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1.
J Clin Sleep Med ; 20(6): 941-946, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38318919

RESUMO

STUDY OBJECTIVES: Narcolepsy type 1 is attributed to a deficiency in cerebrospinal fluid orexin and is considered linked to autoimmunity. The levels of anti-Tribbles homolog 2 (TRIB2) autoantibodies are elevated in the sera of some patients with narcolepsy with cataplexy. Additionally, injecting mice with serum immunoglobulin from patients with narcolepsy with positive anti-TRIB2 antibodies can induce hypothalamic neuron loss and alterations in sleep patterns. Consequently, we hypothesized the existence of a potential association between anti-TRIB2 antibodies and narcolepsy. To test this possibility, we used cell-based assays (CBAs) and enzyme-linked immunosorbent assays (ELISAs) to detect the presence of anti-TRIB2 antibodies in Chinese patients with narcolepsy. METHODS: We included 68 patients with narcolepsy type 1, 39 patients with other central disorders of hypersomnolence, and 43 healthy controls. A CBA and a conventional ELISA were used to detect anti-TRIB2 antibody levels in patients' sera. RESULTS: CBA was used to detect serum anti-TRIB2 antibodies in Chinese patients with narcolepsy, and the results were negative. However, when the ELISA was used, only 2 patients with narcolepsy type 1 had TRIB2 antibody titers higher than the mean titer plus 2 standard deviations of the healthy controls. CONCLUSIONS: In our study, ELISA identified TRIB2 autoantibodies in sera of patients with narcolepsy where CBA failed to demonstrate them. Contrary to our hypothesis, this intriguing finding deserves further research to elucidate the potential association between TRIB2 and narcolepsy type 1. Exploring the implications of TRIB2 autoantibodies in narcolepsy and disparate outcomes between ELISA and CBA could provide crucial insights. CITATION: Zhong X, Yuan Y, Zhan Q, et al. Cell-based vs enzyme-linked immunosorbent assay for detection of anti-Tribbles homolog 2 autoantibodies in Chinese patients with narcolepsy. J Clin Sleep Med. 2024;20(6):941-946.


Assuntos
Autoanticorpos , Ensaio de Imunoadsorção Enzimática , Narcolepsia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Autoanticorpos/sangue , Proteínas Quinases Dependentes de Cálcio-Calmodulina/imunologia , China , População do Leste Asiático , Ensaio de Imunoadsorção Enzimática/métodos , Narcolepsia/imunologia
2.
Int J Mol Sci ; 24(10)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37240251

RESUMO

MicroRNAs (miRNAs) are endogenous small non-coding RNAs that play crucial regulatory roles in many biological processes, including the growth and development of skeletal muscle. miRNA-100-5p is often associated with tumor cell proliferation and migration. This study aimed to uncover the regulatory mechanism of miRNA-100-5p in myogenesis. In our study, we found that the miRNA-100-5p expression level was significantly higher in muscle tissue than in other tissues in pigs. Functionally, this study shows that miR-100-5p overexpression significantly promotes the proliferation and inhibits the differentiation of C2C12 myoblasts, whereas miR-100-5p inhibition results in the opposite effects. Bioinformatic analysis predicted that Trib2 has potential binding sites for miR-100-5p at the 3'UTR region. A dual-luciferase assay, qRT-qPCR, and Western blot confirmed that Trib2 is a target gene of miR-100-5p. We further explored the function of Trib2 in myogenesis and found that Trib2 knockdown markedly facilitated proliferation but suppressed the differentiation of C2C12 myoblasts, which is contrary to the effects of miR-100-5p. In addition, co-transfection experiments demonstrated that Trib2 knockdown could attenuate the effects of miR-100-5p inhibition on C2C12 myoblasts differentiation. In terms of the molecular mechanism, miR-100-5p suppressed C2C12 myoblasts differentiation by inactivating the mTOR/S6K signaling pathway. Taken together, our study results indicate that miR-100-5p regulates skeletal muscle myogenesis through the Trib2/mTOR/S6K signaling pathway.


Assuntos
MicroRNAs , Transdução de Sinais , Animais , Suínos , Linhagem Celular , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Diferenciação Celular/genética , Músculo Esquelético/metabolismo , Desenvolvimento Muscular/genética , Proliferação de Células/genética
3.
Cell Rep ; 42(3): 112195, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36884349

RESUMO

Naive CD4+ T cells are more resistant to age-related loss than naive CD8+ T cells, suggesting mechanisms that preferentially protect naive CD4+ T cells during aging. Here, we show that TRIB2 is more abundant in naive CD4+ than CD8+ T cells and counteracts quiescence exit by suppressing AKT activation. TRIB2 deficiency increases AKT activity and accelerates proliferation and differentiation in response to interleukin-7 (IL-7) in humans and during lymphopenia in mice. TRIB2 transcription is controlled by the lineage-determining transcription factors ThPOK and RUNX3. Ablation of Zbtb7b (encoding ThPOK) and Cbfb (obligatory RUNT cofactor) attenuates the difference in lymphopenia-induced proliferation between naive CD4+ and CD8+ cells. In older adults, ThPOK and TRIB2 expression wanes in naive CD4+ T cells, causing loss of naivety. These findings assign TRIB2 a key role in regulating T cell homeostasis and provide a model to explain the lesser resilience of CD8+ T cells to undergo changes with age.


Assuntos
Linfócitos T CD8-Positivos , Linfopenia , Idoso , Animais , Humanos , Camundongos , Envelhecimento , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Homeostase , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição/metabolismo
4.
Cell Biol Int ; 47(4): 787-795, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36626273

RESUMO

Tribbles homolog 2 (TRIB2) functions as an adapter protein that regulates signal transductions involved in a variety of cellular functions, including tumorigenesis. However, the role of TRIB2 in the proliferation of vascular smooth muscle cells (VSMCs) and the underlying expression mechanisms remain unclear. The present study investigated the role of TRIB2 in VSMC proliferation and revealed that TRIB2 expression increases following vascular injury and platelet-derived growth factor (PDGF)-BB-stimulated VSMCs. We found that pretreatment with diphenyleneiodonium (a nicotinamide adenine dinucleotide phosphate oxidase inhibitor), U0126 (an inhibitor of mitogen-activated protein kinase kinase 1 [MEK1]), or siRNA targeting the gene encoding early growth response 1 (EGR-1) significantly inhibits PDGF-BB-induced TRIB2 expression in VSMCs. Furthermore, TRIB2 knockdown significantly inhibits PDGF-BB-induced proliferation of VSMCs but does not affect the phosphorylation of AKT. However, phosphorylation of ERK1 and expression of proliferating cell nuclear antibody are significantly suppressed in VSMCs by PDGF-BB stimulation. Thus, PDGF-BB-induced TRIB2 expression is mediated by ROS/ERK/EGR-1 pathways and plays a critical role in VSMC proliferation via modulation of ERK activity. We propose TRIB2 as a promising therapeutic target for the prevention of neointima formation and vascular disease.


Assuntos
Proliferação de Células , Músculo Liso Vascular , Transdução de Sinais , Animais , Ratos , Becaplermina/metabolismo , Becaplermina/farmacologia , Movimento Celular , Proliferação de Células/genética , Células Cultivadas , Sistema de Sinalização das MAP Quinases , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo
5.
Anim Biotechnol ; 34(7): 2846-2854, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36125800

RESUMO

Tribbles homolog 2 (TRIB2) plays an important role in the follicular development of female mammals. However, its expression and function in the yak (Bos grunniens) are still unclear. In this study, we predicted the molecular characteristics of TRIB2, and revealed its expression pattern in yak (Bos grunniens) tissues and ovarian granulosa cells. We cloned the full length of the yak TRIB2 gene obtained by RT-PCR was 1368 bp and the coding sequence (CDS) was 624 bp, encoding 207 amino acids (AA). Homology analysis showed that the yak TRIB2 is highly conserved among species. TRIB2 was detected to be extensively expressed in seven tissues of the yak liver, spleen, lung, kidney, ovary, oviduct and uterus by qPCR. The expression of TRIB2 mRNA in the ovary during gestation was significantly lower than that in the non-pregnant (p < 0.05). At each stage of follicle development, the TRIB2 mRNA in granulosa cells showed a significant upward trend with the development of follicles. The expression of TRIB2 gradually decreased with the increase of the culture time of the granulosa cells in vitro. In conclusion, these results suggest that TRIB2 may play an important role in the follicular development of yaks.


Assuntos
Ovário , Útero , Bovinos/genética , Feminino , Animais , Sequência de Aminoácidos , Ovário/metabolismo , Útero/metabolismo , Células da Granulosa/metabolismo , RNA Mensageiro/genética , Mamíferos/genética , Mamíferos/metabolismo
6.
Genes (Basel) ; 15(1)2023 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-38254916

RESUMO

Tribbles pseudokinases (TRIB1-3) are important signaling modulators involved in several cancers. However, their function in gastric cancer (GC) remains undefined. GC is still a deadly disease since the lack of sensitive and specific biomarkers for early diagnosis and therapy response prediction negatively affects patients' outcome. The identification of novel molecular players may lead to more effective diagnostic and therapeutic avenues. Therefore, we investigated the role of TRIB genes in gastric tumorigenesis. Data mining of the TCGA dataset revealed that chromosomal instability (CIN) tumors have lower TRIB2 and higher TRIB3 expression versus microsatellite instability (MSI)-high tumors, while TRIB1 levels are similar in both tumor types. Moreover, in CIN tumors, low TRIB2 expression is significantly associated with aggressive stage IV disease. As no studies on TRIB2 in GC are available, we focused on this gene for further in vitro analyses. We checked the effect of TRIB2 overexpression (OE) on MKN45 and NCI-N87 CIN GC cell lines. In MKN45 cells, TRIB2 OE reduced proliferation and colony formation ability and induced G2/M arrest, while it decreased the proliferation and cell motility of NCI-N87 cells. These effects were not mediated by the MAPK pathway. Our results suggest a tumor-suppressive function of TRIB2 in GC with a CIN phenotype.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Apoptose , Linhagem Celular Tumoral , Pontos de Checagem da Fase G2 do Ciclo Celular , Instabilidade Cromossômica , Proteínas Quinases Dependentes de Cálcio-Calmodulina , Proteínas Serina-Treonina Quinases/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética
7.
Structure ; 30(11): 1518-1529.e5, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36108635

RESUMO

Tribbles proteins (TRIB1-3) are pseudokinases that recruit substrates to the COP1 ubiquitin ligase. TRIB2 was the first Tribbles ortholog to be implicated as a myeloid leukemia oncogene, because it recruits the C/EBPα transcription factor for ubiquitination by COP1. Here we report identification of nanobodies that bind the TRIB2 pseudokinase domain with low nanomolar affinity. A crystal structure of the TRIB2-Nb4.103 complex identified the nanobody to bind the N-terminal lobe of TRIB2, enabling specific recognition of TRIB2 in an activated conformation that is similar to the C/EBPα-bound state of TRIB1. Characterization in solution revealed that Nb4.103 can stabilize a TRIB2 pseudokinase domain dimer in a face-to-face manner. Conversely, a distinct nanobody (Nb4.101) binds through a similar epitope but does not readily promote dimerization. In combination, this study identifies features of TRIB2 that could be exploited for the development of inhibitors and nanobody tools for future investigation of TRIB2 function.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Anticorpos de Domínio Único , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/genética , Anticorpos de Domínio Único/metabolismo , Ubiquitina/metabolismo , Ubiquitinação
8.
Methods Enzymol ; 667: 37-58, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35525548

RESUMO

Tribbles proteins are pervasive pseudokinases in cellular signaling. They play a major role in the differentiation of myeloid cells, hepatocytes and adipocytes, and more widely in immune function, metabolism and cancer. Like many other pseudokinases, an inherent lack of catalytic activity has meant that a specialized cadre of techniques has been required to investigate Tribbles function. A prerequisite to most in vitro biochemistry has been robust methods for purifying useful quantities of Tribbles protein, which can sometimes exhibit non-optimal behavior upon recombinant expression. For instance, structural studies of the Tribbles family have largely focused on TRIB1, in part because of more readily available protein. Here we describe methods we have developed to routinely produce milligram quantities of TRIB1, and specific considerations when employing TRIB1 protein for various downstream analyses. Namely, we describe preparation and crystallization of TRIB1 for structural studies, and using fluorescence polarization and isothermal titration calorimetry to analyze interactions with TRIB1. We hope that applying these considerations can facilitate further understanding of TRIB1 function, specifically, and can be selectively applied to improve studies of other Tribbles proteins and pseudokinases more generally.


Assuntos
Diferenciação Celular
9.
Methods Enzymol ; 667: 79-99, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35525562

RESUMO

Human Tribbles 2 (TRIB2) is a cancer-associated pseudokinase with a broad human protein interactome, including the well-studied AKT, C/EBPα and MAPK modules. Several lines of evidence indicate that human TRIB2 promotes cell survival and drug-resistance in solid tumors and blood cancers and is therefore of interest as a potential therapeutic target, although its physiological functions remain relatively poorly understood. The unique TRIB2 pseudokinase domain lacks the canonical 'DFG' motif, and subsequently possesses very low affinity for ATP in both the presence and absence of metal ions. However, TRIB2 also contains a unique cysteine-rich αC-helix, which interacts with a conserved peptide motif in its own carboxyl-terminal tail. This regulatory flanking region drives regulated interactions with distinct E3 ubiquitin ligases that serve to control the stability and turnover of TRIB2 client proteins. TRIB2 is also a low-affinity target of several known small-molecule protein kinase inhibitors, which were originally identified using purified recombinant TRIB2 proteins and a thermal shift assay. In this chapter, we discuss laboratory-based procedures for purification, stabilization and analysis of human TRIB2, including screening procedures that can be used for the identification of both reversible and covalent small molecule ligands.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina , Neoplasias , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias/patologia , Ubiquitina-Proteína Ligases/metabolismo
11.
J Biol Chem ; 298(2): 101556, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34973338

RESUMO

Enzalutamide, a second-generation antiandrogen, is commonly prescribed for the therapy of advanced prostate cancer, but enzalutamide-resistant, lethal, or incurable disease invariably develops. To understand the molecular mechanism(s) behind enzalutamide resistance, here, we comprehensively analyzed a range of prostate tumors and clinically relevant models by gene expression array, immunohistochemistry, and Western blot, which revealed that enzalutamide-resistant prostate cancer cells and tumors overexpress the pseudokinase, Tribbles 2 (TRIB2). Inhibition of TRIB2 decreases the viability of enzalutamide-resistant prostate cancer cells, suggesting a critical role of TRIB2 in these cells. Moreover, the overexpression of TRIB2 confers resistance in prostate cancer cells to clinically relevant doses of enzalutamide, and this resistance is lost upon inhibition of TRIB2. Interestingly, we found that TRIB2 downregulates the luminal markers androgen receptor and cytokeratin 8 in prostate cancer cells but upregulates the neuronal transcription factor BRN2 (Brain-2) and the stemness factor SOX2 (SRY-box 2) to induce neuroendocrine characteristics. Finally, we show that inhibition of either TRIB2 or its downstream targets, BRN2 or SOX2, resensitizes resistant prostate cancer cells to enzalutamide. Thus, TRIB2 emerges as a potential new regulator of transdifferentiation that confers enzalutamide resistance in prostate cancer cells via a mechanism involving increased cellular plasticity and lineage switching.


Assuntos
Benzamidas , Proteínas Quinases Dependentes de Cálcio-Calmodulina , Nitrilas , Feniltioidantoína , Neoplasias da Próstata , Benzamidas/farmacologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linhagem Celular Tumoral , Linhagem da Célula , Plasticidade Celular , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Nitrilas/farmacologia , Feniltioidantoína/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
12.
Proteins ; 90(4): 993-1004, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34881468

RESUMO

Tribbles pseudokinases, Tribbles homolog 1 (TRIB1), Tribbles homolog 2 (TRIB2), and Tribbles homolog 3 (TRIB3), bind to constitutive photomorphogenesis protein 1 (COP1) E3 ligase to mediate the regulation of ß-catenin expression. The interaction mechanism between COP1 E3 ligase and ß-catenin has not been addressed to date. Based on the functional presence of TRIBs in wingless-related integration site (WNT) signaling, we analyzed their interaction patterns with ß-catenin and COP1. Here, through in silico approaches, we ascribe the COP1 binding pattern against TRIBs and ß-catenin. TRIB1 (355-DQIVPEY-361), TRIB2 (326-DQLVPDV-332), and TRIB3 (333-AQVVPDG-339) peptides revealed a shallow binding pocket at the COP1 interface to accommodate the V-P sequence motif. Reinvigoration of the comparative binding pattern and subtle structural analysis via docking, molecular dynamics simulations, molecular mechanics Poisson-Boltzmann surface area, topological, and tunnel analysis revealed that both ß-catenin phosphodegron (DSGXXS) and TRIB (D/E/AQXVPD/E) motifs occupied a common COP1 binding site. Current study suggests a structural paradigm of TRIB homologs bearing a conserved motif that may compete with ß-catenin phosphodegron signature for binding to WD40 domain of COP1. Thorough understanding of the structural basis for TRIB-mediated regulation of WNT/ß-catenin signaling may help in devising more promising therapeutic strategy for liver and colorectal cancers.


Assuntos
Ubiquitina-Proteína Ligases , beta Catenina , Sítios de Ligação , Simulação de Dinâmica Molecular , Transdução de Sinais , Ubiquitina-Proteína Ligases/química , beta Catenina/genética , beta Catenina/metabolismo
13.
Front Oncol ; 11: 733175, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34646775

RESUMO

RFWD2, an E3 ubiquitin ligase, is overexpressed in numerous human cancers, including leukemia, lung cancer, breast cancer, renal cell carcinoma, and colorectal cancer. The roles of RFWD2 in cancer are related to the targeting of its substrates for ubiquitination and degradation. This study aimed to investigate the role of TRIB2 in relation to the regulation of protein degradation through RFWD2. inBio Discover™ results demonstrated that TRIB2 can perform its functions by interacting with RFWD2 or other factors. TRIB2 can interact with and regulate RFWD2, which further attends the proteasome-mediated degradation of the RFWD2 substrate p-IκB-α. TRIB2 colocalizes with RFWD2-related IκB-α to form a ternary complex and further affects the IκB-α degradation by regulating its phosphorylation. Specific domain analysis showed that TRIB2 may bind to RFWD2 via its C-terminus, whereas it binds to IκB via its pseudokinase domain. TRIB2 acts as an oncogene and promotes cancer cell proliferation and migration, whereas RFWD2 knockdown reversed the role of TRIB2 in promoting cancer cell growth and colony formation in vitro and in vivo. In summary, this study reveals that TRIB2 promotes the progression of cancer by affecting the proteasome-mediated degradation of proteins through the interaction with RFWD2.

14.
Cancers (Basel) ; 13(12)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205360

RESUMO

The Tribbles family of proteins-comprising TRIB1, TRIB2, TRIB3 and more distantly related STK40-play important, but distinct, roles in differentiation, development and oncogenesis. Of the four Tribbles proteins, TRIB1 has been most well characterised structurally and plays roles in diverse cancer types. The most well-understood role of TRIB1 is in acute myeloid leukaemia, where it can regulate C/EBP transcription factors and kinase pathways. Structure-function studies have uncovered conformational switching of TRIB1 from an inactive to an active state when it binds to C/EBPα. This conformational switching is centred on the active site of TRIB1, which appears to be accessible to small-molecule inhibitors in spite of its inability to bind ATP. Beyond myeloid neoplasms, TRIB1 plays diverse roles in signalling pathways with well-established roles in tumour progression. Thus, TRIB1 can affect both development and chemoresistance in leukaemia; glioma; and breast, lung and prostate cancers. The pervasive roles of TRIB1 and other Tribbles proteins across breast, prostate, lung and other cancer types, combined with small-molecule susceptibility shown by mechanistic studies, suggests an exciting potential for Tribbles as direct targets of small molecules or biomarkers to predict treatment response.

15.
Cancers (Basel) ; 13(11)2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34070799

RESUMO

The Tribbles pseudokinases family consists of TRIB1, TRIB2, TRIB3 and STK40 and, although evolutionarily conserved, they have distinctive characteristics. Tribbles members are expressed in a context and cell compartment-dependent manner. For example, TRIB1 and TRIB2 have potent oncogenic activities in vertebrate cells. Since the identification of Tribbles proteins as modulators of multiple signalling pathways, recent studies have linked their expression with several pathologies, including cancer. Tribbles proteins act as protein adaptors involved in the ubiquitin-proteasome degradation system, as they bridge the gap between substrates and E3 ligases. Between TRIB family members, TRIB2 is the most ancestral member of the family. TRIB2 is involved in protein homeostasis regulation of C/EBPα, ß-catenin and TCF4. On the other hand, TRIB2 interacts with MAPKK, AKT and NFkB proteins, involved in cell survival, proliferation and immune response. Here, we review the characteristic features of TRIB2 structure and signalling and its role in many cancer subtypes with an emphasis on TRIB2 function in therapy resistance in melanoma, leukemia and glioblastoma. The strong evidence between TRIB2 expression and chemoresistance provides an attractive opportunity for targeting TRIB2.

16.
Diagn Pathol ; 16(1): 47, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34030715

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the third normal malignancy worldwide. Taurine-upregulated gene 1 (TUG1), a member of long noncoding RNAs (lncRNAs), has been reported to be involved in various cancers. However, the mechanism underlying TUG1 in the progression of CRC remains unclear. METHODS: The expression of TUG1, microRNA-542-3p (miR-542-3p), and tribbles homolog 2 (TRIB2) in CRC tissues and cells (LoVo and HCT116) were detected by quantitative real-time PCR (qRT-PCR). Methyl thiazolyl tetrazolium (MTT), transwell and flow cytometry assays were employed to evaluate the effects of TUG1 in CRC cells. The interaction between miR-542-3p and TUG1 or TRIB2 were verified by dual-luciferase reporter assay. A xenograft tumor model in nude mice was established to investigate the biological role of TUG1 in CRC in vivo. RESULTS: TUG1 was increased in CRC tissues and cells (LoVo and HCT116) in contrast with adjacent normal tissues and normal intestinal mucous cells (CCC-HIE-2). Downregulation of TUG1 or TRIB2 suppressed the proliferation, migration, invasion, and induced apoptosis in CRC cells. And knockdown of TUG1 repressed tumor growth in vivo. Besides, overexpression of TRIB2 reversed the effects of TUG1 depletion on the progression of CRC. Meanwhile, TUG1 interacted with miR-542-3p and TRIB2 was a target of miR-542-3p. Furthermore, miR-542-3p knockdown or TRIB2 overexpression partly reversed the suppression effect of TUG1 depletion on the Wnt/ß-catenin pathway. CONCLUSIONS: TUG1 served as a tumor promoter, impeded the progression of CRC by miR-542-3p/TRIB2 axis to inactivate of Wnt/ß-catenin pathway, which providing a novel target for CRC treatment.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Neoplasias Colorretais/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Via de Sinalização Wnt , Animais , Apoptose , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Masculino , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA Longo não Codificante/genética , Carga Tumoral
17.
Int J Mol Sci ; 22(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546420

RESUMO

Members of the Tribbles (TRIB) family of pseudokinases are critical components of intracellular signal transduction pathways in physiological and pathological processes. TRIBs, including TRIB2, have been previously shown as signaling mediators and scaffolding proteins regulating numerous cellular events such as proliferation, differentiation and cell death through protein stability and activity. However, the signaling network associated with TRIB2 and its binding partners in granulosa cells during ovarian follicular development is not fully defined. We previously reported that TRIB2 is differentially expressed in growing dominant follicles while downregulated in ovulatory follicles following the luteinizing hormone (LH) surge or human chorionic gonadotropin (hCG) injection. In the present study, we used the yeast two-hybrid screening system and in vitro coimmunoprecipitation assays to identify and confirm TRIB2 interactions in granulosa cells (GCs) of dominant ovarian follicles (DFs), which yielded individual candidate binding partners including calmodulin 1 (CALM1), inhibin subunit beta A (INHBA), inositol polyphosphate phosphatase-like 1 (INPPL1), 5'-nucleotidase ecto (NT5E), stearoyl-CoA desaturase (SCD), succinate dehydrogenase complex iron sulfur subunit B (SDHB) and Ras-associated protein 14 (RAB14). Further analyses showed that all TRIB2 binding partners are expressed in GCs of dominant follicles but are differentially regulated throughout the different stages of follicular development. CRISPR/Cas9-driven inhibition along with pQE-driven overexpression of TRIB2 showed that TRIB2 differently regulates expression of binding partners, which reveals the importance of TRIB2 in the control of gene expression linked to various biological processes such as proliferation, differentiation, cell migration, apoptosis, calcium signaling and metabolism. These data provide a larger view of potential TRIB2-regulated signal transduction pathways in GCs and provide strong evidence that TRIB2 may act as a regulator of target genes during ovarian follicular development.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica , Células da Granulosa/metabolismo , Animais , Biomarcadores , Bovinos , Regulação para Baixo , Feminino , Folículo Ovariano/metabolismo , Ligação Proteica , Mapeamento de Interação de Proteínas , Técnicas do Sistema de Duplo-Híbrido
18.
Adv Biol Regul ; 79: 100777, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33451972

RESUMO

OCT4 (also known as Oct3 and Oct3/4), which is encoded by Pou5f1, is expressed in early embryonic cells and plays an important role in early development, pluripotency maintenance, and self-renewal of embryonic stem cells. It also regulates the reprogramming of somatic cells into induced pluripotent stem cells. Several OCT4-binding proteins, including SOX2 and NANOG, reportedly regulate gene transcription in stem cells. An increasing number of evidence suggests that not only gene transcription but also post-translational modifications of OCT4 play a pivotal role in regulating the expression and activity of OCT4. For instance, ubiquitination and sumoylation have been reported to regulate OCT4 protein stability. In addition, the phosphorylation of Ser347 in OCT4 also stabilizes the OCT4 protein level. Recently, we identified KAP1 as an OCT4-binding protein and reported the KAP1-mediated regulation of OCT4 protein stability. KAP1 overexpression led to an increased proliferation of mouse embryonic stem cells and promoted the reprogramming of somatic cells resulting in induced pluripotent stem cells. In this review, we discuss how the protein stability and function of OCT4 are regulated by protein-protein interaction in stem cells.


Assuntos
Células-Tronco Embrionárias/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 3 de Transcrição de Octâmero/química , Fator 3 de Transcrição de Octâmero/genética , Animais , Células-Tronco Embrionárias/química , Regulação da Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/química , Fator 3 de Transcrição de Octâmero/metabolismo , Ligação Proteica , Estabilidade Proteica , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
19.
Liver Int ; 41(5): 1131-1147, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33386706

RESUMO

BACKGROUND & AIMS: Hepatic stellate cells (HSCs) play critical roles in liver fibrosis and hepatocellular carcinoma (HCC). Tribbles homolog 2 (TRIB2) is an oncogene implicated in a variety of cancers, including liver cancer. However, the biological function and regulatory mechanism of TRIB2 in HSCs are poorly understood. In addition, little is known about its role in liver fibrosis progression to HCC. Here, we revealed the clinical significance of TRIB2 in liver fibrosis and HCC development. METHODS: We investigated TRIB2 promoting liver fibrosis in vitro and in vivo. In mouse model of liver fibrosis and HCC, we measured hepatic fibrosis and HCC level through knockdown TRIB2 with shRNA. In addition, we performed western blotting, real-time quantitative PCR, immunofluorescence and co-immunoprecipitation assay to study TRIB2 function in LX-2 cells. RESULTS: TRIB2 expression was strongly upregulated in human fibrotic liver tissues and HCC tissues. TRIB2 colocalized with α-smooth muscle actin (α-SMA) in fibrotic and HCC liver tissues. Knockdown of TRIB2 inhibited HSC activation and liver fibrosis in vitro and in vivo. TRIB2 promoted Yes-associated protein (YAP) stabilization, nuclear localization, and subsequent fibrotic gene expression independent of the MST-LATS phosphorylation cascade in HSCs. TRIB2 interacted with YAP to recruit phosphatase 1A (PP1A), promoting PP1A-mediated YAP dephosphorylation. TRIB2 knockdown potently attenuated the development of fibrosis-associated liver cancer. CONCLUSIONS: TRIB2 is an attractive target for hepatic fibrosis and fibrosis-associated liver cancer treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Quinases Dependentes de Cálcio-Calmodulina , Carcinoma Hepatocelular/patologia , Células Estreladas do Fígado/patologia , Humanos , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Monoéster Fosfórico Hidrolases
20.
Chinese Pharmacological Bulletin ; (12): 118-124, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1014302

RESUMO

Aim To investigate the effects of Evodiamine (EVO) on proliferation and apoptosis of human leukemia cell line K562 and its potential mechanisms. Methods K562 cells were treated with EVO at different concentrations (0, 1, 2, 4, 8, 16, 32, 64 jxmol • L

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