ca with diameter 900 ± 100 and 500 ± 100 µm at 6.01 ± 1.02 and 9.54 ± 2.42 µm (p < 0.05), and layer thickness of APA-Ba with diameter 900 ± 100 and 500 ± 100 µm at 5.47 ± 0.90 and 8.21 ± 1.97 µm (p < 0.05), regardless of the alginate composition used to generate the microcapsules. The microcapsule was stable during the culture for 30 days in vitro. Field emission scanning electron microscopy with freeze drying method was used to detect the surface and thickness of dried microcapsules. From the results, the outer surface of APA-Ca and APA-Ba membrane were smooth and dense, the film thickness of the APA-Ca was about 450-690 nm, while the APA-Ba was approximately 335 nm. In vivo experiment, little significant difference was seen in the change of film thickness of microcapsules in intrapertioneal site for 30 days after transplantation (p > 0.05), except that the recovery of APA-Ba was higher than the APA-Ca microcapsules. The paper showed an easy method to prepare APA-Ca and APA-Ba, and examine their thickness and surface, which could be utilized to study other types of microcapsules.
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Alginatos/química , Bário/química , Cálcio/química , Cápsulas/química , Polilisina/análogos & derivados , Química Farmacêutica , Estabilidade de Medicamentos , Microscopia , Polilisina/química , Propriedades de SuperfícieRESUMO
INTRODUCTION: The purpose of this study was to investigate the effects and potential mechanisms of ferroptosis-related gene heat shock protein beta-1 (HSPB1) on acute myeloid leukemia (AML). METHODS: The RNA-seq and clinical data of AML samples were obtained from the Genomic Data Commons database, and the FerrDb database was used to screen the marker, drive and suppressor of ferroptosis. Besides, DESeq2 was applied for differential expression analysis on AML samples and screening for differentially expressed genes (DEGs). The screened DEGs were subjected to the intersection analysis with ferroptosis-related genes to identify the ferroptosis-related DEGs. Next, the functional pathways of ferroptosis-related DEGs were further be discussed by Gene Ontology as well as Kyoto Encyclopedia of Genes and Genomes enrichment analysis of DEGs. Additionally, lasso regression analysis was employed to determine the differential genes related to prognosis in patients with AML and the survival analysis was performed. Subsequently, quantitative real-time polymerase chain reaction and western blot assay were applied to detect the mRNA and protein expression levels of HSPB1 in normal/AML bone marrow tissues and human normal (HS-5)/AML (HL-60) bone marrow cells, respectively. Furthermore, HSPB1 was knocked down to assess the expression changes of glutathione peroxidase 4 and acyl-CoA synthetase long-chain family member 4. Ultimately, the viability and oxidative stress levels of HL-60 were analyzed by Cell Counting Kit-8 and biochemical detection. RESULTS: A total of 4986 DEGs were identified in AML samples, with 3324 up-regulated and 1662 down-regulated. The enrichment analysis illustrated that ferroptosis-related DEGs were significantly enriched in response to metal irons, oxidative stress, and other pathways. After lasso regression analysis, 17 feature genes related to the prognosis of patients with AML were obtained, with HSPB1 exhibiting a significant correlation. The reliability of our models was verified by Cox regression analysis and survival analysis of the hazard model. Furthermore, the outcomes of quantitative real-time polymerase chain reaction and western blot showed that mRNA and protein expression levels of HSPB1 were significantly increased in the AML Group and HL-60 cells. The knockdown of HSPB1 in HL-60 cells reduced the protein level of glutathione peroxidase 4, increased the protein level of acyl-CoA synthetase long-chain family member 4, decreased the cell viability, and aggravated oxidative stress. CONCLUSION: Ferroptosis-related gene HSPB1 is highly expressed in patients with AML. In addition, HSPB1 may be involved in the occurrence and development of AML by regulating oxidative stress and ferroptosis-related pathways. This study provides new clues for further understanding of AML molecular mechanisms. Also, HSPB1 is expected to be a potential therapeutic target for AML in the future.
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Background: The C-X-C motif chemokine ligand-9 (CXCL9) is related to the progression of multiple neoplasms. Yet, its biological functions in uterine corpus endometrioid carcinoma (UCEC) remain shrouded in confusion. Here, we assessed the prognostic significance and potential mechanism of CXCL9 in UCEC. Methods: Firstly, bioinformatics analysis of the public cancer database, including the Cancer Genome Atlas / the Genotype-Tissue Expression project (TCGA+ GTEx, n=552) and Gene Expression Omnibus (GEO): GSE63678 (n=7), were utilized for the CXCL9 expression-related analysis in UCEC. Then, the survival analysis of TCGA-UCEC was performed. Futher, the gene set enrichment analysis (GSEA) was carried out to reveal the potential molecular signaling pathway in UCEC associated with CXCL9 expression. Moreover, the immunohistochemistry (IHC) assay of our validation cohort (n=124) from human specimens were used to demonstrate the latent significance of CXCL9 in UCEC. Results: The bioinformatics analysis suggested that CXCL9 expression was significantly upregulated in UCEC patients; and hyper-expression of CXCL9 was related to prolonged survival. the GSEA enrichment analysis showed various immune response-related pathways, including T/NK cell, lymphocyte activation, cytokine-cytokine receptor interaction network, and chemokine signaling pathway, mediated by CXCL9. In addition, the cytotoxic molecules (IFNG, SLAMF7, JCHAIN, NKG7, GBP5, LYZ, GZMA, GZMB, and TNF3F9) and the immunosuppressive genes (including PD-L1) were positively related to the expression of CXCL9. Further, the IHC assay indicated that the CXCL9 protein expression was mainly located in intertumoral and significantly upregulated in the UCEC patients; UCEC with high intertumoral CXCL9 cell abundance harbored an improved prognosis; a higher ratio of anti-tumor immune cells (CD4+, CD8+, and CD56+ cell) and PD-L1 was found in UCEC with CXCL9 high expression. Conclusion: Overexpressed CXCL9 correlates with antitumor immunity and is predictive of a favorable prognosis in UCEC. It hinted that CXCL9 may serve as an independent prognostic biomarker or therapeutic target in UCEC patients, which augmented anti-tumor immune effects to furnish survival benefits.
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Background: Endothelial-specific molecule 1 (ESM1) dysregulation is widespread in various malignancies. However, the exact significance of ESM1 in cervical squamous cell carcinoma (CSCC) is not yet well understood. Methods: The expression of ESM1 in CSCC was probed by immunohistochemistry (IHC) assay using human specimens and validated and explored ESM1 in CSCC based on TNMplot and TCGA (The Cancer Genome Atlas Program) data repository. Further, the GSEA analysis and in vitro experiments of human CSCC cell lines, including SiHa and ME-180, were performed to investigate the masked molecular mechanisms of ESM1 in CSCC. Results: ESM1 was overexpressed in clinical CSCC tissues compared with paracancer controls, was an independent prognostic factor and was associated with poor prognosis in CSCC patients. These findings were further confirmed in the TNMplot and TCGA datasets. Furthermore, GSEA analysis revealed that the ESM1 high expression group was significantly enriched in carcinoma angiogenesis and the VEGFα signaling pathway. In addition, in vitro assays with human CSCC cell lines, including SiHa and ME-180, demonstrated that knockdown of ESM1 expression inhibited tumor cell proliferation, migration and invasion, resulting in attenuated VEGFα expression and blocked phosphorylation of VEGFR2 and ERK-1/2. Conclusion: In CSCC patients, ESM1 was considerably overexpressed. Upregulation of ESM1 is predictive of poor clinical outcomes in CSCC. Furthermore, ESM1 overexpression promoted carcinoma angiogenesis and CSCC progression through the VEGF/ERK signaling pathway. Hence, ESM1 and associated genes might be useful prognostic biomarkers or therapeutic targets for CSCC individuals.
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Waldenström macroglobulinemia (WM) rarely leads to pulmonary embolism. Due to its low incidence, the underlying pathophysiology, prognosis, and optimal treatment remain largely unexplored and uninvestigated. In this study, a patient with a double-clonal WM, a rare subtype, presented with pulmonary embolism. The patient had a small number of plasma cells without morphological abnormalities, and an effective therapeutic response was observed. Nonetheless, the clinical prognosis requires a long-term follow-up.
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Pulmonary hypertension (PH) is a progressive, pulmonary vascular disease with high morbidity and mortality. Unfortunately, the pathogenesis of PH is complex and remains unclear. Existing studies have suggested that inflammatory factors are key factors in PH. Interleukin-6 (IL-6) is a multifunctional cytokine that plays a crucial role in the regulation of the immune system. Current studies reveal that IL-6 is elevated in the serum of patients with PH and it is negatively correlated with lung function in those patients. Since IL-6 is one of the most important mediators in the pathogenesis of inflammation in PH, signaling mechanisms targeting IL-6 may become therapeutic targets for this disease. In this review, we detailed the potential role of IL-6 in accelerating PH process and the specific mechanisms and signaling pathways. We also summarized the current drugs targeting these inflammatory pathways to treat PH. We hope that this study will provide a more theoretical basis for targeted treatment in patients with PH in the future.
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Hipertensão Pulmonar , Humanos , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/terapia , Interleucina-6/metabolismo , Pulmão/patologia , Inflamação/patologia , Transdução de SinaisRESUMO
Primary cutaneous follicle center lymphoma (PCFCL) differs from follicular lymphoma in biological behavior and molecular profile and is treated as a distinct entity, according to the 5th edition of the World Health Organization classification of hematolymphoid tumors. It is an uncommon cutaneous B-cell lymphoma that is considerably rare in children and adolescents. To date, only 13 cases of individuals younger than 20 years of age have been reported in the literature. The lack of relevant clinical epidemiological data in this population has hampered the investigation of its clinical and diagnostic aspects. Here we report the case of a 17-year-old male with PCFCL, who may be the first PCFCL patient under 20 years of age reported in China. He was admitted to the hospital with a solitary nodule on his face. After complete surgical excision, the patient's facial mass was histologically identified as PCFCL. The patient's prognosis was favorable, with no recurrence at 17 months of follow-up after the surgical resection. We present a case of an adolescent PCFCL patient and systematically review the literature with a view to increase the awareness of the disease and inform the diagnosis and treatment of this age group.
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In this paper, disordered mesoporous silica loaded with ultrasmall-sized and highly dispersed CuO nanoparticles was obtained by an alkali-free strategy. Pre-prepared copper bromoacetate (CuBA) and (3-aminopropyl)triethoxysilane (APTES) were selected as reactants, which can be covalently connected with each other for the formation of functional hybrid precursors. Simultaneously, the protonated amino group with the ability to promote the hydrolysis of silane was generated, avoiding any additional catalyst. The covalent introduction of copper salt by chemical bonding promised the molecular-level dispersion of copper ions, favouring the in situ generation of ultrasmall-sized and highly dispersed CuO nanoparticles in the silica matrix. The average diameter of this obtained composited silica material is around 700 nm, and CuO nanoparticles with an average diameter of â¼3 nm were uniformly dispersed in the silica matrix. Typically, disordered mesopores were obtained under the thermolysis of organic chains in the hybrid silica matrix; the BET surface area is 77 m2 g-1 and the pore diameter is about 2.5 nm. The catalytic property was investigated and the results show that this obtained CuO@mSiO2 material has good catalytic performance in the reduction of organic dye with NaBH4 as the reducing agent.
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BACKGROUND AND PURPOSE: L. monocytogenes remain a leading cause of foodborne infection. Listeriolysin O (LLO), an indispensable virulence determinant involved in diverse pathogenic mechanisms of L. monocytogenes infection, represents a promising therapeutic target. In this study, we sought to identify an effective inhibitor of LLO pore formation and its mechanism of action in the treatment of L. monocytogenes infection. EXPERIMENTAL APPROACH: Haemolysis assays were carried out to screen an effective LLO inhibitor. The interaction between candidate and LLO was investigated using surface plasmon resonance and molecular docking. The effect of candidate on LLO-mediated cytotoxicity, barrier disruption and immune response were investigated. Finally, the in vivo effect of candidate on mice challenged with L. monocytogenes was examined. KEY RESULTS: Amentoflavone, a natural flavone present in traditional Chinese herbs, effectively inhibited LLO pore formation by engaging the residues Lys93, Asp416, Tyr469 and Lys505 in LLO. Amentoflavone dose-dependently reduced L. monocytogenes-induced cell injury in an LLO-dependent manner. In the Caco-2 monolayer model, amentoflavone maintained the integrity of the epithelial barrier exposed to LLO. Amentoflavone inhibited the inflammatory response evoked by L. monocytogenes in an LLO-dependent manner, and inhibition was attributed to ability to block perforation-associated K+ efflux and Ca2+ influx. In the mouse infection model, amentoflavone treatment significantly reduced bacterial burden and pathological lesions in target organs, with a significant increase in survival rate. CONCLUSIONS AND IMPLICATIONS: Amentoflavone reduced the pathogenicity of L. monocytogenes by specifically inhibiting LLO pore formation, and this may represent a potential treatment for L. monocytogenes infection.
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Listeria monocytogenes , Listeriose , Animais , Toxinas Bacterianas , Biflavonoides , Células CACO-2 , Modelos Animais de Doenças , Proteínas de Choque Térmico , Proteínas Hemolisinas/farmacologia , Proteínas Hemolisinas/uso terapêutico , Humanos , Listeriose/tratamento farmacológico , Listeriose/microbiologia , Camundongos , Simulação de Acoplamento Molecular , VirulênciaRESUMO
Aloe-emodin (1,8-dihydroxy-3-hydroxymethyl-anthraquinone), derived from some Chinese edible medicinal herbs, exerts a potential anticancer activity on various cancer cells, making it a drug candidate for cancer therapy. Yet, the role of aloe-emodin in pyroptosis, a new type of cell death, is uncharacterized. In this study, we explored the molecular mechanisms of aloe-emodin-triggered pyroptosis. Aloe-emodin inhibited proliferation and migration and triggered caspase-dependent cell death of HeLa cells in a dose-dependent manner. Aloe-emodin caused mitochondrial dysfunction and induced pyroptosis by activating the caspase-9/3/GSDME axis. Transcriptional analysis showed extensive changes in gene expressions in cellular pathways, including MAPK, p53, and PI3K-Akt pathways when treated with aloe-emodin. This study not only identified a novel role of aloe-emodin in pyroptotic cell death, but also performed a systematical genome-wide analysis of cellular pathways responding to aloe-emodin, providing a theoretical basis for applying anthraquinone derivatives in the treatment of GSDME-expressing cancers.
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BACKGROUND: Neuroinflammation-mediated microglia polarization is a major process in various central nervous system (CNS) diseases. Endoplasmic reticulum (ER) stress contributes to the inflammatory signals as well as to microglia polarization in lipopolysaccharide (LPS) induced neuroinflammation. Ascorbic acid 6-palmitate (L-AP) has been broadly used as a dietary antioxidant in foods and demonstrated a strong inhibitory effect on 5-LOX; however, the specific anti-inflammation mechanisms remain unclear. In this study, we investigated the effects and possible mechanisms of L-AP on LPS-induced neuroinflammation in BV-2 cells. METHODS: Immortalized murine microglia cell line BV-2 cells were employed to assess the effect of L-AP to modulate microglia M1/M2 polarization in vivo, and the molecular mechanism was evaluated by qRT-PCR and Western blotting analysis. Molecular docking was used to predict the binding activity of L-AP with protein kinase R-like ER kinase (PERK). RESULTS: L-AP at 62.5 µM significantly modulated LPS-induced microglia M1/M2 polarization (increases of interleukin (IL)-10 and arginase-1 (Arg-1) transcriptions) independent of cell growth. Besides, L-AP at 62.5 µM significantly down-regulated glucose-regulated protein 78 (GRP78) and CCAAT/enhancer-binding homologous protein (CHOP) mRNA levels. Similar data were shown in the tunicamycin (TM) induced ER stress cells model. Moreover, the protective effect of L-AP on TM-induced microglia M1/M2 polarization was similar to that of 4-phenyl butyric acid (4-PBA), the ER stress inhibitor. Molecular docking results indicated L-AP might directly bind with PERK, with a binding affinity of -7.7 kcal/mol. A further study unveiled that L-AP notably inhibited LPS-induced PERK/ eukaryotic initiation factor 2α (elf2α) activation. CONCLUSION: Together, this study revealed that L-AP possessed its effect on the reconstruction of microglia M1/M2 polarization balance in LPS-stimulated BV-2 cells via modulating PERK/elF2α mediated ER stress.
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Lipopolissacarídeos , Microglia , Camundongos , Animais , Lipopolissacarídeos/farmacologia , Estresse do Retículo Endoplasmático , Simulação de Acoplamento Molecular , Ácido Ascórbico/metabolismo , Ácido Ascórbico/farmacologia , Palmitatos/metabolismo , Palmitatos/farmacologiaRESUMO
The mesencephalic astrocyte-derived neurotrophic factor (MANF), also named as arginine-rich protein (ARP) or arginine-rich mutated in early-stage tumors (ARMET), is a novel evolutionary conserved protein related to unfolded protein response. Growing evidence suggests that MANF critically involves in many ER stress-related diseases with a protective effect. Here, we review the function of MANF based on its structure in neurological and metabolic disorders and summarize its potential applications in disease diagnosis and therapies.
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Estresse do Retículo Endoplasmático , Doenças Metabólicas/patologia , Fatores de Crescimento Neural/metabolismo , Doenças do Sistema Nervoso/patologia , Resposta a Proteínas não Dobradas , Humanos , Doenças Metabólicas/metabolismo , Doenças Metabólicas/terapia , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/terapiaRESUMO
The histone lysine demethylase KDM5 family is implicated in normal development and stem cell maintenance by epigenetic modulation of histone methylation status. Deregulation of the KDM5 family has been reported in various types of cancers, including hematological malignancies. However, their transcriptional regulatory roles in the context of leukemia remain unclear. Here, we find that KDM5B is strongly expressed in normal CD34+ hematopoietic stem/progenitor cells and chronic myeloid leukemia (CML) cells. Knockdown of KDM5B in K562 CML cells reduced leukemia colony-forming potential. Transcriptome profiling of KDM5B knockdown K562 cells revealed the deregulation of genes involved in myeloid differentiation and Toll-like receptor signaling. Through the integration of transcriptome and ChIP-seq profiling data, we show that KDM5B is enriched at the binding sites of the GATA and AP-1 transcription factor families, suggesting their collaborations in the regulation of transcription. Even though the binding of KDM5B substantially overlapped with H3K4me1 or H3K4me3 mark at gene promoters, only a small subset of the KDM5B targets showed differential expression in association with the histone demethylation activity. By characterizing the interacting proteins in K562 cells, we discovered that KDM5B recruits protein complexes involved in the mRNA processing machinery, implying an alternative epigenetic action mediated by KDM5B in gene regulation. Our study highlights the oncogenic functions of KDM5B in CML cells and suggests that KDM5B is vital to the transcriptional regulation via multiple epigenetic mechanisms.
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Epigênese Genética , Regulação Leucêmica da Expressão Gênica , Células-Tronco Hematopoéticas/enzimologia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Diferenciação Celular , Perfilação da Expressão Gênica , Células-Tronco Hematopoéticas/patologia , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Repressoras/genéticaRESUMO
BACKGROUND AND PURPOSE: Autophagy is a critical cellular catabolic process in cell homoeostasis and brain function. Recent studies indicate that receptor for activated C kinase 1 (RACK1) is involved in autophagosome formation in Drosophila and mice, and that it plays an essential role in morphine-associated memory. However, the exact mechanism of the role of RACK1 in morphine-induced autophagy is not fully understood. EXPERIMENTAL APPROACH: SH-SY5Y cells were cultured and morphine, rapamycin, 3-methyladenine and RACK1 siRNA were used to evaluate the regulation of RACK1 protein in autophagy. Western blotting and immunofluorescence were used to assess protein expression. KEY RESULTS: Activation of autophagy (i.e. autophagosome accumulation and an increase in the LC3-II/LC3-I ratio) induced by morphine contributes to the maintenance of conditioned place preference (CPP) memory in mice. Moreover, morphine treatment significantly increased Beclin-1 expression and decreased the p-mTOR/mTOR and SQSTM1/p62 levels, whereas knockdown of RACK1 prevented morphine-induced autophagy in vitro. Furthermore, we found that in the mouse hippocampus, knockdown of RACK1 also markedly suppressed morphine-induced autophagy (decreased LC3-II/LC3-I ratio and increased p-mTOR/mTOR ratio). Importantly, morphine-induced autophagy in a RACK1-dependent manner. Conversely, morphine-induced RACK1 upregulation in vitro is partially inhibited by autophagy feedback. CONCLUSIONS AND IMPLICATIONS: Our findings revealed a critical role for RACK1-dependent autophagy in morphine-promoted maintenance of CPP memory in mice and supported the notion that control of RACK1-dependent autophagic pathways may become an important target for novel therapeutics for morphine-associated memory.