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1.
Int J Mol Sci ; 23(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36555109

RESUMO

Obstructive sleep apnea (OSA) is a highly prevalent condition, characterized by intermittent hypoxia (IH), sleep disruption, and altered autonomic nervous system function. OSA has been independently associated with dyslipidemia, insulin resistance, and metabolic syndrome. Brown adipose tissue (BAT) has been suggested as a modulator of systemic glucose tolerance through adaptive thermogenesis. Reductions in BAT mass have been associated with obesity and metabolic syndrome. No studies have systematically characterized the effects of chronic IH on BAT. Thus, we aimed to delineate IH effects on BAT and concomitant metabolic changes. C57BL/6J 8-week-old male mice were randomly assigned to IH during sleep (alternating 90 s cycles of 6.5% FIO2 followed by 21% FIO2) or normoxia (room air, RA) for 10 weeks. Mice were subjected to glucose tolerance testing and 18F-FDG PET-MRI towards the end of the exposures followed by BAT tissues analyses for morphological and global transcriptomic changes. Animals exposed to IH were glucose intolerant despite lower total body weight and adiposity. BAT tissues in IH-exposed mice demonstrated characteristic changes associated with "browning"-smaller lipids, increased vascularity, and a trend towards higher protein levels of UCP1. Conversely, mitochondrial DNA content and protein levels of respiratory chain complex III were reduced. Pro-inflammatory macrophages were more abundant in IH-exposed BAT. Transcriptomic analysis revealed increases in fatty acid oxidation and oxidative stress pathways in IH-exposed BAT, along with a reduction in pathways related to myogenesis, hypoxia, and IL-4 anti-inflammatory response. Functionally, IH-exposed BAT demonstrated reduced absorption of glucose on PET scans and reduced phosphorylation of AKT in response to insulin. Current studies provide initial evidence for the presence of a maladaptive response of interscapular BAT in response to chronic IH mimicking OSA, resulting in a paradoxical divergence, namely, BAT browning but tissue-specific and systemic insulin resistance. We postulate that oxidative stress, mitochondrial dysfunction, and inflammation may underlie these dichotomous outcomes in BAT.


Assuntos
Resistência à Insulina , Síndrome Metabólica , Apneia Obstrutiva do Sono , Masculino , Animais , Camundongos , Resistência à Insulina/fisiologia , Síndrome Metabólica/complicações , Camundongos Endogâmicos C57BL , Hipóxia/metabolismo , Obesidade/complicações , Insulina , Glucose/metabolismo , Apneia Obstrutiva do Sono/metabolismo , Tecido Adiposo Marrom/metabolismo , Sono
2.
Nanomedicine ; 36: 102414, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34171468

RESUMO

Drug penetration through the skin is significant for both transdermal and dermal delivery. One mechanism that has attracted attention over the last two decades is the transport pathway of nanoparticles via hair follicle, through the epidermis, directly to the pilosebaceous unit and blood vessels. Studies demonstrate that particle size is an important factor for drug penetration. However, in order to gain more information for the purpose of improving this mode of drug delivery, a thorough understanding of the optimal physical particle properties is needed. In this study, we fabricated fluorescently labeled gold nanoparticles (GNP) with a tight control over the size and shape. The effect of the particles' physical parameters on follicular penetration was evaluated histologically. We used horizontal human skin sections and found that the optimal size for polymeric particles is 0.25 µm. In addition, shape penetration experiments revealed gold nanostars' superiority over spherical particles. Our findings suggest the importance of the particles' physical properties in the design of nanocarriers delivered to the pilosebaceous unit.


Assuntos
Ouro , Folículo Piloso/metabolismo , Nanopartículas Metálicas , Ouro/química , Ouro/farmacocinética , Ouro/farmacologia , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico
3.
Adv Exp Med Biol ; 1225: 89-98, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030649

RESUMO

Cancer recurrence is one of the most imminent problems in the current world of medicine, and it is responsible for most of the cancer-related death rates worldwide. Long-term administration of anticancer cytotoxic drugs may act as a double-edged sword, as necrosis may lead to renewed cancer progression and treatment resistance. The lack of nutrients, coupled with the induced hypoxia, triggers cell death and secretion of signals that affect the tumor niche. Many efforts have been made to better understand the contribution of hypoxia and metabolic stress to cancer progression and resistance, but mostly with respect to inflammation. Here we provide an overview of the direct anticancer effects of necrotic signals, which are not necessarily mediated by inflammation and the role of DAMPs (damage-associated molecular patterns) on the formation of a pro-cancerous environment.


Assuntos
Recidiva Local de Neoplasia , Neoplasias/patologia , Microambiente Tumoral , Morte Celular , Humanos , Necrose
4.
Int J Mol Sci ; 21(20)2020 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-33081011

RESUMO

The currently accepted imaging methods have been a central hurdle to imaging the finer details of tumor behavior in three-dimensional (3D) ex vivo multicellular culture models. In our search for an improved way of imaging tumor behavior in its physiological-like niche, we developed a simple, efficient, and straightforward procedure using standard reagents and imaging equipment that significantly enhanced 3D imaging up to a ~200-micron depth. We tested its efficacy on pancreatic spheroids, prototypes of high-density tissues that are difficult to image. We found we could both save time with this method and extract information about pancreatic tumor spheroids that previously was difficult to obtain. We were able to discern clear differences in the organization of pancreatic tumor spheroids generated from different origins, suggesting cell-specific, inherent, bottom-up organization with a correlation to the level of malignancy. We also examined the dynamic changes in the spheroids at predetermined time points, providing important information related to tissue morphogenesis and its metabolic state. Lastly, this process enabled us to assess a drug vehicle's potential to penetrate dense tumor tissue by improving our view of the inert particles' diffusion in the 3D spheroid. This clearing method, a simple procedure, can open the door to more accurate imaging and reveal more about cancer behavior.


Assuntos
Imageamento Tridimensional , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Esferoides Celulares/patologia , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Microambiente Tumoral , Neoplasias Pancreáticas
5.
Int J Mol Sci ; 21(14)2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32708166

RESUMO

During the metastasis process, tumor cells invade the blood circulatory system directly from venous capillaries or indirectly via lymphatic vessels. Understanding the relative contribution of each pathway and identifying the molecular targets that affect both processes is critical for reducing cancer spread. Methionine aminopeptidase 2 (MetAp2) is an intracellular enzyme known to modulate angiogenesis. In this study, we investigated the additional role of MetAp2 in lymphangiogenesis. A histological staining of tumors from human breast-cancer donors was performed in order to detect the level and the localization of MetAp2 and lymphatic capillaries. The basal enzymatic level and activity in vascular and lymphatic endothelial cells were compared, followed by loss of function studies determining the role of MetAp2 in lymphangiogenesis in vitro and in vivo. The results from the histological analyses of the tumor tissues revealed a high MetAp2 expression, with detectable sites of co-localization with lymphatic capillaries. We showed slightly reduced levels of the MetAp2 enzyme and MetAp2 mRNA expression and activity in primary lymphatic cells when compared to the vascular endothelial cells. The genetic and biochemical manipulation of MetAp2 confirmed the dual activity of the enzyme in both vascular and lymphatic remodulation in cell function assays and in a zebrafish model. We found that cancer-related lymphangiogenesis is inhibited in murine models following MetAp2 inhibition treatment. Taken together, our study provides an indication that MetAp2 is a significant contributor to lymphangiogenesis and carries a dual role in both vascular and lymphatic capillary formation. Our data suggests that MetAp2 inhibitors can be effectively used as anti-metastatic broad-spectrum drugs.


Assuntos
Inibidores da Angiogênese/farmacologia , Proliferação de Células/genética , Células Endoteliais/metabolismo , Linfangiogênese/genética , Metástase Linfática/genética , Metionil Aminopeptidases/metabolismo , Neovascularização Patológica/metabolismo , Animais , Animais Geneticamente Modificados , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Endotélio Vascular/metabolismo , Humanos , Metástase Linfática/patologia , Vasos Linfáticos/efeitos dos fármacos , Vasos Linfáticos/metabolismo , Masculino , Metionil Aminopeptidases/antagonistas & inibidores , Metionil Aminopeptidases/genética , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/enzimologia , O-(Cloroacetilcarbamoil)fumagilol/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
6.
Proc Natl Acad Sci U S A ; 113(48): E7828-E7836, 2016 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-27849577

RESUMO

Several factors are known to enhance adult hippocampal neurogenesis but a factor capable of inducing a long-lasting neurogenic enhancement that attenuates age-related neurogenic decay has not been described. Here, we studied hippocampal neurogenesis following conditional VEGF induction in the adult brain and showed that a short episode of VEGF exposure withdrawn shortly after the generation of durable new vessels (but not under conditions where newly made vessels failed to persist) is sufficient for neurogenesis to proceed at a markedly elevated level for many months later. Continual neurogenic increase over several months was not accompanied by accelerated exhaustion of the neuronal stem cell (NSC) reserve, thereby allowing neurogenesis to proceed at a markedly elevated rate also in old mice. Neurogenic enhancement by VEGF preconditioning was, in part, attributed to rescue of age-related NSC quiescence. Remarkably, VEGF caused extensive NSC remodelling manifested in transition of the enigmatic NSC terminal arbor onto long cytoplasmic processes engaging with and spreading over even remote blood vessels, a configuration reminiscent of early postnatal "juvenile" NSCs. Together, these findings suggest that VEGF preconditioning might be harnessed for long-term neurogenic enhancement despite continued exposure to an "aged" systemic milieu.


Assuntos
Envelhecimento , Giro Denteado/citologia , Células-Tronco Neurais/fisiologia , Neurogênese , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Forma Celular , Circulação Cerebrovascular , Giro Denteado/irrigação sanguínea , Giro Denteado/fisiologia , Feminino , Expressão Gênica , Masculino , Camundongos Transgênicos , Nicho de Células-Tronco
7.
Exp Eye Res ; 148: 74-78, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27260483

RESUMO

In today's modern pharmacologic approach to treating sight-threatening retinal vascular disorders, there is an increasing demand for a compact, mobile, lightweight and cost-effective fluorescein fundus camera to document the effects of antiangiogenic drugs on laser-induced choroidal neovascularization (CNV) in mice and other experimental animals. We have adapted the use of the Kowa Genesis Df Camera to perform Fundus Fluorescein Angiography (FFA) in mice. The 1 kg, 28 cm high camera has built-in barrier and exciter filters to allow digital FFA recording to a Compact Flash memory card. Furthermore, this handheld unit has a steady Indirect Lens Holder that firmly attaches to the main unit, that securely holds a 90 diopter lens in position, in order to facilitate appropriate focus and stability, for photographing the delicate central murine fundus. This easily portable fundus fluorescein camera can effectively record exceptional central retinal vascular detail in murine laser-induced CNV, while readily allowing the investigator to adjust the camera's position according to the variable head and eye movements that can randomly occur while the mouse is optimally anesthetized. This movable image recording device, with efficiencies of space, time, cost, energy and personnel, has enabled us to accurately document the alterations in the central choroidal and retinal vasculature following induction of CNV, implemented by argon-green laser photocoagulation and disruption of Bruch's Membrane, in the experimental murine model of exudative macular degeneration.


Assuntos
Corioide/irrigação sanguínea , Neovascularização de Coroide/diagnóstico por imagem , Angiofluoresceinografia/instrumentação , Fotografação/métodos , Inibidores da Angiogênese/uso terapêutico , Animais , Neovascularização de Coroide/tratamento farmacológico , Modelos Animais de Doenças , Angiofluoresceinografia/métodos , Processamento de Imagem Assistida por Computador/métodos , Camundongos
8.
Proc Natl Acad Sci U S A ; 110(33): 13528-33, 2013 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-23898174

RESUMO

Epoxyeicosatrienoic acids (EETs), lipid mediators produced by cytochrome P450 epoxygenases, regulate inflammation, angiogenesis, and vascular tone. Despite pleiotropic effects on cells, the role of these epoxyeicosanoids in normal organ and tissue regeneration remains unknown. EETs are produced predominantly in the endothelium. Normal organ and tissue regeneration require an active paracrine role of the microvascular endothelium, which in turn depends on angiogenic growth factors. Thus, we hypothesize that endothelial cells stimulate organ and tissue regeneration via production of bioactive EETs. To determine whether endothelial-derived EETs affect physiologic tissue growth in vivo, we used genetic and pharmacological tools to manipulate endogenous EET levels. We show that endothelial-derived EETs play a critical role in accelerating tissue growth in vivo, including liver regeneration, kidney compensatory growth, lung compensatory growth, wound healing, corneal neovascularization, and retinal vascularization. Administration of synthetic EETs recapitulated these results, whereas lowering EET levels, either genetically or pharmacologically, delayed tissue regeneration, demonstrating that pharmacological modulation of EETs can affect normal organ and tissue growth. We also show that soluble epoxide hydrolase inhibitors, which elevate endogenous EET levels, promote liver and lung regeneration. Thus, our observations indicate a central role for EETs in organ and tissue regeneration and their contribution to tissue homeostasis.


Assuntos
Eicosanoides/farmacologia , Células Endoteliais/metabolismo , Compostos de Epóxi/farmacologia , Neovascularização Fisiológica/fisiologia , Regeneração/fisiologia , Animais , Cromatografia Líquida , Eicosanoides/metabolismo , Epóxido Hidrolases/antagonistas & inibidores , Compostos de Epóxi/metabolismo , Olho/irrigação sanguínea , Imuno-Histoquímica , Rim/fisiologia , Fígado/fisiologia , Pulmão/fisiologia , Camundongos , Camundongos Transgênicos , Neovascularização Fisiológica/efeitos dos fármacos , Receptor TIE-2/genética , Regeneração/efeitos dos fármacos , Espectrometria de Massas em Tandem
9.
Nanomedicine ; 11(8): 1993-2002, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26247432

RESUMO

Oral delivery of poorly soluble and permeable drugs represents a significant challenge in drug development. The oral delivery of drugs remains to be the ultimate route of any drugs. However, in many cases, drugs are not absorbed well in the gastrointestinal tract, or they lose their activity. Polymer micelles were recognized as an effective carrier system for drug encapsulation, and are now studied as a vehicle for oral delivery of insoluble compounds. We characterized the properties of monomethoxy polyethylene glycol-poly lactic acid (mPEG-PLA) micelles, and visualized their internalization in mouse small intestine. Using Caco-2 cells as a cellular model, we studied the kinetics of particle uptake, their transport, and the molecular mechanism of their intestinal absorption. Moreover, by inhibiting specific endocytosis pathways, pharmacologically and genetically, we found that mPEG-PLA nanoparticle endocytosis is mediated by clathrin in an energy-dependent manner, and that the low-density lipoprotein receptor is involved. FROM THE CLINICAL EDITOR: Many current drugs used are non-water soluble and indeed, the ability to deliver these drugs via the gastrointestinal tract remains the holy grail for many researchers. The authors in this paper developed monomethoxy polyethylene glycol-poly lactic acid (mPEG-PLA) micelles as a drug nanocarrier, and studied the mechanism of uptake across intestinal cells. The findings should improve our current understanding and point to the development of more nanocarriers.


Assuntos
Portadores de Fármacos/farmacocinética , Intestino Delgado/metabolismo , Ácido Láctico/farmacocinética , Micelas , Polietilenoglicóis/farmacocinética , Polímeros/farmacocinética , Administração Oral , Animais , Células CACO-2 , Portadores de Fármacos/química , Endocitose , Humanos , Absorção Intestinal , Ácido Láctico/química , Camundongos Endogâmicos C57BL , Poliésteres , Polietilenoglicóis/química , Polímeros/química
10.
J Pharmacol Exp Ther ; 350(3): 506-19, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24939421

RESUMO

Obtustatin and viperistatin, members of the disintegrin protein family, served as lead compounds for the synthesis of linear and cyclic peptides containing the KTS binding motif. The most active linear peptide, a viperistatin analog, indicated the importance of Cys(19) and Cys(29), as well as the presence of Arg at position 24 for their biologic activity, and was used as the basic sequence for the synthesis of cyclic peptides. Vimocin (compound 6) and vidapin (compound 10) showed a high potency (IC50 = 0.17 nM) and intermediate efficacy (20 and 40%) in inhibition of adhesion of α1/α2 integrin overexpressor cells to respective collagens. Vimocin was more active in inhibition of the wound healing (53%) and corneal micropocket (17%) vascularization, whereas vidapin was more potent in inhibition of migration in the Matrigel tube formation assay (90%). Both compounds similarly inhibited proliferation (50-90%) of endothelial cells, and angiogenesis induced by vascular endothelial growth factor (80%) and glioma (55%) in the chorioallantoic membrane assay. These peptides were not toxic to endothelial cell cultures and caused no acute toxicity upon intravenous injection in mice, and were stable for 10-30 hours in human serum. The in vitro and in vivo potency of the peptides are consistent with conformational ensembles and "bioactive" space shared by obtustatin and viperistatin. These findings suggest that vimocin and vidapin can serve as dual α1ß1/α2ß1 integrin antagonists in antiangiogenesis and cancer therapy.


Assuntos
Inibidores da Angiogênese/farmacologia , Integrina alfa1beta1/antagonistas & inibidores , Integrina alfa2beta1/antagonistas & inibidores , Peptídeos Cíclicos/farmacologia , Venenos de Víboras/farmacologia , Inibidores da Angiogênese/química , Animais , Bovinos , Células Endoteliais da Veia Umbilical Humana , Humanos , Integrina alfa1beta1/metabolismo , Integrina alfa2beta1/metabolismo , Masculino , Camundongos , Peptídeos Cíclicos/química , Codorniz , Ratos , Venenos de Víboras/química
11.
Biomech Model Mechanobiol ; 23(1): 145-155, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37770729

RESUMO

Multi-cellular biomimetic models often comprise heterogenic geometries. Therefore, quantification of their mechanical properties-which is crucial for various biomedical applications-is a challenge. Due to its simplicity, linear fitting is traditionally used in analyzing force-displacement data of parallel compression measurements of multi-cellular clusters, such as tumor spheroids. However, the linear assumption would be artificial when the contact geometry is not planar. We propose here the integrated elasticity (IE) regression, which is based on extrapolation of established elastic theories for well-defined geometries, and is free, extremely simple to apply, and optimal for analyzing coarsely concave multi-cellular clusters. We studied here the quality of the data analysis in force measurements of tumor spheroids comprising different types of melanoma cells, using either the IE or the traditional linear regressions. The IE regression maintained excellent precision also when the contact geometry deviated from planarity (as shown by our image analysis). While the quality of the linear fittings was relatively satisfying, these predicted smaller elastic moduli as compared to the IE regression. This was in accordance with previous studies, in which the elastic moduli predicted by linear fits were smaller compared to those obtained by well-established methods. This suggests that linear regressions underestimate the elastic constants of bio-samples even in cases where the fitting precision seems satisfying, and highlights the need in alternative methods as the IE scheme. For comparison between different types of spheroids we further recommend to increase the soundness by regarding relative moduli, using universal reference samples.


Assuntos
Fenômenos Mecânicos , Neoplasias , Humanos , Elasticidade , Módulo de Elasticidade
12.
Sci Adv ; 10(22): eadj4370, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38809990

RESUMO

Tumor heterogeneity is a primary factor that contributes to treatment failure. Predictive tools, capable of classifying cancer cells based on their functions, may substantially enhance therapy and extend patient life span. The connection between cell biomechanics and cancer cell functions is used here to classify cells through mechanical measurements, via particle uptake. Machine learning (ML) was used to classify cells based on single-cell patterns of uptake of particles with diverse sizes. Three pairs of human cancer cell subpopulations, varied in their level of drug resistance or malignancy, were studied. Cells were allowed to interact with fluorescently labeled polystyrene particles ranging in size from 0.04 to 3.36 µm and analyzed for their uptake patterns using flow cytometry. ML algorithms accurately classified cancer cell subtypes with accuracy rates exceeding 95%. The uptake data were especially advantageous for morphologically similar cell subpopulations. Moreover, the uptake data were found to serve as a form of "normalization" that could reduce variation in repeated experiments.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Aprendizado de Máquina , Neoplasias , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Tamanho da Partícula , Algoritmos , Poliestirenos/química , Citometria de Fluxo
13.
Adv Mater ; 36(13): e2311109, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38127403

RESUMO

Glioblastoma multiforme (GBM) is notoriously resistant to immunotherapy due to its intricate immunosuppressive tumor microenvironment (TME). Dysregulated cholesterol metabolism is implicated in the TME and promotes tumor progression. Here, it is found that cholesterol levels in GBM tissues are abnormally high, and glioma-supportive macrophages (GSMs), an essential "cholesterol factory", demonstrate aberrantly hyperactive cholesterol metabolism and efflux, providing cholesterol to fuel GBM growth and induce CD8+ T cells exhaustion. Bioinformatics analysis confirms that high 7-dehydrocholesterol reductase (DHCR7) level in GBM tissues associates with increased cholesterol biosynthesis, suppressed tumoricidal immune response, and poor patient survival, and DHCR7 expression level is significantly elevated in GSMs. Therefore, an intracavitary sprayable nanoregulator (NR)-encased hydrogel system to modulate cholesterol metabolism of GSMs is reported. The degradable NR-mediated ablation of DHCR7 in GSMs effectively suppresses cholesterol supply and activates T-cell immunity. Moreover, the combination of Toll-like receptor 7/8 (TLR7/8) agonists significantly promotes GSM polarization to antitumor phenotypes and ameliorates the TME. Treatment with the hybrid system exhibits superior antitumor effects in the orthotopic GBM model and postsurgical recurrence model. Altogether, the findings unravel the role of GSMs DHCR7/cholesterol signaling in the regulation of TME, presenting a potential treatment strategy that warrants further clinical trials.


Assuntos
Neoplasias Encefálicas , Dissacarídeos , Glioblastoma , Glioma , Glucuronatos , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Linfócitos T CD8-Positivos/metabolismo , Hidrogéis/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Glioma/patologia , Macrófagos/metabolismo , Imunoterapia , Colesterol , Microambiente Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo
14.
Angiogenesis ; 16(2): 405-16, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23150059

RESUMO

Prominin-1, a pentaspan transmembrane protein, is a unique cell surface marker commonly used to identify stem cells, including endothelial progenitor cells and cancer stem cells. However, recent studies have shown that prominin-1 expression is not restricted to stem cells but also occurs in modified forms in many mature adult human cells. Although prominin-1 has been studied extensively as a stem cell marker, its physiological function of the protein has not been elucidated. We investigated prominin-1 function in two cell lines, primary human endothelial cells and B16-F10 melanoma cells, both of which express high levels of prominin-1. We found that prominin-1 directly interacts with the angiogenic and tumor survival factor vascular endothelial growth factor (VEGF) in both the primary endothelial cells and the melanoma cells. Knocking down prominin-1 in the endothelial cells disrupted capillary formation in vitro and decreased angiogenesis in vivo. Similarly, tumors derived from prominin-1 knockdown melanoma cells had a reduced growth rate in vivo. Further, melanoma cells with knocked down prominin-1 had diminished ability to interact with VEGF, which was associated with decreased bcl-2 protein levels and increased apoptosis. In vitro studies with soluble prominin-1 showed that it stabilized dimer formation of VEGF164, but not VEGF121. Taken together, our findings support the notion that prominin-1 plays an active role in cell growth through its ability to interact and potentiate the anti-apoptotic and pro-angiogenic activities of VEGF. Additionally, prominin-1 promotes tumor growth by supporting angiogenesis and inhibiting tumor cell apoptosis.


Assuntos
Antígenos CD/metabolismo , Glicoproteínas/metabolismo , Peptídeos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Antígeno AC133 , Apoptose , Western Blotting , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Humanos , Imuno-Histoquímica , Melanoma/patologia , Ligação Proteica , Reação em Cadeia da Polimerase em Tempo Real
15.
Discov Nano ; 18(1): 89, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37382727

RESUMO

Porous metals have gained interest in many fields such as biomedicine, electronics, and energy. Despite the many benefits that these structures may offer, one of the major challenges in utilizing porous metals is to incorporate active compounds, either small molecules or macromolecules, on these surfaces. Coatings that contain active molecules have previously been used for biomedical applications to enable the slow release of drugs, e.g., with drug-eluting cardiovascular stents. However, direct deposition of organic materials on metals by coatings is very difficult due to the challenge of obtaining uniform coatings, as well as issues related to layer adherence and mechanical stability. Our study describes an optimization of a production process of different porous metals, aluminum, gold, and titanium, using wet-etching. Pertinent physicochemical measurements were carried out to characterize the porous surfaces. Following the production of porous metal surface, a new methodology for incorporating active materials onto the metals by using mechanical entrapment of polymeric nanoparticles in metal pores was developed. To demonstrate our concept of active material incorporation, we produced an odor-releasing metal object with embedded particles loaded with thymol, an odoriferous molecule. Polymer particles were placed inside nanopores in a 3D-printed titanium ring. Chemical analysis, followed by smell tests, indicated that the smell intensity lasts significantly longer in the porous material containing the nanoparticles, compared with the free thymol.

16.
Drug Deliv Transl Res ; 13(5): 1170-1182, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35637333

RESUMO

Methionine aminopeptidase 2 (MetAp2) inhibition has been recognized as a promising approach for suppressing angiogenesis and cancer progression. Small molecule fumagillol derivatives with adamantane side groups were synthesized and evaluated for MetAp2 inhibition activity, and a lead molecule with superior abilities to inhibit the enzymatic activity of MetAp2 was identified. The compound, referred to as AD-3281, effectively suppressed proliferation of cancer and endothelial cells and impaired tube formation of endothelial cells in vitro. When administered systemically, AD-3281 was well tolerated and led to a significant suppression of human melanoma and mammary tumor xenografts grown in mice. The activity in vivo was associated with reduced angiogenesis and tumor proliferation as detected histologically. In order to develop a formulation that can solubilize AD-3281 with a minimal content of organic solvents, biodegradable nanoparticles comprised of poly-lactic-co-glycolic acid (PLGA) were fabricated and characterized. Compared with the free compound, AD-3281-loaded nanoparticles showed an advantageous cellular availability and uptake, leading to higher activity in cells and better transport in three-dimensional (3D) cultures. Taken together, we introduce a novel MetAp2 inhibitor with high anti-cancer activity and a stable nano-formulation with a high potential for future clinical translation.


Assuntos
Células Endoteliais , Neoplasias , Humanos , Animais , Camundongos , Aminopeptidases , Metaloendopeptidases
17.
APL Bioeng ; 7(1): 016113, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36960390

RESUMO

Cancer phenotypes are often associated with changes in the mechanical states of cells and their microenvironments. Numerous studies have established correlations between cancer cell malignancy and cell deformability at the single-cell level. The mechanical deformation of cells is required for the internalization of large colloidal particles. Compared to normal epithelial cells, cancer cells show higher capacities to distort their shapes during the engulfment of external particles, thus performing phagocytic-like processes more efficiently. This link between cell deformability and particle uptake suggests that the cell's adherence state may affect this particle uptake, as cells become stiffer when plated on a more rigid substrate and vice versa. Based on this, we hypothesized that cancer cells of the same origin, which are subjected to external mechanical cues through attachment to surfaces with varying rigidities, may express different capacities to uptake foreign particles. The effects of substrate rigidity on cancer cell uptake of inert particles (0.8 and 2.4 µm) were examined using surfaces with physiologically relevant rigidities (from 0.5 to 64 kPa). Our data demonstrate a wave-like ("meandering") dependence of cell uptake on the rigidity of the culture substrate explained by a superposition of opposing physical and biological effects. The uptake patterns were inversely correlated with the expression of phosphorylated paxillin, indicating that the initial passive particle absorbance is the primary limiting step toward complete uptake. Overall, our findings may provide a foundation for mechanical rationalization of particle uptake design.

18.
Adv Healthc Mater ; 12(30): e2301548, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37315950

RESUMO

Blockage of blood supply while administering chemotherapy to tumors, using trans-arterial chemoembolization (TACE), is the most common treatment for intermediate and advanced-stage unresectable Hepatocellular carcinoma (HCC). However, HCC is characterized by a poor prognosis and high recurrence rates (≈30%), partly due to a hypoxic pro-angiogenic and pro-cancerous microenvironment. This study investigates how modifying tissue stress while improving drug exposure in target organs may maximize the therapeutic outcomes. Porous degradable polymeric microspheres (MS) are designed to obtain a gradual occlusion of the hepatic artery that nourishes the liver, while enabling efficient drug perfusion to the tumor site. The fabricated porous MS are introduced intrahepatically and designed to release a combination therapy of Doxorubicin (DOX) and Tirapazamine (TPZ), which is a hypoxia-activated prodrug. Liver cancer cell lines that are treated with the combination therapy under hypoxia reveal a synergic anti-proliferation effect. An orthotopic liver cancer model, based on N1-S1 hepatoma in rats, is used for the efficacy, biodistribution, and safety studies. Porous DOX-TPZ MS are very effective in suppressing tumor growth in rats, and induction tissue necrosis is associated with high intratumor drug concentrations. Porous particles without drugs show some advantages over nonporous particles, suggesting that morphology may affect the treatment outcomes.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Ratos , Animais , Neoplasias Hepáticas/tratamento farmacológico , Carcinoma Hepatocelular/tratamento farmacológico , Microesferas , Distribuição Tecidual , Porosidade , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Tirapazamina/farmacologia , Tirapazamina/uso terapêutico , Hipóxia/tratamento farmacológico , Microambiente Tumoral
19.
ACS Nano ; 17(3): 1946-1958, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36468629

RESUMO

With the aim to locally enhance the efficacy of cancer nanotherapies, here we present metal iron based magnetoplasmonic drug-loaded nanocapsules (MAPSULES), merging powerful external magnetic concentration in the tumor and efficient photothermal actuation to locally boost the drug therapeutic action at ultralow drug concentrations. The MAPSULES are composed of paclitaxel-loaded polylactic-co-glycolic acid (PLGA) nanoparticles partially coated by a nanodome shape iron/silica semishell. The iron semishell has been designed to present a ferromagnetic vortex for incorporating a large quantity of ferromagnetic material while maintaining high colloidal stability. The large iron semishell provides very strong magnetic manipulation via magnetophoretic forces, enabling over 10-fold higher trapping efficiency in microfluidic channels than typical superparamagnetic iron oxide nanoparticles. Moreover, the iron semishell exhibits highly damped plasmonic behavior, yielding intense broadband absorbance in the near-infrared biological windows and photothermal efficiency similar to the best plasmonic nanoheaters. The in vivo therapeutic assays in a mouse xenograft tumor model show a high amplification of the therapeutic effects by combining magnetic concentration and photothermal actuation in the tumor, leading to a complete eradication of the tumors at ultralow nanoparticle and drug concentration (equivalent to only 1 mg/kg PLGA nanoparticles containing 8 µg/kg of paclitaxel, i.e., 100-500-fold lower than the therapeutic window of the free and PLGA encapsulated drug and 13-3000-fold lower than current nanotherapies combining paclitaxel and light actuation). These results highlight the strength of this externally controlled and amplified therapeutic approach, which could be applied to locally boost a wide variety of drugs for different diseases.


Assuntos
Nanocápsulas , Nanopartículas , Humanos , Animais , Camundongos , Ferro , Linhagem Celular Tumoral , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico
20.
Cancers (Basel) ; 15(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36672446

RESUMO

Cannabis sativa plants have a wide diversity in their metabolite composition among their different chemovars, facilitating diverse anti-tumoral effects on cancer cells. This research examined the anti-tumoral effects of 24 cannabis extracts representative of three primary types of chemovars on head and neck squamous cell carcinoma (HNSCC). The chemical composition of the extracts was determined using High-Performance Liquid Chromatography (HPLC) and Mass Spectrometry (MS). The most potent anti-tumoral extracts were type III decarboxylated extracts, with high levels of Cannabidiol (CBD). We identified extract 296 (CAN296) as the most potent in inducing HNSCC cell death via proapoptotic and anti-proliferative effects. Using chemical fractionation of CAN296, we identified the CBD fraction as the primary inducer of the anti-tumoral activity. We succeeded in defining the combination of CBD with cannabichromene (CBC) or tetrahydrocannabinol (THC) present in minute concentrations in the extract, yielding a synergic impact that mimics the extract's full effect. The cytotoxic effect could be maximized by combining CBD with either CBC or THC in a ratio of 2:1. This research suggests using decarboxylated CBD-type extracts enriched with CBC for future preclinical trials aimed at HNSCC treatment.

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