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1.
Gene ; 727: 144232, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715300

RESUMO

Colorectal cancer (CRC) is a global disease with high incidence and mortality rate. Hsp90 inhibitors induce cell death in various cancers, including CRC. However, the underlying mechanisms need to be clarified further. In this study, Caco-2 cells were treated with 0.25 µM SNX-2112, an Hsp90 inhibitor, for 48 h; subsequently, whole-transcriptome sequencing was performed. At the mRNA level in SNX-2112-treated Caco-2 cells, 1588 genes were upregulated, and 433 genes were downregulated. Six genes were found to be associated with necroptosis and apoptosis, and these 6 upregulated genes were validated by RT-qPCR. Hundred and six miRNAs were upregulated, and 48 miRNAs were downregulated in SNX-2112-treated Caco-2 cells. Eleven downregulated miRNAs were found to interact with the 6 upregulated genes. Moreover, 676 circRNAs were upregulated, and 291 circRNAs were downregulated in SNX-2112-treated Caco-2 cells. Among them, 126 circRNAs were found to be the target of the 11 downregulated miRNAs. The circRNA-miRNA-mRNA regulatory network of Hsp90 inhibitor-induced cell death in colorectal cancer was constructed. This regulatory network extends the underlying mechanism of Hsp90 and improves our understanding of Hsp90 inhibitors as potential targeted therapeutic agents.


Assuntos
Neoplasias Colorretais/genética , Redes Reguladoras de Genes/genética , Células CACO-2 , Neoplasias do Colo/genética , Neoplasias Colorretais/metabolismo , Regulação para Baixo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/genética , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , RNA/genética , RNA/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
2.
Toxicol Lett ; 320: 19-27, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31778773

RESUMO

The deleterious effects of glucocorticoids on glucose homeostasis limit their clinical use. There is substantial evidence demonstrating that islet function impaired by long-term glucocorticoids exposure is a core defect in the progression of impaired glucose tolerance to diabetes. The activity of heat-shock protein (Hsp) 90 is required to maintain the hormone-binding activity and stability of glucocorticoid receptor (GR). In the present study, Hsp90 inhibition by 17-DMAG counteracted dexamethasone-mediated inhibition of glucose-stimulated insulin secretion in isolated rat islets as well as expressions of neuropeptide Y (NPY) and somatostatin receptor 3 (SSTR3), two negative regulators of insulin secretion. Like 17-DMAG, both the pan-histone deacetylase (HDAC) inhibitor TSA and HDAC6 inhibitor Tubacin exhibited a similar action in protecting islet function against dexamethasone-induced injury, along with the downregulation of NPY and SSTR3 expressions. The hyperacetylation of Hsp90 by TSA and Tubacin disrupted its binding ability to GR and blocked dexamethasone-elicited nuclear translocation of GR in INS-1 ß-cell lines. In addition, Tubacin treatment triggered the GR protein degradation through the ubiquitin-proteasome pathway. These findings suggest that Hsp90 acetylation by inhibiting HDAC6 activity may be a potential strategy to prevent the development of steroid diabetes mellitus via alleviating glucocorticoid-impaired islet function.


Assuntos
Anilidas/farmacologia , Benzoquinonas/farmacologia , Dexametasona/toxicidade , Glucocorticoides/toxicidade , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Lactamas Macrocíclicas/farmacologia , Acetilação , Animais , Linhagem Celular , Proteínas de Choque Térmico HSP90/metabolismo , Desacetilase 6 de Histona/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional , Proteólise , Ratos Sprague-Dawley , Via Secretória , Técnicas de Cultura de Tecidos
3.
Eur J Med Chem ; 185: 111725, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655430

RESUMO

Novel dual inhibitors of histone deacetylase (HDAC) and heat-shock protein 90 (HSP90) are synthesized and evaluated. These compounds are endowed with potent HDAC and HSP90 inhibitory activities with IC50 values in nanomolar range with Compound 20 (HDAC IC50 = 194 nM; HSP90α IC50 = 153 nM) and compound 26 (HDAC IC50 = 360 nM; HSP90α IC50 = 77 nM) displaying most potent HDAC and HSP90α inhibitory activities. Both of these compounds induce HSP70 expression and down regulate HSP90 client proteins which play important roles in the regulation of survival and invasiveness in cancer cells. In addition, compounds 20 and 26 induce acetylation of α-tubulin and histone H3. Significantly, compounds 20 and 26 could effectively reduce programmed death-ligand 1 (PD-L1) expression in IFN-γ treated lung H1975 cells in a dose dependent manner. These findings suggest that dual inhibition of HDAC and HSP90 that can modulate immunosuppressive ability of tumor area may provide a better therapeutic strategy for cancer treatment in the future.


Assuntos
Anilidas/farmacologia , Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Histona Desacetilases/metabolismo , Ácidos Hidroxâmicos/farmacologia , Anilidas/síntese química , Anilidas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/biossíntese , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/química , Interferon gama/antagonistas & inibidores , Interferon gama/biossíntese , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
4.
Chem Commun (Camb) ; 55(84): 12631-12634, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31580341

RESUMO

Mitochondria targeting sensitizers are continuing to gain importance in photodynamic therapy (PDT). Members of the 90 kDa heat shock protein (Hsp90) family, including TRAP1 (Hsp75), are overexpressed in cancer cells and help to control the antiapoptotic protein activity. The present work introduces an Hsp90 inhibitor-mitochondria targeting indocyanine dye conjugate (IR-PU) for high PDT efficacy.


Assuntos
Antineoplásicos/química , Inibidores Enzimáticos/química , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Verde de Indocianina/química , Mitocôndrias/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Corantes Fluorescentes/química , Humanos , Verde de Indocianina/farmacologia , Camundongos , Camundongos Nus , Transplante de Neoplasias , Imagem Óptica/métodos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Oxigênio Singlete/metabolismo
5.
Eur J Med Chem ; 183: 111699, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31561045

RESUMO

The recent burst of explorations on heat shock protein 90 (HSP90) in virus research supports its emergence as a promising target to overcome the drawbacks of current antiviral therapeutic regimen. In continuation of our efforts towards the discovery of novel anti-retroviral molecules, we designed, synthesized fifteen novels 2-isoxazol-3-yl-acetamide based compounds (2a-o) followed by analysis of their anti-HIV activity and cytotoxicity studies. 2a-b, 2e, 2j, and 2l-m were found to be active with inhibitory potentials >80% at their highest non-cytotoxic concentration (HNC). Further characterization of anti-HIV activity of these molecules suggests that 2l has ∼3.5 fold better therapeutic index than AUY922, the second generation HSP90 inhibitor. The anti-HIV activity of 2l is a cell type, virus isolate and viral load independent phenomena. Interestingly, 2l does not significantly modulate viral enzymes like Reverse Transcriptase (RT), Integrase (IN) and Protease (PR) as compared to their known inhibitors in a cell free in vitro assay system at its HNC. Further, 2l mediated inhibition of HSP90 attenuates HIV-1 LTR driven gene expression. Taken together, structural rationale, modeling studies and characterization of biological activities suggest that this novel scaffold can attenuate HIV-1 replication significantly within the host and thus opens a new horizon to develop novel anti-HIV therapeutic candidates.


Assuntos
Acetamidas/farmacologia , Androstenóis/farmacologia , Fármacos Anti-HIV/farmacologia , Descoberta de Drogas , HIV-1/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Acetamidas/síntese química , Acetamidas/química , Androstenóis/síntese química , Androstenóis/química , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Relação Dose-Resposta a Droga , HIV-1/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
6.
Int J Mol Sci ; 20(18)2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527404

RESUMO

Heat Shock Protein 90 (Hsp90) chaperone interacts with a broad range of client proteins involved in cancerogenesis and cancer progression. However, Hsp90 inhibitors were unsuccessful as anticancer agents due to their high toxicity, lack of selectivity against cancer cells and extrusion by membrane transporters responsible for multidrug resistance (MDR) such as P-glycoprotein (P-gp). Recognizing the potential of new compounds to inhibit P-gp function and/or expression is essential in the search for effective anticancer drugs. Eleven Hsp90 inhibitors containing an isoxazolonaphtoquinone core were synthesized and evaluated in two MDR models comprised of sensitive and corresponding resistant cancer cells with P-gp overexpression (human non-small cell lung carcinoma and colorectal adenocarcinoma). We investigated the effect of Hsp90 inhibitors on cell growth inhibition, P-gp activity and P-gp expression. Structure-activity relationship analysis was performed in respect to cell growth and P-gp inhibition. Compounds 5, 7, and 9 directly interacted with P-gp and inhibited its ATPase activity. Their potential P-gp binding site was identified by molecular docking studies. In addition, these compounds downregulated P-gp expression in MDR colorectal carcinoma cells, showed good relative selectivity towards cancer cells, while compound 5 reversed resistance to doxorubicin and paclitaxel in concentration-dependent manner. Therefore, compounds 5, 7 and 9 could be promising candidates for treating cancers with P-gp overexpression.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/genética , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Relação Estrutura-Atividade
7.
Comput Biol Chem ; 83: 107113, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31493740

RESUMO

Breast cancer is one of the major impediments affecting women globally. The ATP-dependant heat shock protein 90 (Hsp90) forms the central component of molecular chaperone machinery that predominantly governs the folding of newly synthesized peptides and their conformational maturation. It regulates the stability and function of numerous client proteins that are frequently upregulated and/or mutated in cancer cells, therefore, making Hsp90 inhibition a promising therapeutic strategy for the development of new efficacious drugs to treat breast cancer. In the present in silico investigation, a structure-based pharmacophore model was generated with hydrogen bond donor, hydrogen bond acceptor and hydrophobic features complementary to crucial residues Ala55, Lys58, Asp93, Ile96, Met98 and Thr184 directed at inhibiting the ATP-binding activity of Hsp90. Subsequently, the phytochemical dataset of 3210 natural compounds was screened to retrieve the prospective inhibitors after rigorous validation of the model pharmacophore. The retrieved 135 phytocompounds were further filtered by drug-likeness parameters including Lipinski's rule of five and ADMET properties, then investigated via molecular docking-based scoring. Molecular interactions were assessed using Genetic Optimisation for Ligand Docking program for 95 drug-like natural compounds against Hsp90 along with two clinical drugs as reference compounds - Geldanamycin and Radicicol. Docking studies revealed three phytochemicals are better than the investigated clinical drugs. The reference and hit compounds with dock scores of 48.27 (Geldanamycin), 40.90 (Radicicol), 73.04 (Hit1), 72.92 (Hit2) and 68.12 (Hit3) were further validated for their binding stability through molecular dynamics simulations. We propose that the non-macrocyclic scaffolds of three identified phytochemicals might aid in the development of novel therapeutic candidates against Hsp90-driven cancers.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Modelos Moleculares , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Relação Estrutura-Atividade
8.
Arch Pharm (Weinheim) ; 352(10): e1900063, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31411362

RESUMO

A series of novel pyrazolyl 2-aminopyrimidine derivatives (7a-t) were designed based on scaffold hopping techniques, synthesized and biologically evaluated for their HSP90 inhibition and anticancer activity. Several compounds exhibited potent HSP90 inhibition with IC50 values less than that of the reference standard 17-AAG (1.25 µM). The most potent compound 7t displayed excellent HSP90 inhibition with an IC50 of 20 nM and in vitro antiproliferative potential against three cancer cell lines (IC50 < 5 µM). 7t also induced dose dependent degradation of client proteins (pHER2 and pERK1/2) in Western blot analysis. Several structural features of 7p-t oriented the molecules to retain all the essential binding interactions with HSP90, as observed by rationalized docking studies. Therefore, the para-nitrophenyl ring on the central pyrazole ring along with the 2-amino group on the pyrimidine ring are the crucial features in the development of novel HSP90 inhibitors based on this scaffold for targeted anticancer therapy.


Assuntos
Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Desenho de Drogas , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Pirazóis/química , Pirimidinas/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Humanos , Concentração Inibidora 50 , Células MCF-7 , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirimidinas/química , Pirimidinas/farmacologia , Relação Estrutura-Atividade
9.
Biomed Res ; 40(4): 169-178, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413238

RESUMO

Migration of osteoblasts to the sites resorbed by osteoclasts is an essential step in bone remodeling. However, the exact mechanism of osteoblast migration is still not known. We have shown that platelet-derived growth factor (PDGF)-BB induces the migration of osteoblast-like MC3T3-E1 cells through the activation of p38 mitogen-activated protein (MAP) kinase, c-Jun N-terminal kinase (JNK) and p44/p42 MAP kinase. Evidence is accumulating that heat shock protein 90 (HSP90) acts as a central regulator of proteostasis under stress conditions and physiological cell functions. In the present study, using transwell cell migration assay and wound-healing assay, we investigated the involvement of HSP90 in the PDGF-BB-stimulated migration of MC3T3-E1 cells, and the underlying signaling mechanism estimated by Western blot analyses. Onalespib, an HSP90 inhibitor, significantly reduced the PDGF-BB-stimulated migration evaluated by the two types of migration assays. The cell migration was also suppressed by geldanamycin, another type of HSP90 inhibitor. Onalespib markedly attenuated the PDGF-BB-elicited phosphorylation of p44/p42 MAP kinase without affecting that of p38 MAP kinase or JNK. In addition, the phosphorylation of p44/p42 MAP kinase by PDGF-BB was reduced by geldanamycin. Taken together, these results strongly suggest that HSP90 inhibitors suppress the PDGF-BB-induced osteoblast migration through the attenuation of p44/p42 MAP kinase activity.


Assuntos
Becaplermina/farmacologia , Benzamidas/farmacologia , Benzoquinonas/farmacologia , Movimento Celular/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Isoindóis/farmacologia , Lactamas Macrocíclicas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Osteoblastos/metabolismo , Animais , Linhagem Celular , Proteínas de Choque Térmico HSP90/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos
10.
Biochimie ; 165: 206-209, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31404589

RESUMO

Ongoing efforts are oriented towards the development of novel therapeutic agents to repress lung hyperpermeability responses due to inflammation. The endothelial barrier dysfunction triggered by such events, may eventually lead to severe cardiovascular complications, such as the Acute Respiratory Distress Syndrome. Hsp90 inhibitors are anticancer compounds, associated with strong anti-inflammatory responses in the endothelium. Our latest observations in experimental models of Acute Lung Injury suggest that P53 orchestrates, at least in part, such activities. Remarkably, both Hsp90 inhibition and P53 induction are associated with the activation of the Unfolded Protein Response element. The purpose of the current manuscript, is to introduce the hypotheses that UPR induction protects the vasculature against inflammation.


Assuntos
Lesão Pulmonar Aguda , Endotélio Vascular/patologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Síndrome do Desconforto Respiratório do Adulto , Proteína Supressora de Tumor p53/fisiologia , Resposta a Proteínas não Dobradas/fisiologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Animais , Permeabilidade Capilar , Células Cultivadas , Humanos , Inflamação/metabolismo , Camundongos , Síndrome do Desconforto Respiratório do Adulto/tratamento farmacológico , Síndrome do Desconforto Respiratório do Adulto/metabolismo
11.
Chemphyschem ; 20(21): 2759-2766, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31460692

RESUMO

This paper describes the excellent performance of a newly developed scoring function (SF), based on the semiempirical QM (SQM) PM6-D3H4X method combined with the conductor-like screening implicit solvent model (COSMO). The SQM/COSMO, Amber/GB and nine widely used SFs have been evaluated in terms of ranking power on the HSP90 protein with 72 biologically active compounds and 4469 structurally similar decoys. Among conventional SFs, the highest early and overall enrichment measured by EF1 and AUC% obtained using single-scoring-function ranking has been found for Glide SP and Gold-ASP SFs, respectively (7, 75 % and 3, 76 %). The performance of other standard SFs has not been satisfactory, mostly even decreasing below random values. The SQM/COSMO SF, where P-L structures were optimised at the advanced Amber level, has resulted in a dramatic enrichment increase (47, 98 %), almost reaching the best possible receiver operator characteristic (ROC) curve. The best SQM frame thus inserts about seven times more active compounds into the selected dataset than the best standard SF.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Teoria Quântica , Proteínas de Choque Térmico HSP90/metabolismo , Ligantes , Modelos Moleculares , Curva ROC , Termodinâmica
12.
J Therm Biol ; 84: 1-7, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31466741

RESUMO

Heat can trigger testicular damage and impair fertility. Leydig cells produce testosterone in response to stimulation by luteinizing hormone (LH), which induces Ca2+ entry and K+ efflux through ion channels in their plasma membrane. Considering that mechanisms coordinating the Leydig cell responses to hyperthermic stress remain unclear; the present study analyzed the effects of heat stress (HS, 43°C, 15 min) and inhibition of Hsp90 on T-type calcium currents and voltage-dependent potassium currents (VKC) in mice Leydig cells. Results show that HS reduced the VKC steady state currents at +80 mV (45.3%) and maximum conductance (71.5%), as well as increased the activation time constant (31.7%) and the voltage for which half the channels are open (30%). Hsp90 inhibition did not change the VKC currents. T-type calcium currents were not affected by HS or Hsp90 inhibition. In conclusion, HS can slow the activation, reduce the currents and voltage dependence of the VKC, suggesting a possible role of these currents in the response to hyperthermic stress in Leydig cells.


Assuntos
Canais de Cálcio Tipo T/fisiologia , Proteínas de Choque Térmico HSP90/fisiologia , Resposta ao Choque Térmico/fisiologia , Células Intersticiais do Testículo/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Animais , Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Temperatura Alta , Lactamas Macrocíclicas/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Camundongos
13.
Org Biomol Chem ; 17(28): 6854-6859, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31263819

RESUMO

The anti-malarial drug artemisinin (ART) possesses potent anti-inflammatory activity, yet its underlying mechanism of action has remained elusive. Here we employed quantitative chemical proteomics to in situ profile the cellular targets of ART and identified heat shock protein 90 (HSP90) as a direct target. Further study revealed that ART suppressed the production of nitric oxide (NO) in macrophages via inhibiting the interaction between HSP90 and inducible NO synthase (iNOS).


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Artemisininas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteômica , Animais , Anti-Inflamatórios não Esteroides/química , Artemisininas/química , Células Cultivadas , Proteínas de Choque Térmico HSP90/análise , Hibridização in Situ Fluorescente , Camundongos , Células RAW 264.7
14.
Biochim Biophys Acta Mol Cell Res ; 1866(10): 1544-1555, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31326539

RESUMO

Plasma membrane transporter SLC6A14 transports all neutral and basic amino acids in a Na/Cl - dependent way and it is up-regulated in many types of cancer. Mass spectrometry analysis of overexpressed SLC6A14-associated proteins identified, among others, the presence of cytosolic heat shock proteins (HSPs) and co-chaperones. We detected co-localization of overexpressed and native SLC6A14 with HSP90-beta and HSP70 (HSPA14). Proximity ligation assay confirmed a direct interaction of overexpressed SLC6A14 with both HSPs. Treatment with radicicol and VER155008, specific inhibitors of HSP90 and HSP70, respectively, attenuated these interactions and strongly reduced transporter presence at the cell surface, what resulted from the diminished level of the total transporter protein. Distortion of SLC6A14 proper folding by both HSPs inhibitors directed the transporter towards endoplasmic reticulum-associated degradation pathway, a process reversed by the proteasome inhibitor - bortezomib. As demonstrated in an in vitro ATPase assay of recombinant purified HSP90-beta, the peptides corresponding to C-terminal amino acid sequence following the last transmembrane domain of SLC6A14 affected the HSP90-beta activity. These results indicate that a plasma membrane protein folding can be controlled not only by chaperones in the endoplasmic reticulum, but also those localized in the cytosol.


Assuntos
Sistemas de Transporte de Aminoácidos/metabolismo , Membrana Celular/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Transporte Proteico/fisiologia , Adenosina Trifosfatases/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Biotinilação , Bortezomib/farmacologia , Proteínas de Transporte/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Citosol/metabolismo , Retículo Endoplasmático/metabolismo , Degradação Associada com o Retículo Endoplasmático , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/genética , Humanos , Células MCF-7 , Macrolídeos/farmacologia , Chaperonas Moleculares/metabolismo , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Dobramento de Proteína , Transporte Proteico/efeitos dos fármacos , Nucleosídeos de Purina/farmacologia
15.
Life Sci ; 232: 116672, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336120

RESUMO

AIMS: Obesity is not only associated with metabolic diseases but is also a symptom of menopause in women. To date, there are no effective drugs for the management of obesity, and it is important to find new agents with fewer side effects, for the treatment of obesity. This study aimed to determine the anti-obesity effect of 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG), a heat shock protein 90 (Hsp90) inhibitor, and its underlying mechanism in rats with ovariectomy-induced obesity. MAIN METHODS: Ovariectomy (Ovx) rats were treated with 17-DMAG (1 mg kg-1, intraperitoneally) for eight weeks from one week after surgery. The body weight, food intake, locomotor activity, adipogenic- and autophagy-related protein expression in white adipose tissue (WAT) and plasma triglyceride (TG) levels were measured in sham and Ovx rats. KEY FINDINGS: Compared with sham rats, Ovx rats showed increased weight gain, food intake, WAT mass, TG levels, adipogenic protein expression, and decreased locomotor activity. Furthermore, autophagy-related proteins and Foxo3a of WAT were significantly increased in Ovx rats. However, with the exclusion of increased food intake, the changes induced by Ovx were all reversed in 17-DMAG-treated Ovx rats. In addition, the expression of Hsp70 and phosphorylation of Akt increased in 17-DMAG-treated Ovx rats. SIGNIFICANCE: These results suggest that 17-DMAG significantly ameliorated obesity induced by Ovx, and this phenomenon is accompanied by the downregulation of adipogenic-related and autophagy-related proteins as well as the upregulation of Akt-phosphorylation and Hsp70 expression. Therefore, 17-DMAG may be a potential agent for preventing or treating obesity in postmenopausal women.


Assuntos
Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Obesidade/etiologia , Obesidade/prevenção & controle , Ovariectomia/efeitos adversos , Adipogenia , Tecido Adiposo/metabolismo , Animais , Autofagia , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Locomoção/efeitos dos fármacos , Ratos
16.
Curr Pharm Des ; 25(8): 849-855, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244417

RESUMO

Heat shock protein 90 (Hsp90) plays an essential role in various physiological and pathological processes. It activates client proteins to participate in tumor progression. Blocking Hsp90 could enable effective antitumor effects in many tumor types, such as multiple myeloma and colon cancer. Recently, it has motivated an interest in Hsp90 inhibitors that bind to the N-terminal or C-terminal ATP pocket as antitumor drugs. We reviewed the data from experimental and clinical trials on Hsp90 inhibitors in the treatment of different malignancies to explore and summarize their antitumor mechanisms.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Humanos
17.
Food Chem Toxicol ; 132: 110645, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31254591

RESUMO

The flavonolignan silibinin is the major component of the extract isolated from the seeds of the milk thistle (Silybum marianum). Herein, we performed an in silico analysis focusing on the molecular docking of the putative atomic interactions between silibinin and heat shock protein 90 (Hsp90), an adenosine triphosphate-dependent molecular chaperone differentially expressed in response to microenvironmental stress. Time-resolved fluorescence resonance energy transfer was employed to measure the capacity of silibinin to inhibit Hsp90 binding to other co-chaperones with enzymatic activity. Whereas silibinin is predicted to interact with several pockets in the C-terminal domain (CTD) of Hsp90α and ß, its highest-ranking docked poses significantly overlap with those of novobiocin, a well-characterized Hsp90 CTD-targeting inhibitor. The net biochemical effect of silibinin was to inhibit the efficiency of Hsp90α/ß CTD binding to its co-chaperone PPID/cyclophilin D in the low millimolar range, equivalent to that observed for novobiocin. The hepatotoxicant behavior of silibinin solely occurred at concentrations several thousand times higher than those of the Hsp90 N-terminal inhibitor geldanamycin. Silibinin might be viewed as a non-hepatotoxic, novobiocin-like Hsp90 inhibitor that binds the CTD to induce changes in Hsp90 conformation and alter Hsp90-co-chaperone-client interactions, thereby providing new paths to developing safe and efficacious Hsp90 inhibitors.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Silibina/metabolismo , Silibina/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Ciclofilinas/metabolismo , Proteínas de Choque Térmico HSP90/química , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Novobiocina/química , Novobiocina/metabolismo , Ligação Proteica , Multimerização Proteica/efeitos dos fármacos , Silibina/química , Superóxidos/metabolismo
18.
Molecules ; 24(11)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163701

RESUMO

Hsp90 (Heat shock protein 90) is involved in various processes in cancer occurrence and development, and therefore represents a promising drug target for cancer therapy. In this work, a virtual screening strategy was employed, leading to the identification of a series of compounds bearing a scaffold of 1,3-dibenzyl-2-aryl imidazolidine as novel Hsp90 inhibitors. Compound 4a showed the highest binding affinity to Hsp90α (IC50 = 12 nM) in fluorescence polarization (FP) competition assay and the strongest anti-proliferative activity against human breast adenocarcinoma cell line (MCF-7) and human lung epithelial cell line (A549) with IC50 values of 21.58 µM and 31.22 µM, respectively. Western blotting assays revealed that these novel Hsp90 inhibitors significantly down-regulated the expression level of Her2, a client protein of Hsp90, resulting in the cytotoxicity of these novel Hsp90 inhibitors. The molecular docking study showed that these novel Hsp90 inhibitors bound to the adenosine triphosphate (ATP) binding site at the N-terminus of Hsp90. Furthermore, structure-activity relationship studies indicated that the N-benzyl group is important for the anti-cancer activity of 1,3-dibenzyl-2-aryl imidazolidines.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Imidazolidinas/química , Imidazolidinas/farmacologia , Células A549 , Proliferação de Células/efeitos dos fármacos , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Concentração Inibidora 50 , Células MCF-7 , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Interface Usuário-Computador
19.
Mol Pharmacol ; 96(2): 168-179, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31175180

RESUMO

Molecular chaperone heat shock protein 90 (HSP90) is involved in oncogenic signaling pathways including epithelial-mesenchymal transition (EMT), a key process in tumor initiation, progression, metastasis, and chemoresistance. The molecular mechanisms underlying the involvement of HSP90 in EMT are still under investigation. In this study, we identified a previously unrecognized role of HSP90 in cooperating with signal transducer and activator of transcription 3 (STAT3) to regulate TWIST1 transcription in cancer cells. The HSP90 inhibitor 17-N-allylamino-17-demethoxygeldanamycin suppressed TWIST1 mRNA expression and promoter activity in epithelial ovarian cancer, renal clear cell cancer, and nasopharyngeal cancer cell lines. The interactions between HSP90 and transcription factors were visualized in cancer cell lines and tumor tissues using proximity ligation assays. Our findings reveal that HSP90 promotes the binding of STAT3 to the TWIST1 promoter, leading to the transcription of TWIST1. The inhibition of HSP90 downregulates STAT3 activity and TWIST1 transcription, thereby suppressing EMT and potentially inhibiting tumor progression, metastasis, and chemoresistance in different types of cancers. SIGNIFICANCE STATEMENT: Our study provides new evidence that HSP90 promotes EMT through enhancing TWIST1 transcription, which can be suppressed by HSP90 inhibitors. The HSP90 inhibitor inhibits EMT, thus potentially slowing down tumor growth, invasion, dissemination, metastasis, and drug resistance. These findings will hopefully pave the way for new therapeutic opportunities to target EMT and metastasis using HSP90 inhibitors.


Assuntos
Benzoquinonas/farmacologia , Neoplasias Renais/genética , Lactamas Macrocíclicas/farmacologia , Neoplasias Nasofaríngeas/genética , Proteínas Nucleares/genética , Neoplasias Ovarianas/genética , Fator de Transcrição STAT3/metabolismo , Proteína 1 Relacionada a Twist/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/metabolismo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas/efeitos dos fármacos , Análise Serial de Tecidos , Transcrição Genética/efeitos dos fármacos
20.
Eur J Med Chem ; 178: 48-63, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176095

RESUMO

The ninety kilo Dalton molecular weight heat shock protein (Hsp90) is an attractive target for the discovery of novel anticancer agents. Several strategies have been employed for the development of inhibitors against this polypeptide. The most successful strategy is targeting the N-terminal ATP binding region of the chaperone. However, till date not a single molecule reached Phase-IV of clinical trials from this class of Hsp90 inhibitors. The other approach is to target the Cterminal region of the protein. The success with this approach has been limited due to lack of well-defined ligand binding pocket in this terminal. The other promising strategy is to prevent the interaction of client proteins/co-chaperones with Hsp90 protein, i.e., protein-protein interaction inhibitors of Hsp90. The review focuses on advantage of this approach along with the recent advances in the discovery of inhibitors by following this strategy. Additionally, the biology of the client protein/co-chaperone binding site of Hsp90 is also discussed.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Neoplasias/tratamento farmacológico , Ligação Proteica/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSP90/química , Humanos
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