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1.
Front Public Health ; 12: 1408316, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39319291

RESUMO

Objectives: To provide valuable insights for targeted interventions and resource allocation, our analysis delved into the multifaceted burden, trends, risks, and projections of multi drug resistant tuberculosis (MDR-TB). Methods: This research employed data from the Global Burden of Disease (GBD) 2019 dataset, which used a comparative risk assessment to quantify the disease burden resulting from risk factors. Initially, this database was utilized to extract details concerning the disability-adjusted life years (DALYs), mortality, incidence, and the number of individuals afflicted by MDR-TB. Subsequently, regression analyses were conducted using the Joinpoint program to figure average annual percent change (AAPC) to ascertain the trend. Thirdly, the age-period-cohort model (APCM) was adopted to analyze evolutions in incidence and mortality. Finally, utilizing the Nordpred model within R software, we projected the incidence and mortality of MDR-TB from 2020 to 2030. Results: MDR-TB remained a pressing global health concern in regions with lower socio-demographic indexes (SDI), where the AAPC in DALYs topped 7% from 1990 to 2019. In 2019, the cumulative DALYs attributed to MDR-TB tallied up to 4.2 million, with India, the Russian Federation, and China bearing the brunt. Notably, the incidence rates have shown a steadfast presence over the past decade, and a troubling forecast predicts an uptick in these areas from 2020 to 2030. Additionally, the risk of contracting MDR-TB grew with advancing age, manifesting most acutely among men aged 40+ in lower SDI regions. Strikingly, alcohol consumption had been identified as a significant contributor, surpassing the impacts of smoking and high fasting plasma glucose, leading to 0.7 million DALYs in 2019. Conclusions: A robust strategy is needed to end tuberculosis (TB) by 2030, especially in lower SDI areas.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Masculino , Incidência , Feminino , Adulto , Pessoa de Meia-Idade , Carga Global da Doença , Saúde Global/estatística & dados numéricos , Anos de Vida Ajustados por Deficiência , Fatores de Risco , Adolescente , Idoso , Adulto Jovem , Medição de Risco
2.
J Med Chem ; 66(24): 16783-16806, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-38085679

RESUMO

The chromatin-associated protein WDR5 (WD repeat domain 5) is an essential cofactor for MYC and a conserved regulator of ribosome protein gene transcription. It is also a high-profile target for anti-cancer drug discovery, with proposed utility against both solid and hematological malignancies. We have previously discovered potent dihydroisoquinolinone-based WDR5 WIN-site inhibitors with demonstrated efficacy and safety in animal models. In this study, we sought to optimize the bicyclic core to discover a novel series of WDR5 WIN-site inhibitors with improved potency and physicochemical properties. We identified the 3,4-dihydrobenzo[f][1,4]oxazepin-5(2H)-one core as an alternative scaffold for potent WDR5 inhibitors. Additionally, we used X-ray structural analysis to design partially saturated bicyclic P7 units. These benzoxazepinone-based inhibitors exhibited increased cellular potency and selectivity and favorable physicochemical properties compared to our best-in-class dihydroisoquinolinone-based counterparts. This study opens avenues to discover more advanced WDR5 WIN-site inhibitors and supports their development as novel anti-cancer therapeutics.


Assuntos
Antineoplásicos , Repetições WD40 , Animais , Descoberta de Drogas , Antineoplásicos/farmacologia
3.
Proc Natl Acad Sci U S A ; 120(1): e2211297120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36574664

RESUMO

WD repeat domain 5 (WDR5) is a core scaffolding component of many multiprotein complexes that perform a variety of critical chromatin-centric processes in the nucleus. WDR5 is a component of the mixed lineage leukemia MLL/SET complex and localizes MYC to chromatin at tumor-critical target genes. As a part of these complexes, WDR5 plays a role in sustaining oncogenesis in a variety of human cancers that are often associated with poor prognoses. Thus, WDR5 has been recognized as an attractive therapeutic target for treating both solid and hematological tumors. Previously, small-molecule inhibitors of the WDR5-interaction (WIN) site and WDR5 degraders have demonstrated robust in vitro cellular efficacy in cancer cell lines and established the therapeutic potential of WDR5. However, these agents have not demonstrated significant in vivo efficacy at pharmacologically relevant doses by oral administration in animal disease models. We have discovered WDR5 WIN-site inhibitors that feature bicyclic heteroaryl P7 units through structure-based design and address the limitations of our previous series of small-molecule inhibitors. Importantly, our lead compounds exhibit enhanced on-target potency, excellent oral pharmacokinetic (PK) profiles, and potent dose-dependent in vivo efficacy in a mouse MV4:11 subcutaneous xenograft model by oral dosing. Furthermore, these in vivo probes show excellent tolerability under a repeated high-dose regimen in rodents to demonstrate the safety of the WDR5 WIN-site inhibition mechanism. Collectively, our results provide strong support for WDR5 WIN-site inhibitors to be utilized as potential anticancer therapeutics.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias , Repetições WD40 , Animais , Humanos , Camundongos , Cromatina , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Modelos Animais , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
4.
J Med Chem ; 65(8): 6287-6312, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35436124

RESUMO

WD repeat domain 5 (WDR5) is a nuclear scaffolding protein that forms many biologically important multiprotein complexes. The WIN site of WDR5 represents a promising pharmacological target in a variety of human cancers. Here, we describe the optimization of our initial WDR5 WIN-site inhibitor using a structure-guided pharmacophore-based convergent strategy to improve its druglike properties and pharmacokinetic profile. The core of the previous lead remained constant while a focused SAR effort on the three pharmacophore units was combined to generate a new in vivo lead series. Importantly, this new series of compounds has picomolar binding affinity, improved cellular antiproliferative activity and selectivity, and increased kinetic aqueous solubility. They also exhibit a desirable oral pharmacokinetic profile with manageable intravenous clearance and high oral bioavailability. Thus, these new leads are useful probes toward studying the effects of WDR5 inhibition.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Humanos , Repetições WD40
5.
J Med Chem ; 63(2): 656-675, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31858797

RESUMO

WD repeat domain 5 (WDR5) is a member of the WD40-repeat protein family that plays a critical role in multiple chromatin-centric processes. Overexpression of WDR5 correlates with a poor clinical outcome in many human cancers, and WDR5 itself has emerged as an attractive target for therapy. Most drug-discovery efforts center on the WIN site of WDR5 that is responsible for the recruitment of WDR5 to chromatin. Here, we describe discovery of a novel WDR5 WIN site antagonists containing a dihydroisoquinolinone bicyclic core using a structure-based design. These compounds exhibit picomolar binding affinity and selective concentration-dependent antiproliferative activities in sensitive MLL-fusion cell lines. Furthermore, these WDR5 WIN site binders inhibit proliferation in MYC-driven cancer cells and reduce MYC recruitment to chromatin at MYC/WDR5 co-bound genes. Thus, these molecules are useful probes to study the implication of WDR5 inhibition in cancers and serve as a potential starting point toward the discovery of anti-WDR5 therapeutics.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Quinolonas/síntese química , Quinolonas/farmacologia , Repetições WD40/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Cromatina/efeitos dos fármacos , Cromatina/genética , Cristalografia por Raios X , Desenho de Fármacos , Descoberta de Drogas , Repressão Epigenética/efeitos dos fármacos , Genes myc/efeitos dos fármacos , Humanos , Relação Estrutura-Atividade
6.
Cell Mol Biol Lett ; 23: 43, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30202418

RESUMO

BACKGROUND: Lnc-DC is a specific group of long non-coding (Lnc) RNAs in dendritic cells (DCs). Its function has been previously studied, and includes roles in dendritic cell differentiation and the progression of some diseases. In this study, we observed the critical role of Lnc-DC in regulating the differentiation, growth, and apoptosis of dendritic cells. METHODS: We first isolated peripheral blood mononuclear cells to culture and induce into DCs, which were then co-cultured with hepatitis B virus (HBV)-secreting HepG2.2.15 cells for the detection of changes in Lnc-DC. The expression levels of TLR9, p-STAT3, and SOCS3 were tested with qPCR and western blot. MTT assays were used to analyze the cell proliferation, cell cycle, and apoptosis. We used ELISA to test the expression of TNF-α, IL-1ß, IL-6, IL-12p40, and IFN-γ. RESULTS: Co-culture with HBV-secreting HepG2.2.15 cells increased the level of Lnc-DC and activated TLR9/STAT3 signaling. The HBV DNA level (IU/ml) was positively correlated with levels of Lnc-DC and TLR9, further demonstrating that Lnc-DC was associated with the immune response of HBV. Lnc-DC was shown to regulate TLR9/STAT3 signaling in dendritic cells. More interestingly, the regulation of Lnc-DC controlled the immune response by reducing the concentration of secreted TNF-α, IL-6, IL-12, and IFN-γ, as well as increasing the IL-1ß concentration in dendritic cells. CONCLUSION: Lnc-DC is important in regulating the growth, apoptosis, and immune response of dendritic cells mediated by TLR9/STAT3 signaling, and was also activated by HBV. This study provides a previously unidentified mechanism underlying the immune response in dendritic cells.


Assuntos
Células Dendríticas/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , RNA Longo não Codificante/imunologia , Fator de Transcrição STAT3/imunologia , Transdução de Sinais , Receptor Toll-Like 9/imunologia , Apoptose , Proliferação de Células , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/virologia , Células Hep G2 , Humanos
7.
Oncol Lett ; 15(5): 6519-6526, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29725402

RESUMO

The objective of the present study was to investigate the association of B7-H3 expression and cluster of differentiation (CD)163+ tumor-associated macrophage (TAM) infiltration with clinicopathological parameters in urothelial cell carcinoma of the bladder (UCB), and to investigate their potential conjoint effects on progression of UCB. B7-H3 expression and CD163+ TAM infiltration in tumor specimens from 134 consecutive patients that underwent radical cystectomy for UCB were tested using immunohistochemistry, followed by statistical analysis. In these 134 patients, B7-H3 expression and CD163+ TAM infiltration in the bladder carcinoma tissues were significantly associated with an increased ratio of vascular invasion (P=0.009; P=0.012) and distant metastasis (P=0.015; P=0.038); however, they were not associated with gender, age, pathologic grade, tumor stage, recurrence or lymphatic metastasis. The results of χ2 test analysis indicated that CD163+ TAM infiltration and B7-H3 expression were positively correlated (χ2=20.714; P<0.001). Overall survival (OS) and progression-free survival (PFS) rates were significantly worsened by high B7-H3 expression (P=0.002; P=0.020). However, CD163+ TAM infiltration was not associated with OS or PFS rate. Notably, the OS and PFS rates in patients with high B7-H3 expression or high CD163+ TAM infiltration were significantly poorer than the patients with low B7-H3 expression (P<0.001; P<0.001) or low CD163+ TAM infiltration (P=0.022; P=0.017) in the subgroup of 115 patients with muscle-invasive bladder cancer. The results of the present study indicate that B7-H3 expression level could be used as an independent prognostic indicator following radical cystectomy for UCB and patients with high B7-H3 expression and high CD163+ TAM infiltration experience a poorer prognosis.

8.
Front Plant Sci ; 8: 2205, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312429

RESUMO

As an allotetraploid oilcrop, Brassica napus contains four duplicated Acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) genes, which catalyze one of the rate-limiting steps in triacylglycerol (TAG) biosynthesis in plants. While all four BnDGAT1s have been expressed functionally in yeast, their expression patterns in different germplasms and tissues and also consequent contribution to seed oil accumulation in planta remain to be elucidated. In this study, the coding regions of the four BnDGAT1s were expressed in an Arabidopsis dgat1 mutant. All four BnDGAT1s showed similar effects on oil content and fatty acid composition, a result which is different from that observed in previous studies of their expression in yeast. Expression patterns of BnDGAT1s were analyzed in developing seeds of 34 B. napus inbred lines and in different tissues of 14 lines. Different expression patterns were observed for the four BnDGAT1s, which suggests that they express independently or randomly in different germplasm sources. Higher expression of BnDGAT1s was correlated with higher seed oil content lines. Tissue-specific analyses showed that the BnDGAT1s were expressed in a uniform pattern in different tissues. Our results suggest that it is important to maintain expression of the four BnDGAT1s for maximum return on oil content.

9.
J Mater Chem B ; 3(23): 4698-4706, 2015 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32262485

RESUMO

The charge-reversal strategy is usually employed in gene delivery to facilitate the endosomal escape of gene carriers and the release of the payload into cytoplasm. However, most of the charge-reversal materials are far from perfect biocompatible materials due to the cytotoxicity of themselves or their hydrolyzed products. In this study, an excellent charge-reversal material named modified bovine serum albumin (mBSA) was prepared. The charge reversal of biocompatible mBSA is a physical process and can instantly occur, which was confirmed by zeta potential, size detection and morphological studies. The introduction of mBSA can not only reduce the zeta potential of binary complexes (pDNA-PEI) but also increase the nuclease resistance ability of the pDNA-PEI binary complexes. In addition, cell viabilities tested by MTT assay and gene transfection assay demonstrated that mBSA can reduce the cytotoxicity of pDNA-PEI polyplexes and improve their gene transfection efficiency (serum free and 10% FBS medium) both in 293T and HepG2 cells at the same time. The experimental results of cell internalization and intracellular distribution of pDNA-PEI-mBSA ternary complexes confirmed that the improvement of transfection efficiency originated from the enhancement of endosomal escape of polyplexes. Therefore, mBSA has been proven to be a perfect charge-reversal platform to simultaneously improve the transfection efficiency and biocompatibility of polyplexes.

10.
PLoS One ; 8(12): e80569, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24312482

RESUMO

Increasing seed oil content is one of the most important goals in breeding of rapeseed (B. napus L.). To dissect the genetic basis of oil content in B. napus, a large and new double haploid (DH) population containing 348 lines was obtained from a cross between 'KenC-8' and 'N53-2', two varieties with >10% difference in seed oil content, and this population was named the KN DH population. A genetic linkage map consisting of 403 markers was constructed, which covered a total length of 1783.9 cM with an average marker interval of 4.4 cM. The KN DH population was phenotyped in eight natural environments and subjected to quantitative trait loci (QTL) analysis for oil content. A total of 63 identified QTLs explaining 2.64-17.88% of the phenotypic variation were identified, and these QTLs were further integrated into 24 consensus QTLs located on 11 chromosomes using meta-analysis. A high-density consensus map with 1335 marker loci was constructed by combining the KN DH map with seven other published maps based on the common markers. Of the 24 consensus QTLs in the KN DH population, 14 were new QTLs including five new QTLs in A genome and nine in C genome. The analysis revealed that a larger population with significant differences in oil content gave a higher power detecting new QTLs for oil content, and the construction of the consensus map provided a new clue for comparing the QTLs detected in different populations. These findings enriched our knowledge of QTLs for oil content and should be a potential in marker-assisted breeding of B. napus.


Assuntos
Brassica napus/genética , Cruzamentos Genéticos , Ligação Genética , Genoma de Planta/fisiologia , Óleos de Plantas , Locos de Características Quantitativas/fisiologia , Sementes/genética , Brassica napus/metabolismo , Mapeamento Cromossômico/métodos , Sementes/metabolismo
11.
J Proteome Res ; 12(11): 4965-78, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24053668

RESUMO

Ultrastructural observations, combined with proteomic and comparative genomic analyses, were applied to interpret the differences in protein composition and oil-body characteristics of mature seed of two Brassica napus lines with high and low oil contents of 55.19% and 36.49%, respectively. The results showed that oil bodies were arranged much closer in the high than in the low oil content line, and differences in cell size and thickness of cell walls were also observed. There were 119 and 32 differentially expressed proteins (DEPs) of total and oil-body proteins identified. The 119 DEPs of total protein were mainly involved in the oil-related, dehydration-related, storage and defense/disease, and some of these may be related to oil formation. The DEPs involved with dehydration-related were both detected in total and oil-body proteins for high and low oil lines and may be correlated with the number and size of oil bodies in the different lines. Some genes that corresponded to DEPs were confirmed by quantitative trait loci (QTL) mapping analysis for oil content. The results revealed that some candidate genes deduced from DEPs were located in the confidence intervals of QTL for oil content. Finally, the function of one gene that coded storage protein was verified by using a collection of Arabidopsis lines that can conditionally express the full length cDNA from developing seeds of B. napus.


Assuntos
Brassica napus/química , Brassica napus/genética , Óleos de Plantas/análise , Proteínas de Plantas/metabolismo , Sementes/química , Arabidopsis , Brassica napus/metabolismo , Tamanho Celular , DNA Complementar/genética , Eletroforese em Gel Bidimensional , Ácidos Graxos/análise , Genômica/métodos , Glucosinolatos/análise , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Proteômica/métodos , Locos de Características Quantitativas/genética , Especificidade da Espécie
12.
J Am Chem Soc ; 132(32): 11058-70, 2010 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-20698672

RESUMO

NMR spectroscopy and molecular dynamics (MD) simulations were used to probe the structure and dynamics of complexes of three phosphotyrosine-derived peptides with the Src SH2 domain in an effort to uncover a structural explanation for enthalpy-entropy compensation observed in the binding thermodynamics. The series of phosphotyrosine peptide derivatives comprises the natural pYEEI Src SH2 ligand, a constrained mimic, in which the phosphotyrosine (pY) residue is preorganized in the bound conformation for the purpose of gaining an entropic advantage to binding, and a flexible analogue of the constrained mimic. The expected gain in binding entropy of the constrained mimic was realized; however, a balancing loss in binding enthalpy was also observed that could not be rationalized from the crystallographic structures. We examined protein dynamics to evaluate whether the observed enthalpic penalty might be the result of effects arising from altered motions in the complex. (15)N-relaxation studies and positional fluctuations from molecular dynamics indicate that the main-chain dynamics of the protein show little variation among the three complexes. Root mean squared (rms) coordinate deviations vary by less than 1.5 A for all non-hydrogen atoms for the crystal structures and in the ensemble average structures calculated from the simulations. In contrast to this striking similarity in the structures and dynamics, there are a number of large chemical shift differences from residues across the binding interface, but particularly from key Src SH2 residues that interact with pY, the "hot spot" residue, which contributes about one-half of the binding free energy. Rank-order correlations between chemical shifts and ligand binding enthalpy for several pY-binding residues, coupled with available mutagenesis and calorimetric data, suggest that subtle structural perturbations (<1 A) from the conformational constraint of the pY residue sufficiently alter the geometry of enthalpically critical interactions in the binding pocket to cause the loss of binding enthalpy, leading to the observed enthalpy-entropy compensation. We find no evidence to support the premise that enthalpy-entropy compensation is an inherent property and conclude that preorganization of Src SH2 ligand residues involved in binding hot spots may eventuate in suboptimal interactions with the domain. We propose that introducing constraints elsewhere in the ligand could minimize enthalpy-entropy compensation effects. The results illustrate the utility of the NMR chemical shift to highlight small, but energetically significant, perturbations in structure that might otherwise go unnoticed in an apparently rigid protein.


Assuntos
Entropia , Simulação de Dinâmica Molecular , Ressonância Magnética Nuclear Biomolecular , Domínios de Homologia de src , Ligantes , Proteína Oncogênica pp60(v-src)/química , Proteína Oncogênica pp60(v-src)/metabolismo , Ligação Proteica
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