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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.
- 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.
- String/Cdc25 phosphatase is a suppressor of Tau-associated neurodegenerationPublication . Oliveira, Andreia C.; Santos, Madalena; Pinho, Mafalda; Lopes, Carla S.Tau pathology is defined by the intracellular accumulation of abnormally phosphorylated Tau (MAPT) and is prevalent in several neurodegenerative disorders. The identification of modulators of Tau abnormal phosphorylation and aggregation is key to understanding disease progression and developing targeted therapeutic approaches. In this study, we identified String (Stg)/Cdc25 phosphatase as a suppressor of abnormal Tau phosphorylation and associated toxicity. Using a Drosophila model of tauopathy, we showed that Tau dephosphorylation by Stg/Cdc25 correlates with reduced Tau oligomerization, brain vacuolization and locomotor deficits in flies. Moreover, using a disease mimetic model, we provided evidence that Stg/Cdc25 reduces Tau phosphorylation levels independently of Tau aggregation status and delays neurodegeneration progression in the fly. These findings uncover a role for Stg/Cdc25 phosphatases as regulators of Tau biology that extends beyond their well-characterized function as cell-cycle regulators during cell proliferation, and indicate Stg/Cdc25-based approaches as promising entry points to target abnormal Tau phosphorylation.
- Inking cell blocks improves scanner detection for diagnosis in pathologyPublication . Eloy, Catarina; Neves, Beatriz; Vale, João; Campelos, Sofia; Curado, Mónica; Polónia, AntónioCell blocks may be hard to be totally automatically detected by the scanner (ADS),generating incomplete whole slide images (WSIs), with areas that are not scanned,leading to possible false negative diagnosis. The aim of this study is to test if inkingthe cell blocks helps increasing ADS. Test 1: 15 cell blocks were sectioned, one halfinked black (1HB) and the other inked green (1HG). Each of the halves was individu-ally processed to generate a WSI stained by the H&E. 1HBs and 1HGs had similarscanning time (median 59 s vs. 65 s, p = .126) and file sizes (median 382 Mbvs. 381 Mb, p = .567). The black ink interfered less in the observation (2.2%vs. 44.4%; p < .001) than in the green one. Test 2: 15 cell blocks were sectioned, onehalf inked black (2HB) and the other left unstained/null (2HN). Each of the halveswas individually processed to generate three WSIs—one HE, one periodic-acid Schiff(PAS), and one immunostained by cytokeratin AE1&AE3 (CKAE1AE3). HE and PASWSIs from both 2HN and 2HB groups were all totally ADS and had similar scanningtimes and file sizes. Concerning immunostaining with CKAE1AE3: ADS (46.7%vs. 93.3%; p = .014), median time for scanning (57 s vs. 83 s; p < .001) and file size(178 Mb vs. 338 Mb; p < .001) were reduced significantly in the 2HN group in com-parison with the 2HB. Although increasing scanning time and file size, inking the cellblocks helps increasing ADS after immunostaining, improving the safety and effi-ciency of the digital pathology workflow.
- Optimizing the management of thyroid specimens to efficiently generate whole slide images for diagnosisPublication . Eloy, Catarina; Vale, João; Barros, Mariana; Oliveira, Diana; Mesquita, Morgana; Curado, Mónica; Pinto, João; Polónia, AntónioTransition from optical to digital observation requires an additional procedure in the pathology laboratory, the scanning of glass slides, leading to increased time and digital archive consumption. Thyroid surgical samples often carry the need to collect several tissue fragments that generate many slides to be scanned. This study evaluated the impact of using different inking colours for the surgical margin, section thickness, and glass slide type, in the consumption of time and archive. The series comprehended 40 nodules from 30 patients, including 34 benign nodules in follicular nodular disease, 1 NIFTP, and 5 papillary carcinomas. In 12 nodules, the dominant pattern was microfollicular/solid and in 28 it was macrofollicular. Scanning times/mm2 were longer in red-inked fragments in comparison to green (p=0.04) and black ones (p=0.024), and in blue-inked in comparison to green ones (p=0.043). File sizes/mm2 were larger in red-inked fragments in comparison to green (p=0.008) and black ones (p=0.002). The dominant pattern microfollicular/solid was associated with bigger file size/ mm2 in comparison with the macrofollicular one (p
- Using artificial intelligence to prioritize pathology samples: report of a test drivePublication . Rienda, Iván; Vale, João; Pinto, João; Polónia, António; Eloy, CatarinaThe digital transformation of pathology, through automation and computational tools, addresses current challenges in the field. This study evaluates Paige Pan Cancer, a novel artificial intelligence tool based on the Virchow foundation model, designed to flag invasive cancer in haematoxylin and eosin-stained slides from 16 primary tissue types. Using 62 cases from the Ipatimup Pathology Laboratory, we found the tool had a sensitivity of 93.3% and specificity of 87.5% in biopsies, and 94.7% sensitivity and 75.0% specificity in resections. Overall accuracy was 90.3%. Despite some misclassifications, Paige Pan Cancer demonstrates high sensitivity as a multi-organ screening tool in clinical practice.
- A novel deleterious variant and a founder effect in four new families of MBD4-Associated Neoplasia Syndrome recruited over a period of 20 YearsPublication . Querido, Inês; Pinto, Carla; Arinto, Patrícia; Brandão, Andreia; Santos, Catarina; Pinheiro, Manuela; Guerra, Joana; Silva, João; Peixoto, Ana; Teixeira, Manuel R.; Pinto, CarlaDNA glycosylases play a crucial role in DNA repair mediated by the base excision repair (BER) pathway, and alterations in these enzymes have been associated with hereditary cancer predisposition. Recently, germline biallelic loss-of-function variants in MBD4 were shown to be responsible for a novel autosomal recessive multi-tumor predisposition syndrome, provisionally denominated as MBD4-associated neoplasia syndrome and characterized by the association of adenomatous polyposis, colorectal cancer, and acute myeloid leukemia (AML). Here, we studied the MBD4 gene in five individuals from four families affected by adenomatous polyposis and AML, who had been referred for genetic counselling at a single institution over a period of approximately 20 years. All patients with this phenotype presented homozygous deleterious germline variants in MBD4, of which one is a founder variant recurrent in three of the families, and another variant has not been previously described in the literature. Our work allowed a molecular diagnosis for these families and significantly contributes to expanding the knowledge about this emerging syndrome caused by MBD4 constitutional deficiency.
- The role of multi-organ cancer predisposition genes in the risk of inherited and histologically diverse gastric cancerPublication . Carvajal-Carmona, Luis G.; Pinto, Carla; Pinto, CarlaApproximately 10% of cases with gastric cancer (GC) exhibit familial clustering, however, only 1–3% of cases can be explained by two known hereditary syndromes: Hereditary Diffuse Gastric Cancer (HDGC) caused by CDH1 and CTNNA1 pathogenic germline variants; and Gastric Adenocarcinoma and Proximal Polyposis of the Stomach (GAPPS), caused by germline variants in APC 1B promoter. Familial intestinal gastric cancer (FIGC) has been defined clinically, but it remains mostly genetically unexplained. Likewise, the heritability of mixed histology GC remains to be known. We aimed to estimate the frequency of known cancer predisposition gene variants in GC cases with and without a cancer family history, diverse histological subtypes, and varied age of onset. We evaluated the contribution of pathogenic or likely pathogenic (P/LP) variants in well-established moderate-to-high penetrance multi-organ cancer predisposition genes for GC risk in a large international multi-centre retrospective cohort study involving 750 patients with GC of early-onset or family history of cancer, either by panel sequencing or whole exome sequencing (WES). Panel sequencing was conducted on 328 cases, while WES was performed on the remaining 422. Tumour sequence analyses were performed on samples from 15 patients with P/LP variants. Mutations identified in five index cases were also tested in their relatives. We identified 45 patients (6%) with P/LP variants in: ATM (17 cases), BRCA2 (10 cases), MLH1 (five cases), TP53 (three cases), BRCA1, PALB2, RAD51D, and CHEK2 (two patients each), and RAD51C and PMS2 (one case each), all of which were mutually exclusive. The P/LP variant prevalence was higher in intestinal (9.8%) than in diffuse (4.3%) or mixed GC (4.5%) (p-value = 0.023), without difference per mutated gene by histological subtypes. Only 16 of the 45 patients who carried P/LP variants fulfilled the National Comprehensive Cancer Network genetic testing criteria of at least one cancer predisposition syndrome. Our findings indicate that a broader panel of cancer predisposition genes, beyond CDH1 and CTNNA1, should be included in gene panels to investigate germline variants in patients with GC. This would be especially beneficial when there is a family history of cancer, irrespective of histology subtype, as it would increase the chance of identifying patients who could benefit from risk reduction, targeted treatment, and surveillance of other cancer types.
- Signature cytokine-associated transcriptome analysis of effector γδ T cells identifies subset-specific regulators of peripheral activationPublication . Inácio, Daniel; Amado, Tiago; Pamplona, Ana; Sobral, Daniel; Cunha, Carolina; Santos, Rita F.; Oliveira, Liliana; Rouquié, Nelly; Carmo, Alexandre M.; Lesourne, Renaud; Gomes, Anita Q.; Santos, Bruno Silva; Santos, Ana Ritaγδ T cells producing either interleukin-17A (γδ17 cells) or interferon-γ (γδIFN cells) are generated in the mouse thymus, but the molecular regulators of their peripheral functions are not fully characterized. Here we established an Il17a-GFP:Ifng-YFP double-reporter mouse strain to analyze at unprecedented depth the transcriptomes of pure γδ17 cell versus γδIFN cell populations from peripheral lymph nodes. Within a very high fraction of differentially expressed genes, we identify a panel of 20 new signature genes in steady-state γδ17 cells versus γδIFN cells, which we further validate in models of experimental autoimmune encephalomyelitis and cerebral malaria, respectively. Among the signature genes, we show that the co-receptor CD6 and the signaling protein Themis promote the activation and proliferation of peripheral γδIFN cells in response to T cell antigen receptor stimulation in vitro and to Plasmodium infection in vivo. This resource can help to understand the distinct activities of effector γδ T cell subsets in pathophysiology.