A carregar...
Projeto de investigação
Novel nanoplatforms for targeting melanoma with 8-hydroxyquinoline metal complexes
Financiador
Autores
Publicações
Gold nanoparticles for photothermal therapy – Influence of experimental conditions on the properties of resulting AuNPs
Publication . Amaral, Mariana Neves; Nunes, Daniela; Fortunato, Elvira; Martins, Rodrigo; Rodrigues, Carla; Faísca, Pedro; Ferreira, Hugo Alexandre; Coelho, João M.P.; Gaspar, M. Manuela; Reis, Catarina Pinto; Faculdade de Ciências e Tecnologia (FCT); DCM - Departamento de Ciência dos Materiais; CENIMAT-i3N - Centro de Investigação de Materiais (Lab. Associado I3N); DQ - Departamento de Química; CQFB-REQUIMTE - Centro de Química Fina e Biotecnologia (Lab. Associado REQUIMTE); Editions de Sante
Gold nanoparticles (AuNPs)-mediated Photothermal Therapy (PTT) is a minimally-invasive therapeutic approach that uses AuNPs to convert light into heat, leading to the thermal ablation of tumors. Thus, the efficacy of this strategy strongly relies on the photothermal conversion potential of AuNPs. The ability to convert light into heat can be enhanced by tuning the physicochemical and optical properties of AuNPs. This can be achieved by changing the conditions of AuNP's synthesis, such as the order of addition of reagents. The present work entails to explore how varying the order of reagents addition modulates the properties of AuNPs, particularly enhancing the photothermal conversion potential of the resulting AuNPs and consequently, improving PTT efficacy. For this, eleven different AuNPs' nanoformulations were synthetized following different sequences of addition of reagents. These nanoformulations were characterized regarding their physicochemical properties namely size, surface charge, gold concentration, surface morphology and maximum absorbance wavelength. In addition, their thermal activation profiles were determined in vitro. Furthermore, the biocompatibility of different nanoformulations was also assessed. Three nanoformulations, with the most favorable photothermal activation profiles (AuNPs 2, 3 and 7), were then selected for preliminary in vitro safety and efficacy assays using a panel of cell lines. These three nanoformulations were deemed safe in vitro at the tested concentrations. At 250 μM of gold content, and after an incubation period of 4 h, followed by 5 min irradiation with a laser emitting at 808 nm (7.96 W/cm2), AuNPs 7 significantly reduced the cell viability of all cancer cell lines tested (MCF-7, HCT-116 and A375) by ≥ 45 %. However, such cytotoxic effect was not observed for the human keratinocyte cell line (HaCat), thus demonstrating its specificity towards cancer cells. Overall, the results herein presented reinforce that the order of reagents addition is highly important for achieving adequate AuNPs for PTT.
Liposomal nanoformulations of novel copper-based complexes exhibiting antimelanoma activity – In vitro and in vivo validation
Publication . Coelho, Mariana P.; Farinha, Pedro F.; Côrte-Real, Leonor; Ribeiro, Nádia; Luiz, Hugo; Pinho, Jacinta O.; Noiva, Rute; Godinho-Santos, Catarina; Reis, Catarina Pinto; Correia, Isabel; Gaspar, Maria Manuela; CENIMAT-i3N - Centro de Investigação de Materiais (Lab. Associado I3N); DCM - Departamento de Ciência dos Materiais; Elsevier
Melanoma stands as the most aggressive form of skin cancer. The lack of effective and safe therapies has led to the investigation of innovative strategies. The present work validates the in vitro and in vivo antimelanoma activity of new copper complexes of 8-hydroxyquinoline (8HQ) derivatives in free or liposomal forms. Firstly, the cytotoxic properties of several copper-based complexes were screened towards human (A375) and murine (B16F10) melanoma cell lines and human dermal fibroblasts or keratinocytes (HaCaT) cell lines. All the complexes presented lower IC50 values (<20 μM) than dacarbazine (DTIC) and temozolomide (TMZ), the positive controls (>80 μM). Aiming to solve low specificity against tumor cells and enhance its targetability to affected sites three metal-based complexes were selected, based on their antiproliferative properties, and incorporated in long blood circulating liposomes. One of them, di-2-(((2-morpholinoethyl)imino)methyl)quinolin-8-olCopper(II), designated as LCR35, was selected for further studies due to the highest incorporation parameters and cytotoxic properties observed. The antiproliferative activity of LCR35 was preserved after its association to liposomes. Moreover, in B16F10 cells this effect was potentiated. Furthermore, cell cycle analysis studies in A375 and B16F10 cell lines were performed to elucidate the mechanism of action of copper-based complex formulations. A cell cycle arrest at G2/M and G0/G1 phases in A375 and B16F10 cells, respectively, both in free and liposomal forms were observed. To validate the therapeutic potential of LCR35 two murine melanoma models were carried out: subcutaneous and metastatic. Pre-clinical studies demonstrated the high therapeutic effect of LCR35, especially after incorporation in liposomes, compared to control group or animals that received LCR35 Free and DTIC. Overall, in vitro and in vivo studies highlight the potential antimelanoma properties of the copper-based complex, LCR35.
Solution chemical properties and anticancer potential of 8-hydroxyquinoline hydrazones and their oxidovanadium(IV) complexes
Publication . Ribeiro, Nádia; Bulut, Ipek; Pósa, Vivien; Sergi, Baris; Sciortino, Giuseppe; Pessoa, João Costa; Maia, Luísa B.; Ugone, Valeria; Garribba, Eugenio; Enyedy, Éva A.; Acilan, Ceyda; Correia, Isabel; LAQV@REQUIMTE; Elsevier
We report the synthesis and characterization of a family of benzohydrazones (Ln, n = 1–6) derived from 2-carbaldehyde-8-hydroxyquinoline and benzylhydrazides containing different substituents in the para position. Their oxidovanadium(IV) complexes were prepared and compounds with 1:1 and 1:2 metal-to-ligand stoichiometry were obtained. All compounds were characterized by elemental analyses and mass spectrometry as well as FTIR, UV–visible absorption, NMR (ligand precursors) and EPR (complexes) spectroscopies, and by DFT computational methods. Proton dissociation constants, lipophilicity and solubility in aqueous media were determined for all ligand precursors. Complex formation with V(IV)O was evaluated by spectrophotometry for L4 (Me-substituted) and L6 (OH-substituted) and formation constants for mono [VO(HL)]+, [VO(L)] and bis [VO(HL)2], [VO(HL)(L)]−, [VO(L)2]2− complexes were determined. EPR spectroscopy indicates the formation of [VO(HL)]+ and [VO(HL)2], with this latter being the major species at the physiological pH. Noteworthy, the EPR data suggest a different behaviour for L4 and L6, which confirm the results obtained in the solid state. The antiproliferative activity of all compounds was evaluated in malignant melanoma (A-375) and lung (A-549) cancer cells. All complexes show much higher activity on A-375 (IC50 < 6.3 μM) than in A-549 cells (IC50 > 20 μM). Complex 3 (F-substituted) shows the lowest IC50 on both cell lines and lower than cisplatin (in A-375). Studies identified this compound as the one showing the highest increase in Annexin-V staining, caspase activity and induction of double stranded breaks, corroborating the cytotoxicity results. The mechanism of action of the complexes involves reactive oxygen species (ROS) induced DNA damage, and cell death by apoptosis.
An alternative hybrid lipid nanosystem combining cytotoxic and magnetic properties as a tool to potentiate antitumor effect of 5-fluorouracil
Publication . Azevedo, Afonso; Coelho, Mariana P.; Pinho, Jacinta O.; Soares, Paula I. P.; Reis, Catarina P.; Borges, João P.; Gaspar, M. Manuela; DCM - Departamento de Ciência dos Materiais; CENIMAT-i3N - Centro de Investigação de Materiais (Lab. Associado I3N); Elsevier Science B.V., Amsterdam.
Aims: Colorectal cancer is the third most frequent type of cancer and the second leading cause of cancer-related deaths worldwide. The majority of cases are diagnosed at a later stage, leading to the need for more aggressive treatments such as chemotherapy. 5-Fluorouracil (5-FU), known for its high cytotoxic properties has emerged as a chemotherapeutic agent. However, it presents several drawbacks such as lack of specificity and short half-life. To reduce these drawbacks, several strategies have been designed namely chemical modification or association to drug delivery systems. Materials and methods: Current research was focused on the design, physicochemical characterization and in vitro evaluation of a lipid-based system loaded with 5-FU. Furthermore, aiming to maximize preferential targeting and release at tumour sites, a hybrid lipid-based system, combining both therapeutic and magnetic properties was developed and validated. For this purpose, liposomes co-loaded with 5-FU and iron oxide (II, III) nanoparticles were accomplished. Key findings: The characterization of the developed nanoformulation was performed in terms of incorporation parameters, mean size and surface charge. In vitro studies assessed in a murine colon cancer cell line confirmed that 5-FU antiproliferative activity was preserved after incorporation in liposomes. In same model, iron oxide (II, III) nanoparticles did not exhibit cytotoxic properties. Additionally, the presence of these nanoparticles was shown to confer magnetic properties to the liposomes, allowing them to respond to external magnetic fields. Significance: Overall, a lipid nanosystem loading a chemotherapeutic agent displaying magnetic characteristics was successfully designed and physicochemically characterized, for further in vivo applications.
Nanoformulations of novel metal-complexes as potential antitumor agents
Publication . Teixeira, Melissa Daniela Albino; Gaspar, Maria Manuela; Reis, Catarina Pinto; Barral, Duarte C.
RESUMO: O cancro colorretal é a segunda causa de mortalidade na oncologia. As terapias atuais baseadas em
quimioterapia apresentam perfis de biodistribuição ineficientes e reduzida especificidade. Consequentemente,
há uma falta de resposta à terapêutica que culmina na progressão da doença, em baixas taxas de sobrevivência
e numa diminuição na qualidade de vida. O uso da cisplatina despertou o interesse para o potencial dos
compostos metálicos. No entanto, estes também estão associados a baixa seletividade e solubilidade em água.
O uso de lipossomas pode ultrapassar estas desvantagens, melhorando a solubilidade dos compostos, a eficácia
terapêutica e diminuindo efeitos secundários. Além disso, os lipossomas podem permanecer na corrente
sanguínea por longos períodos de tempo, extravasando e acumulando em regiões de alta permeabilidade
vascular, tais como regiões tumorais. Adicionalmente, o microambiente dos tumores sólidos é ligeiramente
ácido, contrastando com os tecidos saudáveis. Os lipossomas também podem incluir lípidos sensíveis ao pH
capazes de induzir uma libertação controlada dos compostos incorporados quando alcançam locais acídicos.
O objetivo deste projeto consistiu no desenvolvimento de um sistema de base lipídica, lipossomas,
incorporando eficientemente um novo composto metálico, com tempos de circulação na corrente sanguínea
elevados e com sensibilidade ao pH, capaz de promover uma vectorização para os locais tumorais.
Para isto, vários compostos metálicos foram analisados in vitro utilizando linhas celulares tumorais humanas
e murinas, assim como uma linha não tumoral, de modo a selecionar o composto mais promissor. De seguida,
formulações lipossomais do composto escolhido foram desenvolvidas e caracterizadas em termos de eficiência
de incorporação, diâmetro médio, potencial zeta e sensibilidade ao pH. O efeito antiproliferativo da formulação
lipossomal escolhida foi avaliado em linhas celulares de cancro do colon, CT-26 e HCT-116 em modelos 2D
e 3D. Além disso, estudos de internalização de lipossomas marcados com uma sonda fluorescente (rodamina)
em esferóides de células de cancro do cólon (3D) foram realizados por microscopia confocal.
Foi selecionado como agente antiproliferativo um composto baseado em zinco. Foram preparados lipossomas
com carga neutra incorporando o composto com uma eficiência de incorporação de 76% com um diâmetro
médio a baixo de 120 nm. Foi também demonstrada a sensibilidade ao pH da formulação desenvolvida. Num
modelo celular 2D, o composto metálico apresentou um IC50 inferior a 15 µM nas suas formas livre e
lipossomal. Os estudos de internalização demonstraram a capacidade dos lipossomas em penetrarem os
esferóides de células de cancro do cólon numa forma dependente da concentração e do tempo de incubação.
De referir que em modelo celular 3D, foram necessárias concentrações mais altas do composto de zinco nas
formas livre e lipossomal para atingir propriedades antiproliferativas comparativamente ao modelo 2D.
Tendo em conta todos os resultados obtidos, a formulação lipossomal deste novo composto metálico
desenvolvida constitui uma abordagem com elevado potencial para o tratamento do cancro colorretal.
Unidades organizacionais
Descrição
Palavras-chave
Contribuidores
Financiadores
Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
3599-PPCDT
Número da atribuição
PTDC/QUI-QIN/0586/2020