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

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

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

Optimization of Antiproliferative Properties of Triimine Copper(II) Complexes, Choroba, K., Zowislok B., Kula S., Machura B., Maron A. M., Erfurt K., Cordeiro S., Baptista P. V., and Fernandes {Alexandra R. } , Journal Of Medicinal Chemistry, nov, Volume 67, Number 21, p.19475–19502, (2024) Abstract

Cu(II) complexes with 2,2′:6′,2″-terpyridines (terpy) and 2,6-bis(thiazol-2-yl)pyridines (dtpy) with 1- or 2-naphtyl and methoxy-naphtyl were synthesized to elucidate the impact of the triimine core, naphtyl linking mode, and presence of methoxy groups on the antiproliferative activity of [CuCl2(Ln)]. Their antiproliferative effect was analyzed in ovarian (A2780) and colorectal (HCT116) carcinomas and colorectal carcinoma resistant to doxorubicin (HCT116-DoxR) cell lines and in normal human fibroblasts. Among all complexes, the 1- and 2-naphtyl substituted terpy Cu(II) complexes (Cu1a and Cu1b) showed the strongest cytotoxicity, namely, in HCT116-DoxR 2Dcells and were also capable of inducing the loss of cell viability in 3D HCT116-DoxR spheroids. Their intracellular localization, capability to increase reactive oxygen species (ROS), and interaction with DNA (nonintercalative mode) trigger oxidative DNA cleavage leading to cell death by apoptosis and autophagy. Cu1a and Cu1b do not show in vivo toxicity in a chicken embryo and can interact with bovine serum albumin (BSA).

Optimization of Antiproliferative Properties of Triimine Copper(II) Complexes, Choroba, Katarzyna, Zowiślok Bartosz, Kula Sławomir, Machura Barbara, Maroń {Anna M. }, Erfurt Karol, Marques Cristiana, Cordeiro Sandra, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Journal Of Medicinal Chemistry, nov, (2024) Abstract

Cu(II) complexes with 2,2':6',2″-terpyridines (terpy) and 2,6-bis(thiazol-2-yl)pyridines (dtpy) with 1- or 2-naphtyl and methoxy-naphtyl were synthesized to elucidate the impact of the triimine core, naphtyl linking mode, and presence of methoxy groups on the antiproliferative activity of [CuCl 2(L n )]. Their antiproliferative effect was analyzed in ovarian (A2780) and colorectal (HCT116) carcinomas and colorectal carcinoma resistant to doxorubicin (HCT116-DoxR) cell lines and in normal human fibroblasts. Among all complexes, the 1- and 2-naphtyl substituted terpy Cu(II) complexes ( Cu1a and Cu1b) showed the strongest cytotoxicity, namely, in HCT116-DoxR 2Dcells and were also capable of inducing the loss of cell viability in 3D HCT116-DoxR spheroids. Their intracellular localization, capability to increase reactive oxygen species (ROS), and interaction with DNA (nonintercalative mode) trigger oxidative DNA cleavage leading to cell death by apoptosis and autophagy. Cu1a and Cu1b do not show in vivo toxicity in a chicken embryo and can interact with bovine serum albumin (BSA).

Evaluation of miR-155 silencing using a molecular beacon in human lung adenocarcinoma cell line, Alexandre, Daniela, Fernandes {Alexandra R. }, Baptista {Pedro V. }, and Cruz Carla , Talanta, jul, Volume 274, (2024) Abstract

Lung cancer (LC) is a leading cause of global cancer-related deaths, highlighting the development of innovative methods for biomarker detection improving the early diagnostics. microRNAs (miRs) alterations are known to be involved in the initiation and progression of human cancers and can act as biomarkers for diagnostics and treatment. Herein, we develop the application of molecular beacon (MB) technology to monitor miR-155-3p expression in human lung adenocarcinoma A549 cells without complementary DNA synthesis, amplification, or expensive reagents. Furthermore, we produced gold nanoparticles (AuNPs) for delivering antisense oligonucleotides into A549 cells to reduce miR-155-3p expression, which was subsequently detectable using the MB. The MB was designed and structural characterized by Förster Resonance Energy Transfer (FRET)-melting, Circular Dichroism (CD), Nuclear magnetic resonance (NMR), and fluorometric experiments, and then the hybridization conditions were optimized for an in vitro approach involving the detection of miR-155-3p in total RNA extracted from A549 cell line. The expression profile of miR-155-3p was obtained by RT-qPCR. The results demonstrated that MB was properly designed and showed efficacy in targeting miR-155-3p. Furthermore, a limit of detection down to nanomolar concentration was achieved and the specificity of the biosensor was proved. Moreover, the self-assembly of ASOs with AuNPs exhibited exceptional target specificity, effectively silencing miR-155-3p. Notably, compared to lipid-based transfection agent, AuNPs displayed superior silencing efficiency. We highlighted the ability of MB to detect changes in the target gene expression after gene silencing. Overall, this innovative approach represents a promising tool for detecting various biomarkers at the same time, with potential applications in clinical settings.

Exploiting Co(III)-Cyclopentadienyl Complexes To Develop Anticancer Agents, {Franco Machado}, João, Cordeiro Sandra, Duarte {Joana N. }, Costa {Paulo J. }, Mendes {Paulo J. }, Garcia {Maria Helena}, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Morais {Tânia S. } , Inorganic Chemistry, apr, Volume 63, Number 13, p.5783–5804, (2024) Abstract

In recent years, organometallic complexes have attracted much attention as anticancer therapeutics aiming at overcoming the limitations of platinum drugs that are currently marketed. Still, the development of half-sandwich organometallic cobalt complexes remains scarcely explored. Four new cobalt(III)-cyclopentadienyl complexes containing N,N-heteroaromatic bidentate, and phosphane ligands were synthesized and fully characterized by elemental analysis, spectroscopic techniques, and DFT methods. The cytotoxicity of all complexes was determined in vitro by the MTS assay in colorectal (HCT116), ovarian (A2780), and breast (MDA-MB-231 and MCF-7) human cancer cell lines and in a healthy human cell line (fibroblasts). The complexes showed high cytotoxicity in cancer cell lines, mostly due to ROS production, apoptosis, autophagy induction, and disruption of the mitochondrial membrane. Also, these complexes were shown to be nontoxic in vivo in an ex ovo chick embryo yolk sac membrane (YSM) assay.

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.

Copper(II) Complexes with 2,2′:6′,2″-Terpyridine Derivatives Displaying Dimeric Dichloro−μ-Bridged Crystal Structure: Biological Activities from 2D and 3D Tumor Spheroids to In Vivo Models, Choroba, Katarzyna, Machura Barbara, Erfurt Karol, Casimiro {Ana Rita}, Cordeiro Sandra, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Journal Of Medicinal Chemistry, Volume 67, Number 7, p.5813–5836, (2024) Abstract

Eight 2,2′:6′,2″-terpyridines, substituted at the 4′-position with aromatic groups featuring variations in π-conjugation, ring size, heteroatoms, and methoxy groups, were employed to enhance the antiproliferative potential of [Cu2Cl2(R-terpy)2](PF6)2. Assessing the cytotoxicity in A2780 (ovarian carcinoma), HCT116 (colorectal carcinoma), and HCT116DoxR (colorectal carcinoma resistant to doxorubicin) and normal primary fibroblasts revealed that Cu(II) complexes with 4-quinolinyl, 4-methoxy-1-naphthyl, 2-furanyl, and 2-pyridynyl substituents showed superior therapeutic potential in HCT116DoxR cells with significantly reduced cytotoxicity in normal fibroblasts (42-129× lower). Besides their cytotoxicity, the Cu(II) complexes are able to increase intracellular ROS and interfere with cell cycle progression, leading to cell death by apoptosis and autophagy. Importantly, they demonstrated antimetastatic and antiangiogenic properties without in vivo toxicity. In accordance with their nuclear accumulation, the Cu(II) complexes are able to cleave pDNA and interact with bovine serum albumin, which is a good indication of their ability for internalization and transport toward tumor cells.

Detecting mir-155-3p through a Molecular Beacon Bead-Based Assay, Moreira, David, Alexandre Daniela, Miranda André, c}o Pedro Louren{\c, Baptista {Pedro V. }, Tomaz Cândida, Lu Yi, and Cruz Carla , Molecules, Volume 29, Number 13, (2024) Abstract

Lung cancer (LC) is recognized as one of the most prevalent and lethal cancers worldwide, underscoring an urgent need for innovative diagnostic and therapeutic approaches. MicroRNAs (miRNAs) have emerged as promising biomarkers for several diseases and their progression, such as LC. However, traditional methods for detecting and quantifying miRNAs, such as PCR, are time-consuming and expensive. Herein, we used a molecular beacon (MB) bead-based assay immobilized in a microfluidic device to detect miR-155-3p, which is frequently overexpressed in LC. The assay relies on the fluorescence enhancement of the MB upon binding to the target miRNA via Watson and Crick complementarity, resulting in a conformational change from a stem–loop to a linear structure, thereby bringing apart the fluorophores at each end. This assay was performed on a microfluidic platform enabling rapid and straightforward target detection. We successfully detected miR-155-3p in a saline solution, obtaining a limit of detection (LOD) of 42 nM. Furthermore, we evaluated the method’s performance in more complex biological samples, including A549 cells’ total RNA and peripheral blood mononuclear cells (PBMCs) spiked with the target miRNA. We achieved satisfactory recovery rates, especially in A549 cells’ total RNA.

Discovery of Novel Fluorescent Azaindoles with Cytotoxic Action in A2780 Ovarian Carcinoma Cells, Cunha, {José C. }, Roma-Rodrigues Catarina, Ferreira {Joana R. M. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Guieu S., and Marques Manuel {M. B. } , Chemmedchem, Volume 19, Number 20, (2024) Abstract

Azaindole scaffold is a privileged structure in medicinal chemistry and some derivatives have demonstrated to be potential anticancer drugs. Herein, a set of novel azaindoles, comprising the four regioisomers, bearing a morpholine (azaindoles 3a-d) and N-methyl-N-benzylamine (azaindoles 4a-d) groups were prepared. Among these compounds, azaindoles 4 exhibited higher cytotoxicity against the ovarian cancer cell line A2780 and normal dermal fibroblasts compared to azaindoles 3. Furthermore, azaindoles 4b and 4c promoted a delay in the cell cycle of the cancer cell line, inspiring an investigation into the intracellular localization of these derivatives.

Effect of mono- and dinuclear thiosemicarbazone platinacycles in the proliferation of a colorectal carcinoma cell line, Reigosa-Chamorro, Francisco, Cordeiro Sandra, Pereira Teresa} {M., Filipe Beatriz, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Vila {José M. } , Dalton Transactions, (2024) Abstract

Herein, we describe the synthesis and characterization of a series of thiosemicarbazone platinacycles. Their activity towards HCT116 and A2780 cancer cell lines as well as normal fibroblasts was explored and conclusions about the influence of their structures were drawn based on the results. Ligands L1-3, tetranuclear compounds [Pt(L1-3)]4, [Pt(L1-3)(PPh3)], and [Pt(L1-L3)2{Ph2P(CH2)4PPh2}], and phosphine derivatives, were deemed unpromising owing to their lack of activity. However, mono-coordinated diphosphine complexes [Pt(L1-L3)(Ph2PCH2PPh2-P)] showed high selectivity and low IC50 values, and their antiproliferative activity was further studied. The three studied derivatives 3a, 3b and 3c showed a fast internalization of HCT116 colorectal cancer cells with similar IC50 values, which induced a depolarization of mitochondrial membrane potential, with the subsequent triggering of apoptosis and autophagy in the case of 3c. In the case of compounds 3a and 3b, cell death mechanisms (extrinsic and intrinsic apoptosis, respectively) were triggered via the induction of reactive oxygen species (ROS). The three compounds were not toxic to a chicken embryo in vivo (after 48 h), and, importantly, showed an anti-angiogenic potential after exposure to the IC50 of compounds 3a, 3b and 3c.

Optimization of Antiproliferative Properties of Triimine Copper(II) Complexes, Choroba, Katarzyna, Zowiślok Bartosz, Kula Sławomir, Machura Barbara, Maroń {Anna M. }, Erfurt Karol, Marques Cristiana, Cordeiro Sandra, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Journal Of Medicinal Chemistry, Volume 67, Number 21, p.19475–19502, (2024) Abstract

Cu(II) complexes with 2,2′:6′,2″-terpyridines (terpy) and 2,6-bis(thiazol-2-yl)pyridines (dtpy) with 1- or 2-naphtyl and methoxy-naphtyl were synthesized to elucidate the impact of the triimine core, naphtyl linking mode, and presence of methoxy groups on the antiproliferative activity of [CuCl2(Ln)]. Their antiproliferative effect was analyzed in ovarian (A2780) and colorectal (HCT116) carcinomas and colorectal carcinoma resistant to doxorubicin (HCT116-DoxR) cell lines and in normal human fibroblasts. Among all complexes, the 1- and 2-naphtyl substituted terpy Cu(II) complexes (Cu1a and Cu1b) showed the strongest cytotoxicity, namely, in HCT116-DoxR 2Dcells and were also capable of inducing the loss of cell viability in 3D HCT116-DoxR spheroids. Their intracellular localization, capability to increase reactive oxygen species (ROS), and interaction with DNA (nonintercalative mode) trigger oxidative DNA cleavage leading to cell death by apoptosis and autophagy. Cu1a and Cu1b do not show in vivo toxicity in a chicken embryo and can interact with bovine serum albumin (BSA).

2023
Parylene C as a Multipurpose Material for Electronics and Microfluidics, Coelho, {Beatriz J. }, Pinto {Joana V. }, Martins Jorge, Rovisco Ana, Barquinha Pedro, Fortunato Elvira, Baptista {Pedro V. }, Martins Rodrigo, and Igreja Rui , Polymers, may, Volume 15, Number 10, (2023) Abstract

Poly(p-xylylene) derivatives, widely known as Parylenes, have been considerably adopted by the scientific community for several applications, ranging from simple passive coatings to active device components. Here, we explore the thermal, structural, and electrical properties of Parylene C, and further present a variety of electronic devices featuring this polymer: transistors, capacitors, and digital microfluidic (DMF) devices. We evaluate transistors produced with Parylene C as a dielectric, substrate, and encapsulation layer, either semitransparent or fully transparent. Such transistors exhibit steep transfer curves and subthreshold slopes of 0.26 V/dec, negligible gate leak currents, and fair mobilities. Furthermore, we characterize MIM (metal–insulator–metal) structures with Parylene C as a dielectric and demonstrate the functionality of the polymer deposited in single and double layers under temperature and AC signal stimuli, mimicking the DMF stimuli. Applying temperature generally leads to a decrease in the capacitance of the dielectric layer, whereas applying an AC signal leads to an increase in said capacitance for double-layered Parylene C only. By applying the two stimuli, the capacitance seems to suffer from a balanced influence of both the separated stimuli. Lastly, we demonstrate that DMF devices with double-layered Parylene C allow for faster droplet motion and enable long nucleic acid amplification reactions.

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

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

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

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

Half-sandwich Ru(II) N-heterocyclic carbene complexes in anticancer drug design, {Lenis Rojas}, {Oscar A. }, Cordeiro Sandra, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Journal of Inorganic Biochemistry, aug, Volume 245, (2023) Abstract

The ruthenium arene fragment is a rich source for the design of anticancer drugs; in this design, the co-ligand is a critical factor for obtaining effective anticancer complexes. In comparison with other types of ligands, N-heterocyclic carbenes (NHCs) have been less explored, despite the versatility in structural modifications and the marked stabilization of metal ions, being these characteristics important for the design of metal drugs. However, notable advances have been made in the development of NHC Ruthenium arene as anticancer agents. These advances include high antitumor activities, proven both in in vitro and in in vivo models and, in some cases, with marked selectivity against tumorigenic cells. The versatility of the structure has played a fundamental role, since they have allowed a selective interaction with their molecular targets through, for example, bio-conjugation with known anticancer molecules. For this reason, the structure-activity relationship of the imidazole, benzimidazole, and abnormal NHC ruthenium (II) η6-arene complexes have been studied. Taking into account this study, several synthetic aspects are provided to contribute to the next generations of this kind of complexes. Moreover, in recent years nanotechnology has provided innovative nanomedicines, where half-sandwich Ruthenium(II) complexes are paving their way. In this review, the recent developments in nanomaterials functionalized with Ruthenium complexes for targeted drug delivery to tumors will also be highlighted.

Combining the amplification refractory mutation system and high-resolution melting analysis for KRAS mutation detection in clinical samples, Oliveira, {Beatriz B. }, Costa Beatriz, Morão Bárbara, Faias Sandra, Veigas Bruno, Pereira {Lucília Pebre}, Albuquerque Cristina, Maio Rui, Cravo Marília, Fernandes {Alexandra R. }, and Baptista {Pedro Viana} , Analytical and Bioanalytical Chemistry, Volume 415, Number 14, p.2849–2863, (2023) Abstract

The success of personalized medicine depends on the discovery of biomarkers that allow oncologists to identify patients that will benefit from a particular targeted drug. Molecular tests are mostly performed using tumor samples, which may not be representative of the tumor’s temporal and spatial heterogeneity. Liquid biopsies, and particularly the analysis of circulating tumor DNA, are emerging as an interesting means for diagnosis, prognosis, and predictive biomarker discovery. In this study, the amplification refractory mutation system (ARMS) coupled with high-resolution melting analysis (HRMA) was developed for detecting two of the most relevant KRAS mutations in codon 12. After optimization with commercial cancer cell lines, KRAS mutation screening was validated in tumor and plasma samples collected from patients with pancreatic ductal adenocarcinoma (PDAC), and the results were compared to those obtained by Sanger sequencing (SS) and droplet digital polymerase chain reaction (ddPCR). The developed ARMS-HRMA methodology stands out for its simplicity and reduced time to result when compared to both SS and ddPCR but showing high sensitivity and specificity for the detection of mutations in tumor and plasma samples. In fact, ARMS-HRMA scored 3 more mutations compared to SS (tumor samples T6, T7, and T12) and one more compared to ddPCR (tumor sample T7) in DNA extracted from tumors. For ctDNA from plasma samples, insufficient genetic material prevented the screening of all samples. Still, ARMS-HRMA allowed for scoring more mutations in comparison to SS and 1 more mutation in comparison to ddPCR (plasma sample P7). We propose that ARMS-HRMA might be used as a sensitive, specific, and simple method for the screening of low-level mutations in liquid biopsies, suitable for improving diagnosis and prognosis schemes. Graphical Abstract: [Figure not available: see fulltext.]

Doxorubicin-sensitive and -resistant colorectal cancer spheroid models: assessing tumor microenvironment features for therapeutic modulation, Valente, Ruben, Cordeiro Sandra, Luz André, Rodrigues {Catarina Roma}, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Frontiers in Cell and Developmental Biology, Volume 11, (2023) Abstract

Introduction: The research on tumor microenvironment (TME) has recently been gaining attention due to its important role in tumor growth, progression, and response to therapy. Because of this, the development of three-dimensional cancer models that mimic the interactions in the TME and the tumor structure and complexity is of great relevance to cancer research and drug development. Methods: This study aimed to characterize colorectal cancer spheroids overtime and assess how the susceptibility or resistance to doxorubicin (Dox) or the inclusion of fibroblasts in heterotypic spheroids influence and modulate their secretory activity, namely the release of extracellular vesicles (EVs), and the response to Dox-mediated chemotherapy. Different characteristics were assessed over time, namely spheroid growth, viability, presence of hypoxia, expression of hypoxia and inflammation-associated genes and proteins. Due to the importance of EVs in biomarker discovery with impact on early diagnostics, prognostics and response to treatment, proteomic profiling of the EVs released by the different 3D spheroid models was also assessed. Response to treatment was also monitored by assessing Dox internalization and its effects on the different 3D spheroid structures and on the cell viability. Results and Discussion: The results show that distinct features are affected by both Dox resistance and the presence of fibroblasts. Fibroblasts can stabilize spheroid models, through the modulation of their growth, viability, hypoxia and inflammation levels, as well as the expressions of its associated transcripts/proteins, and promotes alterations in the protein profile exhibit by EVs. Summarily, fibroblasts can increase cell-cell and cell-extracellular matrix interactions, making the heterotypic spheroids a great model to study TME and understand TME role in chemotherapies resistance. Dox resistance induction is shown to influence the internalization of Dox, especially in homotypic spheroids, and it is also shown to influence cell viability and consequently the chemoresistance of those spheroids when exposed to Dox. Taken together these results highlight the importance of finding and characterizing different 3D models resembling more closely the in vivo interactions of tumors with their microenvironment as well as modulating drug resistance.

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

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

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

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

Digital Microfluidics-Powered Real-Time Monitoring of Isothermal DNA Amplification of Cancer Biomarker, Coelho, {Beatriz Jorge}, Veigas Bruno, Bettencourt Luís, Águas Hugo, Fortunato Elvira, Martins Rodrigo, Baptista {Pedro V. }, and Igreja Rui , Biosensors, mar, Volume 12, Number 4, (2022) Abstract

We introduce a digital microfluidics (DMF) platform specifically designed to perform a loop-mediated isothermal amplification (LAMP) of DNA and applied it to a real-time amplification to monitor a cancer biomarker, c-Myc (associated to 40% of all human tumors), using fluorescence microscopy. We demonstrate the full manipulation of the sample and reagents on the DMF platform, resulting in the successful amplification of 90 pg of the target DNA (0.5 ng/µL) in less than one hour. Furthermore, we test the efficiency of an innovative mixing strategy in DMF by employing two mixing methodologies onto the DMF droplets—low frequency AC (alternating current) actuation as well as back-and-forth droplet motion—which allows for improved fluorescence readouts. Fluo-rophore bleaching effects are minimized through on-chip sample partitioning by DMF processes and sequential droplet irradiation. Finally, LAMP reactions require only 2 µL volume droplets, which represents a 10-fold volume reduction in comparison to benchtop LAMP.

Endogenous Fluorescent Proteins in the Mucus of an Intertidal Polychaeta: Clues for Biotechnology, Rodrigo, {Ana P. }, Lopes {Ana Catarina}, Pereira Ricardo, Anjo {Sandra I. }, Manadas Bruno, Grosso {Ana R. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Costa {Pedro M. } , Marine Drugs, mar, Volume 20, Number 4, (2022) Abstract

The vast ocean holds many unexplored organisms with unique adaptive features that enable them to thrive in their environment. The secretion of fluorescent proteins is one of them, with reports on the presence of such compounds in marine annelids being scarce. The intertidal Eulalia sp. is an example. The worm secretes copious amounts of mucus, that when purified and concentrated extracts, yield strong fluorescence under UV light. Emission has two main maxima, at 400 nm and at 500 nm, with the latter responsible for the blue–greenish fluorescence. Combining proteomics and transcriptomics techniques, we identified ubiquitin, peroxiredoxin, and 14-3-3 protein as key elements in the mucus. Fluorescence was found to be mainly modulated by redox status and pH, being consistently upheld in extracts prepared in Tris-HCl buffer with reducing agent at pH 7 and excited at 330 nm. One of the proteins associated with the fluorescent signal was localized in secretory cells in the pharynx. The results indicate that the secretion of fluorescent proteinaceous complexes can be an important defense against UV for this dweller. Additionally, the internalization of fluorescent complexes by ovarian cancer cells and modulation of fluorescence of redox status bears important considerations for biotechnological application of mucus components as markers.

Molecular Beacon for Detection miRNA-21 as a Biomarker of Lung Cancer, Alexandre, Daniela, Teixeira Bernardo, Rico André, Valente Salete, Craveiro Ana, Baptista {Pedro V. }, and Cruz Carla , International Journal of Molecular Sciences, mar, Volume 23, Number 6, (2022) Abstract

Lung cancer (LC) is the leading cause of cancer-related death worldwide. Although the diagnosis and treatment of non-small cell lung cancer (NSCLC), which accounts for approximately 80% of LC cases, have greatly improved in the past decade, there is still an urgent need to find more sensitive and specific screening methods. Recently, new molecular biomarkers are emerging as potential non-invasive diagnostic agents to screen NSCLC, including multiple microRNAs (miRNAs) that show an unusual expression profile. Moreover, peripheral blood mononuclear cells’ (PBMCs) miRNA profile could be linked with NSCLC and used for diagnosis. We developed a molecular beacon (MB)-based miRNA detection strategy for NSCLC. Following PBMCs isolation and screening of the expression profile of a panel of miRNA by RT-qPCR, we designed a MB targeting of up-regulated miR-21-5p. This MB 21-5p was characterized by FRET-melting, CD, NMR and native PAGE, allowing the optimization of an in-situ approach involving miR-21-5p detection in PBMCs via MB. Data show the developed MB approach potential for miR-21-5p detection in PBMCs from clinical samples towards NSCLC.

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

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

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

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

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