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1.
Adv Sci (Weinh) ; 10(14): e2206812, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36949364

RESUMO

A critical barrier to effective cancer therapy is the improvement of drug selectivity, toxicity, and reduced recurrence of tumors expanded from tumor-initiating stem-like cells (TICs). The aim is to identify circulating tumor cell (CTC)-biomarkers and to identify an effective combination of TIC-specific, repurposed federal drug administration (FDA)-approved drugs. Three different types of high-throughput screens targeting the TIC population are employed: these include a CD133 (+) cell viability screen, a NANOG expression screen, and a drug combination screen. When combined in a refined secondary screening approach that targets Nanog expression with the same FDA-approved drug library, histone deacetylase (HDAC) inhibitor(s) combined with all-trans retinoic acid (ATRA) demonstrate the highest efficacy for inhibition of TIC growth in vitro and in vivo. Addition of immune checkpoint inhibitor further decreases recurrence and extends PDX mouse survival. RNA-seq analysis of TICs reveals that combined drug treatment reduces many Toll-like receptors (TLR) and stemness genes through repression of the lncRNA MIR22HG. This downregulation induces PTEN and TET2, leading to loss of the self-renewal property of TICs. Thus, CTC biomarker analysis would predict the prognosis and therapy response to this drug combination. In general, biomarker-guided stratification of HCC patients and TIC-targeted therapy should eradicate TICs to extend HCC patient survival.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células Neoplásicas Circulantes , Camundongos , Animais , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Linhagem Celular Tumoral , Tretinoína/uso terapêutico
2.
iScience ; 26(3): 106254, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36949755

RESUMO

Chemoresistance and plasticity of tumor-initiating stem-like cells (TICs) promote tumor recurrence and metastasis. The gut-originating endotoxin-TLR4-NANOG oncogenic axis is responsible for the genesis of TICs. This study investigated mechanisms as to how TICs arise through transcriptional, epigenetic, and post-transcriptional activation of oncogenic TLR4 pathways. Here, we expressed constitutively active TLR4 (caTLR4) in mice carrying pLAP-tTA or pAlb-tTA, under a tetracycline withdrawal-inducible system. Liver progenitor cell induction accelerated liver tumor development in caTLR4-expressing mice. Lentiviral shRNA library screening identified histone H3K4 methylase SETD7 as central to activation of TLR4. SETD7 combined with hypoxia induced TLR4 through HIF2 and NOTCH. LIN28 post-transcriptionally stabilized TLR4 mRNA via de-repression of let-7 microRNA. These results supported a LIN28-TLR4 pathway for the development of HCCs in a hypoxic microenvironment. These findings not only advance our understanding of molecular mechanisms responsible for TIC generation in HCC, but also represent new therapeutic targets for the treatment of HCC.

3.
Mol Cancer Res ; 21(2): 155-169, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36287175

RESUMO

Synergism between obesity and virus infection promotes the development of B-cell lymphoma. In this study, we tested whether obesity-associated endotoxin release induced activation-induced cytidine deaminase (AID). TLR4 activation in turn caused c-JUN-dependent and STAT3-dependent translocations of MYC loci to suppress transactivation of CD95/FAS. We used viral nucleocapside Core transgenic (Tg) mice fed alcohol Western diet to determine whether oncogenesis arising from obesity and chronic virus infection occurred through TLR4-c-JUN-STAT3 pathways. Our results showed B cell-specific, c-Jun and/or Stat3 disruption reduced the incidence of splenomegaly in these mice. AID-dependent t(8;14) translocation was observed between the Ig promoter and MYC loci. Comparison with human B cells showed MYC-immunoglobulin (Ig) translocations after virus infection with lipopolysaccharide stimulation. Accordingly, human patients with lymphoma with virus infections and obesity showed a 40% incidence of MYC-Ig translocations. Thus, obesity and virus infection promote AID-mediated translocation between the Ig promoter and MYC through the TLR4-c-JUN axis, resulting in lymphoproliferation. Taken together, preventative treatment targeting either c-JUN and/or STAT3 may be effective strategies to prevent tumor development. IMPLICATIONS: Obesity increases gut-derived endotoxin which induces Toll-like receptor-mediated MYC-Ig translocation via c-JUN-STAT3, leading to lymphoproliferation.


Assuntos
Endotoxinas , Receptor 4 Toll-Like , Humanos , Camundongos , Animais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Endotoxinas/metabolismo , Imunoglobulinas/metabolismo , Camundongos Transgênicos , Linfócitos B , Translocação Genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
4.
ACS Omega ; 7(50): 46486-46493, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36570316

RESUMO

ß-lactam-resistant Vibrio strains are a significant clinical problem, and ß-lactamase inhibitors are generally coadministered with ß-lactam drugs to control drug-resistant bacteria. Seaweed is a rich source of natural bioactive compounds; however, their potential as ß-lactamase inhibitors against bacterial pathogens remains unknown. Herein, we evaluated the potential ß-lactamase inhibitory effect of the ethanolic extracts of the red seaweed Gracilaria sp. (GE) against four Vibrio strains. The minimum inhibitory concentration, half-maximal inhibitory concentration, checkerboard assay results, and time-kill study results indicate that GE has limited antibacterial activity but can potentiate the activity of the ß-lactam antibiotic carbenicillin against Vibrio parahemolyticus and V. cholerae. We overexpressed and purified recombinant metallo-ß-lactamase, VarG, from V. cholerae for in vitro studies and observed that adding GE reduced the carbenicillin and nitrocefin degradation by VarG by 20% and 60%, respectively. Angiotensin I-converting enzyme inhibition studies demonstrated that GE did not inhibit VarG via metal chelation. Toxicity assays indicated that GE exhibited mild toxicity against human cells. Through gas chromatography and mass spectrometry, we showed that GE comprises alkaloids, phenolic compounds, terpenoids, terpenes, and halogenated aromatic compounds. This study revealed that extracts of the red seaweed Gracillaria sp. can potentially inhibit ß-lactamase activity.

5.
Int J Med Sci ; 19(6): 1013-1022, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813301

RESUMO

Single nucleotide polymorphisms (SNPs) of tissue inhibitor of metalloproteinases-3 (TIMP-3) have been revealed to be related to various cancers. To date, no study explores the relationships between TIMP-3 polymorphisms and uterine cervical cancer. The purposes of this research were to investigate the associations among genetic variants of TIMP-3 and development and clinicopathological factors of uterine cervical cancer, and patient 5 years survival in Taiwanese women. The study included 123 patients with invasive cancer and 97 with precancerous lesions of uterine cervix, and 300 control women. TIMP-3 polymorphisms rs9619311, rs9862 and rs11547635 were checked and their genotypic distributions were determined by real-time polymerase chain reaction. It showed that women with genotypes CT/TT in rs9862 were found to display a higher risk of developing cervical cancer with moderate and poor cell differentiation. Moreover, it revealed that cervical cancer patients carrying genotypes CC in rs9619311 exhibited a poorer 5 years survival, as compared to those with TT/TC in Taiwanese women, using univariate analysis. In addition, pelvic lymph node metastasis was determined to independently predict 5 years survival in cervical cancer patients using multivariate analysis. Conclusively, TIMP-3 SNPs polymorphisms rs9619311 are related to cervical patient survival in Taiwanese women.


Assuntos
Neoplasias do Colo do Útero , Feminino , Predisposição Genética para Doença/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , Taiwan/epidemiologia , Inibidor Tecidual de Metaloproteinase-3/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia
6.
iScience ; 25(6): 104325, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35601917

RESUMO

Metabolic syndrome is associated with obesity, insulin resistance, and the risk of cancer. We tested whether oncogenic transcription factor c-JUN metabolically reprogrammed cells to induce obesity and cancer by reduction of glucose uptake, with promotion of the stemness phenotype leading to malignant transformation. Liquid alcohol, high-cholesterol, fat diet (HCFD), and isocaloric dextrin were fed to wild-type or experimental mice for 12 months to promote hepatocellular carcinoma (HCC). We demonstrated 40% of mice developed liver tumors after chronic HCFD feeding. Disruption of liver-specific c-Jun reduced tumor incidence 4-fold and improved insulin sensitivity. Overexpression of c-JUN downregulated RICTOR transcription, leading to inhibition of the mTORC2/AKT and glycolysis pathways. c-JUN inhibited GLUT1, 2, and 3 transactivation to suppress glucose uptake. Silencing of RICTOR or c-JUN overexpression promoted self-renewal ability. Taken together, c-JUN inhibited mTORC2 via RICTOR downregulation and inhibited glucose uptake via downregulation of glucose intake, leading to self-renewal and obesity.

7.
Front Cell Dev Biol ; 10: 890419, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35602596

RESUMO

TEAD4 (TEA Domain Transcription Factor 4) is well recognized as the DNA-anchor protein of YAP transcription complex, which is modulated by Hippo, a highly conserved pathway in Metazoa that controls organ size through regulating cell proliferation and apoptosis. To acquire full transcriptional activity, TEAD4 requires co-activator, YAP (Yes-associated protein) or its homolog TAZ (transcriptional coactivator with PDZ-binding motif) the signaling hub that relays the extracellular stimuli to the transcription of target genes. Growing evidence suggests that TEAD4 also exerts its function in a YAP-independent manner through other signal pathways. Although TEAD4 plays an essential role in determining that differentiation fate of the blastocyst, it also promotes tumorigenesis by enhancing metastasis, cancer stemness, and drug resistance. Upregulation of TEAD4 has been reported in several cancers, including colon cancer, gastric cancer, breast cancer, and prostate cancer and serves as a valuable prognostic marker. Recent studies show that TEAD4, but not other members of the TEAD family, engages in regulating mitochondrial dynamics and cell metabolism by modulating the expression of mitochondrial- and nuclear-encoded electron transport chain genes. TEAD4's functions including oncogenic activities are tightly controlled by its subcellular localization. As a predominantly nuclear protein, its cytoplasmic translocation is triggered by several signals, such as osmotic stress, cell confluency, and arginine availability. Intriguingly, TEAD4 is also localized in mitochondria, although the translocation mechanism remains unclear. In this report, we describe the current understanding of TEAD4 as an oncogene, epigenetic regulator and mitochondrial modulator. The contributing mechanisms will be discussed.

8.
J Chin Med Assoc ; 85(2): 259-262, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34974508

RESUMO

Total implantable venous access port (TIVAP) by cephalic vein cutdown (CVCD) is one of the first procedures surgery residents can be performed independently under supervision. There is currently a lack of affordable simulators for teaching and assessing TIVAP competency to improve patient safety. A panel of 10 experts divided the TIVAP by CVCD procedure into 9 steps. A homemade, low-cost ($3 USD) simulator was then designed for practicing standardized procedural steps in the context of a simulation-based mastery learning course. Residents were given a simulator for at-home practice and completed a survey evaluating the simulator and their learning experience. Twenty-eight first-year surgery residents participated in the course and completed the survey. They were highly satisfied with the simulator (mean score = 8.7 of 10) and generally agreed with its anatomical appearance and functional fidelity. They also appreciated the educational value of using this simulator to learn and practice basic techniques and procedural steps. Our novel, homemade simulator of CVCD TIVAP implantation is a cost-effective way of achieving procedural competence of a basic operation for inexperienced surgery residents. We envision the same principle can be applied to other procedures to enhance resident education.


Assuntos
Cateterismo Venoso Central/normas , Competência Clínica , Treinamento por Simulação , Dispositivos de Acesso Vascular , Venostomia/educação , Humanos , Inquéritos e Questionários
9.
Int J Mol Sci ; 22(24)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34948229

RESUMO

Increasing evidence suggests that tumor development requires not only oncogene/tumor suppressor mutations to drive the growth, survival, and metastasis but also metabolic adaptations to meet the increasing energy demand for rapid cellular expansion and to cope with the often nutritional and oxygen-deprived microenvironment. One well-recognized strategy is to shift the metabolic flow from oxidative phosphorylation (OXPHOS) or respiration in mitochondria to glycolysis or fermentation in cytosol, known as Warburg effects. However, not all cancer cells follow this paradigm. In the development of prostate cancer, OXPHOS actually increases as compared to normal prostate tissue. This is because normal prostate epithelial cells divert citrate in mitochondria for the TCA cycle to the cytosol for secretion into seminal fluid. The sustained level of OXPHOS in primary tumors persists in progression to an advanced stage. As such, targeting OXPHOS and mitochondrial activities in general present therapeutic opportunities. In this review, we summarize the recent findings of the key regulators of the OXPHOS pathway in prostate cancer, ranging from transcriptional regulation, metabolic regulation to genetic regulation. Moreover, we provided a comprehensive update of the current status of OXPHOS inhibitors for prostate cancer therapy. A challenge of developing OXPHOS inhibitors is to selectively target cancer mitochondria and spare normal counterparts, which is also discussed.


Assuntos
Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Mitocôndrias , Fosforilação Oxidativa/efeitos dos fármacos , Neoplasias da Próstata , Transdução de Sinais , Ciclo do Ácido Cítrico/efeitos dos fármacos , Ciclo do Ácido Cítrico/genética , Humanos , Masculino , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
10.
PLoS Pathog ; 17(8): e1009724, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34352041

RESUMO

Hemagglutinin (HA) is the immunodominant protein of the influenza virus. We previously showed that mice injected with a monoglycosylated influenza A HA (HAmg) produced cross-strain-reactive antibodies and were better protected than mice injected with a fully glycosylated HA (HAfg) during lethal dose challenge. We employed a single B-cell screening platform to isolate the cross-protective monoclonal antibody (mAb) 651 from mice immunized with the HAmg of A/Brisbane/59/2007 (H1N1) influenza virus (Bris/07). The mAb 651 recognized the head domain of a broad spectrum of HAs from groups 1 and 2 influenza A viruses and offered prophylactic and therapeutic efficacy against A/California/07/2009 (H1N1) (Cal/09) and Bris/07 infections in mice. The antibody did not possess neutralizing activity; however, antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis mediated by natural killer cells and alveolar macrophages were important in the protective efficacy of mAb 651. Together, this study highlighted the significance of effector functions for non-neutralizing antibodies to exhibit protection against influenza virus infection.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/farmacologia , Citotoxicidade Celular Dependente de Anticorpos , Vírus da Influenza A/imunologia , Células Matadoras Naturais/imunologia , Macrófagos Alveolares/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/farmacologia , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/virologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/virologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia
11.
Cancers (Basel) ; 13(14)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34298755

RESUMO

Arginine is an amino acid critically involved in multiple cellular processes including the syntheses of nitric oxide and polyamines, and is a direct activator of mTOR, a nutrient-sensing kinase strongly implicated in carcinogenesis. Yet, it is also considered as a non- or semi-essential amino acid, due to normal cells' intrinsic ability to synthesize arginine from citrulline and aspartate via ASS1 (argininosuccinate synthase 1) and ASL (argininosuccinate lyase). As such, arginine can be used as a dietary supplement and its depletion as a therapeutic strategy. Strikingly, in over 70% of tumors, ASS1 transcription is suppressed, rendering the cells addicted to external arginine, forming the basis of arginine-deprivation therapy. In this review, we will discuss arginine as a signaling metabolite, arginine's role in cancer metabolism, arginine as an epigenetic regulator, arginine as an immunomodulator, and arginine as a therapeutic target. We will also provide a comprehensive summary of ADI (arginine deiminase)-based arginine-deprivation preclinical studies and an update of clinical trials for ADI and arginase. The different cell killing mechanisms associated with various cancer types will also be described.

12.
Theranostics ; 11(15): 7527-7545, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34158865

RESUMO

Rationale: One of the most common metabolic defects in cancers is the deficiency in arginine synthesis, which has been exploited therapeutically. Yet, challenges remain, and the mechanisms of arginine-starvation induced killing are largely unclear. Here, we sought to demonstrate the underlying mechanisms by which arginine starvation-induced cell death and to develop a dietary arginine-restriction xenograft model to study the in vivo effects. Methods: Multiple castration-resistant prostate cancer cell lines were treated with arginine starvation followed by comprehensive analysis of microarray, RNA-seq and ChIP-seq were to identify the molecular and epigenetic pathways affected by arginine starvation. Metabolomics and Seahorse Flux analyses were used to determine the metabolic profiles. A dietary arginine-restriction xenograft mouse model was developed to assess the effects of arginine starvation on tumor growth and inflammatory responses. Results: We showed that arginine starvation coordinately and epigenetically suppressed gene expressions, including those involved in oxidative phosphorylation and DNA repair, resulting in DNA damage, chromatin-leakage and cGAS-STING activation, accompanied by the upregulation of type I interferon response. We further demonstrated that arginine starvation-caused depletion of α-ketoglutarate and inactivation of histone demethylases are the underlying causes of epigenetic silencing. Significantly, our dietary arginine-restriction model showed that arginine starvation suppressed prostate cancer growth in vivo, with evidence of enhanced interferon responses and recruitment of immune cells. Conclusions: Arginine-starvation induces tumor cell killing by metabolite depletion and epigenetic silencing of metabolic genes, leading to DNA damage and chromatin leakage. The resulting cGAS-STING activation may further enhance these killing effects.


Assuntos
Arginina/deficiência , Cromatina/metabolismo , Reparo do DNA , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Nucleotidiltransferases/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo , Cromatina/genética , Cromatina/patologia , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Nucleotidiltransferases/genética , Células PC-3 , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia
13.
Nat Commun ; 12(1): 2398, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893278

RESUMO

Arginine plays diverse roles in cellular physiology. As a semi-essential amino acid, arginine deprivation has been used to target cancers with arginine synthesis deficiency. Arginine-deprived cancer cells exhibit mitochondrial dysfunction, transcriptional reprogramming and eventual cell death. In this study, we show in prostate cancer cells that arginine acts as an epigenetic regulator to modulate histone acetylation, leading to global upregulation of nuclear-encoded oxidative phosphorylation (OXPHOS) genes. TEAD4 is retained in the nucleus by arginine, enhancing its recruitment to the promoter/enhancer regions of OXPHOS genes and mediating coordinated upregulation in a YAP1-independent but mTOR-dependent manner. Arginine also activates the expression of lysine acetyl-transferases and increases overall levels of acetylated histones and acetyl-CoA, facilitating TEAD4 recruitment. Silencing of TEAD4 suppresses OXPHOS functions and prostate cancer cell growth in vitro and in vivo. Given the strong correlation of TEAD4 expression and prostate carcinogenesis, targeting TEAD4 may be beneficially used to enhance arginine-deprivation therapy and prostate cancer therapy.


Assuntos
Arginina/farmacologia , Proteínas de Ligação a DNA/genética , Epigênese Genética/efeitos dos fármacos , Epigenômica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Musculares/genética , Fosforilação Oxidativa/efeitos dos fármacos , Neoplasias da Próstata/genética , Fatores de Transcrição/genética , Animais , Arginina/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Humanos , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Musculares/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/metabolismo
14.
Nat Commun ; 11(1): 3084, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32555153

RESUMO

Tumor-initiating stem-like cells (TICs) are defective in maintaining asymmetric cell division and responsible for tumor recurrence. Cell-fate-determinant molecule NUMB-interacting protein (TBC1D15) is overexpressed and contributes to p53 degradation in TICs. Here we identify TBC1D15-mediated oncogenic mechanisms and tested the tumorigenic roles of TBC1D15 in vivo. We examined hepatocellular carcinoma (HCC) development in alcohol Western diet-fed hepatitis C virus NS5A Tg mice with hepatocyte-specific TBC1D15 deficiency or expression of non-phosphorylatable NUMB mutations. Liver-specific TBC1D15 deficiency or non-p-NUMB expression reduced TIC numbers and HCC development. TBC1D15-NuMA1 association impaired asymmetric division machinery by hijacking NuMA from LGN binding, thereby favoring TIC self-renewal. TBC1D15-NOTCH1 interaction activated and stabilized NOTCH1 which upregulated transcription of NANOG essential for TIC expansion. TBC1D15 activated three novel oncogenic pathways to promote self-renewal, p53 loss, and Nanog transcription in TICs. Thus, this central regulator could serve as a potential therapeutic target for treatment of HCC.


Assuntos
Proteínas Ativadoras de GTPase/metabolismo , Células-Tronco Neoplásicas/citologia , Receptor Notch1/metabolismo , Adulto , Idoso , Animais , Carcinogênese/patologia , Carcinoma Hepatocelular/metabolismo , Divisão Celular , Linhagem Celular Tumoral , Transferência Ressonante de Energia de Fluorescência , Hepacivirus , Hepatócitos/citologia , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Camundongos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Fosforilação , Receptores Notch/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
15.
Nanomaterials (Basel) ; 8(2)2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29425154

RESUMO

Paper-based analytical devices are an emerging class of lightweight and simple-to-use analytical platform. However, challenges such as instrumental requirements and chemical reagents durability, represent a barrier for less-developed countries and markets. Herein, we report an advanced laminated device using red emitting copper nanocluster and RGB digital analysis for signal improvement. Upon RGB system assistance, the device signal-to-background ratio and the calibration sensitivity are highly enhanced under a filter-free setup. In addition, the calibration sensitivity, limit of detection, and coefficient of determination are on par with those determined by instrumental fluorescence analysis. Moreover, the limitation of using oxidation-susceptible fluorescent nanomaterials is overcome by the introduction of protecting tape barriers, antioxidative sheets, and lamination enclosing. The robustness of device is highly advanced, and the durability is prolonged to more than tenfold.

16.
J Phys Ther Sci ; 29(10): 1865-1868, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29184308

RESUMO

[Purpose] The aim of this study was to determine the intrarater reliability of using ultrasonography as a measurement tool to assess the patella position in a weight-bearing condition. [Subjects and Methods] Ten healthy adults participated in this study. Ultrasonography was used to assess the patella position during step down with the loading knee in flexion (0° and 20°). The distance between the patella and lateral condyle was measured to represent the patella position on the condylar groove. Two measurements were obtained on the first day and the day after 1 week by the same investigator. [Results] Excellent intrarater reliability, ranging from 0.83 to 0.93, was shown in both conditions. Standard errors of the measurements were 0.5 mm in the straight knee and 0.7 mm in the knee flexion at 20°. Minimal differences in knee flexion at 0° and knee flexion at 20° were 1.5 mm and 1.9 mm, respectively. [Conclusion] Ultrasonography is a reliable assessment tool for evaluating the positional changes of the patella in weight-bearing activities, and it can be easily used by practitioners in the clinical setting.

17.
ACS Chem Biol ; 12(5): 1335-1345, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28318221

RESUMO

N-glycosylation on IgG modulates Fc conformation and effector functions. An IgG-Fc contains a human sialo-complex type (hSCT) glycan of biantennary structure with two α2,6-sialylations and without core-fucosylation is an optimized glycoform developed to enhance the antibody dependent cellular cytotoxicity (ADCC). hSCT modification not only enhances the binding affinity to Fc receptors in the presence of antigen but also in some cases provides gain-of-function effector activity. We used enzymatic glyco-engineering to prepare an IgG-Fc with homogeneous hSCT attached to each CH2 domain and solved its crystal structure. A compact form and an open form were observed in an asymmetric unit in the crystal. In the compact structure, the double glycan latches from the two hSCT chains stabilize the CH2 domains in a closed conformation. In the open structure, the terminal sialic acid (N-acetylneuraminic acid or NeuNAc) residue interacts through water-mediated hydrogen bonds with the D249-L251 helix, to modulate the pivot region of the CH2-CH3 interface. The double glycan latches and the sialic acid modulation may be mutually exclusive. This is the first crystal structure of glyco-engineered Fc with enhanced effector activities. This work provides insights into the relationship between the structural stability and effector functions affected by hSCT modification and the development of better antibodies for therapeutic applications.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Fragmentos Fc das Imunoglobulinas/química , Imunoglobulina G/química , Polissacarídeos/química , Engenharia de Proteínas/métodos , Cristalografia por Raios X , Desenho de Fármacos , Glicosilação , Humanos , Estrutura Molecular , Ácido N-Acetilneuramínico/química
18.
Nat Commun ; 8: 13882, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28067225

RESUMO

B-cell infection by hepatitis C virus (HCV) has been a controversial topic. To examine whether HCV has a genetically determined lymphotropism through a co-receptor specific for the infection by lymphotropic HCV, we established an infectious clone and chimeric virus of hepatotropic and lymphotropic HCV strains derived from an HCV-positive B-cell lymphoma. The viral envelope and 5'-UTR sequences of the lymphotropic HCV strain were responsible for the lymphotropism. Silencing of the virus sensor, RIGI, or overexpression of microRNA-122 promoted persistent viral replication in B cells. By cDNA library screening, we identified an immune cell-specific, co-stimulatory receptor B7.2 (CD86) as a co-receptor of lymphotropic HCV. Infection of B cells by HCV inhibited the recall reaction to antigen stimulation. Together, a co-receptor B7.2 enabled lymphotropic HCV to infect memory B cells, leading to inhibition of memory B-cell function and persistent HCV infection in HCV-infected hosts.


Assuntos
Linfócitos B/virologia , Antígeno B7-2/genética , Hepacivirus/imunologia , Interações Hospedeiro-Patógeno , Proteínas do Envelope Viral/genética , Tropismo Viral/imunologia , Linfócitos B/imunologia , Antígeno B7-2/imunologia , Linhagem Celular Tumoral , Proteína DEAD-box 58/antagonistas & inibidores , Proteína DEAD-box 58/genética , Proteína DEAD-box 58/imunologia , Regulação da Expressão Gênica , Biblioteca Gênica , Células HEK293 , Células Hep G2 , Humanos , Memória Imunológica , Helicase IFIH1 Induzida por Interferon/genética , Helicase IFIH1 Induzida por Interferon/imunologia , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , MicroRNAs/imunologia , Ligação Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores Imunológicos , Transdução de Sinais , Proteínas do Envelope Viral/imunologia , Replicação Viral
20.
Sci Rep ; 6: 25740, 2016 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-27169898

RESUMO

Gout is characterized by the monosodium urate monohydrate (MSU)-induced arthritis. Alpha kinase-1 (ALPK1) has shown to be associated with MSU-induced inflammation and gout. Here, we used bioinformatics, proteomics, cell models, and twenty in vitro human assays to clarify some of its role in the inflammatory response to MSU. We found myosin IIA to be a frequent interacting protein partner of ALPK1, binding to its N-terminal and forming a protein complex with calmodulin and F-actin, and that MSU-induced ALPK1 phosphorylated the myosin IIA. A knockdown of endogenous ALPK1 or myosin IIA significantly reduced the MSU-induced secretion of tumour necrosis factor (TNF)-α. Furthermore, all gouty patients expressed higher basal protein levels of ALPK1, myosin IIA, and plasma TNF-α, however those medicated with colchicine has shown reduced myosin IIA and TNF-α but not ALPK1. The findings suggest ALPK1 is a kinase that participates in the regulation of Golgi-derived TNF-α trafficking through myosin IIA phosphorylation in the inflammation of gout. This novel pathway could be blocked at the level of myosin by colchicine in gout treatment.


Assuntos
Gota/metabolismo , Miosina não Muscular Tipo IIA/metabolismo , Proteínas Quinases/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Sequência de Aminoácidos , Linhagem Celular , Colchicina/farmacologia , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Vetores Genéticos/metabolismo , Gota/sangue , Células HEK293 , Humanos , Modelos Biológicos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos , Proteínas Quinases/química , Estrutura Secundária de Proteína , Fator de Necrose Tumoral alfa/sangue , Ácido Úrico/farmacologia
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