1
|
Andersen CL, Mortensen NB, Klausen TW, Vestergaard H, Bjerrum OW, Hasselbalch HC. A phase II study of vorinostat (MK-0683) in patients with primary myelofibrosis and post-polycythemia vera myelofibrosis. Haematologica 2014; 99:e5-7. [PMID: 24425692 DOI: 10.3324/haematol.2013.096669] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
|
2
|
|
3
|
Abstract
The discovery of the JAK2V617F mutation in most patients with Ph-negative myeloproliferative neoplasms has led to the development of JAK2 kinase inhibitors. However, JAK2 inhibitor therapy has shown limited efficacy and dose-limiting hematopoietic toxicities in clinical trials. In the present study, we describe the effects of vorinostat, a small-molecule inhibitor of histone deacetylase, against cells expressing JAK2V617F and in an animal model of polycythemia vera (PV). We found that vorinostat markedly inhibited proliferation and induced apoptosis in cells expressing JAK2V617F. In addition, vorinostat significantly inhibited JAK2V617F-expressing mouse and human PV hematopoietic progenitors. Biochemical analyses revealed significant inhibition of phosphorylation of JAK2, Stat5, Stat3, Akt, and Erk1/2 in vorinostat-treated, JAK2V617F-expressing human erythroleukemia (HEL) cells. Expression of JAK2V617F and several other genes, including GATA1, KLF1, FOG1, SCL, C/EPBα, PU.1, and NF-E2, was significantly down-regulated, whereas the expression of SOCS1 and SOCS3 was up-regulated by vorinostat treatment. More importantly, we observed that vorinostat treatment normalized the peripheral blood counts and markedly reduced splenomegaly in Jak2V617F knock-in mice compared with placebo treatment. Vorinostat treatment also decreased the mutant allele burden in mice. Our results suggest that vorinostat may have therapeutic potential for the treatment of PV and other JAK2V617F-associated myeloproliferative neoplasms.
Collapse
|
4
|
Reddy MM, Deshpande A, Sattler M. Targeting JAK2 in the therapy of myeloproliferative neoplasms. Expert Opin Ther Targets 2012; 16:313-24. [PMID: 22339244 DOI: 10.1517/14728222.2012.662956] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Myeloproliferative neoplasms (MPNs) are a group of stem cell diseases, including polycythemia vera, essential thrombocythemia and primary myelofibrosis. Currently, there is no curative therapy for these diseases other than bone marrow transplant; therefore there is an apparent need for palliative treatment. MPNs are frequently associated with activating mutations in JAK2; small-molecule drugs targeting this molecule have entered clinical trials. AREAS COVERED In this review novel JAK2 inhibitors are discussed and alternative approaches to inhibiting their transforming potential are highlighted. Current clinical approaches do not only aim at blocking JAK2 activity, but also at reducing its stability and expression are highlighted, including inhibition of heat shock protein 90 (HSP90) and deacetylases (DAC) have the potential to significantly enhance the efficacy of JAK2 inhibitors. EXPERT OPINION Preliminary results from clinical trials indicate the feasibility and efficacy of JAK2-targeted approaches. However, JAK2 inhibitor treatment is limited by dose-dependent toxicity and combination treatment might be required. The discovery of JAK2 mutations that cause secondary resistance in vitro would further highlight the need for the development of next-generation JAK2 inhibitors and novel synergistic approaches.
Collapse
Affiliation(s)
- Mamatha M Reddy
- Dana-Farber Cancer Institute, Department of Medical Oncology, Boston, MA 02215, USA
| | | | | |
Collapse
|
5
|
Epigenetic abnormalities in myeloproliferative neoplasms: a target for novel therapeutic strategies. Clin Epigenetics 2011; 2:197-212. [PMID: 22704337 PMCID: PMC3365400 DOI: 10.1007/s13148-011-0050-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Accepted: 06/29/2011] [Indexed: 12/13/2022] Open
Abstract
The myeloproliferative neoplasms (MPNs) are a group of clonal hematological malignancies characterized by a hypercellular bone marrow and a tendency to develop thrombotic complications and to evolve to myelofibrosis and acute leukemia. Unlike chronic myelogenous leukemia, where a single disease-initiating genetic event has been identified, a more complicated series of genetic mutations appear to be responsible for the BCR-ABL1-negative MPNs which include polycythemia vera, essential thrombocythemia, and primary myelofibrosis. Recent studies have revealed a number of epigenetic alterations that also likely contribute to disease pathogenesis and determine clinical outcome. Increasing evidence indicates that alterations in DNA methylation, histone modification, and microRNA expression patterns can collectively influence gene expression and potentially contribute to MPN pathogenesis. Examples include mutations in genes encoding proteins that modify chromatin structure (EZH2, ASXL1, IDH1/2, JAK2V617F, and IKZF1) as well as epigenetic modification of genes critical for cell proliferation and survival (suppressors of cytokine signaling, polycythemia rubra vera-1, CXC chemokine receptor 4, and histone deacetylase (HDAC)). These epigenetic lesions serve as novel targets for experimental therapeutic interventions. Clinical trials are currently underway evaluating HDAC inhibitors and DNA methyltransferase inhibitors for the treatment of patients with MPNs.
Collapse
|
6
|
Mithraprabhu S, Grigoriadis G, Khong T, Spencer A. Deactylase inhibition in myeloproliferative neoplasms. Invest New Drugs 2010; 28 Suppl 1:S50-7. [PMID: 21127942 PMCID: PMC3003795 DOI: 10.1007/s10637-010-9590-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 10/28/2010] [Indexed: 12/02/2022]
Abstract
Myeloproliferative neoplasms (MPN) are clonal haemopoietic progenitor cell disorders characterized by the proliferation of one or more of the haemopoietic lineages (myeloid, erythroid and/or megakaryocytic). The MPNs include eight haematological disorders: chronic myelogenous leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET), primary myelofibrosis (PMF), systemic mastocytosis (SM), chronic eosinophilic leukemia, not otherwise specified (CEL, NOS), chronic neutrophilic leukemia (CNL), and unclassifiable MPN (MPN, U). Therapeutic interventions for MPNs include the use of tyrosine kinase inhibitors (TKIs) for BCR-ABL1(+) CML and JAK2 inhibitors for PV, ET and PMF. Histone deacetylase inhibitors (HDACi) are a novel class of drugs capable of altering the acetylation status of both histone and non-histone proteins, thereby affecting a repertoire of cellular functions in neoplastic cells including proliferation, differentiation, immune responses, angiogenesis and survival. Preliminary studies indicate that HDACi when used in combination with tyrosine kinase or JAK2 inhibitors may overcome resistance to the latter agents and enhance the pro-apoptotic effects on MPN cells. This review provides a review of pre-clinical and clinical studies that have explored the use of HDACi as potential therapeutics for MPNs.
Collapse
Affiliation(s)
- Sridurga Mithraprabhu
- Myeloma Research Group, Australian Centre for Blood Diseases, Alfred Hospital/Monash University, Commercial Road, Melbourne, Victoria 3004 Australia
| | - George Grigoriadis
- Myeloma Research Group, Australian Centre for Blood Diseases, Alfred Hospital/Monash University, Commercial Road, Melbourne, Victoria 3004 Australia
- Burnet Institute, Commercial Road, Melbourne, Victoria 3004 Australia
- Department of Clinical Haematology, Central Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria 3004 Australia
| | - Tiffany Khong
- Myeloma Research Group, Australian Centre for Blood Diseases, Alfred Hospital/Monash University, Commercial Road, Melbourne, Victoria 3004 Australia
| | - Andrew Spencer
- Myeloma Research Group, Australian Centre for Blood Diseases, Alfred Hospital/Monash University, Commercial Road, Melbourne, Victoria 3004 Australia
- Department of Clinical Haematology, Central Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria 3004 Australia
| |
Collapse
|
7
|
Rambaldi A, Dellacasa CM, Finazzi G, Carobbio A, Ferrari ML, Guglielmelli P, Gattoni E, Salmoiraghi S, Finazzi MC, Di Tollo S, D'Urzo C, Vannucchi AM, Barosi G, Barbui T. A pilot study of the Histone-Deacetylase inhibitor Givinostat in patients with JAK2V617F positive chronic myeloproliferative neoplasms. Br J Haematol 2010; 150:446-55. [PMID: 20560970 DOI: 10.1111/j.1365-2141.2010.08266.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A phase II A study was conducted to evaluate the safety and efficacy of Givinostat, a novel Histone-Deacetylases inhibitor, in patients with Polycythaemia Vera (PV, n = 12), Essential Thrombocythaemia (ET, n = 1) and Myelofibrosis (n = 16), bearing the JAK2V617F mutation. The study was approved by the local ethics committees and all human participants gave written informed consent. Givinostat was given orally for 24 weeks at a starting dose of 50 mg twice daily. The median treatment duration was 20 weeks. Reasons for treatment discontinuation were disease progression (n = 6), grade 2 thrombocytopenia (n = 1), psychiatric symptoms (n = 1) and withdrawn consent (n = 2). A dose reduction was applied in 10 patients while a temporary interruption occurred in 15. Among 13 PV/ET patients, 1 complete, 6 partial and 4 no responses were documented at study end while 2 patients went off-study, prematurely. Three major responses were registered among 16 MF patients. Pruritus disappeared in most patients and reduction of splenomegaly was observed in 75% of PV/ET and 38% of MF patients. Reverse transcription polymerase chain reaction identified a trend to reduction of the JAK2V617F allele burden. Givinostat was well tolerated and could induce haematological response in most PV and some MF patients.
Collapse
|
8
|
Rambaldi A. Therapy of myelofibrosis (excluding JAK2 inhibitors). Int J Hematol 2010; 91:180-8. [PMID: 20178012 DOI: 10.1007/s12185-010-0532-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2010] [Accepted: 02/07/2010] [Indexed: 10/19/2022]
Abstract
Myelofibrosis shows a progressive clinical course and usually a poor, lethal prognosis. Allogeneic transplantation is an effective, potentially curable treatment approach although only a minority of patients may currently benefit from it. New effective treatment strategies are becoming available for this disease, including not only JAK2 inhibitors, but also other innovative drugs, targeting more general oncogenic mechanisms and the epigenetic control of cell proliferation and differentiation.
Collapse
Affiliation(s)
- Alessandro Rambaldi
- Divisione di Ematologia, Ospedali Riuniti, Largo Barozzi 1, 24100 Bergamo, Italy.
| |
Collapse
|
9
|
Vannucchi AM, Guglielmelli P, Rambaldi A, Bogani C, Barbui T. Epigenetic therapy in myeloproliferative neoplasms: evidence and perspectives. J Cell Mol Med 2009; 13:1437-50. [PMID: 19522842 PMCID: PMC3828857 DOI: 10.1111/j.1582-4934.2009.00827.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2009] [Accepted: 06/03/2009] [Indexed: 12/18/2022] Open
Abstract
The classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs), which include polycythaemia vera, essential thrombocythaemia and primary myelofibrosis, originate from a stem cell-derived clonal myeloproliferation that manifests itself with variable haematopoietic cell lineage involvement; they are characterized by a high degree of similarities and the chance to transform each to the other and to evolve into acute leukaemia. Their molecular pathogenesis has been associated with recurrent acquired mutations in janus kinase 2 (JAK2) and myeloproliferative leukemia virus oncogene (MPL). These discoveries have simplified the diagnostic approach and provided a number of clues to understanding the phenotypic expression of MPNs; furthermore, they represented a framework for developing and/or testing in clinical trials small molecules acting as tyrosine kinase inhibitors. On the other hand, evidence of abnormal epigenetic gene regulation as a mechanism potentially contributing to the pathogenesis and the phenotypic diversity of MPNs is still scanty; however, study of epigenetics in MPNs represents an active field of research. The first clinical trials with epigenetic drugs have been completed recently, whereas others are still ongoing; results have been variable and at present do not allow any firm conclusion. Novel basic and translational information concerning epigenetic gene regulation in MPNs and the perspectives for therapy will be critically addressed in this review.
Collapse
Affiliation(s)
- Alessandro M Vannucchi
- UF di Ematologia, Dip. Area Critica Medico-Chirugica, Università di Firenze, Firenze, Italy.
| | | | | | | | | |
Collapse
|