Percorrer por autor "Baltazar, Fátima"
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- 3-Bromopyruvate boosts the effect of chemotherapy in acute myeloid leukemia by a pro-oxidant mechanismPublication . Vieira, Joana Pereira; Preto, Ana; Granja, Sara; Queirós, Odília; Celeiro, Sónia Pires; Ko, Young Hee; Casal, Margarida; Matos, Catarina Barbosa; Baltazar, Fátima; Granja, SaraAcute myeloid leukemia (AML) comprises a diverse group of blood cancers with varying genetic, phenotypic, and clinical traits, making development of targeted therapy challenging. Metabolic reprogramming in AML has been described as relevant for chemotherapy effectiveness. 3-Bromopyruvate (3-BP) is an anticancer agent that undermines energy metabolism of cancer cells. However, the effect of 3-BP in hematologic malignancies, such as AML, needs further investigation. Thus, we aimed to explore 3-BP as a chemo-sensitizing agent in AML. Different approaches of combining 3-BP with classical chemotherapy (daunorubicin and cytarabin) were tested in diverse AML cell lines. Cell sensitivity to the different drug combinations was analyzed by Trypan blue staining. The effect of pre-treatment with a non-toxic concentration of 3-BP was assessed on the AML cell metabolic profile (Western blot and immunofluorescence), mitochondrial activity (cytometry flow), and antioxidant capacity (colorimetric detection kit). KG-1 and MOLM13 cells showed increased sensitivity to chemotherapy (decreased EC 50 values) after exposure to a non-toxic concentration (5 μ M) of 3-BP. In both cell lines, 5 glucose consumption without changing extracellular lactate levels. 5 μ μ M 3-BP decreased M 3-BP treatment increased reactive oxygen species levels and decreased cell antioxidant capacity by depleting reduced glutathione levels in both KG-1 and MOLM13 cells. Our results demonstrate that non-toxic concentrations of 3-BP enhance the effect of classical chemotherapy in AML cells through a pro-oxidant mechanism. These data unveiled a new approach for AML treatment, using 3-BP or other pro-oxidant agents as co-adjuvants of chemotherapy, subsiding chemotherapy- induced side effects.
- Combination therapy with CD147‐targeted nanoparticles carrying phenformin decreases lung cancer growthPublication . Pereira-Nunes, Andreia; Ferreira, Helena; Abreu, Sara; Guedes, Marta; Neves, Nuno M.; Baltazar, Fátima; Granja, Sara; Granja, SaraLung cancer is one of the most fatal cancers worldwide. Resistance to conventional therapies remains a hindrance to patient treatment. Therefore, the development of more effective anti-cancer therapeutic strategies is imperative. Solid tumors exhibit a hyperglycolytic phenotype, leading to enhanced lactate production; and, consequently, its extrusion to the tumor microenvironment. Previous data reveals that inhibition of CD147, the chaperone of lactate transporters (MCTs), decreases lactate export in lung cancer cells and sensitizes them to phenformin, leading to a drastic decrease in cell growth. In this study, the development of anti-CD147 targeted liposomes (LUVs) carrying phenformin is envisioned, and their efficacy is evaluated to eliminate lung cancer cells. Herein, the therapeutic effect of free phenformin and anti-CD147 antibody, as well as the efficacy of anti-CD147 LUVs carrying phenformin on A549, H292, and PC-9 cell growth, metabolism, and invasion, are evaluated. Data reveals that phenformin decreases 2D and 3D-cancer cell growth and that the anti-CD147 antibody reduces cell invasion. Importantly, anti-CD147 LUVs carrying phenformin are internalized by cancer cells and impaired lung cancer cell growth in vitro and in vivo. Overall, these results provide evidence for the effectiveness of anti-CD147 LUVs carrying phenformin in compromising lung cancer cell aggressiveness.
- Glucose metabolism as a potential therapeutic target in Cytarabine-resistant acute Myeloid leukemiaPublication . Pereira-Vieira, Joana; Weber, Daniela D.; Silva, Sâmia; Barbosa-Matos, Catarina; Granja, Sara; Reis, Rui Manuel; Queirós, Odília; Ko, Young H.; Kofler, Barbara; Casal, Margarida; Baltazar, Fátima; Granja, SaraAltered glycolytic metabolism has been associated with chemoresistance in acute myeloid leukemia (AML). However, there are still aspects that need clarification, as well as how to explore these metabolic alterations in therapy. In the present study, we aimed to elucidate the role of glucose metabolism in the acquired resistance of AML cells to cytarabine (Ara-C) and to explore it as a therapeutic target. Resistance was induced by stepwise exposure of AML cells to increasing concentrations of Ara-C. Ara-C-resistant cells were characterized for their growth capacity, genetic alterations, metabolic profile, and sensitivity to different metabolic inhibitors. Ara-C-resistant AML cell lines, KG-1 Ara-R, and MOLM13 Ara-R presented different metabolic profiles. KG-1 Ara-R cells exhibited a more pronounced glycolytic phenotype than parental cells, with a weaker acute response to 3-bromopyruvate (3-BP) but higher sensitivity after 48 h. KG-1 Ara-R cells also display increased respiration rates and are more sensitive to phenformin than parental cells. On the other hand, MOLM13 Ara-R cells display a glucose metabolism profile similar to parental cells, as well as sensitivity to glycolytic inhibitors. These results indicate that acquired resistance to Ara-C in AML may involve metabolic adaptations, which can be explored therapeutically in the AML patient setting who developed resistance to therapy.
- In vitro and in vivo evaluation of novel chromeno[2,3-d]pyrimidinones as therapeutic agents for triple negative breast cancerPublication . Carvalho, Luísa; Lima, Fábio Pedroso de; Cerqueira, Mónica; Silva, Ana; Pontes, Olívia; Oliveira-Pinto, Sofia; Guerreiro, Sara; Costa, Marta D.; Granja, Sara; Maciel, Patrícia; Longatto-Filho, Adhemar; Baltazar, Fátima; Proença, Fernanda; Costa, Marta; Granja, SaraTriple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, and the limited therapeutic options show poor efficacy in patients, associated to severe side effects and development of resistance. Considering that chromene-based scaffolds proved to be attractive candidates for cancer therapy, herein we prepared new chromeno[2,3-d]pyrimidinone derivatives by a simple two step procedure, starting from the reaction of cyanoacetamide and a salicylaldehyde. A cell viability screening in several breast cancer cell lines allowed to identify two promising compounds with IC50 values in the low micromolar range for TNBC cells. These chromenes inhibited cell proliferation, induced cell cycle arrest and triggered cell death through apoptosis. In vivo studies revealed a safe profile in invertebrate and vertebrate animal models and confirmed their capacity to inhibit tumor growth in the CAM model, inducing significant tumor regression after 4 days of treatment. The two compounds identified in this study are promising drug candidates for TNBC treatment and valuable hits for future optimization, using the versatile synthetic platform that was developed.
- MCT1 is a new prognostic biomarker and its therapeutic inhibition boosts response to Temozolomide in human glioblastomaPublication . Gonçalves, Vera Miranda; Gonçalves, Céline S.; Granja, Sara; Castro, Joana Vieira de; Reis, Rui M.; Costa, Bruno M.; Baltazar, Fátima; Granja, SaraGlioblastoma, the brain tumour with highest prevalence and lethality, exhibits a characteristic glycolytic phenotype with increased lactate production. Recently, we reported a MCT1 overexpression in GBMs tumours, being associated to tumour growth and aggressiveness. Thus, we aimed to disclose the role of MCT1 in GBM prognosis and in vivo therapy response. Importantly, MCT1 overexpression is associated with poor prognosis of GBM. Moreover, MCT1 inhibition retards GBM tumour growth and boosts response to temozolomide treatment.
- Metabolism-targeted therapy in NSCLC – A new theranostics inhalation approach using lactate functionalized and selenium-chrysin loaded nanoparticles (SeChry@PUREG4-LA24)Publication . Mendes, Cindy; Martins, Filipa; Granja, Sara; Gonçalves, Joana; Barros, Hélio; Casimiro, Teresa; Ricardo, Ana Aguiar; Silva, Fernanda; Abreu, Bruna; Cristovão, Miguel; André, Saudade; Pereira, Sofia A.; Baltazar, Fátima; Marques, Helena Cabral; Gaspar, Maria Manuela; Gonçalves, Luís G.; Bonifácio, Vasco D. B.; Serpa, Jacinta; Granja, SaraLung cancer is one of the most lethal cancers globally, primarily due to delayed diagnosis and lack of specific and effective therapy. Increased lactate production and consumption, along with cysteine metabolic reliance, are features identified in NSCLC in our recent studies. Cancer metabolic remodeling leads to excessive ROS production, triggering oxidative stress, promoting angiogenesis, causing cellular and tissue damage, and contributing to various pathophysiological changes. This study aimed to investigate the therapeutic potential of selenium–chrysin (SeChry), a cysteine metabolism inhibitor, and its delivery targeted at MCT1 by encapsulation in fourth-generation polyurea dendrimers functionalized with lactic acid (PUREG4-LA24), the nanoformulation SeChry@PUREG4-LA24, in NSCLC. We explored the impact of SeChry nanoformulation on cell death mechanisms, including ferroptosis, and its influence on angiogenesis in in vitro and in vivo models. SeChry@PUREG4-LA24 induces cell death through the induction of intracellular ROS and lipid peroxides, resulting in distinct expression patterns of ferroptosis-associated genes across cell lines. Experiments using chicken embryo chorioallantoic membrane (CAM) and mouse orthotopic xenograft models revealed a trend toward decreased tumor growth and angiogenesis with SeChry@PUREG4-LA24 administration. These findings suggest the potential of SeChry@PUREG4-LA24 as an innovative therapeutic approach for NSCLC, highlighting its impact on cell death mechanisms and anti-angiogenic effects.
- Targeting lysosomes in colorectal cancer: exploring the anticancer activity of a New Benzo[a]phenoxazine derivativePublication . Ferreira, João C. C.; Granja, Sara; Almeida, Ana F.; Baltazar, Fátima; Gonçalves, M. Sameiro T.; Preto, Ana; Sousa, Maria JoãoColorectal cancer (CRC) has been ranked as one of the cancer types with a higher incidence and one of the most mortal. There are limited therapies available for CRC, which urges the finding of intracellular targets and the discovery of new drugs for innovative therapeutic approaches. In addition to the limited number of effective anticancer agents approved for use in humans, CRC resistance and secondary effects stemming from classical chemotherapy remain a major clinical problem, reinforcing the need for the development of novel drugs. In the recent years, the phenoxazines derivatives, Nile Blue analogues, have been shown to possess anticancer activity, which has created interest in exploring the potential of these compounds as anticancer drugs. In this context, we have synthetized and evaluated the anticancer activity of different benzo[a]phenoxazine derivatives for CRC therapy. Our results revealed that one particular compound, BaP1, displayed promising anticancer activity against CRC cells. We found that BaP1 is selective for CRC cells and reduces cell proliferation, cell survival, and cell migration. We observed that the compound is associated with reactive oxygen species (ROS) generation, accumulates in the lysosomes, and leads to lysosomal membrane permeabilization, cytosolic acidification, and apoptotic cell death. In vivo results using a chicken embryo choriollantoic membrane (CAM) assay showed that BaP1 inhibits tumor growth, angiogenesis, and tumor proliferation. These observations highlight that BaP1 as a very interest ing agent to disturb and counteract the important roles of lysosomes in cancer and suggests BaP1 as a promising candidate to be exploited as new anticancer lysosomal-targeted agent, which uses lysosome membrane permeabilization (LMP) as a therapeutic approach in CRC.