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1.
Chem Soc Rev ; 53(10): 5149-5189, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38566609

RESUMO

The electrochemical reduction of CO2 into value-added chemicals has been explored as a promising solution to realize carbon neutrality and inhibit global warming. This involves utilizing the electrochemical CO2 reduction reaction (CO2RR) to produce a variety of single-carbon (C1) and multi-carbon (C2+) products. Additionally, the electrolyte solution in the CO2RR system can be enriched with nitrogen sources (such as NO3-, NO2-, N2, or NO) to enable the synthesis of organonitrogen compounds via C-N coupling reactions. However, the electrochemical conversion of CO2 into valuable chemicals still faces challenges in terms of low product yield, poor faradaic efficiency (FE), and unclear understanding of the reaction mechanism. This review summarizes the promising strategies aimed at achieving selective production of diverse carbon-containing products, including CO, formate, hydrocarbons, alcohols, and organonitrogen compounds. These approaches involve the rational design of electrocatalysts and the construction of coupled electrocatalytic reaction systems. Moreover, this review presents the underlying reaction mechanisms, identifies the existing challenges, and highlights the prospects of the electrosynthesis processes. The aim is to offer valuable insights and guidance for future research on the electrocatalytic conversion of CO2 into carbon-containing products of enhanced value-added potential.

2.
Int J Obes (Lond) ; 47(1): 67-74, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36396857

RESUMO

OBJECTIVES: The aim of this study was to investigate the relationship between body composition and leukocyte telomere length (LTL) in healthy Chinese children aged 6-11 years. METHODS: This cross-sectional study enrolled 406 healthy children (175 girls and 231 boys). The relative telomere length in their peripheral blood leukocytes was determined via quantitative polymerase chain reaction. Dual-energy X-ray absorptiometry was used to determine body fat content and regional fat distribution, appendicular skeletal muscle mass (ASM), bone mineral density (BMD) and bone mineral content (BMC) at the total body (TB) and total body less head (TBLH) levels, and total body lean mass (TBLM) was then determined. ASM/height2 (ASMI) was also calculated. RESULTS: After adjusting for potential covariates, multiple linear regression analyses revealed that neither body fat content nor regional body fat distribution were significantly associated with LTL (ß = -8.48 × 10-6-1.44 × 10-1, p = 0.227-0.959). However, ASM, ASMI, TB BMC/TB BMD, TBLH BMC/TBLH BMD and TBLM were positively associated with LTL (ß = 8.95 × 10-6-4.95 × 10-1, p = 0.005-0.035). Moreover, analysis of covariance revealed there was a statistically significant dose-dependent positive association between LTL and ASM, TB BMC/BMD, TBLH BMC/BMD, and TBLM (p-trend = 0.002-0.025). CONCLUSIONS: Skeletal muscle mass and bone mass but not body fat content or distribution were significantly associated with LTL in this pediatric population.


Assuntos
Composição Corporal , Densidade Óssea , Masculino , Feminino , Humanos , Criança , Estudos Transversais , Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Absorciometria de Fóton , Telômero
3.
J Nutr ; 152(6): 1549-1559, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35278080

RESUMO

BACKGROUND: Telomere length (TL) serves as a marker of cellular senescence and appears to plateau between the age of 4 y and young adulthood, after which the gut microbiota are supposed to be established. However, scarce data are available regarding the correlation between gut microbiota composition and TL in the pediatric population. OBJECTIVES: We aimed to investigate whether the gut microbiota and the concentrations of SCFAs in feces are associated with leukocyte TL in children. METHODS: In total, 401 children aged 6-9 y from Guangzhou were enrolled in this cross-sectional study. qPCR was used to determine relative TL in peripheral blood leukocytes. The gut microbiota was characterized by 16S ribosomal RNA amplicon sequencing and the fecal concentrations of total SCFAs and SCFA subtypes were determined using HPLC. The multivariate methods with an unbiased variable selection (MUVR) algorithm and partial least square models were used to select predictable operational taxonomic units (OTUs). Further correlation analyses were performed based on multiple linear regression models with adjustment for covariates and false discovery rate. RESULTS: With the use of MUVR, 35 relevant and minimal optimal OTUs were finally selected. Multiple linear regression analysis showed that the abundance of several OTUs, including OTU334 (belonging to the genus Family XIII AD3011 group), OTU726 (belonging to the species Lachnoclostridium phocaeense), OTU1441 (belonging to the genus Ruminococcus torques group), OTU2553 (belonging to the genus Lachnospiraceae UCG-010), and OTU3375 (belonging to the family Lachnospiraceae), was negatively associated with leukocyte TL (ß: -0.187 to -0.142; false discovery rate (FDR)-corrected P value (PFDR) = 0.009-0.035]. However, neither SCFA subtype nor total SCFA content in feces exhibited significant associations with TL (ß: -0.032 to 0.048; PFDR = 0.915-0.969). CONCLUSIONS: The gut microbiota, but not fecal SCFA concentration, was significantly associated with TL in this pediatric population.


Assuntos
Microbioma Gastrointestinal , Adulto , Criança , Estudos Transversais , Ácidos Graxos Voláteis/análise , Fezes/química , Microbioma Gastrointestinal/genética , Humanos , Leucócitos/química , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Telômero , Adulto Jovem
4.
Cancer Sci ; 111(5): 1761-1773, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32103527

RESUMO

The cyclin-dependent kinase (CDK)4/6-cyclin D1-Rb-p16/ink4a pathway is responsible for regulating cell progression past the G1 restriction point during the cell cycle. The development of a majority of human tumors is associated with dysregulation of this pathway, resulting in increased cancer cell proliferation. Both CDK4 and CDK6, well-validated cancer drug targets, function primarily as catalytic enzymes that mediate the phosphorylation of retinoblastoma protein (Rb). Here, we determined that SPH3643 is a novel potent antiproliferative agent that inhibits CDK4/6 kinase activity. In biochemical assays, SPH3643 showed more potent inhibition of both CDK4 and CDK6 than did 2 published CDK4/6 inhibitors, LY2835219 and palbociclib, and had better selectivity than LY2835219. Further in vitro study revealed that SPH3643 blocked Cdk/Rb signaling by inhibiting the phosphorylation of RbSer780 and arrested the MCF-7 cancer cells at G0 /G1 phase, resulting in marked inhibition of the proliferation of Rb-positive cancer cell lines. In vivo SPH3643 treatment in mice bearing xenograft tumor models of breast cancer, colon cancer, acute myelocytic leukemia, and glioblastoma resulted in significant decreases in tumor growth. SPH3643 was able to particularly strongly inhibit glioblastoma (U87-MG) cell growth in the brains of orthotopic carcinoma xenograft mice due to its high degree of intracerebral penetration and significant persistence in this setting. Together these results revealed that SPH3643 is a potent, orally active small-molecule inhibitor of CDK4/6 with robust anticancer efficacy and a high degree of blood-brain barrier permeability.


Assuntos
Antineoplásicos/farmacologia , Barreira Hematoencefálica/metabolismo , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Animais , Antineoplásicos/uso terapêutico , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/uso terapêutico , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Small ; 13(23)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28452410

RESUMO

A novel strategy for the fabrication of hollow Co and N-codoped carbon nanopolyhedra (H-CoNC) from metal-organic framework (MOF) using in situ evaporation of ZnO nanosphere templates is proposed. The excess Zn supply during the pyrolysis process is found beneficial in terms of high nitrogen (≈9.75 at%), relatively homogenous CoN bonding, and the electrochemically accessible hierarchical porous system. Compared with other reported "solid" CoNC of identical surface areas, the newly developed H-CoNC shows enhanced kinetic current in 0.1 m KOH electrolyte and elevated oxygen reduction reaction (ORR) performance in 6 m KOH. The latter exceeds results obtained with the benchmark 20 wt% Pt/C, which is related to the strong confinement of O2 molecules in the H-CoNC hierarchical porous system. Furthermore, the H-CoNC displays great tolerance toward the methanol crossover and KSCN poisoning. Finally, the assembled Zn-air batteries with H-CoNC yield a record open circuit potential (1.59 V vs Zn, stabilized at 1.52 V), high power density (331.0 mW cm-2 ), and promising rate performance. This work provides a new guideline for the design of MOF-derived carbon materials, as well as novel insights into spatial confinement effect toward the ORR activity.

6.
Acta Pharmacol Sin ; 38(7): 1038-1047, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28414200

RESUMO

Over half of patients with BRCA1-deficient cancers do not respond to treatment with poly(ADP-ribose) polymerase (PARP) inhibitors. In this study, we report that a combination of 53BP1 and BRCA1 may serve as a biomarker of PARP inhibitor sensitivity. Based on the mRNA levels of four homologous recombination repair (HR) genes and PARP inhibitor sensitivity, we selected BRCA1-deficient MDA-MB-436 cells to conduct RNA interference. Reducing expression of 53BP1, but not the other three HR genes, was found to lower simmiparib sensitivity. Additionally, we generated 53BP1-/-/BRCA1-/- clonal variants by the transcription activator-like effector nuclease (TALEN) technique and found that depleting 53BP1 impaired PARP inhibitor sensitivity with a 36.7-fold increase in their IC50 values. Consistent with its effect on PARP inhibitor sensitivity, 53BP1 loss alleviated cell cycle arrest and apoptosis and partially restored HR function. Importantly, 53BP1 depletion dramatically reduced the ability of PARP inhibitors to suppress tumor growth in vivo. The inhibition rate of simmiparib was 74.16% for BRCA1-deficient MDA-MB-436 xenografts, but only 7.79% for 53BP1/BRCA1-deficient xenografts. Re-expressing 53BP1 in the dual-deficient cells restored PARP inhibitor sensitivity and the levels of HR regulators. Considering that at least 10% of BRCA1-deficient breast and ovarian cancers have reduced expression of 53BP1, using a combination of 53BP1 with BRCA1 as a biomarker for patient selection should reduce the number of patients undergoing futile treatment with PARP inhibitors.


Assuntos
Antineoplásicos/farmacologia , Proteína BRCA1/antagonistas & inibidores , Biomarcadores Tumorais/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/antagonistas & inibidores , Animais , Antineoplásicos/química , Proteína BRCA1/deficiência , Proteína BRCA1/metabolismo , Biomarcadores Tumorais/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/química , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Relação Estrutura-Atividade , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/deficiência , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
7.
Hippocampus ; 24(5): 528-40, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24493406

RESUMO

Adult individuals with early stressful experience exhibit impaired hippocampal neuronal morphology, synaptic plasticity and cognitive performance. While our knowledge on the persistent effects of early-life stress on hippocampal structure and function and the underlying mechanisms has advanced over the recent years, the molecular basis of the immediate postnatal stress effects on hippocampal development remains to be investigated. Here, we reported that repeated blockade of corticotropin-releasing hormone receptor 1 (CRHR1) ameliorated postnatal stress-induced hippocampal synaptic abnormalities in neonatal mice. Following the stress exposure, pups with fragmented maternal care showed retarded dendritic outgrowth and spine formation in CA3 pyramidal neurons and reduced hippocampal levels of synapse-related proteins. During the stress exposure, repeated blockade of glucocorticoid receptors (GRs) by daily administration of RU486 (100 µg g(-1) ) failed to attenuate postnatal stress-evoked synaptic impairments. Conversely, daily administration of the CRHR1 antagonist antalarmin hydrochloride (20 µg g(-1) ) in stressed pups normalized hippocampal protein levels of synaptophysin, postsynaptic density-95, nectin-1, and nectin-3, but not the N-methyl-d-aspartate receptor subunits NR1 and NR2A. Additionally, GR or CRHR1 antagonism attenuated postnatal stress-induced endocrine alterations but not body growth retardation. Our data indicate that the CRH-CRHR1 system modulates the deleterious effects of early-life stress on dendritic development, spinogenesis, and synapse formation, and that early interventions of this system may prevent stress-induced hippocampal maldevelopment.


Assuntos
Hipocampo/patologia , Neurônios/metabolismo , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/patologia , Sinapses/patologia , Animais , Animais Recém-Nascidos , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular Neuronais/metabolismo , Corticosterona/sangue , Dendritos/patologia , Proteína 4 Homóloga a Disks-Large , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Guanilato Quinases/metabolismo , Antagonistas de Hormônios/farmacologia , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Mifepristona/farmacologia , Nectinas , Proteínas do Tecido Nervoso/metabolismo , Neurônios/patologia , Neurônios/ultraestrutura , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Estresse Psicológico/tratamento farmacológico , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Sinaptofisina/metabolismo
8.
J Hazard Mater ; 476: 134909, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38905979

RESUMO

Developing highly-efficient electrocatalysts for the nitrate reduction reaction (NITRR) is a persistent challenge. Here, we present the successful synthesis of 14 amorphous/low crystallinity metal nanofilms on three-dimensional carbon fibers (M-NFs/CP), including Al, Ti, Mn, Fe, Co, Ni, Cu, Zn, Ag, In, Sn, Pb, Au, or Bi, using rapid thermal evaporation. Among these samples, our study identifies the amorphous Co nanofilm with fine agglomerated Co clusters as the optimal electrocatalyst for NITRR in a neutral medium. The resulting Co-NFs/CP exhibits a remarkable Faradaic efficiency (FENH3) of 91.15 % at - 0.9 V vs RHE, surpassing commercial Co foil (39 %) and Co powder (20 %), despite sharing the same metal composition. Furthermore, during the electrochemical NITRR, the key intermediates on the surface of the Co-NFs/CP catalyst were detected by in situ Fourier-transform infrared (FTIR) spectroscopy, and the possible reaction ways were probed by Density functional theory (DFT) calculations. Theoretical calculations illustrate that the abundant low-coordinate Co atoms of Co-NFs/CP could enhances the adsorption of *NO3 intermediates compared to crystalline Co. Additionally, the amorphous Co structure lowers the energy barrier for the rate-determining step (*NH2→*NH3). This work opens a new avenue for the controllable synthesis of amorphous/low crystallinity metal nano-catalysts for various electrocatalysis reaction applications.

9.
Ann Med ; 55(2): 2279748, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37983519

RESUMO

The intricate web of cancer biology is governed by the active participation of long non-coding RNAs (lncRNAs), playing crucial roles in cancer cells' proliferation, migration, and drug resistance. Pioneering research driven by machine learning algorithms has unveiled the profound ability of specific combinations of lncRNAs to predict the prognosis of cancer patients. These findings highlight the transformative potential of lncRNAs as powerful therapeutic targets and prognostic markers. In this comprehensive review, we meticulously examined the landscape of lncRNAs in predicting the prognosis of the top five cancers and other malignancies, aiming to provide a compelling reference for future research endeavours. Leveraging the power of machine learning techniques, we explored the predictive capabilities of diverse lncRNA combinations, revealing their unprecedented potential to accurately determine patient outcomes.


lncRNAs play crucial roles in cancer biology, regulating proliferation, migration, and drug resistance.Emerging evidence suggests that machine learning can predict cancer prognosis using specific lncRNA combinations.Comprehensive information on the predictive abilities of lncRNA combinations in oncology concerning machine learning is lacking.This review offers up-to-date vital references on diverse lncRNA combinations pertinent to future research and clinical trials.


Assuntos
Neoplasias , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Neoplasias/diagnóstico , Neoplasias/genética , Prognóstico , Aprendizado de Máquina
10.
Toxicol Lett ; 367: 9-18, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35843418

RESUMO

Cadmium (Cd)-induced bone damage may be mediated through activating osteoclastogenesis. However, the underlying mechanism is unknown. The purpose of this study was to explore the effect and possible mechanism of CdCl2-induced osteoclastogenesis in RAW264.7 cells. We found that a low concentration of CdCl2 (0.025 and 0.050 µM) did not affect the viability of RAW264.7 cells, but promoted osteoclastogenesis. A low concentration of CdCl2 increased the mRNA and protein expression of osteoclastogenesis-related genes. TRAP staining and transmission electron microscopy (TEM) also demonstrated that CdCl2 promoted osteoclastogenesis. A low concentration of CdCl2 upregulated the levels of LC3-II and Beclin-1, and decreased p62 expression. TEM showed relatively abundant autophagic vacuoles (autophagosomes) after CdCl2 exposure. A low concentration of CdCl2 downregulated the expression levels of Mtor and p70S6K1, and the relative protein expression ratios of p-mTOR/mTOR and p-p70S6K1/p70S6K1. When cells were treated with the autophagy inhibitor chloroquine (CQ) or mTOR activator MHY1485 combined with CdCl2, the expressions of osteoclastogenesis related-genes were decreased and autophagy was attenuated compared with cells treated with CdCl2 alone. Deficiencies in autophagosomes and osteoclasts were also observed. Taken together, the results indicate that a low concentration of CdCl2 promotes osteoclastogenesis by enhancing autophagy via inhibiting the mTOR/p70S6K1 signaling pathway.


Assuntos
Cádmio , Osteogênese , Autofagia , Cádmio/toxicidade , Proteínas Quinases S6 Ribossômicas 70-kDa , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
11.
Nutrients ; 14(18)2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36145128

RESUMO

Early bone accrual significantly influences adult bone health and osteoporosis incidence. We aimed to investigate the relationship between dietary patterns (DPs), bone mineral content (BMC) and bone mineral density (BMD) in school-age children in China. Children aged six-nine years (n = 465) were enrolled in this cross-sectional study. DPs were identified by principal component factor analysis. Total body (TB) and total body less head (TBLH) BMC and BMD were measured using dual-energy X-ray absorptiometry. Five DPs were identified. After adjustment for covariates, multiple linear regression analysis showed that the "fruit-milk-eggs" dietary pattern was positively associated with TB (ß = 10.480; 95% CI: 2.190, 18.770) and TBLH (ß = 5.577; 95% CI: 0.214, 10.941) BMC, the "animal organs-refined cereals" pattern was associated with low TB BMC (ß = -10.305; 95% CI: -18.433, -2.176), TBLH BMC (ß = -6.346; 95% CI: -11.596, -1.096), TB BMD (ß = -0.006; 95% CI: -0.011, -0.001) and TBLH BMD (ß = -0.004; 95% CI: -0.007, -0.001). In conclusion, our study recommends home or school meals should be rich in fruit, milk, eggs with a moderate amount of vegetables, coarse grains and meat to promote bone development for school-age children.


Assuntos
Densidade Óssea , Dieta , Absorciometria de Fóton , Animais , Estudos Transversais , Humanos , Verduras
12.
Int J Cancer ; 129(10): 2527-31, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21213215

RESUMO

MicroRNAs (miRNAs) are noncoding RNAs that regulate gene expression by inhibiting translation or by promoting mRNA degradation. Previously, we established that microRNA-153 (miR-153) induces apoptosis by downregulating B-cell lymphoma 2 (Bcl-2) and myeloid cell leukemia sequence 1 (Mcl-1) protein expression levels in glioblastoma cell line DBTRG-05MG. In our study, we show that ectopic expression of miR-153 also inhibits the protein kinase B (PKB/Akt) pathway via reducing the protein level of insulin receptor substrate-2 (Irs-2). Moreover, simultaneous treatment with the chromatin-modifying drugs 4-phenylbutyric acid and 5-aza-2'-deoxycytidine induces miR-153 expression to suppress Irs-2, Bcl-2 and Mcl-1 expressions, thus downregulating the survival but upregulating the apoptotic pathways, implying that tumor suppressor miR-153 is a dual life and death regulator.


Assuntos
Glioblastoma/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , MicroRNAs/metabolismo , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Decitabina , Humanos , Fenilbutiratos/farmacologia
13.
Neuropsychiatr Dis Treat ; 17: 453-469, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603382

RESUMO

Metabolic syndrome (MetS) in patients with schizophrenia occurs 2-3 times more frequently than in the general population. Antipsychotic medication is a primary risk factor for patients with MetS. In particular, the widely used second-generation antipsychotics can affect glucose and lipid metabolism and can induce insulin resistance and other metabolic abnormalities through various receptors. Notably, the metabolic risks of various antipsychotics may differ because of their different pharmacological affinity to MetS-related receptors. Several previous studies have shown that switching from high to low metabolic risk antipsychotics may improve patients' metabolic parameters. The current review aims to discuss the strategies for switching antipsychotic medications and the impact on metabolic abnormalities in patients with schizophrenia.

14.
Int J Cancer ; 126(4): 1029-35, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19676043

RESUMO

MicroRNA-153 (miR-153) is a brain-specific miRNA that is expressed at a significantly lower level in glioblastoma (GBM) relative to non-neoplastic brain tissue. Although the expression pattern of miR-153 has been extensively established, its target genes and cellular mechanism remain undefined. To investigate into the potential function of miR-153 in glioblastmas, we transfected a GBM cell line DBTRG-05MG with synthetic miR-153 oligos and observed decreased cell proliferation and increased apoptosis. Bioinformatics analysis revealed that anti-apoptosis family member B-cell lymphoma 2 (Bcl-2) and myeloid cell leukemia sequence 1 (Mcl-1) are potential targets of miR-153. Indeed, Western blot analysis indicated that miR-153 downregulated both Bcl-2 and Mcl-1 at the protein levels. Single strand miR-153 inhibitor, which forms complementary base-pair with endogenous miR-153, efficiently blocked the apoptosis and target protein degradation induced by overexpression of miR-153. By luciferase reporter assays, we further showed that miR-153 inhibited Bcl-2 and Mcl-1 expressions by directly targeting the 3'UTR regions of their respective mRNAs.


Assuntos
Linfoma de Células B/patologia , MicroRNAs/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Regiões 3' não Traduzidas/genética , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Glioblastoma/patologia , Humanos , MicroRNAs/uso terapêutico , Proteína de Sequência 1 de Leucemia de Células Mieloides , Reação em Cadeia da Polimerase , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Transfecção/métodos
15.
Eur J Med Chem ; 193: 112239, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32200202

RESUMO

CDK4/6 has been identified as an attractive therapeutic target for treatment of cancer. For unmet clinical needs, a novel class of imidazo [1',2':1,6]pyrido [2,3-d]pyrimidin derivatives, which had distinctive triheteroaryl structure, had been discovered as CDK4/6 inhibitors. The compounds 10b and 10c, displayed the low nanomolar range activities on CDK4/6, desirable antiproliferative activities, excellent metabolic properties, and acceptable pharmacokinetic characters. In Colo-205 and U87MG xenograft models, compounds 10b and 10c also showed significant tumor growth inhibitions with controllable toxicities. All data confirmed that imidazo [1',2':1,6]pyrido [2,3-d]pyrimidin derivatives 10b and 10c could be promising drug candidates for cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Descoberta de Drogas , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirimidinas/síntese química , Pirimidinas/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Distribuição Tecidual
16.
Sci Transl Med ; 12(531)2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075946

RESUMO

MYCN-amplified neuroblastoma (NB) is characterized by poor prognosis, and directly targeting MYCN has proven challenging. Here, we showed that aldehyde dehydrogenase family 18 member A1 (ALDH18A1) exerts profound impacts on the proliferation, self-renewal, and tumorigenicity of NB cells and is a potential risk factor in patients with NB, especially those with MYCN amplification. Mechanistic studies revealed that ALDH18A1 could both transcriptionally and posttranscriptionally regulate MYCN expression, with MYCN reciprocally transactivating ALDH18A1 and thus forming a positive feedback loop. Using molecular docking and screening, we identified an ALDH18A1-specific inhibitor, YG1702, and demonstrated that pharmacological inhibition of ALDH18A1 was sufficient to induce a less proliferative phenotype and confer tumor regression and prolonged survival in NB xenograft models, providing therapeutic insights into the disruption of this reciprocal regulatory loop in MYCN-amplified NB.


Assuntos
Aldeído Desidrogenase/genética , Proteína Proto-Oncogênica N-Myc , Células-Tronco Neurais , Neuroblastoma , Linhagem Celular Tumoral , Retroalimentação , Humanos , Simulação de Acoplamento Molecular , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética
17.
Eur J Med Chem ; 178: 352-364, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31200237

RESUMO

Targeting CDK4/6 has been identified as an effective therapeutics for treatment of cancer. We herein reported the discovery of a series of 6-(2-(methylamino)ethyl)-5,6,7,8-tetrahydro-1,6-naphthyridin-2-amine derivatives as CDK4/6 inhibitors against cancer. Compound 3c, which displayed high potency and selectivity on CDK4/6 (IC50 = 0.710/1.10 nM) over a variety of other kinases, possessed desirable antiproliferative activities, excellent metabolic properties, and favorable pharmacokinetic characters. In MCF-7, Colo-205, and A549 xenograft models, compound 3c exhibited significant tumor growth inhibitions with low toxicities, which could be a promising drug candidate for further development.


Assuntos
Antineoplásicos/farmacologia , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Descoberta de Drogas , Inibidores de Proteínas Quinases/farmacologia , Células A549 , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Camundongos , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade
19.
Nat Neurosci ; 22(1): 91-105, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30559479

RESUMO

Early invasive growth along specific anatomical structures, especially the white matter tract, is regarded as one of the main causes of poor therapeutic outcome of people with gliomas. We show that some glioma stem cells (GSCs) are preferentially located along white matter tracts, which exhibit a demyelinated phenotype, at the invasive frontier of glioma tissues. These GSCs are CD133+Notch1+, whereas the nerve fibers express the Notch ligand Jagged1. The Notch-induced transcription factor Sox9 promotes the transcription of SOX2 and the methylation level of the NOTCH1 promoter is attenuated by the upregulation of SOX2 to reinforce NOTCH1 expression in GSCs. This positive-feedback loop in a cohort of glioma subjects is correlated with a poor prognosis. Inhibition of Notch signaling attenuates the white-matter-tract tropism of GSCs. These findings provide evidence indicating that the NOTCH1-SOX2 positive-feedback loop controls GSC invasion along white matter tracts.


Assuntos
Neoplasias Encefálicas/metabolismo , Retroalimentação Fisiológica/fisiologia , Glioma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Receptor Notch1/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Substância Branca/metabolismo , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Imagem de Tensor de Difusão , Glioma/diagnóstico por imagem , Glioma/patologia , Humanos , Proteína Jagged-1/metabolismo , Invasividade Neoplásica/patologia , Células-Tronco Neoplásicas/patologia , Substância Branca/patologia
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