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1.
PLoS Pathog ; 20(7): e1012345, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38968329

RESUMEN

The CRISPR-Cas13 system has been proposed as an alternative treatment of viral infections. However, for this approach to be adopted as an antiviral, it must be optimized until levels of efficacy rival or exceed the performance of conventional approaches. To take steps toward this goal, we evaluated the influenza viral RNA degradation patterns resulting from the binding and enzymatic activity of mRNA-encoded LbuCas13a and two crRNAs from a prior study, targeting PB2 genomic and messenger RNA. We found that the genome targeting guide has the potential for significantly higher potency than originally detected, because degradation of the genomic RNA is not uniform across the PB2 segment, but it is augmented in proximity to the Cas13 binding site. The PB2 genome targeting guide exhibited high levels (>1 log) of RNA degradation when delivered 24 hours post-infection in vitro and maintained that level of degradation over time, with increasing multiplicity of infection (MOI), and across modern influenza H1N1 and H3N2 strains. Chemical modifications to guides with potent LbuCas13a function, resulted in nebulizer delivered efficacy (>1-2 log reduction in viral titer) in a hamster model of influenza (Influenza A/H1N1/California/04/09) infection given prophylactically or as a treatment (post-infection). Maximum efficacy was achieved with two doses, when administered both pre- and post-infection. This work provides evidence that mRNA-encoded Cas13a can effectively mitigate Influenza A infections opening the door to the development of a programmable approach to treating multiple respiratory infections.


Asunto(s)
Sistemas CRISPR-Cas , Gripe Humana , Estabilidad del ARN , ARN Mensajero , ARN Viral , Animales , ARN Viral/genética , ARN Viral/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Humanos , Gripe Humana/virología , Subtipo H1N1 del Virus de la Influenza A/genética , Subtipo H3N2 del Virus de la Influenza A/genética , Infecciones por Orthomyxoviridae/virología , Antivirales/farmacología , Perros , Cricetinae , Proteínas Virales/genética , Proteínas Virales/metabolismo , Mesocricetus , Células de Riñón Canino Madin Darby
2.
Nat Mater ; 22(3): 369-379, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36443576

RESUMEN

Messenger RNA has now been used to vaccinate millions of people. However, the diversity of pulmonary pathologies, including infections, genetic disorders, asthma and others, reveals the lung as an important organ to directly target for future RNA therapeutics and preventatives. Here we report the screening of 166 polymeric nanoparticle formulations for functional delivery to the lungs, obtained from a combinatorial synthesis approach combined with a low-dead-volume nose-only inhalation system for mice. We identify P76, a poly-ß-amino-thio-ester polymer, that exhibits increased expression over formulations lacking the thiol component, delivery to different animal species with varying RNA cargos and low toxicity. P76 allows for dose sparing when delivering an mRNA-expressed Cas13a-mediated treatment in a SARS-CoV-2 challenge model, resulting in similar efficacy to a 20-fold higher dose of a neutralizing antibody. Overall, the combinatorial synthesis approach allowed for the discovery of promising polymeric formulations for future RNA pharmaceutical development for the lungs.


Asunto(s)
COVID-19 , Animales , Ratones , ARN Mensajero/genética , SARS-CoV-2/genética , Polímeros/metabolismo , Pulmón , ARN/metabolismo
3.
Mycoses ; 67(5): e13748, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38783563

RESUMEN

BACKGROUND: Dermatophytosis is a common and major public health concern worldwide. Despite the increasing availability of antifungal drugs, relapses and untreated cases of dermatophyte infections are reported. Therefore, novel antifungal agents are required. Aminopyrrolnitrin (APRN) shows promise for dermatophytosis treatment because of its antifungal activity. OBJECTIVES: This study aimed to assess the antifungal properties of APRN against Trichophyton verrucosum (T. verrucosum), in both laboratory settings and a guinea pig model. METHODS: The minimum inhibitory concentrations (MICs) of APRN and enilconazole against T. verrucosum were determined according to the CLSI M38 method. The skins of 16 male guinea pigs were infected with 1.0 × 108 conidia of T. verrucosum and the animals were grouped into sets of four: negative control group (NC) received normal saline; positive control group (PC) received 2 µg/mL of enilconazole; and APRN4 and APRN8 received 4 and 8 µg/mL of APRN, respectively. Clinical, mycological and histological efficacies were measured after 10 days. RESULTS: The MIC90 of APRN and enilconazole against T. verrucosum was 4 and 2 µg/mL, respectively. The clinical scores of PC, APRN4, and APRN8 were significantly lower than those of NC. Clinical and mycological efficacies were higher for APRN8, APRN4 and PC. No fungi were observed in the skin tissues of APRN4 and APRN8, while fungi were observed in 50% of the PC. CONCLUSION: APRN showed antifungal activity against T. verrucosum in vitro and in vivo and is a potential candidate for the treatment of dermatophytosis.


Asunto(s)
Antifúngicos , Modelos Animales de Enfermedad , Pruebas de Sensibilidad Microbiana , Tiña , Trichophyton , Animales , Cobayas , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Trichophyton/efectos de los fármacos , Tiña/tratamiento farmacológico , Tiña/microbiología , Masculino , Piel/microbiología
4.
Nanomedicine ; 44: 102587, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35863620

RESUMEN

Nanodiscs containing sialic acid, which binds the hemagglutinin of the influenza virus, rupture the viral envelope and entrap viral ribonucleoproteins in the endolysosome. While nanodiscs are potent antiviral platforms, ganglioside GD1a containing α2,3-sialic acid does not cover all virus strains. When two nanodiscs containing different receptors 6'-sialyllactose and GD1a were mixed, one nanodisc inhibited the function of the other. A nanodisc loaded with two different receptors exhibited a biased activity toward only one receptor precluding the generation of a multifunctional nanodisc. Here, we suggest hetero di-disc, in which two nanodiscs loaded with each receptor were conjugated through protein trans-splicing for a broad-spectrum antiviral. The hetero di-disc showed strong antiviral activity in vitro and in vivo. Our results suggested that hetero di-discs not only expanded the inhibitory spectrum of nanodiscs but also enabled nanodisc-based delivery of multiple ligands without interference.


Asunto(s)
Gripe Humana , Antivirales/farmacología , Hemaglutininas , Humanos , Gripe Humana/tratamiento farmacológico , Ácido N-Acetilneuramínico/metabolismo
5.
Nano Lett ; 21(6): 2505-2511, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33689385

RESUMEN

Crystalline two-dimensional (2D) superconductors (SCs) with low carrier density are an exciting new class of materials in which electrostatic gating can tune superconductivity, electronic interactions play a prominent role, and electrical transport properties may directly reflect the topology of the Fermi surface. Here, we report the dramatic enhancement of superconductivity with decreasing thickness in semimetallic Td-MoTe2, with critical temperature (Tc) increasing up to 7.6 K for monolayers, a 60-fold increase with respect to the bulk Tc. We show that monolayers possess a similar electronic structure and density of states (DOS) as the bulk, implying that electronic interactions play a strong role in the enhanced superconductivity. Reflecting the low carrier density, the critical temperature, magnetic field, and current density are all tunable by an applied gate voltage. The response to high in-plane magnetic fields is distinct from that of other 2D SCs and reflects the canted spin texture of the electron pockets.

6.
Prostate ; 80(13): 1145-1156, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32659025

RESUMEN

BACKGROUND: Epithelial stem cells (ESCs) demonstrate a capacity to maintain normal tissues homeostasis and ESCs with a deregulated behavior can contribute to cancer development. The ability to reprogram normal tissue epithelial cells into prostate or mammary stem-like cells holds great promise to help understand cell of origin and lineage plasticity in prostate and breast cancers in addition to understanding normal gland development. We previously showed that an intracellular chemokine, CXCL12γ induced cancer stem cells and neuroendocrine characteristics in both prostate and breast adenocarcinoma cell lines. However, its role in normal prostate or mammary epithelial cell fate and development remains unknown. Therefore, we sought to elucidate the functional role of CXCL12γ in the regulation of ESCs and tissue development. METHODS: Prostate epithelial cells (PNT2) or mammary epithelial cells (MCF10A) with overexpressed CXCL12γ was characterized by quantitative real-time polymerase chain reaction, Western blots, and immunofluorescence for lineage marker expression, and fluorescence activated cell sorting analyses and sphere formation assays to examine stem cell surface phenotype and function. Xenotransplantation animal models were used to evaluate gland or acini formation in vivo. RESULTS: Overexpression of CXCL12γ promotes the reprogramming of cells with a differentiated luminal phenotype to a nonluminal phenotype in both prostate (PNT2) and mammary (MCF10A) epithelial cells. The CXCL12γ-mediated nonluminal type cells results in an increase of epithelial stem-like phenotype including the subpopulation of EPCAMLo /CD49fHi /CD24Lo /CD44Hi cells capable of sphere formation. Critically, overexpression of CXCL12γ promotes the generation of robust gland-like structures from both prostate and mammary epithelial cells in in vivo xenograft animal models. CONCLUSIONS: CXCL12γ supports the reprogramming of epithelial cells into nonluminal cell-derived stem cells, which facilitates gland development.


Asunto(s)
Quimiocina CXCL12/biosíntesis , Glándulas Mamarias Humanas/crecimiento & desarrollo , Próstata/crecimiento & desarrollo , Animales , Reprogramación Celular/fisiología , Células Epiteliales/citología , Células Epiteliales/metabolismo , Femenino , Xenoinjertos , Humanos , Masculino , Glándulas Mamarias Humanas/citología , Glándulas Mamarias Humanas/metabolismo , Ratones , Próstata/citología , Próstata/metabolismo , Isoformas de Proteínas
7.
Prostate ; 79(14): 1715-1727, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31449673

RESUMEN

BACKGROUND: Disseminated tumor cells (DTCs) have been reported in the bone marrow (BM) of patients with localized prostate cancer (PCa). However, the existence of these cells continues to be questioned, and few methods exist for viable DTC isolation. Therefore, we sought to develop novel approaches to identify and, if detected, analyze localized PCa patient DTCs. METHODS: We used fluorescence-activated cell sorting (FACS) to isolate a putative DTC population, which was negative for CD45, CD235a, alkaline phosphatase, and CD34, and strongly expressed EPCAM. We examined tumor cell content by bulk cell RNA sequencing (RNA-Seq) and whole-exome sequencing after whole genome amplification. We also enriched for BM DTCs with α-EPCAM immunomagnetic beads and performed quantitative reverse trancriptase polymerase chain reaction (qRT-PCR) for PCa markers. RESULTS: At a threshold of 4 cells per million BM cells, the putative DTC population was present in 10 of 58 patients (17%) with localized PCa, 4 of 8 patients with metastatic PCa of varying disease control, and 1 of 8 patients with no known cancer, and was positively correlated with patients' plasma PSA values. RNA-Seq analysis of the putative DTC population collected from samples above (3 patients) and below (5 patients) the threshold of 4 putative DTCs per million showed increased expression of PCa marker genes in 4 of 8 patients with localized PCa, but not the one normal donor who had the putative DTC population present. Whole-exome sequencing also showed the presence of single nucleotide polymorphisms and structural variants in the gene characteristics of PCa in 2 of 3 localized PCa patients. To examine the likely contaminating cell types, we used a myeloid colony formation assay, differential counts of cell smears, and analysis of the RNA-Seq data using the CIBERSORT algorithm, which most strongly suggested the presence of B-cell lineages as a contaminant. Finally, we used EPCAM enrichment and qRT-PCR for PCa markers to estimate DTC prevalence and found evidence of DTCs in 21 of 44 samples (47%). CONCLUSION: These data support the presence of DTCs in the BM of a subset of patients with localized PCa and describe a novel FACS method for isolation and analysis of viable DTCs.


Asunto(s)
Células de la Médula Ósea/patología , Médula Ósea/patología , Metástasis de la Neoplasia/patología , Neoplasias de la Próstata/patología , Anciano , Biomarcadores de Tumor/análisis , Separación Celular/métodos , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Polimorfismo de Nucleótido Simple/genética , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/genética , Análisis de Secuencia de ARN , Secuenciación del Exoma
8.
Biochem Biophys Res Commun ; 517(3): 507-512, 2019 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-31375212

RESUMEN

Molecules interfering with lipid bilayer function exhibit strong antiviral activity against a broad range of enveloped viruses, with a lower risk of resistance development than that for viral protein-targeting drugs. Amphipathic peptides are rich sources of such membrane-interacting antivirals. Here, we report that influenza viruses were effectively inactivated by M2 AH, an amphipathic peptide derived from the M2 protein of the influenza virus. Although overall hydrophobicity () of M2 AH was not related to antiviral activity, modification of the hydrophobic moment (<µH>) of M2 AH dramatically altered the antiviral activity of this peptide. M2 MH, a derivative of M2 AH with a <µH> of 0.874, showed a half maximal inhibitory concentration (IC50) of 53.3 nM against the A/PR/8/34 strain (H1N1), which is 16-times lower than that of M2 AH. The selectivity index (IC50/CC50), where CC50 is the half maximal cytotoxic concentration, was 360 for M2 MH and 81 for M2 AH. Dynamic light scattering spectroscopy and electron microscopy revealed that M2 AH-derived peptides did not disrupt liposomes but altered the shape of viruses. This result suggests that the shape of virus envelope was closely related to its activity. Thus, we propose that deforming without rupturing the membranes may achieve a high selectivity index for peptide antivirals.


Asunto(s)
Antivirales/farmacología , Membrana Celular/efectos de los fármacos , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Péptidos/farmacología , Proteínas de la Matriz Viral/química , Secuencia de Aminoácidos , Animales , Antivirales/síntesis química , Membrana Celular/química , Membrana Celular/virología , Perros , Interacciones Hidrofóbicas e Hidrofílicas , Subtipo H1N1 del Virus de la Influenza A/crecimiento & desarrollo , Subtipo H1N1 del Virus de la Influenza A/ultraestructura , Concentración 50 Inhibidora , Membrana Dobles de Lípidos/química , Liposomas/química , Células de Riñón Canino Madin Darby , Péptidos/síntesis química , Relación Estructura-Actividad , Carga Viral/efectos de los fármacos
9.
Nano Lett ; 18(2): 1416-1420, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29385346

RESUMEN

Atomically thin 2D materials span the common components of electronic circuits as metals, semiconductors, and insulators, and can manifest correlated phases such as superconductivity, charge density waves, and magnetism. An ongoing challenge in the field is to incorporate these 2D materials into multilayer heterostructures with robust electrical contacts while preventing disorder and degradation. In particular, preserving and studying air-sensitive 2D materials has presented a significant challenge since they readily oxidize under atmospheric conditions. We report a new technique for contacting 2D materials, in which metal via contacts are integrated into flakes of insulating hexagonal boron nitride, and then placed onto the desired conducting 2D layer, avoiding direct lithographic patterning onto the 2D conductor. The metal contacts are planar with the bottom surface of the boron nitride and form robust contacts to multiple 2D materials. These structures protect air-sensitive 2D materials for months with no degradation in performance. This via contact technique will provide the capability to produce "atomic printed circuit boards" that can form the basis of more complex multilayer heterostructures.

11.
J Cell Biochem ; 119(4): 3697-3705, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29236331

RESUMEN

Neuroendocrine prostate cancer (NE PCa) is an aggressive malignancy, often presenting with advanced metastasis. We previously reported that reduction of histone marks regulated by DNMT1 following epidrug (5-Azacitidine, 5-Aza) treatment controls induction of epithelial to mesenchymal (EMT) and a cancer stem cell (CSC) phenotype, which facilitates tumorigenesis in PCa cells. Here, we use the epidrug 5-Aza as a model for how histone marks may regulate the reprogramming of prostate adenocarcinoma into NE phenotypic cells. First, we observed that 5-Aza treatment of PCa cells in vitro induces a neuron-like phenotype. In addition, significant increases in the expression of the NE markers N-Myc downstream regulated gene 1 (NDRG1), enolase-2 (ENO2), and synaptophysin were observed. Critically, a high density of NE cells with synaptophysin expression was found in tumors generated by 5-Aza pretreatment of PCa cells. Importantly, induction of NE differentiation of PCa cells was associated with an enhancement of NDRG1 expression by reduction of two histone marks, H3K9me3 and H3K27me3. Further, more NDRG1 expression was detected in the subset of PCa cells with reduced expression of H3K9me3 or H3K27me3 in the tumors generated by 5-Aza pretreated PCa cells and critically, these biological differences are also observed in small cell carcinoma in advanced stage of human primary PCa tumors. Our results suggest that reduction of histone marks regulated by the epidrug 5-Aza may control induction of a NE phenotype, which facilitates PCa progression. These studies suggest a strong rationale for developing therapeutics, which target epigenetic regulation.


Asunto(s)
Neoplasias de la Próstata/metabolismo , Western Blotting , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Inmunoprecipitación de Cromatina , Epigénesis Genética/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Neoplasias de la Próstata/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
J Cell Biochem ; 119(10): 8074-8083, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29380900

RESUMEN

Therapeutic strategies targeting both cancer cells and associated cells in the tumor microenvironment offer significant promise in cancer therapy. We previously reported that generation 5 (G5) dendrimers conjugated with cyclic-RGD peptides target cells expressing integrin alpha V beta 3. In this study, we report a novel dendrimer conjugate modified to deliver the mammalian target of rapamycin (mTOR) inhibitor, rapamycin. In vitro analyses demonstrated that this drug conjugate, G5-FI-RGD-rapamycin, binds to prostate cancer (PCa) cells and fibroblasts to inhibit mTOR signaling and VEGF expression. In addition, G5-FI-RGD-rapamycin inhibits mTOR signaling in cancer cells more efficiently under proinflammatory conditions compared to free rapamycin. In vivo studies established that G5-FI-RGD-rapamycin significantly inhibits fibroblast-mediated PCa progression and metastasis. Thus, our results suggest the potential of new rapamycin-conjugated multifunctional nanoparticles for PCa therapy.


Asunto(s)
Dendrímeros/química , Integrina alfaVbeta3/metabolismo , Metástasis de la Neoplasia/tratamiento farmacológico , Péptidos Cíclicos/química , Neoplasias de la Próstata/tratamiento farmacológico , Sirolimus/química , Sirolimus/uso terapéutico , Animales , Western Blotting , Línea Celular Tumoral , Células Cultivadas , Fibroblastos , Citometría de Flujo , Humanos , Masculino , Ratones , Células PC-3
13.
J Cell Biochem ; 118(4): 891-902, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27753136

RESUMEN

Many prostate cancer (PCa) recurrences are thought to be due to reactivation of disseminated tumor cells (DTCs). We previously found a role of the TAM family of receptor tyrosine kinases TYRO3, AXL, and MERTK in PCa dormancy regulation. However, the mechanism and contributions of the individual TAM receptors is largely unknown. Knockdown of MERTK, but not AXL or TYRO3 by shRNA in PCa cells induced a decreased ratio of P-Erk1/2 to P-p38, increased expression of p27, NR2F1, SOX2, and NANOG, induced higher levels of histone H3K9me3 and H3K27me3, and induced a G1/G0 arrest, all of which are associated with dormancy. Similar effects were also observed with siRNA. Most importantly, knockdown of MERTK in PCa cells increased metastasis free survival in an intra-cardiac injection mouse xenograft model. MERTK knockdown also failed to inhibit PCa growth in vitro and subcutaneous growth in vivo, which suggests that MERTK has specificity for dormancy regulation or requires a signal from the PCa microenvironment. The effects of MERTK on the cell cycle and histone methylation were reversed by p38 inhibitor SB203580, which indicates the importance of MAP kinases for MERTK dormancy regulation. Overall, this study shows that MERTK stimulates PCa dormancy escape through a MAP kinase dependent mechanism, also involving p27, pluripotency transcription factors, and histone methylation. J. Cell. Biochem. 118: 891-902, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Ciclo Celular , Línea Celular Tumoral , Supervivencia Celular , Técnicas de Silenciamiento del Gen , Xenoinjertos , Histonas/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas , Masculino , Ratones , Ratones SCID , Recurrencia Local de Neoplasia/enzimología , Recurrencia Local de Neoplasia/patología , Neoplasias de la Próstata/secundario , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Escape del Tumor , Microambiente Tumoral , Tirosina Quinasa c-Mer
14.
Biochem Biophys Res Commun ; 488(1): 53-59, 2017 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-28476622

RESUMEN

Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins mediate intracellular membrane fusion by forming a ternary SNARE complex. A minimalist approach utilizing proteoliposomes with reconstituted SNARE proteins yielded a wealth of information pinpointing the molecular mechanism of SNARE-mediated fusion and its regulation by accessory proteins. Two important attributes of a membrane fusion are lipid-mixing and the formation of an aqueous passage between apposing membranes. These two attributes are typically observed by using various fluorescent dyes. Currently available in vitro assay systems for observing fusion pore opening have several weaknesses such as cargo-bleeding, incomplete removal of unencapsulated dyes, and inadequate information regarding the size of the fusion pore, limiting measurements of the final stage of membrane fusion. In the present study, we used a biotinylated green fluorescence protein and streptavidin conjugated with Dylight 594 (DyStrp) as a Föster resonance energy transfer (FRET) donor and acceptor, respectively. This FRET pair encapsulated in each v-vesicle containing synaptobrevin and t-vesicle containing a binary acceptor complex of syntaxin 1a and synaptosomal-associated protein 25 revealed the opening of a large fusion pore of more than 5 nm, without the unwanted signals from unencapsulated dyes or leakage. This system enabled determination of the stoichiometry of the merging vesicles because the FRET efficiency of the FRET pair depended on the molar ratio between dyes. Here, we report a robust and informative assay for SNARE-mediated fusion pore opening.


Asunto(s)
Proteínas Fluorescentes Verdes/metabolismo , Proteínas SNARE/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Proteínas Fluorescentes Verdes/química , Fusión de Membrana , Compuestos Orgánicos/química , Compuestos Orgánicos/metabolismo , Estreptavidina/química , Estreptavidina/metabolismo
15.
J Cell Biochem ; 117(12): 2815-2824, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27153245

RESUMEN

Prostate cancer (PCa) is known to develop resistance to chemotherapy. Growth arrest-specific 6 (GAS6), plays a role in tumor progression by regulating growth in many cancers. Here, we explored how GAS6 regulates the cell cycle and apoptosis of PCa cells in response to chemotherapy. We found that GAS6 is sufficient to significantly increase the fraction of cells in G1 and the duration of phase in PCa cells. Importantly, the effect of GAS6 on G1 is potentiated during docetaxel chemotherapy. GAS6 altered the levels of several key cell cycle regulators, including the downregulation of Cyclin B1 (G2 /M phase), CDC25A, Cyclin E1, and CDK2 (S phase entry), while the upregulation of cell cycle inhibitors p27 and p21, Cyclin D1, and CDK4. Importantly, these changes became further accentuated during docetaxel treatment in the presence of GAS6. Moreover, GAS6 alters the apoptotic response of PCa cells during docetaxel chemotherapy. Docetaxel induced PCa cell apoptosis is efficiently suppressed in PCa cell culture in the presence of GAS6 or GAS6 secreted from co-cultured osteoblasts. Similarly, the GAS6-expressing bone environment protects PCa cells from apoptosis within primary tumors in vivo studies. Docetaxel induced significant levels of Caspase-3 and PARP cleavage in PCa cells, while GAS6 protected PCa cells from docetaxel-induced apoptotic signaling. Together, these data suggest that GAS6, expressed by osteoblasts in the bone marrow, plays a significant role in the regulation of PCa cell survival during chemotherapy, which will have important implications for targeting metastatic disease. J. Cell. Biochem. 117: 2815-2824, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Apoptosis/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Fase G1/efectos de los fármacos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/fisiología , Neoplasias de la Próstata/patología , Fase S/efectos de los fármacos , Animales , Antineoplásicos/farmacología , Western Blotting , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Docetaxel , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Masculino , Ratones , Ratones Noqueados , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Taxoides/farmacología
16.
J Clin Periodontol ; 43(8): 659-67, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27062507

RESUMEN

AIM: This study was conducted to determine periodontal changes in postmenopausal breast cancer (BCa) survivors using aromatase inhibitors (AI) as compared to postmenopausal women without BCa. METHODS: An 18-month prospective examination of periodontal health in postmenopausal women (29 receiving AI therapy; 29 women without BCa) was conducted at University of Michigan. Comprehensive periodontal examinations including alveolar bone height (ABH) were conducted at baseline, 6, 12, and 18 months. Bisphosphonate, vitamin D, and calcium supplementation were collected via chart review. Linear mixed models were utilized to investigate the relationship between AI and periodontal measures. RESULTS: Aromatase inhibitor users had significantly deeper probing depths, more dental plaque and clinical attachment loss as compared to controls at the 6, 12, and 18 month study visits (p < 0.05). ABH loss was seen over time within the AI group. The linear mixed model showed a significant effect of time as well as an interaction between aromatase inhibitor use and calcium supplement status. AI users taking calcium experienced less ABH loss over the study than AI users not taking calcium (p = 0.005). CONCLUSION: Aromatase inhibitor therapy has a negative impact on the periodontal health of postmenopausal BCa patients. Calcium supplementation appears to mitigate ABH loss in women on AI.


Asunto(s)
Neoplasias de la Mama , Inhibidores de la Aromatasa , Densidad Ósea , Femenino , Humanos , Posmenopausia , Estudios Prospectivos , Vitamina D
17.
Biochem Biophys Res Commun ; 465(4): 864-70, 2015 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-26319432

RESUMEN

Soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (SNARE) proteins generate energy required for membrane fusion. They form a parallelly aligned four-helix bundle called the SNARE complex, whose formation is initiated from the N terminus and proceeds toward the membrane-proximal C terminus. Previously, we have shown that this zippering-like process can be controlled by several flavonoids that bind to the intermediate structures formed during the SNARE zippering. Here, our aim was to test whether the fluorescence resonance energy transfer signals that are observed during the inner leaflet mixing assay indeed represent the hemifused vesicles. We show that changes in vesicle size accompanying the merging of bilayers is a good measure of progression of the membrane fusion. Two merging vesicles with the same size D in diameter exhibited their hydrodynamic diameters 2D + d (d, intermembrane distance), 2D and 2D as membrane fusion progressed from vesicle docking to hemifusion and full fusion, respectively. A dynamic light scattering assay of membrane fusion suggested that myricetin stopped membrane fusion at the hemifusion state, whereas delphinidin and cyanidin prevented the docking of the vesicles. These results are consistent with our previous findings in fluorescence resonance energy transfer assays.


Asunto(s)
Flavonoides/metabolismo , Fusión de Membrana/fisiología , Proteínas SNARE/química , Proteínas SNARE/metabolismo , Animales , Dispersión Dinámica de Luz , Flavonoides/farmacología , Transferencia Resonante de Energía de Fluorescencia , Hidrodinámica , Membrana Dobles de Lípidos/metabolismo , Fusión de Membrana/efectos de los fármacos , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Unión Proteica , Ratas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
18.
Opt Express ; 23(22): 28300-5, 2015 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-26561101

RESUMEN

ß-Ga(2)O(3) films grown on Al(2)O(3) by a metalorganic chemical vapor deposition technique were used to fabricate a solar-blind photodetector with a planar photoconductor structure. The crystal structure and quality of the ß-Ga(2)O(3) films were analyzed using X-ray diffraction and micro-Raman spectroscopy. Si ions were introduced into the ß-Ga(2)O(3) thin films by ion implantation method and activated by an annealing process to form an Ohmic contact between the Ti/Au electrode and the ß-Ga(2)O(3) film. The electrical conductivity of the ß-Ga(2)O(3) films was greatly improved by the implantation and subsequent activation of the Si ions. The photoresponse properties of the photodetectors were investigated by analyzing the current-voltage characteristics and the time-dependent photoresponse curves. The fabricated solar-blind photodetectors exhibited photoresponse to 254 nm wavelength, and blindness to 365 nm light, with a high spectral selectivity.

19.
Biochem Biophys Res Commun ; 450(1): 831-6, 2014 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-24960195

RESUMEN

Fusion of synaptic vesicles with the presynaptic plasma membrane in the neuron is mediated by soluble N-ethylmaleimide-sensitive fusion protein-attachment protein receptor (SNARE) proteins. SNARE complex formation is a zippering-like process which initiates at the N-terminus and proceeds to the C-terminal membrane-proximal region. Previously, we showed that this zippering-like process is regulated by several polyphenols, leading to the arrest of membrane fusion and the inhibition of neuroexocytosis. In vitro studies using purified SNARE proteins reconstituted in liposomes revealed that each polyphenol uniquely regulates SNARE zippering. However, the unique regulatory effect of each polyphenol in cells has not yet been examined. In the present study, we observed SNARE zippering in neuronal PC12 cells by measuring the fluorescence resonance energy transfer (FRET) changes of a cyan fluorescence protein (CFP) and a yellow fluorescence protein (YFP) fused to the N-termini or C-termini of SNARE proteins. We show that delphinidin and cyanidin inhibit the initial N-terminal nucleation of SNARE complex formation in a Ca(2+)-independent manner, while myricetin inhibits Ca(2+)-dependent transmembrane domain association of the SNARE complex in the cell. This result explains how polyphenols exhibit botulinum neurotoxin-like activity in vivo.


Asunto(s)
Calcio/metabolismo , Membrana Celular/metabolismo , Leucina Zippers/efectos de los fármacos , Fusión de Membrana/fisiología , Neuronas/metabolismo , Polifenoles/farmacología , Proteínas SNARE/metabolismo , Animales , Membrana Celular/efectos de los fármacos , Fusión de Membrana/efectos de los fármacos , Neuronas/efectos de los fármacos , Células PC12 , Ratas
20.
Opt Express ; 22 Suppl 3: A986-91, 2014 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-24922404

RESUMEN

We investigated the morphological, structural and optical properties of CdCl2-treated cadmium telluride (CdTe) thin films deposited on defective graphene using a close-spaced sublimation (CSS) system. Heat treatment in the presence of CdCl2 caused recrystallization of CSS-grown CdTe over the as-deposited structures. The preferential (111) orientation of as-deposited CdTe films was randomized after post-growth CdCl2 treatment. New small grains (bumps) on the surface of CdCl2-treated CdTe films were ascribed to nucleation of the CdTe grains during the CdCl2 treatment. The properties of as-deposited and CdCl2-treated CdTe films were characterized by room temperature micro-photoluminescence, micro-Raman spectroscopy, scanning electron microscopy, and X-ray diffraction analysis. Our results are useful to demonstrate a substrate configuration CdTe thin film solar cells.

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