The isoflavone metabolite 6-methoxyequol inhibits angiogenesis and suppresses tumor growth

WOS:000307348200001Peer reviewe

Metabolic Fingerprinting Links Oncogenic PIK3CA with Enhanced Arachidonic Acid-Derived Eicosanoids.

Oncogenic transformation is associated with profound changes in cellular metabolism, but whether tracking these can improve disease stratification or influence therapy decision-making is largely unknown. Using the iKnife to sample the aerosol of cauterized specimens, we demonstrate a new mode of real-time diagnosis, coupling metabolic phenotype to mutant PIK3CA genotype. Oncogenic PIK3CA results in an increase in arachidonic acid and a concomitant overproduction of eicosanoids, acting to promote cell proliferation beyond a cell-autonomous manner. Mechanistically, mutant PIK3CA drives a multimodal signaling network involving mTORC2-PKCζ-mediated activation of the calcium-dependent phospholipase A2 (cPLA2). Notably, inhibiting cPLA2 synergizes with fatty acid-free diet to restore immunogenicity and selectively reduce mutant PIK3CA-induced tumorigenicity. Besides highlighting the potential for metabolic phenotyping in stratified medicine, this study reveals an important role for activated PI3K signaling in regulating arachidonic acid metabolism, uncovering a targetable metabolic vulnerability that largely depends on dietary fat restriction. VIDEO ABSTRACT

Genetic prediction of ICU hospitalization and mortality in COVID-19 patients using artificial neural networks

There is an unmet need of models for early prediction of morbidity and mortality of Coronavirus disease-19 (COVID-19). We aimed to a) identify complement-related genetic variants associated with the clinical outcomes of ICU hospitalization and death, b) develop an artificial neural network (ANN) predicting these outcomes and c) validate whether complement-related variants are associated with an impaired complement phenotype. We prospectively recruited consecutive adult patients of Caucasian origin, hospitalized due to COVID-19. Through targeted next-generation sequencing, we identified variants in complement factor H/CFH, CFB, CFH-related, CFD, CD55, C3, C5, CFI, CD46, thrombomodulin/THBD, and A Disintegrin and Metalloproteinase with Thrombospondin motifs (ADAMTS13). Among 381 variants in 133 patients, we identified 5 critical variants associated with severe COVID-19: rs2547438 (C3), rs2250656 (C3), rs1042580 (THBD), rs800292 (CFH) and rs414628 (CFHR1). Using age, gender and presence or absence of each variant, we developed an ANN predicting morbidity and mortality in 89.47% of the examined population. Furthermore, THBD and C3a levels were significantly increased in severe COVID-19 patients and those harbouring relevant variants. Thus, we reveal for the first time an ANN accurately predicting ICU hospitalization and death in COVID-19 patients, based on genetic variants in complement genes, age and gender. Importantly, we confirm that genetic dysregulation is associated with impaired complement phenotype.- Pfizer Pharmaceuticals(undefined

VEGF (Vascular Endothelial Growth Factor) regulated genes

VEGF is the key modulator of normal vessel generation being also involved in the pathogenesis of angiogenic diseases, such as cancer. Therefore, unraveling its signaling cascades in endothelial cell might provide molecular targets for the development of anti-angiogenic therapies. The present thesis was based on the observation, by cDNA microarrays, that two genes participating in the unfolded protein response (UPR) of ER, HERPUD1 and DNAJB9, were transcriptionally activated by VEGF. The over-expression of the two genes was specific for VEGF not being induced by FGF2, another potent angiogenic factor. Additional screening revealed that VEGF induces not only the HERPUD1 and DNAJB9 genes, but also the majority of the genes regulated by the three UPR branches (IRE1, ATF6 και PERK). The generalized transcriptional activation of UPR genes was not caused by increased load of proteins in the ER lumen due to activation of the secretory pathway by VEGF. This conclusion was based on several experimental data. First, inhibition of protein synthesis by cycloheximide exhibited a minor impact on the transcriptional activation of the HERPUD1 and DNAJB9 genes by VEGF. Secondly, VEGF leads to a rapid (within 15-30 min) but short-term activation of the three branches of UPR (IRE1, ATF6 and PERK), contrary to Tunicamicin (Tm), a N-linked glycosylation inhibitor that leads to ER overload with misfolded proteins, that induces activation of the IRE1, ATF6 and PERK pathways in a delayed and long-term manner. Finally, using a series of specific inhibitors of VEGF pathways and siRNA gene silencing, we have identified that the PLCγ pathway of VEGF was responsible for the activation of the tree UPR branches. The mechanism by which the PLCγ pathway activates IRE1, ATF6 and PERK is still unknown however, our data indicate that is Ca2+-independent. Activation of the three UPR pathways of ER appeared to be critical for the VEGF-induced endothelial cell survival. In particular, silencing of the ATF6 and eIF2a genes reduced the VEGF-induced survival of endothelial cells by 50%. Indeed, activation of the ER-mediated cascades by VEGF was crucial for its anti-apoptotic effect on endothelial cells. VEGF-induced phosphorylation of Akt by the PI3K pathway required concomitantly active PLCγ-ER-ATF6/PERK and PLCγ-IP3-ER-Ca2+-calmodulin-CaMKII cascades. Interestingly, VEGF administration to endothelial cells was associated with undetected levels of the pro-apoptotic protein CHOP despite the transcriptional activation of its gene via the PERK/ATF4 pathway. This is compatible with previous studies reporting that the mRNA and protein of CHOP are unstable being rapidly degraded during mild (adaptive) UPR. Thus, VEGF incorporates the ER-dependent cascades in its signaling machinery to achieve a maximal anti-apoptotic effect on endothelial cells. This study contributes novel knowledge in the signal transduction of VEGF and elucidates unknown aspects of the ER function in cell homeostasis. ER emerges as key component of the signal transducing machinery of VEGF in endothelial cells as the latter activates the three UPR branches of ER through the PLCγ pathway. We named the activation of IRE1, ATF6 and PERK (and their following transcriptional induction) by signaling cascades of extracellular ligands as Extracellular Signaling Response (ESR) of ER to distinguish it from activation due to overloading of ER with unfolded proteins (UPR).O VEGF είναι ο κύριος ρυθμιστής της δημιουργίας φυσιολογικών αγγείων, αλλά επίσης εμπλέκεται στην παθογένεση των αγγειογενετικών νόσων, όπως ο καρκίνος. Έτσι, η διερεύνηση της μεταγωγής του σήματος του αναμένεται να εντοπίσει νέους μοριακούς στόχους για την ανάπτυξη αντι-αγγειογενετικών θεραπειών. Η παρούσα διατριβή βασίστηκε στην παρατήρηση, με μικροσυστοιχίες cDNA, ότι ο VEGF ενεργοποιεί μεταγραφικά τα γονίδια HERPUD1 και DNAJB9, τα οποία συμμετέχουν στην απόκριση του ΕΔ στην παρουσία μη αναδιπλωμένων πρωτεϊνών στον αυλό του (Unfolded protein Response, UPR). Η υπερέκφραση των δύο αυτών γονιδίων από τον VEGF ήταν ειδική και δεν παρατηρήθηκε μετά από χορήγηση FGF2, ενός άλλου ισχυρού αγγειογενετικού παράγοντα. Παραπέρα μελέτη αποκάλυψε ότι ο VEGF δεν επάγει μόνο τα γονίδια HERPUD1 και DNAJB9, αλλά επίσης την πλειοψηφία των γονιδίων που ρυθμίζονται και από τους τρεις βραχίονες της UPR (IRE1, ATF6 και PERK). Η γενικευμένη αυτή ενεργοποίηση των γονιδίων της UPR δεν προκλήθηκε από αυξημένα φορτία πρωτεϊνών στον αυλό του ΕΔ εξαιτίας της ενεργοποίησης του εκκριτικού μονοπατιού από τον VEGF. Το συμπέρασμα αυτό βασίστηκε στα εξής δεδομένα. Πρώτον, παρά την αναστολή της πρωτεϊνοσύνθεσης με κυκλοεξιμίδιο, η προσθήκη VEGF συνέχισε να επάγει μεταγραφικά, αν και σε μικρότερο βαθμό, τα γονίδια HERPUD1 και DNAJB. Δεύτερον, η ενεργοποίηση και των τριών μονοπατιών της UPR (IRE1, ATF6 και PERK) από τον VEGF ήταν ταχύτατη (εντός 15-30 λεπτών) και εξασθένησε γρήγορα. Αντίθετα, η προσθήκη του αναστολέα της N-γλυκοσυλίωσης Tunicamycin (Tm), η οποία υπερφορτώνει το ΕΔ με πρωτεΐνες λανθασμένης διαμόρφωσης, προκάλεσε την ενεργοποίηση των τριών μονοπατιών της UPR σε αργότερο χρονικό διάστημα (μερικές ώρες) και για μακρό χρονικό διάστημα. Τέλος, με τη χρήση ειδικών αναστολέων κινασών και αποσιώπηση γονιδίων με siRNA, δείξαμε πως o VEGF επάγει την UPR διαμέσου του μονοπατιού της PLCγ. Αν και ο μηχανισμός ενεργοποίησης των βραχιόνων της UPR από το μονοπάτι της PLCγ παραμένει άγνωστος, τα δεδομένα μας δείχνουν ότι δεν εξαρτάται από τη διακύμανση της συγκέντρωσης του ασβεστίου στο κυτταρόπλασμα και το ΕΔ.Η ενεργοποίηση των τριών βραχιόνων της UPR φαίνεται να παίζει κρίσιμο ρόλο στην επαγωγή της επιβίωσης που προκαλεί ο VEGF στα ενδοθηλιακά κύτταρα. Συγκεκριμένα, η αποσιώπηση των ATF6 και eIF2a γονιδίων μείωσε κατά 50% την επαγωγή της επιβίωσης των ενδοθηλιακών κυττάρων από τον VEGF. Ουσιαστικά, η ενεργοποίηση αμφοτέρων των μονοπατιών που διαμεσολαβούνται από το ΕΔ είναι κομβικής σημασίας για την αντι-αποπτωτική δράση του VEGF στα ενδοθηλιακά κύτταρα. Πράγματι, η φωσφορυλίωση της Akt από το μονοπάτι της PI3K εξαρτάται από την ταυτόχρονη ενεργοποίηση των PLCγ-ER-ATF6/PERK και PLCγ-IP3-ER-Ca2+-calmodulin-CaMKII μονοπατιών. Παράλληλα, η χορήγηση VEGF στα ενδοθηλιακά κύτταρα οδηγεί σε μη ανιχνεύσιμα επίπεδα της προ-αποπτωτικής πρωτεΐνης CHOP, παρά το γεγονός ότι γονίδιο της CHOP ενεργοποιείται μεταγραφικά, κυρίως από το μονοπάτι PERK/ATF4. Η παρατήρηση αυτή είναι συμβατή με προηγούμενη μελέτη όπου το mRNA και η πρωτεΐνη της CHOP είναι ασταθή και αποικοδομούνται ταχύτατα κατά τη διάρκεια ήπιας UPR. Φαίνεται, λοιπόν, ότι η ενσωμάτωση των μονοπατιών του ΕΔ στους μηχανισμούς μεταγωγής του σήματος του VEGF μεγιστοποιεί την αντι-αποπτωτική δράση του στα ενδοθηλιακά κύτταρα. Η παρούσα μελέτη προσθέτει νέα γνώση όσον αφορά τη μεταγωγή του σήματος από τον VEGF και φωτίζει άγνωστες πτυχές του ρόλου του ΕΔ στην ομοιοστασία του κυττάρου. Τα πειραματικά δεδομένα υποδεικνύουν ότι ο VEGF, διαμέσου της PLCγ, ενεργοποιεί διαδικασίες του ΕΔ, όπως η UPR, οι οποίες εντάσσονται στο μηχανισμό της μεταγωγής σήματος του VEGF συμμετέχοντας στις δράσεις του τελευταίου στα ενδοθηλιακά κύτταρα. Έτσι, ονομάσαμε την ενεργοποίηση των IRE1, ATF6 και PERK του ΕΔ (και της επακόλουθης μεταγραφικής επαγωγής) από τα μονοπάτια σηματοδότησης εξωκυτταρικών προσδεμάτων ως «Extracellular Signaling Response (ESR)», για να τη διαφοροποιήσουμε από την ενεργοποίηση διαμέσου υπερφόρτωσης του ΕΔ με μη αναδιπλωμένες πρωτεΐνες (Unfolded Protein Response, UPR)

Direct Binding of Bcl‑2 Family Proteins by Quercetin Triggers Its Pro-Apoptotic Activity

Bcl-2 family proteins are important regulators of apoptosis and its antiapoptotic members, which are overexpressed in many types of cancer, are of high prognostic significance, establishing them as attractive therapeutic targets. Quercetin, a natural flavonoid, has drawn much attention because it exerts anticancer effects, while sparing normal cells. A multidisciplinary approach has been employed herein, in an effort to reveal its mode of action including dose–response antiproliferative activity and induced apoptosis effect, biochemical and physicochemical assays, and computational calculations. It may be concluded that, quercetin binds directly to the BH3 domain of Bcl-2 and Bcl-xL proteins, thereby inhibiting their activity and promoting cancer cell apoptosis

Genetic prediction of ICU hospitalization and mortality in COVID-19 patients using artificial neural networks

There is an unmet need of models for early prediction of morbidity and mortality of Coronavirus disease-19 (COVID-19). We aimed to a) identify complement-related genetic variants associated with the clinical outcomes of ICU hospitalization and death, b) develop an artificial neural network (ANN) predicting these outcomes and c) validate whether complement-related variants are associated with an impaired complement phenotype. We prospectively recruited consecutive adult patients of Caucasian origin, hospitalized due to COVID-19. Through targeted next-generation sequencing, we identified variants in complement factor H/CFH, CFB, CFH-related, CFD, CD55, C3, C5, CFI, CD46, thrombomodulin/THBD, and A Disintegrin and Metalloproteinase with Thrombospondin motifs (ADAMTS13). Among 381 variants in 133 patients, we identified 5 critical variants associated with severe COVID-19: rs2547438 (C3), rs2250656 (C3), rs1042580 (THBD), rs800292 (CFH) and rs414628 (CFHR1). Using age, gender and presence or absence of each variant, we developed an ANN predicting morbidity and mortality in 89.47% of the examined population. Furthermore, THBD and C3a levels were significantly increased in severe COVID-19 patients and those harbouring relevant variants. Thus, we reveal for the first time an ANN accurately predicting ICU hospitalization and death in COVID-19 patients, based on genetic variants in complement genes, age and gender. Importantly, we confirm that genetic dysregulation is associated with impaired complement phenotype

Vitamin B5 supports MYC oncogenic metabolism and tumor progression in breast cancer.

Acknowledgements: This work was supported by the Francis Crick Institute, which receives its core funding from Cancer Research UK, the UK Medical Research Council and the Wellcome Trust, FC001223 (M.Y.) and FC0010060 (L.P.S.C.); by the CRUK Grand Challenge Award 2015 C57633/A25043 (J.B., M.Y., Z.T., G.P., S.B. and R.J.A.G.). The work was also supported by UK Research and Innovation (MR/W012030/1) and The Institute of Cancer Research (G.P.). For the purpose of Open Access, the author has applied a CC BY public copyright license to any Author Accepted Manuscript version arising from this submission. We thank all animal technicians from the Francis Crick Biological Research Facility for their dedicated work.Tumors are intrinsically heterogeneous and it is well established that this directs their evolution, hinders their classification and frustrates therapy1-3. Consequently, spatially resolved omics-level analyses are gaining traction4-9. Despite considerable therapeutic interest, tumor metabolism has been lagging behind this development and there is a paucity of data regarding its spatial organization. To address this shortcoming, we set out to study the local metabolic effects of the oncogene c-MYC, a pleiotropic transcription factor that accumulates with tumor progression and influences metabolism10,11. Through correlative mass spectrometry imaging, we show that pantothenic acid (vitamin B5) associates with MYC-high areas within both human and murine mammary tumors, where its conversion to coenzyme A fuels Krebs cycle activity. Mechanistically, we show that this is accomplished by MYC-mediated upregulation of its multivitamin transporter SLC5A6. Notably, we show that SLC5A6 over-expression alone can induce increased cell growth and a shift toward biosynthesis, whereas conversely, dietary restriction of pantothenic acid leads to a reversal of many MYC-mediated metabolic changes and results in hampered tumor growth. Our work thus establishes the availability of vitamins and cofactors as a potential bottleneck in tumor progression, which can be exploited therapeutically. Overall, we show that a spatial understanding of local metabolism facilitates the identification of clinically relevant, tractable metabolic targets