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1.
J Cell Sci ; 133(9)2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32184263

RESUMO

Under metabolic stress, cellular components can assemble into distinct membraneless organelles for adaptation. One such example is cytidine 5'-triphosphate synthase (CTPS, for which there are CTPS1 and CTPS2 forms in mammals), which forms filamentous structures under glutamine deprivation. We have previously demonstrated that histidine (His)-mediated methylation regulates the formation of CTPS filaments to suppress enzymatic activity and preserve the CTPS protein under glutamine deprivation, which promotes cancer cell growth after stress alleviation. However, it remains unclear where and how these enigmatic structures are assembled. Using CTPS-APEX2-mediated in vivo proximity labeling, we found that synaptosome-associated protein 29 (SNAP29) regulates the spatiotemporal filament assembly of CTPS along the cytokeratin network in a keratin 8 (KRT8)-dependent manner. Knockdown of SNAP29 interfered with assembly and relaxed the filament-induced suppression of CTPS enzymatic activity. Furthermore, APEX2 proximity labeling of keratin 18 (KRT18) revealed a spatiotemporal association of SNAP29 with cytokeratin in response to stress. Super-resolution imaging suggests that during CTPS filament formation, SNAP29 interacts with CTPS along the cytokeratin network. This study links the cytokeratin network to the regulation of metabolism by compartmentalization of metabolic enzymes during nutrient deprivation.


Assuntos
Carbono-Nitrogênio Ligases , Histidina , Animais , Citidina Trifosfato , Histidina/genética , Queratinas
2.
Molecules ; 26(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34443427

RESUMO

Pterostilbene, a natural metabolite of resveratrol, has been indicated as a potent anticancer molecule. Recently, several pterostilbene derivatives have been reported to exhibit better anticancer activities than that of the parent pterostilbene molecule. In the present study, a series of pterostilbene derivatives were designed and synthesized by the hybridization of pterostilbene, chalcone, and cinnamic acid. The cytotoxic effect of these hybrid molecules was determined using two oral cancer cell lines, HSC-3 and OECM-1. (E)-3-(2-((E)-4-Hydroxystyryl)-4,6-dimethoxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one (4d), with IC50 of 16.38 and 18.06 µM against OECM-1 and HSC-3, respectively, was selected for further anticancer mechanism studies. Results indicated that compound 4d effectively inhibited cell proliferation and induced G2/M cell cycle arrest via modulating p21, cyclin B1, and cyclin A2. Compound 4d ultimately induced cell apoptosis by reducing the expression of Bcl-2 and surviving. In addition, cleavage of PARP and caspase-3 were enhanced following the treatment of compound 4d with increased dose. To conclude, a number of pterostilbene derivatives were discovered to possess potent anticancer potentials. Among them, compound 4d was the most active, more active than the parent pterostilbene.


Assuntos
Antineoplásicos/farmacologia , Chalcona/farmacologia , Estilbenos/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chalcona/química , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Poli(ADP-Ribose) Polimerases/metabolismo , Estilbenos/química , Relação Estrutura-Atividade
3.
Q J Nucl Med Mol Imaging ; 64(4): 393-399, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30160089

RESUMO

BACKGROUND: 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography (18F-FDG PET) has the potential to detect various types of cancers, including thyroid cancer (TC), at a potentially curable stage. Increased uptake of 18F-FDG was observed in anaplastic and poorly differentiated thyroid cancer cells, and PET-positive tumors are more likely to be resistant to 131I treatment. As cancer stem cells (CSCs) possess a dedifferentiated phenotype and are resistant to many anticancer therapies, we hypothesized that the expression of CSC-related markers is correlated with the ability of tumor cells in TC to uptake FDG. METHODS: The present study cohort included 12 patients with TC, who underwent 18F-FDG PET/CT imaging before surgery. Quantitative polymerase chain reaction (QPCR) and immunohistochemical (IHC) staining were performed to analyze the expression patterns of gene markers related to embryonic stem (ES) cells and CSCs in TC. RESULTS: The mRNA expression levels of CSC- (CD133 and CD44) and ES-related genes (Oct4 and Nanog) were higher in TC tissue than in normal thyroid tissue, whereas the mRNA expression levels of thyroid-specific genes (Tg, TSHR, and TTF1) were higher in normal thyroid tissue than in TC tissue. There was a positive and statistically significant correlation between FDG uptake (SUVmax) of tumor and relative mRNA levels of CD133, CD44, Oct4, and Nanog. The IHC results demonstrated that CD133 and Nanog were expressed in TC tissue but not in normal thyroid tissue, however, CD44 expression was observed in both TC and normal thyroid tissue. Comparisons of the clinicopathological parameters between TC tissues with low and high SUVmax demonstrated significant differences in protein level of CD133 but not in that of Nanog. CONCLUSIONS: The pre-therapeutic tumor SUVmax obtained from 18F-FDG PET/CT may be a potential predictor for evaluating the proportion of CSC population in individual patients with TC.


Assuntos
Fluordesoxiglucose F18/química , Células-Tronco Neoplásicas/efeitos da radiação , Compostos Radiofarmacêuticos/química , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/tratamento farmacológico , Antígeno AC133/metabolismo , Transporte Biológico , Diferenciação Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Fluordesoxiglucose F18/farmacologia , Humanos , Receptores de Hialuronatos/metabolismo , Radioisótopos de Índio/química , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , RNA Mensageiro , Receptores da Tireotropina/metabolismo , Glândula Tireoide/citologia , Distribuição Tecidual , Tomografia Computadorizada por Raios X , Fator Trefoil-1/metabolismo
4.
Alcohol Clin Exp Res ; 42(2): 329-337, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29205407

RESUMO

BACKGROUND: Ethanol (EtOH) intoxication inhibits glucose transport and decreases overall brain glucose metabolism; however, humans with long-term EtOH consumption were found to have a significant increase in [1-11 C]-acetate uptake in the brain. The relationship between the cause and effect of [1-11 C]-acetate kinetics and acute/chronic EtOH intoxication, however, is still unclear. METHODS: [1-11 C]-acetate positron emission tomography (PET) with dynamic measurement of K1 and k2 rate constants was used to investigate the changes in acetate metabolism in different brain regions of rats with acute or chronic EtOH intoxication. RESULTS: PET imaging demonstrated decreased [1-11 C]-acetate uptake in rat brain with acute EtOH intoxication, but this increased with chronic EtOH intoxication. Tracer uptake rate constant K1 and clearance rate constant k2 were decreased in acutely intoxicated rats. No significant change was noted in K1 and k2 in chronic EtOH intoxication, although 6 of 7 brain regions showed slightly higher k2 than baseline. These results indicate that acute EtOH intoxication accelerated acetate transport and metabolism in the rat brain, whereas chronic EtOH intoxication status showed no significant effect. CONCLUSIONS: In vivo PET study confirmed the modulatory role of EtOH, administered acutely or chronically, in [1-11 C]-acetate kinetics and metabolism in the rat brain. Acute EtOH intoxication may inhibit the transport and metabolism of acetate in the brain, whereas chronic EtOH exposure may lead to the adaptation of the rat brain to EtOH in acetate utilization. [1-11 C]-acetate PET imaging is a feasible approach to study the effect of EtOH on acetate metabolism in rat brain.


Assuntos
Acetatos/metabolismo , Intoxicação Alcoólica/metabolismo , Alcoolismo/metabolismo , Encéfalo/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Intoxicação Alcoólica/diagnóstico por imagem , Alcoolismo/diagnóstico por imagem , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Radioisótopos de Carbono , Glucose/metabolismo , Masculino , Tomografia por Emissão de Pósitrons , Ratos
5.
Proc Natl Acad Sci U S A ; 111(1): 279-84, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24344305

RESUMO

JMJD5, a Jumonji C domain-containing dioxygenase, is important for embryonic development and cancer growth. Here, we show that JMJD5 is up-regulated by hypoxia and is crucial for hypoxia-induced cell proliferation. JMJD5 interacts directly with pyruvate kinase muscle isozyme (PKM)2 to modulate metabolic flux in cancer cells. The JMJD5-PKM2 interaction resides at the intersubunit interface region of PKM2, which hinders PKM2 tetramerization and blocks pyruvate kinase activity. This interaction also influences translocation of PKM2 into the nucleus and promotes hypoxia-inducible factor (HIF)-1α-mediated transactivation. JMJD5 knockdown inhibits the transcription of the PKM2-HIF-1α target genes involved in glucose metabolism, resulting in a reduction of glucose uptake and lactate secretion in cancer cells. JMJD5, along with PKM2 and HIF-1α, is recruited to the hypoxia response element site in the lactate dehydrogenase A and PKM2 loci and mediates the recruitment of the latter two proteins. Our data uncover a mechanism whereby PKM2 can be regulated by factor-binding-induced homo/heterooligomeric restructuring, paving the way to cell metabolic reprogram.


Assuntos
Proteínas de Transporte/metabolismo , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Histona Desmetilases/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas de Membrana/metabolismo , Hormônios Tireóideos/metabolismo , Transporte Ativo do Núcleo Celular , Sítio Alostérico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Feminino , Glicólise , Células HEK293 , Células HeLa , Humanos , Hipóxia , Isoenzimas/metabolismo , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5 , Ácido Láctico/metabolismo , Células MCF-7 , Neoplasias/metabolismo , Ligação Proteica , Estrutura Quaternária de Proteína , Ativação Transcricional , Proteínas de Ligação a Hormônio da Tireoide
6.
Mol Pharm ; 13(3): 784-94, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26796063

RESUMO

CUDC-907 is a novel, dual-acting small molecule compound designed to simultaneously inhibit the activity of histone deacetylase (HDAC) and phosphatidylinositol 3-kinase (PI3K). Treatment with CUDC-907 led to sustained inhibition of HDAC and PI3K activity, inhibition of RAF-MEK-MAPK signaling pathway, and inhibition of cancer cell growth. CUDC-907 is currently under evaluation in phase I clinical trials in patients with lymphoma or multiple myeloma, and in patients with advanced solid tumors. However, the risk of developing acquired resistance to CUDC-907 can present a significant therapeutic challenge to clinicians in the future and should be investigated. The overexpression of ATP-binding cassette (ABC) drug transporter ABCB1, ABCC1, or ABCG2 is one of the most common mechanisms of developing multidrug resistance (MDR) in cancers and a major obstacle in chemotherapy. In this study, we reveal that ABCG2 reduces the intracellular accumulation of CUDC-907 and confers significant resistance to CUDC-907, which leads to reduced activity of CUDC-907 to inhibit HDAC and PI3K in human cancer cells. Moreover, although CUDC-907 affects the transport function of ABCG2, it was not potent enough to reverse drug resistance mediated by ABCG2 or affect the expression level of ABCG2 in human cancer cells. Taken together, our findings indicate that ABCG2-mediated CUDC-907 resistance can have serious clinical implications and should be further investigated. More importantly, we demonstrate that the activity of CUDC-907 in ABCG2-overexpressing cancer cells can be restored by inhibiting the function of ABCG2, which provides support for the rationale of combining CUDC-907 with modulators of ABCG2 to improve the pharmacokinetics and efficacy of CUDC-907 in future treatment trials.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Histona Desacetilases/química , Morfolinas/farmacologia , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Pirimidinas/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Histona Desacetilases/metabolismo , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
7.
Biochim Biophys Acta ; 1843(11): 2513-27, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25014165

RESUMO

The PAK2/ßPIX/GIT1 (p21-activated kinase 2/PAK-interacting exchange factor-ß/G protein-coupled receptor kinase-interactor 1) complex has been shown to distribute to both membrane ruffles and focal adhesions of cells, where it plays an important role in regulating focal adhesion turnover. However, the detailed mechanism underlying this regulation is largely unknown. We previously reported that MYO18Aα interacts via its carboxyl terminus with the PAK2/ßPIX/GIT1 complex through direct binding to ßPIX, and that knockdown of MYO18Aα in epithelial cells causes accumulation of the complex in focal adhesions and decreased cell migration ability (Hsu et al., 2010). The current study characterized the detailed MYO18Aα-ßPIX interaction mechanism and the biological significance of this interaction. We found that deletion of the carboxyl-terminal globular domain of MYO18Aα profoundly altered the cellular localization of ßPIX and inhibited cell migration. ßPIX interacts through its most carboxyl-terminus, PAWDETNL (639-646), with MYO18Aα and partially colocalized with MYO18Aα in membrane ruffles of cells, whereas ßPIX(1-638), a mutant with deletion of PAWDETNL, accumulated in focal adhesions. Both focal adhesion numbers and area in ßPIX(1-638)-expressing cells were greater than those in cells expressing wild-type ßPIX(FL). Further experiments using deletion mutants of MYO18A and ßPIX showed that disruption of MYO18A-ßPIX interaction not only impaired cell motility but also decreased Rac1 activity. Collectively, our data unravel the interaction regions between MYO18A and ßPIX and provide evidence for the critical role of this interaction in regulating cellular localization of ßPIX, Rac1 activity, and adhesion and migration in epithelial cells.

8.
PLoS Pathog ; 9(1): e1003100, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23382671

RESUMO

During disease progression to AIDS, HIV-1 infected individuals become increasingly immunosuppressed and susceptible to opportunistic infections. It has also been demonstrated that multiple subsets of dendritic cells (DC), including DC-SIGN⁺ cells, become significantly depleted in the blood and lymphoid tissues of AIDS patients, which may contribute to the failure in initiating effective host immune responses. The mechanism for DC depletion, however, is unclear. It is also known that vast quantities of viral envelope protein gp120 are shed from maturing HIV-1 virions and form circulating immune complexes in the serum of HIV-1-infected individuals, but the pathological role of gp120 in HIV-1 pathogenesis remains elusive. Here we describe a previously unrecognized mechanism of DC death in chronic HIV-1 infection, in which ligation of DC-SIGN by gp120 sensitizes DC to undergo accelerated apoptosis in response to a variety of activation stimuli. The cultured monocyte-derived DC and also freshly-isolated DC-SIGN⁺ blood DC that were exposed to either cross-linked recombinant gp120 or immune-complex gp120 in HIV⁺ serum underwent considerable apoptosis after CD40 ligation or exposure to bacterial lipopolysaccharide (LPS) or pro-inflammatory cytokines such as TNFα and IL-1ß. Furthermore, circulating DC-SIGN⁺ DC that were isolated directly from HIV-1⁺ individuals had actually been pre-sensitized by serum gp120 for activation-induced exorbitant apoptosis. In all cases the DC apoptosis was substantially inhibited by DC-SIGN blockade. Finally, we showed that accelerated DC apoptosis was a direct consequence of excessive activation of the pro-apoptotic molecule ASK-1 and transfection of siRNA against ASK-1 significantly prevented the activation-induced excessive DC death. Our study discloses a previously unknown mechanism of immune modulation by envelope protein gp120, provides new insights into HIV immunopathogenesis, and suggests potential therapeutic approaches to prevent DC depletion in chronic HIV infection.


Assuntos
Apoptose/fisiologia , Moléculas de Adesão Celular/metabolismo , Células Dendríticas/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , Lectinas Tipo C/metabolismo , MAP Quinase Quinase Quinase 5/metabolismo , Receptores de Superfície Celular/metabolismo , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD40/imunologia , Moléculas de Adesão Celular/imunologia , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/patologia , Inativação Gênica , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/sangue , Infecções por HIV/imunologia , Interações Hospedeiro-Patógeno , Humanos , Lectinas Tipo C/imunologia , Lipopolissacarídeos/farmacologia , MAP Quinase Quinase Quinase 5/imunologia , Ligação Proteica , RNA Interferente Pequeno/genética , Receptores de Superfície Celular/imunologia , Transfecção
9.
Cancer ; 119(22): 4003-11, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23963810

RESUMO

BACKGROUND: A previous comparative tissue proteomics study by the authors of the current study led to the identification of caldesmon (CaD) as one of the proteins associated with cervical metastasis of oral cavity squamous cell carcinoma (OSCC). In the current investigation, the authors focused on the potential functions of CaD in patients with OSCC. METHODS: CaD expression was examined in tissue samples from 155 patients using immunohistochemical analysis. The expression of CaD variants was determined by Western blot analysis and reverse transcriptase-polymerase chain reaction. In addition, the specific effects of CaD gene overexpression and silence were determined in OSCC cell lines. RESULTS: CaD expression was found to be significantly higher in tumor cells from metastatic lymph nodes compared with primary tumor cells, and was nearly absent in normal oral epithelia. Higher CaD expression was found to be correlated with positive N classification, poor differentiation, perineural invasion, and tumor depth (P = .001, P = .029, P = .001, and P = .031, respectively). In survival analyses, OSCC patients with higher CaD expression were found to have poorer prognosis with regard to disease-specific survival and disease-free survival (P = .003 and P = .014, respectively). Multivariate analyses further indicated that higher CaD expression was an independent predictor of disease-specific survival (P = .043). Serum CaD levels were found to be significantly higher in patients with OSCC, but this finding was not associated with clinicopathological manifestations. Data obtained from in vitro suppression, rescue, and overexpression of CaD in OEC-M1 cells indicated that CaD promotes migration and invasive processes in OSCC cells. CONCLUSIONS: The findings of the current study collectively suggest that the low-molecular-weight CaD expression in OSCC tumors is associated with tumor metastasis and patient survival.


Assuntos
Proteínas de Ligação a Calmodulina/biossíntese , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias Bucais/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Ligação a Calmodulina/genética , Proteínas de Ligação a Calmodulina/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Técnicas de Cultura de Células , Movimento Celular/fisiologia , Intervalo Livre de Doença , Feminino , Inativação Gênica , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Adulto Jovem
10.
BMC Biochem ; 14: 18, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23870088

RESUMO

BACKGROUND: Lamins A and C, two major structural components of the nuclear lamina that determine nuclear shape and size, are phosphoproteins. Phosphorylation of lamin A/C is cell cycle-dependent and is involved in regulating the assembly-disassembly of lamin filaments during mitosis. We previously reported that P-STM, a phosphoepitope-specific antibody raised against the autophosphorylation site of p21-activated kinase 2, recognizes a number of phosphoproteins, including lamins A and C, in mitotic HeLa cells. RESULTS: Here, using recombinant proteins and synthetic phosphopeptides containing potential lamin A/C phosphorylation sites in conjunction with in vitro phosphorylation assays, we determined the lamin A/C phosphoepitope(s) recognized by P-STM. We found that phosphorylation of Thr-19 is required for generating the P-STM phosphoepitope in lamin A/C and showed that it could be created in vitro by p34cdc2/cyclin B kinase (CDK1)-catalyzed phosphorylation of lamin A/C immunoprecipitated from unsynchronized HeLa S3 cells. To further explore changes in lamin A/C phosphorylation in living cells, we precisely quantified the phosphorylation levels of Thr-19 and other sites in lamin A/C isolated from HeLa S3 cells at interphase and mitosis using the SILAC method and liquid chromatography-tandem mass spectrometry. The results showed that the levels of phosphorylated Thr-19, Ser-22 and Ser-392 in both lamins A and C, and Ser-636 in lamin A only, increased -2- to 6-fold in mitotic HeLa S3 cells. CONCLUSIONS: Collectively, our results demonstrate that P-STM is a useful tool for detecting Thr-19-phosphorylated lamin A/C in cells and reveal quantitative changes in the phosphorylation status of major lamin A/C phosphorylation sites during mitosis.


Assuntos
Anticorpos/imunologia , Lamina Tipo A/metabolismo , Fosfopeptídeos/imunologia , Sequência de Aminoácidos , Proteína Quinase CDC2/metabolismo , Isótopos de Carbono/química , Cromatografia Líquida de Alta Pressão , Células HeLa , Humanos , Imunoprecipitação , Marcação por Isótopo , Lamina Tipo A/química , Mitose , Dados de Sequência Molecular , Fosfopeptídeos/análise , Fosfopeptídeos/isolamento & purificação , Fosforilação , Espectrometria de Massas em Tandem
11.
Heliyon ; 9(5): e16408, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37251870

RESUMO

Background: Chromosome analysis is laborious and time-consuming. Automated methods can significantly increase the efficiency of chromosome analysis. For the automated analysis of chromosome images, single and clustered chromosomes must be identified. Herein, we propose a feature-based method for distinguishing between single chromosomes and clustered chromosome. Method: The proposed method comprises three main steps. In the first step, chromosome objects are segmented from metaphase chromosome images in advance. In the second step, seven features are extracted from each segmented object, i.e., the normalized area, area/boundary ratio, side branch index, exhaustive thresholding index, normalized minimum width, minimum concave angle, and maximum boundary shift. Finally, the segmented objects are classified as a single chromosome or chromosome cluster using a combination of the seven features. Results: In total, 43,391 segmented objects, including 39,892 single chromosomes and 3,499 chromosome clusters, are used to evaluate the proposed method. The results show that the proposed method achieves an accuracy of 98.92% by combining the seven features using support vector machine. Conclusions: The proposed method is highly effective in distinguishing between single and clustered chromosomes and can be used as a preprocessing procedure for automated chromosome image analysis.

12.
Cells ; 12(7)2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-37048130

RESUMO

Constitutive activation of the phosphoinositide-3-kinase (PI3K)/Akt signaling pathway is crucial for tumor growth and progression. As such, this pathway has been an enticing target for drug discovery. Although HS-173 is a potent PI3K inhibitor that halts cancer cell proliferation via G2/M cell cycle arrest, the resistance mechanisms to HS-173 have not been investigated. In this study, we investigated the susceptibility of HS-173 to efflux mediated by the multidrug efflux transporters ABCB1 and ABCG2, which are two of the most well-known ATP-binding cassette (ABC) transporters associated with the development of cancer multidrug resistance (MDR). We found that the overexpression of ABCB1 or ABCG2 significantly reduced the efficacy of HS-173 in human cancer cells. Our data show that the intracellular accumulation of HS-173 was substantially reduced by ABCB1 and ABCG2, affecting G2/M arrest and apoptosis induced by HS-173. More importantly, the efficacy of HS-173 in multidrug-resistant cancer cells could be recovered by inhibiting the drug-efflux function of ABCB1 and ABCG2. Taken together, our study has demonstrated that HS-173 is a substrate for both ABCB1 and ABCG2, resulting in decreased intracellular concentration of this drug, which may have implications for its clinical use.


Assuntos
Resistência a Múltiplos Medicamentos , Neoplasias , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Apoptose , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral , Pontos de Checagem da Fase G2 do Ciclo Celular , Transportadores de Cassetes de Ligação de ATP/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Neoplasias/tratamento farmacológico , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Neoplasias/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP
13.
J Microbiol Immunol Infect ; 55(1): 86-94, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33678555

RESUMO

BACKGROUND: Imipenem-relebactam is a new ß-lactam and ß-lactamase inhibitor combination to treat carbapenem-resistant gram-negative bacteria infections. However, difference in carbapenem resistant mechanisms existed with geographic variations. OBJECTIVE: To evaluate the susceptibility of imipenem-relebactam to 660 carbapenem-nonsusceptible Enterobacteriaceae isolates in Taiwan and to identify the in vivo efficacy with a Caenorhabditis elegans model. METHODS: 188 carbapenem-nonsusceptible Escherichia coli isolates and 472 carbapenem-nonsusceptible Klebsiella pneumoniae isolates were collected from a national surveillance study in Taiwan. The antimicrobial susceptibility profiles and carbapenemase distributions were determined. An agar dilution method was performed to evaluate the in vitro activities of imipenem monotherapy and imipenem-relebactam combination. Contributions of metallo-carbapenemase to imipenem-relebactam susceptibility was investigated via EDTA treatment. A C. elegans model was used to evaluate the in vivo efficacy of imipenem-relebactam combination. RESULTS: 87.8% and 82.2% susceptibility to imipenem-relebactam was observed for 188 carbapenem-nonsusceptible E. coli and 472 carbapenem-nonsusceptible K. pneumoniae, respectively. However, poor activities of imipenem-relebactam was observed against 23 metallo-carbapenemase producers tested in this study. In the in vivo C. elegans model, imipenem-relebactam significantly rescued nematodes from the infection of a blaKPC-producing K. pneumoniae isolate. CONCLUSION: Our study supports that imipenem-relebactam is a potential therapy against carbapenem-nonsusceptible Enterobacteriaceae, and to our knowledge, this is the first report of evaluation for imipenem-relebactam efficacy against carbapenem-nonsusceptible Enterobacteriaceae in Taiwan.


Assuntos
Antibacterianos , Compostos Azabicíclicos , Enterobacteriaceae , Imipenem , Animais , Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Proteínas de Bactérias , Caenorhabditis elegans , Carbapenêmicos/farmacologia , Combinação de Medicamentos , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Escherichia coli , Humanos , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Taiwan , beta-Lactamases
14.
Anal Chim Acta ; 1189: 339218, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34815039

RESUMO

Metabolomics, which serves as a readout of biological processes and diseases monitoring, is an informative research area for disease biomarker discovery and systems biology studies. In particular, reversed-phase liquid chromatography-mass spectrometry (RPLC-MS) has become a powerful and popular tool for metabolomics analysis, enabling the detection of most metabolites. Very polar and ionic metabolites, however, are less easily detected because of their poor retention in RP columns. Dansylation of metabolites simplifies the sub-metabolome analysis by reducing its complexity and increasing both hydrophobicity and ionization ability. However, the various metabolite concentrations in clinical samples have a wide dynamic range with highly individual variation in total metabolite amount, such as in saliva. The bicarbonate buffer typically used in dansylation labeling reactions induces solvent stratification, resulting in poor reproducibility, selective sample loss and an increase in false-determined metabolite peaks. In this study, we optimized the dansylation protocol for samples with wide concentration range of metabolites, utilizing diisopropylethylamine (DIPEA) or tri-ethylamine (TEA) in place of bicarbonate buffer, and presented the results of a systemic investigation of the influences of individual processes involved on the overall performance of the protocol. In addition to achieving high reproducibility, substitution of DIPEA or TEA buffer resulted in similar labeling efficiency of most metabolites and more efficient labeling of some metabolites with a higher pKa. With this improvement, compounds that are only present in samples in trace amounts can be detected, and more comprehensive metabolomics profiles can be acquired for biomarker discovery or pathway analysis, making it possible to analyze clinical samples with limited amounts of metabolites.


Assuntos
Aminas , Fenol , Compostos de Dansil , Marcação por Isótopo , Fenóis , Reprodutibilidade dos Testes , Solventes
15.
Biomed Pharmacother ; 154: 113663, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36081287

RESUMO

The development of multidrug resistance (MDR) is one of the major challenges in the treatment of cancer which is caused by the overexpression of the ATP-binding cassette (ABC) transporters ABCB1 (P-glycoprotein) and/or ABCG2 (BCRP/MXR/ABCP) in cancer cells. These transporters are capable of reducing the efficacy of cytotoxic drugs by actively effluxing them out of cancer cells. Since there is currently no approved treatment for patients with multidrug-resistant tumors, the drug repurposing approach provides an alternative route to identify agents to reverse MDR mediated by ABCB1 and/or ABCG2 in multidrug-resistant cancer cells. WDR5-0103 is a histone H3 lysine 4 (H3K4) methyltransferase inhibitor that disrupts the interaction between the WD repeat-containing protein 5 (WDR5) and mixed-lineage leukemia (MLL) protein. In this study, the effect of WDR5-0103 on MDR mediated by ABCB1 and ABCG2 was determined. We found that in a concentration-dependent manner, WDR5-0103 could sensitize ABCB1- and ABCG2-overexpressing multidrug-resistant cancer cells to conventional cytotoxic drugs. Our results showed that WDR5-0103 reverses MDR and improves drug-induced apoptosis in multidrug-resistant cancer cells by inhibiting the drug-efflux function of ABCB1 and ABCG2, without altering the protein expression of ABCB1 or ABCG2. The potential sites of interactions of WDR5-0103 with the drug-binding pockets of ABCB1 and ABCG2 were predicted by molecular docking. In conclusion, the MDR reversal activity of WDR5-0103 demonstrated here indicates that it could be used in combination therapy to provide benefits to a subset of patients with tumor expressing high levels of ABCB1 or ABCG2.


Assuntos
Antineoplásicos , Neoplasias , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Simulação de Acoplamento Molecular , Proteínas de Neoplasias/metabolismo , Repetições WD40
16.
Front Microbiol ; 13: 896588, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406412

RESUMO

Hepatitis C virus (HCV) NS3/4A protease is an attractive target for direct-acting antiviral agents. Real-time tracking of the NS3/4A protease distribution and activity is useful for clinical diagnosis and disease management. However, no approach has been developed that can systemically detect NS3/4A protease activity or distribution. We designed a protease-activatable retention probe for tracking HCV NS3/4A protease activity via positron emission topography (PET) imaging. A cell-penetrating probe was designed that consisted of a cell-penetrating Tat peptide, HCV NS3/4A protease substrate, and a hydrophilic domain. The probe was labeled by fluorescein isothiocyanate (FITC) and 124I in the hydrophilic domain to form a TAT-ΔNS3/4A-124I-FITC probe. Upon cleavage at NS3/4A substrate, the non-penetrating hydrophilic domain is released and accumulated in the cytoplasm allowing PET or optical imaging. The TAT-ΔNS3/4A-FITC probe selectively accumulated in NS3/4A-expressing HCC36 (NS3/4A-HCC36) cells/tumors and HCV-infected HCC36 cells. PET imaging showed that the TAT-ΔNS3/4A-124I-FITC probe selectively accumulated in the NS3/4A-HCC36 xenograft tumors and liver-implanted NS3/4A-HCC36 tumors, but not in the control HCC36 tumors. The TAT-ΔNS3/4A-124I-FITC probe can be used to represent NS3/4 protease activity and distribution via a clinical PET imaging system allowing. This strategy may be extended to detect any cellular protease activity for optimization the protease-based therapies.

17.
J Clin Nurs ; 20(7-8): 988-99, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21385249

RESUMO

AIMS: To determine the effect of music therapy and verbal relaxation on state anxiety and anxiety-induced physiological manifestations among patients with cancer before and after chemotherapy. BACKGROUND: Cancer and its treatment provoke a series of changes in the emotional sphere of the patient's anxiety. Music therapy and verbal relaxation had reported the anxiety reduction effect on patients with cancer receiving chemotherapy. Few studies have been undertaken comparing music therapy and verbal relaxation in differentiating high-normal state anxiety subsample. DESIGN: A randomised controlled trial and permuted block design were used. Outpatient chemotherapy clinic operated by a University medical centre in southern Taiwan. METHODS: Ninety-eight patients were randomised into three groups: the music therapy group received one-hour single music session; the verbal relaxation group received 30 minutes of guided relaxation; the control group received usual care. Spielberger State-Trait Anxiety Instrument, Emotional Visual Analog Scale, three biobehavioural indicators: skin temperature, heart rate and consciousness level were measured during and after chemotherapy. RESULT: Music therapy had a greater positive effect on postchemotherapy anxiety than verbal relaxation and control groups and a significantly increase in skin temperature. Patients with high state anxiety receiving music therapy had a greater drop in postchemotherapy anxiety than did the normal state anxiety subsample. CONCLUSIONS: Both music and verbal relaxation therapy are effective in reducing chemotherapy-induced anxiety. Thirty minutes of intervention initiates anxiety reduction. Patients with high state anxiety receiving chemotherapy obtain the most benefit from music or verbal relaxation. RELEVANCE TO CLINICAL PRACTICE: Prior to chemotherapy, patients with high state anxiety must be sorted from all patients as they are more responsive to interventions. Oncology nurses can offer music and verbal relaxation as adjuvant interventions to reduce chemotherapy-induced anxiety and enhance the quality of care.


Assuntos
Antineoplásicos/efeitos adversos , Ansiedade/terapia , Musicoterapia , Ansiedade/induzido quimicamente , Humanos , Taiwan
18.
Pharmaceuticals (Basel) ; 14(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34451891

RESUMO

Colistin- and carbapenem-resistant Enterobacteriaceae cases are increasing at alarming rates worldwide. Drug repurposing is receiving greater attention as an alternative approach in light of economic and technical barriers in antibiotics research. The immunomodulation agent ammonium trichloro(dioxoethylene-O,O'-)tellurate (AS101) was repurposed as an antimicrobial agent against colistin- and carbapenem-resistant Klebsiella pneumoniae (CRKP). 134 CRKP isolates were collected between 2012 and 2015 in Taiwan. The in vitro antibacterial activities of AS101 was observed through broth microdilution, time-kill assay, and electron microscopy. Pharmaceutical manipulation and RNA microarray were applied to investigate these antimicrobial mechanisms. Caenorhabditis elegans, a nematode animal model, and the Institute for Cancer Research (ICR) mouse model was employed for the evaluation of in vivo efficacy. The in vitro antibacterial results were found for AS101 against colistin- and CRKP isolates, with minimum inhibitory concentration (MIC) values ranging from <0.5 to 32 µg/mL. ROS-mediated antibacterial activity eliminated 99.9% of bacteria within 2-4 h. AS101 also extended the median survival time in a C. elegans animal model infected with a colistin-resistant CRKP isolate and rescued lethally infected animals in a separate mouse model of mono-bacterial sepsis by eliminating bacterial organ loads. These findings support the use of AS101 as an antimicrobial agent for addressing the colistin and carbapenem resistance crisis.

19.
J Chin Med Assoc ; 84(7): 682-689, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074933

RESUMO

BACKGROUND: Currently, as the coronavirus disease (COVID-19) has become a pandemic, rapidly obtaining accurate information of patient symptoms and their progression is crucial and vital. Although the early studies in China have illustrated that the representative symptoms of COVID-19 include (dry) cough, fever, headache, fatigue, gastrointestinal discomfort, dyspnea, and muscle pain, there is increasing evidence to suggest that olfactory and taste disorder are related to the COVID-19 pandemic. Therefore, we conduct this study to review the present literature about the correlation between anosmia or dysgeusia and COVID-19. METHODS: A comprehensive literature search in 2020 of the electronic journal databases, mainly PubMed or Web of Science, was performed using the keywords COVID-19 or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with hyposmia, anosmia, dysgeusia, olfactory disorder, or olfactory dysfunction. The country, study period, case number, inpatient or outpatient medical visit, evaluation method (subjective complaints of dysfunction or objective evaluation), and occurrence rate of olfactory or gustatory function were reviewed. RESULTS: Many studies reported that the recoverable olfactory or gustatory dysfunction may play an important role as the early clinical symptom of COVID-19. It is associated with better prognosis, although further investigation and validation should be carried out. CONCLUSION: Studies have shown that smell and taste disturbances may represent an early symptom of COVID-19 and healthcare professionals must be very vigilant when managing patients with these symptoms. In the pandemic era, this implies testing for COVID-19 by healthcare workers with full personal protective equipment.


Assuntos
COVID-19/complicações , Transtornos do Olfato/etiologia , SARS-CoV-2 , Distúrbios do Paladar/etiologia , Enzima de Conversão de Angiotensina 2/fisiologia , COVID-19/diagnóstico , Teste para COVID-19 , Humanos
20.
Int J Nanomedicine ; 16: 7813-7830, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34880610

RESUMO

INTRODUCTION: Osteoporosis is a result of an imbalance in bone remodeling. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have been considered as a potentially promising treatment for osteoporosis. However, the therapeutic effect, genetic alterations, and in vivo behavior of exogenous EVs for osteoporosis in mice models remain poorly understood. METHODS: A multiplexed molecular imaging strategy was constructed by micro-positron emission tomography (µPET)/computed tomography (CT), µCT, and optical imaging modality which reflected the osteoblastic activity, microstructure, and in vivo behavior of EVs, respectively. RNA sequencing was used to analyze the cargo of EVs, and the bone tissues of ovariectomized (OVX) mice post EV treatment. RESULTS: The result of [18F]NaF µPET showed an increase in osteoblastic activity in the distal femur of EV-treated mice, and the bone structural parameters derived from µCT were also improved. In terms of in vivo behavior of exogenous EVs, fluorescent dye-labeled EVs could target the distal femur of mice, whereas the uptakes of bone tissues were not significantly different between OVX mice and healthy mice. RNA sequencing demonstrated upregulation of ECM-related genes, which might associate with the PI3K/AKT signaling pathway, in line with the results of microRNA analysis showing that mir-21, mir-29, mir-221, and let-7a were enriched in Wharton's jelly-MSC-EVs and correlated to the BMP and PI3K/AKT signaling pathways. CONCLUSION: The therapeutic effect of exogenous WJ-MSC-EVs in the treatment of osteoporosis was successfully assessed by a multiplexed molecular imaging strategy. The RNA sequencing demonstrated the possible molecular targets in the regulation of bone remodeling. The results highlight the novelty of diagnostic and therapeutic strategies of EV-based treatment for osteoporosis.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , MicroRNAs , Osteoporose , Geleia de Wharton , Animais , Camundongos , Imagem Molecular , Osteoporose/diagnóstico por imagem , Osteoporose/terapia , Fosfatidilinositol 3-Quinases , Análise de Sequência de RNA
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