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1.
Appl Opt ; 63(14): 3998-4005, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856364

RESUMEN

795 nm vertical-cavity surface-emitting lasers (VCSELs) with dielectric surface gratings to control the output polarization are designed and fabricated. The calculated results demonstrate that a well-designed S i N x surface grating positioned on the surface of an anti-phase VCSEL structure enhances the reflectivity difference between the two polarization modes compared to a conventional GaAs surface grating, consequently resulting in a larger gain anisotropy in VCSELs and a high orthogonal polarization suppression ratio (OPSR). Characterization shows that a peak-to-peak OPSR of 30.3 dB is achieved at 85°C for 795 nm VCSELs with a S i N x surface grating of 5 µm in diameter and an oxide aperture of ∼4µm, demonstrating the effectiveness of the S i N x surface grating in polarization control for 795 nm VCSELs.

2.
Opt Express ; 31(9): 14482-14494, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37157312

RESUMEN

In the photovoltaic community, short circuit current (Isc) of a current mismatched multijunction photovoltaic (MJPV) cell was usually thought to be limited by the lowest subcell photocurrent (Imin). However, under certain conditions for multijunction solar cells, Isc≠Imin was observed by researchers, while this effect has not been studied in multijunction laser power converters (MJLPCs). In this work, we provide an in-depth analysis of the formation mechanisms for the Isc of the MJPV cell by measuring I-V curves of the GaAs and InGaAs LPCs with different number of subcells and simulating the I-V curves with the reverse breakdown of each subcell considered. It is found that Isc of an N-junction PV cell can be theoretically equal to any current value within a range from a current lower than Imin to the maximum subcell photocurrent, which is up to the number of subcell current steps in the forward biased I-V curve. An MJPV cell with a constant Imin will demonstrate a higher Isc if it has more subcells, smaller subcell reverse breakdown voltage and smaller series resistance. As a result, Isc tends to be limited by the photocurrent of a subcell closer to the middle cell and is less sensitive to the optical wavelength than Imin. This should be another possible reason why the measured EQE of a multijunction LPC exhibits a wider spectrum width than the calculated Imin-based EQE, whereas this was usually attributed to the luminescent coupling effect merely.

3.
Nanomaterials (Basel) ; 13(6)2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36986014

RESUMEN

Low threshold current and polarization-stabilized 795 nm vertical-cavity surface-emitting lasers (VCSELs) are fabricated by integrating a surface grating of high polarization selectivity and high reflectivity. The rigorous coupled-wave analysis method is used to design the surface grating. For the devices with a grating period of 500 nm, a grating depth of ~150 nm, and a diameter of the surface grating region of 5 µm, a threshold current of 0.4 mA and an orthogonal polarization suppression ratio (OPSR) of 19.56 dB are obtained. The emission wavelength of 795 nm of a single transverse mode VCSEL is achieved at a temperature of 85 °C under an injection current of 0.9 mA. In addition, experiments demonstrate that the threshold and output power also depended on the size of the grating region.

4.
Cancer Med ; 12(1): 584-596, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35676822

RESUMEN

BACKGROUND: Non-small cell lung cancer (NSCLC) comprises the majority (~85%) of all lung tumors, with lung adenocarcinoma (LUAD) and squamous cell carcinoma (LUSC) being the most frequently diagnosed histological subtypes. Multi-modal omics profiling has been carried out in NSCLC, but no studies have yet reported a unique metabolite-related gene signature and altered metabolic pathways associated with LUAD and LUSC. METHODS: We integrated transcriptomics and metabolomics to analyze 30 human lung tumors and adjacent noncancerous tissues. Differential co-expression was used to identify modules of metabolites that were altered between normal and tumor. RESULTS: We identified unique metabolite-related gene signatures specific for LUAD and LUSC and key pathways aberrantly regulated at both transcriptional and metabolic levels. Differential co-expression analysis revealed that loss of coherence between metabolites in tumors is a major characteristic in both LUAD and LUSC. We identified one metabolic onco-module gained in LUAD, characterized by nine metabolites and 57 metabolic genes. Multi-omics integrative analysis revealed a 28 metabolic gene signature associated with poor survival in LUAD, with six metabolite-related genes as individual prognostic markers. CONCLUSIONS: We demonstrated the clinical utility of this integrated metabolic gene signature in LUAD by using it to guide repurposing of AZD-6482, a PI3Kß inhibitor which significantly inhibited three genes from the 28-gene signature. Overall, we have integrated metabolomics and transcriptomics analyses to show that LUAD and LUSC have distinct profiles, inferred gene signatures with prognostic value for patient survival, and identified therapeutic targets and repurposed drugs for potential use in NSCLC treatment.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Transcriptoma , Adenocarcinoma del Pulmón/genética , Perfilación de la Expresión Génica
5.
Appl Opt ; 61(28): 8389-8394, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36256153

RESUMEN

795 nm vertical-cavity surface-emitting lasers (VCSELs) with in-phase surface gratings are fabricated and investigated theoretically and experimentally. The polarization characteristics of 795 nm VCSELs with various grating periods and depths are analyzed using the rigorous coupled-wave analysis (RCWA) method; the dependence of polarization stability on the profile of gratings demonstrates that the trapezoid grating ridge slightly enhances the orthogonal polarization suppression ratio (OPSR), but increases the threshold current. The fabricated VCSELs with a sub-wavelength in-phase surface grating of a duty cycle of 0.5 show stabilized output polarization at the cost of increasing the threshold current which is in agreement with the calculations. The grating VCSELs with a period of 200 nm and an oxide aperture of 3.43µm×4.39µm produce a single-mode output with an OPSR of 16.6 dB and a slope efficiency of 0.42 W/A at 85°C.

6.
Endocr Relat Cancer ; 29(1): 15-31, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34636746

RESUMEN

Castration-resistant prostate cancer (CRPC) remains highly lethal and in need of novel, actionable therapeutic targets. The pioneer factor GATA2 is a significant prostate cancer (PC) driver and is linked to poor prognosis. GATA2 directly promotes androgen receptor (AR) gene expression (both full-length and splice-variant) and facilitates AR binding to chromatin, recruitment of coregulators, and target gene transcription. Unfortunately, there is no clinically applicable GATA2 inhibitor available at the moment. Using a bioinformatics algorithm, we screened in silico 2650 clinically relevant drugs for a potential GATA2 inhibitor. Validation studies used cytotoxicity and proliferation assays, global gene expression analysis, RT-qPCR, reporter assay, reverse phase protein array analysis (RPPA), and immunoblotting. We examined target engagement via cellular thermal shift assay (CETSA), ChIP-qPCR, and GATA2 DNA-binding assay. We identified the vasodilator dilazep as a potential GATA2 inhibitor and confirmed on-target activity via CETSA. Dilazep exerted anticancer activity across a broad panel of GATA2-dependent PC cell lines in vitro and in a PDX model in vivo. Dilazep inhibited GATA2 recruitment to chromatin and suppressed the cell-cycle program, transcriptional programs driven by GATA2, AR, and c-MYC, and the expression of several oncogenic drivers, including AR, c-MYC, FOXM1, CENPF, EZH2, UBE2C, and RRM2, as well as of several mediators of metastasis, DNA damage repair, and stemness. In conclusion, we provide, via an extensive compendium of methodologies, proof-of-principle that a small molecule can inhibit GATA2 function and suppress its downstream AR, c-MYC, and other PC-driving effectors. We propose GATA2 as a therapeutic target in CRPC.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Línea Celular Tumoral , Cromatina , Dilazep/uso terapéutico , Factor de Transcripción GATA2/genética , Factor de Transcripción GATA2/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Oncogenes , Neoplasias de la Próstata Resistentes a la Castración/genética , Receptores Androgénicos/metabolismo
8.
Sci Rep ; 11(1): 1393, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33446905

RESUMEN

Prostate cancer (PCa) is dependent on the androgen receptor (AR). Advanced PCa is treated with an androgen deprivation therapy-based regimen; tumors develop resistance, although they typically remain AR-dependent. Expression of constitutively active AR variants lacking the ligand-binding domain including the variant AR-V7 contributes to this resistance. AR and AR-V7, as transcription factors, regulate many of the same genes, but also have unique activities. In this study, the capacity of the two AR isoforms to regulate splicing was examined. RNA-seq data from models that endogenously express AR and express AR-V7 in response to doxycycline were used. Both AR isoforms induced multiple changes in splicing and many changes were isoform-specific. Analyses of two endogenous genes, PGAP2 and TPD52, were performed to examine differential splicing. A novel exon that appears to be a novel transcription start site was preferentially induced by AR-V7 in PGAP2 although it is induced to a lesser extent by AR. The previously described AR induced promoter 2 usage that results in a novel protein derived from TPD52 (PrLZ) was not induced by AR-V7. AR, but not AR-V7, bound to a site proximal to promoter 2, and induction was found to depend on FOXA1.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Proteínas de Neoplasias/biosíntesis , Neoplasias de la Próstata/metabolismo , Empalme del ARN , Receptores Androgénicos/biosíntesis , Línea Celular Tumoral , Humanos , Masculino , Proteínas de Neoplasias/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , RNA-Seq , Receptores Androgénicos/genética
9.
RSC Adv ; 11(51): 32419-32424, 2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-35495503

RESUMEN

The development of highly gas-permeable membranes is required for gas separation applications. In this study, 1-(p-trimethylsilyl)phenyl-1-propyne (SPP) was copolymerized with diphenylacetylenes bearing tert-butyl (BDPA) and SiMe3 (SDPA) groups at various feed ratios to obtain poly(SPP-co-BDPA) and poly(SPP-co-SDPA) copolymers, respectively. Free-standing membranes were fabricated from toluene solutions of the copolymers, the gas permeability of which increased as the SPP ratio decreased (P O2 : 550-2100 barrers). Interestingly, poly(SPP-co-BDPA) and poly(SPP-co-SDPA) at a 1 : 4 ratio of SPP:BDPA and SPP:SDPA, respectively, showed higher permeabilities than the respective homopolymers. Desilylation of the poly(SPP-co-BDPA) membrane increased the gas permeability, whereas desilylation of the poly(SPP-co-SDPA) membrane had the opposite result.

10.
Nat Commun ; 11(1): 2316, 2020 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-32385268

RESUMEN

Our early-life environment has a profound influence on developing organs that impacts metabolic function and determines disease susceptibility across the life-course. Using a rat model for exposure to an endocrine disrupting chemical (EDC), we show that early-life chemical exposure causes metabolic dysfunction in adulthood and reprograms histone marks in the developing liver to accelerate acquisition of an adult epigenomic signature. This epigenomic reprogramming persists long after the initial exposure, but many reprogrammed genes remain transcriptionally silent with their impact on metabolism not revealed until a later life exposure to a Western-style diet. Diet-dependent metabolic disruption was largely driven by reprogramming of the Early Growth Response 1 (EGR1) transcriptome and production of metabolites in pathways linked to cholesterol, lipid and one-carbon metabolism. These findings demonstrate the importance of epigenome:environment interactions, which early in life accelerate epigenomic aging, and later in adulthood unlock metabolically restricted epigenetic reprogramming to drive metabolic dysfunction.


Asunto(s)
Epigenoma/genética , Animales , Metilación de ADN/efectos de los fármacos , Metilación de ADN/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Disruptores Endocrinos/toxicidad , Epigénesis Genética/efectos de los fármacos , Epigénesis Genética/genética , Epigenómica/métodos , Femenino , Interacción Gen-Ambiente , Estudio de Asociación del Genoma Completo , Masculino , Ratas
11.
Environ Health Perspect ; 128(1): 17010, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31939706

RESUMEN

BACKGROUND: Tributyltin (TBT) is a persistent and bioaccumulative environmental toxicant. Developmental exposure to TBT has been shown to cause fatty liver disease (steatosis), as well as increased adiposity in many species, leading to its characterization as an obesogen. OBJECTIVE: We aimed to determine the long-term effects of developmental TBT exposure on the liver. METHODS: C57BL/6J mice were exposed to a dose of TBT (0.5mg/kg body weight per day; 3.07µM) below the current developmental no observed adverse effect level (NOAEL) via drinking water, or drinking water alone, provided to the dam from preconception through lactation. Sires were exposed during breeding and lactation. Pups from two parity cycles were included in this study. Animals were followed longitudinally, and livers of offspring were analyzed by pathological evaluation, immunohistochemistry, immunoblotting, and RNA sequencing. RESULTS: Developmental exposure to TBT led to increased adiposity and hepatic steatosis at 14 and 20 weeks of age and increased liver adenomas at 45 weeks of age in male offspring. Female offspring displayed increased adiposity as compared with males, but TBT did not lead to an increase in fatty liver or tumor development in female offspring. Liver tumors in male mice were enriched in pathways and gene signatures associated with human and rodent nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC). This includes down-regulation of growth hormone receptor (GHR) and of STAT5 signaling, which occurred in response to TBT exposure and preceded liver tumor development. CONCLUSIONS: These data reveal a previously unappreciated ability of TBT to increase risk for liver tumorigenesis in mice in a sex-specific manner. Taken together, these findings provide new insights into how early life environmental exposures contribute to liver disease in adulthood. https://doi.org/10.1289/EHP5414.


Asunto(s)
Contaminantes Ambientales/toxicidad , Compuestos Orgánicos de Estaño/toxicidad , Adiposidad , Animales , Humanos , Neoplasias Hepáticas/inducido químicamente , Ratones , Ratones Endogámicos C57BL , Pruebas de Toxicidad
13.
Clin Cancer Res ; 25(12): 3689-3701, 2019 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-30846479

RESUMEN

PURPOSE: The perturbation of metabolic pathways in high-grade bladder cancer has not been investigated. We aimed to identify a metabolic signature in high-grade bladder cancer by integrating unbiased metabolomics, lipidomics, and transcriptomics to predict patient survival and to discover novel therapeutic targets. EXPERIMENTAL DESIGN: We performed high-resolution liquid chromatography mass spectrometry (LC-MS) and bioinformatic analysis to determine the global metabolome and lipidome in high-grade bladder cancer. We further investigated the effects of impaired metabolic pathways using in vitro and in vivo models. RESULTS: We identified 519 differential metabolites and 19 lipids that were differentially expressed between low-grade and high-grade bladder cancer using the NIST MS metabolomics compendium and lipidblast MS/MS libraries, respectively. Pathway analysis revealed a unique set of biochemical pathways that are highly deregulated in high-grade bladder cancer. Integromics analysis identified a molecular gene signature associated with poor patient survival in bladder cancer. Low expression of CPT1B in high-grade tumors was associated with low FAO and low acyl carnitine levels in high-grade bladder cancer, which were confirmed using tissue microarrays. Ectopic expression of the CPT1B in high-grade bladder cancer cells led to reduced EMT in in vitro, and reduced cell proliferation, EMT, and metastasis in vivo. CONCLUSIONS: Our study demonstrates a novel approach for the integration of metabolomics, lipidomics, and transcriptomics data, and identifies a common gene signature associated with poor survival in patients with bladder cancer. Our data also suggest that impairment of FAO due to downregulation of CPT1B plays an important role in the progression toward high-grade bladder cancer and provide potential targets for therapeutic intervention.


Asunto(s)
Carnitina O-Palmitoiltransferasa/metabolismo , Ácidos Grasos/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Biomarcadores de Tumor/metabolismo , Humanos , Lipidómica/métodos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Metaboloma , Clasificación del Tumor , Valor Predictivo de las Pruebas , Tasa de Supervivencia , Transcriptoma , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/patología
14.
Invest Ophthalmol Vis Sci ; 59(1): 132-143, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29332125

RESUMEN

Purpose: Uveal melanoma (UM) is uniformly refractory to all available systemic chemotherapies, thus creating an urgent need for novel therapeutics. In this study, we investigated the sensitivity of UM cells to ICG-001, a small molecule reported to suppress the Wnt/ß-catenin-mediated transcriptional program. Methods: We used a panel of UM cell lines to examine the effects of ICG-001 on cellular proliferation, migration, and gene expression. In vivo efficacy of ICG-001 was evaluated in a UM xenograft model. Results: ICG-001 exerted strong antiproliferative activity against UM cells, leading to cell cycle arrest, apoptosis, and inhibition of migration. Global gene expression profiling revealed strong suppression of genes associated with cell cycle proliferation, DNA replication, and G1/S transition. Gene set enrichment analysis revealed that ICG-001 suppressed Wnt, mTOR, and MAPK signaling. Strikingly, ICG-001 suppressed the expression of genes associated with UM aggressiveness, including CDH1, CITED1, EMP1, EMP3, SDCBP, and SPARC. Notably, the transcriptomic footprint of ICG-001, when applied to a UM patient dataset, was associated with better clinical outcome. Lastly, ICG-001 exerted anticancer activity against a UM tumor xenograft in mice. Conclusions: Using in vitro and in vivo experiments, we demonstrate that ICG-001 has strong anticancer activity against UM cells and suppresses transcriptional programs critical for the cancer cell. Our results suggest that ICG-001 holds promise and should be examined further as a novel therapeutic agent for UM.


Asunto(s)
Apoptosis/efectos de los fármacos , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Genes Relacionados con las Neoplasias/genética , Melanoma/tratamiento farmacológico , Neoplasias Experimentales , Pirimidinonas/farmacología , Neoplasias de la Úvea/tratamiento farmacológico , Animales , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Melanoma/genética , Melanoma/metabolismo , Ratones Desnudos , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/metabolismo
15.
Genome Biol ; 19(1): 2, 2018 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-29310692

RESUMEN

BACKGROUND: Monozygotic twins have long been studied to estimate heritability and explore epigenetic influences on phenotypic variation. The phenotypic and epigenetic similarities of monozygotic twins have been assumed to be largely due to their genetic identity. RESULTS: Here, by analyzing data from a genome-scale study of DNA methylation in monozygotic and dizygotic twins, we identified genomic regions at which the epigenetic similarity of monozygotic twins is substantially greater than can be explained by their genetic identity. This "epigenetic supersimilarity" apparently results from locus-specific establishment of epigenotype prior to embryo cleavage during twinning. Epigenetically supersimilar loci exhibit systemic interindividual epigenetic variation and plasticity to periconceptional environment and are enriched in sub-telomeric regions. In case-control studies nested in a prospective cohort, blood DNA methylation at these loci years before diagnosis is associated with risk of developing several types of cancer. CONCLUSIONS: These results establish a link between early embryonic epigenetic development and adult disease. More broadly, epigenetic supersimilarity is a previously unrecognized phenomenon that may contribute to the phenotypic similarity of monozygotic twins.


Asunto(s)
Epigénesis Genética , Gemelos Monocigóticos/genética , Islas de CpG , ADN/sangre , Metilación de ADN , Genoma Humano , Humanos , Modelos Genéticos , Neoplasias/genética , Gemelos Dicigóticos
16.
Eur Urol Focus ; 4(6): 907-915, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-28753886

RESUMEN

BACKGROUND: The first global lipidomic profiles associated with urothelial cancer of the bladder (UCB) and its clinical stages associated with progression were identified. OBJECTIVE: To identify lipidomic signatures associated with survival and different clinical stages of UCB. DESIGN, SETTING, AND PARTICIPANTS: Pathologically confirmed 165 bladder-derived tissues (126 UCB, 39 benign adjacent or normal bladder tissues). UCB tissues included Ta (n=16), T1 (n=30), T2 (n=43), T3 (n=27), and T4 (n=9); lymphovascular invasion (LVI) positive (n=52) and negative (n=69); and lymph node status N0 (n=28), N1 (n=11), N2 (n=9), N3 (n=3), and Nx (n=75). RESULTS AND LIMITATIONS: UCB tissues have higher levels of phospholipids and fatty acids, and reduced levels of triglycerides compared with benign tissues. A total of 59 genes associated with altered lipids in UCB strongly correlate with patient survival in an UCB public dataset. Within UCB, there was a progressive decrease in the levels of phosphatidylserine (PS), phosphatidylethanolamines (PEs), and phosphocholines, whereas an increase in the levels of diacylglycerols (DGs) with tumor stage. Transcript and protein expression of phosphatidylserine synthase 1, which converts DGs to PSs, decreased progressively with tumor stage. Levels of DGs and lyso-PEs were significantly elevated in tumors with LVI and lymph node involvement, respectively. Lack of carcinoma in situ and treatment information is the limitation of our study. CONCLUSIONS: To date, this is the first study describing the global lipidomic profiles associated with UCB and identifies lipids associated with tumor stages, LVI, and lymph node status. Our data suggest that triglycerides serve as the primary energy source in UCB, while phospholipid alterations could affect membrane structure and/or signaling associated with tumor progression. PATIENT SUMMARY: Lipidomic alterations identified in this study set the stage for characterization of pathways associated with these altered lipids that, in turn, could inform the development of first-of-its-kind lipid-based noninvasive biomarkers and novel therapeutic targets for aggressive urothelial cancer of the bladder.


Asunto(s)
Carcinoma de Células Transicionales/metabolismo , Ácidos Grasos/metabolismo , Fosfolípidos/metabolismo , Triglicéridos/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Carcinoma de Células Transicionales/genética , Carcinoma de Células Transicionales/patología , Estudios de Casos y Controles , Cromatografía Liquida , Biología Computacional , Diglicéridos/metabolismo , Femenino , Humanos , Metabolismo de los Lípidos/genética , Ganglios Linfáticos/patología , Lisofosfolípidos/metabolismo , Masculino , Espectrometría de Masas , Invasividad Neoplásica , Estadificación de Neoplasias , Transferasas de Grupos Nitrogenados/genética , Transferasas de Grupos Nitrogenados/metabolismo , Fosfatidiletanolaminas/metabolismo , Fosfatidilserinas/metabolismo , Fosforilcolina/metabolismo , Análisis de Componente Principal , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología
17.
JCI Insight ; 2(17)2017 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-28878117

RESUMEN

Heart disease remains the leading cause of death worldwide, highlighting a pressing need to identify novel regulators of cardiomyocyte (CM) function that could be therapeutically targeted. The mammalian Hippo/Tead pathway is critical in embryonic cardiac development and perinatal CM proliferation. However, the requirement of Tead1, the transcriptional effector of this pathway, in the adult heart is unknown. Here, we show that tamoxifen-inducible adult CM-specific Tead1 ablation led to lethal acute-onset dilated cardiomyopathy, associated with impairment in excitation-contraction coupling. Mechanistically, we demonstrate Tead1 is a cell-autonomous, direct transcriptional activator of SERCA2a and SR-associated protein phosphatase 1 regulatory subunit, Inhibitor-1 (I-1). Thus, Tead1 deletion led to a decrease in SERCA2a and I-1 transcripts and protein, with a consequent increase in PP1-activity, resulting in accumulation of dephosphorylated phospholamban (Pln) and decreased SERCA2a activity. Global transcriptomal analysis in Tead1-deleted hearts revealed significant changes in mitochondrial and sarcomere-related pathways. Additional studies demonstrated there was a trend for correlation between protein levels of TEAD1 and I-1, and phosphorylation of PLN, in human nonfailing and failing hearts. Furthermore, TEAD1 activity was required to maintain PLN phosphorylation and expression of SERCA2a and I-1 in human induced pluripotent stem cell-derived (iPS-derived) CMs. To our knowledge, taken together, this demonstrates a nonredundant, novel role of Tead1 in maintaining normal adult heart function.


Asunto(s)
Cardiomiopatía Dilatada/metabolismo , Proteínas de Unión al ADN/fisiología , Miocitos Cardíacos/citología , Factores de Transcripción/fisiología , Animales , Proteínas de Unión al Calcio/metabolismo , Cardiomiopatía Dilatada/inducido químicamente , Cardiomiopatía Dilatada/patología , Proliferación Celular , Proteínas de Unión al ADN/genética , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Ratones , Ratones Noqueados , Miocardio/enzimología , Miocardio/metabolismo , Fosforilación , Proteína Fosfatasa 1/metabolismo , Retículo Sarcoplasmático/enzimología , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Factores de Transcripción de Dominio TEA , Tamoxifeno/farmacología , Factores de Transcripción/genética
18.
Mol Cancer Res ; 15(8): 1017-1028, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28507054

RESUMEN

Despite the known importance of androgen receptor (AR) signaling in prostate cancer, the processes downstream of AR that drive disease development and progression remain poorly understood. This knowledge gap has thus limited the ability to treat cancer. Here, it is demonstrated that androgens increase the metabolism of glutamine in prostate cancer cells. This metabolism was required for maximal cell growth under conditions of serum starvation. Mechanistically, AR signaling promoted glutamine metabolism by increasing the expression of the glutamine transporters SLC1A4 and SLC1A5, genes commonly overexpressed in prostate cancer. Correspondingly, gene expression signatures of AR activity correlated with SLC1A4 and SLC1A5 mRNA levels in clinical cohorts. Interestingly, MYC, a canonical oncogene in prostate cancer and previously described master regulator of glutamine metabolism, was only a context-dependent regulator of SLC1A4 and SLC1A5 levels, being unable to regulate either transporter in PTEN wild-type cells. In contrast, rapamycin was able to decrease the androgen-mediated expression of SLC1A4 and SLC1A5 independent of PTEN status, indicating that mTOR complex 1 (mTORC1) was needed for maximal AR-mediated glutamine uptake and prostate cancer cell growth. Taken together, these data indicate that three well-established oncogenic drivers (AR, MYC, and mTOR) function by converging to collectively increase the expression of glutamine transporters, thereby promoting glutamine uptake and subsequent prostate cancer cell growth.Implications: AR, MYC, and mTOR converge to increase glutamine uptake and metabolism in prostate cancer through increasing the levels of glutamine transporters. Mol Cancer Res; 15(8); 1017-28. ©2017 AACR.


Asunto(s)
Sistema de Transporte de Aminoácidos ASC/genética , Antígenos de Histocompatibilidad Menor/genética , Neoplasias de la Próstata/genética , Factores de Transcripción/genética , Carcinogénesis/genética , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Conjuntos de Datos como Asunto , Regulación Neoplásica de la Expresión Génica , Glutamina/genética , Glutamina/metabolismo , Humanos , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Fosfohidrolasa PTEN/genética , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-myc/genética , Transducción de Señal/genética , Serina-Treonina Quinasas TOR/genética
19.
Sci Rep ; 6: 38044, 2016 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-27901079

RESUMEN

A six-volt vertically-stacked, high current GaAs photovoltaic power converter (PPC) has been designed and fabricated to produce output power over 1 W under monochromatic illumination. An N++-GaAs/P++-AlGaAs tunnel junctions (TJs) structure has been used for connecting each sub-cell in this vertically-stacked PPC device. The thickness of the each GaAs sub-cell has been derived based on the calculation of absorption depth of photons with a wavelength of 808 nm using absorption coefficient obtained from ellipsometry measurements. The devices were characterized under non-uniform CW laser illumination at 808 nm with incident power up to 4.1 W. A maximum conversion efficiency of 50.2% was achieved at 0.3 W under non-uniform (coupled in optical fiber) monochromatic illumination, dropping to 42.5% at 4.1 W. The operating voltage at the maximum power point is 5.5-6.0 V, depending on the incident laser power, and an output electrical power output of 1.3 W can be extracted at a laser power of 2.9 W and the maximum electrical power output amounts to 1.72 W. The external quantum efficiency (EQE) measurement indicates that the performance of PPC can be further improved by refining the design of the thickness of sub-cells and improving TJs.

20.
Mol Endocrinol ; 30(8): 937-48, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27409825

RESUMEN

The pregnane X receptor (PXR) (PXR/NR1I3) and constitutive androstane receptor (CAR) (CAR/NR1I2) members of the nuclear receptor (NR) superfamily of ligand-regulated transcription factors are well-characterized mediators of xenobiotic and endocrine-disrupting chemical signaling. The Nuclear Receptor Signaling Atlas maintains a growing library of transcriptomic datasets involving perturbations of NR signaling pathways, many of which involve perturbations relevant to PXR and CAR xenobiotic signaling. Here, we generated a reference transcriptome based on the frequency of differential expression of genes across 159 experiments compiled from 22 datasets involving perturbations of CAR and PXR signaling pathways. In addition to the anticipated overrepresentation in the reference transcriptome of genes encoding components of the xenobiotic stress response, the ranking of genes involved in carbohydrate metabolism and gonadotropin action sheds mechanistic light on the suspected role of xenobiotics in metabolic syndrome and reproductive disorders. Gene Set Enrichment Analysis showed that although acetaminophen, chlorpromazine, and phenobarbital impacted many similar gene sets, differences in direction of regulation were evident in a variety of processes. Strikingly, gene sets representing genes linked to Parkinson's, Huntington's, and Alzheimer's diseases were enriched in all 3 transcriptomes. The reference xenobiotic transcriptome will be supplemented with additional future datasets to provide the community with a continually updated reference transcriptomic dataset for CAR- and PXR-mediated xenobiotic signaling. Our study demonstrates how aggregating and annotating transcriptomic datasets, and making them available for routine data mining, facilitates research into the mechanisms by which xenobiotics and endocrine-disrupting chemicals subvert conventional NR signaling modalities.


Asunto(s)
Receptores Citoplasmáticos y Nucleares/genética , Receptores de Esteroides/genética , Transcriptoma/genética , Animales , Receptor de Androstano Constitutivo , Minería de Datos , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Humanos , Receptor X de Pregnano , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Factores de Transcripción/genética , Xenobióticos/farmacología
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