W fibrosis and impaired haematopoiesis resulting in serious anaemia, enormous splenomegaly
W fibrosis and impaired haematopoiesis resulting in severe anaemia, huge splenomegaly and extramedullary haematopoiesis together with the presence of severe constitutional symptoms. At present only one drug, ruxolitinib, has been approved mainly determined by its capability to lower splenomegaly and improvement of disease-related symptoms.four,five Therefore, agents with activity in this group of malignancies are required. COX-1 manufacturer plitidepsin (Aplidin) is often a cyclic depsipeptide initially isolated in the Mediterranean tunicate Aplidium albicans and presently produced by chemical synthesis.six Plitidepsin was evaluated within a murine model of myelofibrosis (MF), the Gata-1(low) mice.7 Therapy with plitidepsin improved the platelet count in blood and marrow cellularity in the femur, and reduced the vessel density and expression of transforming GLUT4 Compound growth factor-beta, vascular endothelial development element and thrombopoietin.eight,9 As a result, plitidepsin ameliorated a few of the traits from the myelofibroticphenotype expressed by Gata-1(low) mice. In particular, the observed inhibition of transforming growth factor-beta and vascular endothelial development aspect expression, associated with decreased microvessel density, recommended a attainable activity of plitidepsin in human MF, where levels of those two cytokines are abnormally elevated.8,9 The aforementioned information supported this drug as candidate for clinical evaluation in MF. Consequently, an exploratory phase II clinical trial was created to evaluate the efficacy and safety of plitidepsin in sufferers with PMF, post-PV MF or post-ET MF (ClinicalTrials.gov identifier: NCT01149681). We also report herein new preclinical information obtained in cellular models of MF, such as cell lines and principal patients’ cells. Components AND Approaches Preclinical studiesPlitidepsin was supplied by PharmaMar, dissolved in DMSO and stored in aliquots at – 20 . For in vitro studies, we used the following human cell lines: HEL, UKE-1 and SET2 (JAK2V617F mutated) and K562 (BCRABL1 mutated), as well as the murine BaF3 cell lines overexpressing the wild-type or V617F-mutated JAK2. Primary cells were obtained from individuals with PMF, diagnosed according to the 2008 Globe Well being Organization (WHO) criteria, under a protocol authorized by the Institutional Overview Board of Azienda Ospedaliera-Universitaria Careggi and soon after acquiring an informed consent. Standard CD34 cells have been obtained from healthy donors for1 Division of Hematology, Division of Medicine, Mayo Clinic, Rochester, MN, USA; 2Department of Experimental and Clinical Medicine, University of Florence, Careggi, Firenze, Italy and 3PharmaMar, Clinical R D Department, Colmenar Viejo, Madrid, Spain. Correspondence: Dr A Pardanani, Division of Hematology, Department of Medicine, Department of Hematology, Mayo Clinic Cancer Center, 200 1st Street South West, Rochester 55905, MN, USA or Professor AM Vannucchi, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, Florence 50134, Italy. E-mail: pardanani.animeshmayo.edu or amvannucchiunifi.it Received 9 December 2014; revised 9 January 2015; accepted 21 JanuaryPhase II study of plitidepsin in myelofibrosis A Pardanani et altransplantation purposes who agreed to donate the excess CD34 cells, immediately after providing an informed consent. Research was carried out based on the principles in the Declaration of Helsinki. The drug-induced inhibition of cell growth by plitidepsin in human and mouse cell lines have been measured by both a short-te.