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1.
Cancer Sci ; 115(7): 2235-2253, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38700108

RESUMO

Triple-negative breast cancer (TNBC) has greater infiltration of M2-like macrophages (TAMs), which enhances cancer cell invasion and leads to a poor prognosis. TNBC progression is mediated by both tumor cells and the tumor microenvironment (TME). Here we elucidate the mechanism of the interaction between TNBC cells and TAMs. In this study, we confirmed that CD44v5 is highly expressed in TNBC, which drives TNBC cell metastasis and promotes TAM polarization by co-localizing with IL4Rα and inhibiting its internalization and degradation, thereby promoting activation of the STAT3/IL6 signaling axis. At the same time, TAMs also facilitate TNBC cell metastasis by secreting IL-4, IL-6, and other cytokines, in which the IL-4/IL-4R/STAT3/IL-6 signaling axis plays the same role for TNBC cells responding to TAMs. Moreover, we found that the above progress could be suppressed when the CD44v5 domain was blocked. We demonstrated that the CD44v5/IL-4R/STAT3/IL-6 signaling pathway plays a key role in TNBC cell metastasis, and in TNBC cells inducing TAM polarization and responding to TAMs, promoting metastasis. Collectively, we suggest that the CD44v5 domain may be a promising target for regulating the TME of TNBC as well as treating TNBC.


Assuntos
Receptores de Hialuronatos , Fator de Transcrição STAT3 , Transdução de Sinais , Neoplasias de Mama Triplo Negativas , Microambiente Tumoral , Macrófagos Associados a Tumor , Humanos , Fator de Transcrição STAT3/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Receptores de Hialuronatos/metabolismo , Feminino , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia , Linhagem Celular Tumoral , Animais , Camundongos , Interleucina-6/metabolismo , Subunidade alfa de Receptor de Interleucina-4/metabolismo , Subunidade alfa de Receptor de Interleucina-4/genética , Interleucina-4/metabolismo
2.
Mol Carcinog ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980215

RESUMO

γ-Tocotrienol (γ-T3) is a major subtype of vitamin E, mainly extracted from palm trees, barley, walnuts, and other plants. γ-T3 has effects on anti-inflammation, anti-oxidation, and potential chemoprevention against malignancies. It is still uncompleted to understand the effect of γ-T3 on the inhibitory mechanism of cancer. This study aimed to investigate whether γ-T3 enhanced autophagy in gastric cancer and the underlying molecular mechanism. The results showed that γ-T3 (0-90 µmol/L) inhibited the proliferation of gastric cancer MKN45 cells and AGS cells, and arrested the cell cycle at the G0/G1 phase in a dose-dependent manner. Autophagy was increased in MKN45 cells treated with γ-T3 (0-45 µmol/L), especially at a dose of 30 µmol/L for 24 h. These effects were reversed by 3-methyladenine pretreatment. Furthermore, γ-T3 (30 µmol/L) also significantly downregulated the expression of pGSK-3ß (ser9) and ß-catenin protein in MKN45 cells, and γ-T3 (20 mg/kg b.w.) effectively decreased the growth of MKN45 cell xenografts in BABL/c mice. GSK-3ß inhibitor-CHIR-99021 reversed the negative regulation of GSK-3ß/ß-Catenin signaling and autophagy. Our findings indicated that γ-T3 enhances autophagy in gastric cancer cells mediated by GSK-3ß/ß-Catenin signaling, which provides new insights into the role of γ-T3 enhancing autophagy in gastric cancer.

3.
Opt Express ; 32(9): 16027-16039, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859240

RESUMO

We present the theory and experimental results of a microwave photonic (MWP) filter based instantaneous frequency measurement system. A quantum dash mode-locked laser is used as an optical frequency comb source. With up to 41 flat comb lines and a real-time feedback loop for comb shaping, a set of MWP filters with linear frequency responses for either linear unit or dB unit are experimentally demonstrated. The maximum measurement frequency can be up to 20 GHz limited by the available test-and-measurement instruments. By using one MWP filter, the root-mean-square error is 51∼66 MHz, which can be improved to 42.2 MHz for linear unit, and 30.7 MHz for dB unit by using two MWP filters together.

4.
Opt Express ; 32(1): 217-229, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175050

RESUMO

We investigate the capabilities and limitations of quantum-dash mode-locked lasers (QD-MLLDs) as optical frequency comb sources in coherent optical communication systems. We demonstrate that QD-MLLDs are on par with conventional single-wavelength narrow linewidth laser sources and can support high symbol rates and modulation formats. We manage to transmit 64 quadrature amplitude modulation (QAM) signals up to 80 GBd over 80 km of standard single-mode fiber (SSMF), which highlights the distinctive phase noise performance of the QD-MLLD. Using a 38.5 GHz (6 dB bandwidth) silicon photonic (SiP) modulator, we achieve a maximum symbol rate of 104 GBd with 16QAM signaling and a maximum net rate of 416 Gb/s per carrier in a single polarization setup and after 80 km-SSMF transmission. We also compare QD-MLLD performance with commercial narrow-linewidth integrable tunable laser assemblies (ITLAs) and explore their potential for use as local oscillators (LOs) and signal carriers. The QD-MLLD has 45 comb lines usable for transmission at a frequency spacing of 25 GHz, and an RF linewidth of 35 kHz.

5.
Molecules ; 29(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38202838

RESUMO

Enzyme biofuel cells (EBFCs) can convert chemical or biochemical energy in fuel into electrical energy, and therefore have received widespread attention. EBFCs have advantages that traditional fuel cells cannot match, such as a wide range of fuel sources, environmental friendliness, and mild reaction conditions. At present, research on EBFCs mainly focuses on two aspects: one is the use of nanomaterials with excellent properties to construct high-performance EBFCs, and the other is self-powered sensors based on EBFCs. This article reviews the applied nanomaterials based on the working principle of EBFCs, analyzes the design ideas of self-powered sensors based on enzyme biofuel cells, and looks forward to their future research directions and application prospects. This article also points out the key properties of nanomaterials in EBFCs, such as electronic conductivity, biocompatibility, and catalytic activity. And the research on EBFCs is classified according to different research goals, such as improving battery efficiency, expanding the fuel range, and achieving self-powered sensors.


Assuntos
Fontes de Energia Bioelétrica , Nanoestruturas , Eletricidade , Condutividade Elétrica , Eletrônica
6.
Appl Opt ; 62(32): 8696-8701, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38037987

RESUMO

We demonstrate photonic beamforming using a quantum-dash (QD) optical frequency comb (OFC) source. Thanks to the 25 GHz free spectral range (FSR) and up to 40 comb lines available from the QD OFC, we can implement phased antenna arrays (PAAs) with directional radiation and scanning. We consider two types of PAAs: a uniform linear array (ULA) and a uniform planar array (UPA). By selecting different comb lines with a programmable optical filter, we can tune the FSR of the OFC source and realize a discrete scanning function. We evaluate the beam squint of the ULAs, and the results show that we can achieve broadband operation. Finally, we show that we can achieve both directional radiation and scanning simultaneously using the UPA.

7.
BMC Microbiol ; 22(1): 203, 2022 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-35987607

RESUMO

PURPOSE: The objective of this study was to investigate the molecular characteristics and potential resistance mechanisms of linezolid-resistant (LZR) Staphylococcus capitis isolates from a tertiary hospital in China. METHODS: S. capitis isolates were obtained from clinical patient specimens; three of the isolates came from blood cultures and one from the hydrothorax. The agar dilution and E-test methods were used to identify antibiotic resistance. The chloramphenicol-florfenicol resistance (cfr) gene carrier status of the strains was determined by PCR. Whole-genome sequencing (WGS) was used to identify point mutations and L3, L4, and L22 mutations and to study the genetic environment of the cfr gene and the relationships between strains. RESULTS: The 4 isolates obtained in this study were all linezolid-resistant Staphylococcus strains. A similar of susceptibility profile pattern was observed in all four S. capitis strains, each of which exhibited a multidrug-resistant phenotype. A potentially novel mutation, C2128T, was identified, and the cfr genes of S. capitis strains were all positive. Additionally, the same mutations (C2128T and G2600T) were identified in all 23S rRNA sequences of the isolates, whereas mutations were lacking in the L3, L4, and L22 ribosomal proteins. The genetic environments surrounding cfr were identical in all four isolates. A schematic diagram of the phylogenetic tree showed that they were closely related to AYP1020, CR01, and TW2795, and a total of seven drug resistance genes were identified in these strains. CONCLUSIONS: The study indicated that the resistance of the Staphylococcus capitis strains to linezolid was caused by multiple mechanisms, and a potential novel mutation, C2128T, that may have an impact on bacterial resistance was identified.


Assuntos
Farmacorresistência Bacteriana , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Staphylococcus capitis , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Genes de RNAr , Humanos , Linezolida/farmacologia , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Mutação , Filogenia , RNA Ribossômico 23S/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus capitis/genética
8.
Opt Express ; 30(3): 3205-3214, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35209585

RESUMO

Chip-scale optical frequency comb sources are ideal compact solutions to generate high speed optical pulses for applications in wavelength division multiplexing (WDM) and high-speed optical signal processing. Our previous studies have concentrated on the use of quantum dash based lasers, but here we present results from an InAs/InP quantum dot (QDot) C-band passively mode-locked laser (MLL) for frequency comb generation. By using this single-section QDot-MLL we demonstrate an aggregate line rate of 12.544 Tbit/s 16QAM data transmission capacity for both back-to-back (B2B) and over 100-km of standard single mode fiber (SSMF). This finding highlights the viability for InAs/InP QDot lasers to be used as a low-cost optical source for large-scale networks.

9.
Opt Lett ; 47(5): 1133-1136, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35230309

RESUMO

We demonstrate a reconfigurable microwave photonic (MWP) filter using a quantum dash (QDash) mode-locked laser (MLL) that can generate an optical frequency comb (OFC) with ∼50 comb lines and a free spectral range of 25 GHz. Thanks to the large number of comb lines, the MWP filter responses can be easily programmed by tailoring the OFC spectrum. We implement MWP filter responses with Gaussian, sinc, flat-top, and multiple peaks, as well as demonstrate that tuning of the central frequency. We achieve a minimum 3 dB bandwidth of ∼100 MHz for a sinc-shaped MWP filter, while the maximum out-of-band rejection can be up to ∼30 dB with Gaussian apodization. Our results show that the QDash-MLL is a promising OFC source for developing integrated and reconfigurable MWP filters.

10.
Opt Express ; 29(11): 16164-16174, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154184

RESUMO

We have developed and experimentally demonstrated a highly coherent and low noise InP-based InAs quantum dash (QDash) buried heterostructure (BH) C-band passively mode-locked laser (MLL) with a pulse repetition rate of 25 GHz for fiber-wireless integrated fronthaul 5G new radio (NR) systems. The device features a broadband spectrum providing over 46 equally spaced highly coherent and low noise optical channels with an optical phase noise and integrated relative intensity noise (RIN) over a frequency range of 10 MHz to 20 GHz for each individual channel typically less than 466.5 kHz and -130 dB/Hz, respectively, and an average total output power of ∼50 mW per facet. Moreover, the device exhibits low RF phase noise with measured RF beat-note linewidth down to 3 kHz and estimated timing jitter between any two adjacent channels of 5.5 fs. By using this QDash BH MLL device, we have successfully demonstrated broadband optical heterodyne based radio-over-fiber (RoF) fronthaul wireless links at 5G NR in the underutilized spectrum of around 25 GHz with a total bit rate of 16-Gb/s. The device performance is experimentally evaluated in an end-to-end fiber-wireless system in real-time in terms of error vector magnitude (EVM) and bit error rate (BER) by generating, transmitting and detecting 4-Gbaud 16-QAM RF signals over 0.5-m to 2-m free-space indoor wireless channel through a total length of 25.22 km standard single mode fiber (SSMF) with EVM and BER under 8.4% and 2.9 × 10-5, respectively. The intrinsic characteristics of the device in conjunction with its system transmission performance indicate that QDash BH MLLs can be readily used in fiber-wireless integrated systems of 5G and beyond wireless communication networks.

11.
J Cardiovasc Pharmacol ; 78(6): 819-825, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34524259

RESUMO

ABSTRACT: The energy used by the heart is generated mainly by the metabolism of fatty acids and glucose. Trimetazidine (TMZ) inhibits fatty acid metabolism and is used for the treatment of heart diseases such as heart failure. 3-Bromopyruvate (3-BrPA) can suppress glucose metabolism, and it is considered a promising candidate agent for tumor therapy. Because TMZ and 3-BrPA can separately inhibit the 2 main cardiac energy sources, it is necessary to investigate the effects of 3-BrPA combined with TMZ on the heart. Forty male Wistar rats were randomly divided into 4 groups: a control group, a TMZ group, a 3-BrPA group, and a 3-BrPA + TMZ group. Weight was recorded every day, and echocardiography was performed 14 days later. Heart function, the levels of adenosine triphosphate, oxidative stress-related factors (ROS, glutathione, oxidized glutathione, malondialdehyde, superoxide dismutase and total antioxidant capacity), and apoptosis in heart tissues were assessed to evaluate the effects of 3-BrPA and TMZ on the heart. In our study, no obvious changes occurred in the 3-BrPA group or the TMZ group compared with the control group. The combination of 3-BrPA and TMZ worsened heart function, decreased adenosine triphosphate levels, and increased oxidative stress and myocardial apoptosis. In conclusion, 3-BrPA and TMZ are not recommended for concurrent use.


Assuntos
Apoptose/efeitos dos fármacos , Fármacos Cardiovasculares/toxicidade , Inibidores Enzimáticos/toxicidade , Cardiopatias/induzido quimicamente , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Piruvatos/toxicidade , Trimetazidina/toxicidade , Trifosfato de Adenosina/metabolismo , Animais , Cardiotoxicidade , Metabolismo Energético/efeitos dos fármacos , Cardiopatias/metabolismo , Cardiopatias/patologia , Cardiopatias/fisiopatologia , Masculino , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos Wistar , Transdução de Sinais , Função Ventricular Esquerda/efeitos dos fármacos
12.
Opt Express ; 28(4): 4587-4593, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32121692

RESUMO

This paper presents an InAs/InP quantum dash (QD) C-band passively mode-locked laser (MLL) with a channel spacing of 34.224 GHz. By using this QD-MLL we demonstrate an aggregate 5.376 Tbit/s PAM-4 data transmission capacity both for back-to-back (B2B) and over 25-km of standard single mode fiber (SSMF). This represents the first demonstration of QD-MLL acting as error-free operation at an aggregate data transmission capacity of 5.376 Tbit/s for some filtered individual channels. This finding highlights the viability for InAs/InP QD lasers to be used as a low-cost optical source for data center networks.

13.
Opt Express ; 27(24): 35368-35375, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31878707

RESUMO

We have developed and experimentally demonstrated a novel monolithic InAs/InP quantum-dash dual-wavelength distributed feedback (QD DW-DFB) C-band laser as a compact optical beat source to generate millimeter-wave (MMW) signals. The device uses a common gain medium in a single cavity structure for simultaneous correlated and stable dual-mode lasing in the 1550-nm wavelength range. A record narrow optical linewidth down to 15.83 kHz and average relative intensity noise (RIN) as low as -158.3 dB/Hz from 10 MHz to 20 GHz are experimentally demonstrated for the two optical modes generated by the laser. As a result, the beat note between these two lasing modes generates spectrally pure MMW signals between 46 GHz and 48 GHz. Such an efficient, coherent, and compact optical source is extremely attractive for applications in MMW systems, such as Radar and fiber-wireless integrated fronthaul for 5G and beyond.

14.
Arch Toxicol ; 93(10): 2993-3003, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506784

RESUMO

As one of the isoprenoids and widely derived from many fruits and vegetables, ß-ionone (BI) has a potent inhibitory proliferation of cancer cells in vitro and in vivo. However, its exact mechanism is still uncompleted understood and needs to be further verified. Cyclooxygenase-2 (COX-2), as a potential target of cancer chemoprevention, has been played pivotal roles in proliferation of tumor cells and carcinogenesis. Thus, the objective of present study was to determine that BI inhibited the activity of COX-2 in breast cancer and related to cancer cell models. Cell proliferation, DNA synthesis, the distribution of cell cycle, apoptosis induction and the expression of P38-MAPK protein were determined in MCF-7 cells by methylene blue, 3H-thymidine (TdR) incorporation, flow cytometry, TUNEL and Western blotting assays. Quinone reductase (QR) activity was determined in murine hepatoma Hepa1c1c7 cells by enzyme-linked immunosorbent assay (ELISA). The expression of COX-2 in a phorbol-12-myristate-13-acetate (PMA)-induced cell model and mammary tumor tissues was examined by Western blotting and immunohistochemistry. The results showed that BI significantly inhibited cell proliferation and DNA synthesis, arrested the distribution of cell cycle at the S phase or decreased proteins related to cell cycle such as cyclin D1 and CDK4, induced apoptosis and increased the expression of p-P38 in MCF-7 cells. BI at low doses (< 50 µmol/L) significantly increased QR activity, decreased the expression of COX-2 protein and prostaglandin E2 (PEG2) release in cell models. In addition, BI also significantly decreased the expression of COX-2 protein in rat mammary tumor tissues. Therefore, our findings indicate that BI possesses inhibitory proliferation of breast cancer cells through down-regulation of COX-2 activity.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/efeitos dos fármacos , Norisoprenoides/farmacologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Carcinoma Hepatocelular/enzimologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Neoplasias Hepáticas/enzimologia , Células MCF-7 , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/patologia , Camundongos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Norisoprenoides/administração & dosagem , Ratos
15.
Anesth Analg ; 123(4): 1008-17, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27529322

RESUMO

BACKGROUND: Dexmedetomidine (DEX) has inherent neuroprotective properties that have been attributed to the activation of prosurvival kinases. However, the impact of supraclinical doses of DEX on neuroapoptosis and neuronal viability has not been determined. METHODS: Rat pups and primary neuronal cells were treated with DEX or ketamine (KET) alone or in combination. Neuroapoptosis was measured by cleaved-caspase-3 expression and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining in brain sections. Expression of prosurvival kinases was measured by Western blot. We measured the impact of DEX with and without α1-adrenergic receptor blockade on the viability of primary neuronal cell cultures. RESULTS: Increasing the cumulative dose of DEX resulted in elevated levels of neuroapoptosis in vivo. Low doses increased, whereas high dose decreased phosphorylation of the prosurvival kinases. KET alone and in combination with DEX produced a greater degree of apoptosis and reductions in expression of these protein kinases than DEX alone. Increasing concentrations of DEX decreased, while coadministration of an α1-adrenergic receptor blocker preserved neuronal viability in vitro. CONCLUSIONS: Although DEX is neuroprotective at clinical doses, high cumulative doses and concentrations induce neuroapoptosis, in vivo and in vitro, respectively. Because the current dosing schedules used in humans yield plasma levels that are substantially below concentrations that induce neurotoxicity, low-dose DEX should not be neurotoxic and has the potential to be a neuroprotective adjuvant.


Assuntos
Apoptose/efeitos dos fármacos , Dexmedetomidina/administração & dosagem , Dexmedetomidina/toxicidade , Neurônios/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Apoptose/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/toxicidade , Neurônios/patologia , Neurônios/fisiologia , Gravidez , Ratos , Ratos Sprague-Dawley
16.
Hepatology ; 59(3): 935-46, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24037855

RESUMO

UNLABELLED: Although gankyrin is involved in the tumorigenicity and metastasis of some malignancies, the role of gankyrin in cholangiocarcinoma (CCA) is unclear. In this study we investigated the expression of gankyrin in human CCA tissues and cell lines. The effects of gankyrin on CCA tumor growth and metastasis were determined both in vivo and in vitro. The results showed that gankyrin was overexpressed in CCA tissues and cell lines. Gankyrin expression was associated with CCA histological differentiation, TNM stage, and metastasis. The multivariate Cox analysis revealed that gankyrin was an independent prognostic indicator for overall survival. Gankyrin overexpression promoted CCA cell proliferation, migration, and invasion, while gankyrin knockdown inhibited CCA tumor growth, metastasis, and induced Rb-dependent senescence and G1 phase cell cycle arrest. Gankyrin increased the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and promoted the nuclear translocation of p-STAT3. Suppression of STAT3 signaling by small interfering RNA (siRNA) or STAT3 inhibitor interfered with gankyrin-mediated carcinogenesis and metastasis, while interleukin (IL)-6, a known upstream activator of STAT3, could restore the proliferation and migration of gankyrin-silenced CCA cells. The IL-6 level was decreased by gankyrin knockdown, while increased by gankyrin overexpression. Gankyrin regulated IL-6 expression by way of facilitating the phosphorylation of Rb; meanwhile, rIL-6 treatment increased the expression of gankyrin, suggesting that IL-6 was regulated by a positive feedback loop involving gankyrin in CCA. In the xenograft experiments, gankyrin overexpression accelerated tumor formation and increased tumor weight, whereas gankyrin knockdown showed the opposite effects. The in vivo spontaneous metastasis assay revealed that gankyrin promoted CCA metastasis through IL-6/STAT3 signaling pathway. CONCLUSION: Gankyrin is crucial for CCA carcinogenesis and metastasis by activating IL-6/STAT3 signaling pathway through down-regulating Rb protein.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Ductos Biliares Intra-Hepáticos/metabolismo , Colangiocarcinoma/metabolismo , Interleucina-6/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fator de Transcrição STAT3/metabolismo , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Pontos de Checagem do Ciclo Celular/fisiologia , Movimento Celular/fisiologia , Colangiocarcinoma/genética , Colangiocarcinoma/secundário , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica/patologia , Valor Preditivo dos Testes , Prognóstico , Complexo de Endopeptidases do Proteassoma/genética , Proteínas Proto-Oncogênicas/genética , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais/fisiologia
17.
Mol Cancer ; 13: 133, 2014 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-24884809

RESUMO

BACKGROUND: Arsenic trioxide has been demonstrated as an effective anti-cancer drug against leukemia and solid tumors both in vitro and in vivo. However, recent phase II trials demonstrated that single agent arsenic trioxide was poorly effective against hepatocellular carcinoma (HCC), which might be due to drug resistance. METHODS: Mutation detection of p53 gene in arsenic trioxide resistant HCC cell lines was performed. The therapeutic effects of arsenic trioxide and Nutlin-3 on HCC were evaluated both in vitro and in vivo. A series of experiments including MTT, apoptosis assays, co-Immunoprecipitation, siRNA transfection, lentiviral infection, cell migration, invasion, and epithelial-mesenchy-mal transition (EMT) assays were performed to investigate the underlying mechanisms. RESULTS: The acquisition of p53 mutation contributed to arsenic trioxide resistance and enhanced metastatic potential of HCC cells. Mutant p53 (Mutp53) silence could re-sensitize HCC resistant cells to arsenic trioxide and inhibit the metastatic activities, while mutp53 overexpression showed the opposite effects. Neither arsenic trioxide nor Nutlin-3 could exhibit obvious effects against arsenic trioxide resistant HCC cells, while combination of them showed significant effects. Nutlin-3 can not only increase the intracellular arsenicals through inhibition of p-gp but also promote the p73 activation and mutp53 degradation mediated by arsenic trioxide. In vivo experiments indicated that Nutlin-3 can potentiate the antitumor activities of arsenic trioxide in an orthotopic hepatic tumor model and inhibit the metastasis to lung. CONCLUSIONS: Acquisitions of p53 mutations contributed to the resistance of HCC to arsenic trioxide. Nutlin-3 could overcome arsenic trioxide resistance and inhibit tumor metastasis through p73 activation and promoting mutant p53 degradation mediated by arsenic trioxide.


Assuntos
Antineoplásicos/farmacologia , Arsenicais/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , Imidazóis/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Óxidos/farmacologia , Piperazinas/farmacologia , Proteína Supressora de Tumor p53/genética , Animais , Trióxido de Arsênio , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Nus , Mutação , Transplante de Neoplasias , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transdução de Sinais , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
18.
Hepatology ; 57(5): 1847-57, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23299930

RESUMO

UNLABELLED: The increasing incidence of hepatocellular carcinoma (HCC) is of great concern not only in the United States but throughout the world. Although sorafenib, a multikinase inhibitor with antiangiogenic and antiproliferative effects, currently sets the new standard for advanced HCC, tumor response rates are usually quite low. An understanding of the underlying mechanisms for sorafenib resistance is critical if outcomes are to be improved. In this study we tested the hypothesis that hypoxia caused by the antiangiogenic effects of sustained sorafenib therapy could induce sorafenib resistance as a cytoprotective adaptive response, thereby limiting sorafenib efficiency. We found that HCCs, clinically resistant to sorafenib, exhibit increased intratumor hypoxia compared with HCCs before treatment or HCCs sensitive to sorafenib. Hypoxia protected HCC cells against sorafenib and hypoxia-inducible factor 1 (HIF-1α) was required for the process. HCC cells acquired increased P-gp expression, enhanced glycolytic metabolism, and increased nuclear factor kappa B (NF-κB) activity under hypoxia. EF24, a molecule having structural similarity to curcumin, could synergistically enhance the antitumor effects of sorafenib and overcome sorafenib resistance through inhibiting HIF-1α by sequestering it in cytoplasm and promoting degradation by way of up-regulating Von Hippel-Lindau tumor suppressor (VHL). Furthermore, we found that sustained sorafenib therapy led to increased intratumor hypoxia, which was associated with sorafenib sensitivity in HCC subcutaneous mice tumor models. The combination of EF24 and sorafenib showed synergistically effects against metastasis both in vivo and in vitro. Synergistic tumor growth inhibition effects were also observed in subcutaneous and orthotopic hepatic tumors. CONCLUSION: Hypoxia induced by sustained sorafenib treatment confers sorafenib resistance to HCC through HIF-1α and NF-κB activation. EF24 overcomes sorafenib resistance through VHL-dependent HIF-1α degradation and NF-κB inactivation. EF24 in combination with sorafenib represents a promising strategy for HCC.


Assuntos
Compostos de Benzilideno/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Hipóxia/fisiopatologia , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Piperidonas/farmacologia , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimioterapia Combinada , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , NF-kappa B/metabolismo , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Compostos de Fenilureia/farmacologia , Sorafenibe , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Front Mol Neurosci ; 17: 1342233, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840775

RESUMO

Introduction: Disrupted in schizophrenia-1 (DISC1) is a scaffolding protein whose mutated form has been linked to schizophrenia, bipolar affective disorders, and recurrent major depression. DISC1 regulates multiple signaling pathways involved in neurite outgrowth and cortical development and binds directly to glycogen synthase kinase-3ß (GSK-3ß). Since ketamine activates GSK-3ß, we examined the impact of ketamine on DISC1 and GSK-3ß expression. Methods: Postnatal day 7 rat pups were treated with ketamine with and without the non-specific GSK-3ß antagonist, lithium. Cleaved-caspase-3, GSK-3ß and DISC1 levels were measured by immunoblots and DISC1 co-localization in neurons by immunofluorescence. Binding of DISC1 to GSK-3ß was determined by co-immunoprecipitation. Neurite outgrowth was determined by measuring dendrite and axon length in primary neuronal cell cultures treated with ketamine and lithium. Results: Ketamine decreased DISC1 in a dose and time-dependent manner. This corresponded to decreases in phosphorylated GSK-3ß, which implicates increased GSK-3ß activity. Lithium significantly attenuated ketamine-induced decrease in DISC1 levels. Ketamine decreased co-immunoprecipitation of DISC1 with GSK-3ß and axonal length. Conclusion: These findings confirmed that acute administration of ketamine decreases in DISC1 levels and axonal growth. Lithium reversed this effect. This interaction provides a link between DISC1 and ketamine-induced neurodegeneration.

20.
ACS Appl Bio Mater ; 7(5): 2695-2703, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38701372

RESUMO

Gold nanoclusters (AuNCs), with customized structures and diverse optical properties, are promising optical materials. Constructing composite systems by the assembly and incorporation of AuNCs can utilize their optical properties to achieve diagnostic and therapeutic applications in the biological field. Therefore, the exploration of the assembly behaviors of AuNCs and the enhancement of their performance has attracted widespread interest. In this review, we introduce multiple interactions and assembly modes that are prevalent in nanocomposites and microcomposites based on AuNCs. Then, the functions of AuNC composites for bioapplications are demonstrated in detail. These composite systems have inherited and enhanced the inherent optical performances of the AuNCs to meet diverse requirements for biological sensing and optical treatments. Finally, we discuss the prospects of AuNC composites and highlight the challenges and opportunities in biomedical applications.


Assuntos
Materiais Biocompatíveis , Ouro , Teste de Materiais , Nanopartículas Metálicas , Ouro/química , Materiais Biocompatíveis/química , Nanopartículas Metálicas/química , Humanos , Tamanho da Partícula , Nanocompostos/química , Processos Fotoquímicos
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