Expanded national database collection and data coverage in the FINDbase worldwide database for clinically relevant genomic variation allele frequencies

FINDbase (http://www.findbase.org) is a comprehensive data repository that records the prevalence of clinically relevant genomic variants in various populations worldwide, such as pathogenic variants leadingmostly tomonogenic disorders and pharmacogenomics biomarkers. The database also records the incidence of rare genetic diseases in various populations, all in well-distinct data modules. Here, we report extensive data content updates in all data modules, with direct implications to clinical pharmacogenomics. Also, we report significant new developments in FINDbase, namely (i) the release of a new version of the ETHNOS software that catalyzes development curation of national/ethnic genetic databases, (ii) the migration of all FINDbase data content into 90 distinct national/ethnicmutation databases, all built around Microsoft's PivotViewer (http://www.getpivot.com) software (iii) new data visualization tools and (iv) the interrelation of FINDbase with DruGeVar database with direct implications in clinical pharmacogenomics. The abovementioned updates further enhance the impact of FIND-base, as a key resource for Genomic Medicine applications

Expanded national database collection and data coverage in the FINDbase worldwide database for clinically relevant genomic variation allele frequencies

Peer reviewe

Study of the role of coagulation factors Xa and thrombin in atherothrombosis

Endothelial cells play a crucial role in atherosclerosis. Endothelial dysfunction contributes to the first stages of plaque formation through the recruitment of leukocytes to the endothelium. The rupture of the atherosclerotic plaque leads to platelet activation and thrombosis. Endothelial progenitor cells (EPCs) are pluripotent cells that differentiate into mature endothelial cells, contributing to endothelial regeneration. It has been proved that circulating CD34+ cells differentiate into EPCs after their interaction with platelets and that this interaction leads to further maturation into endothelial cells. Coagulation factors Xa (FXa) and thrombin, apart from their haemostatic role, exhibit also non-haemostatic cellular effects that are mediated through protease-activated receptors (PARs), which are found on various cell types, such as platelets and endothelial cells. The aim of the present study was to investigate the role of FXa and thrombin in platelet activation and aggregation, as well as their role in EPC activation. For this purpose, the role of these factors in platelet activation and aggregation, as well as the effect of the direct oral anticoagulants rivaroxaban and dabigatran, which target FXa and thrombin respectively, was studied using PRP, washed platelets and whole blood. Additionally, the role of PAR-1 in FXa- or thrombin-induced platelet activation and aggregation was studied using the selective PAR-1 antagonist, vorapaxar. Platelet activation and aggregation were evaluated using light transmittance aggregometry, impendance aggregometry and flow cytometry. Moreover, the role of PAR-1 in the differentiation of CD34+ cells into EPCs, as well as on the formation of CD34+ cells/platelets conjugates, were aso studied using flow cytometry. Consequently, the role of FXa and thrombin in late-outgrowth endothelial cell activation (OECs) was investigated using the membrane expression of the adhesion molecule ICAM-1, as well as the expression of MCP-1, as activation markers. The role of rivaroxaban and dabigatran, as well as the role of PAR-1 on OEC activation by FXa and thrombin, were also evaluated. The present study proved that FXa and thrombin are potent platelet agonists and that FXa exhibits a delayed aggregatory effect. Platelet activation by these factors is mediated mainly via PAR-1. Furthermore, rivaroxaban and dabigatran inhibit FXa- and thrombin-induced platelet aggregation in a dose-dependent manner, without showing selectivity over one factor. PAR-1 also mediates the differentiation of CD34+ cells into EPCs, as well as the formation of CD34+ cells/platelets conjugates. The present study also proved that FXa and thrombin induce the expression of ICAM-1 and MCP-1 from OECs, mainly though PAR-1 activation. Vorapaxar does not fully inhibit thrombin-induced ICAM-1 expression and MCP-1 secretion from OECs, whereas it fully inhibits the above expression from HUVECs, a result that suggests the contribution of PAR-4 in this expression from OECs. Rivaroxaban and dabigatran inhibit in a dose-dependent manner FXa- and thrombin-induced ICAM-1 expression and MCP-1 secretion, respectively. An interesting finding that was observed for the first time was the enhancement of the thrombin-induced ICAM-1 expression and MCP-1 secretion by rivaroxaban. This enchancement effect was inhibited by vorapaxar, showing the participation of PAR-1 in this action. In conclusion, platelet and endothelial cell activation by FXa and thrombin could contribute in atherothrombosis. In addition, their action on OECs could be beneficial on endothelial regeneration. Even though in the present study various cellular effects of FXa and thrombin were investigated, more studies are required in order to fully decipher their role, as well as the contribution of their respective drugs, in atherothrombosis, endothelial regeneration and angiogenesis.Τα ενδοθηλιακά κύτταρα και τα αιμοπετάλια διαδραματίζουν σημαντικό ρόλο στην αθηροθρόμβωση. Η ενδοθηλιακή δυσλειτουργία συμβάλλει στα πρώτα στάδια της αθηρωμάτωσης, διαμέσου της στρατολόγησης των λευκοκυττάρων στο ενδοθήλιο. Η ρήξη της αθηρωματικής πλάκας οδηγεί στην ενεργοποίηση των αιμοπεταλίων και τη θρόμβωση. Τα πρόδρομα ενδοθηλιακά κύτταρα (endothelial progenitor cells, EPCs) αποτελούν πολυδύναμα κύτταρα τα οποία διαφοροποιούνται σε ώριμα, συμμετέχοντας στην αναγέννηση του ενδοθηλίου. Είναι αποδεδειγμένο ότι τα κυκλοφορούντα CD34+ κύτταρα μετά από την αλληλεπίδρασή τους με τα αιμοπετάλια διαφοροποιούνται σε EPCs, ενώ η παραπάνω αλληλεπίδραση οδηγεί στην περαιτέρω ωρίμανση τους σε ώριμα ενδοθηλιακά κύτταρα. Οι παράγοντες πήξης Xa (factor Xa, FXa) και θρομβίνη, εκτός του αιμοστατικού τους ρόλου, εμφανίζουν μη αιμοστατικές κυτταρικές δράσεις που διαμεσολαβούνται από τους υποδοχείς που ενεργοποιούνται από πρωτεάσες (protease-activated receptors, PARs) και εντοπίζονται σε πληθώρα κυτταρικών τύπων, συμπεριλαμβανομένων των αιμοπεταλίων και των ενδοθηλιακών κυττάρων. Σκοπός της παρούσας διδακτορικής διατριβής ήταν η διερεύνηση της δράσης των FXa και θρομβίνης στην ενεργοποίηση και συσσώρευση των αιμοπεταλίων, καθώς και την ενεργοποίηση πρόδρομων ενδοθηλιακών κυττάρων. Για την επίτευξη του σκοπού αυτού, μελετήθηκε η επίδραση των παραγόντων αυτών στην αιμοπεταλιακή ενεργοποίηση και συσσώρευση σε PRP, πλυμένα αιμοπετάλια ή ολικό αίμα, καθώς και ο ρόλος των άμεσων από του στόματος αναστολέων του FXa και της θρομβίνης, rivaroxaban και dabigatran, αντίστοιχα. Ακόμη, μελετήθηκε ο ρόλος του υποδοχέα PAR-1 στην επαγόμενη από τον FXa ή τη θρομβίνη αιμοπεταλιακή ενεργοποίηση και συσσώρευση, με τη χρήση του εκλεκτικού ανταγωνιστή του υποδοχέα, vorapaxar. Η αιμοπεταλιακή ενεργοποίηση και συσσώρευση εκτιμήθηκε με τις μεθόδους της συσσωρευομετρίας οπτικής διαπερατότητας, συσσωρευομετρίας εμπέδησης και κυτταρομετρίας ροής. Επιπρόσθετα, μελετήθηκε ο ρόλος του PAR-1 στη διαφοροποίηση των CD34+ κυττάρων προς EPCs, καθώς και στη δημιουργία συζευγμάτων CD34+ κυττάρων/αιμοπεταλίων, με τη μέθοδο της κυτταρομετρίας ροής. Εν συνεχεία, μελετήθηκε η δράση των FXa και θρομβίνης στην ενεργοποίηση προχωρημένης ωρίμανσης ενδοθηλιακών κυττάρων (late-outgrowth endothelial cells, OECs), χρησιμοποιώντας ως δείκτες ενεργοποίησης τη μεμβρανική έκφραση του μορίου προσκόλλησης ICAM-1 και την έκκριση του MCP-1. Πραγματοποιήθηκε μελέτη του ρόλου των rivaroxaban και dabigatran, καθώς και του PAR-1, στην επαγόμενη από τους δύο παράγοντες ενδοθηλιακή ενεργοποίηση. Η παρούσα μελέτη απέδειξε ότι τόσο ο FXa όσο και η θρομβίνη αποτελούν ισχυρούς αγωνιστές της αιμοπεταλιακής ενεργοποίησης και συσσώρευσης, με τον FXa να έχει μία χρονικά καθυστερημένη δράση. Η δράση των δύο παραγόντων βρέθηκε να διαμεσολαβείται από τον PAR-1. Επιπρόσθετα, τα rivaroxaban και dabigatran ανέστειλαν δοσο-εξαρτώμενα την αιμοπεταλιακή συσσώρευση που προκαλείται από τον FXa και τη θρομβίνη, χωρίς να παρουσιάζεται εκλεκτικότητα ως προς το φάρμακο-στόχο. Επιπρόσθετα, ο PAR-1 βρέθηκε να διαμεσολαβεί και τη διαφοροποίηση των CD34+ κυττάρων προς EPCs, αλλά και τη δημιουργία συζευγμάτων CD34+ κυττάρων/αιμοπεταλίων. Ακόμη, η παρούσα μελέτη απέδειξε ότι ο FXa και η θρομβίνη επάγουν την έκφραση του ICAM-1 και την έκκριση του MCP-1 από τα OECs, συμβάντα που διαμεσολαβούνται κυρίως από τον PAR-1. Το vorapaxar δεν ανέστειλε πλήρως την επαγόμενη από τη θρομβίνη έκφραση του ICAM-1 και την έκκριση του MCP-1 από τα OECs, σε αντίθεση με τα HUVECs στα οποία η αναστολή ήταν πλήρης, αποτέλεσμα που προτείνει και τη συμμετοχή του PAR-4 στα OECs. Τα rivaroxaban και dabigatran ανέστειλαν δοσο-εξαρτώμενα την επαγόμενη από τον FXa και τη θρομβίνη, αντίστοιχα, έκφραση του ICAM-1 και την έκκριση του MCP-1. Ένα ενδιαφέρον αποτέλεσμα που παρατηρήθηκε για πρώτη φορά ήταν ότι το rivaroxaban ενίσχυσε την επαγόμενη από τη θρομβίνη έκφραση του ICAM-1 και την έκκριση του MCP-1. Η ενισχυτική δράση του rivaroxaban ανεστάλη από το vorapaxar, γεγονός που υποδηλώνει τη συμμετοχή του PAR-1 στο φαινόμενο αυτό. Συμπερασματικά, η ενεργοποίηση των αιμοπεταλίων και των ενδοθηλιακών κυττάρων από τον FXa και τη θρομβίνη θα μπορούσε να συμβάλει στην αθηροθρόμβωση. Επιπρόσθετα, η δράση των παραγόντων αυτών στα πρόδρομα ενδοθηλιακά κύτταρα θα μπορούσε να είναι ευεργετική για την αναγέννηση του ενδοθηλίου. Παρά το γεγονός ότι η παρούσα μελέτη διερεύνησε εκτενώς ένα ευρύ φάσμα μη αιμοστατικών κυτταρικών δράσεων του FXa και της θρομβίνης, περισσότερες μελέτες απαιτούνται για να διαλευκανθεί πλήρως ο ρόλος των παραγόντων αυτών, αλλά και η συμβολή των φαρμάκων που στοχεύουν τη δράση τους στην αθηροθρόμβωση, την αναγέννηση του ενδοθηλίου και την αγγειογένεση

Regulation of Metabolic Plasticity in Cancer Stem Cells and Implications in Cancer Therapy

Cancer stem cells (CSCs), a subpopulation of tumor cells with self-renewal capacity, have been associated with tumor initiation, progression, and therapy resistance. While the bulk of tumor cells mainly use glycolysis for energy production, CSCs have gained attention for their ability to switch between glycolysis and oxidative phosphorylation, depending on their energy needs and stimuli from their microenvironment. This metabolic plasticity is mediated by signaling pathways that are also implicated in the regulation of CSC properties, such as the Wnt/β-catenin, Notch, and Hippo networks. Two other stemness-associated processes, autophagy and hypoxia, seem to play a role in the metabolic switching of CSCs as well. Importantly, accumulating evidence has linked the metabolic plasticity of CSCs to their increased resistance to treatment. In this review, we summarize the metabolic signatures of CSCs and the pathways that regulate them; we especially highlight research data that demonstrate the metabolic adaptability of these cells and their role in stemness and therapy resistance. As the development of drug resistance is a major challenge for successful cancer treatment, the potential of specific elimination of CSCs through targeting their metabolism is of great interest and it is particularly examined

Anti-Cancer Properties of <i>Stevia rebaudiana</i>; More than a Sweetener

Stevia rebaudiana Bertoni is a perennial shrub from Paraguay that is nowadays widely cultivated, since it is increasingly being utilized as a sugar substitute in various foodstuffs due to its sweetness and minimal caloric content. These properties of the plant’s derivatives have spurred research on their biological activities revealing a multitude of benefits to human health, including antidiabetic, anticariogenic, antioxidant, hypotensive, antihypertensive, antimicrobial, anti-inflammatory and antitumor actions. To our knowledge, no recent reviews have surveyed and reported published work solely on the latter. Consequently, our main objective was to present a concise, literature-based review of the biological actions of stevia derivatives in various tumor types, as studied in in vitro and in vivo models of the disease. With global cancer estimates suggesting a 47% increase in cancer cases by 2040 compared to 2020, the data reviewed in this article should provide a better insight into Stevia rebaudiana and its products as a means of cancer prevention and therapy within the context of a healthy diet

Microalgae based innovative animal fat and proteins replacers for application in functional baked products

Animal fat and proteins, such as milk butter and eggs, are the main ingredients of baked products, and are frequently blamed for food allergies, obesity, cancer and type II diabetes. Therefore, there is an urgent need to replace these ingredients with healthier ones without degrading the organoleptic characteristics of the final product. Microalgae are a great source of protein, minerals and lipids such as omega-3 and omega-6 fatty acids, which are beneficial for human health, offering multiple health benefits such as antioxidant and anti-aging activity. In this study, Chlorella vulgaris microalgae were the selected raw material for the innovative replacers because of their high content in proteins and polyunsaturated fatty acids. The obtained microalgal oil was colour corrected and used to produce brioche-type baked products with 100% animal fat substitution. For protein recovery, the aquatic extract was freeze-dried, producing a dry protein powder that fully substituted the animal protein in the baked products. Finally, the development of bakery products with 100% replacement of both animal fat and protein was achieved. These innovative bakery products showed equal performance to the commercial ones, and even improved organoleptic characteristics according to the sensorial analysis that occurred

Factor Xa and thrombin induce endothelial progenitor cell activation. The effect of direct oral anticoagulants

Factor Xa (FXa) and thrombin exert non-hemostatic cellular actions primarily mediated through protease-activated receptors (PARs). We investigated the effect of FXa and thrombin on human late-outgrowth endothelial cells (OECs), a type of endothelial progenitor cells (EPCs), and on human umbilical vein endothelial cells (HUVECs). The effect of direct oral anticoagulants (DOACs), rivaroxaban and dabigatran, was also studied. The membrane expression of intercellular adhesion molecule-1 (ICAM-1) and the secretion of monocyte chemoattractant protein-1 (MCP-1) were used as cell activation markers. FXa and thrombin increase the ICAM-1 expression and the MCP-1 secretion on both cells, being higher on OECs. Vorapaxar, a specific PAR-1 antagonist, completely inhibits FXa-induced activation of both cells and thrombin-induced HUVEC activation, but only partially thrombin-induced OEC activation. Furthermore, thrombin-receptor activating peptide; TRAP-6, only partially activates OECs. OECs do not membrane-express PAR-4, therefore it may not be involved on thrombin-induced OEC activation. Rivaroxaban and dabigatran inhibit OEC and HUVEC activation by FXa and thrombin, respectively. Rivaroxaban enhances thrombin-induced OEC and HUVEC activation, which is completely inhibited by vorapaxar. The inhibition of OEC and HUVEC activation by vorapaxar and DOACs may represent a new pleiotropic effect of these drugs. The pathophysiological and clinical significance of our findings need to be established

Omics Analysis of Chemoresistant Triple Negative Breast Cancer Cells Reveals Novel Metabolic Vulnerabilities

The emergence of drug resistance in cancer poses the greatest hurdle for successful therapeutic results and is associated with most cancer deaths. In triple negative breast cancer (TNBC), due to the lack of specific therapeutic targets, systemic chemotherapy is at the forefront of treatments, but it only benefits a fraction of patients because of the development of resistance. Cancer cells may possess an innate resistance to chemotherapeutic agents or develop new mechanisms of acquired resistance after long-term drug exposure. Such mechanisms involve an interplay between genetic, epigenetic and metabolic alterations that enable cancer cells to evade therapy. In this work, we generated and characterized a chemoresistant TNBC cell line to be used for the investigation of mechanisms that drive resistance to paclitaxel. Transcriptomic analysis highlighted the important role of metabolic-associated pathways in the resistant cells, prompting us to employ 1H-NMR to explore the metabolome and lipidome of these cells. We identified and described herein numerous metabolites and lipids that were significantly altered in the resistant cells. Integrated analysis of our omics data revealed MSMO1, an intermediate enzyme of cholesterol biosynthesis, as a novel mediator of chemoresistance in TNBC. Overall, our data provide a critical insight into the metabolic adaptations that accompany acquired resistance in TNBC and pinpoint potential new targets

Plasma Brain Natriuretic Peptide Levels in Children with Chronic Kidney Disease and Renal Transplant Recipients: A Single Center Study

Pediatric chronic kidney disease (CKD) patients, as well as kidney transplant patients, are at an increased risk of developing cardiovascular disease. BNP measurement, as a biomarker of cardiovascular risk, has been recommended to this high-risk population. Plasma BNP levels were measured in 56 CKD children in either pre-dialysis stage, hemodialysis (HD) or renal transplant recipients (RTRs) and in 76 sex- and age-matched healthy controls. BNP levels were investigated in HD children, before and after the completion of their HD session. BNP levels in total CKD population, in pre-dialysis stage patients and on HD were significantly higher, compared to the respective controls. HD children had higher BNP levels compared to CKD patients in the pre-dialysis stage. Moreover, post-HD BNP concentration was slightly higher than pre-HD, with the difference being marginally statistically significant. BNP was positively correlated with eGFR, creatinine, cystatin-C and parathormone and negatively with albumin and 25-hydroxyvitamin D. A positive correlation between BNP concentration and the ratio of E/A in pulse-wave Doppler echocardiography was also observed. In conclusion, CKD pediatric patients, mainly those undergoing HD, have high plasma BNP levels which do not decrease after the HD session. This is indicative of a greater risk for future cardiovascular disease