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1.
J Colloid Interface Sci ; 666: 76-87, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38583212

RESUMO

The pressing demand for propylene has spurred intensive research on the catalytic dehydrogenation of propane to produce propylene. Gallium-based catalysts are regarded as highly promising due to their exceptional dehydrogenation activity in the presence of CO2. However, the inherent coking issue associated with high temperature reactions poses a constraint on the stability development of this process. In this study, we employed the electrospinning method to prepare a range of Ga2O3-Al2O3 mixed oxide one-dimensional nanofiber catalysts with varying molar ratios for CO2 oxidative dehydrogenation of propane (CO2-OPDH). The propane conversion was up to 48.4 % and the propylene selectivity was high as 96.8 % at 500 °C, the ratio of propane to carbon dioxide is 1:2. After 100 h of reaction, the catalyst still maintains approximately 10 % conversion and exhibits a propylene selectivity of around 98 %. The electrospinning method produces one-dimensional nanostructures with a larger specific surface area, unique multi-stage pore structure and low-coordinated Ga3+, which enhances mass transfer and accelerates reaction intermediates. This results in less coking and improved catalyst stability. The high activity of the catalyst is attributed to an abundance of low-coordinated Ga3+ ions associated with weak/medium-strong Lewis acid centers. In situ infrared analysis reveals that the reaction mechanism involves a two-step dehydrogenation via propane isocleavage, with the second dehydrogenation of Ga-OR at the metal-oxygen bond being the decisive speed step.

2.
Cell ; 187(6): 1422-1439.e24, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38447573

RESUMO

Neutrophils, the most abundant and efficient defenders against pathogens, exert opposing functions across cancer types. However, given their short half-life, it remains challenging to explore how neutrophils adopt specific fates in cancer. Here, we generated and integrated single-cell neutrophil transcriptomes from 17 cancer types (225 samples from 143 patients). Neutrophils exhibited extraordinary complexity, with 10 distinct states including inflammation, angiogenesis, and antigen presentation. Notably, the antigen-presenting program was associated with favorable survival in most cancers and could be evoked by leucine metabolism and subsequent histone H3K27ac modification. These neutrophils could further invoke both (neo)antigen-specific and antigen-independent T cell responses. Neutrophil delivery or a leucine diet fine-tuned the immune balance to enhance anti-PD-1 therapy in various murine cancer models. In summary, these data not only indicate the neutrophil divergence across cancers but also suggest therapeutic opportunities such as antigen-presenting neutrophil delivery.


Assuntos
Apresentação de Antígeno , Neoplasias , Neutrófilos , Animais , Humanos , Camundongos , Antígenos de Neoplasias , Leucina/metabolismo , Neoplasias/imunologia , Neoplasias/patologia , Neutrófilos/metabolismo , Linfócitos T , Análise da Expressão Gênica de Célula Única
3.
Cancer Cell ; 42(2): 180-197, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38350421

RESUMO

The past decade has witnessed significant advances in the systemic treatment of advanced hepatocellular carcinoma (HCC). Nevertheless, the newly developed treatment strategies have not achieved universal success and HCC patients frequently exhibit therapeutic resistance to these therapies. Precision treatment represents a paradigm shift in cancer treatment in recent years. This approach utilizes the unique molecular characteristics of individual patient to personalize treatment modalities, aiming to maximize therapeutic efficacy while minimizing side effects. Although precision treatment has shown significant success in multiple cancer types, its application in HCC remains in its infancy. In this review, we discuss key aspects of precision treatment in HCC, including therapeutic biomarkers, molecular classifications, and the heterogeneity of the tumor microenvironment. We also propose future directions, ranging from revolutionizing current treatment methodologies to personalizing therapy through functional assays, which will accelerate the next phase of advancements in this area.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Imunoterapia/métodos , Microambiente Tumoral
4.
Gastroenterology ; 2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38262581

RESUMO

BACKGROUND & AIMS: Despite the increasing number of treatment options available for liver cancer, only a small proportion of patients achieve long-term clinical benefits. Here, we aim to develop new therapeutic approaches for liver cancer. METHODS: A compound screen was conducted to identify inhibitors that could synergistically induce senescence when combined with cyclin-dependent kinase (CDK) 4/6 inhibitor. The combination effects of CDK4/6 inhibitor and exportin 1 (XPO1) inhibitor on cellular senescence were investigated in a panel of human liver cancer cell lines and multiple liver cancer models. A senolytic drug screen was performed to identify drugs that selectively killed senescent liver cancer cells. RESULTS: The combination of CDK4/6 inhibitor and XPO1 inhibitor synergistically induces senescence of liver cancer cells in vitro and in vivo. The XPO1 inhibitor acts by causing accumulation of RB1 in the nucleus, leading to decreased E2F signaling and promoting senescence induction by the CDK4/6 inhibitor. Through a senolytic drug screen, cereblon (CRBN)-based proteolysis targeting chimera (PROTAC) ARV-825 was identified as an agent that can selectively kill senescent liver cancer cells. Up-regulation of CRBN was a vulnerability of senescent liver cancer cells, making them sensitive to CRBN-based PROTAC drugs. Mechanistically, we find that ubiquitin specific peptidase 2 (USP2) directly interacts with CRBN, leading to the deubiquitination and stabilization of CRBN in senescent liver cancer cells. CONCLUSIONS: Our study demonstrates a striking synergy in senescence induction of liver cancer cells through the combination of CDK4/6 inhibitor and XPO1 inhibitor. These findings also shed light on the molecular processes underlying the vulnerability of senescent liver cancer cells to CRBN-based PROTAC therapy.

5.
Nat Nanotechnol ; 18(8): 867-874, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37322146

RESUMO

The Berry curvature dipole (BCD) is a key parameter that describes the geometric nature of energy bands in solids. It defines the dipole-like distribution of Berry curvature in the band structure and plays a key role in emergent nonlinear phenomena. The theoretical rationale is that the BCD can be generated at certain symmetry-mismatched van der Waals heterointerfaces even though each material has no BCD in its band structure. However, experimental confirmation of such a BCD induced via breaking of the interfacial symmetry remains elusive. Here we demonstrate a universal strategy for BCD generation and observe BCD-induced gate-tunable spin-polarized photocurrent at WSe2/SiP interfaces. Although the rotational symmetry of each material prohibits the generation of spin photocurrent under normal incidence of light, we surprisingly observe a direction-selective spin photocurrent at the WSe2/SiP heterointerface with a twist angle of 0°, whose amplitude is electrically tunable with the BCD magnitude. Our results highlight a BCD-spin-valley correlation and provide a universal approach for engineering the geometric features of twisted heterointerfaces.

6.
Small ; 19(4): e2204133, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36420659

RESUMO

The acquired resistance to Osimertinib (AZD9291) greatly limits the clinical benefit of patients with non-small cell lung cancer (NSCLC), whereas AZD9291-resistant NSCLCs are prone to metastasis. It's challenging to overcome AZD9291 resistance and suppress metastasis of NSCLC simultaneously. Here, a nanocatalytic sensitizer (VF/S/A@CaP) is proposed to deliver Vitamin c (Vc)-Fe(II), si-OTUB2, ASO-MALAT1, resulting in efficient inhibition of tumor growth and metastasis of NSCLC by synergizing with AHP-DRI-12, an anti-hematogenous metastasis inhibitor by blocking the amyloid precursor protein (APP)/death receptor 6 (DR6) interaction designed by our lab. Fe2+ released from Vc-Fe(II) generates cytotoxic hydroxyl radicals (•OH) through Fenton reaction. Subsequently, glutathione peroxidase 4 (GPX4) is consumed to sensitize AZD9291-resistant NSCLCs with high mesenchymal state to ferroptosis due to the glutathione (GSH) depletion caused by Vc/dehydroascorbic acid (DHA) conversion. By screening NSCLC patients' samples, metastasis-related targets (OTUB2, LncRNA MALAT1) are confirmed. Accordingly, the dual-target knockdown plus AHP-DRI-12 significantly suppresses the metastasis of AZD9291-resistant NSCLC. Such modality leads to 91.39% tumor inhibition rate in patient-derived xenograft (PDX) models. Collectively, this study highlights the vulnerability to ferroptosis of AZD9291-resistant tumors and confirms the potential of this nanocatalytic-medicine-based modality to overcome critical AZD9291 resistance and inhibit metastasis of NSCLC simultaneously.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Ferroptose , Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Receptores ErbB/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Compostos Ferrosos , Linhagem Celular Tumoral
7.
Biomaterials ; 288: 121705, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36002347

RESUMO

Inflammation is the main driver of the aggravation of arteriosclerosis, and the complex inflammatory response in plaque is usually the result of the interaction of various cells and cytokines. Therefore, it is difficult to comprehensively regulate the inflammatory process of arteriosclerosis by intervening a single target, resulting in the poor effect of existing treatment method. Based on our clinical findings that P-selectin stably and highly expressed in patients' plaque endothelial cells, the programmed prodrug, low molecular weight heparin-indomethacin nanoparticles (LI NPs), were established as anti-inflammatory agent to multiphase inhibit arteriosclerosis by cascade interference of P-selectin. Structurally, LI NPs was obtained by simple esterification of low molecular weight heparin and indomethacin without any additives, guaranteeing the biocompatibility and applicability of LI NPs. Functionally, LI NPs could interfere with P-selectin in the inflammatory process, such as inhibiting macrophage adhesion, reducing the secretion of inflammatory factors, and inducing macrophage apoptosis. In the arteriosclerosis mice model, LI NPs significantly reduced the plaque area and showed satisfactory curative effect, which is related to the intervention of the multiphase inflammation between endothelial cells and macrophages. In conclusion, the programmed prodrug LI NPs offered a promising approach for the clinical therapy of arteriosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Pró-Fármacos , Animais , Aterosclerose/tratamento farmacológico , Células Endoteliais , Retroalimentação , Heparina de Baixo Peso Molecular , Indometacina/uso terapêutico , Inflamação/tratamento farmacológico , Camundongos , Selectina-P , Placa Aterosclerótica/tratamento farmacológico , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico
8.
ACS Nano ; 16(2): 3417-3431, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35156370

RESUMO

The functional status of innate immune cells is a considerable determinant of effective antitumor immune response. However, the triple-negative breast cancer tumor microenvironment with high lactic acid metabolism and high antioxidant levels limits immune cell survival, differentiation, and function. Here, we determine that the tumor microenvironment-responsive nano-ultrasonic contrast agent Pt(IV)/CQ/PFH NPs-DPPA-1 boosts the ratio of mature dendritic cells (mDCs) and proinflammatory macrophages by reprogramming the metabolism of immature DCs (iDCs) and tumor-associated macrophages (TAMs). Specifically, platinum(IV) in cancer cells or iDCs was reduced to cisplatin, which can increase the intracellular content of ROS and therefore enhance the ratio of mDCs and apoptotic tumor cells. Meanwhile, chloroquine (CQ) released from nanoparticles (NPs) minimizes protective autophagy caused by cisplatin in tumor cells and reprograms the metabolism of TAMs to enhance the proportion of proinflammatory macrophages, achieving a superior synergistic effect of chemoimmunotherapy combined with Pt(IV) and anti-PD-L1 peptide (DPPA-1). Furthermore, perfluorohexane (PFH) in NPs realizes monitoring treatment corresponding to ultrasound. Collectively, the nano-ultrasonic contrast agent supports a candidate for monitoring treatment and augmenting antitumor chemoimmunotherapy by suppressing tumor cell autophagy and reprogramming immunocyte metabolism.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Autofagia , Linhagem Celular Tumoral , Meios de Contraste/farmacologia , Humanos , Nanopartículas/química , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Microambiente Tumoral
9.
J Thorac Cardiovasc Surg ; 163(4): 1349-1357.e5, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-32499074

RESUMO

OBJECTIVE: The study objective was to assess the impact of chronic total occlusion on long-term graft failure and outcomes in patients who underwent coronary artery bypass grafting. METHODS: We conducted an observational study involving a single-center subgroup of the CORONARY trial. At 6 to 9 years after coronary artery bypass grafting, all alive patients were invited for coronary computed tomography angiography and clinical follow-up. We assessed the association between chronic total occlusion graft and failing graft showing Fitzgibbon type B or O. Risk factors associated with chronic total occlusion graft failure were assessed. The impact of chronic total occlusion on clinical outcomes was analyzed, including death, myocardial infarction, and repeated revascularization. RESULTS: A total of 349 patients undergoing coronary artery bypass grafting were enrolled between May 2007 and October 2011. Of 301 alive patients at follow-up time (median, 6.8 years; interquartile range, 6.0-8.0 years), repeat coronary computed tomography angiography was performed in 206 patients (68.4%) with 723 grafts (154 chronic total occlusion grafts and 569 nonchronic total occlusion grafts). Chronic total occlusion graft was significantly associated with an increased risk of long-term graft failure after adjustment for patient- and graft-level characteristics (adjusted odds ratio, 2.27; 95% confidence interval, 1.42-3.62; P < .001). Arterial graft, side-to-side anastomosis, higher graft flow, and antiplatelet therapy at discharge were associated with chronic total occlusion graft patency. The presence of 1 or more chronic total occlusions was not significantly associated with long-term composite of death, myocardial infarction, or repeat revascularization (adjusted hazard ratio, 0.91; 95% confidence interval, 0.54-1.51; P = .707). CONCLUSIONS: Chronic total occlusion graft was associated with an increased risk of graft failure. Surgical technique and guideline-directed medical therapy should be noted to improve chronic total occlusion graft patency.


Assuntos
Ponte de Artéria Coronária , Oclusão de Enxerto Vascular/epidemiologia , Idoso , Estudos de Coortes , Angiografia por Tomografia Computadorizada , Feminino , Seguimentos , Oclusão de Enxerto Vascular/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
10.
Clin Hemorheol Microcirc ; 80(1): 25-35, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33185589

RESUMO

BACKGROUND: Molecular targeted contrast-enhanced ultrasound (CEUS) imaging is a potential imaging strategy to improve the diagnostic accuracy of conventional ultrasound (US) imaging. US contrast agents are usually micrometer-sized and non-target gas bubbles while nano-sized and targeted agents containing phase-shift materials absorb more attractions for their size and the liquid core and excellent molecular imaging effect. METHODS: PLGA12k-mPEG2k-NH2, DSPE-mPEG2k and perfluorohexan (PFH) were used to construct a new targeted ultrasound contrast agent with CUB domain-containing protein 1 (CDCP1) receptor for the detection and diagnosis of prostate cancer. The potential of tumor-targeted nanoparticles (CDCP1-targeted perfluorohexan-loaded phase-transitional nanoparticles, anti-CDCP1 NPs) as contrast agents for ultrasound (US) imaging was assessed in vitro. Moreover, studies on the cytotoxicity and the targeting ability of anti-CDCP1 NPs assisted by US were carried out. RESULTS: The results showed that anti-CDCP1 NPs had low cytotoxicity, and with the increasing of polymer concentration in anti-CDCP1 NPs, the CEUS imaging of agent gradually enhanced, and enhanced imaging associated with the length of observing time. Furthermore, it was testified that anti-CDCP1 assisted the agent to target cells expressing CDCP1, which demonstrated the active targeting of anti-CDCP1 NPs in vitro. CONCLUSION: All in all, the feasibility of using targeted anti-CDCP1 NPs to enhance ultrasound imaging has been demonstrated in vitro, which laid a solid foundation for molecular US imaging in vivo, and anti-CDCP1 NPs might have a great clinical application prospect.


Assuntos
Nanopartículas , Linhagem Celular Tumoral , Meios de Contraste , Humanos , Masculino , Imagem Molecular , Ultrassonografia
11.
ACS Appl Mater Interfaces ; 13(28): 32763-32779, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34235912

RESUMO

Due to a special pathological type of triple-negative breast cancer (TNBC) and the lack of expression of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (Her 2), targeted therapies are not effective. The lack of effective treatment drugs and insensitivity to the current single-treatment methods are the biggest problems that we face with the TNBC treatment. Therefore, new strategies to achieve selective treatment and further visual efficacy evaluation will be powerful tools against TNBC. Herein, a novel tumor-targeted nanosized ultrasound contrast nanobubble loaded with chlorin e6 (Ce6), metformin (MET), and perfluorohexane (PFH) and covalently connected to the anti-PD-L1 peptide (DPPA-1) in the outer shell was fabricated. When accumulated in acidic tumor tissues, poly(ethylene glycol) (PEG) ligands detach, and DPPA-1 is exposed for programmed death-ligand 1 (PD-L1) targeting and blocking. The released metformin can relieve hypoxia by inhibiting mitochondrial complex I in the tumor microenvironment (TME) and enhance the therapeutic efficacy of Ce6 while synergizing with DPPA-1 by reducing PD-L1 expression. More significantly, photodynamic therapy (PDT) using multifunctional tumor-targeted nanosized ultrasound contrast agents (PD-L1-targeted pH-sensitive chlorin e6 (Ce6) and metformin (MET) drug-loaded phase transitional nanoparticles (Ce6/MET NPs-DPPA-1)) combined with PD-L1 checkpoint blocking can not only reduce tumor-mediated immunosuppression but also produce strong antitumor immunity. This finding provides a new idea for constructing multifunctional TNBC therapeutic nanoagents.


Assuntos
Meios de Contraste/química , Inibidores de Checkpoint Imunológico/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Animais , Antígeno B7-H1/metabolismo , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Clorofilídeos , Fluorocarbonos/química , Concentração de Íons de Hidrogênio , Inibidores de Checkpoint Imunológico/química , Luz , Metformina/química , Metformina/uso terapêutico , Camundongos , Nanopartículas/química , Peptídeos/química , Peptídeos/uso terapêutico , Técnicas Fotoacústicas , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Porfirinas/química , Porfirinas/efeitos da radiação , Porfirinas/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Ondas Ultrassônicas
12.
Adv Sci (Weinh) ; 8(11): e2003558, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34105277

RESUMO

The binding of amyloid precursor protein (APP) expressed on tumor cells to death receptor 6 (DR6) could initiate the necroptosis pathway, which leads to necroptotic cell death of vascular endothelial cells (ECs) and results in tumor cells (TCs) extravasation and metastasis. This study reports the first inhibitor of DR6/APP interaction as a novel class of anti-hematogenous metastatic agent. By rationally utilizing three combined strategies including selection based on phage display library, d-retro-inverso modification, and multiple conjugation of screened peptidomimetic with 4-arm PEG, the polymer-peptidomimetic conjugate PEG-tAHP-DRI (tetra-(D-retro-inverso isomer of AHP-12) substitued 4-arm PEG5k ) is obtained as the most promising agent with the strongest binding potency (KD  = 51.12 × 10-9  m) and excellent pharmacokinetic properties. Importantly, PEG-tAHP-DRI provides efficient protection against TC-induced ECs necroptosis both in vitro and in vivo. Moreover, this ligand exhibits prominent anti-hematogenous metastatic activity in serval different metastatic mouse models (B16F10, 4T1, CT26, and spontaneous lung metastasis of 4T1 orthotopic tumor model) and displays no apparent detrimental effects in preliminary safety evaluation. Collectively, this study demonstrates the feasibility of exploiting DR6/APP interaction to regulate hematogenous tumor cells transendothelial migration and provides PEG-tAHP-DRI as a novel and promising inhibitor of DR6/APP interaction for developments of anti-hematogenous metastatic therapies.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Comunicação Celular/efeitos dos fármacos , Neoplasias Hematológicas/tratamento farmacológico , Peptidomiméticos/farmacologia , Receptores do Fator de Necrose Tumoral/genética , Precursor de Proteína beta-Amiloide/antagonistas & inibidores , Animais , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Humanos , Ligantes , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/genética , Melanoma Experimental/patologia , Camundongos , Metástase Neoplásica , Peptidomiméticos/química , Receptores do Fator de Necrose Tumoral/antagonistas & inibidores , Migração Transendotelial e Transepitelial/efeitos dos fármacos , Migração Transendotelial e Transepitelial/genética
13.
ACS Appl Mater Interfaces ; 13(12): 13990-14003, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33739080

RESUMO

Paclitaxel (PTX) is a first-line chemotherapeutic agent to treat prostate cancer (PCa), but a large number of patients acquired drug resistance after short-term treatment. To develop combinational therapeutics to overcome PTX-resistant PCa, we established PTX-resistant LNCaP (LNCaP/PTX) cells and found that the LNCaP/PTX cells exhibited epithelial-mesenchymal transition (EMT) and enhanced metastasis during the selection process. We revealed that ß-tubulin III, androgen receptor, and CXCR4 expressions were significantly increased in LNCaP/PTX cells and directly contributed to PTX resistance and EMT. Therefore, we developed prostate-specific membrane antigen aptamer (Apt)-functionalized shell-core nanoparticles (PTX/siRNAs NPs-Apt); the hydrophobic DSPE encapsulating PTX formed the dense inner core and the hydrophilic Apt-PEG2K with calcium phosphate (CaP) absorbing siRNAs formed the outer shell to sequentially release siRNAs and PTX, where CaP could trigger lysosomal escape to ensure that pooled siRNAs efficiently released into the cytoplasm to reverse EMT and resensitize PTX, while the PTX located in the core was subsequently released to exert the killing effect of chemotherapy to achieve the best synergistic effect. PTX/siRNAs NPs-Apt showed an enhanced tumor-targeting ability and achieved superior efficacy in the subcutaneous and orthotopic PCa tumor model with minimal side effects.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Paclitaxel/administração & dosagem , Neoplasias da Próstata/terapia , RNA Interferente Pequeno/administração & dosagem , Animais , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Portadores de Fármacos/química , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Paclitaxel/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , RNA Interferente Pequeno/farmacologia , Terapêutica com RNAi
14.
Biomaterials ; 269: 120478, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33213862

RESUMO

Cisplatin (Pt(II)) resistance is an important factor in the high mortality rates of ovarian cancer. Herein, we synthesized multifunctional tumor-targeted poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs-cRGD) for monitoring therapeutic effects by dual-mode imaging and overcoming cisplatin resistance. Uniformly sized NPs-cRGD demonstrated controlled and sustained release of drugs and genes, excellent gene loading and gene protection capacity, good storage stability and no serum-induced aggregation in vitro. NPs-cRGD demonstrated clear, targeting and prolonged ultrasound imaging and magnetic resonance imaging (MRI) in vivo. The targeting of NPs-cRGD combined with ultrasound facilitated nanoparticle penetrattion into cells; entry was time-dependent. NPs-cRGD escaped from lysosomes, thereby preventing siBIRC5 degradation, which enabled siBIRC5 to efficiently inhibit the antiapoptosis effects of BIRC5 in SKO3-DDP to overcome the antiapoptosis properties of resistant cells. Furthermore, Pt(IV) in NPs-cRGD exhausted glutathione (GSH), thereby increasing drug accumulation to effectively increase Pt(II) levels. The subsequent combination of Pt(II) with DNA prevented the expressions of genes and upregulated the expression of p53 to induce the mitochondria apoptosis pathway. The reduced GSH activity and the generation of Pt(II) further promoted high levels of reactive oxygen species (ROS) to induce cell apoptosis. Therefore, NPs-cRGD with ultrasound promoted the apoptosis of resistant ovarian cancer cells by multiple mechanisms, including increased cellular drug accumulation, reversed antiapoptotic effects by siBIRC5, and enhanced ROS levels. In a tumor-bearing nude mice model, NPs-cRGD with US demonstrated excellent tumor-targeting, high efficiency tumor inhibition and low systemic toxicity. Therefore, NPs-cRGD provides a means to monitor treatment processes and can be combined with ultrasound treatment to overcome ovarian cancer resistance in vitro and in vivo.


Assuntos
Nanopartículas Multifuncionais , Nanopartículas , Neoplasias Ovarianas , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Imageamento por Ressonância Magnética , Camundongos , Camundongos Nus , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/tratamento farmacológico
15.
Adv Sci (Weinh) ; 7(22): 1902989, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33240749

RESUMO

As a profitable product from CO2 electroreduction, HCOOH holds economic viability only when the selectivity is higher than 90% with current density (j) over -200.0 mA cm-2. Herein, Bi@Sn core-shell nanoparticles (Bi core and Sn shell, denoted as Bi@Sn NPs) are developed to boost the activity and selectivity of CO2 electroreduction into HCOOH. In an H-cell system with 0.5 m KHCO3 as electrolyte, Bi@Sn NPs exhibit a Faradaic efficiency for HCOOH (FEHCOOH) of 91% with partial j for HCOOH (j HCOOH) of -31.0 mA cm-2 at -1.1 V versus reversible hydrogen electrode. The potential application of Bi@Sn NPs is testified via chronopotentiometric measurements in the flow-cell system with 2.0 m KHCO3 electrolyte. Under this circumstance, Bi@Sn NPs achieve an FEHCOOH of 92% with an energy efficiency of 56% at steady-state j of -250.0 mA cm-2. Theoretical studies indicate that the energy barrier of the potential-limiting step for the formation of HCOOH is decreased owing to the compressive strain in the Sn shell, resulting in the enhanced catalytic performance.

16.
ChemSusChem ; 13(23): 6307-6311, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32755063

RESUMO

Single atoms have been widely applied as efficient catalysts in various catalytic systems due to its high selectivity for certain products, which is induced by a uniform coordinate environment of active sites. Herein, it is demonstrated that Bi single atoms anchored on carbon black (Bi SAs/C) can serve as an efficient catalyst for CO2 electroreduction into formate (HCOO- ). During CO2 electroreduction, Bi SAs/C achieved a faradaic efficiency for HCOO- of 83.6 % at-1.1 Vversus reversible hydrogen electrode (V vs. RHE). Notably, the selectivity for HCOO- of Bi SAs/C was always higher than 95 % at all applied potentials. In addition, at-1.2 Vvs.RHE, the current density for HCOO- formation in thepresence of Bi SAs/C reached-12.0 mA cm-2 , which was 3.4 times as high as that (-3.5 mA cm-2 ) of BiOx clusters on carbon black (BiOx /C). Mechanistic studies revealed that Bi SAs/C facilitated the faradaic process and accelerated reaction kinetics in comparison with BiOx /C.

17.
Chin J Physiol ; 59(2): 119-25, 2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27080467

RESUMO

Gamma-aminobutyric acid (GABA) is involved in the proliferation, differentiation, and migration of several cell types including cancer cells. Whether GABA may be involved with acute lymphoblastic leukemia (ALL) is unclear. Therefore, the goal of this report was to examine if GABAergic signaling expression is altered in bone marrow lymphocytes of ALL children. RT-PCR and western blot analysis were used to examine the expression of the GABA synthetizing enzyme glutamic acid decarboxylase (GAD) isoforms (GAD65 and GAD67), and type-A GABA receptor (GABAAR) subunits [α(1-6), ß(1-3), γ(1-3), δ, ε, θ, π, and ρ(1-3)] in bone marrow lymphocytes of 19 ALL children before chemotherapy. The data obtained were compared with those in 13 age-matched non-ALL children. Immunofluorescent staining was used to examine the cellular localization of GAD. We found that GAD and GABAAR subunits were expressed in bone marrow lymphocytes of ALL children. Moreover, RT-PCR and western blot showed that GAD and several GABAAR subunits were significantly increased in ALL children as compared with the data of non-ALL children. Our present study reveals up-regulation of GABAergic signaling events in bone marrow lymphocytes in ALL children. However, the role of this signaling system in lymphocyte proliferation and invasion as related to the progression of ALL requires further investigation.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Ácido gama-Aminobutírico/metabolismo , Western Blotting , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Glutamato Descarboxilase/biossíntese , Glutamato Descarboxilase/genética , Humanos , Isoenzimas/biossíntese , Isoenzimas/genética , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimologia , Receptores de GABA-A/biossíntese , Receptores de GABA-A/genética , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Ácido gama-Aminobutírico/biossíntese
18.
Toxicology ; 326: 44-52, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25456265

RESUMO

Alcohol overindulgence is a risk factor of type 2 diabetes mellitus. However, the mechanisms by which alcohol overindulgence damages glucose metabolism remain unclear. Pancreatic islet ß-cells are endowed with type-A γ-aminobutyric acid receptor (GABAAR) mediated autocrine signaling mechanism, which regulates insulin secretion and fine-tunes glucose metabolism. In neurons GABAAR is one of the major targets for alcohol. This study investigated whether ethanol alters glucose metabolism by affecting GABAAR signaling in pancreatic ß-cells. Blood glucose level of test mice was measured using a blood glucose meter. Insulin secretion by the pancreatic ß-cell line INS-1 cells was examined using a specific insulin ELISA kit. Whole-cell patch-clamp recording was used to evaluate GABA-elicited current in INS-1 cells. Western blot and immunostaining were used to measure the expression of GABAAR subunits in mouse pancreatic tissues or in INS-1 cells. Intraperitoneal (i.p.) administration of ethanol (3.0g/kg body weight) to mice altered glucose metabolism, which was associated with decreased expression of GABAAR α1- and δ- subunits on the surface of pancreatic ß-cells. Acute treatment of cultured INS-1cells with ethanol (60mM) decreased the GABA-induced current and reduced insulin secretion. In contrast, treating INS-1 cells with GABA (100µM) largely prevented the ethanol-induced reduction of insulin release. Importantly, pre-treating mice with GABA (i.p., 1.5mg/kg body weight) partially reversed ethanol-induced impairment of glucose homeostasis in mice. Our data suggest a novel role of pancreatic GABA signaling in protecting pancreatic islet ß-cells from ethanol-induced dysfunction.


Assuntos
Glicemia/efeitos dos fármacos , Etanol/toxicidade , Agonistas de Receptores de GABA-A/farmacologia , Antagonistas de Receptores de GABA-A/toxicidade , Células Secretoras de Insulina/efeitos dos fármacos , Receptores de GABA-A/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ácido gama-Aminobutírico/farmacologia , Animais , Glicemia/metabolismo , Linhagem Celular , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Masculino , Potenciais da Membrana , Camundongos , Ratos , Receptores de GABA-A/metabolismo , Fatores de Tempo
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