Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Mol Divers ; 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38183513

RESUMO

Thymidylate kinase (TMPK) of monkeypox virus (MPXV) has emerged as a promising target for potential therapeutics due to its significant role in pyrimidine metabolism. While smallpox drugs are advised for treating monkeypox, the European Medicine Agency has sanctioned Tecovirimat due to its potent nanomolar activity. Nonetheless, there is a need for monkeypox-specific therapeutic options. In this work, we employed docking-based virtual screening and molecular dynamics (MD) simulations to identify myxobacterial secondary metabolites as promising anti-viral natural compounds capable of inhibiting thymidylate kinase. The computational pharmacokinetics and manual curation of top-scoring compounds identified six lead compounds that were compared in terms of protein-ligand contacts and protein-essential dynamics. The study shows that among the six candidates, Aurachin A and the Soraphinol analogues such as Soraphinol A and Soraphinol C remain very stable compared to other compounds, enabling the active site integrity via a stable dynamics pattern. We also show that other compounds such as Phenoxan, Phenylnannolone C, and 8E-Aurafuron B remain unstable and have a negative impact on the active site integrity and may not be suitable binders for TMPK protein. Analyzing the Aurachin A and Soraphinol A binding, the established hydrogen bonds with Arg93 and the conserved hydrophobic interaction with Tyr101 are consistent with previous experimental interactions. Additionally, a deeper insight into the indole and the aromatic ring interaction through π-π stacking and π-cation interactions, as well as the background of Aurachin A and Soraphinol A as a bioactive compound, has significant implications not only for its potential as a promising drug but also for directing future drug discovery efforts targeting the TMPK protein.

2.
Chin J Cancer Res ; 36(2): 195-214, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38751441

RESUMO

Hepatocellular carcinoma (HCC) is considered the fifth most prevalent cancer among all types of cancers and has the third most morbidity value. It has the most frequent duplication time and a high recurrence rate. Recently, the most unique technique used is liquid biopsies, which carry many markers; the most prominent is circulating tumor DNA (ctDNA). Varied methods are used to investigate ctDNA, including various forms of polymerase chain reaction (PCR) [emulsion PCR (ePCR), digital PCR (dPCR), and bead, emulsion, amplification, magnetic (BEAMing) PCR]. Hence ctDNA is being recognized as a potential biomarker that permits early cancer detection, treatment monitoring, and predictive data on tumor burden are subjective to therapy or surgery. Numerous ctDNA biomarkers have been investigated based on their alterations such as 1) single nucleotide variations (either insertion or deletion of a nucleotide) markers including TP53, KRAS, and CCND1; 2) copy number variations which include markers such as CDK6, EFGR, MYC and BRAF; 3) DNA methylation (RASSF1A, SEPT9, KMT2C and CCNA2); 4) homozygous mutation includes ctDNA markers as CDKN2A, AXIN1; and 5) gain or loss of function of the genes, particularly for HCC. Various researchers have conducted many studies and gotten fruitful results. Still, there are some drawbacks to ctDNA namely low quantity, fragment heterogeneity, less stability, limited mutant copies and standards, and differential sensitivity. However, plenty of investigations demonstrate ctDNA's significance as a polyvalent biomarker for cancer and can be viewed as a future diagnostic, prognostic and therapeutic agent. This article overviews many conditions in genetic changes linked to the onset and development of HCC, such as dysregulated signaling pathways, somatic mutations, single-nucleotide polymorphisms, and genomic instability. Additionally, efforts are also made to develop treatments for HCC that are molecularly targeted and to unravel some of the genetic pathways that facilitate its early identification.

3.
Br J Cancer ; 129(9): 1397-1408, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37543671

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs)-related immune genes (lrRIGs) play a crucial role in the development and progression of lung adenocarcinoma (LUAD). However, reliable prognostic signatures based on lrRIGs have not yet been identified. METHODS: We screened lrRIGs associated with the prognosis of LUAD using The Cancer Genome Atlas (TCGA) database and then established a novel prognostic nine-gene signature composed of CD79A, INHA, SHC3, LIFR, TNFRSF11A, GPI, F2RL1, SEMA7A and WFDC2 through bioinformatic approaches. A risk score derived from this gene signature was used to divide LUAD patients into the low- and high-risk groups. The latter was confirmed to have markedly worse overall survival (O.S.). A nomogram was developed using the risk score and other independent prognostic elements, demonstrating excellent performance in predicting the O.S. rate of LUAD patients. RESULTS: We observed that the infiltration of diverse immune cell subtypes and response to immunotherapy and chemotherapy significantly differed between the low- and high-risk groups. CONCLUSIONS: Overall, stratification based on this gene signature could be used to guide better therapeutic management and improve outcomes for LUAD patients.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , Imunoterapia , Biologia Computacional , Pulmão , Prognóstico
4.
J Gastroenterol Hepatol ; 38(1): 138-152, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36300571

RESUMO

BACKGROUND AND AIM: Liver cancer stem cells (LCSCs) cause therapeutic refractoriness and relapse in hepatocellular carcinoma. Heat shock factor 1 (HSF1) plays versatile roles in multiple cancers. However, the role of HSF1 in LCSCs is not well understood. This study investigated the function and signal mechanisms of HSF1 in maintaining LCSC phenotypes. METHODS: We established two LCSC lines, HepG2-R and HuH-7-R. Constitutive activation of HSF1 was observed in these LCSCs. Specific short hairpin RNAs (shRNAs) and chemical inhibitors were used to identify the relationship between HSF1 expression and LCSCs phenotypes. RESULTS: We revealed a concomitant activation modality involving HSF1 and STAT3 in LCSCs and liver cancer tissues. We also found that liver cancer patients whose HSF1 and STAT3 mRNA expression levels were high presented with unfavorable clinicopathological characteristics. Moreover, the secretion of interleukin-8 (IL-8) was elevated in the LCSC medium and was directly regulated by HSF1 at the transcriptional level. In turn, IL-8 activated HSF1 and STAT3 signaling, and a neutralizing IL-8 antibody inhibited HSF1 and STAT3 activity, reduced cancer stem cell marker expression, and decreased LCSC microsphere formation. Simultaneous intervention with HSF1 and STAT3 led to synergistically suppressed stemness acquisition and growth suppression in the LCSCs in vivo and in vitro. CONCLUSIONS: Our study indicates that IL-8 mediates the crosstalk between the HSF1 and Stat3 signaling pathways in LCSCs and that the combined targeting of HSF1 and STAT3 is a promising treatment strategy for patients with advanced liver cancer.


Assuntos
Fatores de Transcrição de Choque Térmico , Neoplasias Hepáticas , Células-Tronco Neoplásicas , Fator de Transcrição STAT3 , Humanos , Comunicação Autócrina , Linhagem Celular Tumoral , Fatores de Transcrição de Choque Térmico/metabolismo , Interleucina-8/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
5.
Appl Opt ; 62(17): 4543-4550, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707150

RESUMO

It is important to determine the ideal combination of housing materials, groups of refractive materials, and their optical powers for athermalizing achromatic and apochromatic optical systems. This study proposes a combined design approach that utilizes three or more glass types to resolve thermal aberrations and defocus achromatic and apochromatic optical systems. It selects a suitable glass type using a 3D glass chart and calculates the optical power analytically. Furthermore, a temperature-insensitive optical system with a 450-750 nm band based on refractive materials (CDGM Glass Co., Ltd.) is designed, with the modular transfer function value of the center field of view decreasing by less than 0.024 in the temperature range of -40∘ C to +80∘ C and the secondary spectrum aberration decreasing by over three times and being maintained within 0.08 mm.

6.
Int J Med Sci ; 17(12): 1803-1810, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714083

RESUMO

Since the end of 2019, a new type of coronavirus pneumonia (COVID-19) caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has been spreading rapidly throughout the world. Previously, there were two outbreaks of severe coronavirus caused by different coronaviruses worldwide, namely Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). This article introduced the origin, virological characteristics and epidemiological overview of SARS-CoV-2, reviewed the currently known drugs that may prevent and treat coronavirus, explained the characteristics of the new coronavirus and provided novel information for the prevention and treatment of COVID-19.


Assuntos
Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/prevenção & controle , Amidas/farmacologia , Amidas/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Betacoronavirus/isolamento & purificação , Betacoronavirus/fisiologia , COVID-19 , Cloroquina/análogos & derivados , Cloroquina/uso terapêutico , Clorpromazina/uso terapêutico , Coronavirus/genética , Infecções por Coronavirus/genética , Ciclofilinas/antagonistas & inibidores , Desenvolvimento de Medicamentos , Reposicionamento de Medicamentos , Medicamentos de Ervas Chinesas/uso terapêutico , Endocitose/efeitos dos fármacos , Humanos , Soros Imunes , Indutores de Interferon/uso terapêutico , Inibidores da Síntese de Ácido Nucleico/farmacologia , Inibidores da Síntese de Ácido Nucleico/uso terapêutico , Pneumonia Viral/genética , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Resveratrol/farmacologia , Resveratrol/uso terapêutico , SARS-CoV-2 , Vacinas Virais/uso terapêutico , Tratamento Farmacológico da COVID-19
7.
J Cell Mol Med ; 23(3): 1698-1713, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30637920

RESUMO

Tumour necrosis factor-α-induced protein 8-like 2 (TIPE2) is a tumour suppressor in many types of cancer. However, the mechanism of action of TIPE2 on the growth of rectal adenocarcinoma is unknown. Our results showed that the expression levels of TIPE2 in human rectal adenocarcinoma tissues were higher than those in adjacent non-tumour tissues. Overexpression of TIPE2 reduced the proliferation, migration, and invasion of human rectal adenocarcinoma cells and down-regulation of TIPE2 showed reverse effects. TIPE2 overexpression increased apoptosis through down-regulating the expression levels of Wnt3a, phospho (p)-ß-Catenin, and p-glycogen synthase kinase-3ß in rectal adenocarcinoma cells, however, TIPE2 knockdown exhibited reverse trends. TIPE2 overexpression decreased autophagy by reducing the expression levels of p-Smad2, p-Smad3, and transforming growth factor-beta (TGF-ß) in rectal adenocarcinoma cells, however, TIPE2 knockdown showed opposite effects. Furthermore, TIPE2 overexpression reduced the growth of xenografted human rectal adenocarcinoma, whereas TIPE2 knockdown promoted the growth of rectal adenocarcinoma tumours by modulating angiogenesis. In conclusion, TIPE2 could regulate the proliferation, migration, and invasion of human rectal adenocarcinoma cells through Wnt/ß-Catenin and TGF-ß/Smad2/3 signalling pathways. TIPE2 is a potential therapeutic target for the treatment of rectal adenocarcinoma.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Retais/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Animais , Apoptose , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Neoplasias Retais/genética , Neoplasias Retais/metabolismo , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína Smad3/genética , Proteína Smad3/metabolismo , Taxa de Sobrevida , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Arch Virol ; 164(8): 2023-2029, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31111259

RESUMO

We previously obtained mouse-adapted variants of H1N2 avian influenza virus that contained PB2-L134H, PB2-I647L, PB2-D701N, HA-G228S, and M1-D231N mutations. Here, we analyzed the effects of these mutations on viral pathogenicity in a mammalian model. By evaluating the virulence of mouse-adapted H1N2 variants at different generations, we found that the PB2-D701N and HA-G228S mutations both contribute to the virulence of this virus in mammals. Furthermore, we found that the PB2-D701N and HA-G228S mutations both enhance the ability of the virus to replicate in vivo and in vitro and that the PB2-D701N substitution results in an expansion of viral tissue tropism. These results suggest that the PB2-D701N mutation and the HA-G228S mutation are the major mammalian determinants of H1N2 virus. These results help us to understand more about the mechanisms by which influenza viruses adapt to mammals, and monitoring of these mutations can be used in continuous influenza surveillance to assess the pandemic potential of avian influenza virus variants.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N2/genética , Influenza Aviária/virologia , Mutação/genética , Proteínas Virais/genética , Virulência/genética , Adaptação Biológica/genética , Substituição de Aminoácidos/genética , Animais , Aves , Linhagem Celular , Cães , Feminino , Células Madin Darby de Rim Canino , Mamíferos/virologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/virologia , Fenótipo , Replicação Viral/genética
9.
J Cell Mol Med ; 20(6): 1095-105, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26864945

RESUMO

The development of multidrug resistance (MDR) not only actively transports a wide range of cytotoxic drugs across drug transporters but is also a complex interaction between a number of important cellular signalling pathways. Nitric oxide donors appear to be a new class of anticancer therapeutics for satisfying all the above conditions. Previously, we reported furoxan-based nitric oxide-releasing compounds that exhibited selective antitumour activity in vitro and in vivo. Herein, we demonstrate that bifendate (DDB)-nitric oxide, a synthetic furoxan-based nitric oxide-releasing derivative of bifendate, effectively inhibits the both sensitive and MDR tumour cell viability at a comparatively low concentration. Interestingly, the potency of DDB-nitric oxide is the independent of inhibition of the functions and expressions of three major ABC transporters. The mechanism of DDB-nitric oxide appears to be in two modes of actions by inducing mitochondrial tyrosine nitration and apoptosis, as well as by down-regulating HIF-1α expression and protein kinase B (AKT), extracellular signal-regulated kinases (ERK), nuclear factor κB (NF-κB) activation in MDR cells. Moreover, the addition of a typical nitric oxide scavenger significantly attenuated all the effects of DDB-nitric oxide, indicating that the cytotoxicity of DDB-nitric oxide is as a result of higher levels of nitric oxide release in MDR cancer cells. Given that acquired MDR to nitric oxide donors is reportedly difficult to achieve and genetically unstable, compound like DDB-nitric oxide may be a new type of therapeutic agent for the treatment of MDR tumours.


Assuntos
Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Óxido Nítrico/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/química , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HEK293 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células K562 , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo
10.
Arch Virol ; 161(4): 867-72, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26733295

RESUMO

We conducted a serological survey to detect antibodies against avian influenza virus (AIV) in Gazella subgutturosa, Canis lupus, Capreolus pygargus, Sus scrofa, Cervus elaphus, Capra ibex, Ovis ammon, Bos grunniens and Pseudois nayaur in Xinjiang, China. Two hundred forty-six sera collected from 2009 to 2013 were assayed for antibodies against H5, H7 and H9 AIVs using hemagglutination inhibition (HI) tests and a pan-influenza competitive ELISA. Across all tested wildlife species, 4.47 % harbored anti-AIV antibodies that were detected by the HI assay. The seroprevalence for each AIV subtype across all species evaluated was 0 % for H5 AIV, 0.81 % for H7 AIV, and 3.66 % for H9 AIV. H7-reactive antibodies were found in Canis lupus (9.09 %) and Ovis ammon (4.55 %). H9-reactive antibodies were found in Gazella subgutturosa (4.55 %), Canis lupus (27.27 %), Pseudois nayaur (23.08 %), and Ovis ammon (4.55 %). The pan-influenza competitive ELISA results closely corresponded to the cumulative prevalence of AIV exposure as measured by subtype-specific HI assays, suggesting that H7 and H9 AIV subtypes predominate in the wildlife species evaluated. These data provide evidence of prior infection with H7 and H9 AIVs in non-avian wildlife in Xinjiang, China.


Assuntos
Animais Selvagens , Vírus da Influenza A/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Animais , China/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Vírus da Influenza A/classificação , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Estudos Soroepidemiológicos
11.
Arch Virol ; 160(5): 1267-77, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25782865

RESUMO

The worldwide circulation of H9N2 avian influenza virus in poultry, the greater than 2.3 % positive rate for anti-H9 antibodies in poultry-exposed workers, and several reports of human infection indicate that H9N2 virus is a potential threat to human health. Here, we found three mutations that conferred high virulence to H9N2 virus in mice after four passages. The PB2-E627K substitution rapidly appeared at the second passage and played a decisive role in virulence. Polymerase complexes possessing PB2-E627K displayed 16.1-fold higher viral polymerase activity when compared to the wild-type virus, which may account for enhanced virulence of this virus. The other two substitutions (HA-N313D and HA-N496S) enhanced binding to both α2,3-linked and α2,6-linked sialic acid receptors; however, the HA-N313D and N496S substitutions alone decreased the virulence of mouse-adapted virus. Furthermore, this mouse-adapted virus was still not transmissible among guinea pigs by direct contact (0/3 pairs). Our findings show that adaption in mice enhanced the viral polymerase activity and receptor-binding ability, which resulted in a virulent phenotype in mice but not a transmissible phenotype in guinea pigs, indicating that host factors play an important role in adaptive evolution of influenza in new hosts.


Assuntos
Adaptação Biológica , Substituição de Aminoácidos , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Infecções por Orthomyxoviridae/virologia , RNA Polimerase Dependente de RNA/genética , Proteínas Virais/genética , Animais , Feminino , Cobaias , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/crescimento & desenvolvimento , Vírus da Influenza A Subtipo H9N2/fisiologia , Camundongos Endogâmicos BALB C , Mutação de Sentido Incorreto , Infecções por Orthomyxoviridae/transmissão , RNA Polimerase Dependente de RNA/metabolismo , Inoculações Seriadas , Proteínas Virais/metabolismo , Virulência , Ligação Viral , Replicação Viral
12.
Biochem Biophys Res Commun ; 455(3-4): 318-22, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25446092

RESUMO

We previously described bifendate-chalcone hybrids as potent P-glycoprotein inhibitors. In the present work, we determine whether these compounds could reverse breast cancer resistance protein (BCRP, ABCG2)-mediated multidrug resistance using HEK293/BCRP cells which was BCRP-transfected stable HEK293 cells. Results indicated that compounds 8d, 8f, 8g and 8h could significantly enhance mitoxantrone accumulation in HEK293/BCRP cells via inhibiting BCRP drug efflux function. The most active compound 8g exhibited little intrinsic cytotoxicity (IC50>100 µM), and could reverse BCRP-mediated drug resistance independent of decreasing BCRP expression level. Notably, 8g had little inhibitory effect on multidrug resistance-associated protein 1 (MRP1, ABCC1), another drug efflux transporter. The present findings, together with the previous results, suggest that 8g might be act as dual inhibitors of P-gp and BCRP.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Protocolos de Quimioterapia Combinada Antineoplásica/química , Compostos de Bifenilo/química , Chalcona/administração & dosagem , Chalcona/química , Proteínas de Neoplasias/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/química , Química Farmacêutica , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Humanos , Concentração Inibidora 50 , Proteínas de Neoplasias/química
13.
Life (Basel) ; 13(12)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38137909

RESUMO

Monkeypox (Mpox) is a virus that first emerged in Africa in 1970 [...].

14.
Life (Basel) ; 13(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36836879

RESUMO

Monkeypox virus is a double-stranded DNA virus species that causes disease in humans and mammals. It is a zoonotic virus belongs the genus Orthopoxviral, the family of Poxviridae, associated with the smallpox virus in many aspects. The first human case of monkeypox was reported throughout the Democratic Republic of Congo in 1970. In April 2022, several cases were recorded in widespread regions of Africa, the Northern and western hemispheres. The current review spotlights taxonomic classification, clinical presentations during infection, and the pathogenicity of the monkeypox virus in humans. Furthermore, the current review also highlights different diagnostics used for virus detection.

15.
Viruses ; 15(2)2023 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-36851785

RESUMO

Monkeypox is a serious public health issue in tropical and subtropical areas. Antivirals that target monkeypox proteins might lead to more effective and efficient therapy. The F13 protein is essential for the growth and maturation of the monkeypox virus. F13 inhibition might be a viable therapeutic target for monkeypox. The in silico fragment-based drug discovery method for developing antivirals may provide novel therapeutic options. In this study, we generated 800 compounds based on tecovirimat, an FDA-approved drug that is efficacious at nanomolar quantities against monkeypox. These compounds were evaluated to identify the most promising fragments based on binding affinity and pharmacological characteristics. The top hits from the chemical screening were docked into the active site of the F13 protein. Molecular dynamics simulations were performed on the top two probable new candidates from molecular docking. The ligand-enzyme interaction analysis revealed that the C2 ligand had lower binding free energy than the standard ligand tecovirimat. Water bridges, among other interactions, were shown to stabilize the C2 molecule. Conformational transitions and secondary structure changes in F13 protein upon C2 binding show more native three-dimensional folding of the protein. Prediction of pharmacological properties revealed that compound C2 may be promising as a drug candidate for monkeypox fever. However, additional in vitro and in vivo testing is required for validation.


Assuntos
Monkeypox virus , Mpox , Humanos , Ligantes , Simulação de Acoplamento Molecular , Antivirais/farmacologia , Benzamidas , Isoindóis
16.
Front Immunol ; 14: 1259612, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781384

RESUMO

Leishmania tropica is a vector-borne parasitic protozoa that is the leading cause of leishmaniasis throughout the global tropics and subtropics. L. tropica is a multidrug-resistant parasite with a diverse set of serological, biochemical, and genomic features. There are currently no particular vaccines available to combat leishmaniasis. The present study prioritized potential vaccine candidate proteins of L. tropica using subtractive proteomics and vaccinomics approaches. These vaccine candidate proteins were downstream analyzed to predict B- and T-cell epitopes based on high antigenicity, non-allergenic, and non-toxic characteristics. The top-ranked overlapping MHC-I, MHC-II, and linear B-cell epitopes were prioritized for model vaccine designing. The lead epitopes were linked together by suitable linker sequences to design multi-epitope constructs. Immunogenic adjuvant sequences were incorporated at the N-terminus of the model vaccine constructs to enhance their immunological potential. Among different combinations of constructs, four vaccine designs were selected based on their physicochemical and immunological features. The tertiary structure models of the designed vaccine constructs were predicted and verified. The molecular docking and molecular dynamic (MD) simulation analyses indicated that the vaccine design V1 demonstrated robust and stable molecular interactions with toll-like receptor 4 (TLR4). The top-ranked vaccine construct model-IV demonstrated significant expressive capability in the E. coli expression system during in-silico restriction cloning analysis. The results of the present study are intriguing; nevertheless, experimental bioassays are required to validate the efficacy of the predicted model chimeric vaccine.


Assuntos
Leishmania tropica , Vacinas , Simulação de Acoplamento Molecular , Leishmania tropica/genética , Proteômica , Escherichia coli , Epitopos de Linfócito T
17.
World J Gastroenterol ; 29(45): 5974-5987, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38130998

RESUMO

BACKGROUND: Trastuzumab constitutes the fundamental component of initial therapy for patients with advanced human epidermal growth factor receptor 2 (HER-2)-positive gastric cancer (GC). However, the efficacy of this treatment is hindered by substantial challenges associated with both primary and acquired drug resistance. While S-phase kinase associated protein 2 (Skp2) overexpression has been implicated in the malignant progression of GC, its role in regulating trastuzumab resistance in this context remains uncertain. Despite the numerous studies investigating Skp2 inhibitors among small molecule compounds and natural products, there has been a lack of successful commercialization of drugs specifically targeting Skp2. AIM: To discover a Skp2 blocker among currently available medications and develop a therapeutic strategy for HER2-positive GC patients who have experienced progression following trastuzumab-based treatment. METHODS: Skp2 exogenous overexpression plasmids and small interfering RNA vectors were utilized to investigate the correlation between Skp2 expression and trastuzumab resistance in GC cells. Q-PCR, western blot, and immunohistochemical analyses were conducted to evaluate the regulatory effect of thioridazine on Skp2 expression. A cell counting kit-8 assay, flow cytometry, a amplex red glucose/glucose oxidase assay kit, and a lactate assay kit were utilized to measure the proliferation, apoptosis, and glycolytic activity of GC cells in vitro. A xenograft model established with human GC in nude mice was used to assess thioridazine's effectiveness in vivo. RESULTS: The expression of Skp2 exhibited a negative correlation with the sensitivity of HER2-positive GC cells to trastuzumab. Thioridazine demonstrated the ability to directly bind to Skp2, resulting in a reduction in Skp2 expression at both the transcriptional and translational levels. Moreover, thioridazine effectively inhibited cell proliferation, exhibited antiapoptotic properties, and decreased the glucose uptake rate and lactate production by suppressing Skp2/protein kinase B/mammalian target of rapamycin/glucose transporter type 1 signaling pathways. The combination of thioridazine with either trastuzumab or lapatinib exhibited a more pronounced anticancer effect in vivo, surpassing the efficacy of either monotherapy. CONCLUSION: Thioridazine demonstrates promising outcomes in preclinical GC models and offers a novel therapeutic approach for addressing trastuzumab resistance, particularly when used in conjunction with lapatinib. This compound has potential benefits for patients with Skp2-proficient tumors.


Assuntos
Neoplasias Gástricas , Tioridazina , Humanos , Animais , Camundongos , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Lapatinib/farmacologia , Lapatinib/uso terapêutico , Tioridazina/farmacologia , Tioridazina/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Proteínas Quinases Associadas a Fase S/genética , Proteínas Quinases Associadas a Fase S/metabolismo , Camundongos Nus , Receptor ErbB-2/metabolismo , Proliferação de Células , Glicólise , Lactatos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Mamíferos
18.
Bioorg Med Chem Lett ; 22(8): 2675-80, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22450134

RESUMO

A series of substituted dibenzo[c,e]azepine-5-ones (7a-h) were synthesized and evaluated as P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) reversal agents. The most potent compound 7h could significantly and selectively enhance the chemo-sensitivity of drug-resistant K562/A02 cells to the cytotoxic effect of adriamycin (ADR) in a dose-dependent manner. Further studies indicated that 7h could markedly increase intracellular accumulation of both rhodamine 123 and ADR in K562/A02 cells and inhibit their efflux from the cells. And 7h had little effect on the levels of P-gp mRNA and protein in K562/A02 cells. These results suggest that the anti-MDR effect of 7h might be attributed to the inhibition of drug efflux function of P-gp, leading to the increased drug accumulation in K562/A02 cells, and thus the compound could be served as a lead for developing P-gp-mediated MDR reversal agents.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Azepinas/síntese química , Azepinas/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Antineoplásicos/química , Azepinas/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Células K562 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Bioorg Med Chem ; 20(8): 2540-8, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22429509

RESUMO

Overexpression of P-glycoprotein (P-gp) is one of the major problems to successful cancer chemotherapy. To find novel effective P-gp inhibitors, a series of bifendate-chalcone hybrids were synthesized and evaluated. Among them, the most active compound 8g had little intrinsic cytotoxicity (IC(50)>200 µM), and could increase accumulation of Rhodamine 123 in K562/A02 cells more potently than bifendate and verapamil (VRP) by inhibiting P-gp efflux function. And 8g displayed potent chemo-sensitizing effect and persisted for much longer time (>24h) compared with VRP (<6h). In addition, 8g, unlike VRP, showed no stimulation on the P-gp ATPase activity, suggesting it is not a P-gp substrate. Therefore, 8g may represent a promising lead to develop MDR reversal agents for cancer chemotherapy.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Chalcona/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/química , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chalcona/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Relação Estrutura-Atividade
20.
Artigo em Inglês | MEDLINE | ID: mdl-35805584

RESUMO

Background: Cancer patients, being immunocompromised, are at higher risk of coronavirus disease (COVID-19). The current study determines cancer patients' knowledge, attitude, perception, and impact of the COVID-19 pandemic. Method: A cross-sectional online survey was conducted in Pakistan from 1 April 2020 to 1 May 2020. The study respondents were cancer patients with ages equal to or greater than 18 years. Following a request for participation, the URL for the survey was distributed on numerous channels. Other social media platforms, including WeChat, WhatsApp, Facebook, Twitter, Instagram, Messenger, and LinkedIn, were used to increase cancer patient interaction. The questionnaire comprised five different sections such as: (1) sociodemographic information, (2) knowledge, (3) attitude, (4) perception, and (5) impact of COVID-19 on cancer patients. Descriptive medical statistics such as frequency, percentage, mean, and standard deviation were used to illustrate the demographic characteristics of the study participants. To compare mean knowledge scores with selected demographic variables, independent sample t-tests and one-way analysis of variance (ANOVA) were used, which are also practical methods in epidemiological, public health and medical research. The cut-off point for statistical significance was set at a p-value of 0.05. Results: More than 300 cancer patients were invited, of which 208 agreed to take part. The response rate was 69.33% (208/300). Gender, marital status, and employment status had a significant association with knowledge scores. Of the total recruited participants, 96% (n = 200) (p < 0.01) knew about COVID-19, and 90% were aware of general symptoms of COVID-19 disease, such as route of transmission and preventive measurements. In total, 94.5% (n = 197) (p < 0.01) were willing to accept isolation if they were infected with COVID-19, and 98% (n = 204) (p < 0.01) had reduced their use of public transportation. More than 90% (n = 188) (p < 0.01) of cancer patients were found to be practicing preventative measures such as using a face mask, keeping social distance, and avoiding handshaking and hugging. Around 94.4% (n = 196) (p < 0.01) of cancer patients had been impacted by, stopped or had changed cancer treatment during this pandemic, resulting in COVID-related anxiety and depression. Conclusion: The included cancer patients exhibited a good level of COVID-19 knowledge, awareness, positive attitude, and perception. Large-scale studies and efforts are needed to raise COVID-19 awareness among less educated and high-risk populations. The present survey indicates that mass-level effective health education initiatives are required for developing countries to improve and reduce the gap between KAP and COVID-19.


Assuntos
COVID-19 , Neoplasias , Adolescente , COVID-19/epidemiologia , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Neoplasias/epidemiologia , Paquistão/epidemiologia , Pandemias/prevenção & controle , Percepção , SARS-CoV-2 , Inquéritos e Questionários
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA