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2025
Triazole-Derived Ruthenium(II) Complexes as Novel Candidates for Cancer Therapy, Royo, Beatriz, Lenis-Rojas {Oscar A. }, Roma Catarina, Carvalho Beatriz, Andrade Vasco, Friães Sofia, Cabezas-Sain Pablo, Fernández {Jhonathan Angel Araujo}, Vila {Sabela Fernandez}, Arana {Alvaro J. }, Sanchez Laura, Baptista {Pedro V. }, Gomes {Clara S. B. }, and Fernandes {Alexandra R. } , ChemPlusChem, p.e202400775, (2025) Abstract

The first examples of Ru(II) h6-arene (benzene and p-cymene) complexes containing a bidentate triazolylidene-triazolide ligand have been prepared and fully characterized. Their antiproliferative effect has been investigated against tumour cells A2780 (ovarian carcinoma), HCT116 (colorectal carcinoma), and HCT116dox (colorectal carcinoma resistant to doxorubicin), and in human dermal fibroblasts. The Ru complex bearing the p-cymene arene group exhibited a stronger antiproliferative effect across all tested cell lines, while the benzene-containing complex displayed higher selectivity toward tumor cells. Both complexes induced apoptosis, likely through ROS production (in the benzene complex), and inhibited tumorigenic processes, including cell migration and angiogenesis. In zebrafish models, they showed strong selectivity for cancer cells with minimal toxicity to healthy cells, effectively reducing the proliferation of HCT116 colorectal cancer cells. This study provides the first in vivo evidence of the anticancer potential of Ru triazolylidenes in zebrafish models.

2023
Epidermal growth factor alters silica nanoparticle uptake and improves gold-nanoparticle-mediated gene silencing in A549 cells, Susnik, Eva, Bazzoni Amelie, Taladriz-Blanco Patricia, Balog Sandor, Moreno-Echeverri {Aura Maria}, Glaubitz Christina, {Brito Oliveira} Beatriz, Ferreira Daniela, {Viana Baptista} Pedro, Petri-Fink Alke, and Rothen-Rutishauser Barbara , Frontiers in Nanotechnology, jul, Volume 5, (2023) Abstract

Introduction: Delivery of therapeutic nanoparticles (NPs) to cancer cells represents a promising approach for biomedical applications. A key challenge for nanotechnology translation from the bench to the bedside is the low amount of administered NPs dose that effectively enters target cells. To improve NPs delivery, several studies proposed NPs conjugation with ligands, which specifically deliver NPs to target cells via receptor binding. One such example is epidermal growth factor (EGF), a peptide involved in cell signaling pathways that control cell division by binding to epidermal growth factor receptor (EGFR). However, very few studies assessed the influence of EGF present in the cell environment, on the cellular uptake of NPs. Methods: We tested if the stimulation of EGFR-expressing lung carcinomacells A549 with EGF affects the uptake of 59 nm and 422 nm silica (SiO2) NPs. Additionally, we investigated whether the uptake enhancement can be achieved with gold NPs, suitable to downregulate the expression of cancer oncogene c-MYC. Results: Our findings show that EGF binding to its receptor results in receptor autophosphorylation and initiate signaling pathways, leading to enhanced endocytosis of 59 nm SiO2 NPs, but not 422 nm SiO2 NPs. Additionally, we demonstrated an enhanced gold (Au) NPs endocytosis and subsequently a higher downregulation of c-MYC. Discussion: These findings contribute to a better understanding of NPs uptake in the presence of EGF and that is a promising approach for improved NPs delivery.

In Vitro and In Vivo Biological Activities of Dipicolinate Oxovanadium(IV) Complexes, Choroba, Katarzyna, Filipe Beatriz, Świtlicka Anna, Penkala Mateusz, Machura Barbara, Bieńko Alina, Cordeiro Sandra, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Journal Of Medicinal Chemistry, jul, Volume 66, Number 13, p.8580–8599, (2023) Abstract

The work is focused on anticancer properties of dipicolinate (dipic)-based vanadium(IV) complexes [VO(dipic)(N∩N)] bearing different diimines (2-(1H-imidazol-2-yl)pyridine, 2-(2-pyridyl)benzimidazole, 1,10-phenanthroline-5,6-dione, 1,10-phenanthroline, and 2,2′-bipyridine), as well as differently 4,7-substituted 1,10-phenanthrolines. The antiproliferative effect of V(IV) systems was analyzed in different tumors (A2780, HCT116, and HCT116-DoxR) and normal (primary human dermal fibroblasts) cell lines, revealing a high cytotoxic effect of [VO(dipic)(N∩N)] with 4,7-dimethoxy-phen (5), 4,7-diphenyl-phen (6), and 1,10-phenanthroline (8) against HCT116-DoxR cells. The cytotoxicity differences between these complexes can be correlated with their different internalization by HCT116-DoxR cells. Worthy of note, these three complexes were found to (i) induce cell death through apoptosis and autophagy pathways, namely, through ROS production; (ii) not to be cytostatic; (iii) to interact with the BSA protein; (iv) do not promote tumor cell migration or a pro-angiogenic capability; (v) show a slight in vivo anti-angiogenic capability, and (vi) do not show in vivo toxicity in a chicken embryo.

Open-source tool for real-time and automated analysis of droplet-based microfluidic, Neto, {Joana P. }, Mota Ana, c}alo Lopes Gon{\c, Coelho {Beatriz J. }, Frazão João, Moura {André T. }, Oliveira Beatriz, Sieira Bárbara, Fernandes José, Fortunato Elvira, Martins Rodrigo, Igreja Rui, Baptista {Pedro V. }, and Águas Hugo , Lab On A Chip, jul, Volume 23, Number 14, p.3238–3244, (2023) Abstract

Droplet-based microfluidic technology is a powerful tool for generating large numbers of monodispersed nanoliter-sized droplets for ultra-high throughput screening of molecules or single cells. Yet further progress in the development of methods for the real-time detection and measurement of passing droplets is needed for achieving fully automated systems and ultimately scalability. Existing droplet monitoring technologies are either difficult to implement by non-experts or require complex experimentation setups. Moreover, commercially available monitoring equipment is expensive and therefore limited to a few laboratories worldwide. In this work, we validated for the first time an easy-to-use, open-source Bonsai visual programming language to accurately measure in real-time droplets generated in a microfluidic device. With this method, droplets are found and characterized from bright-field images with high processing speed. We used off-the-shelf components to achieve an optical system that allows sensitive image-based, label-free, and cost-effective monitoring. As a test of its use we present the results, in terms of droplet radius, circulation speed and production frequency, of our method and compared its performance with that of the widely-used ImageJ software. Moreover, we show that similar results are obtained regardless of the degree of expertise. Finally, our goal is to provide a robust, simple to integrate, and user-friendly tool for monitoring droplets, capable of helping researchers to get started in the laboratory immediately, even without programming experience, enabling analysis and reporting of droplet data in real-time and closed-loop experiments.

Hybrid Digital-Droplet Microfluidic Chip for Applications in Droplet Digital Nucleic Acid Amplification: Design, Fabrication and Characterization, Coelho, {Beatriz J. }, Neto {Joana P. }, Sieira Bárbara, Moura {André T. }, Fortunato Elvira, Martins Rodrigo, Baptista {Pedro V. }, Igreja Rui, and Águas Hugo , Sensors, Volume 23, Number 10, (2023) Abstract

Microfluidic-based platforms have become a hallmark for chemical and biological assays, empowering micro- and nano-reaction vessels. The fusion of microfluidic technologies (digital microfluidics, continuous-flow microfluidics, and droplet microfluidics, just to name a few) presents great potential for overcoming the inherent limitations of each approach, while also elevating their respective strengths. This work exploits the combination of digital microfluidics (DMF) and droplet microfluidics (DrMF) on a single substrate, where DMF enables droplet mixing and further acts as a controlled liquid supplier for a high-throughput nano-liter droplet generator. Droplet generation is performed at a flow-focusing region, operating on dual pressure: negative pressure applied to the aqueous phase and positive pressure applied to the oil phase. We evaluate the droplets produced with our hybrid DMF–DrMF devices in terms of droplet volume, speed, and production frequency and further compare them with standalone DrMF devices. Both types of devices enable customizable droplet production (various volumes and circulation speeds), yet hybrid DMF–DrMF devices yield more controlled droplet production while achieving throughputs that are similar to standalone DrMF devices. These hybrid devices enable the production of up to four droplets per second, which reach a maximum circulation speed close to 1540 µm/s and volumes as low as 0.5 nL.

2022
Antiproliferative Activity of Buddleja saligna (Willd.) against Melanoma and In Vivo Modulation of Angiogenesis, Twilley, Danielle, Thipe {Velaphi C. }, Kishore Navneet, Bloebaum Pierce, Roma-Rodrigues Catarina, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Selepe {Mamoalosi A. }, Langhansova Lenka, Katti Kattesh, and Lall Namrita , Pharmaceuticals, nov, Volume 15, Number 12, (2022) Abstract

Melanoma cells secrete pro-angiogenic factors, which stimulates growth, proliferation and metastasis, and therefore are key therapeutic targets. Buddleja saligna (BS), and an isolated triterpenoid mixture (DT-BS-01) showed a fifty percent inhibitory concentration (IC50) of 33.80 ± 1.02 and 5.45 ± 0.19 µg/mL, respectively, against melanoma cells (UCT-MEL-1) with selectivity index (SI) values of 1.64 and 5.06 compared to keratinocytes (HaCat). Cyclooxygenase-2 (COX-2) inhibition was observed with IC50 values of 35.06 ± 2.96 (BS) and 26.40 ± 4.19 µg/mL (DT-BS-01). BS (30 µg/mL) significantly inhibited interleukin (IL)-6 (83.26 ± 17.60%) and IL-8 (100 ± 0.2%) production, whereas DT-BS-01 (5 µg/mL) showed 51.07 ± 2.83 (IL-6) and 0 ± 6.7% (IL-8) inhibition. Significant vascular endothelial growth factor (VEGF) inhibition, by 15.84 ± 4.54 and 12.21 ± 3.48%, respectively, was observed. In the ex ovo chick embryo yolk sac membrane assay (YSM), BS (15 µg/egg) significantly reduced new blood vessel formation, with 53.34 ± 11.64% newly formed vessels. Silver and palladium BS nanoparticles displayed noteworthy SI values. This is the first report on the significant anti-angiogenic activity of BS and DT-BS-01 and should be considered for preclinical trials as there are currently no US Food and Drug Administration (FDA) approved drugs to inhibit angiogenesis in melanoma.

In Vitro and In Vivo Biological Activity of Ruthenium 1,10-Phenanthroline-5,6-dione Arene Complexes, Lenis-Rojas, {Oscar A. }, Roma-Rodrigues Catarina, Carvalho Beatriz, Cabezas-Sainz Pablo, {Fernández Vila} Sabela, Sánchez Laura, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Royo Beatriz , International Journal of Molecular Sciences, nov, Volume 23, Number 21, (2022) Abstract

Ruthenium(II) arene complexes exhibit promising chemotherapeutic properties. In this study, the effect of the counter anion in Ru(II) complexes was evaluated by analyzing the biological effect of two Ru(II) p-cymene derivatives with the 1,10-phenanthroline-5,6-dione ligand of general-formula [(η6-arene)Ru(L)Cl][X] X = CF3SO3 (JHOR10) and PF6 (JHOR11). The biological activity of JHOR10 and JHOR11 was examined in the ovarian carcinoma cell line A2780, colorectal carcinoma cell line HCT116, doxorubicin-resistant HCT116 (HCT116-Dox) and in normal human dermal fibroblasts. Both complexes JHOR10 and JHOR11 displayed an antiproliferative effect on A2780 and HCT116 cell lines, and low cytotoxicity in fibroblasts. Interestingly, JHOR11 also showed antiproliferative activity in the HCT116-Dox cancer cell line, while JHOR10 was inactive. Studies in A2780 cells showed that JHOR11 induced the production of reactive oxygen species (ROS) that trigger autophagy and cellular senescence, but no apoptosis induction. Further analysis showed that JHOR11 presented no tumorigenicity, with no effect in the cellular mobility, as evaluated by thye wound scratch assay, and no anti- or pro-angiogenic effect, as evaluated by the ex-ovo chorioallantoic membrane (CAM) assay. Importantly, JHOR11 presented no toxicity in chicken and zebrafish embryos and reduced in vivo the proliferation of HCT116 injected into zebrafish embryos. These results show that these are suitable complexes for clinical applications with improved tumor cell cytotoxicity and low toxicity, and that counter-anion alteration might be a viable clinical strategy for improving chemotherapy outcomes in multidrug-resistant (MDR) tumors.

Quercetin Liposomal Nanoformulation for Ischemia and Reperfusion Injury Treatment, Ferreira‐silva, Margarida, Faria‐silva Catarina, Carvalheiro {Manuela C. }, Simões Sandra, Marinho Susana} {H., Marcelino Paulo, Campos {Maria Celeste}, Metselaar {Josbert M. }, Fernandes Eduarda, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Corvo Luísa} {M. , Pharmaceutics, jan, Volume 14, Number 1, (2022) Abstract

Ischemia and reperfusion injury (IRI) is a common complication caused by inflammation and oxidative stress resulting from liver surgery. Current therapeutic strategies do not present the desirable efficacy, and severe side effects can occur. To overcome these drawbacks, new therapeutic alternatives are necessary. Drug delivery nanosystems have been explored due to their capacity to improve the therapeutic index of conventional drugs. Within nanocarriers, liposomes are one of the most successful, with several formulations currently in the market. As improved therapeutic outcomes have been demonstrated by using liposomes as drug carriers, this nanosystem was used to deliver quercetin, a flavonoid with anti-inflammatory and antioxidant properties, in hepatic IRI treatment. In the present work, a stable quercetin liposomal formulation was developed and characterized. Additionally, an in vitro model of ischemia and reperfusion was developed with a hypoxia chamber, where the anti-inflammatory potential of liposomal quercetin was evaluated, revealing the downregulation of pro-inflammatory markers. The anti-inflammatory effect of quercetin liposomes was also assessed in vivo in a rat model of hepatic IRI, in which a decrease in inflammation markers and enhanced recovery were observed. These results demonstrate that quercetin liposomes may provide a significant tool for addressing the current bottlenecks in hepatic IRI treatment.

Manganese(I) tricarbonyl complexes as potential anticancer agents, Lenis-Rojas, {Oscar A. }, Carvalho Beatriz, Cabral Rui, Silva Margarida, Friães Sofia, Roma-Rodrigues Catarina, Meireles {Marta S. H. }, Gomes {Clara S. B. }, Fernández {Jhonathan A. A. }, Vila {Sabela F. }, Rubiolo {Juan A. }, Sanchez Laura, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Royo Beatriz , JBIC Journal of Biological Inorganic Chemistry, feb, Volume 27, Number 1, p.49–64, (2022) Abstract

The antiproliferative activity of [Mn(CO)3(N^N)Br] (N^N = phendione 1, bipy 3) and of the two newly synthesized Mn complexes [Mn(CO)3(acridine)(phendione)]OTf (2) and [Mn(CO)3(di-triazole)Br] (4) has been evaluated by MTS against three tumor cell lines A2780 (ovarian carcinoma), HCT116 (colorectal carcinoma), HCT116doxR (colorectal carcinoma resistant to doxorubicin), and in human dermal fibroblasts. The antiproliferative assay showed a dose-dependent effect higher in complex 1 and 2 with a selectivity toward ovarian carcinoma cell line 21 times higher than in human fibroblasts. Exposure of A2780 cells to IC50 concentrations of complex 1 and 2 led to an increase of reactive oxygen species that led to the activation of cell death mechanisms, namely via intrinsic apoptosis for 2 and autophagy and extrinsic apoptosis for 1. Both complexes do not target DNA or interfere with cell cycle progression but are able to potentiate cell migration and neovascularization (for 2) an indicative that their application might be directed for initial tumor stages to avoid tumor invasion and metastization and opening a new avenue for complex 2 application in regenerative medicine. Interestingly, both complexes do not show toxicity in both in vivo models (CAM and zebrafish). Graphical abstract: [Figure not available: see fulltext.]

2021
Vanadium(IV) complexes with methyl-substituted 8-hydroxyquinolines: Catalytic potential in the oxidation of hydrocarbons and alcohols with peroxides and biological activity, Palion-Gazda, Joanna, Luz André, Raposo {Luis R. }, Choroba Katarzyna, Nycz {Jacek E. }, Bieńko Alina, Lewińska Agnieszka, Erfurt Karol, Baptista {Pedro V. }, Machura Barbara, Fernandes {Alexandra R. }, Shul’pina {Lidia S. }, Ikonnikov {Nikolay S. }, and Shul’pin {Georgiy B. } , Molecules, oct, Volume 26, Number 21, (2021) Abstract

Methyl-substituted 8-hydroxyquinolines (Hquin) were successfully used to synthetize five-coordinated oxovanadium(IV) complexes: [VO(2,6-(Me)2-quin)2 ] (1), [VO(2,5-(Me)2-quin)2 ] (2) and [VO(2-Me-quin)2 ] (3). Complexes 1–3 demonstrated high catalytic activity in the oxidation of hydrocarbons with H2 O2 in acetonitrile at 50◦ C, in the presence of 2-pyrazinecarboxylic acid (PCA) as a cocatalyst. The maximum yield of cyclohexane oxidation products attained was 48%, which is high in the case of the oxidation of saturated hydrocarbons. The reaction leads to the formation of a mixture of cyclohexyl hydroperoxide, cyclohexanol and cyclohexanone. When triphenylphosphine is added, cyclohexyl hydroperoxide is completely converted to cyclohexanol. Consideration of the regioand bond-selectivity in the oxidation of n-heptane and methylcyclohexane, respectively, indicates that the oxidation proceeds with the participation of free hydroxyl radicals. The complexes show moderate activity in the oxidation of alcohols. Complexes 1 and 2 reduce the viability of colorectal (HCT116) and ovarian (A2780) carcinoma cell lines and of normal dermal fibroblasts without showing a specific selectivity for cancer cell lines. Complex 3 on the other hand, shows a higher cytotoxicity in a colorectal carcinoma cell line (HCT116), a lower cytotoxicity towards normal dermal fibroblasts and no effect in an ovarian carcinoma cell line (order of magnitude HCT116 > fibroblasts > A2780).

New non-toxic n-alkyl cholinium-based ionic liquids as excipients to improve the solubility of poorly water-soluble drugs, Jesus, {Ana R. }, Raposo {Luís R. }, Soromenho {Mário R. C. }, Agostinho {Daniela A. S. }, Esperan{\c c}a {José M. S. S. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Reis {Patrícia M. } , Symmetry, nov, Volume 13, Number 11, (2021) Abstract

In this work, we prepared new biocompatible N-alkyl cholinium-based ionic liquids to be used as cosolvents to improve the solubility of poorly water-soluble drugs, namely, sodium diclo-fenac and paracetamol. In this set of ionic liquids, we intend to understand the effect of increasing the asymmetry of the ionic liquid cation/anion by growing the length of one of the alkyl chains attached to the nitrogen center/sulfonate center on the dissolution capacity of the ionic liquid. The addition of these new ionic liquids to water increased the dissolution capacity of the drugs up to four-times that in water, and improved the pharmacodynamic properties of these drugs, especially the case of sodium diclofenac. The intermolecular interactions between the drugs and ionic liquids were investigated by NMR. Two-dimensional1H/1H nuclear overhauser effect spectroscopy (NO-ESY) revealed an interaction between sodium diclofenac and the alaninate anion from the [C2Ch]2[SucAla]. In the case of paracetamol and [C4Ch][C2SO3], it was possible to observe two inter-molecular interactions between the hydroxyl group of paracetamol and two protons from the cation [C4Ch]+. Interestingly, the ionic liquid bearing a succinyl-DL-alaninate anion, [SucAla]2−, and a N-ethyl cholinium cation, [C2Ch]+, which presented the highest ability to dissolve sodium diclofenac, showed no cytotoxicity up to 500 mM. Therefore, this ionic liquid is a potential candidate for drug delivery applications.

Copper(ii) complexes with tridentate halogen-substituted Schiff base ligands: synthesis, crystal structures and investigating the effect of halogenation, leaving groups and ligand flexibility on antiproliferative activities, Kordestani, Nazanin, {Amiri Rudbari} Hadi, Fernandes {Alexandra R. }, Raposo {Luís R. }, Luz André, Baptista {Pedro V. }, Bruno Giuseppe, Scopelliti Rosario, Fateminia Zohreh, Micale Nicola, Tumanov Nikolay, Wouters Johan, {Abbasi Kajani} Abolghasem, and Bordbar {Abdol Khalegh} , Dalton Transactions, mar, Volume 50, Number 11, p.3990–4007, (2021) Abstract

To investigate the effect of different halogen substituents and leaving groups and the flexibility of ligands on the anticancer activity of copper complexes, sixteen copper(ii) complexes with eight different tridentate Schiff-base ligands containing pyridine and 3,5-halogen-substituted phenol moieties were synthesized and characterized by spectroscopic methods. Four of these complexes were also characterized by X-ray crystallography. The cytotoxicity of the complexes was determined in three different tumor cell lines (i.e.the A2780 ovarian, HCT116 colorectal and MCF7 breast cancer cell line) and in a normal primary fibroblast cell line. Complexes were demonstrated to induce a higher loss of cell viability in the ovarian carcinoma cell line (A2780) with respect to the other two tumor cell lines, and therefore the biological mechanisms underlying this loss of viability were further investigated. Complexes with ligandL1(containing a 2-pycolylamine-type motif) were more cytotoxic than complexes withL2(containing a 2-(2-pyridyl)ethylamine-type motif). The loss of cell viability in A2780 tumor cells was observed in the orderCu(Cl2-L1)NO3>Cu(Cl2-L1)Cl>Cu(Br2-L1)Cl>Cu(BrCl-L1)Cl. All complexes were able to induce reactive oxygen species (ROS) that could be related to the loss of cell viability. ComplexesCu(BrCl-L1)ClandCu(Cl2-L1)NO3were able to promote A2780 cell apoptosis and autophagy and for complexCu(BrCl-L1)Clthe increase in apoptosis was due to the intrinsic pathway.Cu(Cl2-L1)ClandCu(Br2-L1)Clcomplexes lead to cellular detachment allowing to correlate with the results of loss of cell viability. Despite the ability of theCu(BrCl-L1)Clcomplex to induce programmed cell death in A2780 cells, its therapeutic window turned out to be low making theCu(Cl2-L1)NO3complex the most promising candidate for additional biological applications.

Rosa x hybrida extracts with dual actions: Antiproliferative effects against tumour cells and inhibitor of Alzheimer disease, Rivas-García, Lorenzo, Quiles {José L. }, Roma-Rodrigues Catarina, Raposo {Luis R. }, Navarro-Hortal {María D. }, Romero-Márquez {Jose M. }, Esteban-Muñoz Adelaida, Varela-López Alfonso, García {Laura Carrera}, Cianciosi Danila, {Forbes Hernández} {Tamara Y. }, Battino Maurizio, Llopis Juan, Fernandes {Alexandra R. }, Baptista {Pedro V. }, and Sánchez-González Cristina , Food and Chemical Toxicology, mar, Volume 149, (2021) Abstract

Edible flowers are being used as a new ingredient in modern gastronomy. Recently, these products have also gained interest as an important source of phenolic compounds with potential for biomedical applications. The present work studied a methanolic extract of Rosa x hybrida in which 35 individual phenolic compounds were identified. The extract has been evaluated for its antiproliferative properties in ovarian carcinoma cells. Results showed that the antiproliferative effect was associated with the induction of autophagy and apoptosis with the concomitant ROS increase probably related to mitochondria dysfunction. These antiproliferative effects might be associated with some components of the extract such as quercetin. The extract did not induce damage in healthy cells and that it was able to improve the wound healing activity. The present study also evaluated the properties of the mentioned extract in vivo in C. elegans. Tests demonstrated a lack of toxicity in the worm model. Promising results have been obtained in transgenic strains of C. elegans that produce human beta amyloid peptide, suggesting the possible utility of the extract from the point of view of Alzheimer disease. Altogether, results suggest that Rosa x hybrida extracts could be a new tool for the development of functional foods.

Square planar Au(III), Pt(II) and Cu(II) complexes with quinoline-substituted 2,2′:6′,2″-terpyridine ligands: From in vitro to in vivo biological properties, Choroba, Katarzyna, Machura Barbara, Szlapa-Kula Agata, Malecki {Jan G. }, Raposo Luis, Roma-Rodrigues Catarina, Cordeiro Sandra, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , European Journal of Medicinal Chemistry, jun, Volume 218, (2021) Abstract

Cancer is the second leading cause of death worldwide. Cisplatin has challenged cancer treatment; however, resistance and side effects hamper its use. New agents displaying improved activity and more reduced side effects relative to cisplatin are needed. In this work we present the synthesis, characterization and biological activities of three complexes with quinoline-substituted 2,2′:6′,2″-terpyridine ligand: [Pt(4′-(2-quin)-terpy)Cl](SO3CF3) (1), [Au(4′-(2-quin)-terpy)Cl](PF6)2·CH3CN (2) and [Cu(4′-(2-quin)-terpy)Cl](PF6) (3). The three complexes displayed a high antiproliferative activity in ovarian carcinoma cell line (A2780) and even more noticeable in a colorectal carcinoma cell line (HCT116) following the order 3 > 2 > 1. The complexes IC50 are at least 20 × lower than the IC50 displayed by cisplatin (15.4 μM) in HCT116 cell line while displaying at the same time, much reduced cytotoxicity in a normal dermal fibroblast culture. These cytotoxic activities seem to be correlated with the inclination angles of 2-quin unit to the central pyridine. Interestingly, all complexes can interact with calf-thymus DNA (CT-DNA) in vitro via different mechanisms, although intercalation seems to be the preferred mechanism at least for 2 and 3 at higher concentrations of DNA. Moreover, circular dichroism (CD) data seems to indicate that complex 3, more planar, induces a high destabilization of the DNA double helix (shift from B-form to Z-form). Higher the deviation from planar, the lower the cytotoxicity displayed by the complexes. Cellular uptake may be also responsible for the different cytotoxicity exhibited by complexes with 3 > 2 >1. Complex 2 seems to enter cells more passively while complex 1 and 3 might enter cells via energy-dependent and -independent mechanisms. Complexes 1–3 were shown to induce ROS are associated with the increased apoptosis and autophagy. Moreover, all complexes dissipate the mitochondrial membrane potential leading to an increased BAX/BCL-2 ratio that triggered apoptosis. Complexes 2 and 3 were also shown to exhibit an anti-angiogenic effect by significantly reduce the number of newly formed blood vessel in a CAM model with no toxicity in this in vivo model. Our results seem to suggest that the increased cytotoxicity of complex 3 in HCT116 cells and its potential interest for further translation to pre-clinical mice xenografts might be associated with: 1) higher % of internalization of HCT116 cells via energy-dependent and -independent mechanisms; 2) ability to intercalate DNA and due to its planarity induced higher destabilization of DNA; 3) induce intracellular ROS that trigger apoptosis and autophagy; 4) low toxicity in an in vivo model of CAM; 5) potential anti-angiogenic effect.

Exploiting the antiproliferative potential of spiropyrazoline oxindoles in a human ovarian cancer cell line, Raposo, {Luís R. }, Silva {Ana Rute}, Silva Dário, Roma-Rodrigues Catarina, Espadinha Margarida, Baptista {Pedro V. }, Santos {Maria M. M. }, and Fernandes {Alexandra R. } , Bioorganic and Medicinal Chemistry, jan, Volume 30, (2021) Abstract

Cancer is still one of the deadliest diseases worldwide despite the efforts in its early detection and treatment strategies. However, most chemotherapeutic agents still present side effects in normal tissues and acquired resistance that limit their efficacy. Spiropyrazoline oxindoles might be good alternatives as they have shown antiproliferative activity in human breast and colon cancer cell lines, without eliciting cytotoxicity in healthy cells. However, their potential for ovarian cancer was never tested. In this work, the antiproliferative activity of five spiropyrazoline oxindoles was assessed in ovarian cancer cells A2780 and the biological targets and mechanism of action of the most promising compound evaluated. Compound 1a showed the highest antiproliferative effect, as well as the highest selectivity for A2780 cells compared to healthy fibroblasts. This antiproliferative effect results from the induction of cell death by mitochondria-mediated apoptosis and autophagy. In vitro DNA interaction studies demonstrated that 1a interacts with DNA by groove-binding, without triggering genotoxicity. In addition, 1a showed a strong affinity to bovine serum albumin that might be important for further inclusion in drug delivery platforms. Proteomic studies reinforced 1a role in promoting A2780 endoplasmatic reticulum (ER) stress by destabilizing the correct protein folding which triggers cell death via apoptosis and autophagy.

Cu(i) complexes as new antiproliferative agents against sensitive and doxorubicin resistant colorectal cancer cells: synthesis, characterization, and mechanisms of action, Sequeira, Diogo, Baptista {Pedro V. }, Valente Ruben, Piedade Fátima {M. M. M. }, Garcia Helena} {M., Morais {Tânia S. }, and Fernandes {Alexandra R. } , Dalton Transactions, feb, Volume 50, Number 5, p.1845–1865, (2021) Abstract

Cancer is one of the worst health issues worldwide, representing the second leading cause of death. Current chemotherapeutic drugs face some challenges like the acquired resistance of the tumoral cells and low specificity leading to unwanted side effects. There is an urgent need to develop new compounds that may target resistant cells. The synthesis and characterization of two Cu(i) complexes of general formula [Cu(PP)(LL)][BF4], where PP is a phosphane ligand (triphenylphosphine or 1,2-bis(diphenylphosphano) ethane) and LL = is a heteroaromatic bidentate ligand (4,4′-dimethyl-2,2′-bipyridine and 6,3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine). The new compounds were fully characterized by spectroscopic techniques (NMR, FTIR and UV-vis.), elemental analysis (C, H, N and S) and two structures were determined by single X-ray diffraction studies. The antiproliferative potential of the new Cu(i) complexes were studied in tumor (breast adenocarcinoma, ovarian carcinoma and in colorectal carcinoma sensitive and resistant to doxorubicin) and normal (fibroblasts) cell lines. Complexes1-4did not show any antiproliferative potential. Amongst the complexes5-8, complex8shows high cytotoxic potential against colorectal cancer sensitive and resistant to doxorubicin and low cytotoxicity towards healthy cells. We show that complexes5-8can cleave pDNA and, in particular, thein vitropDNA cleavage is due to an oxidative mechanism. This oxidative mechanism corroborates the induction of reactive oxygen species (ROS), that triggers HCT116 cell deathviaapoptosis, as proved by the increased expression of BAX protein relative to BCL-2 protein and the depolarization of mitochondrial membrane potential, andviaautophagy. Additionally, complex8can block the cell cycle in the G1 phase, also exhibiting a cytostatic potential. Proteomic analysis confirmed the apoptotic, autophagic and cytostatic potential of complex8, as well as its ability to produce ROS and cause DNA damage. The interference of the complex in folding and protein synthesis and its ability to cause post-translational modifications was also verified. Finally, it was observed that the complex causes a reduction in cellular metabolism. The results herein demonstrated the potential of Cu(i) complexes in targeting doxorubicin sensitive and resistant cells which is positive and must be further explored usingin vivoanimal models.

Genetic predisposition for aggressive behaviour related with dopamine and serotonin pathways - an overview, Paulino, Cathy, Fernandes {Alexandra R. }, Baptista {Pedro V. }, Soeiro Cristina, Grosso {Ana Rita}, and Quintas Alexandre , Annals of Medicine, apr, Volume 53, Number SI, p.S77–S77, (2021) Abstract
n/a
2020
The intracellular number of magnetic nanoparticles modulates the apoptotic death pathway after magnetic hyperthermia treatment, Beola, Lilianne, Asín Laura, Roma-Rodrigues Catarina, Fernandez-Afonso Yilian, Fratila {Raluca M. }, Serantes David, Ruta Sergiu, Chantrell {Roy W. }, Fernandes {Alexandra R. }, Baptista {Pedro V. }, {de la Fuente} {Jesus M. }, Grazu Valeria, and Gutierrez Lucía , ACS Applied Materials & Interfaces, sep, Volume 12, Number 39, p.43474–43487, (2020) Abstract

Magnetic hyperthermia is a cancer treatment based on the exposure of magnetic nanoparticles to an alternating magnetic field in order to generate local heat. In this work, 3D cell culture models were prepared to observe the effect that a different number of internalized particles had on the mechanisms of cell death triggered upon the magnetic hyperthermia treatment. Macrophages were selected by their high capacity to uptake nanoparticles. Intracellular nanoparticle concentrations up to 7.5 pg Fe/cell were measured both by elemental analysis and magnetic characterization techniques. Cell viability after the magnetic hyperthermia treatment was decreased to <25% for intracellular iron contents above 1 pg per cell. Theoretical calculations of the intracellular thermal effects that occurred during the alternating magnetic field application indicated a very low increase in the global cell temperature. Different apoptotic routes were triggered depending on the number of internalized particles. At low intracellular magnetic nanoparticle amounts (below 1 pg Fe/cell), the intrinsic route was the main mechanism to induce apoptosis, as observed by the high Bax/Bcl-2 mRNA ratio and low caspase-8 activity. In contrast, at higher concentrations of internalized magnetic nanoparticles (1−7.5 pg Fe/cell), the extrinsic route was observed through the increased activity of caspase-8. Nevertheless, both mechanisms may coexist at intermediate iron concentrations. Knowledge on the different mechanisms of cell death triggered after the magnetic hyperthermia treatment is fundamental to understand the biological events activated by this procedure and their role in its effectiveness.

Water safety screening via multiplex LAMP-Au-nanoprobe integrated approach, Oliveira, {Beatriz B. }, Veigas Bruno, Carlos {Fábio Ferreira}, Sánchez-Melsió Alexandre, Balcázar {José Luís}, Borrego {Carles M. }, and Baptista {Pedro Viana} , Science of the Total Environment, nov, Volume 741, (2020) Abstract

Contaminated water resources remain a major global concern regarding public health. The majority of water safety protocols include indicators of microbial contamination to evaluate the potential risk to public health and are key elements of quality guidelines. Among these, markers for total coliforms and fecal coliforms are strong indicators of co-contamination with other pathogens. Traditional methods, recurring to slow and cumbersome culture-based approaches, have been gradually replaced by molecular methods, capable of faster and more specific screening. These are usually PCR-based methods that may allow for multiple pathogen detection but require dedicated laboratory equipment, hindering the rapid on-site assessment. Here, we used a multiplex Loop-Mediated Isothermal Amplification (mLAMP) strategy for the amplification of two markers associated with the contamination by total and fecal coliforms (e.g. Escherichia coli) — lacZ and uidA genes, respectively — thus allowing for single tube multiplex detection. The mLAMP products were then subject to an Au-nanoprobe colorimetric detection assay for precise discrimination of targets. This approach was validated in 22 water samples that were also screened for the presence of lacZ and uidA using standard and quantitative PCR, with the capability for discriminating the contamination level, e.g. a semi-quantitative evaluation of water quality.

Antiproliferative Activities of Diimine-Based Mixed Ligand Copper(II) Complexes, Kordestani, Nazanin, Rudbari {Hadi Amiri}, Fernandes {Alexandra R. }, Raposo {Luís R. }, Baptista {Pedro V. }, Ferreira {Daniela A. }, Bruno Giuseppe, Bella Giovanni, Scopelliti Rosario, Braun {Jason D. }, Herbert {David E. }, and Blacque Olivier , ACS Combinatorial Science, feb, Volume 22, Number 2, p.89–99, (2020) Abstract

A series of Cu(diimine)(X-sal)(NO3) complexes, where the diimine is either 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen) and X-sal is a monoanionic halogenated salicylaldehyde (X = Cl, Br, I, or H), have been synthesized and characterized by elemental analysis and X-ray crystallography. Penta-coordinate geometries copper(II) were observed for all cases. The influence of the diimine coligands and different halogen atoms on the antiproliferative activities toward human cancer cell lines have been investigated. All Cu(II) complexes were able to induce a loss of A2780 ovarian carcinoma cell viability, with phen derivatives more active than bpy derivatives. In contrast, no in vitro antiproliferative effects were observed against the HCT116 colorectal cancer cell line. These cytotoxicity differences were not due to a different intracellular concentration of the complexes determined by inductively coupled plasma atomic emission spectroscopy. A small effect of different halogen substituents on the phenolic ring was observed, with X = Cl being the most highly active toward A2780 cells among the phen derivatives, while X = Br presented the lowest IC50 in A2780 cells for bpy analogs. Importantly, no reduction in normal primary fibroblasts cell viability was observed in the presence of bpy derivatives (IC50 > 40 μM). Mechanistically, complex 1 seems to induce a stronger apoptotic response with a higher increase in mitochondrial membrane depolarization and an increased level of intracellular reactive oxygen species (ROS) compared to complex 3. Together, these data and the low IC50 compared to cisplatin in A2780 ovarian carcinoma cell line demonstrate the potential of these bpy derivatives for further in vivo studies.

Improving the Anti-inflammatory Response via Gold Nanoparticle Vectorization of CO-Releasing Molecules, Fernandes, {Alexandra R. }, c}a-Martins Inês Mendon{\c, Santos {Marino F. A. }, Raposo {Luís R. }, Mendes Rita, Marques Joana, Romão {Carlos C. }, Romão {Maria João}, Santos-Silva Teresa, and Baptista {Pedro V. } , ACS Biomaterials Science and Engineering, feb, Volume 6, Number 2, p.1090–1101, (2020) Abstract

CO-releasing molecules (CORMs) have been widely studied for their anti-inflammatory, antiapoptotic, and antiproliferative effects. CORM-3 is a water-soluble Ru-based metal carbonyl complex, which metallates serum proteins and readily releases CO in biological media. In this work, we evaluated the anti-inflammatory and wound-healing effects of gold nanoparticles-CORM-3 conjugates, AuNPs@PEG@BSA·Ru(CO)x, exploring its use as an efficient CO carrier. Our results suggest that the nanoformulation was capable of inducing a more pronounced cell effect, at the anti-inflammatory level and a faster tissue repair, probably derived from a rapid cell uptake of the nanoformulation that results in the increase of CO inside the cell.

Size-Dependent Biological Activities of Fluorescent Organosilane-Modified Zinc Oxide Nanoparticles, s}il{\u a}, Mariana Bu{\c, a}b{\u a}caru Aurel T. {\u, s}sat Viorica Mu{\c, Vasile {Bogdan S}tefan} {\c, Nea{\c s}u {Ionela Andreea}, Pinheiro Teresa, Roma-Rodrigues Catarina, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Matos {António Pedro}, and Marques {Fernanda Marujo} , Journal of biomedical nanotechnology, feb, Volume 16, Number 2, p.137–152, (2020) Abstract

Surface modification of zinc oxide nanoparticles (ZnO NPs) is a strategy to tune their biocompatibility. Herein we report on the synthesis of a series of fluorescent ZnO NPs modified with 2-10% (3-glycidyloxypropyl)trimethoxysilane (GPTMS) to investigate the fluorescence properties and to explore their applications in microbiology and biomedicine. The obtained ZnO NPs were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FTIR). Size reduction occurred from ca. 13 nm in unmodified ZnO to 3-4 nm in silane-modified samples and fluorescence spectra showed size-dependent variation of the photoemission bands' intensity. The antibacterial and cytotoxic activities were investigated on Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria, and in ovarian (A2780) and prostate (PC3) cancer cells by tetrazolium/formazan-based methods. The antibacterial effect was higher for E. coli than S. aureus, while the cytotoxic activity was similar for both cancer cells and varied with the particle size. Cell death by apoptosis, and/or necrosis versus autophagy, were explored by flow cytometry using an Annexin V based-method and transmission electron microscopy (TEM). The main mechanism of ZnO NPs toxicity may involve the generation of reactive oxygen species (ROS) and the induction of apoptosis or autophagy. This work revealed the potential utility of GPTMS-modified ZnO NPs in the treatment of bacterial infection and cancer.

RNA Quantification Using Noble Metal Nanoprobes: Simultaneous Identification of Several Different mRNA Targets Using Color Multiplexing and Application to Chronic Myeloid Leukemia Diagnostics, Baptista, {Pedro Viana} , Nanoparticles in Biology and Medicine, United States, p.251–268, (2020) Abstract

Nanotechnology provides new tools for gene expression analysis that allow for sensitive and specific characterization of prognostic signatures related to cancer. Cancer is a complex disease where multiple gene loci contribute to the phenotype. The ability to simultaneously monitor differential expression originating from each locus allows for a more accurate indication into the degree of cancerous activity than either locus alone. Metal nanoparticles have been widely used as labels for in vitro identification and quantification of target sequences. Here we describe the synthesis of nanoparticles with different noble metal compositions in an alloy format that are then functionalized with thiol-modified ssDNA (nanoprobes). We also show how such nanoprobes are used in a non-cross-linking colorimetric method for the direct detection and quantification of specific mRNA targets, without the need for enzymatic amplification or reverse-transcription steps. The different metals in the alloy provide for distinct absorption spectra due to their characteristic plasmon resonance peaks. The color multiplexing allows for simultaneous identification of different mRNA targets involved in cancer development. A comparison of the absorption spectra of the nanoprobe mixtures taken before and after induced aggregation of metal nanoparticles allows to both identify and quantify each mRNA target. We describe the use of gold and gold–silver alloy nanoprobes for the development of the non-cross-linking method to detect a specific BCR-ABL fusion gene (e.g., e1a2 and e14a2) mRNA target associated with chronic myeloid leukemia (CML) using 10 ng/μL of unamplified total human RNA. Additionally, we demonstrate the use of this approach for the direct diagnostics of CML. This simple methodology takes less than 50 min to complete after total RNA extraction with comparable specificity and sensitivity to the more commonly used methods.

2019
Antiproliferative activity of heterometallic sodium and potassium-dioxidovanadium(V) polymers, Sutradhar, Manas, Alegria {Elisabete C. B. A. }, Ferretti Francesco, Raposo {Luís R. }, {Guedes da Silva} Fátima {M. C. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Pombeiro {Armando J. L. } , Journal of Inorganic Biochemistry, nov, Volume 200, (2019) Abstract

The syntheses of the heterometallic sodium and potassium-dioxidovanadium 2D polymers, [NaVO2(1κNOO’;2κO”-L)(H2O)]n (1) and [KVO2(1κNOO’;2κO’;3κO”-L)(EtOH)]n (2) (where the κ notation indicates the coordinating atoms of the polydentate ligand L) derived from (3,5-di-tert-butyl-2-hydroxybenzylidene)-2-hydroxybenzohydrazide (H2L) are reported. The polymers were characterized by IR, NMR, elemental analysis and single crystal X-ray diffraction analysis. The antiproliferative potential of 1 and 2 was examined towards four human cancer cell lines (ovarian carcinoma, A2780, colorectal carcinoma, HCT116, prostate carcinoma, PC3 and breast adenocarcinoma, MCF-7cell lines) and normal human fibroblasts. Complex 1 and 2 showed the highest cytotoxic activity against A2780 cell line (IC50 8.2 and 11.3 μM, respectively) with 1 > 2 and an IC50 in the same range as cisplatin (IC50 3.4 μM; obtained in the same experimental conditions) but, interestingly, with no cytotoxicity to healthy human fibroblasts for concentrations up to 75 μM. This high cytotoxicity of 1 in ovarian cancer cells and its low cytotoxicity in healthy cells demonstrates its potential for further biological studies. Our results suggest that both complexes induce ovarian carcinoma cell death via apoptosis and autophagy, but autophagy is the main biological cause of the reduction of viability observed and that ROS (reactive oxygen species) may play an important role in triggering cell death.

Ionic Liquids and Salts from Ibuprofen as Promising Innovative Formulations of an Old Drug, Santos, {Miguel M. }, Raposo {Luís R. }, c}alo Carrera {Gon{\c V. S. M. }, Costa Alexandra, Dionísio Madalena, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Branco {Luís C. } , Chemmedchem, may, Volume 14, Number 9, (2019) Abstract

Herein we report the synthesis of novel ionic liquids (ILs) and organic salts by combining ibuprofen as anion with ammonium, imidazolium, or pyridinium cations. The methodology consists of an acid–base reaction of neutral ibuprofen with cation hydroxides, which were previously prepared by anion exchange from the corresponding halide salts with Amberlyst A-26(OH). In comparison with the parent drug, these organic salts display higher solubility in water and biological fluids and a smaller degree of polymorphism, which in some cases was completely eliminated. With the exception of [C 16 Pyr][Ibu] and [N 1,1,2,2OH1 ][Ibu], the prepared salts did not affect the viability of normal human dermal fibroblasts or ovarian carcinoma (A2780) cells. Therefore, these ibuprofen-based ionic liquids may be very promising lead candidates for the development of effective formulations of this drug.