A phase Ib trial of mivavotinib (TAK-659), a dual SYK/FLT3 inhibitor, in patients with relapsed/refractory acute myeloid leukemia

Mivavotinib (TAK-659) is an investigational type 1 tyrosine kinase inhibitor with dual activity against spleen tyrosine kinase (SYK) and FMS-like tyrosine kinase 3 (FLT3). We conducted a phase Ib study to investigate the safety, tolerability, and efficacy of mivavotinib in patients with refractory and/or relapsed (R/R) acute myeloid leukemia (AML). Both daily (QD) and twice daily (BID) dosing regimens were evaluated. A total of 43 patients were enrolled, and there were 5 complete responses (4 with incomplete count recovery). In the QD dosing regimen, the maximum tolerated dose (MTD) was not reached up to 160 mg QD per protocol; 140 mg QD was identified as the recommended phase II dose. In the BID dosing regimen, the MTD was 60 mg BID. Thirty patients (70%) experienced a bleeding event on study; the majority were grades 1 or 2, were resolved without mivavotinib modification, and were not considered related to study treatment. Eleven patients (26%) experienced grade ≥3 bleeding events, which were observed most frequently with the 80 mg BID dose. We conducted platelet aggregation studies to investigate the potential role of mivavotinib-mediated SYK inhibition on platelet function. The bleeding events observed may have been the result of several confounding factors, including AML disease status, associated thrombocytopenia, and high doses of mivavotinib. Overall, these findings indicate that the activity of mivavotinib in R/R AML is modest. Furthermore, any future clinical investigation of this agent should be undertaken with caution, particularly in thrombocytopenic patients, due to the potential bleeding risk of SYK inhibition. ClinicalTrials.gov: NCT02323113

Ex vivo απεικόνιση της ενδομιτωτικής διαδικασίας των μεγακαρυοκυττάρων και διερεύνηση του ρόλου της κυκλίνης Ε στην διαδικασία αυτή

The endomitotic cell cycle in Megakaryocytes, which is comprised by repeated cycles of abrogated mitosis is an integral part of Megakaryocytic development . By utilizing a unique transgenic mouse model where GFP-histone expression is limited to megakaryocytic lineage we demonstrated that endomitosis is different between Megakaryocytes of high and low ploidy. In the low ploidy Megakaryocytes the DNA is clearly segregated into two distinct regions before it rejoins into a single nucleus. In High ploidy Megakaryocytes distinct segregation of DNA is not observed prior to DNA content rejoining into a single nucleus. Our study was the first one to describe the chromosomal dynamics of endomitosis Ex vivo using live imaging.In order to further characterize the endomitotic process efforts to generate transgenic mice that their microtubule network could be visualized were pursued. Several transgenic lines were generated without success and a novel approach is also outlined that may overcome the problems of previous transgenic mice attempts.In addition, based on transgenic mouse model where human Cyclin E1 overexpression is restricted in the megakaryocytic lineage we demonstrate that a higher fraction of bone marrow transgenic Megakaryocytes are in the S phase compared to wild type Megakaryocytes indicating that Cyclin E overexpression is sufficient to drive Megakaryocytes to S phase. Furthermore, a method to rapidly identify homozygotes from heterozygotes in the founder lines of transgenic mice is also described.Polo Like Kinase 3 is a protein that is implicated in the modulation of cell cycle and we detected its expression in Megakaryocytes but experiments using Knock out mice did not reveal an impact in polyploidization.Lysyl Oxidase propeptide (LOX-PP) is a moiety that is is part of the Pre Lysyl oxidase protein and is liberated when mature Lysyl oxidase is produced. It has been shown in multiple studies to exert a powerful anti- proliferation effect in cell lines and here we describe its effect in Megakaryocytic physiology and ploidy. Namely the Lysyl Oxidase Propeptide was able to inhibit Megakaryocytic polyploidization in bone marrow cultures without affecting viability. Importantly, Megakaryocytes expressing human Cyclin E1 were not able the inhibitory effect of LOX-PP.ΠερίληψηΟ ενδομιτωτικος κύκλος των μεγακαρυοκύτταρων, ο οποίος αποτελείται από επαναλαμβανόμενους μη ολοκληρωμενους κύκλους μίτωσης αποτελεί αναπόσπαστο μέρος της μεγακαρυοκυτταρικης ανάπτυξης. Με την χρησιμοποίηση ενός μοναδικου διαγονιδιακόυ μοντέλου ποντικού, οπού η έκφραση της GFP-ιστόνης περιορίζεται στην μεγακαρυοκυτταρική κυταρρικη σειρα αποδείξαμε ότι ενδομίτωση είναι διαφορετική μεταξύ μεγακαρυοκύτταρων υψηλής και χαμηλής πλοειδίας. Στα χαμηλής πλοειδίας μεγακαρυοκύτταρα το DNA είναι σαφώς διαχωριζομενο σε δύο διακριτές περιοχές πριν επανασυσταθει σε ένα ενιαίο πυρήνα. Σε υψηλής πλοειδίας μεγακαρυοκύτταρα διαχωρισμός του DNA σε διακριτές περιοχές δεν παρατηρείται πριν από την επανασύνδεση του περιεχομένου του DNA σε ένα ενιαίο πυρήνα. Η μελέτη μας ήταν ο πρώτη που περιέγραψε την δυναμική των χρωμωσωματτων κατα την διάρκεια της ενδομίτωσης Ex-vivo χρησιμοποιώντας μικροσκοπία ζώντων κυττάρων.Προκειμένου να χαρακτηριστούν περαιτέρω οι διαδικασίες σχετιζόμενες με ενδομιτωση, έγιναν προσπάθειες για δημιουργία διαγονιδιακών ποντικών των οποίων το δίκτυο των μικροσωληνίσκων τους θα μπορούσε να παρατηρηθεί. Αρκετές διαγονιδιακές σειρές παρήχθησαν χωρίς επιτυχία και μια νέα προσέγγιση περιγράφεται που θα μπορούσε να ξεπεράσει τα προβλήματα των προηγούμενων διαγονιδιακων μοντέλων.Επιπλέον, με βάση ενα διαγονιδιακό μοντέλο ποντικού όπου η υπερέκφραση ανθρώπινης κυκλίνης Ε1 περιορίζεται στην μεγακαρυοκυτταρική κυτταρική σειρά έχουμε αποδείξει ότι ένας υψηλότερο κλάσμα των διαγονιδιακων μεγακαρυοκυτταρων του μυελού των οστών στην S φάση σε σύγκριση με το αγρίου τύπου μεγακαρυοκύτταρα υποδεικνύοντας ότι η υπερέκφραση της κυκλίνης Ε είναι επαρκής για να οδηγήσει μεγακαρυοκύτταρα στην S φάση. Περαιτέρω, μια μέθοδος για τον γηγορο εντοπισμό ομοζυγώτων από τους ετεροζυγώτες στις ιδρυτικές γραμμές (founder lines) διαγονιδιακών ποντικών περιγράφεται επίσης.Polo Like Kinase 3 είναι μια πρωτεΐνη που εμπλέκεται στη ρύθμιση του κυτταρικού κύκλου και ανιχνεύσαμε την έκφραση της σε μεγακαρυοκύτταρα, όμως πειράματα χρησιμοποιώντας Knock out ποντικια δεν αποκαλύπτουν μια επίδραση στη πολυπλοειδια.Το προπεπτιδιο της λυσυλ οξειδάσης (LOX-ΡΡ) είναι ενα πρωτεινικο θραύσμα μέρος της πρωτεΐνης Προ- λυσυλ οξειδάσης και απελευθερώνεται όταν η ωριμη λυσυλ οξειδάση παράγεται. Έχει αποδειχθεί σε πολλές μελέτες οτι ασκει μια ισχυρή αντι-αυξητική δραση σε κυτταρικές σειρές και εδώ περιγράφουμε την επίδρασή του στην φυσιολογία και στην πολυπλοειδια των μεγακαρυοκυτταρων. Δηλαδή το προπεπτιδιο της λυσυλ οξειδάσης ηταν ικανο να αναστείλει μεγακαρυοκυτταρική πολυπλοειδια σε καλλιέργειες μυελού των οστών χωρίς να επηρεάζει τη βιωσιμότητα. Ενα σημαντικο εύρημα ηταν οτι μεγακαρυοκύτταρα που εκφράζουν ανθρώπινη κυκλίνη Ε1 δεν ήταν σε θέση το αναστείλουν το αποτέλεσμα του LOX-ΡΡ

Ex-vivo imaging of megakaryocytic endomitosis :differential regulation of chromosomal segregation in low and high ploidy cells

Ο ενδομιτωτικος κυτταρικός κύκλος στα μεγακαρυοκυτταρα (ΜΚ) ο οποίος περιλαμβάνει επαναλαμβανόμενη αντιγραφή του DNA χωρίς κυτταροκίνηση, είναι σημαντικό κομμάτι της ωρίμανσης του ΜΚ. Βάση μελετών ανοσοφθορισμου, είχε υποτεθεί ότι η ρύθμιση της διαδικασίας είναι ίδια για όλα τα ΜΚ ανεξάρτητα πλοειδιας. Πάραυτα, η δυναμική της χρωμοσωμικης κινητικότητας στα ενδομιτωτικα ΜΚ δεν είχε παρατηρηθεί ποτέ in vivo. Χρησιμοποιήσαμε, ένα πρόσφατα κατασκευασμένο στο εργαστήριο μας, διαγονιδιακο μοντέλο ποντικού στο οποίο η ιστονη Η2Β είναι ενωμένη εν σειρά με την πράσινη φθορίζουσα πρωτεΐνη και έχει στοχευόμενη έκφραση στα ΜΚ. Τα ποντίκια αυτά εμφανίζουν έκφραση της GFP και αλληλεπίδραση με το πυρηνικό DNA μόνο στην μεγακαρυωτικη σειρά. Κύτταρα μυελού των οστών, η κύτταρα από καλλιέργειες εμβρυϊκών κύτταρων ήπατος απομονώθηκαν από τα διαγονιδιακα ποντίκια και χρησιμοποιήθηκαν για μικροσκοπία επικεντρωμένη στα ΜΚ. Ένα κύριο ερώτημα ήταν εάν τα κύτταρα ακολουθούν όλα τα σταδία της μίτωσης περιλαμβανόμενου και του σχηματισμού μεσωζωνης. Η ανάλυση μας καταδεικνύει χρωμοσωμικη συμπύκνωση στην πρώιμη μίτωση σε όλα τα ΜΚ κύτταρα ανεξάρτητα πλοειδιας. Στα υψηλής πλοειδιας κύτταρα (>8Μ-16Ν), η συμπύκνωση ακολουθήθηκε από μια δακτυλιοειδή διάταξη των χρωμοσωμάτων και ένα διαχωρισμό άνισων ποσοτήτων DNA που σχημάτισαν περιοχές που έμοιαζαν με μεσοζωνη, χωρίς να ακολουθήσει κυτταροκινηση. Σε αντίθεση, παρατηρήσαμε 8Ν κύτταρα που προήλθαν από 2 ομάδες 4Ν DNA τα οποία αρχικά κινήθηκαν στους αντίθετους πόλους με σχηματισμο καθαρής μεσοζωνης ανάμεσα τους, όπως συμβαίνει στα διπλοειδη κύτταρα, πριν ξαναενωθούν σε ένα πυρήνα απουσία κυτταρικής διαίρεσης. Επίσης, μπορέσαμε να καταγράψουμε τα τελικά σταδία του κατακερματισμού των ΜΚ σε αιμοπετάλια.The endomitotic cell cycle in megakaryocytes (MKs), which involves repeated DNA replication in absence of cytokinesis, is an important part of MK development. Based on immunofluorescence, it has been assumed that the regulation of this process is uniform in all MK cells regardless of ploidy. However, the dynamics of chromosome movement in endomitotic MKs has never been observed in vivo. We utilized, a recently engineered in our laboratory, transgenic mouse model in which histone H2B fused in frame to green fluorescent protein (GFP) was targeted to MKs. These mice display linage specific expression of GFP associated with nuclear DNA. Bone marrow or fetal liver cells isolated from the transgenic mice were subjected to time-lapse microscopy with a focus on MKs. A central inquiry at hand has been whether the cells undergo all steps of mitosis, including a formation of a proper midzone. Our analysis clearly indicated chromosome condensation at early mitosis in all MK cells regardless of ploidy status. In high ploidy MKs (>8N-16N), the condensation was followed by a ring- type alignment of chromosomes and a separation of an uneven amount of DNA to form midzone-like territories, followed by chromosome pulling to one side with no cytokinesis to follow. In contrast, we observed 8N that resulted from two sets of 4N DNA pulling apart to opposite poles with a clear midzone area, as typical of mitotic cells, before re-gathering into one nucleus in absence of cellular division. Furthermore, we were able to monitor and document chromosomal DNA localization during terminal stages of MK fragmentation into platelets

Ex vivo απεικόνιση της ενδομιτωτικής διαδικασίας των μεγακαρυοκυττάρων και διερεύνηση του ρόλου της κυκλίνης Ε στη διαδικασία αυτή

Ο ενδομιτωτικος κύκλος των μεγακαρυοκύτταρων, ο οποίος αποτελείται από επαναλαμβανόμενους μη ολοκληρωμενους κύκλους μίτωσης αποτελεί αναπόσπαστο μέρος της μεγακαρυοκυτταρικης ανάπτυξης. Με την χρησιμοποίηση ενός μοναδικου διαγονιδιακόυ μοντέλου ποντικού, οπού η έκφραση της GFP-ιστόνης περιορίζεται στην μεγακαρυοκυτταρική κυταρρικη σειρα αποδείξαμε ότι ενδομίτωση είναι διαφορετική μεταξύ μεγακαρυοκύτταρων υψηλής και χαμηλής πλοειδίας. Στα χαμηλής πλοειδίας μεγακαρυοκύτταρα το DNA είναι σαφώς διαχωριζομενο σε δύο διακριτές περιοχές πριν επανασυσταθει σε ένα ενιαίο πυρήνα. Σε υψηλής πλοειδίας μεγακαρυοκύτταρα διαχωρισμός του DNA σε διακριτές περιοχές δεν παρατηρείται πριν από την επανασύνδεση του περιεχομένου του DNA σε ένα ενιαίο πυρήνα. Η μελέτη μας ήταν ο πρώτη που περιέγραψε την δυναμική των χρωμωσωματτων κατα την διάρκεια της ενδομίτωσης Ex-vivo χρησιμοποιώντας μικροσκοπία ζώντων κυττάρων. Προκειμένου να χαρακτηριστούν περαιτέρω οι διαδικασίες σχετιζόμενες με ενδομιτωση, έγιναν προσπάθειες για δημιουργία διαγονιδιακών ποντικών των οποίων το δίκτυο των μικροσωληνίσκων τους θα μπορούσε να παρατηρηθεί. Αρκετές διαγονιδιακές σειρές παρήχθησαν χωρίς επιτυχία και μια νέα προσέγγιση περιγράφεται που θα μπορούσε να ξεπεράσει τα προβλήματα των προηγούμενων διαγονιδιακων μοντέλων. Επιπλέον, με βάση ενα διαγονιδιακό μοντέλο ποντικού όπου η υπερέκφραση ανθρώπινης κυκλίνης Ε1 περιορίζεται στην μεγακαρυοκυτταρική κυτταρική σειρά έχουμε αποδείξει ότι ένας υψηλότερο κλάσμα των διαγονιδιακων μεγακαρυοκυτταρων του μυελού των οστών στην S φάση σε σύγκριση με το αγρίου τύπου μεγακαρυοκύτταρα υποδεικνύοντας ότι η υπερέκφραση της κυκλίνης Ε είναι επαρκής για να οδηγήσει μεγακαρυοκύτταρα στην S φάση. Περαιτέρω, μια μέθοδος για τον γηγορο εντοπισμό ομοζυγώτων από τους ετεροζυγώτες στις ιδρυτικές γραμμές (founder lines) διαγονιδιακών ποντικών περιγράφεται επίσης. Polo Like Kinase 3 είναι μια πρωτεΐνη που εμπλέκεται στη ρύθμιση του κυτταρικού κύκλου και ανιχνεύσαμε την έκφραση της σε μεγακαρυοκύτταρα, όμως πειράματα χρησιμοποιώντας Knock out ποντικια δεν αποκαλύπτουν μια επίδραση στη πολυπλοειδια. Το προπεπτιδιο της λυσυλ οξειδάσης (LOX-ΡΡ) είναι ενα πρωτεινικο θραύσμα μέρος της πρωτεΐνης Προ- λυσυλ οξειδάσης και απελευθερώνεται όταν η ωριμη λυσυλ οξειδάση παράγεται. Έχει αποδειχθεί σε πολλές μελέτες οτι ασκει μια ισχυρή αντι-αυξητική δραση σε κυτταρικές σειρές και εδώ περιγράφουμε την επίδρασή του στην φυσιολογία και στην πολυπλοειδια των μεγακαρυοκυτταρων. Δηλαδή το προπεπτιδιο της λυσυλ οξειδάσης ηταν ικανο να αναστείλει μεγακαρυοκυτταρική πολυπλοειδια σε καλλιέργειες μυελού των οστών χωρίς να επηρεάζει τη βιωσιμότητα. Ενα σημαντικο εύρημα ηταν οτι μεγακαρυοκύτταρα που εκφράζουν ανθρώπινη κυκλίνη Ε1 δεν ήταν σε θέση το αναστείλουν το αποτέλεσμα του LOX-ΡΡ.The endomitotic cell cycle in Megakaryocytes, which is comprised by repeated cycles of abrogated mitosis is an integral part of Megakaryocytic development . By utilizing a unique transgenic mouse model where GFP-histone expression is limited to megakaryocytic lineage we demonstrated that endomitosis is different between Megakaryocytes of high and low ploidy. In the low ploidy Megakaryocytes the DNA is clearly segregated into two distinct regions before it rejoins into a single nucleus. In High ploidy Megakaryocytes distinct segregation of DNA is not observed prior to DNA content rejoining into a single nucleus. Our study was the first one to describe the chromosomal dynamics of endomitosis Ex vivo using live imaging. In order to further characterize the endomitotic process efforts to generate transgenic mice that their microtubule network could be visualized were pursued. Several transgenic lines were generated without success and a novel approach is also outlined that may overcome the problems of previous transgenic mice attempts. In addition, based on transgenic mouse model where human Cyclin E1 overexpression is restricted in the megakaryocytic lineage we demonstrate that a higher fraction of bone marrow transgenic Megakaryocytes are in the S phase compared to wild type Megakaryocytes indicating that Cyclin E overexpression is sufficient to drive Megakaryocytes to S phase. Furthermore, a method to rapidly identify homozygotes from heterozygotes in the founder lines of transgenic mice is also described. Polo Like Kinase 3 is a protein that is implicated in the modulation of cell cycle and we detected its expression in Megakaryocytes but experiments using Knock out mice did not reveal an impact in polyploidization. Lysyl Oxidase propeptide (LOX-PP) is a moiety that is is part of the Pre Lysyl oxidase protein and is liberated when mature Lysyl oxidase is produced. It has been shown in multiple studies to exert a powerful anti- proliferation effect in cell lines and here we describe its effect in Megakaryocytic physiology and ploidy. Namely the Lysyl Oxidase Propeptide was able to inhibit Megakaryocytic polyploidization in bone marrow cultures without affecting viability. Importantly, Megakaryocytes expressing human Cyclin E1 were not able the inhibitory effect of LOX-PP

Rates of Infection in Myelofibrosis Patients Treated with Ruxolitinib

Abstract Ruxolitinib is the only JAK 1/2 inhibitor approved by the FDA for the treatment of myelofibrosis (MF). It has been established that ruxolitinib helps improve disease-related constitutional symptoms and splenomegaly. However, studies have shown that ruxolitinib affects several cytokines (IL1, IL6, and TNF-α) and other immune processes (dendritic cells function and T-cell response) and has been linked to increased incidence of opportunistic and non-opportunistic infections. Here we report our experience at the Cleveland Clinic. A total of 50 patients (pts) with MF treated with ruxolitinib were included. The median age of the cohort was 68 years (range: 41-89), 28 of them were males and 22 were females. According to the Dynamic International Prognostic Scoring System (DIPSS), 5 pts had high risk, 23 had intermediate-2 risk, 21 had intermediate-1 risk and 1 had low risk disease. Of these pts, 18 developed infections during their treatment course. Of these infections, 12 were CTCAEv4.0 grade 1-2 and 6 were grade 3-4. Median age of the group was 66 years-old ranging between 50 and 83. Males=9 and females =9. The group was risk-stratified with DIPSS into high risk (N=3), intermediate-2 risk (N=7) and intermediate-1 risk (N=8).The infection started several months after initiation of JAK inhibitor treatment ranging between 2 weeks to 22 months (median of 8 months). Of note, 10 pts had episodes of infections prior to starting ruxolitinib (pneumonia N=5, cellulitis N=3, oral herpes N=2, UTI N=2, genital herpes N=1, Clostiridium difficile diarrhea N=1, viral diarrhea N=1, neutropenic fever N=1, spontaneous bacterial peritonitis N=1 and psoas muscle abscess N=1) . None of the patients had an active infection at the time of starting ruxolitinib. The median total dose given to the pts who developed grade1-2 infection was 20 mg daily, and for those who had grade 3-4 infection it was 15 mg daily. A variety of infections have been reported including pneumonia (N=4), cellulitis\folliculitis (N=4), Clostridium Difficile diarrhea (N=2), URI (N=1), neutropenic fever (N=1), MSSA bacteremia (N=1), herpes zoster activation (N=2), spontaneous bacterial peritonitis (N=1), perineal abscess (N=1) and one pt had a gluteal abscess after a bone marrow biopsy. Most of these infections resolved using oral or topical antibiotics (N=12). However, 6 pts required hospital admissions, and 5 of them required intravenous antibiotics. One of them required admission to the intensive care unit and two others required surgical interventions. Duration of treatment ranged between 1 to 8 weeks (median 2 weeks). Ruxolitinib had to be discontinued due to the severity of the infection in 2 pts, while the others either had a dose reduction or no dose alteration. Two pts required prophylactic antibiotics; one had recurrent SBP despite antimicrobial prophylaxis, while another pt required acyclovir prophylaxis while receiving glucocorticoids with ruxolitinib with no reactivation of Zoster infection. Predisposing factors for infections included a procedure (BMBx N=1), the concurrent use of other immunosuppressive drugs (steroids N=3, other agents N=3) and the prior use of systemic antibiotics in the pts who had C Diff infections (N=2). Only 2 pts had subsequent infections, one had oral herpes and the other had candida esophagitis which required hospitalization and treatment with IV antifungal drugs while on high dose steroids (dexamethasone 4 mg PO twice daily) for immune thrombocytopenia at the time of infection. Though 5 pts had already died at the time of the chart review, none of them died of infectious complications. In summary, infections can occur in patients treated with ruxolitinib but are generally mild. Most infections resolve after an adequate course of oral antimicrobial therapy suggesting that prophylactic antimicrobial agents may not be necessary or cost-effective in the vast majority of MF pts treated with ruxolitinib. Disclosures No relevant conflicts of interest to declare

A Phase I/II Study to Investigate the Safety and Clinical Activity of the Protein Arginine Methyltransferase 5 Inhibitor GSK3326595 in Subjects with Myelodysplastic Syndrome and Acute Myeloid Leukemia

Background Protein arginine methyltransferase 5 (PRMT5) is the primary enzyme responsible for symmetric arginine dimethylation of multiple proteins that impact cell proliferation. Its substrates include proteins involved in mRNA splicing, signal transduction, gene transcription, and DNA repair. PRMT5 overexpression occurs in many cancers and correlates with poor prognosis. GSK3326595 is a potent, specific, and reversible inhibitor of PRMT5 that inhibits proliferation and induces cell death in a broad range of solid and hematologic tumor cell lines. It also exhibits potent anti-tumor activity in vivo in animal models, including in preclinical models of myeloid malignancies. One mechanism of action of GSK3326595 is via inhibition of cellular mRNA splicing and upregulation of tumor suppressor function. Mutations in splicing factors are frequent in myeloid malignancies (including approximately 40% of patients with myelodysplastic syndrome [MDS], and over 60% of patients with chronic myelomonocytic leukemia [CMML]), and further inhibition of mRNA splicing via GSK3326595 may lead to a synthetic lethal phenotype specifically in splicing mutant disease. Study 208809 is the first trial of a PRMT5 inhibitor in participants with myeloid malignancies. Methods Study 208809 is a Phase I/II study to evaluate the safety, tolerability, and clinical activity of GSK3326595 monotherapy in participants with relapsed and refractory MDS, CMML, and hypoproliferative acute myeloid leukemia (AML) that has evolved from an antecedent MDS. Part 1 will identify a tolerated dose and establish preliminary evidence of efficacy in this population. At the end of Part 1, if pre-specified criteria are met, then the study will be expanded with three additional Parts that will be opened in parallel. Part 2A is a Phase II randomized comparison of monotherapy GSK3326595 versus investigator's choice of best available care in participants with relapsed and refractory MDS, CMML, and hypoproliferative AML. Part 2B is a single-arm investigation of safety and efficacy of GSK3326595 plus 5-azacitidine in participants with newly diagnosed high-risk MDS. Part 2C is a single-arm investigation of the safety and efficacy of monotherapy GSK3326595 in participants with relapsed or refractory AML whose tumors harbor mutations in components of the pre-mRNA splicing machinery. All participants enrolled in this study have a diagnosis of MDS, CMML, or AML, with enrollment into each cohort as defined above. Participants are adults with adequate organ function as defined in the protocol. Prior allogeneic transplant is permitted. There are no required biomarkers for enrollment to Parts 1, 2A, and 2B, though central confirmation of pre-mRNA splicing factor mutations will be performed to stratify participants for overall analysis. Enrollment to Part 2C is limited to participants with splicing factor mutations. It is estimated that a maximum of 302 participants will be enrolled in the study, divided as follows: Approximately 41 participants in Part 1, approximately 192 participants in Part 2A, approximately 41 participants in Part 2B, and approximately 28 participants in Part 2C. In Part 1, the primary endpoint is clinical benefit rate, as defined as the percentage of participants achieving a complete remission, complete marrow remission, partial remission (PR), stable disease lasting at least 8 weeks, or hematologic improvement, as per standard criteria. In Part 2A, the primary endpoint is overall survival. In Part 2B and Part 2C, the primary endpoint is overall response rate (ORR), defined as the percentage of participants achieving a PR or better. Samples are collected to evaluate symmetric dimethylated arginine (SDMA), the enzymatic product of PRMT5. This has been demonstrated to be a pharmacodynamic marker of PRMT5 inhibition in plasma and tumor tissue. In addition, participants will be stratified based on the presence or absence of spliceosome mutations and analyzed separately to evaluate the effect of these mutations on clinical activity. As of 1 August 2019, recruitment is ongoing across six centers in the United States and Canada; ten participants have been enrolled, all into Part 1. ClinicalTrials.gov identifier: NCT03614728 Study is funded by GlaxoSmithKline Disclosures Watts: Takeda: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Bradley:AbbVie: Other: Advisory Board. Brunner:Novartis: Research Funding; Jazz Pharma: Membership on an entity's Board of Directors or advisory committees; Forty Seven Inc: Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding. Minden:Trillium Therapetuics: Other: licensing agreement. Papadantonakis:Agios: Consultancy, Honoraria. Abedin:Actinium Pharmaceuticals: Research Funding; Pfizer Inc: Research Funding; Helsinn Healthcare: Research Funding; Agios: Honoraria; Jazz Pharmaceuticals: Honoraria. Baines:GlaxoSmithKline: Employment, Equity Ownership. Barbash:GlaxoSmithKline: Employment, Equity Ownership, Patents & Royalties, Research Funding. Gorman:GlaxoSmithKline: Employment, Equity Ownership. Kremer:GlaxoSmithKline: Employment, Equity Ownership. Borthakur:Cantargia AB: Research Funding; Eisai: Research Funding; Tetralogic Pharmaceuticals: Research Funding; Argenx: Membership on an entity's Board of Directors or advisory committees; FTC Therapeutics: Membership on an entity's Board of Directors or advisory committees; BioTheryX: Membership on an entity's Board of Directors or advisory committees; Xbiotech USA: Research Funding; Novartis: Research Funding; Oncoceutics: Research Funding; Oncoceutics, Inc.: Research Funding; PTC Therapeutics: Consultancy; BioLine Rx: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Agensys: Research Funding; AstraZeneca: Research Funding; Bayer Healthcare AG: Research Funding; BMS: Research Funding; Eli Lilly and Co.: Research Funding; NKarta: Consultancy; Cyclacel: Research Funding; GSK: Research Funding; Janssen: Research Funding; Incyte: Research Funding; AbbVie: Research Funding; Merck: Research Funding; Arvinas: Research Funding; Polaris: Research Funding; Strategia Therapeutics: Research Funding

Phytoextraction and phytoexcretion of Cd by the leaves of Tamarix smyrnensis growing on contaminated non-saline and saline soils

Δημοσίευση σε επιστημονικό περιοδικόSummarization: Phytoremediation and more specifically phytoextraction, is an alternative restoration strategy for the clean up of heavy metal contaminated soils. Phytoextraction can only be successful if suitable plant species colonize the contaminated area, extract the toxic substances and accumulate them in their above ground tissues. In this study, the salt cedar Tamarix smyrnensis that is a widespread salt-tolerant plant in the Mediterranean region has been investigated. A pot experiment is conducted with T. smyrnensis grown in polluted soil with 16 ppm of cadmium and at three different salt concentrations (0.0, 0.5, 3.0% NaCl) for a 10-week period. It took place in an open-air area with natural light, at ambient temperature and humidity in an effort to keep the plants under conditions as similar as possible to those in the field. However, care was taken not to let them be rained on. Temperature ranged from 19 to 50 °C with 33 and 21 °C being the average day and night temperature, respectively. Humidity ranged from 28% to 87% with a 13–14 h photoperiod. The specific aims of this work are to investigate the accumulation of cadmium via root uptake at different saline conditions and cadmium excretion through salt glands on the surface of the leaves as a probable detoxification mechanism of the plant. Furthermore, measurements of chlorophyll content, biomass, and shoot length are used to evaluate the potential of the plant for the removal of cadmium from contaminated saline and non-saline soils. The experimental data suggest that increased soil salinity results in an increase of the cadmium uptake by T. smyrnensis. Analysis of white salt crystals taken from glandular tissue confirmed the fact that this plant excretes cadmium through its salt glands on the surface of the leaves as a possible detoxification mechanism in order to resist metal toxicity. Excreted cadmium is again released into the environment and it is redeposited on the top soil. Furthermore, increased salinity results in an increased excretion of the metal on Tamarix leaf surface. The presence of metals usually affects negatively the plant health, but T. smyrnensis developed no visible signs of metal toxicity, only salt toxicity symptoms were observed. Cadmium usually decreases the chlorophyll content in plants; however, the amount of photosynthetic pigments of T. smyrnensis was found not to be affected. All the above points to the potential of T. smyrnensis for use in phytoremediation with the metal secretion from the leaves being a unique advantage that may change current phytoextraction practices.Presented on: Environmental Researc

Prognostic impact of incomplete hematologic count recovery and minimal residual disease on outcome in adult acute lymphoblastic leukemia at the time of second complete response

Outcomes of relapsed adult acute lymphoblastic leukemia (ALL) have improved over time with the introduction of new therapies as well as better supportive care. However, there is still a need for easy-to-use and accurate prognostic tools for patients in first relapse. Whether complete response (CR) with incomplete count recovery (CRh) can be grouped with CR in relapsed ALL trials has not been formally studied. We analyzed 106 ALL patients at first relapse who were treated at three academic centers and achieved CR/CRh. White blood cell count at initial diagnosis and receiving hematopoietic cell transplant (HCT) were independent predictors of overall survival after relapse, while minimal residual disease (MRD) positivity and performance of HCT were predictors of relapse free survival (RFS). Patients who achieved MRD negativity and underwent HCT had the best outcomes. Our results suggest that MRD is a more powerful predictor of outcome than CRh