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1.
J Nanobiotechnology ; 19(1): 3, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407564

RESUMO

BACKGROUND: Despite the highly expected clinical application of nanoparticles (NPs), the translation of NPs from lab to the clinic has been relatively slow. Co-culture 3D spheroids account for the 3D arrangement of tumor cells and stromal components, e.g., cancer-associated fibroblasts (CAFs) and extracellular matrix, recapitulating microenvironment of head and neck squamous cell carcinoma (HNSCC). In the present study, we investigated how the stroma-rich tumor microenvironment affects the uptake, penetration, and photodynamic efficiency of three lipid-based nanoformulations of approved in EU photosensitizer temoporfin (mTHPC): Foslip® (mTHPC in conventional liposomes), drug-in-cyclodextrin-in-liposomes (mTHPC-DCL) and extracellular vesicles (mTHPC-EVs). RESULTS: Collagen expression in co-culture stroma-rich 3D HNSCC spheroids correlates with the amount of CAFs (MeWo cells) in individual spheroid. The assessment of mTHPC loading demonstrated that Foslip®, mTHPC-DCL and mTHPC-EVs encapsulated 0.05 × 10- 15 g, 0.07 × 10- 15 g, and 1.3 × 10- 15 g of mTHPC per nanovesicle, respectively. The mid-penetration depth of mTHPC NPs in spheroids was 47.8 µm (Foslip®), 87.8 µm (mTHPC-DCL), and 49.7 µm (mTHPC-EVs), irrespective of the percentage of stromal components. The cellular uptake of Foslip® and mTHPC-DCL was significantly higher in stroma-rich co-culture spheroids and was increasing upon the addition of serum in the culture medium. Importantly, we observed no significant difference between PDT effect in monoculture and co-culture spheroids treated with lipid-based NPs. Overall, in all types of spheroids mTHPC-EVs demonstrated outstanding total cellular uptake and PDT efficiency comparable to other NPs. CONCLUSIONS: The stromal microenvironment strongly affects the uptake of NPs, while the penetration and PDT efficacy are less sensitive to the presence of stromal components. mTHPC-EVs outperform other lipid nanovesicles due to the extremely high loading capacity. The results of the present study enlarge our understanding of how stroma components affect the delivery of NPs into the tumors.


Assuntos
Neoplasias de Cabeça e Pescoço/metabolismo , Metabolismo dos Lipídeos , Mesoporfirinas/metabolismo , Fotoquimioterapia/métodos , Carcinoma , Técnicas de Cocultura , Matriz Extracelular , Vesículas Extracelulares , Células HT29 , Humanos , Lipídeos , Lipossomos , Nanopartículas , Fármacos Fotossensibilizantes/uso terapêutico , Esferoides Celulares , Microambiente Tumoral
2.
Int J Mol Sci ; 22(4)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671198

RESUMO

Near-infrared (NIR) fluorescence-guided surgery is an innovative technique for the real-time visualization of resection margins. The aim of this study was to develop a head and neck multicellular tumor spheroid model and to explore the possibilities offered by it for the evaluation of cameras for NIR fluorescence-guided surgery protocols. FaDu spheroids were incubated with indocyanine green (ICG) and then included in a tissue-like phantom. To assess the capability of Fluobeam® NIR camera to detect ICG in tissues, FaDu spheroids exposed to ICG were embedded in 2, 5 or 8 mm of tissue-like phantom. The fluorescence signal was significantly higher between 2, 5 and 8 mm of depth for spheroids treated with more than 5 µg/mL ICG (p < 0.05). The fluorescence intensity positively correlated with the size of spheroids (p < 0.01), while the correlation with depth in the tissue-like phantom was strongly negative (p < 0.001). This multicellular spheroid model embedded in a tissue-like phantom seems to be a simple and reproducible in vitro tumor model, allowing a comparison of NIR cameras. The ideal configuration seems to be 450 µm FaDu spheroids incubated for 24 hours with 0.05 mg/ml of ICG, ensuring the best stability, toxicity, incorporation and signal intensity.


Assuntos
Cabeça/diagnóstico por imagem , Imageamento Tridimensional , Modelos Biológicos , Pescoço/diagnóstico por imagem , Neoplasias/cirurgia , Fotografação/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho , Esferoides Celulares/citologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Fluorescência , Humanos , Verde de Indocianina/toxicidade , Cinética , Imagens de Fantasmas
3.
Photochem Photobiol Sci ; 14(12): 2203-12, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26496965

RESUMO

There is currently great interest in the development of efficient and specific carrier delivery platforms for systemic photodynamic therapy. Therefore, we aimed to develop covalent conjugates between the photosensitizer chlorin e6 (Ce6) and PAMAM G4.5 dendrimers. Singlet oxygen generation (SOG) efficiency and fluorescence emission were moderately affected by the covalent binding of the Ce6 to the dendrimer. Compared to free Ce6, PAMAM anchored Ce6 displays a much higher photodynamic effect, which is ascribable to better internalization in a tumor cell model. Intracellular fate and internalization pathway of our different compounds were investigated using specific inhibition conditions and confocal fluorescence microscopy. Free Ce6 was shown to enter the cells by a simple diffusion mechanism, while G4.5-Ce6-PEG internalization was dependent on the caveolae pathway, whereas G4.5-Ce6 was subjected to the clathrin-mediated endocytosis pathway. Subcellular localization of PAMAM anchored Ce6, PEGylated or not, was very similar suggesting that the nanoparticles behave similarly in the cells. As a conclusion, we have demonstrated that PEGylated G4.5 PAMAM-Ce6 dendrimers may offer effective biocompatible nanoparticles for improved photodynamic treatment in a preclinical tumor model.


Assuntos
Dendrímeros/química , Dendrímeros/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Clorofilídeos , Dendrímeros/administração & dosagem , Dendrímeros/farmacocinética , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacocinética , Porfirinas/administração & dosagem , Porfirinas/farmacocinética , Oxigênio Singlete/metabolismo
4.
Lasers Med Sci ; 30(9): 2381-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25563461

RESUMO

The aim of this article is to give an insight into the future of photodynamic therapy (PDT) in head and neck squamous cell carcinoma (HNSCC). Through the combination of a photosensitizing agent with light and oxygen, PDT produces highly cytotoxic reactive oxygen species leading to selective tumor eradication. PDT is an attractive treatment for focal therapy of localized tumors, especially in the case of unresectable tumors. In HNSCC, over 1500 patients have been treated by PDT, and the majority of them responded quite favorably to this treatment. However, the non-negligible photosensitization of healthy tissue is a major limitation for the clinical application of PDT. Improvement in tumor selectivity is the main challenge that can be taken up by the use of a new generation of photosensitizing nanoparticles. Passive targeting, by using functionalised nanocarriers to target to overexpressed transmembrane receptors afford attractive solutions. To this day, epidermal growth factor receptor (EGFR) remains the only validated molecular target for HNSCC, and photosensitizer immunoconjugates to EGFR have been developed for the intracellular delivery of photosensitizing agents. Depending on coordinated research between biomarkers, specific ligands, and photosensitizers, similar approaches could be rapidly developed. In addition, some photosensitizers hold high fluorescence yield and therefore could emerge as theranostic agents.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Terapia de Alvo Molecular/métodos , Fotoquimioterapia/métodos , Animais , Humanos , Pesquisa Translacional Biomédica
5.
J Urol ; 190(2): 731-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23353049

RESUMO

PURPOSE: We studied how to avoid irritative bladder symptoms after bladder photodynamic therapy, such as urgency, frequency and pain, which are associated with the inflammation and destruction of normal urothelium. MATERIALS AND METHODS: Rats bearing orthotopic bladder tumors were instilled with hexyl-aminolevulinate and illuminated with red light at a high vs low (100 vs 15 mW/cm(2)) fluence rate. Cystectomy specimens 48 hours after treatment were subjected to anatomopathological examination. Inflammatory reaction and apoptosis were evaluated. In vivo photobleaching was assessed during illumination at each fluence rate. RESULTS: All superficial tumors were eradicated irrespective of light dose and fluence rate. High fluence rates induced necrosis with inflammatory reaction and absent normal urothelium. Low fluence rates did not provoke inflammation and resulted in apoptotic cell death with preserved urothelial integrity. This could be attributable to faster photobleaching of the photosensitizer in normal urothelium at low fluence rates. CONCLUSIONS: Bladder photodynamic therapy at a low fluence rate minimizes side effects without hampering therapeutic efficacy.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Fotoquimioterapia/efeitos adversos , Fármacos Fotossensibilizantes/efeitos adversos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Ácido Aminolevulínico/efeitos adversos , Animais , Apoptose , Cistectomia , Feminino , Técnicas Imunoenzimáticas , Ratos , Ratos Endogâmicos F344 , Espectrometria de Fluorescência , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/cirurgia
6.
Eur J Pharm Biopharm ; 184: 1-6, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36682510

RESUMO

Photodynamic therapy is a multistage treatment, in which cancerous and precancerous cells are destroyed by light activation of a drug (photosensitizer). For a long time, high cellular uptake of the photosensitizer was an important indication of efficient PDT, while the role of photosensitizer penetration was unexplored. Recently, we have demonstrated that nanosponges based on hypercrosslinked ß-cyclodextrin polymer (ß-CDp) can increase drug penetration at the cost of their cellular uptake in multicellular spheroids, paving the way for studying the impact of penetration on PDT response. In the present work, we used ß-CDp nanosponges to deliver temoporfin to the depth of stroma-rich head and neck cancer multicellular spheroids and then assess PDT response. Encapsulation of temoporfin in ß-CDp nanosponges resulted in increased penetration and more uniform distribution of temoporfin in spheroids, however, was also associated with a two-fold reduction of cellular uptake compared to the free drug. Nevertheless, we demonstrated that ß-CDp nanosponges possess similar PDT efficiency as the free drug in stroma-rich head and neck cancer multicellular spheroids. Overall, this study suggests that ß-CDp nanosponges are a strong candidate for in vivo studies as they have fewer "off-target" effects while providing a similar therapeutic response.


Assuntos
Neoplasias de Cabeça e Pescoço , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes , Fotoquimioterapia/métodos , Mesoporfirinas , Polímeros
7.
Int J Nanomedicine ; 18: 6545-6562, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965282

RESUMO

Purpose: The tumor microenvironment (TME) is composed of various stromal components, including immune cells such as tumor-associated macrophages (TAMs), which play a crucial role in cancer initiation and progression. TAMs can exhibit either a tumor-suppressive M1 or a tumor-promoting M2 phenotype. First, we aimed to develop a 3D human heterotypic model consisting of head and neck squamous cell carcinoma (HNSCC) cells and different subtypes of macrophages to replicate the interactions between immune cells and cancer cells. We further investigated the behavior of Foslip®, a liposomal formulation of temoporfin, using a macrophage-enriched 3D model. Methods: Monocytes were differentiated into M1 and M2 macrophages, which represent two distinct subtypes. Following histological and molecular characterization, these macrophages were used to establish a 3D spheroid model of HNSCC enriched with either polarized macrophages or conditioned media. Flow cytometry and fluorescence microscopy were used to assess the accumulation and distribution of Foslip®. The cytotoxic effect of Foslip®-mediated photodynamic therapy (PDT) was evaluated using flow cytometry. Results: We developed heterotypic spheroids characterized by a mixed phenotype of evenly distributed macrophages. In this 3D co-culture model, both M1 and M2 macrophages showed significantly higher accumulation of Foslip® compared to the cancer cells. Although this differential accumulation did not drastically affect the overall PDT efficiency, spheroids generated with conditioned media exhibited a significant enhancement in photo-induced cell death, suggesting that the microenvironment could modulate the response to Foslip®-PDT. Conclusion: 3D models of HNSCC cells and macrophages provide valuable insights into the complex response of HNSCC cells to PDT using Foslip® in vitro. This model can be used to screen immunomodulatory nanomedicines targeting TAMs in solid head and neck tumors, either alone or in combination with standard therapies.


Assuntos
Neoplasias de Cabeça e Pescoço , Microambiente Tumoral , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Meios de Cultivo Condicionados/farmacologia , Macrófagos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Linhagem Celular Tumoral
8.
Macromol Biosci ; 23(3): e2200434, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36448191

RESUMO

Ovarian cancer remains a major public health issue due to its poor prognosis. To develop more effective therapies, it is crucial to set-up reliable models that closely mimic the complexity of the ovarian tumor's microenvironment. 3D bioprinting is currently a promising approach to build heterogenous and reproducible cancer models with controlled shape and architecture. However, this technology is still poorly investigated to model ovarian tumors. In this study, a 3D bioprinted ovarian tumor model combining cancer cells (SKOV-3) and cancer associated fibroblasts (CAFs) are described. The resulting tumor models show their ability to maintain cell viability and proliferation. Cells are observed to self-assemble in heterotypic aggregates. Moreover, CAFs are observed to be recruited and to circle cancer cells reproducing an in vivo process taking place in the tumor microenvironment. Interestingly, this approach also shows its ability to rapidly generate a high number of reproducible tumor models that can be subjected to usual characterizations (cell viability and metabolic activity; histology and immunological studies; and real-time imaging). Therefore, these ovarian tumor models can be an interesting tool for high throughput drug screening applications.


Assuntos
Bioimpressão , Fibroblastos Associados a Câncer , Neoplasias Ovarianas , Feminino , Humanos , Técnicas de Cocultura , Fibroblastos Associados a Câncer/patologia , Neoplasias Ovarianas/patologia , Linhagem Celular Tumoral , Esferoides Celulares/patologia , Microambiente Tumoral
9.
BJU Int ; 110(11 Pt C): E1155-62, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22883132

RESUMO

UNLABELLED: What's known on the subject? and What does the study add? Fluorescence cystoscopy with hexylaminolevulinate (h-ALA, Hexvix®) is known to improve tumour detection in non-muscle-invasive bladder cancer. However, specificity is relatively low and the intensity of the observed fluorescence signal decreases over time due to protoporphyrin IX (PpIX) efflux. This study evaluates in an in vivo model the use of a dendritic 5-aminolevulinic acid compound for fluorescence diagnosis. Fluorescence ratios between tumour and urothelium as well as muscle were significantly better as compared with h-ALA. Sustained synthesis of PpIX accounts for preservation of fluorescence for >24 h. OBJECTIVE: • To overcome the relative lack of tumour selectivity of fluorescence-guided cystoscopy using 5-aminolevulinic acid (ALA) or its ester derivative (e.g. hexylaminolevulinate, h-ALA; Hexvix®), we evaluated the use of dendrimers bearing different ALA loads in rats bearing orthotopic bladder tumours. MATERIALS AND METHODS: • Rat bladders were instilled with h-ALA or ALA dendrimers and fluorescence ratio between tumour and normal urothelium, as well as tumour and muscle and depth of fluorescence were determined with Image J software. • Quantification of ALA and/or esters systemic reabsorption was evaluated by high-performance liquid chromatography. RESULTS: • Slow hydrolysis of ALA from dendrimers as observed in vitro implies a higher initial ALA load and longer resting times in vivo. Sustained synthesis of protoporphyrin IX (PpIX) explains persistence of fluorescence for >24 h. • There were significantly better fluorescence ratios with dendrimers, as well as higher penetration depths and absence of systemic reabsorption. CONCLUSION: • The prolonged and sustained PpIX synthesis, the improved tumour selectivity with a deeper penetration and the absence of systemic reabsorption are primary indicators that ALA dendrimers could be an alternative to h-ALA in fluorescence-guided cystoscopy.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Dendrímeros , Microscopia de Fluorescência/métodos , Neoplasias Experimentais , Neoplasias da Bexiga Urinária/diagnóstico , Administração Intravesical , Ácido Aminolevulínico/administração & dosagem , Ácido Aminolevulínico/farmacocinética , Animais , Dendrímeros/administração & dosagem , Dendrímeros/farmacocinética , Feminino , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacocinética , Ratos , Ratos Endogâmicos F344 , Reprodutibilidade dos Testes , Neoplasias da Bexiga Urinária/metabolismo
10.
Pharmaceutics ; 14(10)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36297571

RESUMO

Quantum Dots (QDs) are fluorescent nanoparticles known for their exceptional optical properties, i.e., high fluorescence emission, photostability, narrow emission spectrum, and broad excitation wavelength. These properties make QDs an exciting choice for bioimaging applications, notably in cancer imaging. Challenges lie in their ability to specifically label targeted cells. Numerous studies have been carried out with QDs coupled to various ligands like peptides, antibodies, aptamers, etc., to achieve efficient targeting. Most studies were conducted in vitro with two-dimensional cell monolayers (n = 8902) before evolving towards more sophisticated models. Three-dimensional multicellular tumor models better recapitulate in vivo conditions by mimicking cell-to-cell and cell-matrix interactions. To date, only few studies (n = 34) were conducted in 3D in vitro models such as spheroids, whereas these models could better represent QDs behavior in tumors compared to monolayers. Thus, the purpose of this review is to present a state of the art on the studies conducted with Quantum Dots on spheroid models for imaging and phototherapy purposes.

11.
Photodiagnosis Photodyn Ther ; 37: 102636, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34808398

RESUMO

BACKGROUND: The efficient intraoperative identification of tumors requires the development of highly specific near-infrared (NIR) probes as contrast agents. One of the most effective dyes existing in clinic oncology is Indocyanine Green (ICG). However, ICG has a rapid excretion, thus ruling out its extended accumulation in pathological tissues therefore limiting its clinical applications. ICG colloid solution (ICG NPs) consists predominantly of J-aggregates and to a lesser extent of H-aggregates and monomers. In the present study we assessed the spectral properties of ICG nanoforms in preclinical models. METHODS: We used optical spectroscopy and video fluorescence navigation to monitor accumulation and distribution of ICG monomers and ICG NPs in various tissues in mice with xenografted laryngopharyngeal carcinoma after intravenous drugs injection. RESULTS: After i.v. injection, the molecular form of ICG was not retained in the tumor and its circulation cycle averaged 5 min. Alternatively, the nanoform of the drug had a different pharmacokinetics, reaching maximum accumulation 24 h after intravenous injection. Moreover, once in the circulation, we observed a progressive accumulation in the tumor of both ICG H-aggregates and ICG monomers, but not J-aggregates. CONCLUSION: Spectral characteristics of ICG NPs indicated the presence of several fractions, namely, J- and H-aggregates along with molecular forms. These fractions had different fluorescence spectra, allowing us to track the transformation of the drug in vivo conditions. After ICG NPs administration, J-aggregates induce accumulation of monomeric forms in the tumor, enabling extended intraoperative diagnostic, and as such further studies of J-aggregates for theranostic applications in oncological surgery are of great interest.


Assuntos
Verde de Indocianina , Fotoquimioterapia , Animais , Corantes , Corantes Fluorescentes/farmacologia , Verde de Indocianina/farmacocinética , Camundongos , Imagem Óptica/métodos , Fotoquimioterapia/métodos
12.
Biomedicines ; 10(3)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35327351

RESUMO

Previous studies have found that use of hexaminolevulinate (HAL) and blue light cystoscopy (BLC) during treatment of bladder cancer had a positive impact on overall survival after later cystectomy, indicating a potential treatment effect beyond improved diagnostic accuracy. The aim of our study was to determine whether HAL and BL mimicking clinically relevant doses in an orthotopic rat model could have therapeutic effect by inducing modulation of a tumor-specific immune response. We also assessed whether administration with a checkpoint inhibitor could potentiate any effects observed. Rats were subjected to HAL BL alone and in combination with anti-PD-L1 and assessed for anti-tumor effects and effects on immune markers. Positive anti-tumor effect was observed in 63% and 31% of rats after, respectively, 12 and 30 days after the procedure, together with a localization effect of CD3+ and CD8+ cells after 30 days. Anti-tumor effect at 30 days increases from 31% up to 38% when combined with intravesical anti-PD-L1. In conclusion, our study demonstrated treatment effects with indications of systemic immune activation at diagnostic doses of HAL and blue light. The observed treatment effect seemed to be enhanced when used in combination with intravesically administrated immune checkpoint inhibitor.

13.
Rapid Commun Mass Spectrom ; 25(13): 1881-92, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21638364

RESUMO

Peptide Mass Fingerprinting (PMF) is still of significant interest in proteomics because it allows a large number of complex samples to be rapidly screened and characterized. The main part of post-translational modifications is generally preserved. In some specific cases, PMF suffers from ambiguous or unsuccessful identification. In order to improve its reliability, a combined approach using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICRMS) was evaluated. The study was carried out on bovine serum albumin (BSA) digest. The influence of several important parameters (the matrix, the sample preparation method, the amount of the analyte) on the MOWSE score and the protein sequence coverage were evaluated to allow the identification of specific effects. A careful investigation of the sequence coverage obtained by each kind of experiment ensured the detection of specific peptides for each experimental condition. Results highlighted that DHB-FTICRMS and DHB- or CHCA-TOFMS are the most suited combinations of experimental conditions to achieve PMF analysis. The association (convolution) of the data obtained by each of these techniques ensured a significant increase in the MOWSE score and the protein sequence coverage.


Assuntos
Mapeamento de Peptídeos/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sequência de Aminoácidos , Animais , Bovinos , Ácidos Cumáricos/química , Análise de Fourier , Gentisatos/química , Dados de Sequência Molecular , Peso Molecular , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo
14.
Photochem Photobiol Sci ; 10(6): 911-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21311777

RESUMO

We used the phenomenon of previously described photoinduced fluorescence quenching and fluorescence polarization to evaluate the transfer of meta-tetra(hydroxyphenyl)chlorin (m-THPC) from commercial high-drug load liposomes to plasma proteins and model membranes. Fluorescence quenching of m-THPC in liposomes by iodide indicates that part of m-THPC in PEGylated liposomes is localized in the PEG shell, while the rest is bound to the lipid bilayer. It was shown that the two molecule pools in the commercial PEGylated liposomal formulation Fospeg® condition the characteristics of the m-THPC release kinetics. A substantial percentage of m-THPC from Fospeg® is released much faster than from the conventional liposomal formulation Foslip®. Using the technique of resonance light scattering, it was shown that partial m-THPC aggregation is present in liposomes with very high drug loads, higher in PEGylated liposomes compared to conventional ones.


Assuntos
Mesoporfirinas/química , Fármacos Fotossensibilizantes/química , Polietilenoglicóis/química , Proteínas Sanguíneas/química , Química Farmacêutica , Humanos , Cinética , Luz , Lipossomos , Espalhamento de Radiação , Temperatura , Termodinâmica
15.
Nanomaterials (Basel) ; 11(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34947534

RESUMO

Spectroscopic approach with fluorescence time resolution allows one to determine the state of a brain tumor and its microenvironment via changes in the fluorescent dye's fluorescence lifetime. Indocyanine green (ICG) is an acknowledged infra-red fluorescent dye that self-assembles into stable aggregate forms (ICG NPs). ICG NPs aggregates have a tendency to accumulate in the tumor with a maximum accumulation at 24 h after systemic administration, enabling extended intraoperative diagnostic. Fluorescence lifetime analysis of ICG and ICG NPs demonstrates different values for ICG monomers and H-aggregates, indicating promising suitability for fluorescent diagnostics of brain tumors due to their affinity to tumor cells and stability in biological tissue.

16.
Pharmaceutics ; 13(7)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34371745

RESUMO

Photodynamic therapy represents a more targeted and less invasive alternative cancer treatment to traditional modalities. Temoporfin, as with many photosensitizers, is given by injection into a vein, and its subsequent fate is largely determined by the binding to plasma proteins and interaction with endothelial and blood cells. Thus, it is essential to be able to control and to alter the biodistribution of temoporfin in blood. In the present study, we evaluated the effect of co-administration of temoporfin with randomly methylated ß-CD (Me-ß-CD) on the distribution of temoporfin in the main subpopulations of blood cells of healthy donors using absorbance spectrophotometry and flow cytometry. We showed that cell-bound temoporfin fraction in blood strongly depends on the concentration of Me-ß-CD. In fact, the accumulation of temoporfin in white blood cells was more sensitive than that in red blood cells, due to the higher volume of membranous organelles in white blood cells. Finally, we demonstrated that Me-ß-CD significantly increases cellular uptake of temoporfin cancer human Burkitt's lymphoma Raji cells. The presence of Me-ß-CD resulted in a spotted pattern of temoporfin distribution in the plasma membrane compartment. Our results clearly demonstrated that ß-CDs derivatives provide new options to modulate temoporfin biodistribution in blood.

17.
Clin Epigenetics ; 13(1): 212, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34852845

RESUMO

BACKGROUND: Although radiation therapy represents a core cancer treatment modality, its efficacy is hampered by radioresistance. The effect of ionizing radiations (IRs) is well known regarding their ability to induce genetic alterations; however, their impact on the epigenome landscape in cancer, notably at the CpG dinucleotide resolution, remains to be further deciphered. In addition, no evidence is available regarding the effect of IRs on the DNA methylome profile according to the methionine dependency phenotype, which represents a hallmark of metabolic adaptation in cancer. METHODS: We used a case-control study design with a fractionated irradiation regimen on four cancerous cell lines representative of HCC (HepG2), melanoma (MeWo and MeWo-LC1, which exhibit opposed methionine dependency phenotypes), and glioblastoma (U251). We performed high-resolution genome-wide DNA methylome profiling using the MethylationEPIC BeadChip on baseline conditions, irradiated cell lines (cumulative dose of 10 Gy), and non-irradiated counterparts. We performed epigenome-wide association studies to assess the effect of IRs and methionine-dependency-oriented analysis by carrying out epigenome-wide conditional logistic regression. We looked for epigenome signatures at the locus and single-probe (CpG dinucleotide) levels and through enrichment analyses of gene ontologies (GO). The EpiMet project was registered under the ID#AAP-BMS_003_211. RESULTS: EWASs revealed shared GO annotation pathways associated with increased methylation signatures for several biological processes in response to IRs, including blood circulation, plasma membrane-bounded cell projection organization, cell projection organization, multicellular organismal process, developmental process, and animal organ morphogenesis. Epigenome-wide conditional logistic regression analysis on the methionine dependency phenotype highlighted several epigenome signatures related to cell cycle and division and responses to IR and ultraviolet light. CONCLUSIONS: IRs generated a variation in the methylation level of a high number of CpG probes with shared biological pathways, including those associated with cell cycle and division, responses to IRs, sustained angiogenesis, tissue invasion, and metastasis. These results provide insight on shared adaptive mechanisms of the epigenome in cancerous cell lines in response to IR. Future experiments should focus on the tryptic association between IRs, the initiation of a radioresistance phenotype, and their interaction with methionine dependency as a hallmark of metabolic adaptation in cancer.


Assuntos
Adaptação Psicológica , Linhagem Celular Tumoral/efeitos da radiação , Metionina/efeitos adversos , Radiação Ionizante , Metilação de DNA/genética , Metilação de DNA/imunologia , Epigenômica/métodos , Epigenômica/estatística & dados numéricos , Humanos , Metionina/metabolismo
18.
Sci Rep ; 10(1): 21273, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33277538

RESUMO

Radiation-induced fibrosis (RIF) is the main late radiation toxicity in breast cancer patients. Most of the current 3D in vitro breast cancer models are composed by cancer cells only and are unable to reproduce the complex cellular homeostasis within the tumor microenvironment to study RIF mechanisms. In order to account complex cellular interactions within the tumor microenvironment, an advanced 3D spheroid model, consisting of the luminal breast cancer MCF-7 cells and MRC-5 fibroblasts, was developed. The spheroids were generated using the liquid overlay technique in culture media into 96-well plates previously coated with 1% agarose (m/v, in water). In total, 21 experimental setups were tested during the optimization of the model. The generated spheroids were characterized using fluorescence imaging, immunohistology and immunohistochemistry. The expression of ECM components was confirmed in co-culture spheroids. Using α-SMA staining, we confirmed the differentiation of healthy fibroblasts into myofibroblasts upon the co-culturing with cancer cells. The induction of fibrosis was studied in spheroids treated 24 h with 10 ng/mL TGF-ß and/or 2 Gy irradiation. Overall, the developed advanced 3D stroma-rich in vitro model of breast cancer provides a possibility to study fibrosis mechanisms taking into account 3D arrangement of the complex tumor microenvironment.


Assuntos
Neoplasias da Mama , Técnicas de Cocultura , Modelos Biológicos , Humanos , Células MCF-7 , Esferoides Celulares , Células Tumorais Cultivadas
19.
Eur J Pharm Biopharm ; 154: 33-42, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32634570

RESUMO

As the intertissue delivery of hydrophobic temoporfin (mTHPC) remains inefficient, we propose the use of cyclodextrin-based nanosponges as a smart, advanced system for improved mTHPC delivery. Recently, we demonstrated that cyclodextrins (CDs) allow mTHPC to penetrate into tumor spheroids via a nanoshuttle mechanism. However, the CD complexes were very sensitive to the dilution, thus limiting their translation invivo. Hypercrosslinked CD monomers in a three-dimensional network (namely, CD nanosponges), however, may form both inclusion and non-inclusion complexes with drug molecules, providing controlled release and prolonged exposure to the drug. In the present work, we demonstrate that epichlorohydrin-crosslinked CD nanosponges based on ß-CD (ßCDp) and carboxymethyl-ß-CD (CMßCDp) monomers efficiently encapsulated mTHPC. We calculated the apparent binding constants between mTHPC and CD polymers (K=(6.3-8.8) × 106M-1 and K=(1.2-1.7) × 106M-1 for ßCDp and CMßCDp, respectively) using fluorescence titration curve fitting. The encapsulation of mTHPC in a CD polymer matrix had slower photosensitizer (PS) release compared to monomer CD units, providing deep penetration of mTHPC in 3D tumor spheroids in a concentration-dependent manner. However, the improvement of mTHPC penetration in 3D human pharynx squamous cell carcinoma (FaDu) spheroids using CD polymers was strongly accompanied by the inhibition of PS cellular uptake, demonstrating the delicate balance between the accumulation and the penetration of PS in FaDu spheroids. In summary, mTHPC-loaded CD nanosponges are a strong candidate for further invivo study in preclinical models, which could be considered as an advanced smart system for mTHPC delivery.


Assuntos
Ciclodextrinas/administração & dosagem , Portadores de Fármacos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/administração & dosagem , Esferoides Celulares/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Ciclodextrinas/metabolismo , Portadores de Fármacos/metabolismo , Humanos , Nanopartículas/metabolismo , Esferoides Celulares/metabolismo
20.
Cancers (Basel) ; 12(12)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322532

RESUMO

The efficient intraoperative identification of cancers requires the development of the bright, minimally-toxic, tumor-specific near-infrared (NIR) probes as contrast agents. Luminescent semiconductor quantum dots (QDs) offer several unique advantages for in vivo cellular imaging by providing bright and photostable fluorescent probes. Here, we present the synthesis of ZnCuInSe/ZnS core/shell QDs emitting in NIR (~750 nm) conjugated to NAVPNLRGDLQVLAQKVART (A20FMDV2) peptide for targeting αvß6 integrin-rich head and neck squamous cell carcinoma (HNSCC). Integrin αvß6 is usually not detectable in nonpathological tissues, but is highly upregulated in HNSCC. QD-A20 showed αvß6 integrin-specific binding in two-dimension (2D) monolayer and three-dimension (3D) spheroid in vitro HNSCC models. QD-A20 exhibit limited penetration (ca. 50 µm) in stroma-rich 3D spheroids. Finally, we demonstrated the potential of these QDs by time-gated fluorescence imaging of stroma-rich 3D spheroids placed onto mm-thick tissue slices to mimic imaging conditions in tissues. Overall, QD-A20 could be considered as highly promising nanoprobes for NIR bioimaging and imaging-guided surgery.

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