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1.
J Extracell Vesicles ; 13(10): e12510, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39330928

RESUMEN

This systematic review examines the landscape of extracellular vesicle (EV)-related clinical trials to elucidate the field's trends in clinical applications and EV-related methodologies, with an additional focus on the acknowledgement of EV subpopulations. By analysing data from public reporting repositories, we catalogued 471 EV-related clinical trials to date, with indications for over 200 diseases. Diagnostics and companion diagnostics represented the bulk of EV-related clinical trials with cancer being the most frequent application. EV-related therapeutics trials mainly utilized mesenchymal stromal cell (MSC) EVs and were most frequently used for treatment of respiratory illnesses. Ultracentrifugation and RNA-sequencing were the most common isolation and characterization techniques; however, methodology for each was not frequently reported in study records. Most of the reported characterization relied on bulk characterization of EV isolates, with only 11% utilizing EV subpopulations in their experimental design. While this may be connected to a lack of available techniques suitable for clinical implementation, it also highlights the opportunity for use of EV subpopulations to improve translational efforts. As academic research identifies more chemically distinct subpopulations and technologies for their enrichment, we forecast to more refined EV trials in the near future. This review emphasizes the need for meticulous methodological reporting and consideration of EV subpopulations to enhance the translational success of EV-based interventions, pointing towards a paradigm shift in personalized medicine.


Asunto(s)
Ensayos Clínicos como Asunto , Vesículas Extracelulares , Humanos , Vesículas Extracelulares/metabolismo , Neoplasias/terapia , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología
2.
Nucleic Acids Res ; 51(21): 11927-11940, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37870446

RESUMEN

In various autoimmune diseases, dysfunctional TREX1 (Three prime Repair Exonuclease 1) leads to accumulation of endogenous single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and DNA/RNA hybrids in the cytoplasm and triggers immune activation through the cGAS-STING pathway. Although inhibition of TREX1 could be a useful strategy for cancer immunotherapy, profiling cellular functions in terms of its potential substrates is a key step. Particularly important is the functionality of processing DNA/RNA hybrids and RNA substrates. The exonuclease activity measurements conducted here establish that TREX1 can digest both ssRNA and DNA/RNA hybrids but not dsRNA. The newly solved structures of TREX1-RNA product and TREX1-nucleotide complexes show that 2'-OH does not impose steric hindrance or specific interactions for the recognition of RNA. Through all-atom molecular dynamics simulations, we illustrate that the 2'-OH-mediated intra-chain hydrogen bonding in RNA would affect the binding with TREX1 and thereby reduce the exonuclease activity. This notion of higher conformational rigidity in RNA leading TREX1 to exhibit weaker catalytic cleavage is further validated by the binding affinity measurements with various synthetic DNA-RNA junctions. The results of this work thus provide new insights into the mechanism by which TREX1 processes RNA and DNA/RNA hybrids and contribute to the molecular-level understanding of the complex cellular functions of TREX1 as an exonuclease.


Asunto(s)
ADN , ARN , ADN/genética , ADN/metabolismo , ADN de Cadena Simple/genética , Exodesoxirribonucleasas/metabolismo , Fosfoproteínas/metabolismo , ARN/genética , Animales , Ratones
3.
World J Biol Psychiatry ; 24(9): 822-828, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37139744

RESUMEN

OBJECTIVES: Major depression (MD) may be associated with inflammation and immunity. PD-1 (programmed death-1), PD-L1 (programmed death-ligand 1) and PD-L2 (programmed death-ligand 2) are among the inhibitory immune mediators on the PD-1 pathway. However, previous data regarding the association between MD and PD-1 pathway were still scarce; therefore, we investigated the association of PD-1 pathway with MD. METHODS: During a period of 2 years, patients with MD and healthy controls were recruited from a medical centre in this study. The diagnosis of MD was established according to the DSM-5 criteria. The severity of MD was assessed with 17-item Hamilton Depression Rating Scale. PD-1, PD-L1 and PD-L2 were detected in peripheral blood from MD patients after 4 weeks of treatment with antidepressant drugs. RESULTS: A total of 54 patients with MD and 38 healthy controls were recruited. According to the analyses, there is a significantly higher PD-L2 level in MD than in healthy controls and lower PD-1 level after age and BMI adjustment. Besides, moderately positive correlation between HAM-D scores and PD-L2 level was found. CONCLUSIONS: It was found that PD-1 pathway might play an important role in MD. We need a large sample to prove these results in the future.


Asunto(s)
Trastorno Depresivo Mayor , Humanos , Antígeno B7-H1 , Depresión , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Receptor de Muerte Celular Programada 1
4.
Cancer Med ; 12(11): 12354-12364, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37062070

RESUMEN

BACKGROUND: Taiwanese patients frequently experience severe hepatotoxicity associated with high-dose methotrexate (HD-MTX) treatment, which interferes with subsequent treatment. Drug-drug interactions occur when MTX is used in combination with proton pump inhibitors (PPIs), trimethoprim-sulfamethoxazole (TMP-SMX), or non-steroidal anti-inflammatory drugs (NSAIDs). In East Asia, real-world analyses on the effects of co-medication and other potential risk factors on the clinical course of HD-MTX-mediated acute hepatotoxicity in patients with osteogenic sarcoma (OGS) are limited. METHODS: This cohort study included patients with newly diagnosed OGS who were treated with HD-MTX between 2009 and 2017 at Taipei Veterans General Hospital. We collected data on the clinical course of HD-MTX-mediated acute hepatotoxicity, co-medications, and other potential risk factors, and analyzed the effects of these factors on the clinical course of HD-MTX-mediated acute hepatotoxicity. RESULTS: Almost all patients with OGS treated with HD-MTX developed acute hepatotoxicity with elevated alanine aminotransferase (ALT) levels. Most patients with Grade 3-4 ALT elevation failed to recover to Grade 2 within 7 days. Women and children are high-risk subgroups for HD-MTX-mediated elevation of ALT levels. Age is a factor that contributes to the pharmacokinetic differences of HD-MTX. However, the concurrent use of PPIs, TMP-SMX, or NSAIDs did not affect the elimination of MTX when administered with adequate supportive therapy. CONCLUSIONS: Co-administration of PPIs, TMP-SMX, or NSAIDs may have limited effects on acute hepatotoxicity in well-monitored and adequately pre-medicated patients with OGS undergoing chemotherapy with HD-MTX. Clinicians should pay particular attention to ALT levels when prescribing HD-MTX to children and women.


Asunto(s)
Neoplasias Óseas , Enfermedad Hepática Inducida por Sustancias y Drogas , Osteosarcoma , Niño , Humanos , Femenino , Metotrexato , Combinación Trimetoprim y Sulfametoxazol/efectos adversos , Estudios de Cohortes , Osteosarcoma/tratamiento farmacológico , Antiinflamatorios no Esteroideos , Inhibidores de la Bomba de Protones/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Factores de Riesgo , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Progresión de la Enfermedad
5.
Adv Mater ; 35(13): e2208966, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36609913

RESUMEN

Extracellular vesicles (EVs) are released by cells to mediate intercellular communication under pathological and physiological conditions. While small EVs (sEVs; <100-200 nm, exosomes) are intensely investigated, the properties and functions of medium and large EVs (big EVs (bEVs); >200 nm, microvesicles) are less well explored. Here, bEVs and sEVs are identified as distinct EV populations, and it is determined that bEVs are released in a greater bEV:sEV ratio in the aggressive human triple-negative breast cancer (TNBC) subtype. PalmGRET, bioluminescence-resonance-energy-transfer (BRET)-based EV reporter, reveals dose-dependent EV biodistribution at nonlethal and physiological EV dosages, as compared to lipophilic fluorescent dyes. Remarkably, the bEVs and sEVs exhibit unique biodistribution profiles, yet individually promote in vivo tumor growth in a syngeneic immunocompetent TNBC breast tumor murine model. The bEVs and sEVs share mass-spectrometry-identified tumor-progression-associated EV surface membrane proteins (tpEVSurfMEMs), which include solute carrier family 29 member 1, Cd9, and Cd44. tpEVSurfMEM depletion attenuates EV lung organotropism, alters biodistribution, and reduces protumorigenic potential. This study identifies distinct in vivo property and function of bEVs and sEVs in breast cancer, which suggest the significant role of bEVs in diseases, diagnostic and therapeutic applications.


Asunto(s)
Exosomas , Vesículas Extracelulares , Neoplasias de la Mama Triple Negativas , Ratones , Humanos , Animales , Distribución Tisular , Proteínas de la Membrana/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Vesículas Extracelulares/metabolismo , Exosomas/metabolismo , Carcinogénesis/metabolismo
6.
J Hematol Oncol ; 15(1): 85, 2022 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-35794621

RESUMEN

BACKGROUND: Metastasis and chemoresistance are major culprits of cancer mortality, but factors contributing to these processes are incompletely understood. METHODS: Bioinformatics methods were used to identify the relations of Smyca expression to clinicopathological features of human cancers. RNA-sequencing analysis was used to reveal Smyca-regulated transcriptome. RNA pull-down and RNA immunoprecipitation were used to examine the binding of Smyca to Smad3/4 and c-Myc/Max. Chromatin immunoprecipitation and chromatin isolation by RNA purification were used to determine the binding of transcription factors and Smyca to various gene loci, respectively. Real-time RT-PCR and luciferase assay were used to examine gene expression levels and promoter activities, respectively. Xenograft mouse models were performed to evaluate the effects of Smyca on metastasis and chemoresistance. Nanoparticle-assisted gapmer antisense oligonucleotides delivery was used to target Smyca in vivo. RESULTS: We identify lncRNA Smyca for its association with poor prognosis of many cancer types. Smyca potentiates metabolic reprogramming, migration, invasion, cancer stemness, metastasis and chemoresistance. Mechanistically, Smyca enhances TGF-ß/Smad signaling by acting as a scaffold for promoting Smad3/Smad4 association and further serves as a Smad target to amplify/prolong TGF-ß signaling. Additionally, Smyca potentiates c-Myc-mediated transcription by enhancing the recruitment of c-Myc/Max complex to a set of target promoters and c-Myc binding to TRRAP. Through potentiating TGF-ß and c-Myc pathways, Smyca synergizes the Warburg effect elicited by both pathways but evades the anti-proliferative effect of TGF-ß. Targeting Smyca prevents metastasis and overcomes chemoresistance. CONCLUSIONS: This study uncovers a lncRNA that coordinates tumor-relevant pathways to orchestra a pro-tumor program and establishes the clinical values of Smyca in cancer prognosis and therapy.


Asunto(s)
Neoplasias , ARN Largo no Codificante , Animales , Humanos , Ratones , Regiones Promotoras Genéticas , ARN Largo no Codificante/genética , Factor de Crecimiento Transformador beta/metabolismo
7.
Psychiatry Investig ; 19(7): 511-518, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35903053

RESUMEN

OBJECTIVE: The Schizophrenia Cognition Rating Scale (SCoRS) is an interview-based assessment tool for evaluating the cognitive deficit and daily functioning of patients with schizophrenia. METHODS: Sixty-eight patients with schizophrenia and 68 age- and sex-matched healthy individuals were recruited to validate the Chinese version of SCoRS in this study. All participants underwent cognitive assessment using the SCoRS, which was verified by the Brief Assessment of Cognition in Schizophrenia (BACS), and the UCSD Performance-based Skills Assessment, Brief Version (UPSA-B). Patients with schizophrenia were additionally assessed using the Positive and Negative Syndrome Scale (PANSS). RESULTS: SCoRS ratings reported by patients (SCoRS-S), those reported by the interviewer (SCoRS-I), and SCoRS global scores (SCoRS-G) showed significant correlation with all subscales of the BACS and the UPSA-B. On receiver operating characteristic curve analysis, SCoRS-S, SCoRS-I, and SCoRS-G significantly differentiated patients with schizophrenia from healthy controls. Moreover, SCoRS-S and SCoRS-I ratings showed positive correlation with the negative symptoms and general symptoms of PANSS. CONCLUSION: The Chinese version of SCoRS showed good discriminant, concurrent, and external validity, suggesting that it is a useful and convenient tool for assessment of cognitive function among Mandarin-speaking patients with schizophrenia in clinical practice.

8.
J Control Release ; 346: 169-179, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35429575

RESUMEN

Fibrosis is an excessive accumulation of the extracellular matrix within solid organs in response to injury and a common pathway that leads functional failure. No clinically approved agent is available to reverse or even prevent this process. Herein, we report a nanotechnology-based approach that utilizes a drug carrier to deliver a therapeutic cargo specifically to fibrotic kidneys, thereby improving the antifibrotic effect of the drug and reducing systemic toxicity. We first adopted in vitro-in vivo combinatorial phage display technology to identify peptide ligands that target myofibroblasts in mouse unilateral ureteral obstruction (UUO)-induced fibrotic kidneys. We then engineered lipid-coated poly(lactic-co-glycolic acid) nanoparticles (NPs) with fibrotic kidney-homing peptides on the surface and sorafenib, a potent antineoplastic multikinase inhibitor, encapsulated in the core. Sorafenib loaded in the myofibroblast-targeted NPs significantly reduced the infiltration of α-smooth muscle actin-expressing myofibroblasts and deposition of collagen I in UUO-treated kidneys and enhanced renal plasma flow measured by Technetium-99m mercaptoacetyltriglycine scintigraphy. This study demonstrates the therapeutic potential of the newly identified peptide fragments as anchors to target myofibroblasts and represents a strategic advance for selective delivery of sorafenib to treat renal fibrosis. SIGNIFICANCE STATEMENT: Renal fibrosis is a pathological feature accounting for the majority of issues in chronic kidney disease (CKD), which may progress to end-stage renal disease (ESRD). This manuscript describes a myofibroblast-targeting drug delivery system modified with phage-displayed fibrotic kidney-homing peptides. By loading the myofibroblast-targeting nanoparticles (NPs) with sorafenib, a multikinase inhibitor, the NPs could suppress collagen synthesis in cultured human myofibroblasts. When given intravenously to mice with UUO-induced renal fibrosis, sorafenib loaded in myofibroblast-targeting NPs significantly ameliorated renal fibrosis. This approach provides an efficient therapeutic option to renal fibrosis. The myofibroblast-targeting peptide ligands and nanoscale drug carriers may be translated into clinical application in the future.


Asunto(s)
Enfermedades Renales , Nanopartículas , Obstrucción Ureteral , Animales , Colágeno , Modelos Animales de Enfermedad , Portadores de Fármacos/uso terapéutico , Fibrosis , Riñón , Enfermedades Renales/patología , Ligandos , Ratones , Ratones Endogámicos C57BL , Miofibroblastos , Sorafenib/uso terapéutico , Obstrucción Ureteral/tratamiento farmacológico , Obstrucción Ureteral/patología
9.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-33753481

RESUMEN

The CXC chemokine receptor type 4 (CXCR4) receptor and its ligand, CXCL12, are overexpressed in various cancers and mediate tumor progression and hypoxia-mediated resistance to cancer therapy. While CXCR4 antagonists have potential anticancer effects when combined with conventional anticancer drugs, their poor potency against CXCL12/CXCR4 downstream signaling pathways and systemic toxicity had precluded clinical application. Herein, BPRCX807, known as a safe, selective, and potent CXCR4 antagonist, has been designed and experimentally realized. In in vitro and in vivo hepatocellular carcinoma mouse models it can significantly suppress primary tumor growth, prevent distant metastasis/cell migration, reduce angiogenesis, and normalize the immunosuppressive tumor microenvironment by reducing tumor-associated macrophages (TAMs) infiltration, reprogramming TAMs toward an immunostimulatory phenotype and promoting cytotoxic T cell infiltration into tumor. Although BPRCX807 treatment alone prolongs overall survival as effectively as both marketed sorafenib and anti-PD-1, it could synergize with either of them in combination therapy to further extend life expectancy and suppress distant metastasis more significantly.


Asunto(s)
Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Receptores CXCR4/antagonistas & inhibidores , Animales , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Dietilnitrosamina/administración & dosificación , Dietilnitrosamina/toxicidad , Sinergismo Farmacológico , Humanos , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/inmunología , Neoplasias Hepáticas Experimentales/patología , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/inmunología , Masculino , Ratones , Simulación del Acoplamiento Molecular , Ratas , Receptores CXCR4/metabolismo , Transducción de Señal/efectos de los fármacos , Sorafenib/farmacología , Sorafenib/uso terapéutico , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Macrófagos Asociados a Tumores/efectos de los fármacos , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
10.
JACS Au ; 1(12): 2315-2327, 2021 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-34977900

RESUMEN

For using targeted covalent inhibitors (TCIs) as anticancer and antiviral drugs, we establish that the model compounds PCMPS (p-chloromercuriphenyl sulfate) and PCMB (p-chloromercuribenzoate) are inhibitors of the DEDDh family of exonucleases. The underlying mechanism is analyzed by X-ray crystallography, activity/nucleic acid-binding assays, and all-atom molecular dynamics (MD) simulations. The first TCI-complexed structures of a DEDDh enzyme, the Lassa fever virus NP exonuclease (NPexo), are resolved to elucidate that the Cys409 binding site is away from the active site and the RNA-binding lid. The NPexo C409A structures indicate Cys461 as the alternative distal site for obstructing the equally active mutant. All-atom MD simulations of the wild type and mutant NPexos in explicit solvent uncover an allosteric inhibition mechanism that the local perturbation induced by PCMPS sulfonate propagates to impact the RNA-binding lid conformation. Binding assay studies confirm that PCMPS does affect the RNA binding of NPexo. The predicted relative potency between PCMPS and PCMB is also in line with experiments. The structural data and inhibition mechanism established in this work provide an important molecular basis for the drug development of TCIs.

11.
Polymers (Basel) ; 12(9)2020 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-32899178

RESUMEN

Bio-based unsaturated poly(butylene adipate-co-butylene itaconate) (PBABI) aliphatic copolyesters were synthesized with pentaerythritol (PE) as a modifier, observing the melting point, crystallization, and glass transition temperatures were decreased from 59.5 to 19.5 °C and 28.2 to -9.1 °C as an increase of itaconate concentration, and Tg ranged from -54.6 to -48.1 °C. PBABI copolyesters tend to the amorphous state by the existence of the BI unit above 40 mol%. The yield strength, elongation, and Young's modulus at different BA/BI ratios were valued in a range of 13.2-13.8 MPa, 575.2-838.5%, and 65.1-83.8 MPa, respectively. Shear-thinning behavior was obtained in all BA/BI ratios of PBABI copolyesters around an angular frequency range of 20-30 rad s-1. Furthermore, the thermal and mechanical properties of PBABI copolyesters can be well regulated via controlling the itaconic acid contents and adding the modifier. PBABI copolyesters can be coated on a 3D air mesh polyester fabric to reinforce the mechanical property for replacing traditional plaster applications.

12.
Polymers (Basel) ; 12(5)2020 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-32438555

RESUMEN

Unsaturated poly (butylene adipate-co-butylene itaconate) (PBABI) copolyesters were synthesized through melt polymerization composed of 1,4-butanediol (BDO), adipic acid (AA), itaconic acid (IA) and 1,2,4,5-benzenetetracarboxylic acid (BTCA) as a cross-linking modifier. The melting point, crystallization and glass transition temperature of the PBABI copolyesters were detected around 29.8-49 °C, 7.2-29 °C and -51.1 and -58.1 °C, respectively. Young's modulus can be modified via partial cross-linking by BTCA in the presence of IA, ranging between 32.19-168.45 MPa. Non-isothermal crystallization kinetics were carried out to explore the crystallization behavior, revealing the highest crystallization rate was placed in the BA/BI = 90/10 at a given molecular weight. Furthermore, the thermal, mechanical properties, and crystallization rate of PBABI copolyesters can be tuned through the adjustment of BTCA and IA concentrations.

13.
Sci Adv ; 6(3): eaax5032, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31998834

RESUMEN

While immunotherapy holds great promise for combating cancer, the limited efficacy due to an immunosuppressive tumor microenvironment and systemic toxicity hinder the broader application of cancer immunotherapy. Here, we report a combinatorial immunotherapy approach that uses a highly efficient and tumor-selective gene carrier to improve anticancer efficacy and circumvent the systemic toxicity. In this study, we engineered tumor-targeted lipid-dendrimer-calcium-phosphate (TT-LDCP) nanoparticles (NPs) with thymine-functionalized dendrimers that exhibit not only enhanced gene delivery capacity but also immune adjuvant properties by activating the stimulator of interferon genes (STING)-cGAS pathway. TT-LDCP NPs delivered siRNA against immune checkpoint ligand PD-L1 and immunostimulatory IL-2-encoding plasmid DNA to hepatocellular carcinoma (HCC), increased tumoral infiltration and activation of CD8+ T cells, augmented the efficacy of cancer vaccine immunotherapy, and suppressed HCC progression. Our work presents nanotechnology-enabled dual delivery of siRNA and plasmid DNA that selectively targets and reprograms the immunosuppressive tumor microenvironment to improve cancer immunotherapy.


Asunto(s)
Biomarcadores de Tumor , Fenómenos Inmunogenéticos , Terapia Molecular Dirigida , Nanopartículas , Neoplasias/genética , Neoplasias/inmunología , Neoplasias/terapia , Nanomedicina Teranóstica , Animales , Antineoplásicos Inmunológicos/uso terapéutico , Biomarcadores/metabolismo , Fosfatos de Calcio/química , Citocinas/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Células Dendríticas/patología , Sistemas de Liberación de Medicamentos , Técnicas de Transferencia de Gen , Terapia Genética , Humanos , Inmunoterapia , Lípidos/química , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Nanopartículas/química , Nanopartículas/ultraestructura , Nanotecnología , Neoplasias/patología , Plásmidos/administración & dosificación , Plásmidos/química , Plásmidos/genética , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/química , ARN Interferente Pequeño/genética , Transducción de Señal
14.
Nucleic Acids Res ; 46(22): 12166-12176, 2018 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-30357414

RESUMEN

The three prime repair exonuclease 2 (TREX2) is an essential 3'-to-5' exonuclease that functions in cell proliferation, genome integrity and skin homeostasis maintenance. The abnormal expression level of TREX2 can result in broken chromosome, increased susceptibility to skin carcinogenesis and Psoriasis. However, the molecular mechanisms of how TREX2 binds and processes its natural substrates, dsDNA or chromosomal DNA, to maintain genome stability remain unclear. In this study, we present four new crystal structures: apo-TREX2, TREX2 in complex with two different dsDNA substrates, and TREX2 in complex with a processed dsDNA product. Analysis of the structures reveals that TREX2 stacks with the 5'-terminal of dsDNA by a Leu20-Pro21-Asn22 cluster for precisely trimming the 3'-overhang. In addition, TREX2 specifically interacts with the non-scissile strand of dsDNA by an α-helix-loop region. The unique interaction patterns of the TREX2-dsDNA complex highlight the requirement of long double-stranded region for TREX2 binding and provide evidence of the functional role of TREX2 in processing chromosomal DNA. Moreover, the non-processive property of TREX2 is elucidated by the structure of TREX2-product complex. Our work discloses the first structural basis of the molecular interactions between TREX2 and its substrates and unravels the mechanistic actions of TREX2.


Asunto(s)
Apoproteínas/química , ADN/química , Exodesoxirribonucleasas/química , Subunidades de Proteína/química , Secuencias de Aminoácidos , Animales , Apoproteínas/genética , Apoproteínas/metabolismo , Dominio Catalítico , Clonación Molecular , Cristalografía por Rayos X , ADN/genética , ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Exodesoxirribonucleasas/genética , Exodesoxirribonucleasas/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Ratones , Modelos Moleculares , Conformación de Ácido Nucleico , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato
15.
Biomacromolecules ; 19(6): 2330-2339, 2018 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-29808997

RESUMEN

Successful siRNA therapy requires suitable delivery systems with targeting moieties such as small molecules, peptides, antibodies, or aptamers. Galactose (Gal) residues recognized by the asialoglycoprotein receptor (ASGPR) can serve as potent targeting moieties for hepatocellular carcinoma (HCC) cells. However, efficient targeting to HCC via galactose moieties rather than normal liver tissues in HCC patients remains a challenge. To achieve more efficient siRNA delivery in HCC, we synthesized various galactoside derivatives and investigated the siRNA delivery capability of nanoparticles modified with those galactoside derivatives. In this study, we assembled lipid/calcium/phosphate nanoparticles (LCP NPs) conjugated with eight types of galactoside derivatives and demonstrated that phenyl ß-d-galactoside-decorated LCP NPs (L4-LCP NPs) exhibited a superior siRNA delivery into HCC cells compared to normal hepatocytes. VEGF siRNAs delivered by L4-LCP NPs downregulated VEGF expression in HCC in vitro and in vivo and led to a potent antiangiogenic effect in the tumor microenvironment of a murine orthotopic HCC model. The efficient delivery of VEGF siRNA by L4-LCP NPs that resulted in significant tumor regression indicates that phenyl galactoside could be a promising HCC-targeting ligand for therapeutic siRNA delivery to treat liver cancer.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Galactosa , Neoplasias Hepáticas/tratamiento farmacológico , Nanopartículas , ARN Interferente Pequeño , Animales , Receptor de Asialoglicoproteína/antagonistas & inhibidores , Receptor de Asialoglicoproteína/biosíntesis , Receptor de Asialoglicoproteína/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Galactosa/química , Galactosa/farmacología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Nanopartículas/química , Nanopartículas/uso terapéutico , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , ARN Interferente Pequeño/química , ARN Interferente Pequeño/farmacología , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/genética
16.
PLoS Biol ; 16(5): e2005653, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29734329

RESUMEN

Three prime repair exonuclease 1 (TREX1) is an essential exonuclease in mammalian cells, and numerous in vivo and in vitro data evidenced its participation in immunity regulation and in genotoxicity remediation. In these very complicated cellular functions, the molecular mechanisms by which duplex DNA substrates are processed are mostly elusive because of the lack of structure information. Here, we report multiple crystal structures of TREX1 complexed with various substrates to provide the structure basis for overhang excision and terminal unwinding of DNA duplexes. The substrates were designed to mimic the intermediate structural DNAs involved in various repair pathways. The results showed that the Leu24-Pro25-Ser26 cluster of TREX1 served to cap the nonscissile 5'-end of the DNA for precise removal of the short 3'-overhang in L- and Y-structural DNA or to wedge into the double-stranded region for further digestion along the duplex. Biochemical assays were also conducted to demonstrate that TREX1 can indeed degrade double-stranded DNA (dsDNA) to a full extent. Overall, this study provided unprecedented knowledge at the molecular level on the enzymatic substrate processing involved in prevention of immune activation and in responses to genotoxic stresses. For example, Arg128, whose mutation in TREX1 was linked to a disease state, were shown to exhibit consistent interaction patterns with the nonscissile strand in all of the structures we solved. Such structure basis is expected to play an indispensable role in elucidating the functional activities of TREX1 at the cellular level and in vivo.


Asunto(s)
Reparación del ADN , ADN de Cadena Simple/metabolismo , Exodesoxirribonucleasas/metabolismo , Fosfoproteínas/metabolismo , Animales , Ratones
17.
Oncotarget ; 9(24): 17210-17219, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29682217

RESUMEN

Leptin is a peptide hormone that has been characterized as the ligand of leptin receptor (LEPR). The observation of leptin secretion and leptin receptor expression beyond the normal tissues suggests the potentially critical roles other than its physiological function. In addition to the original function in controlling appetite and energy expenditure, leptin-mediated signaling axis through leptin receptor is multifunctional which plays role in the regulation toward broad types of cancer. Emerging evidences has indicated leptin's function in promoting several processes which are relevant to cancer progression including cell proliferation, metastasis, angiogenesis and drug resistance. We relatively display leptin and leptin receptor expression levels in pan-cancer panel based on the transcriptome analysis via dataset The Cancer Genome Atlas (TCGA), and show the clinical association of the axis in predicting cancer prognosis. The results indicate the pathological impacts of this axis on many types of cancer. This review mainly focuses on leptin-mediated effects and its downstream signaling related to the progression of cancers, and displays the clinical significance of this axis including the impact on cancer patient survival.

18.
Hepatology ; 67(3): 899-913, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28885731

RESUMEN

The anticancer efficacy of TNF-related apoptosis-inducing ligand (TRAIL)-based therapy is limited because of systemic toxicity, poor bioavailability, and development of TRAIL resistance. We developed a tumor-targeted LCPP (lipid/calcium/phosphate/protamine) nanoparticle (NP) to deliver TRAIL plasmid DNA (pDNA) into hepatocellular carcinoma (HCC) cells in a mouse model of HCC. TRAIL pDNA was encapsulated in a pH stimuli-responsive calcium phosphate (CaP) core, and protamine was added to facilitate nuclear delivery of pDNA. In addition, intracellular release of Ca2+ from the CaP core overcame TRAIL resistance by calcium influx-dependent DR5 up-regulation. TRAIL expression also attenuated fibrosis in liver tissues surrounding HCCs by reverting activated hepatic stellate cells (HSCs) to a quiescent state or by directly inducing apoptosis in activated HSCs. CONCLUSION: TRAIL pDNA delivered by HCC-targeted LCPP NPs in combination with conventional sorafenib treatment attenuated HCC progression as well as liver fibrosis. Overall, our study presents an effective TRAIL-based cancer therapy that could be developed for clinical applications. (Hepatology 2018;67:899-913).


Asunto(s)
Carcinoma Hepatocelular/terapia , Terapia Genética/métodos , Neoplasias Hepáticas/terapia , Terapia Molecular Dirigida/métodos , Nanopartículas/administración & dosificación , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Animales , Apoptosis , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Neoplasias Hepáticas/patología , Masculino , Ratones , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo
19.
J Med Chem ; 59(17): 8019-29, 2016 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-27529560

RESUMEN

The DEDDh family of exonucleases plays essential roles in DNA and RNA metabolism in all kingdoms of life. Several viral and human DEDDh exonucleases can serve as antiviral drug targets due to their critical roles in virus replication. Here using RNase T and CRN-4 as the model systems, we identify potential inhibitors for DEDDh exonucleases. We further show that two of the inhibitors, ATA and PV6R, indeed inhibit the exonuclease activity of the viral protein NP exonuclease of Lassa fever virus in vitro. Moreover, we determine the crystal structure of CRN-4 in complex with MES that reveals a unique inhibition mechanism by inducing the general base His179 to shift out of the active site. Our results not only provide the structural basis for the inhibition mechanism but also suggest potential lead inhibitors for the DEDDh exonucleases that may pave the way for designing nuclease inhibitors for biochemical and biomedical applications.


Asunto(s)
Ácidos Alcanesulfónicos/química , Exonucleasas/antagonistas & inhibidores , Morfolinas/química , Proteínas de Caenorhabditis elegans/antagonistas & inhibidores , Proteínas de Caenorhabditis elegans/química , Dominio Catalítico , Cristalografía por Rayos X , ADN de Cadena Simple/química , Endodesoxirribonucleasas/antagonistas & inhibidores , Endodesoxirribonucleasas/química , Exonucleasas/química , Exorribonucleasas/antagonistas & inhibidores , Exorribonucleasas/química , Virus Lassa/enzimología , Simulación del Acoplamiento Molecular , Estructura Molecular , ARN/química , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/química
20.
Light Sci Appl ; 5(4): e16066, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30167160

RESUMEN

The remarkable narrow-band emission of trivalent lanthanide-doped phosphors excited by the vacuum ultraviolet (VUV) radiation lines of Xe atoms/Xe2 molecules at 147/172 nm are extensively investigated in the development of plasma display panels and Hg-free fluorescent lamps, which are frequently used in our daily lives. Numerous solid materials, particularly Tb3+-doped oxides, such as silicates, phosphates and borates, are efficient green/blue sources with color-tunable properties. The excitation wavelength and rare earth concentration are usually varied to optimize efficiency and the luminescent properties. However, some underlying mechanisms for the shift in the emission colors remain unclear. The present study shows that a UV/VUV switch systematically controls the change in the phosphor (Ba3Si6O12N2:Tb) photoluminescence from green to blue, resulting in a green emission when the system is excited with UV radiation. However, a blue color is observed when the radiation wavelength shifts to the VUV region. Thus, a configurational coordinate model is proposed for the color-reversal effect. In this model, the dominant radiative decay results in a green emission under low-energy UV excitation from the 5D4 state of the f-f inner-shell transition in the Tb system. However, under high-energy VUV excitation, the state switches into the 5D3 state, which exhibits a blue emission. This mechanism is expected to be generally applicable to Tb-doped phosphors and useful in adjusting the optical properties against well-known cross-relaxation processes by varying the ratio of the green/blue contributions.

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