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1.
Cell ; 182(3): 578-593.e19, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32679029

RESUMO

Piloerection (goosebumps) requires concerted actions of the hair follicle, the arrector pili muscle (APM), and the sympathetic nerve, providing a model to study interactions across epithelium, mesenchyme, and nerves. Here, we show that APMs and sympathetic nerves form a dual-component niche to modulate hair follicle stem cell (HFSC) activity. Sympathetic nerves form synapse-like structures with HFSCs and regulate HFSCs through norepinephrine, whereas APMs maintain sympathetic innervation to HFSCs. Without norepinephrine signaling, HFSCs enter deep quiescence by down-regulating the cell cycle and metabolism while up-regulating quiescence regulators Foxp1 and Fgf18. During development, HFSC progeny secretes Sonic Hedgehog (SHH) to direct the formation of this APM-sympathetic nerve niche, which in turn controls hair follicle regeneration in adults. Our results reveal a reciprocal interdependence between a regenerative tissue and its niche at different stages and demonstrate sympathetic nerves can modulate stem cells through synapse-like connections and neurotransmitters to couple tissue production with demands.


Assuntos
Nervo Acessório/fisiologia , Folículo Piloso/citologia , Cabelo/crescimento & desenvolvimento , Proteínas Hedgehog/metabolismo , Norepinefrina/metabolismo , Transdução de Sinais/genética , Células-Tronco/metabolismo , Células-Tronco/fisiologia , Nervo Acessório/citologia , Animais , Ciclo Celular/genética , Temperatura Baixa , Feminino , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Cabelo/citologia , Cabelo/fisiologia , Folículo Piloso/crescimento & desenvolvimento , Folículo Piloso/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Piloereção , RNA-Seq , Receptores Adrenérgicos beta 2/deficiência , Receptores Adrenérgicos beta 2/genética , Receptores Adrenérgicos beta 2/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor Smoothened/genética , Receptor Smoothened/metabolismo , Nicho de Células-Tronco , Células-Tronco/citologia , Sistema Nervoso Simpático/citologia , Sistema Nervoso Simpático/fisiologia , Sinapses/fisiologia
2.
Blood ; 143(11): 996-1005, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-37992230

RESUMO

ABSTRACT: Genomic instability contributes to cancer progression and is at least partly due to dysregulated homologous recombination (HR). Here, we show that an elevated level of ABL1 kinase overactivates the HR pathway and causes genomic instability in multiple myeloma (MM) cells. Inhibiting ABL1 with either short hairpin RNA or a pharmacological inhibitor (nilotinib) inhibits HR activity, reduces genomic instability, and slows MM cell growth. Moreover, inhibiting ABL1 reduces the HR activity and genomic instability caused by melphalan, a chemotherapeutic agent used in MM treatment, and increases melphalan's efficacy and cytotoxicity in vivo in a subcutaneous tumor model. In these tumors, nilotinib inhibits endogenous as well as melphalan-induced HR activity. These data demonstrate that inhibiting ABL1 using the clinically approved drug nilotinib reduces MM cell growth, reduces genomic instability in live cell fraction, increases the cytotoxicity of melphalan (and similar chemotherapeutic agents), and can potentially prevent or delay progression in patients with MM.


Assuntos
Antineoplásicos , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Melfalan/farmacologia , Instabilidade Genômica , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
3.
Blood ; 141(21): 2599-2614, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-36630605

RESUMO

PSMD4/Rpn10 is a subunit of the 19S proteasome unit that is involved with feeding target proteins into the catalytic machinery of the 26S proteasome. Because proteasome inhibition is a common therapeutic strategy in multiple myeloma (MM), we investigated Rpn10 and found that it is highly expressed in MM cells compared with normal plasma cells. Rpn10 levels inversely correlated with overall survival in patients with MM. Inducible knockout or knockdown of Rpn10 decreased MM cell viability both in vitro and in vivo by triggering the accumulation of polyubiquitinated proteins, cell cycle arrest, and apoptosis associated with the activation of caspases and unfolded protein response-related pathways. Proteomic analysis revealed that inhibiting Rpn10 increased autophagy, antigen presentation, and the activation of CD4+ T and natural killer cells. We developed an in vitro AlphaScreen binding assay for high-throughput screening and identified a novel Rpn10 inhibitor, SB699551 (SB). Treating MM cell lines, leukemic cell lines, and primary cells from patients with MM with SB decreased cell viability without affecting the viability of normal peripheral blood mononuclear cells. SB inhibited the proliferation of MM cells even in the presence of the tumor-promoting bone marrow milieu and overcame proteasome inhibitor (PI) resistance without blocking the 20S proteasome catalytic function or the 19S deubiquitinating activity. Rpn10 blockade by SB triggered MM cell death via similar pathways as the genetic strategy. In MM xenograft models, SB was well tolerated, inhibited tumor growth, and prolonged survival. Our data suggest that inhibiting Rpn10 will enhance cytotoxicity and overcome PI resistance in MM, providing the basis for further optimization studies of Rpn10 inhibitors for clinical application.


Assuntos
Mieloma Múltiplo , Complexo de Endopeptidases do Proteassoma , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Proteômica , Leucócitos Mononucleares/metabolismo , Proteínas de Transporte/genética , Proteínas/metabolismo , Proteínas de Ligação a RNA
4.
Blood ; 141(4): 391-405, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36126301

RESUMO

Long noncoding RNAs (lncRNAs) can drive tumorigenesis and are susceptible to therapeutic intervention. Here, we used a large-scale CRISPR interference viability screen to interrogate cell-growth dependency to lncRNA genes in multiple myeloma (MM) and identified a prominent role for the miR-17-92 cluster host gene (MIR17HG). We show that an MIR17HG-derived lncRNA, named lnc-17-92, is the main mediator of cell-growth dependency acting in a microRNA- and DROSHA-independent manner. Lnc-17-92 provides a chromatin scaffold for the functional interaction between c-MYC and WDR82, thus promoting the expression of ACACA, which encodes the rate-limiting enzyme of de novo lipogenesis acetyl-coA carboxylase 1. Targeting MIR17HG pre-RNA with clinically applicable antisense molecules disrupts the transcriptional and functional activities of lnc-17-92, causing potent antitumor effects both in vitro and in vivo in 3 preclinical animal models, including a clinically relevant patient-derived xenograft NSG mouse model. This study establishes a novel oncogenic function of MIR17HG and provides potent inhibitors for translation to clinical trials.


Assuntos
MicroRNAs , Mieloma Múltiplo , RNA Longo não Codificante , Humanos , Animais , Camundongos , RNA Longo não Codificante/genética , Mieloma Múltiplo/genética , Cromatina , MicroRNAs/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica
5.
PLoS Genet ; 18(1): e1009952, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35051171

RESUMO

Overweight and obese are risk factors for various diseases. In Taiwan, the combined prevalence of overweight and obesity has increased dramatically. Here, we conducted a genome-wide association study (GWAS) on four adiposity traits, including body-mass index (BMI), body fat percentage (BF%), waist circumference (WC), and waist-hip ratio (WHR), using the data for more than 21,000 subjects in Taiwan Biobank. Associations were evaluated between 6,546,460 single-nucleotide polymorphisms (SNPs) and adiposity traits, yielding 13 genome-wide significant (GWS) adiposity-associated trait-loci pairs. A known gene, FTO, as well as two BF%-associated loci (GNPDA2-GABRG1 [4p12] and RNU6-2-PIAS1 [15q23]) were identified as pleiotropic effects. Moreover, RALGAPA1 was found as a specific genetic predisposing factor to high BMI in a Taiwanese population. Compared to other populations, a slightly lower heritability of the four adiposity traits was found in our cohort. Surprisingly, we uncovered the importance of neural pathways that might influence BF%, WC and WHR in the Taiwanese (East Asian) population. Additionally, a moderate genetic correlation between the WHR and BMI (γg = 0.52; p = 2.37×10-9) was detected, suggesting different genetic determinants exist for abdominal adiposity and overall adiposity. In conclusion, the obesity-related genetic loci identified here provide new insights into the genetic underpinnings of adiposity in the Taiwanese population.


Assuntos
Adiposidade/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Adulto , Bancos de Espécimes Biológicos , Estudos de Coortes , Feminino , Proteínas Ativadoras de GTPase/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Obesidade/genética , Sobrepeso/genética , Polimorfismo de Nucleotídeo Único , Taiwan
6.
Am J Physiol Cell Physiol ; 326(4): C1262-C1271, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38497111

RESUMO

Defining the oxygen level that induces cell death within 3-D tissues is vital for understanding tissue hypoxia; however, obtaining accurate measurements has been technically challenging. In this study, we introduce a noninvasive, high-throughput methodology to quantify critical survival partial oxygen pressure (pO2) with high spatial resolution within spheroids by using a combination of controlled hypoxic conditions, semiautomated live/dead cell imaging, and computational oxygen modeling. The oxygen-permeable, micropyramid patterned culture plates created a precisely controlled oxygen condition around the individual spheroid. Live/dead cell imaging provided the geometric information of the live/dead boundary within spheroids. Finally, computational oxygen modeling calculated the pO2 at the live/dead boundary within spheroids. As proof of concept, we determined the critical survival pO2 in two types of spheroids: isolated primary pancreatic islets and tumor-derived pseudoislets (2.43 ± 0.08 vs. 0.84 ± 0.04 mmHg), indicating higher hypoxia tolerance in pseudoislets due to their tumorigenic origin. We also applied this method for evaluating graft survival in cell transplantations for diabetes therapy, where hypoxia is a critical barrier to successful transplantation outcomes; thus, designing oxygenation strategies is required. Based on the elucidated critical survival pO2, 100% viability could be maintained in a typically sized primary islet under the tissue pO2 above 14.5 mmHg. This work presents a valuable tool that is potentially instrumental for fundamental hypoxia research. It offers insights into physiological responses to hypoxia among different cell types and may refine translational research in cell therapies.NEW & NOTEWORTHY Our study introduces an innovative combinatory approach for noninvasively determining the critical survival oxygen level of cells within small cell spheroids, which replicates a 3-D tissue environment, by seamlessly integrating three pivotal techniques: cell death induction under controlled oxygen conditions, semiautomated imaging that precisely identifies live/dead cells, and computational modeling of oxygen distribution. Notably, our method ensures high-throughput analysis applicable to various cell types, offering a versatile solution for researchers in diverse fields.


Assuntos
Ilhotas Pancreáticas , Oxigênio , Humanos , Oxigênio/metabolismo , Hipóxia/metabolismo , Ilhotas Pancreáticas/metabolismo , Esferoides Celulares/metabolismo , Hipóxia Celular , Sobrevivência Celular
7.
Gastroenterology ; 165(2): 357-373, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37178737

RESUMO

BACKGROUND & AIMS: The purpose of this study was to identify drivers of genomic evolution in esophageal adenocarcinoma (EAC) and other solid tumors. METHODS: An integrated genomics strategy was used to identify deoxyribonucleases correlating with genomic instability (as assessed from total copy number events in each patient) in 6 cancers. Apurinic/apyrimidinic nuclease 1 (APE1), identified as the top gene in functional screens, was either suppressed in cancer cell lines or overexpressed in normal esophageal cells and the impact on genome stability and growth was monitored in vitro and in vivo. The impact on DNA and chromosomal instability was monitored using multiple approaches, including investigation of micronuclei, acquisition of single nucleotide polymorphisms, whole genome sequencing, and/or multicolor fluorescence in situ hybridization. RESULTS: Expression of 4 deoxyribonucleases correlated with genomic instability in 6 human cancers. Functional screens of these genes identified APE1 as the top candidate for further evaluation. APE1 suppression in EAC, breast, lung, and prostate cancer cell lines caused cell cycle arrest; impaired growth and increased cytotoxicity of cisplatin in all cell lines and types and in a mouse model of EAC; and inhibition of homologous recombination and spontaneous and chemotherapy-induced genomic instability. APE1 overexpression in normal cells caused a massive chromosomal instability, leading to their oncogenic transformation. Evaluation of these cells by means of whole genome sequencing demonstrated the acquisition of changes throughout the genome and identified homologous recombination as the top mutational process. CONCLUSIONS: Elevated APE1 dysregulates homologous recombination and cell cycle, contributing to genomic instability, tumorigenesis, and chemoresistance, and its inhibitors have the potential to target these processes in EAC and possibly other cancers.


Assuntos
Adenocarcinoma , Resistencia a Medicamentos Antineoplásicos , Masculino , Animais , Camundongos , Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Hibridização in Situ Fluorescente , Linhagem Celular Tumoral , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Recombinação Homóloga , Ciclo Celular , Instabilidade Genômica , Genômica , Instabilidade Cromossômica/genética , Desoxirribonucleases/genética , Evolução Molecular
8.
Blood ; 139(16): 2471-2482, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35134130

RESUMO

The accessibility of cell surface proteins makes them tractable for targeting by cancer immunotherapy, but identifying suitable targets remains challenging. Here we describe plasma membrane profiling of primary human myeloma cells to identify an unprecedented number of cell surface proteins of a primary cancer. We used a novel approach to prioritize immunotherapy targets and identified a cell surface protein not previously implicated in myeloma, semaphorin-4A (SEMA4A). Using knock-down by short-hairpin RNA and CRISPR/nuclease-dead Cas9 (dCas9), we show that expression of SEMA4A is essential for normal myeloma cell growth in vitro, indicating that myeloma cells cannot downregulate the protein to avoid detection. We further show that SEMA4A would not be identified as a myeloma therapeutic target by standard CRISPR/Cas9 knockout screens because of exon skipping. Finally, we potently and selectively targeted SEMA4A with a novel antibody-drug conjugate in vitro and in vivo.


Assuntos
Mieloma Múltiplo , Semaforinas , Membrana Celular/metabolismo , Humanos , Fatores Imunológicos , Imunoterapia , Proteínas de Membrana , Mieloma Múltiplo/genética , Mieloma Múltiplo/terapia , Proteômica , Semaforinas/genética , Semaforinas/metabolismo
9.
Mol Biol Rep ; 51(1): 220, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281218

RESUMO

D-ribose, an ubiquitous pentose compound found in all living cells, serves as a vital constituent of numerous essential biomolecules, including RNA, nucleotides, and riboflavin. It plays a crucial role in various fundamental life processes. Within the cellular milieu, exogenously supplied D-ribose can undergo phosphorylation to yield ribose-5-phosphate (R-5-P). This R-5-P compound serves a dual purpose: it not only contributes to adenosine triphosphate (ATP) production through the nonoxidative phase of the pentose phosphate pathway (PPP) but also participates in nucleotide synthesis. Consequently, D-ribose is employed both as a therapeutic agent for enhancing cardiac function in heart failure patients and as a remedy for post-exercise fatigue. Nevertheless, recent clinical studies have suggested a potential link between D-ribose metabolic disturbances and type 2 diabetes mellitus (T2DM) along with its associated complications. Additionally, certain in vitro experiments have indicated that exogenous D-ribose exposure could trigger apoptosis in specific cell lines. This article comprehensively reviews the current advancements in D-ribose's digestion, absorption, transmembrane transport, intracellular metabolic pathways, impact on cellular behaviour, and elevated levels in diabetes mellitus. It also identifies areas requiring further investigation.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Doenças Metabólicas , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ribose/metabolismo , Trifosfato de Adenosina
10.
Cost Eff Resour Alloc ; 22(1): 53, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926787

RESUMO

Under the goal of sustainable development, coping with the increase in social security and healthcare expenses caused by population aging is becoming increasingly important, but it is rare in the literature to evaluate the impact of social security efficiency on healthcare efficiency. This research uses the dynamic SBM two-stage model to observe the efficiencies of social security and healthcare in OECD countries. There are two findings as follows. First, the higher social security efficiency is, the better is the healthcare efficiency of countries with lower per capita GDP. Second, higher social security efficiency of National Health Service (NHS) countries denote better healthcare efficiency. When the financial source of the social security system is taxation, then it is more likely to bring higher efficiency to healthcare.

11.
Nano Lett ; 23(22): 10490-10497, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37909686

RESUMO

The energy transfer (ET) between organic molecules and semiconductors is a crucial mechanism for enhancing the performance of semiconductor-based optoelectronic devices, but it remains undiscovered. Here, ultrafast optical pump-probe spectroscopy was utilized to directly reveal the ET between organic Alq3 molecules and Si semiconductors. Ultrathin SiO2 dielectric layers with a thickness of 3.2-10.8 nm were inserted between Alq3 and Si to prevent charge transfer. By means of the ET from Alq3 to Si, the SiO2 thickness-dependent relaxation dynamics of photoexcited carriers in Si have been unambiguously observed on the transient reflectivity change (ΔR/R) spectra, especially for the relaxation process on a time scale of 200-350 ps. In addition, these findings also agree with the results of our calculation in a model of long-range dipole-dipole interactions, which provides critical information for developing future optoelectronic devices.

12.
Blood Cells Mol Dis ; 99: 102725, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36682143

RESUMO

d-Ribose is not only an important component of some biomacromolecules, but also an active pentose with strong reducibility and non-enzymatic glycation ability. Previous studies reported the diverse role of d-ribose in different cells. In this study, the effects of d-ribose on non-enzymatic glycation of hemoglobin (Hb), as well as eryptosis, oxidative stress and energy metabolism of erythrocytes were observed by molecular fluorescence spectrophotometry, multi-wavelength spectrophotometry, high-pressure liquid chromatography (HPLC), mass spectrometry (MS) and flow cytometer. The results showed that d-ribose had the strongest non-enzymatic glycation ability to Hb in vitro when compared with other monosaccharides, and could enter the erythrocytes in a concentration-dependent manner, which was not inhibited by the specific glucose transporter 1 (GLUT1) inhibitor WZB117. In addition, d-ribose incubation increased the HbA1c, hemolysis, eryptosis, and ROS level of erythrocytes significantly more than that of d-glucose, however, no changes were observed in the levels of ATP, NADPH, and other intermediate energy metabolites in d-ribose treatment. Therefore, the strong non-enzymatic glycation ability of d-ribose may play an important role in erythrocyte damage.


Assuntos
Eriptose , Humanos , Ribose/química , Ribose/metabolismo , Ribose/farmacologia , Reação de Maillard , Eritrócitos/metabolismo , Estresse Oxidativo , Hemoglobinas/metabolismo , Metabolismo Energético , Cálcio/metabolismo , Fosfatidilserinas/metabolismo
13.
J Med Virol ; 95(11): e29233, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38009694

RESUMO

The COVID-19 pandemic emphasizes the significance of studying coronaviruses (CoVs). This study investigates the evolutionary patterns of 350 CoVs using four structural proteins (S, E, M, and N) and introduces a consensus methodology to construct a comprehensive phylogenomic network. Our clustering of CoVs into 4 genera is consistent with the current CoV classification. Additionally, we calculate network centrality measures to identify CoV strains with significant average weighted degree and betweenness centrality values, with a specific focus on RaTG13 in the beta genus and NGA/A116E7/2006 in the gamma genus. We compare the phylogenetics of CoVs using our distance-based approach and the character-based model with IQ-TREE. Both methods yield largely consistent outcomes, indicating the reliability of our consensus approach. However, it is worth mentioning that our consensus method achieves an approximate 5000-fold increase in speed compared to IQ-TREE when analyzing the data set of 350 CoVs. This improved efficiency enhances the feasibility of conducting large-scale phylogenomic studies on CoVs.


Assuntos
COVID-19 , Pandemias , Humanos , Filogenia , Consenso , Reprodutibilidade dos Testes
14.
Blood ; 137(17): 2360-2372, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33150374

RESUMO

Clonal evolution drives tumor progression, dissemination, and relapse in multiple myeloma (MM), with most patients dying of relapsed disease. This multistage process requires tumor cells to enter the circulation, extravasate, and colonize distant bone marrow (BM) sites. Here, we developed a fluorescent or DNA-barcode clone-tracking system on MM PrEDiCT (progression through evolution and dissemination of clonal tumor cells) xenograft mouse model to study clonal behavior within the BM microenvironment. We showed that only the few clones that successfully adapt to the BM microenvironment can enter the circulation and colonize distant BM sites. RNA sequencing of primary and distant-site MM tumor cells revealed a progression signature sequentially activated along human MM progression and significantly associated with overall survival when evaluated against patient data sets. A total of 28 genes were then computationally predicted to be master regulators (MRs) of MM progression. HMGA1 and PA2G4 were validated in vivo using CRISPR-Cas9 in the PrEDiCT model and were shown to be significantly depleted in distant BM sites, indicating their role in MM progression and dissemination. Loss of HMGA1 and PA2G4 also compromised the proliferation, migration, and adhesion abilities of MM cells in vitro. Overall, our model successfully recapitulates key characteristics of human MM disease progression and identified potential new therapeutic targets for MM.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais/metabolismo , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Proteína HMGA1a/metabolismo , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia/patologia , Proteínas de Ligação a RNA/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Medula Óssea/metabolismo , Medula Óssea/patologia , Sistemas CRISPR-Cas , Adesão Celular , Movimento Celular , Proliferação de Células , Evolução Clonal , Progressão da Doença , Feminino , Proteína HMGA1a/antagonistas & inibidores , Proteína HMGA1a/genética , Humanos , Camundongos , Camundongos SCID , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Prognóstico , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/genética , Taxa de Sobrevida , Células Tumorais Cultivadas
15.
Cell Commun Signal ; 21(1): 346, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38037039

RESUMO

In essence, the ß2 adrenergic receptor (ß2AR) plays an antiproliferative role by increasing the intracellular cyclic 3',5'-adenosine monophosphate (cAMP) concentration through Gαs coupling, but interestingly, ß2AR antagonists are able to effectively inhibit fibroblast-like synoviocytes (FLSs) proliferation, thus ameliorating experimental RA, indicating that the ß2AR signalling pathway is impaired in RA FLSs via unknown mechanisms. The local epinephrine (Epi) level was found to be much higher in inflammatory joints than in normal joints, and high-level stimulation with Epi or isoproterenol (ISO) directly promoted FLSs proliferation and migration due to impaired ß2AR signalling and cAMP production. By applying inhibitor of receptor internalization, and small interfering RNA (siRNA) of Gαs and Gαi, and by using fluorescence resonance energy transfer and coimmunoprecipitation assays, a switch in Gαs-Gαi coupling to ß2AR was observed in inflammatory FLSs as well as in FLSs with chronic ISO stimulation. This Gαi coupling was then revealed to be initiated by G protein coupled receptor kinase 2 (GRK2) but not ß-arrestin2 or protein kinase A-mediated phosphorylation of ß2AR. Inhibiting the activity of GRK2 with the novel GRK2 inhibitor paeoniflorin-6'-O-benzene sulfonate (CP-25), a derivative of paeoniflorin, or the accepted GRK2 inhibitor paroxetine effectively reversed the switch in Gαs-Gαi coupling to ß2AR during inflammation and restored the intracellular cAMP level in ISO-stimulated FLSs. As expected, CP-25 significantly inhibited the hyperplasia of FLSs in a collagen-induced arthritis (CIA) model (CIA FLSs) and normal FLSs stimulated with ISO and finally ameliorated CIA in rats. Together, our findings revealed the pathological changes in ß2AR signalling in CIA FLSs, determined the underlying mechanisms and identified the pharmacological target of the GRK2 inhibitor CP-25 in treating CIA. Video Abstract.


Assuntos
Artrite Experimental , Sinoviócitos , Animais , Ratos , Artrite Experimental/patologia , Proliferação de Células , Células Cultivadas , Epinefrina/metabolismo , Epinefrina/farmacologia , Epinefrina/uso terapêutico , Fibroblastos/metabolismo , Inflamação/metabolismo , Isoproterenol/metabolismo , Isoproterenol/farmacologia , Isoproterenol/uso terapêutico , Transdução de Sinais , Sinoviócitos/metabolismo , Sinoviócitos/patologia
16.
Cell Commun Signal ; 21(1): 172, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430297

RESUMO

BACKGROUND: Protein phosphatase 2A (PP2A) is one of the major protein phosphatases in eukaryotic cells and is essential for cellular homeostasis. PP2A is a heterotrimer comprising the dimeric AC core enzyme and a highly variable regulatory B subunit. Distinct B subunits help the core enzyme gain full activity toward specific substrates and contribute to diverse cellular roles of PP2A. PP2A has been thought to play a tumor suppressor and the B56γ3 regulatory subunit was shown to play a key tumor suppressor regulatory subunit of PP2A. Nevertheless, we uncovered a molecular mechanism of how B56γ3 may act as an oncogene in colorectal cancer (CRC). METHODS: Polyclonal pools of CRC cells with stable B56γ3 overexpression or knockdown were generated by retroviral or lentiviral infection and subsequent drug selection. Co-immunoprecipitation(co-IP) and in vitro pull-down analysis were applied to analyze the protein-protein interaction. Transwell migration and invasion assays were applied to investigate the role of B56γ3 in affecting motility and invasive capability of CRC cells. The sensitivity of CRC cells to 5-fluorouracil (5-FU) was analyzed using the PrestoBlue reagent assay for cell viability. Immunohistochemistry (IHC) was applied to investigate the expression levels of phospho-AKT and B56γ3 in paired tumor and normal tissue specimens of CRC. DataSets of TCGA and GEO were analyzed to investigate the correlation of B56γ3 expression with overall survival rates of CRC patients. RESULTS: We showed that B56γ3 promoted epithelial-mesenchymal transition (EMT) and reduced the sensitivity of CRC cells to 5-FU through upregulating AKT activity. Mechanistically, B56γ3 upregulates AKT activity by targeting PP2A to attenuate the p70S6K-mediated negative feedback loop regulation on PI3K/AKT activation. B56γ3 was highly expressed and positively correlated with the level of phospho-AKT in tumor tissues of CRC. Moreover, high B56γ3 expression is associated with poor prognosis of a subset of patients with CRC. CONCLUSIONS: Our finding reveals that the B56γ3 regulatory subunit-containing PP2A plays an oncogenic role in CRC cells by sustaining AKT activation through suppressing p70S6K activity and suggests that the interaction between B56γ3 and p70S6K may serve as a therapeutic target for CRC. Video Abstract.


Assuntos
Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Humanos , Proteína Fosfatase 2 , Proteínas Proto-Oncogênicas c-akt , Retroalimentação , Proteínas Quinases S6 Ribossômicas 70-kDa , Fosfatidilinositol 3-Quinases , Fluoruracila
17.
J Sci Food Agric ; 103(1): 450-456, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36205212

RESUMO

BACKGROUND: Nicotinamide mononucleotide (NMN), a key intermediate of nicotinamide adenine dinucleotide, plays an important in anti-aging and disease. Lactococcus lactis, an important probiotic lactic acid bacteria (LAB), has shown great potential for the biosynthesis of NMN, which will significantly affect the probiotic effects of the dairy products. RESULTS: We used the CRISPR/nCas9 technique to knockout nadR gene of L. lactis NZ9000 to enhance the accumulation of NMN by 61%. The nadE* gene from Francisella tularensis with codon optimization was heterologous in L. lactis NZ9000ΔnadR and has a positive effect on NMN production. Combined with optimization of the concentration of substrate nicotinamide, a final intracellular NMN titer was 2289 µmol L-1  mg-1 with 10 g L-1 nicotinamide supplement, which was 5.7-fold higher than that of the control. The transcription levels of key genes (pncA, nadD and prs1) involved in NMN biosynthesis were up-regulated by more than two-fold, indicating that the increase of NMN titer was attributed to FtnadE* heterologous expression. CONCLUSION: Our study provides a better understanding of the NMN biosynthesis pathway in L. lactis, and can facilitate NMN production in LAB via synthetic biology approaches. © 2022 Society of Chemical Industry.


Assuntos
Lactococcus lactis , Mononucleotídeo de Nicotinamida , Mononucleotídeo de Nicotinamida/metabolismo , Mononucleotídeo de Nicotinamida/farmacologia , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , NAD/metabolismo , Niacinamida/metabolismo
18.
BMC Genomics ; 22(Suppl 5): 921, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35681126

RESUMO

BACKGROUND: The collection of circRNAs mostly focused on their sequence composition such as protein/miRNA binding motif, and/or regulatory elements such as internal ribosome entry site. However, less attention was paid to subcellular localization. CircVIS aimed to provide a collection of circRNAs with information of subcellular compartments and also integrated the circRNA entries from previous circRNA databases. RESULTS: A collection of circRNAs from public circRNA databases and de novo identification were annotated according to subcellular localizations including nucleoplasm, chromatin-associated parts, cytoplasm and polyribosome. All circRNAs were aligned to a selected major transcript, and if presence, the circRNA-derived open reading frame with annotation of functional domain were compared to its parental protein. The results showed that distinct circRNAs may exert their molecular and cellular functions in different subcellular compartments. The web service is made freely available at http://lab-x-omics.nchu.edu.tw/circVIS . CONCLUSIONS: CircVIS allows users to visualize the alignment between a given circRNA and its most relevant reference transcript along with information of subcellular localization.


Assuntos
MicroRNAs , RNA Circular , Sítios Internos de Entrada Ribossomal , MicroRNAs/genética , Fases de Leitura Aberta , Proteínas/genética , RNA/metabolismo
19.
Curr Issues Mol Biol ; 44(5): 2107-2121, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35678671

RESUMO

Taraxacum officinale (dandelion) is often used in traditional Chinese medicine for the treatment of cancer; however, the downstream regulatory genes and signaling pathways mediating its effects on breast cancer remain unclear. The present study aimed to explore the effects of luteolin, the main biologically active compound of T. officinale, on gene expression profiles in MDA-MB-231 and MCF-7 breast cancer cells. The results revealed that luteolin effectively inhibited the proliferation and motility of the MDA-MB-231 and MCF-7 cells. The mRNA expression profiles were determined using gene expression array analysis and analyzed using a bioinformatics approach. A total of 41 differentially expressed genes (DEGs) were found in the luteolin-treated MDA-MB-231 and MCF-7 cells. A Gene Ontology analysis revealed that the DEGs, including AP2B1, APP, GPNMB and DLST, mainly functioned as oncogenes. The human protein atlas database also found that AP2B1, APP, GPNMB and DLST were highly expressed in breast cancer and that AP2B1 (cut-off value, 75%) was significantly associated with survival rate (p = 0.044). In addition, a Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the DEGs were involved in T-cell leukemia virus 1 infection and differentiation. On the whole, the findings of the present study provide a scientific basis that may be used to evaluate the potential benefits of luteolin in human breast cancer. Further studies are required, however, to fully elucidate the role of the related molecular pathways.

20.
Cancer Sci ; 113(12): 4151-4164, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36114745

RESUMO

Oncogene-derived metabolic reprogramming is important for anabolic growth of cancer cells, which is now considered to be not simply rely on glycolysis. Pentose phosphate pathway and tricarboxylic acid cycle also play pivotal roles in helping cancer cells to meet their anabolic and energy demands. The present work focused on gankyrin, a relatively specific oncogene in hepatocellular carcinoma (HCC), and its impact on glycolysis and mitochondrial homeostasis. Metabolomics, RNA-seq analysis, and subsequent conjoint analysis illustrated that gankyrin regulated the pentose phosphate pathway (PPP), tricarboxylic acid (TCA) cycle, and mitochondrial function and homeostasis, which play pivotal roles in tumor development. Mechanistically, gankyrin was found to modulate HCC metabolic reprogramming via TIGAR. Gankyrin positively regulated the transcription of TIGAR through Nrf2, which bound to the antioxidant response elements (AREs) in the promoter of TIGAR. Interestingly, TIGAR feedback regulated the transcription of Nrf2 and subsequently gankyrin by promoting nuclear importation of PGC1α. The loop between gankyrin, Nrf2, and TIGAR accelerated glucose metabolism toward the PPP and TCA cycle, which provided vital building blocks, such as NADPH, ATP, and ribose of tumor and further facilitated the progression of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Ciclo do Ácido Cítrico , Neoplasias Hepáticas/patologia , Glicólise , Glucose/metabolismo
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