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1.
Carbohydr Polym ; 330: 121839, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368115

RESUMO

Cancer, a global health challenge of utmost severity, necessitates innovative approaches beyond conventional treatments (e.g., surgery, chemotherapy, and radiation therapy). Unfortunately, these approaches frequently fail to achieve comprehensive cancer control, characterized by inefficacy, non-specific drug distribution, and the emergence of adverse side effects. Nanoscale systems based on natural polymers like chitosan have garnered significant attention as promising platforms for cancer diagnosis and therapy owing to chitosan's inherent biocompatibility, biodegradability, nontoxicity, and ease of functionalization. Herein, recent advancements pertaining to the applications of chitosan nanoparticles in cancer imaging and drug/gene delivery are deliberated. The readers are introduced to conventional non-stimuli-responsive and stimuli-responsive chitosan-based nanoplatforms. External triggers like light, heat, and ultrasound and internal stimuli such as pH and redox gradients are highlighted. The utilization of chitosan nanomaterials as contrast agents or scaffolds for multimodal imaging techniques e.g., magnetic resonance, fluorescence, and nuclear imaging is represented. Key applications in targeted chemotherapy, combination therapy, photothermal therapy, and nucleic acid delivery using chitosan nanoformulations are explored for cancer treatment. The immunomodulatory effects of chitosan and its role in impacting the tumor microenvironment are analyzed. Finally, challenges, prospects, and future outlooks regarding the use of chitosan-based nanosystems are discussed.


Assuntos
Quitosana , Nanopartículas , Nanoestruturas , Neoplasias , Humanos , Quitosana/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Nanoestruturas/química , Nanopartículas/uso terapêutico , Nanopartículas/química , Microambiente Tumoral
2.
Methods Mol Biol ; 2748: 109-118, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38070111

RESUMO

The development of advanced biological models like microphysiological systems, able to rebuild the complexity of the physiological and/or pathological environments at a single-cell detail level in an in-vivo-like approach, is proving to be a promising tool to understand the mechanisms of interactions between different cell populations and main features of several diseases. In this frame, the tumor-immune microenvironment on a chip represents a powerful tool to profile key aspects of cancer progression, immune activation, and response to therapy in several immuno-oncology applications. In the present chapter, we provide a protocol to identify and characterize the time evolution of apoptosis by time-lapse fluorescence and confocal imaging in a 3D microfluidic coculture murine model including cancer and spleen cells.


Assuntos
Neoplasias , Animais , Humanos , Camundongos , Caspase 3 , Neoplasias/patologia , Microfluídica/métodos , Apoptose , Dispositivos Lab-On-A-Chip , Microambiente Tumoral
3.
Carbohydr Polym ; 304: 120510, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36641174

RESUMO

Breast cancer is known as the most common invasive malignancy in women with the highest mortality rate worldwide. This concerning disease may be presented in situ (relatively easier treatment) or be invasive, especially invasive ductal carcinoma which is highly worrisome nowadays. Among several strategies used in breast cancer treatment, nanotechnology-based targeted therapy is currently being investigated, as it depicts advanced technological features able of preventing drugs' side effects on normal cells while effectively acting on tumor cells. In this context, carbohydrate polymer-based nanocomposites have gained particular interest among the biomedical community for breast cancer therapy applications due to their advantage features, including abundance in nature, biocompatibility, straightforward fabrication methods, and good physicochemical properties. In this review, the physicochemical properties and biological activities of carbohydrate polymers and their derivate nanocomposites were discussed. Then, various methods for the fabrication of carbohydrate polymer-based nanocomposites as well as their application in breast cancer therapy and future perspectives were discussed.


Assuntos
Neoplasias da Mama , Nanocompostos , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Polímeros/uso terapêutico , Polímeros/química , Nanocompostos/uso terapêutico , Nanocompostos/química , Carboidratos
4.
J Vis Exp ; (170)2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33999026

RESUMO

Complex disease models demand cutting-edge tools able to deliver physiologically and pathologically relevant, actionable insights, and unveil otherwise invisible processes. Advanced cell assays closely mimicking in vivo scenery are establishing themselves as novel ways to visualize and measure the bidirectional tumor-host interplay influencing the progression of cancer. Here we describe two versatile protocols to recreate highly controllable 2D and 3D co-cultures in microdevices, mimicking the complexity of the tumor microenvironment (TME), under natural and therapy-induced immunosurveillance. In section 1, an experimental setting is provided to monitor crosstalk between adherent tumor cells and floating immune populations, by bright field time-lapse microscopy. As an applicative scenario, we analyze the effects of anti-cancer treatments, such as the so-called immunogenic cancer cell death inducers on the recruitment and activation of immune cells. In section 2, 3D tumor-immune microenvironments are assembled in a competitive layout. Differential immune infiltration is monitored by fluorescence snapshots up to 72 h, to evaluate combination therapeutic strategies. In both settings, image processing steps are illustrated to extract a plethora of immune cell parameters (e.g., immune cell migration and interaction, response to therapeutic agents). These simple and powerful methods can be further tailored to simulate the complexity of the TME encompassing the heterogeneity and plasticity of cancer, stromal and immune cells subtypes, as well as their reciprocal interactions as drivers of cancer evolution. The compliance of these rapidly evolving technologies with live-cell high-content imaging can lead to the generation of large informative datasets, bringing forth new challenges. Indeed, the triangle ''co-cultures/microscopy/advanced data analysis" sets the path towards a precise problem parametrization that may assist tailor-made therapeutic protocols. We expect that future integration of cancer-immune on-a-chip with artificial intelligence for high-throughput processing will synergize a large step forward in leveraging the capabilities as predictive and preclinical tools for precision and personalized oncology.


Assuntos
Técnicas de Cocultura , Técnicas Analíticas Microfluídicas , Microambiente Tumoral/imunologia , Linhagem Celular Tumoral , Humanos , Leucócitos Mononucleares/imunologia
5.
Lab Chip ; 20(16): 3011-3023, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32700707

RESUMO

Prior work supports the hypothesis that ATP release through connexin hemichannels drives spontaneous Ca2+ signaling in non-sensory cells of the greater epithelial ridge (GER) in the developing cochlea; however, direct proof is lacking. To address this issue, we plated cochlear organotypic cultures (COCs) and whole cell-based biosensors with nM ATP sensitivity (ATP-WCBs) at the bottom and top of an ad hoc designed transparent microfluidic chamber, respectively. By performing dual multiphoton Ca2+ imaging, we monitored the propagation of intercellular Ca2+ waves in the GER of COCs and ATP-dependent Ca2+ responses in overlying ATP-WCBs. Ca2+ signals in both COCs and ATP-WCBs were inhibited by supplementing the extracellular medium with ATP diphosphohydrolase (apyrase). Spontaneous Ca2+ signals were strongly depressed in the presence of Gjb6-/- COCs, in which connexin 30 (Cx30) is absent and connexin 26 (Cx26) is strongly downregulated. In contrast, spontaneous Ca2+ signals were not affected by replacement of Panx1-/- with Panx1+/+ COCs in the microfluidic chamber. Similar results were obtained by estimating ATP release from COCs using a classical luciferin-luciferase bioluminescence assay. Therefore, connexin hemichannels and not pannexin 1 channels mediate the release of ATP that is responsible for Ca2+ wave propagation in the developing mouse cochlea. The technological advances presented here have the potential to shed light on a plethora of unrelated open issues that involve paracrine signaling in physiology and pathology and cannot be addressed with standard methods.


Assuntos
Trifosfato de Adenosina , Conexinas , Animais , Cóclea , Conexinas/genética , Junções Comunicantes , Camundongos , Proteínas do Tecido Nervoso , Transdução de Sinais
6.
Cell Rep ; 25(13): 3884-3893.e3, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30590056

RESUMO

A major challenge in cancer research is the complexity of the tumor microenvironment, which includes the host immunological setting. Inspired by the emerging technology of organ-on-chip, we achieved 3D co-cultures in microfluidic devices (integrating four cell populations: cancer, immune, endothelial, and fibroblasts) to reconstitute ex vivo a human tumor ecosystem (HER2+ breast cancer). We visualized and quantified the complex dynamics of this tumor-on-chip, in the absence or in the presence of the drug trastuzumab (Herceptin), a targeted antibody therapy directed against the HER2 receptor. We uncovered the capacity of the drug trastuzumab to specifically promote long cancer-immune interactions (>50 min), recapitulating an anti-tumoral ADCC (antibody-dependent cell-mediated cytotoxicity) immune response. Cancer-associated fibroblasts (CAFs) antagonized the effects of trastuzumab. These observations constitute a proof of concept that tumors-on-chip are powerful platforms to study ex vivo immunocompetent tumor microenvironments, to characterize ecosystem-level drug responses, and to dissect the roles of stromal components.


Assuntos
Antineoplásicos/farmacologia , Fibroblastos Associados a Câncer/patologia , Imunocompetência/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Animais , Fibroblastos Associados a Câncer/efeitos dos fármacos , Bovinos , Comunicação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Invasividade Neoplásica , Receptor ErbB-2/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Trastuzumab/farmacologia
7.
Sci Rep ; 7(1): 12737, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28986543

RESUMO

In this paper we discuss the applicability of numerical descriptors and statistical physics concepts to characterize complex biological systems observed at microscopic level through organ on chip approach. To this end, we employ data collected on a microfluidic platform in which leukocytes can move through suitably built channels toward their target. Leukocyte behavior is recorded by standard time lapse imaging. In particular, we analyze three groups of human peripheral blood mononuclear cells (PBMC): heterozygous mutants (in which only one copy of the FPR1 gene is normal), homozygous mutants (in which both alleles encoding FPR1 are loss-of-function variants) and cells from 'wild type' donors (with normal expression of FPR1). We characterize the migration of these cells providing a quantitative confirmation of the essential role of FPR1 in cancer chemotherapy response. Indeed wild type PBMC perform biased random walks toward chemotherapy-treated cancer cells establishing persistent interactions with them. Conversely, heterozygous mutants present a weaker bias in their motion and homozygous mutants perform rather uncorrelated random walks, both failing to engage with their targets. We next focus on wild type cells and study the interactions of leukocytes with cancerous cells developing a novel heuristic procedure, inspired by Lyapunov stability in dynamical systems.


Assuntos
Comunicação Celular , Leucócitos/patologia , Neoplasias/patologia , Linhagem Celular Tumoral , Movimento Celular , Humanos , Dispositivos Lab-On-A-Chip , Movimento (Física)
8.
Sci Rep ; 7(1): 1093, 2017 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-28439087

RESUMO

Immunotherapy efficacy relies on the crosstalk within the tumor microenvironment between cancer and dendritic cells (DCs) resulting in the induction of a potent and effective antitumor response. DCs have the specific role of recognizing cancer cells, taking up tumor antigens (Ags) and then migrating to lymph nodes for Ag (cross)-presentation to naïve T cells. Interferon-α-conditioned DCs (IFN-DCs) exhibit marked phagocytic activity and the special ability of inducing Ag-specific T-cell response. Here, we have developed a novel microfluidic platform recreating tightly interconnected cancer and immune systems with specific 3D environmental properties, for tracking human DC behaviour toward tumor cells. By combining our microfluidic platform with advanced microscopy and a revised cell tracking analysis algorithm, it was possible to evaluate the guided efficient motion of IFN-DCs toward drug-treated cancer cells and the succeeding phagocytosis events. Overall, this platform allowed the dissection of IFN-DC-cancer cell interactions within 3D tumor spaces, with the discovery of major underlying factors such as CXCR4 involvement and underscored its potential as an innovative tool to assess the efficacy of immunotherapeutic approaches.


Assuntos
Rastreamento de Células/métodos , Neoplasias do Colo/terapia , Células Dendríticas/imunologia , Imunoterapia/métodos , Microfluídica/métodos , Modelos Biológicos , Células Cultivadas , Humanos , Fatores Imunológicos/metabolismo , Interferon-alfa/metabolismo , Microscopia/métodos , Resultado do Tratamento
9.
Lab Chip ; 17(6): 1158-1166, 2017 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-28225104

RESUMO

Microfluidic impedance cytometry offers a simple non-invasive method for single-cell analysis. Coplanar electrode chips are especially attractive due to ease of fabrication, yielding miniaturized, reproducible, and ultimately low-cost devices. However, their accuracy is challenged by the dependence of the measured signal on particle trajectory within the interrogation volume, that manifests itself as an error in the estimated particle size, unless any kind of focusing system is used. In this paper, we present an original five-electrode coplanar chip enabling accurate particle sizing without the need for focusing. The chip layout is designed to provide a peculiar signal shape from which a new metric correlating with particle trajectory can be extracted. This metric is exploited to correct the estimated size of polystyrene beads of 5.2, 6 and 7 µm nominal diameter, reaching coefficient of variations lower than the manufacturers' quoted values. The potential impact of the proposed device in the field of life sciences is demonstrated with an application to Saccharomyces cerevisiae yeast.


Assuntos
Impedância Elétrica , Citometria de Fluxo/métodos , Técnicas Analíticas Microfluídicas/métodos , Eletrodos , Tamanho da Partícula , Poliestirenos , Leveduras/citologia
10.
Analyst ; 140(16): 5754-63, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26167770

RESUMO

Principal component analysis is applied to analyse the Raman maps collected on carbon nanotubes at different degrees of oxidation and functionalization with dye labeling molecules. The results are used to demonstrate that the technique is extremely effective in clustering data and comparing preparation protocols, so that it enables drawing of a fast and reliable classification of the molecule propensity to interact with pristine and oxidized carbon nanotubes. The spectral findings are supported and elucidated by several experimental techniques, thermogravimetry and steady-state and time-resolved fluorescence measurements, and by computational modeling, showing that the proposed methodology could represent a powerful and routine test for the rational design of functional nanostructures.


Assuntos
Corantes/química , Nanoestruturas/química , Nanotubos de Carbono/química , Análise Multivariada , Análise Espectral Raman
11.
Biomed Mater ; 10(3): 035005, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-26040849

RESUMO

In this work, titanium (Ti) supports have been coated with glass-ceramic films for possible applications as biomedical implant materials in regenerative medicine. For the film preparation, a pulsed laser deposition (PLD) technique has been applied. The RKKP glass-ceramic material, used for coating deposition, was a sol-gel derived target of the following composition: Ca-19.4, P-4.6, Si-17.2, O-43.5, Na-1.7, Mg-1.3, F-7.2, K-0.2, La-0.8, Ta-4.1 (all in wt%). The prepared coatings were compact and uniform, characterised by a nanometric average surface roughness. The biocompatibility and cell-friendly properties of the RKKP glass-ceramic material have been tested. Cell metabolic activity and proliferation of human colon carcinoma CaCo-2 cells seeded on RKKP films showed the same exponential trend found in the control plastic substrates. By the phalloidin fluorescence analysis, no significant modifications in the actin distribution were revealed in cells grown on RKKP films. Moreover, in these cells a high mRNA expression of markers involved in protein synthesis, proliferation and differentiation, such as villin (VIL1), alkaline phosphatase (ALP1), ß-actin (ß-ACT), Ki67 and RPL34, was recorded. In conclusion, the findings, for the first time, demonstrated that the RKKP glass-ceramic material allows the adhesion, growth and differentiation of the CaCo-2 cell line.


Assuntos
Cerâmica/química , Materiais Revestidos Biocompatíveis/química , Titânio/química , Actinas/metabolismo , Células CACO-2 , Adesão Celular , Diferenciação Celular , Proliferação de Células , Expressão Gênica , Humanos , Teste de Materiais , Próteses e Implantes , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Medicina Regenerativa , Engenharia Tecidual , Alicerces Teciduais/química
12.
Cell Cycle ; 7(24): 3869-77, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19098425

RESUMO

NG108-15 cells differentiate into neurons by 1 mM sodium butyrate (NaB) treatment. Differentiated cells resulted more resistant to staurosporine (STS) than proliferating cells. In particular, STS treatment decreased Bcl-2 and Bcl-x(L) content in mitochondria of proliferating cells, but not in mitochondria of differentiated cells. Bad was phosphorylated and downregulated only in differentiated cells. Bax accumulated in the mitochondria of proliferating but not differentiated cells. Mitochondrial release of cytochrome c was observed in proliferating cells, whereas mitochondria of differentiated cells retained cytochrome c. Proliferating cells treated with STS accumulated Endo G and AIF in the nucleus. By contrast, differentiated cells did not show such nuclear accumulation. Treatment of differentiated cells with Insulin-like Growth Factor-1 (IGF-1) and STS resulted in a 17.1% increase of cell viability. The survival role of IGF-1 was demonstrated by treating differentiated cells with an anti-IGF-1 neutralizing antibody. Such treatment significantly increased STS-induced cell death. Electrophysiology studies showed that in STS-treated cells membrane potential oscillations were reduced in amplitude and did not give rise to spontaneous action potentials (APs). However, the percentage of cells yielding overshooting APs returned to control values after STS removal. It is concluded that neuronal differentiation of NG108-15 cells induces resistance to apoptotic cell death and that IGF-1 plays a central role in sustaining this mechanism.


Assuntos
Apoptose , Fator de Crescimento Insulin-Like I/metabolismo , Neurônios/citologia , Estaurosporina/farmacologia , Animais , Fator de Indução de Apoptose/metabolismo , Diferenciação Celular , Linhagem Celular , Eletrofisiologia , Endodesoxirribonucleases/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Estaurosporina/antagonistas & inibidores , Proteína X Associada a bcl-2/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo , Proteína bcl-X/metabolismo
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