Publications

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2024
Anti-inflammatory and antiproliferative activity of Helichrysum odoratissimum sweet. Against lung cancer, Esmear, Tenille, Twilley Danielle, Thipe {Velaphi Clement}, Katti {Kattesh V. }, Mandiwana Vusani, Kalombo {Michel Lonji}, Ray {Suprakas Sinha}, Rikhotso-Mbungela Rirhandzu, Bovilla {Venugopal Reddy}, Madhunapantula {Subba Rao}, Langhanshova Lenka, Roma-Rodrigues Catarina, Fernandes {Alexandra R. }, Baptista Pedro, Hlati Silvestre, Pretorius Judey, and Lall Namrita , South African Journal of Botany, Volume 166, p.525–538, (2024) Abstract

Lung cancer remains the top killing cancer worldwide despite advances in treatment. Seven ethanolic plant extracts were selected and evaluated for their antiproliferative activity against the two main types of lung cancers: non-small cell (A549) and small cell lung cancer cells (SHP-77). An ethanolic extract of Helichrysum odoratissimum Sweet (HO) showed significant antiproliferative activity against lung cancer, with a fifty percent inhibitory concentration (IC50) of 83.43 ± 1.60 µg/mL (A549), 49.46 ± 0.48 µg/mL (SHP-77) and 50.71 ± 2.27 µg/mL, against normal lung epithelial cells (MRC-5), resulting in a selectivity index (SI) value of 0.61 on A549 cells and 1.03 on SHP-77 cells, which was compared to the positive drug control, actinomycin D where the SI values were found to be 2 and 0.25 against A549 and SHP-77 cells, respectively. Against murine macrophages (RAW 264.7) and hepatocytes (HepG2), the HO ethanolic extract showed IC50 values of 60.15 ± 1.98 µg/mL and 23.61 ± 1.06 µg/mL, respectively. Microscopy showed that the HO ethanolic extract induced apoptosis in the A549 and HepG2 cells at 50 µg/mL and 300 µg/mL, respectively. The HO ethanolic extract, furthermore, inhibited the pro-inflammatory enzymes, cyclooxygenase 2 (COX-2) and 5-lipoxygenase (5-LOX) with IC50 values of 7.94 ± 3.84 µg/mL and 2.08 ± 1.35 µg/mL, respectively, whereas the positive controls Ibuprofen (COX-2) and Zileuton (5-LOX) showed IC50 values of 0.85 ± 0.14 µg/mL and 0.06 ± 0.05 µg/mL, respectively. The activity of NAD(P)H quinone oxidoreductase-1 (NQO1), which is a direct target of nuclear factor erythroid-2-related factor-2 (NRF2), was significantly inhibited in the A549 cells by the HO ethanolic extract (at 125 µg/mL) when compared to the positive control, brusatol (at 500 nM). Using the ex ovo yolk sac membrane (YSM) assay, the HO ethanolic extract (at 18.5 µg/egg) showed a 31.65 ± 12.80% inhibition of blood vessel formation. This is the first report of the noteworthy antiproliferative activity of the HO ethanolic extract on lung cancer cells including its potential to target several enzymes associated with inflammation and therefore, should be considered for further analysis.

2020
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.

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.

Potentiating angiogenesis arrest in vivo via laser irradiation of peptide functionalised gold nanoparticles, Pedrosa, Pedro, Heuer-Jungemann Amelie, Kanaras {Antonios G. }, Fernandes {Alexandra R. }, and Baptista {Pedro V. } , Journal of Nanobiotechnology, nov, Volume 15, Number 1, (2017) Abstract

Background: Anti-angiogenic therapy has great potential for cancer therapy with several FDA approved formulations but there are considerable side effects upon the normal blood vessels that decrease the potential application of such therapeutics. Chicken chorioallantoic membrane (CAM) has been used as a model to study angiogenesis in vivo. Using a CAM model, it had been previously shown that spherical gold nanoparticles functionalised with an anti-angiogenic peptide can humper neo-angiogenesis. Results: Our results show that gold nanoparticles conjugated with an anti-angiogenic peptide can be combined with visible laser irradiation to enhance angiogenesis arrest in vivo. We show that a green laser coupled to gold nanoparticles can achieve high localized temperatures able to precisely cauterize blood vessels. This combined therapy acts via VEGFR pathway inhibition, leading to a fourfold reduction in FLT-1 expression. Conclusions: The proposed phototherapy extends the use of visible lasers in clinics, combining it with chemotherapy to potentiate cancer treatment. This approach allows the reduction of dose of anti-angiogenic peptide, thus reducing possible side effects, while destroying blood vessels supply critical for tumour progression.

2016
Peptide-coated gold nanoparticles for modulation of angiogenesis in vivo, Roma-Rodrigues, Catarina, Heuer-Jungemann Amelie, de Fernandes {Maria Alexandra Núncio Carvalho Ramos}, Kanaras {Antonios G. }, and Baptista {Pedro Miguel Ribeiro Viana} , International journal of nanomedicine, Volume 11, p.2633–2639, (2016) Abstract

In this work, peptides designed to selectively interact with cellular receptors involved in the regulation of angiogenesis were anchored to oligo-ethylene glycol-capped gold nanoparticles (AuNPs) and used to evaluate the modulation of vascular development using an ex ovo chick chorioallantoic membrane assay. These nanoparticles alter the balance between naturally secreted pro- and antiangiogenic factors, under various biological conditions, without causing toxicity. Exposure of chorioallantoic membranes to AuNP-peptide activators of angiogenesis accelerated the formation of new arterioles when compared to scrambled peptide-coated nanoparticles. On the other hand, antiangiogenic AuNP-peptide conjugates were able to selectively inhibit angiogenesis in vivo. We demonstrated that AuNP vectorization is crucial for enhancing the effect of active peptides. Our data showed for the first time the effective control of activation or inhibition of blood vessel formation in chick embryo via AuNP-based formulations suitable for the selective modulation of angiogenesis, which is of paramount importance in applications where promotion of vascular growth is desirable (eg, wound healing) or ought to be contravened, as in cancer development.

2015
Significance of the balance between intracellular glutathione and polyethylene glycol for successful release of small interfering RNA from gold nanoparticles, McCully, Mark, Hernandez Yulan, Conde João, Baptista {Pedro Miguel Ribeiro Viana}, {de la Fuente} {Jesus M. }, Hursthouse Andrew, Stirling David, and Berry {Catherine C. } , Nano Research, oct, Volume 8, Number 10, p.3281–3292, (2015) Abstract

The therapeutic promise of small interfering RNAs (siRNAs) for specific gene silencing is dependent on the successful delivery of functional siRNAs to the cytoplasm. Their conjugation to an established delivery platform, such as gold nanoparticles, offers tremendous potential for treating diseases and advancing our understanding of cellular processes. Their success or failure is dependent on both the uptake of the nanoparticles into the cells and subsequent intracellular release of the functional siRNA. In this study, utilizing gold nanoparticle siRNA-mediated delivery against C-MYC, we aimed to determine if we could achieve knockdown in a cancer cell line with low levels of intracellular glutathione, and determine the influence, if any, of polyethylene glycol (PEG) ligand density on knockdown, with a view to determining the optimal nanoparticle design to achieve C-MYC knockdown. We demonstrate that, regardless of the PEG density, knockdown in cells with relatively low glutathione levels can be achieved, as well as the possible effect of steric hindrance of PEG on the availability of the siRNA for cleavage in the intracellular environment. Gold nanoparticle uptake was demonstrated via transmission electron microscopy and mass spectroscopy, while knockdown was determined at the protein and physiological levels (cells in S-phase) by in-cell westerns and BrdU incorporation, respectively.

Mobile based gold nanoprobe TB diagnostics for point-of-need, Veigas, B., Fortunato E., and Baptista {P. V. } , Mobile Health Technologies: Methods and Protocols, jan, Volume Part 1, United States, p.41–56, (2015) Abstract

Nanotechnology based diagnostics has provided improved tools for pathogen detection and sensitive and specific characterization of antibiotic resistance signatures. Tuberculosis (TB) is caused by members of the Mycobacterium tuberculosis Complex (MTBC) and, according to the World Health Organization, is one of the most serious infectious diseases in the world. Recent advances in molecular diagnostics of TB have improved both the detection time and sensitivity but they still require specialized technical personnel and cumbersome laboratory equipment. Diagnostics at point-of-need is crucial to TB control as it may provide rapid identification of pathogen together with the resistance profile of TB strains, originated from single nucleotide polymorphisms (SNPs) in different loci , allowing for a more accurate indication of the adequate therapy.Gold nanoparticles have been widely used in molecular diagnostics platforms. Here, we describe the use of gold nanoprobes (oligonucleotide functionalized gold nanoparticles) to be used in a non-crosslinking colorimetric method for the direct detection of specific DNA targets. Due to the remarkable optical properties of gold nanoparticles, this detection system provides colorimetric detection of the pathogen together with the potential of identification of several single nucleotide polymorphisms (SNPs) involved in TB resistance to antibiotics. For point-of-need use, we adapted this strategy to a low-cost mobile scheme using a paper based revelation platform and where the spectral signature is transposed to RGB data via a smartphone device. This way, identification of pathogen and characterization of resistance signatures is achieved at point-of-need.

15 years on siRNA delivery: Beyond the State-of-the-Art on inorganic nanoparticles for RNAi therapeutics, Conde, João, Ambrosone Alfredo, Hernandez Yulan, Tian Furong, McCully Mark, Berry {Catherine C. }, Baptista {Pedro Miguel Ribeiro Viana}, Tortiglione Claudia, and {de la Fuente} {Jesus M. } , Nano today, aug, Volume 10, Number 4, p.421–450, (2015) Abstract

RNAi has always captivated scientists due to its tremendous power to modulate the phenotype of living organisms. This natural and powerful biological mechanism can now be harnessed to downregulate specific gene expression in diseased cells, opening up endless opportunities. Since most of the conventional siRNA delivery methods are limited by a narrow therapeutic index and significant side and off-target effects, we are now in the dawn of a new age in gene therapy driven by nanotechnology vehicles for RNAi therapeutics. Here, we outlook the {"}do's and dont's{"} of the inorganic RNAi nanomaterials developed in the last 15 years and the different strategies employed are compared and scrutinized, offering important suggestions for the next 15. (C) 2015 Elsevier Ltd. All rights reserved.

Gold nanoparticle-siRNA mediated oncogene knockdown at RNA and protein level, with associated gene effects, Child, {Hannah Winifred}, Hernandez Yulan, Conde Joao, Mullin Margaret, Baptista Pedro, {Maria de la Fuente} Jesus, and Berry {Catherine Cecilia} , Nanomedicine, Volume 10, Number 16, p.2513–2525, (2015) Abstract

Aims: RNAi is a powerful tool for gene silencing that can be used to reduce undesirable overexpression of oncogenes as a novel form of cancer treatment. However, when using RNAi as a therapeutic tool there is potential for associated gene effects. This study aimed to utilize gold nanoparticles to deliver siRNA into HeLa cells. Results: Knockdown of the c-myc oncogene by RNAi, at the RNA, protein and cell proliferation level was achieved, while also identifying associated gene responses. Discussion: The gold nanoparticles used in this study present an excellent delivery platform for siRNA, but do note associated gene changes. Conclusion: The study highlights the need to more widely assess the cell physiological response to RNAi treatment, rather than focus on the immediate RNA levels.

RNAi-based glyconanoparticles trigger apoptotic pathways for in vitro and in vivo enhanced cancer-cell killing, Conde, João, Tian Furong, Hernandez Yulan, Bao Chenchen, Baptista {Pedro Miguel Ribeiro Viana}, Cui Daxiang, Stoeger Tobias, and {de la Fuente} {Jesus M. } , Nanoscale, Volume 7, Number 19, p.9083–9091, (2015) Abstract

Gold glyconanoparticles (GlycoNPs) are full of promise in areas like biomedicine, biotechnology and materials science due to their amazing physical, chemical and biological properties. Here, siRNA GlycoNPs (AuNP@PEG@Glucose@siRNA) in comparison with PEGylated GlycoNPs (AuNP@PEG@Glucose) were applied in vitro to a luciferase-CMT/167 adenocarcinoma cancer cell line and in vivo via intratracheal instillation directly into the lungs of B6 albino mice grafted with luciferase-CMT/167 adenocarcinoma cells. siRNA GlycoNPs but not PEGylated GlycoNPs induced the expression of pro-apoptotic proteins such as Fas/CD95 and caspases 3 and 9 in CMT/167 adenocarcinoma cells in a dose dependent manner, independent of the inflammatory response, evaluated by bronchoalveolar lavage cell counting. Moreover, in vivo pulmonary delivered siRNA GlycoNPs were capable of targeting c-Myc gene expression (a crucial regulator of cell proliferation and apoptosis) via in vivo RNAi in tumour tissue, leading to an similar to 80% reduction in tumour size without associated inflammation.

2013
Invivo tumor targeting via nanoparticle-mediated therapeutic siRNA coupled to inflammatory response in lung cancer mouse models, Conde, João, Tian Furong, Hernández Yulán, Bao Chenchen, Cui Daxiang, Janssen {Klaus Peter}, Ibarra Ricardo} {M., Baptista {Pedro V. }, Stoeger Tobias, and {de la Fuente} {Jesús M. } , Biomaterials, oct, Volume 34, Number 31, p.7744–7753, (2013) Abstract

Up to now, functionalized gold nanoparticles have been optimized as an effective intracellular invitro delivery vehicle for siRNAs to interfere with the expression of specific genes by selective targeting, and provide protection against nucleases. Few examples however of suchlike invivo applications have been described so far. In this study, we report the use of siRNA/RGD gold nanoparticles capable of targeting tumor cells in a lung cancer syngeneic orthotopic murine model. Therapeutic RGD-nanoparticle treatment resulted in successful targeting evident from significant c-myc oncogene down-regulation followed by tumor growth inhibition and prolonged survival of lung tumor bearing mice, possibly via αvβ3 integrin interaction. Our results suggest that RGD gold nanoparticles-mediated delivery of siRNA by intratracheal instillation in mice leads to successful suppression of tumor cell proliferation and respective tumor size reduction. These results reiterate the capability of functionalized gold nanoparticles for targeted delivery of siRNA to cancer cells towards effective silencing of the specific target oncogene. What is more, we demonstrate that the gold-nanoconjugates trigger a complex inflammatory and immune response that might promote the therapeutic effect of the RNAi to reduce tumor size with low doses of siRNA.

Designing gold nanoparticles for in vivo gene silencing as a new therapeutic tool, Conde, João, Ambrosone A., Hernandez Yulan, Marchesano V., Tian Furong, {Ricardo Ibarra} M., Baptista {Pedro Viana}, Tortiglione C., and {de la Fuente} {Jesus M. } , Human Gene Therapy, dec, Volume 24, Number 12, p.A24–A24, (2013) Abstract
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2012
Design of multifunctional gold nanoparticles for in vitro and in vivo gene silencing, Conde, João, Ambrosone Alfredo, Sanz Vanesa, Hernandez Yulan, Marchesano Valentina, Tian Furong, Child Hannah, Berry {Catherine C. }, Ibarra Ricardo} {M., Baptista {Pedro V. }, Tortiglione Claudia, and {de la Fuente} {Jesus M. } , ACS Nano, sep, Volume 6, Number 9, p.8316–8324, (2012) Abstract

Over the past decade, the capability of double-stranded RNAs to interfere with gene expression has driven new therapeutic approaches. Since small interfering RNA (siRNAs, 21 base pair double-stranded RNA) was shown to be able to elicit RNA interference (RNAi), efforts were directed toward the development of efficient delivery systems to preserve siRNA bioactivity throughout the delivery route, from the administration site to the target cell. Here we provide evidence of RNAi triggering, specifically silencing c-myc protooncogene, via the synthesis of a library of novel multifunctional gold nanoparticles (AuNPs). The efficiency of the AuNPs is demonstrated using a hierarchical approach including three biological systems of increasing complexity: in vitro cultured human cells, in vivo invertebrate (freshwater polyp, Hydra), and in vivo vertebrate (mouse) models. Our synthetic methodology involved fine-tuning of multiple structural and functional moieties. Selection of the most active functionalities was assisted step-by-step through functional testing that adopted this hierarchical strategy. Merging these chemical and biological approaches led to a safe, nonpathogenic, self-tracking, and universally valid nanocarrier that could be exploited for therapeutic RNAi.

Modification of plasmid DNA topology by histone-mimetic gold nanoparticles, Conde, João, Baptista {Pedro V. }, Hernández Yulan, Sanz Vanesa, and {de la Fuente} {Jesus M. } , Nanomedicine, nov, Volume 7, Number 11, p.1657–1666, (2012) Abstract

Aims: Our aim is to explore whether gold nanoparticles (AuNPs) functionalized with a carboxylated polyethylene glycol (PEG) and protamine (AuNP@PEG@Prot) can modulate - enhance or restrain - DNA condensation, altering DNA conformation and inducing structural changes. Understanding how these nanoconjugates modulate DNA structure, size and shape of DNA condensates, and enable control over the resulting 3D structures is of major biological and therapeutic importance. Materials & methods: Citrate-AuNPs were covered with a dense layer of a hetero-functional octa(ethylene glycol) (SH-EG(8)-COOH). Conjugation of protamine to the AuNP@PEG was achieved by taking advantage of the carboxylated surface previously generated on the surface of the NP and the remaining amino groups from the protamine, using carbodiimide and N-hydroxysulfosuccinimide coupling reactions. Results & conclusion: AuNP@PEG@Prot modulates the structure and topology of DNA, not only for condensation, but also for decondensation, via formation of higher quantities of dimers and multimers, when compared with AuNP@PEG and free protamine.

Multifunctional gold nanoparticles for gene silencing, Sanz, Vanesa, Conde João, Ambrosone Alfredo, Hernandez Yulan, Marchesasno Valentina, Estrada {Giovani G. }, Ibarra {Manuel R. }, Baptista {Pedro V. }, Tian Furong, Tortiglione Claudia, and {de la Fuente} {Jesus M. } , Abstracts Of Papers Of The American Chemical Society, mar, Volume 243, (2012) Abstract
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Effect of PEG biofunctional spacers and TAT peptide on dsRNA loading on gold nanoparticles, Sanz, Vanesa, Conde João, Hernández Yulán, Baptista {Pedro V. }, Ibarra {Manuel R. }, and {de la Fuente} {Jesús M. } , Journal Of Nanoparticle Research, jun, Volume 14, Number 6, (2012) Abstract

The surface chemistry of gold nanoparticles (AuNPs) plays a critical role in the self-assembly of thiolated molecules and in retaining the biological function of the conjugated biomolecules. According to the well-established gold-thiol interaction the undefined ionic species on citrate-reduced gold nanoparticle surface can be replaced with a self-assembled monolayer of certain thiolate derivatives and other biomolecules. Understanding the effect of such derivatives in the functionalization of several types of biomolecules, such as PEGs, peptides or nucleic acids, has become a significant challenge. Here, an approach to attach specific biomolecules to the AuNPs (∼14 nm) surface is presented together with a study of their effect in the functionalization with other specific derivatives. The effect of biofunctional spacers such as thiolated poly(ethylene glycol) (PEG) chains and a positive peptide, TAT, in dsRNA loading on AuNPs is reported. Based on the obtained data, we hypothesize that loading of oligonucleotides onto the AuNP surface may be controlled by ionic and weak interactions positioning the entry of the oligo through the PEG layer. We demonstrate that there is a synergistic effect of the TAT peptide and PEG chains with specific functional groups on the enhancement of dsRNA loading onto AuNPs.

2005
Colorimetric detection of eukaryotic gene expression with DNA-derivatized gold nanoparticles, Baptista, {Pedro Miguel Ribeiro Viana}, c}alo Dória Gon{\c, Henriques David, Pereira Eulália, and Franco Ricardo , Journal of Biotechnology, jan, Volume 119, Number 2, p.111–7, (2005) Abstract

Thiol-linked DNA-gold nanoparticles were used in a novel colorimetric method to detect the presence of specific mRNA from a total RNA extract of yeast cells. The method allowed detection of expression of the FSY1 gene that encodes a specific fructose/H+ symporter in Saccharomyces bayanus PYCC 4565. FSY1 is strongly expressed when the yeast is grown in fructose as the sole carbon source, while cells cultivated in glucose as the sole carbon source repress gene expression. The presence of FSY1 mRNA is detected based on color change of a sample containing total RNA extracted from the organism and gold nanoparticles derivatized with a 15-mer of complementary single stranded DNA upon addition of NaCl. If FSY1 mRNA is present, the solution remains pink, changing to blue-purple in the absence of FSY1 mRNA. Direct detection of specific expression was possible from only 0.3 microg of unamplified total RNA without any further enhancement. This novel method is inexpensive, very easy to perform as no amplification or signal enhancement steps are necessary and takes less than 15 min to develop after total RNA extraction. No temperature control is necessary and color change can be easily detected visually.