Publications

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2024
Bringing Hope to Improve Treatment in Pancreatic Ductal Adenocarcinoma: A New Tool for Molecular Profiling of KRAS Mutations in Tumor and Plasma Samples, Bravo, {Ana Catarina}, Morão Bárbara, Luz André, Dourado Rúben, Oliveira Beatriz, Guedes Ana, Moreira-Barbosa Catarina, Fidalgo Catarina, Mascarenhas-Lemos Luís, Costa-Santos {Maria Pia}, Maio Rui, Paulino Jorge, {Viana Baptista} Pedro, Fernandes {Alexandra R. }, and Cravo Marília , Cancers, oct, Volume 16, Number 20, (2024) Abstract

Background/Objectives: Pancreatic ductal adenocarcinoma (PDAC) incidence is rising, and prognosis remains poor due to late diagnosis and limited effective therapies. Currently, patients are treated based on TNM staging, without molecular tumor characterization. This study aimed to validate a technique that combines the amplification refractory mutation system (ARMS) with high-resolution melting analysis (HRMA) for detecting mutations in codon 12 of KRAS in tumor and plasma, and to assess its prognostic value. Methods: Prospective study including patients with newly diagnosed PDAC with tumor and plasma samples collected before treatment. Mutations in codon 12 of KRAS (G12D, G12V, G12C, and G12R) were detected using ARMS–HRMA and compared to Sanger sequencing (SS). Univariate and multivariate analyses were used to evaluate the prognostic significance of these mutations. Results: A total of 88 patients, 93% with ECOG-PS 0–1, 57% with resectable disease. ARMS–HRMA technique showed a higher sensitivity than SS, both in tumor and plasma (77% vs. 51%; 25 vs. 0%, respectively). The most frequent mutation was G12D (n = 32, 36%), followed by G12V (n = 22, 25%). On multivariate analysis, patients with G12D and/or G12C mutations, either in tumor or plasma, had lower PFS (HR 1.792, 95% CI 1.061–3.02

Breaking the mold: 3D cell cultures reshaping the future of cancer research, Cordeiro, Sandra, Oliveira {Beatriz B. }, Valente Ruben, Ferreira Daniela, Luz André, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Frontiers in Cell and Developmental Biology, Volume 12, (2024) Abstract

Despite extensive efforts to unravel tumor behavior and develop anticancer therapies, most treatments fail when advanced to clinical trials. The main challenge in cancer research has been the absence of predictive cancer models, accurately mimicking the tumoral processes and response to treatments. The tumor microenvironment (TME) shows several human-specific physical and chemical properties, which cannot be fully recapitulated by the conventional 2D cell cultures or the in vivo animal models. These limitations have driven the development of novel in vitro cancer models, that get one step closer to the typical features of in vivo systems while showing better species relevance. This review introduces the main considerations required for developing and exploiting tumor spheroids and organoids as cancer models. We also detailed their applications in drug screening and personalized medicine. Further, we show the transition of these models into novel microfluidic platforms, for improved control over physiological parameters and high-throughput screening. 3D culture models have provided key insights into tumor biology, more closely resembling the in vivo TME and tumor characteristics, while enabling the development of more reliable and precise anticancer therapies.

2022
Boron clusters (ferrabisdicarbollides) shaping the future as radiosensitizers for multimodal (chemo/radio/PBFR) therapy of glioblastoma, Nuez-Martínez, Miquel, Queralt-Martín María, Muñoz-Juan Amanda, Aguilella {Vicente M. }, Laromaine Anna, Teixidor Francesc, Viñas Clara, Pinto {Catarina G. }, Pinheiro Teresa, Guerreiro {Joana F. }, Mendes Filipa, Roma-Rodrigues Catarina, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Valic Srecko, and Marques Fernanda , Journal of Materials Chemistry B, dec, Volume 10, Number 47, p.9794–9815, (2022) Abstract

Glioblastoma multiforme (GBM) is the most common and fatal primary brain tumor, and is highly resistant to conventional radiotherapy and chemotherapy. Therefore, the development of multidrug resistance and tumor recurrence are frequent. Given the poor survival with the current treatments, new therapeutic strategies are urgently needed. Radiotherapy (RT) is a common cancer treatment modality for GBM. However, there is still a need to improve RT efficiency, while reducing the severe side effects. Radiosensitizers can enhance the killing effect on tumor cells with less side effects on healthy tissues. Herein, we present our pioneering study on the highly stable and amphiphilic metallacarboranes, ferrabis(dicarbollides) ([o-FESAN]− and [8,8′-I2-o-FESAN]−), as potential radiosensitizers for GBM radiotherapy. We propose radiation methodologies that utilize secondary radiation emissions from iodine and iron, using ferrabis(dicarbollides) as iodine/iron donors, aiming to achieve a greater therapeutic effect than that of a conventional radiotherapy. As a proof-of-concept, we show that using 2D and 3D models of U87 cells, the cellular viability and survival were reduced using this treatment approach. We also tested for the first time the proton boron fusion reaction (PBFR) with ferrabis(dicarbollides), taking advantage of their high boron (11B) content. The results from the cellular damage response obtained suggest that proton boron fusion radiation therapy, when combined with boron-rich compounds, is a promising modality to fight against resistant tumors. Although these results are encouraging, more developments are needed to further explore ferrabis(dicarbollides) as radiosensitizers towards a positive impact on the therapeutic strategies for GBM.

2021
Benchtop X-ray fluorescence imaging as a tool to study gold nanoparticle penetration in 3D cancer spheroids, Pedrosa, Pedro, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Guerra Mauro , RSC Advances, jul, Volume 11, Number 42, p.26344–26353, (2021) Abstract

The use of nanomaterials to improve medical diagnostics and therapeutics has been rapidly increasing. Among these materials are gold nanoparticles, which can be functionalized to target specific cells, acting as nanovectors for drug delivery, enhanced contrast agents as well as other targeted therapies. Au nanoparticles are very useful as they selectively accumulate in tumour sites due to the enhanced permeability-retention effect. There is however little information about the spatial distribution of the nanoparticles within tumours, which might hinder efficient therapies. In this study, X-ray fluorescence was used to investigate the diffusion of gold nanoparticles in cancer cell spheroids mimicking true tumour growth. Functionalization of the nanoparticles has the effect of allowing better diffusion into and out of the spheroid, while those nanoparticles that are only partially covered rapidly formed aggregates. This clustering led to size exclusion during transport within the tumour, changing its distribution profile while greatly increasing the nanoparticle concentration.

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.

2013
Bio-microfluidic platform for gold nanoprobe based DNA detection-application to Mycobacterium tuberculosis, Bernacka-Wójcik, Iwona, Lopes {Paulo A. }, Vaz {Ana Catarina}, Veigas {Bruno Miguel Ribeiro}, Wojcik {Pawel Jerzy}, Simões Pedro, Barata David, Fortunato {Elvira Maria Correia}, Baptista {Pedro Miguel Ribeiro Viana}, Águas {Hugo Manuel Brito}, and de Martins {Rodrigo Ferrão Paiva} , Biosensors & Bioelectronics, oct, Volume 48, p.87–93, (2013) Abstract

We have projected and fabricated a microfluidic platform for DNA sensing that makes use of an optical colorimetric detection method based on gold nanoparticles. The platform was fabricated using replica moulding technology in PDMS patterned by high-aspect-ratio SU-8 moulds. Biochips of various geometries were tested and evaluated in order to find out the most efficient architecture, and the rational for design, microfabrication and detection performance is presented. The best biochip configuration has been successfully applied to the DNA detection of Mycobacterium tuberculosis using only 3 mu l on DNA solution (i.e. 90 ng of target DNA), therefore a 20-fold reduction of reagents volume is obtained when compared with the actual state of the art.

1998
Bacterial contig map of the 21q11 region associated with Alzheimer's disease and abnormal myelopoiesis in Down syndrome, GROET, J., Ives {J. H. }, South {A. P. }, Baptista {P. R. }, Jones {T. A. }, Yaspo {M. L. }, Lehrach H., Potier {M. C. }, {Van Broeckhoven} C., and Nizetic D. , Genome Research, jan, Volume 8, Number 4, p.385–398, (1998) Abstract

We present a high-resolution bacterial contig map of 3.4 Mb of genomic DNA in human chromosome 21q11-q21, encompassing the region of elevated disomic homozygosity in Down Syndrome-associated abnormal myelopoiesis and leukemia, as well as the markers, which has shown a strong association with Alzheimer's Disease that has never been explained. The map contains 89 overlapping PACs, BACs, or cosmids in three contigs (850, 850, and 1500 kb) with two gaps (one of 140-210 kb and the second < 5 kb). To date, eight transcribed sequences derived by cDNA selection, exon trapping, and/or global EST sequencing have been positioned onto the map, and the only two genes so far mapped to this cytogenetic region, STCH and RIP140 have been precisely localized. This work converts a further 10% of chromosome 21q into a high-resolution bacterial contig map, which will be the physical basis for the long-range sequencing of this region. The map will also enable positional derivation of new transcribed sequences, as well as new polymorphic probes, that will help in elucidation of the role the genes in this region may play in abnormal myelopoiesis and leukemia associated with trisomy 21 and Alzheimer's Disease.