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1.
Cancer Sci ; 114(9): 3523-3536, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37350063

RESUMO

Nuclear factor erythroid 2-like 3 (NFE2L3) is a member of the cap 'n' collar basic-region leucine zipper (CNC-bZIP) transcription factor family that plays a vital role in modulating oxidation-reduction steady-state and proteolysis. Accumulating evidence suggests that NFE2L3 participates in cancer development; however, little is known about the mechanism by which NFE2L3 regulates hepatocellular carcinoma (HCC) cell growth. Here, we confirmed that NFE2L3 promotes HCC cell proliferation by acting as a transcription factor, which directly induces the expression of proteasome and interferon-stimulated gene 15 (ISG15) to enhance the proteasome-dependent degradation of ISGylated p53. Post-translational ISGylation abated the stability of p53 and facilitated HCC cell growth. In summary, we uncovered the pivotal role of NFE2L3 in promoting HCC cell proliferation during proteostasis. This finding may provide a new target for the clinical treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica
2.
Anal Chem ; 95(14): 5920-5926, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36989391

RESUMO

In this work, we have found for the first time that the fluorescence of rhodamine B (RhB) would be dramatically reduced after it bound to hemin/G-quadruplex and reacted with •OH. Based on this finding, we have designed a colorimetric and fluorescent dual-mode sensing platform for visual detection of hydrogen sulfide (H2S). The constructed sensor is based on the formation of dsDNA and the G-quadruplex structure by the cytosine-Ag+-cytosine mismatch, causing H2O2-mediated catalysis to oxidize ABTS or RhB to induce a colorimetric or fluorescent change. In the presence of H2S, the solution color for colorimetric and fluorescent assays would change from dark green to pink and from green (fluorescence off) to bright yellow (fluorescence on), respectively. This dual-mode assay showed high selectivity toward H2S over other interference materials with a low measurable detection limit value (below than 2.5 µM), and it has been successfully applied to H2S visual detection in real samples. Moreover, the dual-mode sensing strategy presented an excellent reutilization character both in colorimetric and fluorescent assays. This method was employed as a label-free, simple, fast, and equipment-free platform for H2S detection with high selectivity and reusability. This work realized naked-eye detection both in colorimetric and fluorescent analysis at a lower concentration of H2S, demonstrating a promising strategy for on-site visual detection of H2S.


Assuntos
Sulfeto de Hidrogênio , Sulfeto de Hidrogênio/análise , Colorimetria/métodos , Peróxido de Hidrogênio/química , Corantes Fluorescentes/química , Hemina
3.
Phys Chem Chem Phys ; 25(14): 9772-9778, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36946196

RESUMO

Nanocluster photoluminescence (PL) has important practical applications and its rationalization is therefore of significant interest. Here, we report the synthesis, structure determination and photoluminescence of Au10Ag17(TPP)10(SR)6Cl5 (TPP = triphenylphosphine, SR = 3, 5-bis(trifluoromethyl)thiophenol, denoted as Au10Ag17). Au10Ag17 exhibited a low photoluminescence quantum yield (PLQY) of 2.8%, which could be increased 15-fold by removing the two terminal silver atoms to give AgxAu25-x(SR)5(TPP)10Cl22+ (x = 11-13, SR = 2-phenylethylmercaptan, abbrev. Au12Ag13). The discovery of such a PL switch constitutes an interesting opportunity to further understand the origin of fluorescence in nanoclusters.

4.
J Cardiovasc Pharmacol ; 79(5): 730-738, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121714

RESUMO

ABSTRACT: Hyperhomocysteinemia is an independent risk factor for atherosclerosis. It is known that macrophage autophagy plays a protective role in atherosclerosis and that hyperhomocysteinemia is strongly linked to autophagy. Therefore, it is of great significance to study the molecular mechanisms underlying the effect of homocysteine (Hcy) on macrophage autophagy. This study aimed to investigate the effects of Hcy on autophagy in a human acute monocytic leukemia cell line (THP-1). The Hcy-treated THP-1 cells exhibited increased levels of the autophagy substrate SQSTM1 (p62) and decreased levels of the autophagy markers LC3 II/I and Beclin-1, indicating a decrease in autophagy in vitro. Furthermore, Western blotting showed that Hcy significantly increased the levels of p-mTOR and nuclear TFEB and decreased the levels of p-AMPK and cytoplasmic TFEB. These data suggest that Hcy inhibits autophagosome formation in human THP-1 macrophages through the AMPK-mTOR-TFEB signaling pathway. Our findings provide new insights into the mechanisms of atherosclerotic diseases caused by Hcy.


Assuntos
Aterosclerose , Hiper-Homocisteinemia , Proteínas Quinases Ativadas por AMP/metabolismo , Aterosclerose/metabolismo , Autofagia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/farmacologia , Criança , Homocisteína/toxicidade , Humanos , Macrófagos , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
5.
Biochem Biophys Res Commun ; 541: 95-101, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33493685

RESUMO

The tumor microenvironment is a complex microenvironment that combines the biochemical and biophysical factors. When the cells are exposed to the microenvironment, the direct biophysical factor is the matrix hardness. As an auxiliary indicator of clinical disease diagnosis, it is still not clear how the matrix hardness induces cell malignant changes and the regulation mechanisms. In this study, we identified that hard matrix significantly promoted cancer cell migratory behaviors. Cell shape was closely associated with cancer cell malignancy, the high malignant cells were associated with high ratios of length/width and low circularity. F-actin networks were also linked with extracellular matrix, it was not regularly distributed when cells were in non-malignant tumor phases or under F-actin inhibition. F-actin might play the key role that transmitted the signal from extracellular matrix to the intracellular organelles. Further study confirmed that active YAP was translocated to nucleus on hard matrix. Cells on hard matrix with cytochalasin D reversed the cancer cell malignancy, meanwhile F-actin re-distributed to the membrane and YAP nucleus translocations were hindered. This work confirmed that F-actin and YAP were upstream-downstream cascade for the cellular and nucleus outside-in signal transductions. The above results demonstrated that hard matrix promoted breast cancer cell malignant behaviors through F-actin network and YAP activation. These results not only described the signal transductions from extracellular to intracellular that was initiated by the biophysical tumor microenvironment, but provided clinical intervention ideas for cancer treatments.


Assuntos
Neoplasias da Mama/patologia , Movimento Celular , Forma Celular , Citoesqueleto/metabolismo , Progressão da Doença , Matriz Extracelular/metabolismo , Dureza , Actinas/metabolismo , Transporte Ativo do Núcleo Celular , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Citocalasina D/farmacologia , Humanos , Transdução de Sinais , Fatores de Transcrição/metabolismo , Microambiente Tumoral , Proteínas de Sinalização YAP
6.
Toxicol Appl Pharmacol ; 420: 115523, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33838154

RESUMO

Metformin, as the first-line drug for the treatment of type 2 diabetes mellitus, has been shown to possess a capability to activate or inhibit the production of reactive oxygen species (ROS) in different ways. However, the detailed mechanisms of the opposite effect are poorly understood. Here we provide evidence that metformin induces accumulation of ROS by inhibiting the expression of a core antioxidant transcription factor nuclear factor erythroid 2 like 1 (NFE2L1/Nrf1) in human hepatocellular carcinoma HepG2 cells. In the present study, we originally found that the increased ROS induced by metformin was blunted in NFE2L1 knockdown cell line. Furtherly by examining the effects of metformin on endogenous and exogenous NFE2L1, we also found metformin could not only inhibit the transcription of NFE2L1 gene, but also promote the degradation of NFE2L1 protein at the post-transcriptional level, whereas this effect can be reversed by high glucose. The inhibitory effect of metformin on NFE2L1 was investigated to occur through the N-terminal domain (NTD) of NFE2L1 protein, and its downregulation by metformin was in an AMP-activated protein kinase (AMPK)-independent manner. But the activation of AMPK signaling pathway by metformin in NFE2L1 knockdown HepG2 cells is reversed, indicating that NFE2L1 may be an important regulator of AMPK signal. Altogether, this work provides a better understanding of the relationship between metformin and oxidative stress, and hence contributes to translational study of metformin through its hypoglycemic and tumor suppressive effects.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Metformina/farmacologia , Fator 1 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fator 1 Relacionado a NF-E2/genética , Transdução de Sinais
7.
Nanoscale ; 16(18): 9047-9054, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38634772

RESUMO

Photothermal conversion has garnered significant attention due to its potential for efficient energy conversion and application in targeted therapies. However, controlling photothermal properties at the atomic level remains a challenge in current materials synthesis. In this study, we report the synthesis and structural determination of a phosphine and mercaptan co-protected Au5Ag12(SR)9(dppf)4 (Au5Ag12) nanocluster with an extremely low quantum yield (∼0%). For comparative purposes, we synthesized three alloy nanoclusters of similar size. Notably, Au5Ag12 demonstrates a remarkably superior photothermal conversion performance, significantly outperforming the other clusters. We investigated this variance from both absorption and emission perspectives. This research not only opens new avenues for the application of clusters with extremely low quantum yields, but also provides experimental evidence for understanding the photothermal conversion properties of cluster materials at the atomic level.

8.
Chem Commun (Camb) ; 60(23): 3162-3165, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38407303

RESUMO

Advancing catalyst design requires meticulous control of nanocatalyst selectivity at the atomic level. Here, we synthesized two Pd1Ag14 nanoclusters: Pd1Ag14(PPh3)8(SPh(CF3)2)6 and Pd1Ag14(P(Ph-p-OMe)3)7(SPh)6, each with well-defined structures. Notably, in Pd1Ag14(P(Ph-p-OMe)3)7(SPh)6, the detachment of a phosphine ligand from the top silver atom facilitates the exposure of singular active sites. This exposure significantly enhances its selectivity for the electrocatalytic reduction of CO2 to CO, achieving a Faraday efficiency of 83.3% at -1.3 V, markedly surpassing the 28.1% performance at -1.2 V of Pd1Ag14(PPh3)8(SPh(CF3)2)6. This work underscores the impact of atomic-level structural manipulation on enhancing nanocatalyst performance.

9.
Pest Manag Sci ; 80(10): 5322-5333, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38895912

RESUMO

The assessment of residue, absorption, conduction, and degradation of agricultural organosilicon surfactants in the environment is hindered by the lack of information on active ingredients and corresponding quantitative standards for organosilicon spray adjuvants. The spray adjuvant 'Jiexiaoli,' a primary organosilicon spray agent in China, was identified as hydroxy (polyethylene) propyl-heptamethyl trisiloxane (TSS-H) with 3-15 ethoxy (EO) groups. Purification of TSS-H was achieved through semi-preparative separation using high-performance liquid chromatography (HPLC), resulting in TSS-H purity exceeding 96%. An accurate residual detection method for nine oligomers (4-12 EO) of TSS-H in rice roots, stems, leaves, and culture solution samples was developed using HPLC tandem high-resolution mass spectrometry (HPLC-HRMS). Recoveries for nine oligomers of TSS-H in the four matrices ranged from 80.22% to 104.01%. Foliar application experiments demonstrated that TSS-H did not transfer from the upper to the lower parts of the rice plant. The half-lives of each oligomer (4-12 EO) in leaves were less than 3.21 days. Root application experiments revealed a root concentration factor (RCF) ranging from 0.20 to 0.56, a biological enrichment factor (BCF) ranging from 0.36 to 0.68, a transpiration factor (TSCF) ranging from 0.069 to 0.086, and a transport factor (TF) ranging from 0.08 to 0.43. These results indicated that TSS-H could be absorbed by rice roots and conducted to the above-ground parts of rice plants. This study fills the data gap in the environmental risk and food safety assessment of agricultural silicone spray adjuvants. © 2024 Society of Chemical Industry.


Assuntos
Oryza , Oryza/metabolismo , Compostos de Organossilício/química , Compostos de Organossilício/metabolismo , Cromatografia Líquida de Alta Pressão , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/química , Tensoativos/química , Tensoativos/metabolismo , Transporte Biológico , China
10.
Nanoscale Adv ; 5(12): 3287-3292, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37325530

RESUMO

Atomically precise metal nanoclusters (NCs) have emerged as a new class of ultrasmall nanoparticles with both free valence electrons and precise structures (from the metal core to the organic ligand shell) and provide great opportunities to understand the relationship between their structures and properties, such as electrocatalytic CO2 reduction reaction (eCO2RR) performance, at the atomic level. Herein, we report the synthesis and the overall structure of the phosphine and iodine co-protected Au4(PPh3)4I2 (Au4) NC, which is the smallest multinuclear Au superatom with two free e- reported so far. Single-crystal X-ray diffraction reveals a tetrahedral Au4 core stabilized by four phosphines and two iodides. Interestingly, the Au4 NC exhibits much higher catalytic selectivity for CO (FECO: > 60%) at more positive potentials (from -0.6 to -0.7 V vs. RHE) than Au11(PPh3)7I3 (FECO: < 60%), a larger 8 e- superatom, and Au(i)PPh3Cl complex; whereas the hydrogen evolution reaction (HER) dominates the electrocatalysis when the potential becomes more negative (FEH2 of Au4 = 85.8% at -1.2 V vs. RHE). Structural and electronic analyses reveal that the Au4 tetrahedron becomes unstable at more negative reduction potentials, resulting in decomposition and aggregation, and consequently the decay in catalytic performance of Au based catalysts towards the eCO2RR.

11.
Cell Death Dis ; 13(5): 501, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614059

RESUMO

The antioxidant transcription factor NFE2L1 (also called Nrf1) acts as a core regulator of redox signaling and metabolism homeostasis, and thus, its dysfunction results in multiple systemic metabolic diseases. However, the molecular mechanism(s) by which NFE2L1 regulates glycose and lipid metabolism remains elusive. Here, we found that loss of NFE2L1 in human HepG2 cells led to a lethal phenotype upon glucose deprivation and NFE2L1 deficiency could affect the uptake of glucose. Further experiments revealed that glycosylation of NFE2L1 enabled it to sense the energy state. These results indicated that NFE2L1 can serve as a dual sensor and regulator of glucose homeostasis. The transcriptome, metabolome, and seahorse data further revealed that disruption of NFE2L1 could reprogram glucose metabolism to aggravate the Warburg effect in NFE2L1-silenced hepatoma cells, concomitant with mitochondrial damage. Co-expression and Co-immunoprecipitation experiments demonstrated that NFE2L1 could directly interact and inhibit AMPK. Collectively, NFE2L1 functioned as an energy sensor and negatively regulated AMPK signaling through directly interacting with AMPK. The novel NFE2L1/AMPK signaling pathway delineate the mechanism underlying of NFE2L1-related metabolic diseases and highlight the crosstalk between redox homeostasis and metabolism homeostasis.


Assuntos
Proteínas Quinases Ativadas por AMP , Fator 1 Relacionado a NF-E2 , Proteínas Quinases Ativadas por AMP/metabolismo , Metabolismo Energético , Glucose , Homeostase , Fator 1 Relacionado a NF-E2/metabolismo , Transdução de Sinais
12.
Stem Cell Reports ; 16(8): 1894-1905, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34329593

RESUMO

During development, cells respond rapidly to intra- and intercellular signals, which induce signaling cascades regulating the activity of transcription factors at the transcriptional and/or post-translational level. The transcription factor ISL1 plays a key role in second heart field development and cardiac differentiation, and its mRNA levels are tightly regulated during cardiogenesis. Here, we show that a BMP-p38 MAPK signaling axis controls ISL1 protein function at the post-translational level. BMP-mediated activation of p38 MAPK leads to ISL1 phosphorylation at S269 by p38, which prevents ISL1 degradation and ensures its transcriptional activity during cardiogenesis. Interfering with p38 MAPK signaling leads to the degradation of ISL1 by the proteasome, resulting in defects in cardiomyocyte differentiation and impaired zebrafish and mouse heart morphogenesis and function. Given the critical role of the tight control of ISL1 activity during cardiac lineage diversification, modulation of BMP4-p38 MAPK signaling could direct differentiation into specific cardiac cell subpopulations.


Assuntos
Proteína Morfogenética Óssea 4/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Miocárdio/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Peixe-Zebra/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Animais Geneticamente Modificados , Diferenciação Celular/genética , Regulação da Expressão Gênica no Desenvolvimento , Coração/embriologia , Proteínas com Homeodomínio LIM/genética , Camundongos , Camundongos Knockout , Miocárdio/citologia , Células NIH 3T3 , Organogênese/genética , Estabilidade Proteica , Células-Tronco/metabolismo , Fatores de Transcrição/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética
13.
Front Oncol ; 11: 707032, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34268128

RESUMO

Nrf1 and Nrf2, as two principal CNC-bZIP transcription factors, regulate similar but different targets involved in a variety of biological functions for maintaining cell homeostasis and organ integrity. Of note, the unique topobiological behavior of Nrf1 makes its functions more complicated than Nrf2, because it is allowed for alternatively transcribing and selectively splicing to yield multiple isoforms (e.g., TCF11, Nrf1α). In order to gain a better understanding of their similarities and differences in distinct regulatory profiles, all four distinct cell models for stably expressing TCF11, TCF11ΔN , Nrf1α or Nrf2 have been herein established by an Flp-In™ T-REx™-293 system and then identified by transcriptomic sequencing. Further analysis revealed that Nrf1α and TCF11 have similar yet different regulatory profiles, although both contribute basically to positive regulation of their co-targets, which are disparate from those regulated by Nrf2. Such disparity in those gene regulations by Nrf1 and Nrf2 was further corroborated by scrutinizing comprehensive functional annotation of their specific and/or common target genes. Conversely, the mutant TCF11ΔN, resulting from a deletion of the N-terminal amino acids 2-156 from TCF11, resembles Nrf2 with the largely consistent structure and function. Interestingly, our further experimental evidence demonstrates that TCF11 acts as a potent tumor-repressor relative to Nrf1α, albeit both isoforms possess a congruous capability to prevent malignant growth of tumor and upregulate those genes critical for improving the survival of patients with hepatocellular carcinoma.

14.
Cell Death Dis ; 12(2): 201, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608495

RESUMO

Because of the lack of sensitivity to radiotherapy and chemotherapy, therapeutic options for renal clear cell carcinoma (KIRC) are scarce. Long noncoding RNAs (lncRNAs) play crucial roles in the progression of cancer. However, their functional roles and upstream mechanisms in KIRC remain largely unknown. Exploring the functions of potential essential lncRNAs may lead to the discovery of novel targets for the diagnosis and treatment of KIRC. Here, according to the integrated analysis of RNA sequencing and survival data in TCGA-KIRC datasets, cyclin-dependent kinase inhibitor 2B antisense lncRNA (CDKN2B-AS1) was discovered to be the most upregulated among the 14 lncRNAs that were significantly overexpressed in KIRC and related to shorter survival. Functionally, CDKN2B-AS1 depletion suppressed cell proliferation, migration, and invasion both in vitro and in vivo. Mechanistically, CDKN2B-AS1 exerted its oncogenic activity by recruiting the CREB-binding protein and SET and MYND domain-containing 3 epigenetic-modifying complex to the promoter region of Ndc80 kinetochore complex component (NUF2), where it epigenetically activated NUF2 transcription by augmenting local H3K27ac and H3K4me3 modifications. Moreover, we also showed that CDKN2B-AS1 interacted with and was stabilized by insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3), an oncofetal protein showing increased levels in KIRC. The Kaplan-Meier method and receiver operating curve analysis revealed that patients whose IGF2BP3, CDKN2B-AS1 and NUF2 are all elevated showed the shortest survival time, and the combined panel (containing IGF2BP3, CDKN2B-AS1, and NUF2) possessed the highest accuracy in discriminating high-risk from low-risk KIRC patients. Thus, we conclude that the stabilization of CDKN2B-AS1 by IGF2BP3 drives the malignancy of KIRC through epigenetically activating NUF2 transcription and that the IGF2BP3/CDKN2B-AS1/NUF2 axis may be an ideal prognostic and diagnostic biomarker and therapeutic target for KIRC.


Assuntos
Carcinoma de Células Renais/genética , Proteínas de Ciclo Celular/genética , Epigênese Genética , Neoplasias Renais/genética , Estabilidade de RNA , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética , Ativação Transcricional , Animais , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Metilação de DNA , Bases de Dados Genéticas , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Carga Tumoral
15.
J Cancer ; 11(23): 6939-6949, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123284

RESUMO

Objective: NFE2L3 is a member of the cap 'n' collar basic-region leucine zipper family. NFE2L3 has turned out to be associated with oxidative stress, but the relevance of NFE2L3 in hepatocellular carcinoma (HCC) has remained elusive. This study aimed to investigate the role of NFE2L3 in HCC and explore underlying mechanisms. Methods: Quantitative real-time PCR, western blot and immunohistochemistry were used to detect the mRNA and protein expression of NFE2L3, the expression of epithelial-mesenchymal transition (EMT) markers and Wnt/ß-catenin signaling pathway-related proteins. In loss-function experiments, HepG2 cells were transfected with lentiviral vector containing NFE2L3 short hairpin RNA or scramble control. Cell proliferation and migration were measured by Cell Counting Kit-8, Colony formation, EdU incorporation and Transwell assays respectively. Flow cytometry was used to analyze cell cycle and apoptosis. HepG2 cells were subcutaneously injected into nude mice and tumor size was measured once every other day. Results: The results revealed that high expression of NFE2L3 was positively associated with malignant behavior and EMT in HCC. Knockdown of NFE2L3 inhibited cell proliferation and migration, led to cell cycle G0/G1 arrest and induction of cell apoptosis, increased expression of E-cadherin and decreased expression of N­cadherin, Vimentin, MMP2, CDK2 and PCNA. In addition, tumor growth was inhibited by silencing of NFE2L3 in vivo. Expression of ß-catenin and Wnt target genes cyclin D1 and TCF4 was reduced in HepG2-shNFE2L3 cells. Conclusions: NFE2L3 promotes cell proliferation, metastasis, and induces EMT of hepatocellular carcinoma (HepG2) cells via activation of Wnt/ß-catenin pathway.

16.
Oxid Med Cell Longev ; 2020: 5138539, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32273945

RESUMO

Our previous work revealed that Nrf1α exerts a tumor-repressing effect because its genomic loss (to yield Nrf1α-/- ) results in oncogenic activation of Nrf2 and target genes. Interestingly, ß-catenin is concurrently activated by loss of Nrf1α in a way similar to ß-catenin-driven liver tumor. However, a presumable relationship between Nrf1 and ß-catenin is not yet established. Here, we demonstrate that Nrf1 enhanced ubiquitination of ß-catenin for targeting proteasomal degradation. Conversely, knockdown of Nrf1 by its short hairpin RNA (shNrf1) caused accumulation of ß-catenin so as to translocate the nucleus, allowing activation of a subset of Wnt/ß-catenin signaling responsive genes, which leads to the epithelial-mesenchymal transition (EMT) and related cellular processes. Such silencing of Nrf1 resulted in malgrowth of human hepatocellular carcinoma, along with malignant invasion and metastasis to the lung and liver in xenograft model mice. Further transcriptomic sequencing unraveled significant differences in the expression of both Wnt/ß-catenin-dependent and Wnt/ß-catenin-independent responsive genes implicated in the cell process, shape, and behavior of the shNrf1-expressing tumor. Notably, we identified that ß-catenin is not a target gene of Nrf1, but this CNC-bZIP factor contributes to differential or opposing expression of other critical genes, such as CDH1, Wnt5A, Wnt11A, FZD10, LEF1, TCF4, SMAD4, MMP9, PTEN, PI3K, JUN, and p53, each of which depends on the positioning of distinct cis-regulatory sequences (e.g., ARE and/or AP-1 binding sites) in the gene promoter contexts. In addition, altered expression profiles of some Wnt/ß-catenin signaling proteins were context dependent, as accompanied by decreased abundances of Nrf1 in the clinic human hepatomas with distinct differentiation. Together, these results corroborate the rationale that Nrf1 acts as a bona fide dominant tumor repressor, by its intrinsic inhibition of Wnt/ß-catenin signaling and relevant independent networks in cancer development and malignant progression.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Fator 1 Nuclear Respiratório/metabolismo , Via de Sinalização Wnt/genética , beta Catenina/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Transfecção
17.
J Cancer ; 10(26): 6666-6672, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31777595

RESUMO

Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR)-sensitive mutations benefit from epidermal growth factor receptor tyrosine kinase inhibitors (EGFR- TKIs). However, drug resistance is a major cause of therapeutic failure. This study examined whether saikosaponin-d (SSD) enhances the anti-tumor effect of gefitinib in NSCLC cells. Cell Counting Kit-8 (CCK-8) was used to determine cell viability. Cell apoptosis was examined by flow cytometry. Signal transducer and activator of transcription (STAT3), phosphor-STAT3 (P-STAT3), and B-cell lymphoma 2 (Bcl-2) were detected by Western blot. An HCC827/GR tumor model was established to observe the effect of combination therapy in vivo. The combination of SSD with gefitinib had an enhanced inhibitory effect by reducing cell viability and inducing cells apoptosis in NSCLC cells. Furthermore, SSD decreased and increased the expression of P-STAT3 and Bcl-2, respectively. Down-regulated STAT3 promoted the sensitivity of lung cancer cells to gefitinib. The results of animal experiments also showed that SSD enhanced the anti-tumor effect of gefitinib. These results indicated that the combination of SSD with gefitinib had an increased antitumor effect in NSCLC cells and that the molecular mechanisms were associated with the inhibition of STAT3/Bcl-2 signaling pathway. Our findings suggest a promising approach for the treatment of NSCLC patients with EGFR-TKI resistance.

18.
Cell Res ; 29(6): 486-501, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31024170

RESUMO

Generation of widely differing and specialized cell types from a single totipotent zygote involves large-scale transcriptional changes and chromatin reorganization. Pioneer transcription factors play key roles in programming the epigenome and facilitating recruitment of additional regulatory factors during successive cell lineage specification and differentiation steps. Here we show that Isl1 acts as a pioneer factor driving cardiomyocyte lineage commitment by shaping the chromatin landscape of cardiac progenitor cells. Using an Isl1 hypomorphic mouse line which shows congenital heart defects, genome-wide profiling of Isl1 binding together with RNA- and ATAC-sequencing of cardiac progenitor cells and their derivatives, we uncover a regulatory network downstream of Isl1 that orchestrates cardiogenesis. Mechanistically, we show that Isl1 binds to compacted chromatin and works in concert with the Brg1-Baf60c-based SWI/SNF complex to promote permissive cardiac lineage-specific alterations in the chromatin landscape not only of genes with critical functions in cardiac progenitor cells, but also of cardiomyocyte structural genes that are highly expressed when Isl1 itself is no longer present. Thus, the Isl1/Brg1-Baf60c complex plays a crucial role in orchestrating proper cardiogenesis and in establishing epigenetic memory of cardiomyocyte fate commitment.


Assuntos
Epigênese Genética/genética , Proteínas com Homeodomínio LIM/genética , Proteínas com Homeodomínio LIM/metabolismo , Miócitos Cardíacos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Células HEK293 , Humanos , Proteínas com Homeodomínio LIM/deficiência , Imageamento por Ressonância Magnética , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fatores de Transcrição/deficiência
19.
Life Sci ; 209: 267-273, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-30107167

RESUMO

OBJECTIVE: Wnt/ß­catenin signaling pathway plays important role in colorectal cancer (CRC) and acts as a potential therapeutic target. Pimozide is a FDA-approved clinical drug used to treat psychotic diseases and it has shown anticancer effect in some tumors partially via inhibition of Wnt/ß­catenin signaling pathway. This study aimed to investigate whether pimozide exerts anticancer effect on CRC and explore underlying mechanism. METHODS AND RESULTS: Pimozide was administrated to treat HCT116 and SW480 cells. Quantitative real-time polymerase chain reaction and western blot were used to detect the expression of epithelial-to-mesenchymal transition markers and Wnt/ß­catenin signaling pathway-related proteins. Cell proliferation and migration were measured by Cell Counting Kit-8 and Transwell assays respectively. HCT116 and SW480 cells were subcutaneously injected into nude mice and when the volume of tumor grown measureable (approximately 100 mm3) animals were treated with vehicle saline or pimozide at a dose of 25 mg/kg·d by oral gavage and then tumor size was measured at 7, 14, 21 and 28 days post treatment. Pimozide dose-dependently inhibited cell proliferation and migration in both HCT116 and SW480 cells, increased expression of E-cadherin and decreased expression of N­cadherin, vimentin and Snail. In addition, tumor growth was inhibited by pimozide in both HCT116 and SW480 xenografts in vivo. Expression of ß­catenin and Wnt target genes c-Myc, cyclin D1, Axin 2 and survivin was reduced by pimozide treatment in both HCT 116 and SW480 cells. CONCLUSION: Pimozide exerts anticancer effect in CRC via inhibition of wnt/ß­catenin signaling pathway, suggesting it as a potential therapeutic drug for CRC.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/prevenção & controle , Antagonistas de Dopamina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Pimozida/farmacologia , Proteína Wnt1/antagonistas & inibidores , beta Catenina/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Via de Sinalização Wnt/efeitos dos fármacos , Proteína Wnt1/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
20.
Life Sci ; 204: 71-77, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29738778

RESUMO

AIMS: Mutant EGFR Non-small cell lung cancer has benefit from gefitinib, but it has limited effect for wild-type EGFR tumors. Shikonin, a natural naphthoquinone isolated from a traditional Chinese medicine, the plant Lithospermum erythrorhizon (zicao), not only can inhibit the tumor growth, but also overcome cancer drug resistance. Our aim is to investigate whether shikonin can enhance antitumor effect of gefitinib in EGFR wild-type lung cancer cells in vitro and in vivo. MATERIALS AND METHODS: CCK-8 was used to determine the proliferation of EGFR wild-type non-small cell lung cancer. Apoptosis and cell cycle were detected by flow cytometry. PKM2, STAT3, p-STAT3 and cyclinD1 were detected by Western blot. A549 tumor model was established to observe the antitumor effect of shikonin combination with gefitinib in vivo. KEY FINDINGS: The results showed that combination of shikonin with gefitinib exhibited synergistic antitumor effect in vitro and in vivo. Its potential molecular mechanisms may be associated with inhibition of PKM2/STAT3/cyclinD1. SIGNIFICANCE: These results provide a promising therapeutic approach for the treatment of wild-type EGFR non-small cell lung cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptores ErbB/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Naftoquinonas/farmacologia , Quinazolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células A549 , Animais , Proteínas de Transporte/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/efeitos dos fármacos , Sinergismo Farmacológico , Gefitinibe , Humanos , Imuno-Histoquímica , Proteínas de Membrana/efeitos dos fármacos , Camundongos , Camundongos Nus , Fator de Transcrição STAT3/efeitos dos fármacos , Sincalida/efeitos dos fármacos , Hormônios Tireóideos , Proteínas de Ligação a Hormônio da Tireoide
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