Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Support Care Cancer ; 32(8): 561, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085696

RESUMO

Prostate cancer is one of the most common malignancies and a leading cause of death in men. Owing to its excellent anti-tumor effects, androgen deprivation therapy (ADT) is widely used in the treatment of prostate cancer. However, its use is controversial because of its potential for inducing cognitive decline. In this review, we summarized the findings of preclinical and clinical studies investigating the effects of ADT on cognitive function in prostate cancer. We discussed the methods used to assess cognitive function in these studies, elucidated the mechanisms through which ADT affects cognitive function, and highlighted recent advancements in cognitive assessment methods. The findings of this review serve as a valuable reference for examining the relationship between ADT and cognitive function in future studies. Besides, the findings may help clinicians understand the advantages and disadvantages of ADT and optimize the treatment plan so as to minimize the adverse effects of ADT.


Assuntos
Antagonistas de Androgênios , Cognição , Neoplasias da Próstata , Humanos , Antagonistas de Androgênios/efeitos adversos , Neoplasias da Próstata/tratamento farmacológico , Masculino , Cognição/efeitos dos fármacos , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/etiologia , Fatores de Risco
2.
BMC Complement Med Ther ; 24(1): 284, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39061044

RESUMO

OBJECTIVE: To evaluate the anti-tumor effector of Liuwei Dihuang Decoction (LWDHD) in prostate cancer (PCa) and explore the potential mechanism using experimental validation, network pharmacology, bioinformatics analysis, and molecular docking. METHODS: CCK test, Clone formation assay and wound-healing assays were used to determine the effect of LWDHD on prostate cancer growth and metastasis. The active ingredients and targets of LWDHD were obtained from the TCMSP database, and the relevant targets were selected by GeneCards, OMIM and DisGeNET databases for PCa. The cross-targets of drugs and disease were imported into the STRING database to construct protein interactions. The network was also visualized using Cytoscape software and core targets are screened using the Network Analyzer plug-in. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were analyzed using R software. TCGA database was used to analyze the correlation of bioinformatics genes. AutoDock vina was used to predict the molecular docking and binding ability of active ingredients to key targets. Through WB and q-PCR experiments, the above gene targets were detected to verify the effect of LWDHD on PCa. RESULTS: CCK and scratch tests confirmed that LWDHD could inhibit the proliferation, invasion and migration of prostate cancer cells. Clone formation experiments showed that LWDHD inhibited the long-term proliferative capacity of PC3 cells. LWDHD and PCa had a total of 99 common targets, establishing a "drug-ingredient-common target" network. Through GO and KEGG enrichment analysis, PI3K/AKT, MAPK, TP53 pathway, MYC, TNF pathway and other signaling pathways were found. Bioinformatics analysis showed that MYC gene was highly expressed and CCND1 and MAPK1 were low expressed in prostate cancer tissues. In addition, TP53, AKT1, MYC, TNF and CCND1 were positively correlated with MAPK1, among which AKT1 and CCND1 were most closely correlated with MAPK1. Molecular docking results showed that quercetin, kaempferol, ß-sitosterol and other main active ingredients of LWDHD treatment for PCa were combined with core proteins MAPK1 and AKT1 well. WB and q-PCR results showed that LWDHD inhibited the expression of PI3K and AKT in PC3 cells. CONCLUSION: The mechanism of LWDHD therapy for PCa is a multi-target and multi-pathway complex process, which may be related to the biological processes mediated by MAPK1 and AKT1 pathways, such as cell proliferation and inhibition of metastasis, and the regulation of signaling pathways. The PI3K/AKT signaling pathway may be a central pathway of LWDHD to inhibit prostate cancer proliferation.


Assuntos
Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , Farmacologia em Rede , Neoplasias da Próstata , Masculino , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Neoplasias da Próstata/tratamento farmacológico , Humanos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Mapas de Interação de Proteínas
3.
Pharmacol Res ; 199: 107032, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38061594

RESUMO

Cancer is a leading cause of death worldwide. The burden of cancer incidence and mortality is increasing rapidly. New approaches to cancer prevention and treatment are urgently needed. Natural products are reliable and powerful sources for anticancer drug discovery. Baicalin and baicalein, two major flavones isolated from Scutellaria baicalensis Georgi, a multi-purpose traditional medicinal plant in China, exhibit anticancer activities against multiple cancers. Of note, these phytochemicals exhibit extremely low toxicity to normal cells. Besides their cytotoxic and cytostatic activities toward diverse tumor cells, recent studies demonstrated that baicalin and baicalein modulate a variety of tumor stromal cells and extracellular matrix (ECM) in the tumor microenvironment (TME), which is essential for tumorigenesis, cancer progression and metastasis. In this review, we summarize the therapeutic potential and the mechanism of action of baicalin and baicalein in the regulation of tumor microenvironmental immune cells, endothelial cells, fibroblasts, and ECM that reshape the TME and cancer signaling, leading to inhibition of tumor angiogenesis, progression, and metastasis. In addition, we discuss the biotransformation pathways of baicalin and baicalein, related therapeutic challenges and the future research directions to improve their bioavailability and clinical anticancer applications. Recent advances of baicalin and baicalein warrant their continued study as important natural ways for cancer interception and therapy.


Assuntos
Flavanonas , Neoplasias , Humanos , Microambiente Tumoral , Células Endoteliais/metabolismo , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Flavonoides/metabolismo , Flavanonas/farmacologia , Flavanonas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia
4.
J Ethnopharmacol ; 308: 116333, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36863640

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Contemporary therapy for advanced castration-resistant prostate cancer (CRPC) employs reagents such as enzalutamide and abiraterone acetate targeting the androgen receptor (AR) transcription axis only provide a temporary response and rapidly develop resistance. Additionally, neuroendocrine prostate cancer (NEPC) is an AR pathway-independent and lethal-stage prostate cancer with no standard therapy. Qingdai Decoction (QDT), a traditional Chinese medicine formula, has various pharmacological activities and was widely used for the treatment of different diseases including prostatitis which may contribute to prostate cancer development. AIM OF THE STUDY: This study aims to explore the anti-tumor role and potential mechanism of QDT on prostate cancer. MATERIAL AND METHODS: CRPC prostate cancer cell models and xenograft mice models were established for research. The effect of TCMs on cancer growth and metastasis were determined by CCK-8, wound-healing assays and the PC3-xenografted mice model. The toxicity of QDT in the major organs was investigated by H&E staining. The compound-target network was analyzed with network pharmacology. The correlation of QDT targets with prostate cancer patient's prognosis was analyzed with multiple prostate cancer patient cohorts. The expression of related proteins and mRNA were detected by western blot and real-time PCR. The gene knockdown was achieved with CRISPR-Cas13 technology. RESULTS: By integrating functional screening, network pharmacology analysis, CRISPR-Cas13 directed RNA targeting, and molecular biology validation in different prostate cancer models and clinical prostate cancer cohorts, we found that Qingdai Decoction (QDT), a Traditional Chinese Medicine, can repress cancer growth in advanced prostate cancer models in vitro and in vivo in an AR independent manner by targeting NOS3, TGFB1, and NCOA2. CONCLUSION: This study not only identified QDT as a novel drug for lethal-stage prostate cancer treatment but also provided an extensive Integrative research paradigm for investigating the roles and mechanisms of TCMs for the treatment of other diseases.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Animais , Camundongos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Receptores Androgênicos/metabolismo , Proliferação de Células , Próstata/patologia , Nitrilas , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos
5.
Int J Mol Sci ; 24(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36674985

RESUMO

Colorectal cancer (CRC) is a major health burden worldwide due to its high morbidity, mortality, and complex etiology. Fusobacterium nucleatum (Fn), a Gram-negative anaerobe found in 30% of CRC patients, promotes CRC carcinogenesis, metastasis, and chemoresistance. Effective antimicrobial treatment is an unmet need for the rising CRC burden. Antimicrobial peptides (AMPs) represent a new class of antimicrobial drugs. In our previous study, we did the structure-activity study of Jelleine-I (J-I) and identified several halogenated J-I derivatives Cl-J-I, Br-J-I, and I-J-I. To determine whether those J-I derivatives can be a new therapy for bacterial-associated CRC, here we tested the antibacterial activities of these AMPs against Fn and their effects on CRC development. We found that Br-J-I showed the highest anti-Fn activity and Br-J-I may target membrane-associated FadA for Fn membrane disruption. More importantly, Fn promoted the growth of CRC cells-derived xenograft tumors. Br-J-I suppressed Fn load, colon inflammation, and Fn-induced CRC growth. Of note, Br-J-I induced better anti-CRC effects than common antibiotic metronidazole and Br-J-I sensitized the cancer-killing effect of chemotherapy drug 5-fluorouracil. These results suggest that Br-J-I could be considered as an adjunctive agent for CRC treatment and AMPs-based combination treatment is a new strategy for CRC in the future.


Assuntos
Anti-Infecciosos , Colite , Neoplasias Colorretais , Humanos , Fusobacterium nucleatum , Neoplasias Colorretais/etiologia , Carcinogênese , Colite/complicações
6.
Cells ; 11(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36497071

RESUMO

The liver is the most common site for colorectal cancer (CRC)-associated metastasis. There remain unsatisfactory medications in liver metastasis given the incomplete understanding of pathogenic mechanisms. Herein, with an orthotopic implantation model fed either regular or high-fat diets (HFD), more liver metastases were associated with an expansion of conjugated bile acids (BAs), particularly taurocholic acid (TCA) in the liver, and an increased gene expression of Na+-taurocholate cotransporting polypeptide (NTCP). Such hepatic BA change was more apparently shown in the HFD group. In the same model, TCA was proven to promote liver metastases and induce a tumor-favorable microenvironment in the liver, characterizing a high level of fibroblast activation and increased proportions of myeloid-derived immune cells. Hepatic stellate cells, a liver-residing source of fibroblasts, were dose-dependently activated by TCA, and their conditioned medium significantly enhanced the migration capability of CRC cells. Blocking hepatic BA uptake with NTCP neutralized antibody can effectively repress TCA-triggered liver metastases, with an evident suppression of tumor microenvironment niche formation. This study points to a new BA-driven mechanism of CRC-associated liver metastases, suggesting that a reduction of TCA overexposure by limiting liver uptake is a potential therapeutic option for CRC-associated liver metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Simportadores , Humanos , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Simportadores/genética , Simportadores/metabolismo , Ácido Taurocólico/farmacologia , Ácido Taurocólico/metabolismo , Microambiente Tumoral
7.
Life Sci ; 307: 120848, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940221

RESUMO

AIMS: In this study, we will examine if RSL1D1 influences PPARγ expression and explore the underlying mechanism that RSL1D1 regulates PPARγ expression. Moreover, the significance of RSL1D1-PPARγ pathway in cell senescence and proliferation will also be determined. MAIN METHODS: Our main methods include western blotting, immunoprecipitation (IP), real-time PCR, RNA Immunoprecipitation (RIP), biotin-labeled RNA pull down assay, dual luciferase reporter gene assay, senescence-associated ß-galactosidase staining, cell proliferation assay, colony formation assay, wound healing assay, blood biochemistry test and Oil red O staining. KEY FINDINGS: By analyzing gene chip results we find that the expression of RSL1D1 and PPARγ might be correlated. Then we show that RSL1D1 is a posttranscriptional regulator of PPARγ. RSL1D1 overexpression elevates, while RSL1D1 knockdown inhibits, PPARγ mRNA and protein expression levels. Mechanistically, we find that RSL1D1 directly interacts with the 3'-untranslated region of PPARγ mRNA, and then promotes its stability and increases PPARγ protein expression level. We further demonstrate that RSL1D1 modulates cellular senescence and cell proliferation partially via PPARγ-regulated downstream target genes such as PTEN/p27, NF-κB, GLUT4, and ACL. Moreover, we find that RSL1D1 regulates PPARγ expression and function in a HuR-dependent manner. Last, we show that RSL1D1 knockout in mouse adipose tissue shortens mouse lifespan and leads to hepatic damage which may impair liver damage repair function. SIGNIFICANCE: Collectively, our findings unveil a novel posttranscriptional regulation of PPARγ by RSL1D1 and uncover a critical role of RSL1D1-PPARγ-PPARγ downstream target genes in regulating cellular senescence and cell proliferation.


Assuntos
NF-kappa B , PPAR gama , Proteínas da Gravidez , Proteínas Ribossômicas , Animais , Camundongos , Regiões 3' não Traduzidas , beta-Galactosidase/metabolismo , Biotina , Proliferação de Células , Senescência Celular/genética , NF-kappa B/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Proteínas da Gravidez/metabolismo , Proteínas Ribossômicas/metabolismo , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
Nat Chem Biol ; 18(10): 1056-1064, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35879545

RESUMO

SARS-CoV-2 entry into cells requires specific host proteases; however, no successful in vivo applications of host protease inhibitors have yet been reported for treatment of SARS-CoV-2 pathogenesis. Here we describe a chemically engineered nanosystem encapsulating CRISPR-Cas13d, developed to specifically target lung protease cathepsin L (Ctsl) messenger RNA to block SARS-CoV-2 infection in mice. We show that this nanosystem decreases lung Ctsl expression in normal mice efficiently, specifically and safely. We further show that this approach extends survival of mice lethally infected with SARS-CoV-2, correlating with decreased lung virus burden, reduced expression of proinflammatory cytokines/chemokines and diminished severity of pulmonary interstitial inflammation. Postinfection treatment by this nanosystem dramatically lowers the lung virus burden and alleviates virus-induced pathological changes. Our results indicate that targeting lung protease mRNA by Cas13d nanosystem represents a unique strategy for controlling SARS-CoV-2 infection and demonstrate that CRISPR can be used as a potential treatment for SARS-CoV-2 infection.


Assuntos
Tratamento Farmacológico da COVID-19 , Animais , Catepsina L , Quimiocinas , Citocinas , Endopeptidases , Pulmão/patologia , Camundongos , Peptídeo Hidrolases , Inibidores de Proteases/farmacologia , RNA Mensageiro/genética , SARS-CoV-2
9.
Cell Death Dis ; 13(7): 632, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35864113

RESUMO

Prostate cancer is a hormone-dependent malignancy, whose onset and progression are closely related to the activity of the androgen receptor (AR) signaling pathway. Due to this critical role of AR signaling in driving prostate cancer, therapy targeting the AR pathway has been the mainstay strategy for metastatic prostate cancer treatment. The utility of these agents has expanded with the emergence of second-generation AR antagonists, which began with the approval of enzalutamide in 2012 by the United States Food and Drug Administration (FDA). Together with apalutamide and darolutamide, which were approved in 2018 and 2019, respectively, these agents have improved the survival of patients with prostate cancer, with applications for both androgen-dependent and castration-resistant disease. While patients receiving these drugs receive a benefit in the form of prolonged survival, they are not cured and ultimately progress to lethal neuroendocrine prostate cancer (NEPC). Here we summarize the current state of AR antagonist development and highlight the emerging challenges of their clinical application and the potential resistance mechanisms, which might be addressed by combination therapies or the development of novel AR-targeted therapies.


Assuntos
Antagonistas de Receptores de Andrógenos , Neoplasias de Próstata Resistentes à Castração , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Androgênios/farmacologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/metabolismo
10.
Nucleic Acids Res ; 50(8): 4450-4463, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35394046

RESUMO

Mediator activates RNA polymerase II (Pol II) function during transcription, but it remains unclear whether Mediator is able to travel with Pol II and regulate Pol II transcription beyond the initiation and early elongation steps. By using in vitro and in vivo transcription recycling assays, we find that human Mediator 1 (MED1), when phosphorylated at the mammal-specific threonine 1032 by cyclin-dependent kinase 9 (CDK9), dynamically moves along with Pol II throughout the transcribed genes to drive Pol II recycling after the initial round of transcription. Mechanistically, MED31 mediates the recycling of phosphorylated MED1 and Pol II, enhancing mRNA output during the transcription recycling process. Importantly, MED1 phosphorylation increases during prostate cancer progression to the lethal phase, and pharmacological inhibition of CDK9 decreases prostate tumor growth by decreasing MED1 phosphorylation and Pol II recycling. Our results reveal a novel role of MED1 in Pol II transcription and identify phosphorylated MED1 as a targetable driver of dysregulated Pol II recycling in cancer.


Assuntos
Neoplasias , RNA Polimerase II , Animais , Humanos , Masculino , Mamíferos/genética , Complexo Mediador/metabolismo , Subunidade 1 do Complexo Mediador/genética , Neoplasias/genética , Fosforilação , RNA Polimerase II/metabolismo , Transcrição Gênica
11.
Genes Dis ; 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36591005

RESUMO

The ongoing global pandemic of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in over 570 million infections and 6 million deaths worldwide. Early detection and quarantine are essential to arrest the spread of the highly contagious COVID-19. High-risk groups, such as older adults and individuals with comorbidities, can present severe symptoms, including pyrexia, pertussis, and acute respiratory distress syndrome, on SARS-CoV-2 infection that can prove fatal, demonstrating a clear need for high-throughput and sensitive platforms to detect and eliminate SARS-CoV-2. CRISPR-Cas13, an emerging CRISPR system targeting RNA with high specificity and efficiency, has recently drawn much attention for COVID-19 diagnosis and treatment. Here, we summarized the current research progress on CRISPR-Cas13 in COVID-19 diagnosis and treatment and highlight the challenges and future research directions of CRISPR-Cas13 for effectively counteracting COVID-19.

12.
Genes Dis ; 8(1): 61-72, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33569514

RESUMO

Alternative polyadenylation (APA) is a molecular process that generates diversity at the 3' end of RNA polymerase II transcripts from over 60% of human genes. APA is derived from the existence of multiple polyadenylation signals (PAS) within the same transcript, and results in the differential inclusion of sequence information at the 3' end. While APA can occur between two PASs allowing for generation of transcripts with distinct coding potential from a single gene, most APA occurs within the untranslated region (3'UTR) and changes the length and content of these non-coding sequences. APA within the 3'UTR can have tremendous impact on its regulatory potential of the mRNA through a variety of mechanisms, and indeed this layer of gene expression regulation has profound impact on processes vital to cell growth and development. Recent studies have particularly highlighted the importance of APA dysregulation in cancer onset and progression. Here, we review the current knowledge of APA and its impacts on mRNA stability, translation, localization and protein localization. We also discuss the implications of APA dysregulation in cancer research and therapy.

13.
Transl Oncol ; 13(9): 100797, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32454444

RESUMO

Widespread cGMP-specific phosphodiesterase 5 (PDE5) inhibitor use in male reproductive health and particularly in prostate cancer patients following surgery has generated interest in how these drugs affect the ability of residual tumor cells to proliferate, migrate, and form recurrent colonies. Prostate cancer cell lines were treated with PDE5 inhibitors at clinically relevant concentrations. Proliferation, colony formation, and migration phenotypes remained stable even when cells were co-treated with a stimulator of cGMP synthesis that facilitated cGMP accumulation upon PDE5 inhibition. Surprisingly, supraclinical concentrations of PDE5 inhibitor counteracted proliferation, colony formation, and migration of prostate cancer cell models. These findings provide tumor cell-autonomous evidence in support of the field's predominant view that PDE5 inhibitors are safe adjuvant agents to promote functional recovery of normal tissue after prostatectomy, but do not rule out potential cancer-promoting effects of PDE5 inhibitors in the more complex environment of the prostate.

14.
Nucleic Acids Res ; 47(19): 10104-10114, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31501863

RESUMO

Enzalutamide, a second-generation androgen receptor (AR) antagonist, has demonstrated clinical benefit in men with prostate cancer. However, it only provides a temporary response and modest increase in survival, indicating a rapid evolution of resistance. Previous studies suggest that enzalutamide may function as a partial transcriptional agonist, but the underlying mechanisms for enzalutamide-induced transcription remain poorly understood. Here, we show that enzalutamide stimulates expression of a novel subset of genes distinct from androgen-responsive genes. Treatment of prostate cancer cells with enzalutamide enhances recruitment of pioneer factor GATA2, AR, Mediator subunits MED1 and MED14, and RNA Pol II to regulatory elements of enzalutamide-responsive genes. Mechanistically, GATA2 globally directs enzalutamide-induced transcription by facilitating AR, Mediator and Pol II loading to enzalutamide-responsive gene loci. Importantly, the GATA2 inhibitor K7174 inhibits enzalutamide-induced transcription by decreasing binding of the GATA2/AR/Mediator/Pol II transcriptional complex, contributing to sensitization of prostate cancer cells to enzalutamide treatment. Our findings provide mechanistic insight into the future combination of GATA2 inhibitors and enzalutamide for improved AR-targeted therapy.


Assuntos
Fator de Transcrição GATA2/genética , Feniltioidantoína/análogos & derivados , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/genética , Antagonistas de Receptores de Andrógenos/farmacologia , Benzamidas , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Fator de Transcrição GATA2/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Complexo Mediador/genética , Subunidade 1 do Complexo Mediador/genética , Nitrilas , Feniltioidantoína/farmacologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Polimerase II/genética
15.
Cell Death Dis ; 9(5): 518, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29725012

RESUMO

The nucleolus is an important organelle that is responsible for the biogenesis of ribosome RNA (rRNA) and ribosomal subunits assembly. It is also deemed to be the center of metabolic control, considering the critical role of ribosomes in protein translation. Perturbations of rRNA synthesis are closely related to cell proliferation and tumor progression. Telomeric repeat-binding factor 2 (TRF2) is a member of shelterin complex that is responsible for telomere DNA protection. Interestingly, it was recently reported to localize in the nucleolus of human cells in a cell-cycle-dependent manner, while the underlying mechanism and its role on the nucleolus remained unclear. In this study, we found that nucleolar and coiled-body phosphoprotein 1 (NOLC1), a nucleolar protein that is responsible for the nucleolus construction and rRNA synthesis, interacted with TRF2 and mediated the shuttle of TRF2 between the nucleolus and nucleus. Abating the expression of NOLC1 decreased the nucleolar-resident TRF2. Besides, the nucleolar TRF2 could bind rDNA and promoted rRNA transcription. Furthermore, in hepatocellular carcinoma (HCC) cell lines HepG2 and SMMC7721, TRF2 overexpression participated in the nucleolus stress-induced rRNA inhibition and cell-cycle arrest.


Assuntos
Antineoplásicos/farmacologia , Nucléolo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Proteínas Nucleares/genética , Fosfoproteínas/genética , RNA Ribossômico/genética , Proteína 2 de Ligação a Repetições Teloméricas/genética , Sequência de Aminoácidos , Camptotecina/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Nucléolo Celular/metabolismo , Nucléolo Celular/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Dactinomicina/farmacologia , Etoposídeo/farmacologia , Células HEK293 , Células Hep G2 , Humanos , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/metabolismo , Ligação Proteica , Transporte Proteico , RNA Ribossômico/biossíntese , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ribossomos/efeitos dos fármacos , Ribossomos/genética , Ribossomos/metabolismo , Transdução de Sinais , Proteína 2 de Ligação a Repetições Teloméricas/antagonistas & inibidores , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo
16.
J Biol Chem ; 293(19): 7268-7280, 2018 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-29581234

RESUMO

DNA damage-induced NF-κB activation and the secretion of inflammatory cytokines play crucial roles in carcinogenesis and cellular senescence. However, the underlying mechanisms, especially the initial sensors and transducers connecting the nuclear DNA damage signal with cytoplasmic NF-κB activation remain incompletely understood. Here, we report that TRAF-interacting protein with forkhead-associated domain (TIFA), an established NF-κB activator in the cytosol, unexpectedly exhibited nuclear translocation and accumulation on damaged chromatin following genotoxic stress. Accordingly, we also found that DNA damage-induced transcriptional activation and the resulting secretion of classic NF-κB targets, including interleukin (IL)-6 and IL-8, was greatly enhanced in TIFA-overexpressing cells compared with control cells. Mechanistically, DNA damage-induced TIFA phosphorylation at threonine 9 (pThr-9), and this phosphorylation event, involving the pThr-binding forkhead-associated domain, was crucial for its enrichment on damaged chromatin and subsequent NF-κB activation. Moreover, in conjunction with its partner protein, the E3 ligase TNF receptor-associated factor 2 (TRAF2), TIFA relayed the DNA damage signals by stimulating ubiquitination of NF-κB essential modulator (NEMO), whose sumoylation, phosphorylation, and ubiquitination were critical for NF-κB's response to DNA damage. Consistently, TRAF2 knockdown suppressed TIFA overexpression-enhanced NEMO ubiquitination under genotoxic stress, and a unphosphorylatable Thr-9-mutated TIFA variant had only minor effects on NEMO poly-ubiquitination. Finally, in agreement with the model of DNA damage-associated secretory senescence barrier against carcinogenesis, ectopic TIFA expression limited proliferation of multiple myeloma cancer cells. In conclusion our results indicate that TIFA functions as a key transducer in DNA damage-induced NF-κB activation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Dano ao DNA , NF-kappa B/metabolismo , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Carcinogênese , Proliferação de Células , Cromatina/metabolismo , Células HEK293 , Células HeLa , Humanos , Quinase I-kappa B/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Mutagênicos/toxicidade , Fosforilação , Ligação Proteica , Transdução de Sinais , Fator 2 Associado a Receptor de TNF/metabolismo , Ubiquitinação
17.
Cell Death Discov ; 3: 17043, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28875039

RESUMO

Telomeric repeat-binding factor 2 (TRF2) was reported to localize in the nucleolus of human cells in a cell cycle-dependent manner; however, the underlying mechanism remains unclear. Here, we found that nucleolar and coiled-body phosphoprotein 1 (NOLC1) interacted with TRF2 and mediated the shuttling of TRF2 between the nucleolus and nucleus in human 293T and HepG2 cells. Ablation of NOLC1 expression increased the number of nuclear TRF2 foci and decreased the nucleolar level of TRF2. Conversely, NOLC1 overexpression promoted the nucleolar accumulation of TRF2. NOLC1 overexpression also increased the number of 53BP1 foci and induced the DNA damage response. In addition, co-expression of TRF2 rescued NOLC1 overexpression-induced cell cycle arrest and apoptosis.

18.
Aging Cell ; 16(4): 726-737, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28493459

RESUMO

The nucleolus is a key organelle that is responsible for the synthesis of rRNA and assembly of ribosomal subunits, which is also the center of metabolic control because of the critical role of ribosomes in protein synthesis. Perturbations of rRNA biogenesis are closely related to cell senescence and tumor progression; however, the underlying molecular mechanisms are not well understood. Here, we report that cellular senescence-inhibited gene (CSIG) knockdown up-regulated NOLC1 by stabilizing the 5'UTR of NOLC1 mRNA, and elevated NOLC1 induced the retention of NOG1 in the nucleolus, which is responsible for rRNA processing. Besides, the expression of NOLC1 was negatively correlated with CSIG in the aged mouse tissue and replicative senescent 2BS cells, and the down-regulation of NOLC1 could rescue CSIG knockdown-induced 2BS senescence. Additionally, NOLC1 expression was decreased in human hepatocellular carcinoma (HCC) tissue, and the ectopic expression of NOLC1 repressed the proliferation of HCC cells and tumor growth in a HCC xenograft model.


Assuntos
Envelhecimento/genética , Carcinoma Hepatocelular/genética , Nucléolo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Proteínas Nucleares/genética , Fosfoproteínas/genética , Proteínas Ribossômicas/genética , Regiões 5' não Traduzidas , Envelhecimento/metabolismo , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Nucléolo Celular/genética , Nucléolo Celular/ultraestrutura , Proliferação de Células , Senescência Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Células HEK293 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/metabolismo , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/metabolismo
19.
Sci Rep ; 6: 36171, 2016 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-27811966

RESUMO

Nucleolar proteins play an important role in the regulation of the MDM2-p53 pathway, which coordinates cellular response to stress. However, the mechanism underlying this regulation remains poorly understood. Here, we report that the nucleolar protein CSIG is a novel and crucial regulator of the MDM2-p53 pathway. We demonstrate that CSIG translocates from the nucleolus to the nucleoplasm in response to nucleolar stress. Moreover, knockdown of CSIG attenuates the induction of p53 and abrogates G1 phase arrest in response to nucleolar stress. CSIG interacts directly with the MDM2 RING finger domain and inhibits MDM2 E3 ubiquitin ligase activity, thus resulting in a decrease in MDM2-mediated p53 ubiquitination and degradation. Our results suggest that the CSIG-MDM2-p53 regulatory pathway plays an important role in the cellular response to nucleolar stress.


Assuntos
Nucléolo Celular/metabolismo , Proteínas da Gravidez/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Ribossômicas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Transporte Ativo do Núcleo Celular , Linhagem Celular , Pontos de Checagem da Fase G1 do Ciclo Celular , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Células MCF-7 , Proteínas da Gravidez/antagonistas & inibidores , Proteínas da Gravidez/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , RNA Ribossômico/metabolismo , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/genética , Transdução de Sinais , Estresse Fisiológico , Ubiquitinação
20.
PLoS One ; 10(10): e0141678, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26517370

RESUMO

Nucleostemin (NS) is a GTP-binding protein that is predominantly expressed in embryonic and adult stem cells but not in terminally differentiated cells. NS plays an essential role in maintaining the continuous proliferation of stem cells and some types of cancer cells. However, the role of NS in hepatocellular carcinoma (HCC) remains unclear. Therefore, this study aimed to clarify the role of NS in HCC. First, we demonstrated high expression of NS in most HCC cell lines and liver cancer tissues. NS knockdown induced a severe decline in cell viability of MHCC97H cells as detected by MTT and cell proliferation assays. Next, we used ultraviolet (UV) and serum starvation-induced apoptosis models to investigate whether NS suppression or up-regulation affects HCC cell apoptosis. After UV treatment or serum starvation, apoptosis was strongly enhanced in MHCC97H and Bel7402 cells transfected with small interfering RNA against NS, whereas NS overexpression inhibited UV- and serum-induced apoptosis of HCC cells. Furthermore, after UV irradiation, inhibition of NS increased the expression of pro-apoptosis protein caspase 3 and decreased the expression of anti-apoptosis protein Bcl-2. A caspase 3 inhibitor could obviously prevent NS knockdown-induced apoptosis. In conclusion, our study demonstrated overexpression of NS in most HCC tissues compared with their matched surrounding tissues, and silencing NS promoted UV- and serum starvation-induced apoptosis of MHCC97H and Bel7402 cells. Therefore, the NS gene might be a potential therapeutic target of HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Meios de Cultura Livres de Soro/farmacologia , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Adulto , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA