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1.
Mol Pharm ; 20(6): 2822-2835, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37134112

RESUMO

Progesterone (PR) is an endogenous steroid hormone that activates the progesterone receptor (PgR) and is known to play a critical role in cancer progression. Herein, we report the development of cationic lipid-conjugated PR derivatives by covalently conjugating progesterone with cationic lipids of varying hydrocarbon chain lengths (n = 6-18) through a succinate linker. Cytotoxicity studies performed on eight different cancer cell lines reveal that PR10, one of the lead derivatives, exerts notable toxicity (IC50 = 4-12 µM) in cancer cells irrespective of their PgR expression status and remains largely nontoxic to noncancerous cells. Mechanistic studies show that PR10 induces G2/M-phase cell cycle arrest in cancer cells, leading to apoptosis and cell death by inhibiting the PI3K/AKT cell survival pathway and p53 upregulation. Further, in vivo study shows that PR10 treatment significantly reduces melanoma tumor growth and prolongs the overall survival of melanoma tumor-bearing C57BL/6J mice. Interestingly, PR10 readily forms stable self-aggregates of ∼190 nm size in an aqueous environment and exhibits selective uptake into cancerous cell lines. In vitro uptake mechanism studies in various cell lines (cancerous cell lines B16F10, MCF7, PC3, and noncancerous cell line HEK293) using endocytosis inhibition proves that PR10 nanoaggregates enter selectively into the cancer cells predominantly using macropinocytosis and/or caveolae-mediated endocytosis. Overall, this study highlights the development of a self-aggregating cationic derivative of progesterone with anticancer activity, and its cancer cell-selective accumulation in nanoaggregate form holds great potential in the field of targeted drug delivery.


Assuntos
Melanoma , Progesterona , Camundongos , Animais , Humanos , Progesterona/farmacologia , Linhagem Celular Tumoral , Fosfatidilinositol 3-Quinases/metabolismo , Células HEK293 , Camundongos Endogâmicos C57BL , Apoptose , Melanoma/tratamento farmacológico , Lipídeos/farmacologia , Proliferação de Células
2.
Langmuir ; 39(11): 4071-4081, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36905363

RESUMO

Exploring a covalent organic framework (COF) material as an efficient metal-free photocatalyst and as an adsorbent for the removal of pollutants from contaminated water is very challenging in the context of sustainable chemistry. Herein, we report a new porous crystalline COF, C6-TRZ-TPA COF, via segregation of donor-acceptor moieties through the extended Schiff base condensation between tris(4-formylphenyl)amine and 4,4',4″-(1,3,5-triazine-2,4,6-triyl)trianiline. This COF displayed a Brunauer-Emmett-Teller (BET) surface area of 1058 m2 g-1 with a pore volume of 0.73 cc g-1. Again, extended π-conjugation, the presence of heteroatoms throughout the framework, and a narrow band gap of 2.2 eV, all these features collectively work for the environmental remediation in two different perspectives: it could harness solar energy for environmental clean-up, where the COF has been explored as a robust metal-free photocatalyst for wastewater treatment and as an adsorbent for iodine capture. In our endeavor of wastewater treatment, we have conducted the photodegradation of rose bengal (RB) and methylene blue (MB) as model pollutants since these are extremely toxic, are health hazard, and bioaccumulative in nature. The catalyst C6-TRZ-TPA COF showed a very high catalytic efficiency of 99% towards the degradation of 250 parts per million (ppm) of RB solution in 80 min under visible light irradiation with the rate constant of 0.05 min-1. Further, C6-TRZ-TPA COF is found to be an excellent adsorbent as it efficiently adsorbed radioactive iodine from its solution as well as from the vapor phase. The material exhibits a very rapid iodine capturing tendency with an outstanding iodine vapor uptake capacity of 4832 mg g-1.

3.
Cell Biol Toxicol ; 34(2): 125-142, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28914393

RESUMO

Costunolide (CE) is a sesquiterpene lactone well-known for its antihepatotoxic, antiulcer, and anticancer activities. The present study focused on the evaluation of the cytogenetic toxicity and cellular death-inducing potential of CE in CHO cells, an epithelial cell line derived from normal ovary cells of Chinese hamster. The cytotoxic effect denoting MTT assay has shown an IC50 value of 7.56 µM CE, where 50% proliferation inhibition occurs. The oxidative stress caused by CE was confirmed based on GSH depletion induced cell death, conspicuously absent in N-acetylcysteine (GSH precursor) pretreated cells. The evaluation of genotoxic effects of CE using cytokinesis block micronucleus assay and chromosomal aberration test has shown prominent induction of binucleated micronucleated cells and aberrant metaphases bearing chromatid and chromosomal breaks, indicating CE's clastogenic and aneugenic potential. The apoptotic death in CE treated cells was confirmed by an increase in the number of cells in subG1 phase, exhibiting chromatin condensation and membranous phosphatidylserine translocation. The apoptosis induction follows mitochondrial mediation, evident from an increase in the BAX/Bcl-2 ratio, caspase-3/7 activity, and mitochondrial membrane permeability. CE also induces cytostasis in addition to apoptosis, substantiated by the reduced cytokinetic (replicative indices) and mitotic (mitotic indices and histone H3 Ser-10 phosphorylation) activities. Overall, the cellular GSH depletion and potential genotoxic effects by CE led the CHO cells to commit apoptosis and lowered cell division. The observed sensitivity of CHO cells doubts unintended adverse effects of CE on normal healthy cells, suggesting higher essentiality of further studies in order to establish its safety efficacy in therapeutic explorations.


Assuntos
Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sesquiterpenos/toxicidade , Animais , Células CHO , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Células Epiteliais/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Saussurea/química , Sesquiterpenos/isolamento & purificação
4.
Mol Cell Biochem ; 436(1-2): 119-136, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28585089

RESUMO

Glucocorticoid, such as dexamethasone (Dex) is often used along with chemotherapy to antagonize side effects of chemotherapy. However, sustained use of Dex frequently develops drug resistance in patients. As a strategy to re-induce drug sensitivity, we planned to modify Dex by chemically conjugating it with twin ten carbon aliphatic chain containing cationic lipid. The resultant molecule, DX10, inhibited STAT3 activation through lowering the production of IL-6. To enhance the STAT3 inhibitory effect of DX10, we used WP (a commercially available STAT3 inhibitor) along with DX10. Combination treatment of both significantly inhibited STAT3 activation when compared to either of the individual treatment. The effect of DX10, either in combination or alone, was mediated through glucocorticoid receptor (GR), thereby repurposing the role of GR in the context of p-STAT3 inhibition-mediated cancer treatment. Cellular viability study proved the synergistic effect of WP and DX10. Further, combination treatment led to induction of early stage of apoptosis and cell cycle arrest. In vivo melanoma tumor regression study confirmed the enhanced anti-tumor activity of co-treatment over individual treatment of DX10 or WP. Thus, together our result demonstrates that DX10 may be used in combination therapy with STAT3 inhibitor like WP for combating cancer with constitutively active STAT3.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Melanoma/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Fator de Transcrição STAT3/antagonistas & inibidores , Células A549 , Animais , Células CHO , Ensaios Clínicos Fase I como Assunto , Cricetulus , Dexametasona/análogos & derivados , Dexametasona/farmacologia , Humanos , Células MCF-7 , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Células NIH 3T3 , Proteínas de Neoplasias/metabolismo , Piridinas/farmacologia , Tirfostinas/farmacologia
5.
Mol Pharm ; 13(3): 1081-8, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26832839

RESUMO

The objective of the present study is to develop a liposomal formulation for delivering anticancer drug to breast cancer stem-cell-like cells, ANV-1, and evaluate its pharmacokinetics in an animal model. The anticancer drug ESC8 was used in dexamethasone (Dex)-associated liposome (DX) to form ESC8-entrapped liposome named DXE. ANV-1 cells showed high-level expression of NRP-1. To enhance tumor regression, we additionally adapted to codeliver the NRP-1 shRNA-encoded plasmid using the established DXE liposome. In vivo efficacy of DXE-NRP-1 was carried out in mice bearing ANV-1 cells as xenograft tumors and the extent of tumor growth inhibition was evaluated by tumor-size measurement. A significant difference in tumor volume started to reveal between DXE-NRP-1 group and DXE-Control group. DXE-NRP-1 group showed ∼4 folds and ∼2.5 folds smaller tumor volume than exhibited by untreated and DXE-Control-treated groups, respectively. DXE disposition was evaluated in Sprague-Dawley rats following an intraperitoneal dose (3.67 mg/kg of ESC8 in DXE). The plasma concentrations of ESC8 in the DXE formulation were measured by liquid chromatography mass spectrometry and pharmacokinetic parameters were determined using a noncompartmental analysis. ESC8 had a half-life of 11.01 ± 0.29 h, clearance of 2.10 ± 3.63 L/kg/h, and volume of distribution of 33.42 ± 0.83 L/kg. This suggests that the DXE liposome formulation could be administered once or twice daily for therapeutic efficacy. In overall, we developed a potent liposomal formulation with favorable pharmacokinetic and tumor regressing profile that could sensitize and kill highly aggressive and drug-resistive cancer stem-cell-like cells.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Lipossomos/química , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Composição de Medicamentos , Transição Epitelial-Mesenquimal , Feminino , Humanos , Masculino , Camundongos , Células-Tronco Neoplásicas/metabolismo , Neuropilina-1/antagonistas & inibidores , Neuropilina-1/genética , RNA Interferente Pequeno/genética , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
6.
Mol Pharm ; 13(7): 2507-23, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-27184196

RESUMO

Many cancers including the late stage ones become drug-resistant and undergo epithelial-to-mesenchymal transition (EMT). These lead to enhanced invasion, migration, and metastasis toward manifesting its aggressiveness and malignancy. One of the key hallmarks of cancer is its overdependence on glycolysis as its preferred energy metabolism pathway. The strict avoidance of alternate energy pathway gluconeogenesis by cancer cells points to a yet-to-be hoisted role of glucocorticoid receptor (GR) especially in tumor microenvironment, where cells are known to become drug-sensitive through induction of gluconeogenesis. However, since GR is involved in metabolism, anti-inflammatory reactions, immunity besides inducing gluconeogenesis, a greater role of GR in tumor microenvironment is envisaged. We have shown previously that GR, although ubiquitously expressed in all cells; afford to be an effective cytoplasmic target for killing cancer cells selectively. Herein, we report the therapeutic use of a newly developed GR-targeted liposomal concoction (DXE) coformulating a lipophilic drug (ESC8) and an anti-Hsp90 anticancer gene against aggressive tumor models. This induced drug-sensitivity and apoptosis while reversing EMT in tumor cells toward effective retardation of aggressive growth in pancreas and skin tumor models. Additionally, the ESC8-free lipid formulation upon cotreatment with hydrophilic drugs, gemcitabine and doxorubicin, could effectively sensitize and kill pancreatic cancer and melanoma cells, respectively. The formulation-triggered EMT-reversal was GR-dependent. Overall, we found a new strategy for drug sensitization that led to the advent of new GR-targeted anticancer therapeutics.


Assuntos
Transição Epitelial-Mesenquimal/fisiologia , Proteínas de Choque Térmico HSP90/metabolismo , Lipossomos/química , Receptores de Glucocorticoides/metabolismo , Animais , Células COS , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , DNA/química , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Transição Epitelial-Mesenquimal/genética , Proteínas de Choque Térmico HSP90/genética , Humanos , Lipossomos/administração & dosagem , Camundongos , Reação em Cadeia da Polimerase , Receptores de Glucocorticoides/genética , Gencitabina
7.
Biomed Chromatogr ; 30(12): 2024-2030, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27306429

RESUMO

A lipid-conjugated, estrogenic derivative molecule, ESC8, compared with other estrogenic molecules, encourages cell death in both ER-positive and ER-negative breast cancer cells. A rapid and highly sensitive assay method has been developed and validated for the estimation of a ESC8 in rat plasma using liquid chromatography coupled with mass spectrometry under positive-ion mode with electrospray ionization. The sample process includes using methanol for precipitation of ESC8 and dextromethorphan (internal standard, IS) from plasma. Chromatographic separation was achieved with methanol-water-formic acid (70:30:0.1% v/v/v) pumped at a flow rate of 0.3mL/min and a C18 column (50 × 2.1 mm i.d., 1.7 µm particle size) with a total run time of 5 min. The m/z ions monitored were 568.5 and 272.1 for ESC8 and IS, respectively. The lower limit of quantitation achieved was 1.08 ng/mL and linearity was observed from 5 to 500 ng/mL. The intra- and inter-day precisions were <4%. The proposed method was successfully applied to a preliminary pharmacokinetic study of ESC8 liposomal formulation following an intraperitoneal administration of 3.67 mg/kg in rats. The concentrations of ESC8 in plasma were quantifiable up to 36 h. The peak concentration of ESC8 was found to be 110.72 ng/mL, the area under the concentration-time curve was 1625.23ng/mL h and the half-life was 11.72 h.


Assuntos
Cromatografia Líquida/métodos , Estrogênios/sangue , Lipídeos/química , Espectrometria de Massas/métodos , Animais , Calibragem , Estrogênios/farmacocinética , Limite de Detecção , Ratos , Padrões de Referência , Reprodutibilidade dos Testes
8.
Nanomaterials (Basel) ; 14(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38334590

RESUMO

Approximately 10% of women suffer from endometriosis during their reproductive years. This disease is a chronic debilitating condition whose etiology for lesion implantation and survival heavily relies on adhesion and angiogenic factors. Currently, there are no clinically approved agents for its detection. In this study, we evaluated cRGD-peptide-conjugated nanoparticles (RGD-Cy5.5-MN) to detect lesions using magnetic resonance imaging (MRI) in a mouse model of endometriosis. We utilized a luciferase-expressing murine suture model of endometriosis. Imaging was performed before and after 24 h following the intravenous injection of RGD-Cy5.5-MN or control nanoparticles (Cy5.5-MN). Next, we performed biodistribution of RGD-Cy5.5-MN and correlative fluorescence microscopy of lesions stained for CD34. Tissue iron content was determined using inductively coupled plasma optical emission spectrometry (ICP-OES). Our results demonstrated that targeting endometriotic lesions with RGD-Cy5.5-MN resulted in a significantly higher delta T2* upon its accumulation compared to Cy5.5-MN. ICP-OES showed significantly higher iron content in the lesions of the animals in the experimental group compared to the lesions of the animals in the control group. Histology showed colocalization of Cy5.5 signal from RGD-Cy5.5-MN with CD34 in the lesions pointing to the targeted nature of the probe. This work offers initial proof-of-concept for targeting angiogenesis in endometriosis which can be useful for potential clinical diagnostic and therapeutic approaches for treating this disease.

9.
Chem Asian J ; 18(2): e202201136, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36482874

RESUMO

Paclitaxel (PTX) is a widely used chemotherapeutic agent in the clinic. However, its clinical benefit is limited due to its low water solubility, off-target toxicity, and for being a multidrug-resistant (MDR) substrate. To overcome these limitations in this study, a tumor-targeting peptide (CRGDK peptide, a ligand for NRP-1 receptor) conjugate of α-tocopheryl succinate (α-TOS) was synthesized and modified on PTX-loaded lipid aggregate (TL-PTX) to leverage the benefits of α-TOS, which include a) anti-cancer activity, b) increased PTX loading, and c) inhibition of MDR activity. Use of peptide conjugate of α-TOS (α-TOS-CRGDK) in lipid aggregate increased PTX entrapment efficiency by 20%, helped in NRP-1 specific cellular uptake and significantly enhanced apoptotic and cell killing activity (p <0.01) of PTX compared to control formulation (CL-PTX) by inhibiting MDR-activity in melanoma resulting in ∼70% increment in overall survival of melanoma tumor-bearing mice. In conclusion, CRGDK- α-TOS conjugate in association with PTX-loaded liposome provided a unique NRP-1 targeted, drug-resistant reversing anticancer regimen for treating aggressive melanoma.


Assuntos
Melanoma , Paclitaxel , Camundongos , Animais , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , alfa-Tocoferol/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Peptídeos/farmacologia , Lipídeos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos
10.
Commun Biol ; 6(1): 815, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542121

RESUMO

Small extracellular vesicles (sEV) in TNBC patients' plasma promote T cell dysfunction and tumor progression. Here we show that tumor cell-derived exosomes (TEX) carrying surface PDL-1, PD-1, Fas, FasL, TRAIL, CTLA-4 and TGF-ß1 induce apoptosis of CD8+T and CD4+T cells but spare B and NK cells. Inhibitors blocking TEX-induce receptor/ligand signals and TEX pretreatments with proteinase K or heat fail to prevent T cell apoptosis. Cytochalasin D, Dynosore or Pit Stop 2, partly inhibit TEX uptake but do not prevent T cell apoptosis. TEX entry into T cells induces cytochrome C and Smac release from mitochondria and caspase-3 and PARP cleavage in the cytosol. Expression of survival proteins is reduced in T cells undergoing apoptosis. Independently of external death receptor signaling, TEX entry into T cells induces mitochondrial stress, initiating relentless intrinsic apoptosis, which is responsible for death of activated T cells in the tumor-bearing hosts. The abundance of TEX in cancer plasma represents a danger for adoptively transferred T cells, limiting their therapeutic potential.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Caspases/metabolismo , Apoptose , Proteínas Reguladoras de Apoptose , Linfócitos T/metabolismo
11.
Front Mol Biosci ; 10: 1179343, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37398551

RESUMO

Introduction: Recent studies have shown that miRNA-10b is highly expressed in high-grade glioblastoma multiforme (GBM), and its inhibition leads to deregulation of multiple pathways in tumorigenesis, resulting in repression of tumor growth and increased apoptosis. Thus, we hypothesized that suppressing miR-10b could enhance the cytotoxicity of conventional GBM chemotherapy with temozolomide (TMZ). Methods: Inhibition of miR-10b in glioblastoma cells was achieved using an experimental therapeutic consisting of anti-miR10b antagomirs conjugated to iron oxide nanoparticles (termed MN-anti-miR10b). The nanoparticles serve as delivery vehicles for the antagomirs as well as imaging reporters guiding the delivery in future animal studies. Results: Treatment of U251 and LN229 human glioblastoma cells with MN-anti-miR10b led to inhibition of miR-10b accompanied by repression of growth and increase in apoptosis. We next explored whether MN-anti-miR10b could enhance the cytotoxic effect of TMZ. During these studies, we unexpectedly found that TMZ monotherapy increased miR-10b expression and changed the expression of corresponding miR-10b targets. This discovery led to the design of a sequence-dependent combination treatment, in which miR-10b inhibition and induction of apoptosis by MN-anti-miR10b was followed by a sub-therapeutic dose of TMZ, which caused cell cycle arrest and ultimately cell death. This combination was highly successful in significant enhancement of apoptosis and decrease in cell migration and invasiveness. Discussion: Considering the unexpected effects of TMZ on miR-10b expression and possible implications on its clinical application, we reasoned that comprehensive in vitro studies were warranted before embarking on studies in animals. These intriguing findings serve as a solid foundation for future in vivo studies and offer promise for the successful treatment of GBM.

12.
Cells ; 11(12)2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35741093

RESUMO

Exosomes that are released by T cells are key messengers involved in immune regulation. However, the molecular profiling of these vesicles, which is necessary for understanding their functions, requires their isolation from a very heterogeneous mixture of extracellular vesicles that are present in the human plasma. It has been shown that exosomes that are produced by T cells could be isolated from plasma by immune capture using antibodies that target the CD3 antigen, which is a key component of the TCR complex that is present in all T lymphocytes. Here, we demonstrate that CD3(+) exosomes that are isolated from plasma can be used for high-throughput molecular profiling using proteomics and metabolomics tools. This profiling allowed for the identification of proteins and metabolites that differentiated the CD3(+) from the CD3(-) exosome fractions that were present in the plasma of healthy donors. Importantly, the proteins and metabolites that accumulated in the CD3(+) vesicles reflected the known molecular features of T lymphocytes. Hence, CD3(+) exosomes that are isolated from human plasma by immune capture could serve as a "T cell biopsy".


Assuntos
Exossomos , Complexo CD3/metabolismo , Exossomos/metabolismo , Humanos , Metabolômica , Proteínas/metabolismo , Proteômica , Linfócitos T
13.
ACS Appl Mater Interfaces ; 14(1): 771-783, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34962379

RESUMO

The main component of natural gas is methane, whose combustion contributes to global warming. As such, sustainable, energy-efficient, nonfossil-based methane production is needed to satisfy current energy demands and chemical feedstocks. In this article, we have constructed a metal-free porous polyketone (TPA-DPA PPK) with donor-acceptor (D-A) groups with an extensive π-conjugation by facile Friedel-Crafts acylation reaction between triphenylamine (TPA) and pyridine-2,6-dicarbonyl dichloride (DPA). TPA-DPA PPK is a metal-free catalyst for visible-light-driven CO2 photoreduction to CH4, which can be used as a solar fuel in the absence of any cocatalyst and sacrificial agent. CH4 production (152.65 ppm g-1) is ∼5 times greater than that of g-C3N4 under the same test conditions. Charge-density difference plots from excited-state time-dependent density functional theory (TD-DFT) calculations indicate a depletion and accumulation of charge density among the donor/acceptor functional groups upon photoexcitation. Most notably, binding energies from DFT demonstrate that H2O is more strongly bound with the pyridinic nitrogen group than CO2, which shed insight into mechanistic pathways for photocatalytic CO2 reduction.

14.
ACS Appl Mater Interfaces ; 14(33): 37699-37708, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35960025

RESUMO

Designing an efficient catalyst for a sustainable photoelectrochemical water oxidation reaction is very challenging in the context of renewable energy research. Here, we have introduced a new semiconducting porous zinc-thiolate framework via successful stitching of an "N" donor linker with a triazine-based tristhiolate secondary building unit in the overall architecture. The introduction of both linker and tristhiolate ligand synergistically modifies the architecture by making it a rigid, crystalline, three-dimensional, thermally stable, and porous framework. Our novel zinc-thiolate framework is used as an n-type semiconductor as revealed from the solid-state UV-vis DRS spectroscopic analysis, ac and dc conductivity analysis, and Mott-Schottky plot. This n-type semiconductor-based zinc-thiolate framework is utilized in the photoelectrochemical water oxidation reaction. It displayed a very high efficiency for a visible-light-driven oxygen evolution reaction (OER) in a KOH medium using standard Ag/AgCl as the reference electrode. The superiority of this material was further revealed from the low onset potential (0.822 mV vs RHE), high photocurrent density (0.204 mA cm-2), good stability, and high O2 evolution rate (77 µmol g-1 of oxygen evolution within 2 h), and a good efficiency (ABPE 0.42%, IPCE 29.6% and APCE 34.5%). Furthermore, the porosity in the overall framework seems to be a blessing to the photoelectrochemical performance due to better mass diffusion of the electrolyte. A detailed mechanism for the OER reaction was analyzed through density functional theory analysis suggesting the potential future of this Zn-thiolate framework for achieving a high efficiency in the sustainable water oxidation reaction.

15.
Cell Death Dis ; 13(4): 371, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440572

RESUMO

Reactive astrocytes (RA) secrete lipocalin-2 (LCN2) glycoprotein that regulates diverse cellular processes including cell death/survival, inflammation, iron delivery and cell differentiation. Elevated levels of LCN2 are considered as a biomarker of brain injury, however, the underlying regulatory mechanisms of its expression and release are not well understood. In this study, we investigated the role of astrocytic Na+/H+ exchanger 1 (NHE1) in regulating reactive astrocyte LCN2 secretion and neurodegeneration after stroke. Astrocyte specific deletion of Nhe1 in Gfap-CreER+/-;Nhe1f/f mice reduced astrogliosis and astrocytic LCN2 and GFAP expression, which was associated with reduced loss of NeuN+ and GRP78+ neurons in stroke brains. In vitro ischemia in astrocyte cultures triggered a significant increase of secreted LCN2 in astrocytic exosomes, which caused neuronal cell death and neurodegeneration. Inhibition of NHE1 activity during in vitro ischemia with its potent inhibitor HOE642 significantly reduced astrocytic LCN2+ exosome secretion. In elucidating the cellular mechanisms, we found that stroke triggered activation of NADPH oxidase (NOX)-NF-κB signaling and ROS-mediated LCN2 expression. Inhibition of astrocytic NHE1 activity attenuated NOX signaling and LCN2-mediated neuronal apoptosis and neurite degeneration. Our findings demonstrate for the first time that RA use NOX signaling to stimulate LCN2 expression and secretion. Blocking astrocytic NHE1 activity is beneficial to reduce LCN2-mediated neurotoxicity after stroke.


Assuntos
Astrócitos , Lipocalina-2 , Acidente Vascular Cerebral , Animais , Astrócitos/metabolismo , Isquemia/metabolismo , Lipocalina-2/genética , Lipocalina-2/metabolismo , Camundongos , NADPH Oxidases/metabolismo , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo , Acidente Vascular Cerebral/metabolismo
16.
Melanoma Res ; 31(5): 472-475, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284459

RESUMO

Cancer liquid biopsy encompassing circulating tumor cells (CTC), circulating tumor DNA (ctDNA) and/or tumor-derived exosomes (TEX) emerges as a novel approach to early detection, noninvasive monitoring of responses to therapy and predicting patient survival. TEX are a key component of liquid biopsy because they mimic tumor cells in their proteomic and genetic content. Two recent proteomic analyses of TEX released into plasma by melanoma cells confirms the potential of TEX as diagnostic and prognostic markers in melanoma.


Assuntos
Biomarcadores Tumorais/sangue , Exossomos/patologia , Melanoma/patologia , Células Neoplásicas Circulantes/patologia , Proteoma/metabolismo , Progressão da Doença , Exossomos/metabolismo , Humanos , Melanoma/metabolismo , Células Neoplásicas Circulantes/metabolismo , Prognóstico , Proteoma/análise , Taxa de Sobrevida
17.
Methods Mol Biol ; 2265: 305-321, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704724

RESUMO

Tumor-derived exosomes (TEX), a subset of small extracellular vesicles (EVs) which originate from the endocytic compartment of tumor cells, are emerging as key players in cancer progression. TEX circulate freely in patients' body fluids and transfer bioactive cargos from tumor to various recipient cells. The molecular cargo of melanoma cell-derived exosomes (MTEX) mimics that of the tumor, and MTEX serve as a liquid biopsy that provides potentially useful information for cancer diagnosis, prognosis, or responses to therapy. Plasma of melanoma patients contains a mix of MTEX and exosomes produced by nonmalignant cells (NMTEX). Isolation of these exosome subtypes from the bulk of plasma exosomes is necessary to evaluate contributions of each as potential biomarkers of melanoma progression and outcome. Here, methods for separation of MTEX from T cell-derived exosomes from a single small volume of plasma and their subsequent molecular and functional characterization are described. Following size exclusion chromatography (SEC) to isolate total plasma exosomes, immune affinity-based capture of MTEX with anti-CSPG4 antibody and then of exosomes produced by T cells with anti-CD3 antibody is used to sequentially isolate the two subsets. This immune capture method enables the recovery of MTEX and CD3+ exosomes in quantities sufficient both for molecular profiling by flow cytometry or western blotting and for functional analyses.


Assuntos
Biomarcadores Tumorais/sangue , Western Blotting , Exossomos/metabolismo , Citometria de Fluxo , Melanoma/sangue , Linfócitos T/metabolismo , Cromatografia em Gel , Exossomos/patologia , Humanos , Biópsia Líquida , Plasma/metabolismo , Linfócitos T/patologia
18.
J Extracell Vesicles ; 10(4): e12063, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33613873

RESUMO

Molecular profiling of small extracellular vesicles (sEV) isolated from plasma of cancer patients emerges as promising strategy for biomarkers discovery. We investigated the proteomic profiles of sEV immunoselected using anti-CSPG4 antibodies from 15 melanoma patients' plasma. The proteomes of sEV separated into melanoma cell-derived (MTEX) and non-malignant cell-derived (NMTEX) were compared using high-resolution mass spectrometry. Paired analysis identified the MTEX-associated profile of 16 proteins that discriminated MTEX from NMETEX. We also identified the MTEX profile that discriminated between seven patients with no evidence of melanoma (NED) after therapy and eight with progressive disease (PD). Among 75 MTEX proteins overexpressed in PD patients, PDCD6IP (ALIX) had the highest discriminating value, while CNTN1 (contactin-1) was upregulated only in MTEX of NED patients. This is the first report documenting that proteomes of tumour-derived sEV in patients' plasma discriminate cancer from non-cancer and identify proteins with potential to serve as prognostic biomarkers in melanoma.


Assuntos
Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Melanoma/metabolismo , Plasma/metabolismo , Proteoma/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/sangue , Proteoglicanas de Sulfatos de Condroitina/imunologia , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Contactina 1/metabolismo , Progressão da Doença , Exossomos/química , Vesículas Extracelulares/química , Feminino , Humanos , Masculino , Espectrometria de Massas , Melanoma/química , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Plasma/química , Proteínas/metabolismo
19.
Nanomedicine (Lond) ; 16(8): 641-656, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33769068

RESUMO

Background: Thymoquinone (TQ) has potential anti-inflammatory, immunomodulatory and anticancer effects but its clinical use is limited by its low solubility, poor bioavailability and rapid clearance. Aim: To enhance systemic bioavailability and tumor-specific toxicity of TQ. Materials & methods: Cationic liposomal formulation of TQ (D1T) was prepared via ethanol injection method and their physicochemical properties, anticancer effects in orthotopic xenograft pancreatic tumor model and pharmacokinetic behavior of D1T relative to TQ were evaluated. Results: D1T showed prominent inhibition of pancreatic tumor progression, significantly greater in vivo absorption, approximately 1.5-fold higher plasma concentration, higher bioavailability, reduced volume of distribution and improved clearance relative to TQ. Conclusion: Encapsulation of TQ in cationic liposomal formulation enhanced its bioavailability and anticancer efficacy against xenograft pancreatic tumor.


Assuntos
Lipossomos , Benzoquinonas , Disponibilidade Biológica , Linhagem Celular Tumoral , Humanos , Solubilidade
20.
Mol Cancer Ther ; 20(12): 2585-2597, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34465594

RESUMO

Glioblastoma (GBM) is the most common primary brain cancer in adults where tumor cell heterogeneity and sex differences influence clinical outcomes. Here, we functionally characterize three male and three female patient-derived GBM cell lines, identify protumorigenic BTICs, and create novel male and female preclinical models of GBM. Cell lines were evaluated on the following features: proliferation, stemness, migration, tumorigenesis, clinical characteristics, and sensitivity to radiation, TMZ, rhTNFSF10 (rhTRAIL), and rhBMP4 All cell lines were classified as GBM according to epigenetic subtyping, were heterogenous and functionally distinct from one another, and re-capitulated features of the original patient tumor. In establishing male and female preclinical models, it was found that two male-derived GBM cell lines (QNS108 and QNS120) and one female-derived GBM cell line (QNS315) grew at a faster rate in female mice brains. One male-derived GBM cell line (QNS108) decreased survival in female mice in comparison with male mice. However, no survival differences were observed for mice injected with a female-derived cell line (QNS315). In summary, a panel of six GBM patient-derived cell lines were functionally characterized, and it was shown that BTIC lines can be used to construct sex-specific models with differential phenotypes for additional studies.


Assuntos
Células-Tronco Neoplásicas/metabolismo , Idoso , Animais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Caracteres Sexuais , Análise de Sobrevida
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