RESEARCH, TEACHING, or OTHER INTERESTS
Oncology
Scopus Publications
- Re-Thinking Pharmacokinetics in Ovarian Cancer: What Do Organoids Add?
Ana Emanuela Cisne de Lima, Mariana Nunes, Cristina P. R. Xavier, Sara Ricardo
International Journal of Molecular Sciences, 2026
Ovarian cancer (OC) remains one of the leading causes of gynecologic cancer mortality, largely due to late diagnosis, frequent relapse, and the emergence of chemoresistance. An important but often-overlooked contributor to treatment failure is the heterogeneous penetration of anticancer drugs within tumors. Structural and biochemical barriers—including abnormal vasculature, elevated interstitial pressure, dense extracellular matrix, drug efflux transporters, and malignant ascites—generate steep intratumoral concentration gradients that conventional preclinical models fail to capture. As a result, systemic pharmacokinetic measurements frequently provide limited insight into tumor-level drug exposure. Patient-derived organoids (PDOs) have emerged as physiologically relevant 3D models that preserve the genetic, architectural, and functional characteristics of the original tumor. These systems enable controlled investigation of pharmacokinetic and pharmacodynamic processes, including drug penetration, metabolism, retention, and exposure–response relationships. Adding cell-free malignant ascites supernatant enhances PDOs’ ability to mimic the metastatic peritoneal microenvironment of OC. This review discusses recent advances in PDO technologies and examines how PDO-derived data can inform intratumoral pharmacokinetics and dosing strategies using physiologically based pharmacokinetic modeling and in vitro–in vivo extrapolation. Emerging hybrid platforms, including organoid-on-chip systems, vascularized co-cultures, and multi-omics integration, are crucial to improve translational prediction and support precision oncology. - Paclitaxel resistance-associated metabolic events in ovarian cancer cells
Filipa Amaro, Mariana Nunes, Paula Guedes de Pinho, Sara Ricardo, Joana Pinto
Metabolomics, 2025 - Galanthamine Fails to Reverse P-gp-Mediated Paclitaxel Resistance in Ovarian Cancer Cell Lines
Nélia Fonseca, Mariana Nunes, Patrícia M. A. Silva, Hassan Bousbaa, Sara Ricardo
Biomedicines, 2025
Background: Ovarian cancer has the poorest prognosis of all gynecological malignancies, largely due to its chemoresistance, which poses significant treatment challenges. In this context, drug repurposing emerges as an innovative strategy that employs non-cancer treatments to interact with various signaling pathways, enhancing chemotherapy efficacy while minimizing toxicity. This study investigated the cytotoxic effects of galanthamine, currently used as an Alzheimer’s disease, as a potential treatment for high-grade serous carcinoma, both individually and in combination with paclitaxel. Methods: The Presto Blue assay, viability marker assessments, immunocytochemical analysis of apoptosis, and a cumulative assay were employed to evaluate the functionality of P-glycoprotein. Results: The results indicated that galanthamine did not demonstrate cytotoxic or synergistic effects in either high-grade serous carcinoma cell line tested, suggesting that it is not a viable strategy for overcoming paclitaxel resistance in this context. The immunocytochemistry analysis indicated that galanthamine does not affect the expression of proteins related to cell viability and proliferation and is not associated with chemoresistance. Additionally, functional assays showed that galanthamine treatment did not affect its drug efflux function at the cellular level. Conclusions: Overall, the results indicate that galanthamine is unsuitable for reversing paclitaxel resistance despite some literature suggesting its potential interaction with P-glycoprotein. - Ivermectin Strengthens Paclitaxel Effectiveness in High-Grade Serous Carcinoma in 3D Cell Cultures
Mariana Nunes, Sara Ricardo
Pharmaceuticals, 2025
Background: Chemoresistance is a major obstacle in high-grade serous carcinoma (HGSC) treatment. Although many patients initially respond to chemotherapy, the majority of them relapse due to Carboplatin and Paclitaxel resistance. Drug repurposing has surfaced as a potentially effective strategy that works synergically with standard chemotherapy to bypass chemoresistance. In a prior study, using 2D cultures and two HGSC chemoresistant cell lines, it was demonstrated that combining Carboplatin or Paclitaxel with Pitavastatin or Ivermectin resulted in the most notable synergy. Acknowledging that 2D culture systems are limited in reflecting the tumor architecture, 3D cultures were generated to provide insights on treatment efficacy tests in more complex models. Objectives: We aimed to investigate whether combining Carboplatin or Paclitaxel with Pitavastatin or Ivermectin offers therapeutic benefits in a Cultrex-based 3D model. Methods: Here, the cytotoxicity of Carboplatin and Paclitaxel, both alone and in combination with Pitavastatin or Ivermectin, were analyzed on two chemoresistant tumor cell lines, OVCAR8 and OVCAR8 PTX R C, in 3D cultures. Cellular viability was assessed using CellTiter-Glo® Luminescent assays. Also, it explored synergistic interactions using zero interaction potency, Loewe, Bliss independence, and High-single agent reference models. Results: Our research indicates combining chemotherapeutic drugs with Pitavastatin or Ivermectin yields significantly more cytotoxic effects than chemotherapy alone. For all the combinations tested, at least one model indicated an additive effect; however, only the combination of Paclitaxel and Ivermectin consistently demonstrated an additive effect across all chemoresistant cell lines cultured in 3D models, as well as in all four synergy reference models used to assess drug interactions. Conclusions: Combining Paclitaxel with Ivermectin has the highest cytotoxic and the strongest additive effect for both chemoresistant cell lines compared to Paclitaxel alone. - Metformin Impairs Linsitinib Anti-Tumor Effect on Ovarian Cancer Cell Lines
Diana Luísa Almeida-Nunes, João P. N. Silva, Mariana Nunes, Patrícia M. A. Silva, Ricardo Silvestre, et al.
International Journal of Molecular Sciences, 2024
Ovarian cancer (OC) remains one of the leading causes of cancer-related mortality among women. Targeting the insulin-like growth factor 1 (IGF-1) signaling pathway has emerged as a promising therapeutic strategy. Linsitinib, an IGF-1 receptor (IGF-1R) inhibitor, has shown potential in disrupting this pathway. Additionally, metformin, commonly used in the treatment of type 2 diabetes, has been studied for its anti-cancer properties due to its ability to inhibit metabolic pathways that intersect with IGF-1 signaling, making it a candidate for combination therapy in cancer treatments. This study explores the anti-cancer effects of linsitinib and metformin on OVCAR3 cells by the suppression of the IGF-1 signaling pathway by siRNA-mediated IGF-1 gene silencing. The goal is to evaluate their efficacy as therapeutic agents and to emphasize the critical role of this pathway in OC cell proliferation. Cellular viability was evaluated by resazurin-based assay, and apoptosis was assessed by flux cytometry. The results of this study indicate that the combination of linsitinib and metformin exhibits an antagonistic effect (obtained by SynergyFinder 2.0 Software), reducing their anti-neoplastic efficacy in OC cell lines. Statistical analyses were performed using ordinary one-way or two-way ANOVA, followed by Tukey’s or Šídák’s multiple comparison tests. While linsitinib shows promise as a therapeutic option for OC, further research is needed to identify agents that could synergize with it to enhance its therapeutic efficacy, like the combination with standard chemotherapy in OC (carboplatin and paclitaxel). - Ovarian cancer ascites proteomic profile reflects metabolic changes during disease progression
Diana Luísa Almeida-Nunes, Mariana Nunes, Hugo Osório, Verónica Ferreira, Cláudia Lobo, et al.
Biochemistry and Biophysics Reports, 2024 - Deciphering the Molecular Mechanisms behind Drug Resistance in Ovarian Cancer to Unlock Efficient Treatment Options
Mariana Nunes, Carla Bartosch, Miguel Henriques Abreu, Alan Richardson, Raquel Almeida, et al.
Cells, 2024
Ovarian cancer is a highly lethal form of gynecological cancer. This disease often goes undetected until advanced stages, resulting in high morbidity and mortality rates. Unfortunately, many patients experience relapse and succumb to the disease due to the emergence of drug resistance that significantly limits the effectiveness of currently available oncological treatments. Here, we discuss the molecular mechanisms responsible for resistance to carboplatin, paclitaxel, polyadenosine diphosphate ribose polymerase inhibitors, and bevacizumab in ovarian cancer. We present a detailed analysis of the most extensively investigated resistance mechanisms, including drug inactivation, drug target alterations, enhanced drug efflux pumps, increased DNA damage repair capacity, and reduced drug absorption/accumulation. The in-depth understanding of the molecular mechanisms associated with drug resistance is crucial to unveil new biomarkers capable of predicting and monitoring the kinetics during disease progression and discovering new therapeutic targets. - Cell Microarray: An Approach to Evaluate Drug-Induced Alterations in Protein Expression
Mariana Nunes, Diana Nunes, Sara Ricardo
Advancements in Cancer Research, 2023 - The Antineoplastic Effect of Carboplatin Is Potentiated by Combination with Pitavastatin or Metformin in a Chemoresistant High-Grade Serous Carcinoma Cell Line
Mariana Nunes, Diana Duarte, Nuno Vale, Sara Ricardo
International Journal of Molecular Sciences, 2023
The combination of Carboplatin with Paclitaxel is the mainstay treatment for high-grade serous carcinoma; however, many patients with advanced disease undergo relapse due to chemoresistance. Drug repurposing coupled with a combination of two or more compounds with independent mechanisms of action has the potential to increase the success rate of the antineoplastic treatment. The purpose of this study was to explore whether the combination of Carboplatin with repurposed drugs led to a therapeutic benefit. Hence, we assessed the cytotoxic effects of Carboplatin alone and in combination with several repurposed drugs (Pitavastatin, Metformin, Ivermectin, Itraconazole and Alendronate) in two tumoral models, i.e., Carboplatin (OVCAR8) and Carboplatin-Paclitaxel (OVCAR8 PTX R P) chemoresistant cell lines and in a non-tumoral (HOSE6.3) cell line. Cellular viability was measured using the Presto Blue assay, and the synergistic interactions were evaluated using the Chou–Talalay, Bliss Independence and Highest Single Agent reference models. Combining Carboplatin with Pitavastatin or Metformin displayed the highest cytotoxic effect and the strongest synergism among all combinations for OVCAR8 PTX R P cells, resulting in a chemotherapeutic effect superior to Carboplatin as a single agent. Concerning HOSE6.3 cells, combining Carboplatin with almost all the repurposed drugs demonstrated a safe pharmacological profile. Overall, we propose that Pitavastatin or Metformin could act synergistically in combination with Carboplatin for the management of high-grade serous carcinoma patients with a Carboplatin plus Paclitaxel resistance profile. - Combination of Antimalarial and CNS Drugs with Antineoplastic Agents in MCF-7 Breast and HT-29 Colon Cancer Cells: Biosafety Evaluation and Mechanism of Action
Diana Duarte, Mariana Nunes, Sara Ricardo, Nuno Vale
Biomolecules, 2022
Drug combination and drug repurposing are two strategies that allow to find novel oncological therapies, in a faster and more economical process. In our previous studies, we developed a novel model of drug combination using antineoplastic and different repurposed drugs. We demonstrated the combinations of doxorubicin (DOX) + artesunate, DOX + chloroquine, paclitaxel (PTX) + fluoxetine, PTX + fluphenazine, and PTX + benztropine induce significant cytotoxicity in Michigan Cancer Foundation-7 (MCF-7) breast cancer cells. Furthermore, it was found that 5-FU + thioridazine and 5-fluorouracil (5-FU) + sertraline can synergistically induce a reduction in the viability of human colorectal adenocarcinoma cell line (HT-29). In this study, we aim to (1) evaluate the biosafety profile of these drug combinations for non-tumoral cells and (2) determine their mechanism of action in cancer cells. To do so, human fetal lung fibroblast cells (MRC-5) fibroblast cells were incubated for 48 h with all drugs, alone and in combination in concentrations of 0.25, 0.5, 1, 2, and 4 times their half-maximal inhibitory concentration (IC50). Cell morphology and viability were evaluated. Next, we designed and constructed a cell microarray to perform immunohistochemistry studies for the evaluation of palmitoyl-protein thioesterase 1 (PPT1), Ki67, cleaved-poly (ADP-ribose) polymerase (cleaved-PARP), multidrug resistance-associated protein 2 (MRP2), P-glycoprotein (P-gp), and nuclear factor-kappa-B (NF-kB) p65 expression. We demonstrate that these combinations are cytotoxic for cancer cells and safe for non-tumoral cells at lower concentrations. Furthermore, it is also demonstrated that PPT1 may have an important role in the mechanism of action of these combinations, as demonstrated by their ability to decrease PPT1 expression. These results support the use of antimalarial and central nervous system (CNS) drugs in combination regimens with chemotherapeutic agents; nevertheless, additional studies are recommended to further explore their complete mechanisms of action. - Chemoresistance in ovarian cancer: The role of malignant ascites
Mariana Nunes, Sara Ricardo
Ovarian Cancer, 2022 - Pitavastatin and Ivermectin Enhance the Efficacy of Paclitaxel in Chemoresistant High-Grade Serous Carcinoma
Mariana Nunes, Diana Duarte, Nuno Vale, Sara Ricardo
Cancers, 2022 - InfectionCMA: A Cell MicroArray Approach for Efficient Biomarker Screening in In Vitro Infection Assays
Ana C. Magalhães, Sara Ricardo, Ana C. Moreira, Mariana Nunes, Margarida Tavares, et al.
Pathogens, 2022 - Corrigendum: Generation of Two Paclitaxel-Resistant High-Grade Serous Carcinoma Cell Lines With Increased Expression of P-Glycoprotein(Front. Oncol., (2021), 11, (752127), 10.3389/fonc.2021.752127)
Mariana Nunes, Patrícia M. A. Silva, Ricardo Coelho, Carla Pinto, Albina Resende, et al.
Frontiers in Oncology, 2022 - Mesothelin Expression Is Not Associated with the Presence of Cancer Stem Cell Markers SOX2 and ALDH1 in Ovarian Cancer
Mariana Nunes, Francisca Pacheco, Ricardo Coelho, Dina Leitão, Sara Ricardo, et al.
International Journal of Molecular Sciences, 2022 - Generation of Two Paclitaxel-Resistant High-Grade Serous Carcinoma Cell Lines With Increased Expression of P-Glycoprotein
Mariana Nunes, Patrícia M. A. Silva, Ricardo Coelho, Carla Pinto, Albina Resende, et al.
Frontiers in Oncology, 2021 - Recycling the purpose of old drugs to treat ovarian cancer
Mariana Nunes, Miguel Henriques Abreu, Carla Bartosch, Sara Ricardo
International Journal of Molecular Sciences, 2020 - Regulation of invasion and peritoneal dissemination of ovarian cancer by mesothelin manipulation
Ricardo Coelho, Sara Ricardo, Ana Luísa Amaral, Yen-Lin Huang, Mariana Nunes, et al.
Oncogenesis, 2020 - Understand the potential role of aureobasidium pullulans, a resident microorganism from grapevine, to prevent the infection caused by Diplodia seriata
Cátia Pinto, Valéria Custódio, Mariana Nunes, Aurélie Songy, Fanja Rabenoelina, et al.
Frontiers in Microbiology, 2018 - Lasiodiplodia theobromae as a producer of biotechnologically relevant enzymes
Carina Félix, Sofia Libório, Mariana Nunes, Rafael Félix, Ana Duarte, et al.
International Journal of Molecular Sciences, 2018
