Publications

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2018
Synthesis, Cytotoxicity Evaluation in Human Cell Lines and in Vitro DNA Interaction of a Hetero-Arylidene-9(10H)-Anthrone, Peixoto, Daniela, Figueiredo Margarida, Malta Gabriela, Roma-Rodrigues Catarina, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Barroso Sónia, Carvalho {Ana Luísa}, Afonso {Carlos A. M. }, Ferreira {Luisa M. }, and Branco {Paula S. } , European Journal of Organic Chemistry, jan, Volume 2018, Number 4, p.545–549, (2018) Abstract

A new and never before reported hetero-arylidene-9(10H)-anthrone structure (4) was unexpectedly isolated on reaction of 1,2-dimethyl-3-ethylimidazolium iodide (2) and 9-anthracenecarboxaldehyde (3) under basic conditions. Its structure was unequivocally confirmed by X-ray crystallography. No cytotoxicity in human healthy fibroblasts and in two different cancer cell lines was observed, indicating its applicability in biological systems. Compound 4 interacts with CT-DNA by intercalation between the adjacent base pairs of DNA with a high binding affinity [Kb = 2.0 (±0.20) × 105 m–1], which is 10 × higher than that described for doxorubicin [Kb = 3.2 (±0.23) × 104 m–1]. Furthermore, compound 4 quenches the fluorescence emission of a GelRed–CT-DNA system with a quenching constant (KSV) of 3.3 (±0.3) × 103 m–1 calculated by the Stern–Volmer equation.

Nanoparticle-AntagoMIR based targeting of MIR-31 to induce osterix and osteocalcin expression in mesenchymal stem cells, McCully, Mark, Conde João, Baptista {Pedro V. }, Mullin Margaret, Dalby {Matthew J. }, and Berry {Catherine C. } , PLoS ONE, feb, Volume 13, Number 2, (2018) Abstract

Mesenchymal stem cells are multipotent adult stem cells capable of generating bone, cartilage and fat, and are thus currently being exploited for regenerative medicine. When considering osteogenesis, developments have been made with regards to chemical induction (e.g. differentiation media) and physical induction (e.g. material stiffness, nanotopography), targeting established early transcription factors or regulators such as runx2 or bone morphogenic proteins and promoting increased numbers of cells committing to osteo-specific differentiation. Recent research highlighted the involvement of microRNAs in lineage commitment and terminal differentiation. Herein, gold nanoparticles that confer stability to short single stranded RNAs were used to deliver MiR-31 antagomiRs to both pre-osteoblastic cells and primary human MSCs in vitro. Results showed that blocking miR-31 led to an increase in osterix protein in both cell types at day 7, with an increase in osteocalcin at day 21, suggesting MSC osteogenesis. In addition, it was noted that antagomiR sequence direction was important, with the 5 prime reading direction proving more effective than the 3 prime. This study highlights the potential that miRNA antagomiR-Tagged nanoparticles offer as novel therapeutics in regenerative medicine.

Combination of chemotherapy and Au-nanoparticle photothermy in the visible light to tackle doxorubicin resistance in cancer cells, Pedrosa, Pedro, Mendes Rita, Cabral Rita, Martins {Luísa M. D. R. S. }, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Scientific Reports, dec, Volume 8, Number 1, (2018) Abstract

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.

2017
Immortalization and characterization of a new canine mammary tumour cell line FR37-CMT, Raposo, {L. R. }, Roma-Rodrigues C., Faísca P., Alves M., Henriques J., Carvalheiro {M. C. }, Corvo {M. L. }, Baptista {P. V. }, Pombeiro {A. J. }, and Fernandes {A. R. } , Veterinary and Comparative Oncology, sep, Volume 15, Number 3, p.952–967, (2017) Abstract

Here we describe the establishment of a new canine mammary tumour (CMT) cell line, FR37-CMT that does not show dependence on female hormonal signaling to induce tumour xenografts in NOD-SCID mice. FR37-CMT cell line has a stellate or fusiform shape, displays the ability to reorganize the collagen matrix, expresses vimentin, CD44 and shows the loss of E-cadherin which is considered a fundamental event in epithelial to mesenchymal transition (EMT). The up-regulation of ZEB1, the detection of phosphorylated ERK1/2 and the downregulation of DICER1 and miR-200c are also in accordance with the mesenchymal characteristics of FR37-CMT cell line. FR37-CMT shows a higher resistance to cisplatin (IC50>50 µM) and to doxorubicin (IC50>5.3 µM) compared with other CMT cell lines. These results support the use of FR37-CMT as a new CMT model that may assist the understanding of the molecular mechanisms underlying EMT, CMT drug resistance, fostering the development of novel therapies targeting CMT.

A digital microfluidics platform for loop-mediated isothermal amplification detection, Coelho, {Beatriz Jorge}, Veigas Bruno, Águas Hugo, Fortunato Elvira, Martins Rodrigo, Baptista {Pedro Viana}, and Igreja Rui , Sensors, nov, Volume 17, Number 11, (2017) Abstract

Digital microfluidics (DMF) arises as the next step in the fast-evolving field of operation platforms for molecular diagnostics. Moreover, isothermal schemes, such as loop-mediated isothermal amplification (LAMP), allow for further simplification of amplification protocols. Integrating DMF with LAMP will be at the core of a new generation of detection devices for effective molecular diagnostics at point-of-care (POC), providing simple, fast, and automated nucleic acid amplification with exceptional integration capabilities. Here, we demonstrate for the first time the role of coupling DMF and LAMP, in a dedicated device that allows straightforward mixing of LAMP reagents and target DNA, as well as optimum temperature control (reaction droplets undergo a temperature variation of just 0.3°C, for 65°C at the bottom plate). This device is produced using low-temperature and low-cost production processes, adaptable to disposable and flexible substrates. DMF-LAMP is performed with enhanced sensitivity without compromising reaction efficacy or losing reliability and efficiency, by LAMP-amplifying 0.5 ng/µL of target DNA in just 45 min. Moreover, on-chip LAMP was performed in 1.5 µL, a considerably lower volume than standard bench-top reactions.

Quantitative real-time monitoring of RCA amplification of cancer biomarkers mediated by a flexible ion sensitive platform, Veigas, Bruno, Pinto Joana, Vinhas Raquel, Calmeiro Tomás, Martins Rodrigo, Fortunato Elvira, and Baptista {Pedro Viana} , Biosensors & Bioelectronics, may, Volume 91, p.788–795, (2017) Abstract

Ion sensitive field-effect transistors (ISFET) are the basis of radical new sensing approaches. Reliable molecular characterization of specific detection of DNA and/or RNA is vital for disease diagnostics and to follow up alterations in gene expression profiles. Devices and strategies for biomolecular recognition and detection should be developed into reliable and inexpensive platforms. Here, we describe the development of a flexible thin-film sensor for label free gene expression analysis. A charge modulated ISFET based sensor was integrated with real-time DNA/RNA isothermal nucleic acid amplification: Loop-mediated isothermal amplification (LAMP) and Rolling Circle Amplification (RCA) techniques for c-MYC and BCR-ABL1 genes, allowing for the real-time quantification of template. Also, RCA allowed the direct quantification of RNA targets at room temperature, eliminating the requirement for external temperature controllers and overall complexity of the molecular diagnostic approach. This integration between the biological and the sensor/electronic approaches enabled the development of an inexpensive and direct gene expression-profiling platform.

Digital microfluidics for nucleic acid amplification, Coelho, Beatriz, Veigas Bruno, Fortunato Elvira, Martins Rodrigo, Águas Hugo, Igreja Rui, and Baptista {Pedro V. } , Sensors, jul, Volume 17, Number 7, (2017) Abstract

Digital Microfluidics (DMF) has emerged as a disruptive methodology for the control and manipulation of low volume droplets. In DMF, each droplet acts as a single reactor, which allows for extensive multiparallelization of biological and chemical reactions at a much smaller scale. DMF devices open entirely new and promising pathways for multiplex analysis and reaction occurring in a miniaturized format, thus allowing for healthcare decentralization from major laboratories to point-of-care with accurate, robust and inexpensive molecular diagnostics. Here, we shall focus on DMF platforms specifically designed for nucleic acid amplification, which is key for molecular diagnostics of several diseases and conditions, from pathogen identification to cancer mutations detection. Particular attention will be given to the device architecture, materials and nucleic acid amplification applications in validated settings.

Gold nanobeacons for tracking gene silencing in zebrafish, Cordeiro, Milton, Carvalho Lara, Silva Joana, Saúde Leonor, Fernandes {Alexandra R. }, and Baptista {Pedro V. } , Nanomaterials, jan, Volume 7, Number 1, (2017) Abstract

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.

Gold nanoparticles in molecular diagnostics and molecular therapeutics, Matias, {Ana S. }, Carlos {Fábio F. }, Pedrosa P., Fernandes {Alexandra R. }, and Baptista {Pedro V. } , Metal Nanoparticles in Pharma, jan, Switzerland, p.365–387, (2017) Abstract

Gold nanoparticles, due to their unique physicochemical properties, are among the most widely used nanoscale-based platforms for molecular diagnostics. The intrinsic chemical stability and apparent lack of toxicity have also prompted for application in therapeutics, e.g., for imaging modalities and as vectorization strategies for molecular modulators, i.e., gene silencing, specific targeting of cellular pathways, etc. Because of their common molecular ground, these approaches have been synergistically coupled together into molecular theranostic systems that allow for radical new in vivo diagnostics modalities with simultaneous tackling of molecular disequilibria leading to disease. Despite this tremendous potential, gold nanoparticle- based systems still have to make their effective translation to the clinics. This chapter focuses on the use of gold nanoparticles for molecular diagnostics and molecular therapeutics and their application in theranostics. Attention is paid to those systems that have moved toward the clinics.

Multifunctional gold-nanoparticles: A nanovectorization tool for the targeted delivery of novel chemotherapeutic agents, Fernandes, {Alexandra R. }, Jesus João, Martins Pedro, Figueiredo Sara, Rosa Daniela, Martins {Luísa M. R. D. R. S. }, Corvo {Maria Luísa}, Carvalheiro {Manuela C. }, Costa {Pedro M. }, and Baptista {Pedro V. } , Journal of Controlled Release, jan, Volume 245, p.52–61, (2017) Abstract

Due to their small size and unique properties, multifunctional nanoparticles arise as versatile delivery systems easily grafted with a vast array of functional moieties, such as anticancer cytotoxic chemotherapeutics and targeting agents. Here, we formulated a multifunctional gold-nanoparticle (AuNP) system composed of a monoclonal antibody against epidermal growth factor receptor (EGFR) (anti-EGFR D-11) for active targeting and a Co(II) coordination compound [CoCl(H2O)(phendione)2][BF4] (phendione = 1,10-phenanthroline-5,6-dione) (TS265) with proven antiproliferative activity towards cancer cells (designated as TargetNanoTS265). The efficacy of this nanoformulation, and the non-targeted counterpart (NanoTS265), were evaluated in vitro using cancer cell models and in vivo using mice xenografts. Compared to the free compound, both nanoformulations (TargetNanoTS265 and NanoTS265) efficiently delivered the cytotoxic cargo in a controlled selective manner due to the active targeting, boosting tumor cytotoxicity. Treatment of HCT116-derived xenografts tumors with TargetNanoTS265 led to 93% tumor reduction. This simple conceptual nanoformulation demonstrates the potential of nanovectorization of chemotherapeutics via simple assembly onto AuNPs of BSA/HAS-drug conjugates that may easily be expanded to suit other cargo of novel compounds that require optimized controlled delivery to cancer target.

Tumor microenvironment modulation via gold nanoparticles targeting malicious exosomes: Implications for cancer diagnostics and therapy, Roma-Rodrigues, Catarina, Raposo {Luís R. }, Cabral Rita, Paradinha Fabiana, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , International Journal of Molecular Sciences, jan, Volume 18, Number 1, (2017) Abstract

Exosomes are nanovesicles formed in the endosomal pathway with an important role in paracrine and autocrine cell communication. Exosomes secreted by cancer cells, malicious exosomes, have important roles in tumor microenvironment maturation and cancer progression. The knowledge of the role of exosomes in tumorigenesis prompted a new era in cancer diagnostics and therapy, taking advantage of the use of circulating exosomes as tumor biomarkers due to their stability in body fluids and targeting malignant exosomes’ release and/or uptake to inhibit or delay tumor development. In recent years, nanotechnology has paved the way for the development of a plethora of new diagnostic and therapeutic platforms, fostering theranostics. The unique physical and chemical properties of gold nanoparticles (AuNPs) make them suitable vehicles to pursuit this goal. AuNPs’ properties such as ease of synthesis with the desired shape and size, high surface:volume ratio, and the possibility of engineering their surface as desired, potentiate AuNPs’ role in nanotheranostics, allowing the use of the same formulation for exosome detection and restraining the effect of malicious exosomes in cancer progression.

Allele specific LAMP- gold nanoparticle for characterization of single nucleotide polymorphisms, Carlos, {Fábio Ferreira}, Veigas Bruno, Matias {Ana S. }, c}alo Dória Gon{\c, Flores Orfeu, and Baptista {Pedro V. } , Biotechnology Reports, dec, Volume 16, p.21–25, (2017) Abstract

Due to their relevance as disease biomarkers and for diagnostics, screening of single nucleotide polymorphism (SNPs) requires simple and straightforward strategies capable to provide results in medium throughput settings. Suitable approaches relying on isothermal amplification techniques have been evolving to substitute the cumbersome and highly specialized PCR amplification detection schemes. Nonetheless, identification of an individual's genotype still requires sophisticated equipment and laborious methods. Here, we present a low-cost and reliable approach based on the allele specific loop-mediated isothermal amplification (AS-LAMP) coupled to ssDNA functionalized gold nanoparticle (Au-nanoprobe) colorimetric sequence discrimination. The Au-nanoprobe integration allows for the colorimetric detection of AS-LAMP amplification product that can be easily interpreted in less than 15 min. We targeted a clinical relevant SNP responsible for lactose intolerance (-13910C/T dbSNP rs#: 4988235) to demonstrate its proof of concept and full potential of this novel approach.

Current trends in molecular diagnostics of chronic myeloid leukemia, Vinhas, Raquel, Cordeiro Milton, Pedrosa Pedro, Fernandes {Alexandra R. }, and Baptista {Pedro V. } , Leukemia & Lymphoma, aug, Volume 58, Number 8, p.1791–1804, (2017) Abstract

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.

2016
BioCode gold-nanobeacon for the detection of fusion transcripts causing chronic myeloid leukemia, Cordeiro, M., Giestas L., Lima {J. C. }, and Baptista {P. M. V. } , Journal of Nanobiotechnology, may, Volume 14, Number 1, (2016) Abstract

BACKGROUND: Gold-nanobeacons (Au-nanobeacons) have proven to be versatile systems for molecular diagnostics and therapeutic actuators. Here, we present the development and characterization of two gold nanobeacons combined with Förster resonance energy transfer (FRET) based spectral codification for dual mode sequence discrimination. This is the combination of two powerful technologies onto a single nanosystem.RESULTS: We proved this concept to detect the most common fusion sequences associated with the development of chronic myeloid leukemia, e13a2 and e14a2. The detection is based on spectral shift of the donor signal to the acceptor, which allows for corroboration of the hybridization event. The Au-nanobeacon acts as scaffold for detection of the target in a homogenous format whose output capability (i.e. additional layer of information) is potentiated via the spectral codification strategy.CONCLUSIONS: The spectral coded Au-nanobeacons permit the detection of each of the pathogenic fusion sequences, with high specificity towards partial complementary sequences. The proposed BioCode Au-nanobeacon concept provides for a nanoplatform for molecular recognition suitable for cancer diagnostics.

Non-small cell lung cancer biomarkers and targeted therapy - two faces of the same coin fostered by nanotechnology, Mendes, Rita, Carreira Bárbara, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Expert Review of Precision Medicine and Drug Development, mar, Volume 1, Number 2, p.155–168, (2016) Abstract

Lung cancer is the leading cause of cancer-related mortality in the world, non-small lung cancer (NSCLC) is the most frequent subtype (85% of the cases). Within this subtype, adenocarcinoma and squamous cell carcinoma are the most frequent. New therapeutic strategies based on targeted delivery of drugs have relied on the use of biomarkers derived from the patients’ molecular profiling. Several biomarkers have been found to be useful for use as targets for precision therapy in NSCLC, such as mutations in the epidermal growth factor receptor, v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog, anaplastic lymphoma kinase, mesenchymal-epithelial transition factor receptor tyrosine kinase, BRAF, c-ros oncogene 1, P53 and phosphatase with tensin homology. Current developments in Nanomedicine have allowed for multifunctional systems capable of delivering therapeutics with increased precision to the target site/tissue, while simultaneously assisting in diagnosis. Here, we review the use of biomarkers in nanotechnology translation in NSCLC management.

A novel mutation in CEBPA gene in a patient with acute myeloid leukemia, Vinhas, Raquel, Tolmatcheva Anna, Canto Rafaela, Ribeiro Patricia, Lourenco Alexandra, {de Sousa} {Aida Botelho}, Baptista {Pedro Miguel Ribeiro Viana}, and de Fernandes {Maria Alexandra Núncio Carvalho Ramos} , Leukemia & Lymphoma, mar, Volume 57, Number 3, p.711–713, (2016) Abstract
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Colorimetric assessment of BCR-ABL1 transcripts in clinical samples via gold nanoprobes, Vinhas, Raquel, Correia Claudia, Ribeiro Patricia, Lourenco Alexandra, {de Sousa} {Aida Botelho}, de Fernandes {Maria Alexandra Núncio Carvalho Ramos}, and Baptista {Pedro Miguel Ribeiro Viana} , Analytical and Bioanalytical Chemistry, jul, Volume 408, Number 19, p.5277–5284, (2016) Abstract

Gold nanoparticles functionalized with thiolated oligonucleotides (Au-nanoprobes) have been used in a range of applications for the detection of bioanalytes of interest, from ions to proteins and DNA targets. These detection strategies are based on the unique optical properties of gold nanoparticles, in particular, the intense color that is subject to modulation by modification of the medium dieletric. Au-nanoprobes have been applied for the detection and characterization of specific DNA sequences of interest, namely pathogens and disease biomarkers. Nevertheless, despite its relevance, only a few reports exist on the detection of RNA targets. Among these strategies, the colorimetric detection of DNA has been proven to work for several different targets in controlled samples but demonstration in real clinical bioanalysis has been elusive. Here, we used a colorimetric method based on Au-nanoprobes for the direct detection of the e14a2 BCR-ABL fusion transcript in myeloid leukemia patient samples without the need for retro-transcription. Au-nanoprobes directly assessed total RNA from 38 clinical samples, and results were validated against reverse transcription-nested polymerase chain reaction (RT-nested PCR) and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The colorimetric Au-nanoprobe assay is a simple yet reliable strategy to scrutinize myeloid leukemia patients at diagnosis and evaluate progression, with obvious advantages in terms of time and cost, particularly in low- to medium-income countries where molecular screening is not routinely feasible.

Editorial: Cancer Nanotheranostics: What Have We Learned So Far?, Conde, João, Tian Furong, {de la Fuente} {Jesus M. }, and Baptista {Pedro Miguel Ribeiro Viana} , Frontiers in Chemistry, jan, Volume 3, (2016) Abstract
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Gold nanoparticles for diagnostics: Advances towards points of care, Cordeiro, Milton, Pedrosa Pedro, Carlos {Fábio Ferreira}, Lopez António, and Baptista {Pedro Viana} , Diagnostics, dec, Volume 6, Number 4, (2016) Abstract

The remarkable physicochemical properties of gold nanoparticles (AuNPs) have prompted developments in the exploration of biomolecular interactions with AuNP-containing systems, in particular for biomedical applications in diagnostics. These systems show great promise in improving sensitivity, ease of operation and portability. Despite this endeavor, most platforms have yet to reach maturity and make their way into clinics or points of care (POC). Here, we present an overview of emerging and available molecular diagnostics using AuNPs for biomedical sensing that are currently being translated to the clinical setting.

Infection of human keratinocytes by Streptococcus dysgalactiae subspecies dysgalactiae isolated from milk of the bovine udder, Roma-Rodrigues, Catarina, Alves-Barroco Cynthia, Raposo {Luis R. }, Costa {Mafalda N. }, Fortunato Elvira, Baptista {Pedro Miguel Ribeiro Viana}, de Fernandes {Maria Alexandra Núncio Carvalho Ramos}, and Santos-Sanches Ilda , Microbes And Infection, apr, Volume 18, Number 4, p.290–293, (2016) Abstract

Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) are considered exclusive animal pathogens; however, a putative zoonotic upper limb cellulitis, a prosthetic joint infection and an infective endocarditis were described in humans. To unravel if bovine SDSD isolates are able to infect human cells, the adherence and internalization to human primary keratinocytes of two bovine SDSD strains isolated from milk collected from udder were analyzed. Bacterial adhesion assays and confocal microscopy indicate a high adherence and internalization of SDSD isolates to human cells, suggesting for the first time the ability of bovine isolates to infect human cells. (C) 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

In vitro and in vivo biological characterization of the anti-proliferative potential of a cyclic trinuclear organotin(IV) complex, Martins, Marta, Baptista P. V., Mendo {Ana Soraia}, Correia C., Videira Paula, Rodrigues A. S., Muthukumaran Jayaraman, Santos-Silva Teresa, Silva Ana, {Guedes da Silva} Fatima {M. C. }, Gigante Joana, Duarte Antonio, Gajewska Malgorzata, and Fernandes A. R. , Molecular Biosystems, Volume 12, Number 3, p.1015–1023, (2016) Abstract

Identification of novel molecules that can selectively inhibit the growth of tumor cells, avoid causing side effects to patients and/or intrinsic or acquired resistance, usually associated with common chemotherapeutic agents, is of utmost importance. Organometallic compounds have gained importance in oncologic chemotherapy, such as organotin(IV) complexes. In this study, we assessed the anti-tumor activity of the cyclic trinuclear organotin(IV) complex with an aromatic oximehydroxamic acid group [nBu(2)Sn(L)](3)(H2L = N,2-dihydroxy-5-[N-hydroxyethanimidoyl]benzamide) - MG85 - and provided further characterization of its biological targets. We have previously shown the high anti-proliferative activity of this complex against human colorectal and hepatocellular carcinoma cell lines and lower cytotoxicity in neonatal non-tumor fibroblasts. MG85 induces tumor cell apoptosis and down-regulation of proteins related to tubulin dynamics (TCTP and COF1). Further characterization included the: (i) evaluation of interference in the cell cycle progression, including the expression of critical genes; (ii) affinity to DNA and the corresponding mode of binding; (iii) genotoxic potential in cells with deficient DNA repair pathways; and (iv) in vivo tumor reduction efficiency using mouse colorectal carcinoma xenografts.

2015
Characterization of antiproliferative potential and biological targets of a copper compound containing 4'-phenyl terpyridine, Mendo, {Ana Soraia}, Figueiredo Sara, Roma-Rodrigues Catarina, Videira {Paula A. }, Ma Zhen, Diniz Mario, Larguinho Miguel, Costa P. M., Lima {Joao C. }, Pombeiro {Armando J. L. }, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , JBIC Journal of Biological Inorganic Chemistry, sep, Volume 20, Number 6, p.935–948, (2015) Abstract

Several copper complexes have been assessed as anti-tumor agents against cancer cells. In this work, a copper compound [Cu(H2O){OS(CH3)(2)}L](NO3)(2) incorporating the ligand 4'-phenyl-terpyridine antiproliferative activity against human colorectal, hepatocellular carcinomas and breast adenocarcinoma cell lines was determined, demonstrating high cytotoxicity. The compound is able to induce apoptosis and a slight delay in cancer cell cycle progression, probably by its interaction with DNA and induction of double-strand pDNA cleavage, which is enhanced by oxidative mechanisms. Moreover, proteomic studies indicate that the compound induces alterations in proteins involved in cytoskeleton maintenance, cell cycle progression and apoptosis, corroborating its antiproliferative potential.

Gold nanoparticles for DNA/RNA-based diagnostics, Franco, Ricardo, Pedrosa Pedro, Carlos {Fábio Ferreira}, Veigas Bruno, and Baptista {Pedro Miguel Ribeiro Viana} , Handbook of Nanoparticles, sep, Switzerland, p.1339–1370, (2015) Abstract

The remarkable physicochemical properties of gold nanoparticles (AuNPs) have prompted development in exploring biomolecular interactions with AuNPscontaining systems, pursuing biomedical applications in diagnostics. Among these applications, AuNPs have been remarkably useful for the development of DNA/RNA detection and characterization systems for diagnostics, including systems suitable for point of need. Here, emphasis will be on available molecular detection schemes of relevant pathogens and their molecular characterization, genomic sequences associated with medical conditions (including cancer), mutation and polymorphism identification, and the quantification of gene expression.

Nanoparticles for mass spectrometry applications, Larguinho, Miguel, Capelo {José Luís}, and Baptista {Pedro V. } , Handbook of Nanoparticles, sep, Switzerland, p.1371–1396, (2015) Abstract

Nanotechnology has led to the development of new and improved materials, and particular emphasis has been directed toward nanoparticles and their multiple bio-applications. Nanoparticles exhibit size-, shape-, and compositiondependent properties, e.g., surface plasmon resonance and photothermal properties, which may potentially enhance laser desorption/ionization systems for mass spectrometry-based analysis of biomolecules. Also, nanoparticles possess high surface to volume ratio that can be easily derivatized with a wide range of ligands with different functional groups. Surface modification makes nanoparticles advantageous for sample preparation procedures prior to detection by mass spectrometry. Moreover, it allows the synthesis of affinity probes, which promotes interactions between nanoparticles and analytes, greatly enhancing the ionization efficiency. This chapter provides a comprehensive discussion on the use of nanoparticles for mass spectrometry-related applications, from sample preparation methodologies to ionization surfaces. Applications will focus on nanoparticle size, composition, and functionalization, as a comparative point of view on optimal characteristics toward maximization of bioassay efficiency.

Gold nanoprobe-based non-crosslinking hybridization for molecular diagnostics, Larguinho, Miguel, Canto Rafaela, Cordeiro Milton, Pedrosa Pedro, Fortuna Andreia, Vinhas Raquel, and Baptista {Pedro Miguel Ribeiro Viana} , Expert Review Of Molecular Diagnostics, oct, Volume 15, Number 10, p.1355–1368, (2015) Abstract

Non-crosslinking (NCL) approaches using DNA-modified gold nanoparticles for molecular detection constitute powerful tools with potential implications in clinical diagnostics and tailored medicine. From detection of pathogenic agents to identification of specific point mutations associated with health conditions, these methods have shown remarkable versatility and simplicity. Herein, the NCL hybridization assay is broken down to the fundamentals behind its assembly and detection principle. Gold nanoparticle synthesis and derivatization is addressed, emphasizing optimal size homogeneity and conditions for maximum surface coverage, with direct implications in downstream detection. The detection principle is discussed and the advantages and drawbacks of different NCL approaches are discussed. Finally, NCL-based applications for molecular detection of clinically relevant loci and potential integration into more complex biosensing platforms, projecting miniaturization and portability are addressed.