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Pedrosa, P, Mendes R, Cabral R, Martins LMDRS, Baptista PV, Fernandes AR.  2018.  Combination of chemotherapy and Au-nanoparticle photothermy in the visible light to tackle doxorubicin resistance in cancer cells, 2018. Scientific Reports. 8(1):11429. AbstractWebsite

Despite great advances in the fight against cancer, traditional chemotherapy has been hindered by the dose dependent adverse side effects that reduce the usable doses for effective therapy. This has been associated to drug resistance in tumor cells that often cause relapse and therapy failure. These drawbacks have been tackled by combining different therapeutic regiments that prevent drug resistance while decreasing the chemotherapy dose required for efficacious ablation of cancer. In fact, new metallic compounds have been in a continuous development to extend the existing chemotherapy arsenal for these combined regimens. Here, we demonstrate that combination of a metallic compound (TS265), previously characterized by our group, with photothermy circumvents cells resistant to Doxorubicin (DOX). We first engendered a colorectal carcinoma cell line (HCT116) highly resistant to DOX, whose viability was diminished after administration of TS265. Cancer cell death was potentiated by challenging these cells with 14 nm spherical gold nanoparticles followed by laser irradiation at 532 nm. The combination of TS265 with photothermy lead to 65% cell death of the DOX resistant cells without impacting healthy cells. These results support the use of combined chemotherapy and photothermy in the visible spectrum as an efficient tool for drug resistant tumors.

Gomes, SE, Pereira DM, Roma-Rodrigues C, Fernandes AR, Borralho PM, Rodrigues CMP.  2018.  Convergence of miR-143 overexpression, oxidative stress and cell death in HCT116 human colon cancer cells, 2018. PLoS One. 13(1):e0191607. AbstractWebsite

MicroRNAs (miRNAs) regulate a wide variety of biological processes, including tumourigenesis. Altered miRNA expression is associated with deregulation of signalling pathways, which in turn cause abnormal cell growth and de-differentiation, contributing to cancer. miR-143 and miR-145 are anti-tumourigenic and influence the sensitivity of tumour cells to chemotherapy and targeted therapy. Comparative proteomic analysis was performed in HCT116 human colon cancer cells stably transduced with miR-143 or miR-145. Immunoblotting analysis validated the proteomic data in stable and transient miRNA overexpression conditions in human colon cancer cells. We show that approximately 100 proteins are differentially expressed in HCT116 human colon cancer cells stably transduced with miR-143 or miR-145 compared to Empty control cells. Further, Gene Ontology and pathway enrichment analysis indicated that proteins involved in specific cell signalling pathways such as cell death, response to oxidative stress, and protein folding might be modulated by these miRNAs. In particular, antioxidant enzyme superoxide dismutase 1 (SOD1) was downregulated by stable expression of either miR-143 or miR-145. Further, SOD1 gain-of-function experiments rescued cells from miR-143-induced oxidative stress. Moreover, miR-143 overexpression increased oxaliplatin-induced apoptosis associated with reactive oxygen species generation, which was abrogated by genetic and pharmacological inhibition of oxidative stress. Overall, miR-143 might circumvent resistance of colon cancer cells to oxaliplatin via increased oxidative stress in HCT116 human colon cancer cells.

Czerwinska, K, Machura B, Kula S, Krompiec S, Erfurt K, Roma-Rodrigues C, Fernandes AR, Shul'pina LS, Ikonnikov NS, Shul'pin GB.  2017.  Copper(ii) complexes of functionalized 2,2[prime or minute]:6[prime or minute],2[prime or minute][prime or minute]-terpyridines and 2,6-di(thiazol-2-yl)pyridine: structure, spectroscopy, cytotoxicity and catalytic activity, 2017. Dalton Transactions. 46(29):9591-9604.: The Royal Society of Chemistry AbstractWebsite

Six new copper(ii) complexes with 2,2[prime or minute]:6[prime or minute],2[prime or minute][prime or minute]-terpyridine (4[prime or minute]-Rn-terpy) [1 (R1 = furan-2-yl), 2 (R2 = thiophen-2-yl), and 3 (R3 = 1-methyl-1H-pyrrol-2-yl)] and 2,6-di(thiazol-2-yl)pyridine derivatives (Rn-dtpy) [4 (R1), 5 (R2), and 6 (R3)] have been synthesized by a reaction between copper(ii) chloride and the corresponding ligand. The complexes have been characterized by UV-vis and IR spectroscopy, and their structures have been determined by X-ray analysis. The antiproliferative potential of copper(ii) complexes of 2,2[prime or minute]:6[prime or minute],2[prime or minute][prime or minute]-terpyridine and 2,6-di(thiazol-2-yl)pyridine derivatives towards human colorectal (HCT116) and ovarian (A2780) carcinoma as well as towards lung (A549) and breast adenocarcinoma (MCF7) cell lines was examined. Complex 1 and complex 6 were found to have the highest antiproliferative effect on A2780 ovarian carcinoma cells, particularly when compared with complex 2, 3 with no antiproliferative effect. The order of cytotoxicity in this cell line is 6 > 1 > 5 > 4 > 2 [approximate] 3. Complex 2 seems to be much more specific towards colorectal carcinoma HCT116 and lung adenocarcinoma A549 cells. The viability loss induced by the complexes agrees with Hoechst 33258 staining and typical morphological apoptotic characteristics like chromatin condensation and nuclear fragmentation. The specificity towards different types of cell lines and the low cytotoxic activity towards healthy cells are of particular interest and are a positive feature for further developments. Complexes 1-6 were also tested in the oxidation of alkanes and alcohols with hydrogen peroxide and tert-butyl-hydroperoxide (TBHP). The most active catalyst 4 gave, after 120 min, 0.105 M of cyclohexanol + cyclohexanone after reduction with PPh3. This concentration corresponds to a yield of 23% and TON = 210. Oxidation of cis-1,2-dimethylcyclohexane with m-CPBA catalyzed by 4 in the presence of HNO3 gave a product of a stereoselective reaction (trans/cis = 0.47). Oxidation of secondary alcohols afforded the target ketones in yields up to 98% and TON = 630.

Choroba, K, Machura B, Kula S, Raposo LR, Fernandes AR, Kruszynski R, Erfurt K, Shul'pina LS, Kozlov YN, Shul'pin GB.  2019.  Copper(ii) complexes with 2,2':6',2''-terpyridine, 2,6-di(thiazol-2-yl)pyridine and 2,6-di(pyrazin-2-yl)pyridine substituted with quinolines. Synthesis, structure, antiproliferative activity, and catalytic activity in the oxidation of alkanes and alcohols, 2019. Dalton Trans. 48(33):12656-12673. AbstractWebsite

A series of 2,2':6',2''-terpyridine (terpy), 2,6-di(thiazol-2-yl)pyridine (dtpy) and 2,6-di(pyrazin-2-yl)pyridine (dppy) derivatives with n-quinolyl substituents (n = 2 and 4) was used to synthesize five-coordinate complexes [CuCl2(n-quinolyl-terpy)] (1-2), [CuCl2(n-quinolyl-dtpy)] (3-4) and [CuCl2(n-quinolyl-dppy)] (5-6), respectively. The main emphasis of the research was to investigate the impact of the triimine skeleton (terpy, dtpy and dppy) and n-quinolyl pendant substituent on the antiproliferative and catalytic properties of 1-6. The obtained Cu(ii) compounds were studied as antiproliferative agents against human colorectal (HCT116) and ovarian (A2780) carcinoma, and they were used as catalysts for the oxidation of alkanes and alcohols with peroxides under mild conditions. The kinetic characteristics of the oxidizing species generated by the catalytic system Cu(ii) complex-H2O2 in CH3CN were obtained from the dependence of the alkane oxidation rate on its initial concentration. A model of competitive interaction of hydroxyl radicals with CH3CN and RH in the catalyst cavity has been proposed which is based on the simultaneous study of kinetics and selectivity in alkane oxidations.

Roma-Rodrigues, C, Fernandes AR, Baptista PV.  2019.  Counteracting the effect of leukemia exosomes by antiangiogenic gold nanoparticles, 2019. Int J Nanomedicine. 14:6843-6854. AbstractWebsite

Purpose: Progression of chronic myeloid leukemia (CML) is frequently associated with increased angiogenesis at the bone marrow mediated by exosomes. The capability of gold nanoparticles (AuNPs) functionalized with antiangiogenic peptides to hinder the formation of new blood vessels has been demonstrated in a chorioallantoic membrane (CAM) model. Methods: Exosomes of K562 CML cell line were isolated and their angiogenic effect assessed in a CAM model. AuNPs functionalized with antiangiogenic peptides were used to block the angiogenic effect of CML-derived exosomes, assessed by evaluation of expression levels of key modulators involved in angiogenic pathways - VEGFA, VEGFR1 (also known as FLT1) and IL8. Results: Exosomes isolated from K562 cells promoted the doubling of newly formed vessels associated with the increase of VEGFR1 expression. This is a concentration and time-dependent effect. The AuNPs functionalized with antiangiogenic peptides were capable to block the angiogenic effect by modulating VEGFR1 associated pathway. Conclusion: Exosomes derived from blast cells are capable to trigger (neo)-angiogenesis, a key factor for the progression and spreading of cancer, in particular in CML. AuNPs functionalized with specific antiangiogenic peptides are capable to block the effect of the exosomes produced by malignant cells via modulation of the intrinsic VEGFR pathway. Together, these data highlight the potential of nanomedicine-based strategies against cancer proliferation.

I.C.J.Palma, S, Carvalho A, Silva J, Fernandes AR, del Puerto-Morales M, Roque ACA.  2015.  Covalent coupling of gum arabic onto superparamagnetic iron oxide nanoparticles for MRI cell labeling: physiochemical and in vitro characterization. Contrast Media and Molecular Imaging. AbstractWebsite

Gum arabic (GA) is a hydrophilic composite polysaccharide derived from exudates of Acacia senegal and Acacia seyal trees. It is biocompatible, possesses emulsifying and stabilizing properties and has been explored as coating agent of nanomaterials for biomedical applications, namely magnetic nanoparticles (MNPs). Previous studies focused on the adsorption of GA onto MNPs produced by co-precipitation methods. In this work, MNPs produced by a thermal decomposition method, known to produce uniform particles with better crystalline properties, were used for the covalent coupling of GA through its free amine groups, which increases the stability of the coating layer. The MNPs were produced by thermal decomposition of Fe(acac)3 in organic solvent and, after ligand-exchange with meso-2,3-dimercaptosuccinic acid (DMSA), GA coating was achieved by the establishment of a covalent bond between DMSA and GA moieties. Clusters of several magnetic cores entrapped in a shell of GA were obtained, with good colloidal stability and promising magnetic relaxation properties (r2 /r1 ratio of 350). HCT116 colorectal carcinoma cell line was used for in vitro cytotoxicity evaluation and cell-labeling efficiency studies. We show that, upon administration at the respective IC50 , GA coating enhances MNP cellular uptake by 19 times compared to particles bearing only DMSA moieties. Accordingly, in vitro MR images of cells incubated with increasing concentrations of GA-coated MNP present dose-dependent contrast enhancement. The obtained results suggest that the GA magnetic nanosystem could be used as a MRI contrast agent for cell-labeling applications.

Vinhas, R, Cordeiro M, Pedrosa P, Fernandes AR, Baptista PV.  2016.  Current trends in molecular diagnostics of chronic myeloid leukemia. Leukemia & Lymphoma. :1-14. AbstractWebsite

Nearly 1.5 million people worldwide suffer from chronic myeloid leukemia (CML), characterized by the genetic translocation t(9;22)(q34;q11.2), involving the fusion of the Abelson oncogene (ABL1) with the breakpoint cluster region (BCR) gene. Early onset diagnosis coupled to current therapeutics allow for a treatment success rate of 90, which has focused research on the development of novel diagnostics approaches. In this review, we present a critical perspective on current strategies for CML diagnostics, comparing to gold standard methodologies and with an eye on the future trends on nanotheranostics.

Gromicho, M, Dinis J, Magalhaes M, Fernandes AR, Tavares P, Laires A, Rueff J, Rodrigues AS.  2011.  Development of imatinib and dasatinib resistance: dynamics of expression of drug transporters ABCB1, ABCC1, ABCG2, MVP, and SLC22A1. Leuk Lymphoma. 52(10):1980-90.11gromicholl.pdf
Tavares, M, Cabral RP, Costa C, Martins P, Fernandes AR, Casimiro T, Aguiar-Ricardo A.  2017.  Development of PLGA dry powder microparticles by supercritical CO2-assisted spray-drying for potential vaccine delivery to the lungs, 2017. 128:235-243. AbstractWebsite

In this work, biocompatible and biodegradable poly(d-l-lactide-co-glycolide) (PLGA) composite microparticles with potential use as carrier for vaccines and other drugs to the lungs were developed using supercritical CO2-assisted spray-drying (SASD). Bovine serum albumin (BSA) was chosen as model vaccine, and l-leucine as a dispersibility enhancer, and their effects on the particle characteristics were evaluated. The dry powder formulations (DPFs) were characterized in terms of their morphology and aerodynamic performance using an in vitro aerosolization study – Andersen cascade impactor (ACI) − to obtain data such as the fine particle fraction (FPF) with percentages up to 43.4%, and the mass median aerodynamic diameter (MMAD) values between the 1.7 and 3.5μm. Additionally, pharmacokinetic and cytotoxicity studies were performed confirming that the produced particles have all the necessary requirements for potential pulmonary delivery.

Mahmudov, KT, da Silva MFCG, Kopylovich MN, Fernandes AR, Silva A, Mizar A, Pombeiro AJL.  2014.  Di- and tri-organotin(IV) complexes of arylhydrazones of methylene active compounds and their antiproliferative activity. J Organomet Chem. 760:67-73.14mahmudovjoc.pdf
Lenis-Rojas, OA, Roma-Rodrigues C, Fernandes AR, Marques F, Pérez-Fernández D, Guerra-Varela J, Sánchez L, Vázquez-García D, López-Torres M, Fernández A, Fernández JJ.  2017.  Dinuclear RuII(bipy)2 Derivatives: Structural, Biological, and in Vivo Zebrafish Toxicity Evaluation, 2017. Inorganic ChemistryInorganic Chemistry. 56(12):7127-7144.: American Chemical Society AbstractWebsite

Ruthenium-based drugs exhibit interesting properties as potential anticancer pharmaceuticals. We herein present the synthesis and characterization of a new family of ruthenium complexes with formulas [{Ru(bipy)2}2(μ-L)][CF3SO3]4 (L = bptz, 1a) and [{Ru(bipy)2}2(μ-L)][CF3SO3]2 (L = arphos, 2a; dppb, 3a; dppf, 4a), which were synthesized from the Ru(II) precursor compound cis-Ru(bipy)2Cl2. The complexes were characterized by elemental analysis, mass spectrometry, 1H and 31P{1H} NMR, IR spectroscopy, and conductivity measurements. The molecular structures for three Ru(II) compounds were determined by single-crystal X-ray diffraction. The newly developed compounds interact with CT-DNA by intercalation, in particular, 2a, 3a, and 4a, which also seemed to induce some extent of DNA degradation. This effect seemed to be related with the formation of reactive oxygen species. The cytotoxic activity was evaluated against A2780, MCF7, and MDAMB231 human tumor cells. Compounds 2a and 4a were the most cytotoxic with activity compared to cisplatin (∼2 μM, 72 h) in the A2780 cisplatin sensitive cells. All the compounds induced A2780 cell death by apoptosis, however, to a lesser extent for compounds 4a and 2a. For these compounds, the mechanism of cell death in addition to apoptosis seemed to involve autophagy. In vivo toxicity was evaluated using the zebrafish embryo model. LC50 estimates varied from 5.397 (3a) to 39.404 (1a) mg/L. Considering the in vivo toxicity in zebrafish embryos and the in vitro cytotoxicity in cancer cells, compound 1a seems to be the safest having no effect on dechirionation and presenting a good antiproliferative activity against ovarian carcinoma cells.Ruthenium-based drugs exhibit interesting properties as potential anticancer pharmaceuticals. We herein present the synthesis and characterization of a new family of ruthenium complexes with formulas [{Ru(bipy)2}2(μ-L)][CF3SO3]4 (L = bptz, 1a) and [{Ru(bipy)2}2(μ-L)][CF3SO3]2 (L = arphos, 2a; dppb, 3a; dppf, 4a), which were synthesized from the Ru(II) precursor compound cis-Ru(bipy)2Cl2. The complexes were characterized by elemental analysis, mass spectrometry, 1H and 31P{1H} NMR, IR spectroscopy, and conductivity measurements. The molecular structures for three Ru(II) compounds were determined by single-crystal X-ray diffraction. The newly developed compounds interact with CT-DNA by intercalation, in particular, 2a, 3a, and 4a, which also seemed to induce some extent of DNA degradation. This effect seemed to be related with the formation of reactive oxygen species. The cytotoxic activity was evaluated against A2780, MCF7, and MDAMB231 human tumor cells. Compounds 2a and 4a were the most cytotoxic with activity compared to cisplatin (∼2 μM, 72 h) in the A2780 cisplatin sensitive cells. All the compounds induced A2780 cell death by apoptosis, however, to a lesser extent for compounds 4a and 2a. For these compounds, the mechanism of cell death in addition to apoptosis seemed to involve autophagy. In vivo toxicity was evaluated using the zebrafish embryo model. LC50 estimates varied from 5.397 (3a) to 39.404 (1a) mg/L. Considering the in vivo toxicity in zebrafish embryos and the in vitro cytotoxicity in cancer cells, compound 1a seems to be the safest having no effect on dechirionation and presenting a good antiproliferative activity against ovarian carcinoma cells.

Vinhas, R, Lourenco A, Santos S, Ribeiro P, Silva M, de Sousa AB, Baptista PV, Fernandes AR.  2018.  A double Philadelphia chromosome-positive chronic myeloid leukemia patient, co-expressing P210(BCR-ABL1) and P195(BCR-ABL1) isoforms, 2018. Haematologica. 103(11):e549-e552. AbstractWebsite
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Jesus, AR, Soromenho MRC, Raposo LR, Esperanca J, Baptista PV, Fernandes AR, Reis PM.  2019.  Enhancement of water solubility of poorly water-soluble drugs by new biocompatible N-acetyl amino acid N-alkyl cholinium-based ionic liquids, 2019. Eur J Pharm Biopharm. 137:227-232. AbstractWebsite

The major challenge of the pharmaceutical industry is to find potential solvents for poorly water-soluble drug molecules. Ionic liquids (ILs) have attracted this industry as (co-) solvents due to their unique physicochemical and biological properties. Herein, a straightforward approach for the enhancement of the water solubility of paracetamol and sodium diclofenac is presented, using new biocompatible N-acetyl amino acid N-alkyl cholinium-based ionic liquids as co-solvents (0.2-1mol%). These new ionic liquids were able to increase the water solubility of these drugs up to four times that in pure water or in an inorganic salt solution. In the presence of these ILs, the drugs lipophilicity (log P was not significantly changed for paracetamol, but for sodium diclofenac it was possible to decrease significantly its lipophilicity. Concerning cytotoxicity in human dermal fibroblasts it was observed that ILs did not show a significant toxicity, and were able to improve cell viability compared with the respective precursors.

Das, K, Beyene BB, Datta A, Garribba E, Roma-Rodrigues C, Silva A, Fernandes AR, Hung C-H.  2018.  EPR and electrochemical interpretation of bispyrazolylacetate anchored Ni(ii) and Mn(ii) complexes: cytotoxicity and anti-proliferative activity towards human cancer cell lines, 2018. New Journal of Chemistry. 42(11):9126-9139. AbstractWebsite

Two mononuclear NiII and MnII compounds, [Ni(bdtbpza)2(CH3OH)4] (1) and [Mn(bdtbpza)2(CH3OH)2(H2O)2] (2), are afforded by employing a ‘scorpionate’ type precursor [bdtbpza = bis(3,5-di-t-butylpyrazol-1-yl)acetate]. The single crystal X-ray structure reveals that the central metal ion (NiII for 1 and MnII for 2) is surrounded by a pair of Oacetate atoms of two bis(pyrazol-1-yl)acetate units, while four OMeOH donors for 1 and two OMeOH plus two Owater for 2 complete the first coordination sphere. Thus, both compounds exhibit a slightly distorted octahedral geometry possessing an O6 coordination environment. EPR spectra of CuII-doped 1 and of 2 recorded on the polycrystalline solids and in organic solution confirm the octahedral geometry around the metal ions and the binding of six oxygen atoms. The electrochemical study of compounds 1 and 2 shows that one electron reduction of MnII occurs at a more negative potential than NiII, indicating a lower tendency of reduction for Mn than Ni. Both compounds displayed a high cytotoxic activity against A2780 ovarian carcinoma cells and no cytotoxic activity in normal primary human fibroblasts for concentrations up to 55 μM. Notwithstanding, compound 1 is found to be the most cytotoxic towards A2780 cancer cells. The cytotoxic activity of compound 1 is correlated with the induction of apoptosis associated with a higher mitochondria dysfunction and autophagy cell death. In addition, the compounds can induce oxidative damage leading to ROS accumulation. Overall, the data presented here demonstrate that 1 has potential for further in vivo studies aiming at its future application in ovarian cancer therapy.

Ribeiro, APC, Anbu S, Alegria ECBA, Fernandes AR, Baptista PV, Mendes R, Matias AS, Mendes M, Guedes da Silva MFC, Pombeiro AJL.  2018.  Evaluation of cell toxicity and DNA and protein binding of green synthesized silver nanoparticles, 2018. Biomed Pharmacother. 101:137-144. AbstractWebsite

Silver nanoparticles (AgNPs) were prepared by GREEN chemistry relying on the reduction of AgNO3 by phytochemicals present in black tea extract. AgNPs were fully characterized by transmission electron microscopy (TEM), ultraviolet-visible spectroscopy ((UV-vis)), X-ray diffraction (XRD) and energy dispersive absorption spectroscopy (EDS). The synthesized AgNPs induced a decrease of the cell viability in a dose-dependent manner with a low IC50 (0.5+/-0.1muM) for an ovarian carcinoma cell line (A2780) compared to primary human fibroblasts (IC50 5.0+/-0.1muM). The DNA binding capability of CT (calf thymus) DNA was investigated using electronic absorption and fluorescence spectroscopies, circular dichroism and viscosity titration methods. Additionally, the AgNPs strongly quench the intrinsic fluorescence of BSA, as determined by synchronous fluorescence spectra.

Roma-Rodrigues, C, Fernandes AR, Baptista PV.  2014.  Exosome in tumour microenvironment: overview of the crosstalk between normal and cancer cells. Biomed Res Int. 2014:179486.14romarodriguesbmri.pdf
Raposo, LR, Silva A, Silva D, Roma-Rodrigues C, Espadinha M, Baptista PV, Santos MMM, Fernandes AR.  2021.  Exploiting the antiproliferative potential of spiropyrazoline oxindoles in a human ovarian cancer cell line, 2021. Bioorganic & Medicinal Chemistry. 30:115880. AbstractWebsite

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.

Oliveira, B, Veigas B, Fernandes AR, Aguas H, Martins R, Fortunato E, Baptista PV.  2020.  Fast Prototyping Microfluidics: Integrating Droplet Digital Lamp for Absolute Quantification of Cancer Biomarkers, 2020. Sensors (Basel). 20(6) AbstractWebsite

Microfluidic (MF) advancements have been leveraged toward the development of state-of-the-art platforms for molecular diagnostics, where isothermal amplification schemes allow for further simplification of DNA detection and quantification protocols. The MF integration with loop-mediated isothermal amplification (LAMP) is today the focus of a new generation of chip-based devices for molecular detection, aiming at fast and automated nucleic acid analysis. Here, we combined MF with droplet digital LAMP (ddLAMP) on an all-in-one device that allows for droplet generation, target amplification, and absolute quantification. This multilayer 3D chip was developed in less than 30 minutes by using a low-cost and extremely adaptable production process that exploits direct laser writing technology in "Shrinky-dinks" polystyrene sheets. ddLAMP and target quantification were performed directly on-chip, showing a high correlation between target concentration and positive droplet score. We validated this integrated chip via the amplification of targets ranging from five to 500,000 copies/reaction. Furthermore, on-chip amplification was performed in a 10 microL volume, attaining a limit of detection of five copies/microL under 60 min. This technology was applied to quantify a cancer biomarker, c-MYC, but it can be further extended to any other disease biomarker.

Bravo, C, Robalo PM, Marques F, Fernandes AR, Sequeira DA, M. Piedade FM, Garcia HM, de Brito MVJ, Morais TS.  2019.  First heterobimetallic Cu(i)–dppf complexes designed for anticancer applications: synthesis, structural characterization and cytotoxicity, 2019. New Journal of Chemistry. 43(31):12308-12317. AbstractWebsite

A new family of eight heterobimetallic Cu(i)–dppf complexes of general formula [Cu(dppf)L][BF4] with dppf = 1,1′-bis(diphenylphosphino)ferrocene and L representing N,N-, N,O- and N,S-heteroaromatic bidentate ligands have been synthesized and fully characterized by classical analytical, spectroscopic and electrochemical methods. The single crystal structures of [Cu(dppf)(pBI)][BF4] (6), [Cu(dppf)(dpytz)][BF4] (7) and [Cu(dppf)(5-Aphen)][BF4] (8) complexes (where pBI = 2-(2-pyridyl)benzimidazole, dpytz = 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine and 5-Aphen = 1,10-phenanthrolin-5-amine) were determined by X-ray diffraction studies. Cytotoxicity of all complexes was evaluated in two human breast adenocarcinoma cell lines (MCF7 and MDAMB231). All the complexes exhibit high cytotoxicity against both human breast cancer cells with IC50 values far lower than those found for the antitumor drug cisplatin in the same cell lines. The IC50 values on primary healthy fibroblasts are of the same order of magnitude as those found for the tumoral cells.

Roma-Rodrigues, C, Rivas-Garcia L, Baptista PV, Fernandes AR.  2020.  Gene Therapy in Cancer Treatment: Why Go Nano?, 2020 Pharmaceutics. 12(3) AbstractWebsite

The proposal of gene therapy to tackle cancer development has been instrumental for the development of novel approaches and strategies to fight this disease, but the efficacy of the proposed strategies has still fallen short of delivering the full potential of gene therapy in the clinic. Despite the plethora of gene modulation approaches, e.g., gene silencing, antisense therapy, RNA interference, gene and genome editing, finding a way to efficiently deliver these effectors to the desired cell and tissue has been a challenge. Nanomedicine has put forward several innovative platforms to overcome this obstacle. Most of these platforms rely on the application of nanoscale structures, with particular focus on nanoparticles. Herein, we review the current trends on the use of nanoparticles designed for cancer gene therapy, including inorganic, organic, or biological (e.g., exosomes) variants, in clinical development and their progress towards clinical applications.

Santos, S, Lanca V, Oliveira H, Silveira L, Marques V, Brito D, Madeira H, Bicho M, Fernandes AR.  2011.  Genetic diagnosis of hypertrophic cardiomyopathy using mass spectrometry DNA arrays and high resolution melting. Rev Port Cardiol. 30(1):7-18.11santosrpc.pdf
Roma-Rodrigues, C, Fernandes AR.  2014.  Genetics of hypertrophic cardiomyopathy: advances and pitfalls in molecular diagnosis and therapy, 2014/10/03. The Application of Clinical Genetics. 7:195-208.: Dove Medical Press AbstractWebsite

Hypertrophic cardiomyopathy (HCM) is a primary disease of the cardiac muscle that occurs mainly due to mutations (>1,400 variants) in genes encoding for the cardiac sarcomere. HCM, the most common familial form of cardiomyopathy, affecting one in every 500 people in the general population, is typically inherited in an autosomal dominant pattern, and presents variable expressivity and age-related penetrance. Due to the morphological and pathological heterogeneity of the disease, the appearance and progression of symptoms is not straightforward. Most HCM patients are asymptomatic, but up to 25% develop significant symptoms, including chest pain and sudden cardiac death. Sudden cardiac death is a dramatic event, since it occurs without warning and mainly in younger people, including trained athletes. Molecular diagnosis of HCM is of the outmost importance, since it may allow detection of subjects carrying mutations on HCM-associated genes before development of clinical symptoms of HCM. However, due to the genetic heterogeneity of HCM, molecular diagnosis is difficult. Currently, there are mainly four techniques used for molecular diagnosis of HCM, including Sanger sequencing, high resolution melting, mutation detection using DNA arrays, and next-generation sequencing techniques. Application of these methods has proven successful for identification of mutations on HCM-related genes. This review summarizes the features of these technologies, highlighting their strengths and weaknesses. Furthermore, current therapeutics for HCM patients are correlated with clinically observed phenotypes and are based on the alleviation of symptoms. This is mainly due to insufficient knowledge on the mechanisms involved in the onset of HCM. Tissue engineering alongside regenerative medicine coupled with nanotherapeutics may allow fulfillment of those gaps, together with screening of novel therapeutic drugs and target delivery systems.

Oliveira, H, Roma-Rodrigues C, Santos A, Veigas B, Bras N, Faria A, Calhau C, de Freitas V, Baptista PV, Mateus N, Fernandes AR, Fernandes I.  2019.  GLUT1 and GLUT3 involvement in anthocyanin gastric transport- Nanobased targeted approach, 2019. Sci Rep. 9(1):789. AbstractWebsite

Anthocyanins may protect against a myriad of human diseases. However few studies have been conducted to evaluate their bioavailability so their absorption mechanism remains unclear. This study aimed to evaluate the role of two glucose transporters (GLUT1 and GLUT3) in anthocyanins absorption in the human gastric epithelial cells (MKN-28) by using gold nanoparticles to silence these transporters. Anthocyanins were purified from purple fleshed sweet potatoes and grape skin. Silencing of GLUT1 and/or GLUT3 mRNA was performed by adding AuNP@GLUT1 and/or AuNP@GLUT3 to MKN-28 cells. Downregulation of mRNA expression occurred concomitantly with the reduction in protein expression. Malvidin-3-O-glucoside (Mv3glc) transport was reduced in the presence of either AuNP@GLUT1 and AuNP@GLUT3, and when both transporters were blocked simultaneously. Peonidin-3-(6'-hydroxybenzoyl)-sophoroside-5-glucoside (Pn3HBsoph5glc) and Peonidin-3-(6'-hydroxybenzoyl-6''-caffeoyl)-sophoroside-5-glucoside (Pn3HBCsoph5glc) were assayed to verify the effect of the sugar moiety esterification at glucose B in transporter binding. Both pigments were transported with a lower transport efficiency compared to Mv3glc, probably due to steric hindrance of the more complex structures. Interestingly, for Pn3HBCsoph5glc although the only free glucose is at C5 and the inhibitory effect of the nanoparticles was also observed, reinforcing the importance of glucose on the transport regardless of its position or substitution pattern. The results support the involvement of GLUT1 and GLUT3 in the gastric absorption of anthocyanins.

Cordeiro, M, Carvalho L, Silva J, Saúde L, Fernandes AR, Baptista. PV.  2017.  Gold nanobeacons for tracking gene silencing in Zebrafish. Nanomaterials. AbstractWebsite

The use of gold nanoparticles for effective gene silencing has demonstrated its potential as a tool for gene expression experiments and for the treatment of several diseases. Here, we used a gold nanobeacon designed to specifically silence the enhanced green fluorescence protein (EGFP) mRNA in embryos of a fli-EGFP transgenic zebrafish line, while simultaneously allowing the tracking and localization of the silencing events via the beacon’s emission. Fluorescence imaging measurements demonstrated a decrease of the EGFP emission with a concomitant increase in the fluorescence of the Au-nanobeacon. Furthermore, microinjection of the Au-nanobeacon led to a negligible difference in mortality and malformations in comparison to the free oligonucleotide, indicating that this system is a biocompatible platform for the administration of gene silencing moieties. Together, these data illustrate the potential of Au-nanobeacons as tools for in vivo zebrafish gene modulation with low toxicity which may be used towards any gene of interest.