Departamento de Genética Humana
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Browsing Departamento de Genética Humana by Field of Science and Technology (FOS) "Ciências Médicas::Ciências da Saúde"
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- Acute venous thromboembolism plasma and red blood cell metabolomic profiling reveals potential new early diagnostic biomarkers: observational clinical studyPublication . Febra, Claúdia; Saraiva, Joana; Vaz, Fátima; Soares, Nelson; Penque, PenqueBackground: Venous thromboembolism (VTE) is a leading cause of cardiovascular mortality. The diagnosis of acute VTE is based on complex imaging exams due to the lack of biomarkers. Recent multi-omics based research has contributed to the development of novel biomarkers in cardiovascular diseases. Our aim was to determine whether patients with acute VTE have differences in the metabolomic profile compared to non-acute VTE. Methods: This observational trial included 62 patients with clinical suspicion of acute deep vein thrombosis or pulmonary embolism, admitted to the emergency room. There were 50 patients diagnosed with acute VTE and 12 with non-acute VTE conditions and no significant differences were found between the two groups for clinical and demographic characteristics. Metabolomics assays identified and quantified a final number of 91 metabolites in plasma and 55 metabolites in red blood cells (RBCs). Plasma from acute VTE patients expressed tendency to a specific metabolomic signature, with univariate analyses revealing 23 significantly different molecules between acute VTE patients and controls (p < 0.05). The most relevant metabolic pathway with the strongest impact on the acute VTE phenotype was D-glutamine and D-glutamate (p = 0.001, false discovery rate = 0.06). RBCs revealed a specific metabolomic signature in patients with a confirmed diagnosis of DVT or PE that distinguished them from other acutely diseased patients, represented by 20 significantly higher metabolites and four lower metabolites. Three of those metabolites revealed high performant ROC curves, including adenosine 3',5'-diphosphate (AUC 0.983), glutathione (AUC 0.923), and adenine (AUC 0.91). Overall, the metabolic pathway most impacting to the differences observed in the RBCs was the purine metabolism (p = 0.000354, false discovery rate = 0.68). Conclusions: Our findings show that metabolite differences exist between acute VTE and nonacute VTE patients admitted to the ER in the early phases. Three potential biomarkers obtained from RBCs showed high performance for acute VTE diagnosis. Further studies should investigate accessible laboratory methods for the future daily practice usefulness of these metabolites for the early diagnosis of acute VTE in the ER.
- Alternative Splicing at the Crossroad of Inflammatory Bowel Diseases and Colitis-Associated Colon CancerPublication . Matos, Paulo; Jordan, PeterSimple Summary: Patients with ulcerative colitis (UC) face a higher risk of developing colorectal cancer (CRC) due to chronic inflammation, a known promoter of tumour growth. Here, we review the molecular differences between colitis-associated cancer (CAC) and sporadic CRC, with a focus on “alternative splicing”, a mechanism by which the same gene can produce various protein forms. We explore how inflammation triggers changes in this process, increasing cancer risk for UC patients. The revised data emphasize that additional research into these molecular changes could help identify new biomarkers (molecules that indicate disease progression) and pave the way for innovative treatments targeting these alterations. Such advances would improve outcomes and quality of life for patients while contributing to cancer prevention and care.
- CCL2 expression predicts clinical outcomes and regulates E-cadherin and angiogenesis in pituitary tumoursPublication . Silva, Ana Luísa; Barry, Sayka; Lopes-Pinto, Mariana; Joaquim, Rita; Miranda, Catarina; Reis, Fábio; Miranda, Micaella; Matos, Paulo; Suleyman, Oniz; Oliveira, Tiago; López-Presa, Dolores; Borrecho, Gonçalo; Tortosa, Francisco; Faria, Claúdia C.; Korbonits, Márta; Marques, PedroThe crosstalk between tumour cells and microenvironment components in pituitary neuroendocrine tumours (PitNETs), including chemokines, may impact tumour behaviour and clinical outcomes. CCL2 was previously identified as a key chemokine in PitNETs, but its role remains unknown. We aimed to study the role of CCL2 in defining the phenotype and clinical outcomes of PitNETs and in regulating macrophage chemotaxis, epithelial-to-mesenchymal transition (EMT) and angiogenesis. We studied CCL2 and E-cadherin expression, macrophages (CD68 and CD163) and vessels (CD31) in samples from 86 PitNET patients. Higher CCL2 mRNA expression was found in patients who required multimodal and multiple treatments and had active disease at the last follow-up. Higher CCL2 immunoreactivity was observed in patients with larger PitNETs. Among somatotroph tumours, CCL2 mRNA expression correlated with serum IGF-1 at the last follow-up. CCL2 mRNA expression levels correlated negatively with CDH1 expression and with E-cadherin complete membranous staining. In vitro, CCL2 downregulated E-cadherin expression in GH3 cells but did not affect cell morphology or migration. CCL2 expression correlated with the number of vessels, vessel perimeter and vessel area in PitNETs but not with PitNET-infiltrating macrophages. Our data suggest that CCL2 may lead to (or is at least a predictive marker of) poorer clinical outcomes and more difficult-to-treat PitNETs, potentially through its regulatory effects on different tumour-related mechanisms beyond immune cell chemotaxis, including in the activation of the EMT pathway and modulation of angiogenesis in PitNETs. Further studies are needed to corroborate our findings and to validate CCL2 as a potential predictive marker and therapeutic target in PitNETs.
- Lactate-coated polyurea-siRNA dendriplex: a gene therapy-directed and metabolism-based strategy to impair glioblastoma (GBM)Publication . Martins, Filipa; Arada, Renata; Barros, Hélio; Matos, Paulo; Ramalho, José; Ceña, Valentín; Bonifácio, Vasco D.B.; Gonçalves, Luís G.; Serpa, JacintaGlioblastoma (GBM) is a highly lethal disease with limited treatment options due to its infiltrative nature and the lack of efficient therapy able to cross the protective blood-brain barrier (BBB). GBMs are metabolically characterized by increased glycolysis and glutamine dependence. This study explores a novel metabolism-based therapeutic approach using a polyurea generation 4 dendrimer (PURE) surface functionalized with lactate (LA) (PURE-LA), to take advantage of glucose-dependent monocarboxylate transporters (MCTs) overexpression, loaded with selenium-chrysin (SeChry) and temozolomide (TMZ) or complexed with anti-glutaminase (GLS1) siRNAs to abrogate glutamine dependence. The nanoparticles (PURE-LA) were efficient vehicles for cytotoxic compounds delivery, since SeChry@PURE-LA and TMZ@PURE-LA induced significant cell death in GBM cell lines, particularly in U251, which exhibits higher MCT1 expression. The anti-GLS1 siRNA-dendriplex with PURE-LA (PURE-LA-anti-GLS1-siRNA) knocked down GLS1 in the GBM cell lines. In two in vitro BBB models, these dendriplexes successfully crossed the BBB, decreased GLS1 expression and altered the exometabolome of GBM cell lines, concomitantly with autophagy activation. Our findings highlight the potential of targeting glucose and glutamine pathways in GBM using dendrimer-based nanocarriers, overcoming the BBB and disrupting key metabolic processes in GBM cells. PURE-LA-anti-GLS1-siRNA dendriplexes cross the blood-brain barrier (BBB) and impair glioblastoma (GBM) metabolism. The BBB is formed by a thin monolayer of specialized brain microvascular endothelial cells joined together by tight junctions that selectively control the passage of substances from the blood to the brain. It is a major obstacle in the treatment of GBM, since many chemotherapeutic drugs are unable to penetrate the brain. Therefore, we developed a strategy to overcome this obstacle: a lactate-coated polyurea dendrimer generation 4 (PURE) able to cross the BBB in vitro, that act as a nanocarrier of drugs and siRNA to the GBM cells. PURE-LA are nanoparticles functionalized with lactate (LA) to target MCT1, a lactate transporter highly expressed by GBM cells. Moreover, a complex of this nanoparticle with anti-GLS1 (glutaminase) siRNA (PURE-LA-anti-GLS1-siRNA) was made, to target glutamine metabolism. It efficiently knocked down GLS1. Moreover, PURE-LA loaded with SeChry led to BBB disruption.
- The mechanism of nonsense-mediated mRNA decay and its playersPublication . Subtil, Catarina; Loison, Luísa; Santos, Rafaela LacerdaNonsense-mediated mRNA decay (NMD) is a post-transcriptional surveillance mechanism harbouring two functions: identification and degradation of transcripts containing premature translation-termination codons (PTC), preventing deleterious effects in the cell; and downregulation of mRNAs in response to cellular needs, maintaining the quality of gene expression. One-third of gene mutations in human genetic diseases, including cancer, are due to nonsense mutations or frameshift that result in transcripts harbouring nonsense codons and can be eliminated by NMD. The several factors involved in this mechanism may act in diverse ways depending on the set of transcripts to be regulated, contributing to the branching of this pathway. Cytoplasmic DIS3 exosome independent 3′-5′ exoribonuclease 2 (DIS3L2) has been reported as one of the factors to induce NMD targets decay. Therefore, this study aims to enlighten how DIS3L2 functions in NMD: i) analyse the correlation between the distinct branches of NMD and cervical and uterus cancer; ii) investigate which branch guides DIS3L2-mediated degradation; and iii) test which region of the NMD/DIS3L2-targets mediate DIS3L2 degradation through a system of hybrid-genes. For our first aim, we detected no correlation between any of the branches of NMD and uterus and cervical cancer. Each factor acts independently. In our second objective, we analysed the mRNA expression of five transcripts, but none displayed a significant alteration in their expression to infer a correlation between DIS3L2 and a particular NMD branch. Relatively to the last aim, we successfully cloned three out of the four constructs but due to time constrictions we could not continue. Nonetheless, further testing is needed to better understand this mechanism and how transcript degradation is mediated, including the diverse factors needed for its activation, which might be the key to future advanced therapeutic strategies.
- Occupational second-hand smoke exposure: A comparative shotgun proteomics study on nasal epithelia from healthy restaurant workersPublication . Neves, Sofia; Pacheco, Solange; Vaz, Fátima; James, Peter; Simões, Tânia; Penque, Deborah; NevesNon-smokers exposed to second-hand smoke (SHS) present risk of developing tobacco smoke-associated pathologies. To investigate the airway molecular response to SHS exposure that could be used in health risk assessment, comparative shotgun proteomics was performed on nasal epithelium from a group of healthy restaurant workers, non-smokers (never and former) exposed and not exposed to SHS in the workplace. HIF1α-glycolytic targets (GAPDH, TPI) and proteins related to xenobiotic metabolism, cell proliferation and differentiation leading to cancer (ADH1C, TUBB4B, EEF2) showed significant modulation in non-smokers exposed. In never smokers exposed, enrichment of glutathione metabolism pathway and EEF2-regulating protein synthesis in genotoxic response were increased, while in former smokers exposed, proteins (LYZ, ATP1A1, SERPINB3) associated with tissue damage/regeneration, apoptosis inhibition and inflammation that may lead to asthma, COPD or cancer, were upregulated. The identified proteins are potential response and susceptibility/risk biomarkers for SHS exposure.