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1.
Cancer Immunol Immunother ; 72(7): 2283-2297, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36881132

RESUMO

The CD39-CD73-adenosinergic pathway converts adenosine triphosphate (ATP) to adenosine for inhibiting anti-tumor immune responses. Therefore, targeting CD73 to reinvigorate anti-tumor immunity is considered the novel cancer immunotherapy to eradicate tumor cells. To fully understand the critical role of CD39/CD73 in colon adenocarcinoma (COAD), this study aims to comprehensive investigate the prognostic significance of CD39 and CD73 in stage I-IV COAD. Our data demonstrated that CD73 staining strongly marked malignant epithelial cells and CD39 was highly expressed in stromal cells. Attractively, tumor CD73 expression was significantly associated with tumor stage and the risk of distant metastasis, which suggested CD73 was as an independent factor for colon adenocarcinoma patients in univariate COX analysis [HR = 1.465, 95%CI = 1.084-1.978, p = 0.013]; however, high stromal CD39 in COAD patients was more likely to have favorable survival outcome [HR = 1.458, p = 1.103-1.927, p = 0.008]. Notably, high CD73 expression in COAD patients showed poor response to adjuvant chemotherapy and high risk of distant metastasis. High CD73 expression was inversely associated with less infiltration of CD45+ and CD8+ immune cells. However, administration with anti-CD73 antibodies significantly increased the response to oxaliplatin (OXP). Blockade of CD73 signaling synergistically enhanced OXP-induced ATP release, which is a marker of immunogenic cell death (ICD), promotes dendritic cell maturation and immune cell infiltration. Moreover, the risk of colorectal cancer lung metastasis was also decreased. Taken together, the present study revealed tumor CD73 expression inhibited the recruitment of immune cells and correlated with a poor prognosis in COAD patients, especially patients received adjuvant chemotherapy. Targeting CD73 to markedly increased the therapeutic response to chemotherapy and inhibited lung metastasis. Therefore, tumor CD73 may be an independent prognostic factor as well as the potential of therapeutic target for immunotherapy to benefit colon adenocarcinoma patients.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Neoplasias Pulmonares , Humanos , Adenocarcinoma/patologia , Neoplasias do Colo/tratamento farmacológico , Trifosfato de Adenosina/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Oxaliplatina/uso terapêutico , Células Dendríticas/metabolismo
2.
Cancer Cell Int ; 23(1): 49, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932402

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is characterized by an unfavorable prognosis for patients affected. During standard-of-care chemotherapy using temozolomide (TMZ), tumors acquire resistance thereby causing tumor recurrence. Thus, deciphering essential molecular pathways causing TMZ resistance are of high therapeutic relevance. METHODS: Mass spectrometry based proteomics were used to study the GBM proteome. Immunohistochemistry staining of human GBM tissue for either calpain-1 or -2 was performed to locate expression of proteases. In vitro cell based assays were used to measure cell viability and survival of primary patient-derived GBM cells and established GBM cell lines after TMZ ± calpain inhibitor administration. shRNA expression knockdowns of either calpain-1 or calpain-2 were generated to study TMZ sensitivity of the specific subunits. The Comet assay and É£H2AX signal measurements were performed in order to assess the DNA damage amount and recognition. Finally, quantitative real-time PCR of target proteins was applied to differentiate between transcriptional and post-translational regulation. RESULTS: Calcium-dependent calpain proteases, in particular calpain-2, are more abundant in glioblastoma compared to normal brain and increased in patient-matched initial and recurrent glioblastomas. On the cellular level, pharmacological calpain inhibition increased the sensitivities of primary glioblastoma cells towards TMZ. A genetic knockdown of calpain-2 in U251 cells led to increased caspase-3 cleavage and sensitivity to neocarzinostatin, which rapidly induces DNA strand breakage. We hypothesize that calpain-2 causes desensitization of tumor cells against TMZ by preventing strong DNA damage and subsequent apoptosis via post-translational TP53 inhibition. Indeed, proteomic comparison of U251 control vs. U251 calpain-2 knockdown cells highlights perturbed levels of numerous proteins involved in DNA damage response and downstream pathways affecting TP53 and NF-κB signaling. TP53 showed increased protein abundance, but no transcriptional regulation. CONCLUSION: TMZ-induced cell death in the presence of calpain-2 expression appears to favor DNA repair and promote cell survival. We conclude from our experiments that calpain-2 expression represents a proteomic mode that is associated with higher resistance via "priming" GBM cells to TMZ chemotherapy. Thus, calpain-2 could serve as a prognostic factor for GBM outcome.

3.
Mol Cell ; 56(5): 630-40, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25454947

RESUMO

Proteolysis by aspartyl intramembrane proteases such as presenilin and signal peptide peptidase (SPP) underlies many cellular processes in health and disease. Saccharomyces cerevisiae encodes a homolog that we named yeast presenilin fold 1 (Ypf1), which we verify to be an SPP-type protease that localizes to the endoplasmic reticulum (ER). Our work shows that Ypf1 functionally interacts with the ER-associated degradation (ERAD) factors Dfm1 and Doa10 to regulate the abundance of nutrient transporters by degradation. We demonstrate how this noncanonical branch of the ERAD pathway, which we termed "ERAD regulatory" (ERAD-R), responds to ligand-mediated sensing as a trigger. More generally, we show that Ypf1-mediated posttranslational regulation of plasma membrane transporters is indispensible for early sensing and adaptation to nutrient depletion. The combination of systematic analysis alongside mechanistic details uncovers a broad role of intramembrane proteolysis in regulating secretome dynamics.


Assuntos
Retículo Endoplasmático/metabolismo , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Membrana Celular/metabolismo , Degradação Associada com o Retículo Endoplasmático , Regulação Fúngica da Expressão Gênica , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Filogenia , Saccharomyces cerevisiae/fisiologia , Alinhamento de Sequência , Ubiquitina-Proteína Ligases/metabolismo , Zinco/metabolismo
4.
EMBO J ; 33(21): 2492-506, 2014 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-25239945

RESUMO

Signal peptide peptidase (SPP) catalyzes intramembrane proteolysis of signal peptides at the endoplasmic reticulum (ER), but has also been suggested to play a role in ER-associated degradation (ERAD). Here, we show that SPP forms a complex with the ERAD factor Derlin1 and the E3 ubiquitin ligase TRC8 to cleave the unfolded protein response (UPR) regulator XBP1u. Cleavage occurs within a so far unrecognized type II transmembrane domain, which renders XBP1u as an SPP substrate through specific sequence features. Additionally, Derlin1 acts in the complex as a substrate receptor by recognizing the luminal tail of XBP1u. Remarkably, this interaction of Derlin1 with XBP1u obviates the need for ectodomain shedding prior to SPP cleavage, commonly required for intramembrane cuts. Furthermore, we show that XBP1u inhibits the UPR transcription factor XBP1s by targeting it toward proteasomal degradation. Thus, we identify an ERAD complex that controls the abundance of XBP1u and thereby tunes signaling through the UPR.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Degradação Associada com o Retículo Endoplasmático/fisiologia , Proteínas de Membrana/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Serina Endopeptidases/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/genética , Células HEK293 , Humanos , Proteínas de Membrana/genética , Complexo de Endopeptidases do Proteassoma/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Fatores de Transcrição de Fator Regulador X , Serina Endopeptidases/genética , Fatores de Transcrição/genética , Proteína 1 de Ligação a X-Box
5.
Opt Express ; 22(3): 2761-9, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663567

RESUMO

A 10-Gbps optical worldwide interoperability for microwave access (WiMAX) transport system employing vertical cavity surface emitting laser (VCSEL) and spatial light modulator (SLM) with 16-quadrature amplitude modulation (QAM)-orthogonal frequency-division multiplexing (OFDM) modulating signal is proposed. With the assistance of equalizer and low noise amplifier (LNA) at the receiving site, good bit error rate (BER) performance, clear constellation map, and clear eye diagram are achieved in the proposed systems. An optical WiMAX transport system, transmitting 16-QAM-OFDM signal over a 6-m free-space link, with a data rate of 10 Gbps is successfully demonstrated. Such a 10-Gbps optical WiMAX transport system would be attractive for providing services including Internet and telecommunication services. Our proposed system is suitable for the free-space lightwave transport system in visible light communication (VLC) application.

6.
Opt Express ; 22(3): 3468-74, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663637

RESUMO

A multiple-input-multiple-output (MIMO) visible light communication (VLC) system employing vertical cavity surface emitting laser (VCSEL) and spatial light modulators (SLMs) with 16-quadrature amplitude modulation (QAM)-orthogonal frequency-division multiplexing (OFDM) modulating signal is proposed and experimentally demonstrated. The transmission capacity of system is significantly increased by space-division demultiplexing scheme. With the assistance of low noise amplifier (LNA) and data comparator, good bit error rate (BER) performance, clear constellation map, and clear eye diagram are achieved for each optical channel. Such a MIMO VLC system would be attractive for providing services including data and telecommunication services. Our proposed system is suitably applicable to the lightwave communication system in wireless transmission.

7.
Opt Lett ; 39(2): 315-8, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24562135

RESUMO

An optical free-space wavelength-division-multiplexing (WDM) transport system employing vertical cavity surface emitting lasers and spatial light modulators with 16-quadrature amplitude modulation orthogonal frequency-division multiplexing modulating signals over a 17.5 m free-space link is proposed and demonstrated. With the help of a low-noise amplifier and data comparator, good bit error rate performance is obtained for each optical channel. Such an optical free-space WDM transport system would be attractive for providing services including data and telecommunication services.

8.
Opt Lett ; 39(7): 1721-4, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24686588

RESUMO

This Letter proposes and demonstrates a two-way lightwave subcarrier transmission system employing interleavers to deliver intensity-modulated CATV/phase-modulated RoF/intensity-remodulated 16-QAM-OFDM signals over two 20 km SMF links. To the best of our knowledge, it is the first time that interleavers have been employed in two-way lightwave subcarrier transmission systems. The downstream light is successfully intensity-remodulated with a 16-QAM-OFDM signal for uplink transmission. We obtained excellent performance from the CNR/CSO/CTB/BER for CATV/RoF/16-QAM-OFDM signal transmissions. The proposed systems offer impressive performance features to deliver hybrid CATV/RoF/16-QAM-OFDM signals.

9.
J Cancer ; 15(6): 1750-1761, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38370387

RESUMO

Despite advances in therapeutic strategies for colorectal cancer (CRC), CRC has a high disease incidence with significant morbidity and mortality worldwide. Notably, immunotherapy has shown limited efficacy in treating metastatic CRC, underscoring the need for alternative immunotherapeutic targets for the management of metastatic colorectal cancer (mCRC). In the present study, we evaluated the levels of the immune checkpoint proteins PD-L1, PD-L2 and B7-H3 in a large cohort retrospective study. We found that tumor B7-H3 (52.7%) was highly expressed in primary tumors compared to that in PD-L1 (33.6%) or PD-L2 (34.0%). Elevated B7-H3 expression was associated with advanced stage and the risk of distant metastasis and correlated with poor disease-free survival (DFS), suggesting that tumor B7-H3 was an independent prognostic factor associated with worse DFS in colon adenocarcinoma patients (COAD), especially high-risk COAD patients who received adjuvant chemotherapy. Furthermore, we found that B7-H3 significantly promoted cell proliferation and tumor growth in CRC. B7-H3 may stabilize EGFR to activate its downstream pathway for cancer cell proliferation and resistance to oxaliplatin (OXP). Dual targeting of B7-H3 and EGFR markedly rescued the susceptibility to chemotherapy in colorectal cancer cells in vitro and in vivo. Overall, these results showed that B7-H3 exhibited a high prevalence in COAD patients and was significantly associated with worse prognosis in COAD patients. Dual targeting of B7-H3 and EGFR signaling might be a potential therapeutic strategy for high-risk COAD patients.

10.
Neuro Oncol ; 26(3): 488-502, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-37882631

RESUMO

BACKGROUND: There is an urgent need to better understand the mechanisms associated with the development, progression, and onset of recurrence after initial surgery in glioblastoma (GBM). The use of integrative phenotype-focused -omics technologies such as proteomics and lipidomics provides an unbiased approach to explore the molecular evolution of the tumor and its associated environment. METHODS: We assembled a cohort of patient-matched initial (iGBM) and recurrent (rGBM) specimens of resected GBM. Proteome and metabolome composition were determined by mass spectrometry-based techniques. We performed neutrophil-GBM cell coculture experiments to evaluate the behavior of rGBM-enriched proteins in the tumor microenvironment. ELISA-based quantitation of candidate proteins was performed to test the association of their plasma concentrations in iGBM with the onset of recurrence. RESULTS: Proteomic profiles reflect increased immune cell infiltration and extracellular matrix reorganization in rGBM. ASAH1, SYMN, and GPNMB were highly enriched proteins in rGBM. Lipidomics indicates the downregulation of ceramides in rGBM. Cell analyses suggest a role for ASAH1 in neutrophils and its localization in extracellular traps. Plasma concentrations of ASAH1 and SYNM show an association with time to recurrence. CONCLUSIONS: We describe the potential importance of ASAH1 in tumor progression and development of rGBM via metabolic rearrangement and showcase the feedback from the tumor microenvironment to plasma proteome profiles. We report the potential of ASAH1 and SYNM as plasma markers of rGBM progression. The published datasets can be considered as a resource for further functional and biomarker studies involving additional -omics technologies.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/patologia , Metabolismo dos Lipídeos , Proteoma/metabolismo , Proteômica , Ceramidas/metabolismo , Neoplasias Encefálicas/patologia , Microambiente Tumoral , Glicoproteínas de Membrana
11.
Opt Express ; 21(20): 23655-61, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-24104277

RESUMO

A full-duplex lightwave transport system employing wavelength-division-multiplexing (WDM) and optical add-drop multiplexing techniques, as well as optical free-space transmission scheme is proposed and experimentally demonstrated. Over an 80-km single-mode fiber (SMF) and 2.4 m optical free-space transmissions, impressive bit error rate (BER) performance is obtained for long-haul fiber link and finite free-space transmission distance. Such a full-duplex lightwave transport system based on long-haul SMF and optical free-space transmissions has been successfully demonstrated, which cannot only present its advancement in lightwave application, but also reveal its simplicity and convenience for the real implementation. Our proposed systems are suitable for the lightwave communication systems in wired and wireless transmissions.

12.
Opt Lett ; 38(4): 404-6, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23455083

RESUMO

A bidirectional phase-modulated hybrid cable television/radio-over-fiber lightwave transport system employing fiber Bragg grating tilt filter as a phase modulation-to-intensity modulation conversion scheme is proposed and demonstrated. Impressive performances of carrier-to-noise ratio, composite second-order, composite triple-beat, and bit-error rate are obtained in our proposed systems over a combination of 40 km single-mode fiber-and 1.43 km photonic crystal fiber transmission.


Assuntos
Luz , Fibras Ópticas , Rádio/instrumentação , Televisão/instrumentação
13.
Opt Lett ; 38(13): 2345-7, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23811923

RESUMO

A bidirectional 16-quadrature amplitude modulation (QAM) orthogonal frequency-division multiplexing (OFDM) in-building network over 20 km single-mode fiber (SMF) and 15 m free-space visible light communication (VLC) transport is proposed and experimentally demonstrated. Good bit error rate performances and clear constellation maps are obtained for 16-QAM OFDM applications in our proposed in-building networks.

14.
Opt Lett ; 38(22): 4538-41, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24322068

RESUMO

A hybrid lightwave subcarrier CATV/16-QAM/16-QAM orthogonal frequency-division multiplexing (OFDM) transmission system employing light injection/optoelectronic feedback techniques and photonic crystal fiber (PCF) is proposed and demonstrated. Good performance of carrier-to-noise ratio (CNR), composite second order, and composite triple beat were obtained for the CATV band, and high CNR and low bit error rate values were achieved for the 16-QAM and 16-QAM OFDM bands over a combination of 80 km single-mode fiber (SMF) and 2.86 km PCF transport.

15.
Opt Express ; 20(4): 4219-24, 2012 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-22418180

RESUMO

A hybrid CATV/OFDM long-reach PON architecture is proposed and experimentally demonstrated. By multiplexing the OFDM and CATV signals in different frequency bands, the overall network structure is simplified and the available bandwidth for the OFDM signals is increased. Furthermore, by carefully adjusting the driving voltage of the employed CATV transmitter, the overall transmission performance can be optimized by eliminating a large amount of unwanted distortions. Unlike the current fiber optical CATV transport system in which the CATV signals need to be amplified in every 30 ~40 km transmission span, the proposed architecture has successfully extended the transmission span to 60 km. This can practically remove the needs of electrical power provisioning and monitoring between the central office (CO) and each local exchange (LE). Good transmission performances of carrier-to-noise ratio (CNR), composite second-order (CSO), composite triple beat (CTB) and bit error rate (BER) were obtained for the transmitted CATV and OFDM signals. All of these experimental results prove the practice and efficiency of the proposed architecture in providing simplicity and extended reach services to customers.

16.
Opt Express ; 20(9): 9919-24, 2012 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-22535084

RESUMO

A wavelength-division-multiplexing (WDM) visible light communiction (VLC) system employing red and green laser pointer lasers (LPLs) with directly modulating data signals is proposed and experimentally demonstrated. With the assistance of preamplifier and adaptive filter at the receiving sites, low bit error rate (BER) at 10 m/500 Mbps operation is obtained for each wavelength. The use of preamplifier and adaptive filter offer significant improvements for free-space transmission performance. Improved performance of BER of <10(-9), as well as better and clear eye diagram were achieved in our proposed WDM VLC systems. LPL features create a new category of good performance with high-speed data rate, long transmission length (>5m), as well as easy handling and installation. This proposed WDM VLC system reveals a prominent one to present its advancement in simplicity and convenience to be installed.


Assuntos
Amplificadores Eletrônicos , Lasers , Telecomunicações/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Micro-Ondas
17.
Nat Mater ; 9(8): 638-42, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20639895

RESUMO

The new paradigm of electronics, 'spintronics', promises to extend the functionality of information storage and processing in conventional electronics. The principal spintronics device, the 'spin valve', consists of two magnetic layers decoupled by a spin-transporting spacer, which allows parallel (on) and antiparallel (off) alignment of the magnetizations (spins) of the two magnetic layers. The device resistance then depends on the spin alignment controlled by the external magnetic field. In pursuit of semiconductor spintronics, there have been intensive efforts devoted to develop room-temperature magnetic semiconductors and also to incorporate both inorganic semiconductors and carbon-based materials as the spin-transporting channels. Molecule/organic-based magnets, which allow chemical tuning of electronic and magnetic properties, are a promising new class of magnetic materials for future spintronic applications. Here, we report the realization of an organic-based magnet as an electron spin polarizer in the standard spintronics device geometry. A thin non-magnetic organic semiconductor layer and an epitaxial ferromagnetic oxide film were employed to form a hybrid magnetic tunnel junction. The results demonstrate the spin-polarizing nature of the organic-based magnetic semiconductor, vanadium(TCNE: tetracyanoethylene)(x) (x approximately 2; T(c) approximately 400 K), and its function as a spin injector/detector in hybrid magnetic multilayer devices.

18.
Opt Express ; 19(15): 14000-7, 2011 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-21934761

RESUMO

A full-duplex lightwave transport system employing phase-modulated radio-over-fiber (RoF) and intensity-remodulated CATV signals in two-way transmission is proposed and experimentally demonstrated. The transmission performances of RoF and CATV signals are investigated in bidirectional way, with the assistance of only one optical sideband and optical single sideband (SSB) schemes at the receiving sites. The experimental results show that the limitation on the optical modulation index (OMI) of the downlink RoF signal can be relaxed due to the constant intensity of phase modulation scheme. Impressive transmission performances of bit error rate (BER), carrier-to-noise ratio (CNR), composite second-order (CSO), and composite triple-beat (CTB) were obtained over two 20-km single-mode fiber (SMF) links. This proposed system reveals an outstanding one with economy and convenience to be installed.

19.
Opt Express ; 19(27): 26928-35, 2011 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-22274276

RESUMO

A bidirectional fiber optical CATV transport system employing phase modulation (PM) scheme and frequency up-conversion technique to deal with downstream CATV signals, and using light injection-locked distributed feedback laser diode (DFB LD) as a duplex transceiver at the receiving site is proposed and experimentally demonstrated. With optimum injection wavelength and power level, a DFB LD is efficiently employed for both the transmitter and receiver operations. Such DFB LD is used to replace the functions of delay interferometer (DI) and CATV receiver, and also to be as the upstream light source. To the best of our knowledge, it is the first time to successfully utilize a DFB LD to detect the phase-modulated CATV signals. Impressive experimental results prove that our proposed systems not only can employ the PM scheme and the frequency up-conversion technique to optimize the overall performances of systems, but also can use an injection-locked DFB LD to detect the downstream phase-modulated CATV signals as well as to transmit the upstream CATV ones simultaneously.


Assuntos
Desenho Assistido por Computador , Tecnologia de Fibra Óptica/instrumentação , Dispositivos Ópticos , Telecomunicações/instrumentação , Televisão/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
20.
Phys Rev Lett ; 106(15): 156602, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21568590

RESUMO

We report the successful extraction of spin-polarized current from the organic-based room temperature ferrimagnetic semiconductor V[TCNE](x) (x∼2, TCNE: tetracyanoethylene; T(C)∼400 K, E(G)∼0.5 eV, σ(300 K)∼10(-2) S/cm) and its subsequent injection into a GaAs/AlGaAs light-emitting diode. The spin current tracks the magnetization of V[TCNE](x∼2), is weakly temperature dependent, and exhibits heavy-hole-light-hole asymmetry. This result has implications for room temperature spintronics and the use of inorganic materials to probe spin physics in organic and molecular systems.

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