TY - JOUR
T1 - Dual PI3K/AKT/mTOR Inhibitor BEZ235 synergistically enhances the activity of JAK2 inhibitor against cultured and primary human myeloproliferative neoplasm cells
AU - Fiskus, Warren
AU - Verstovsek, Srdan
AU - Manshouri, Taghi
AU - Smith, Jacqueline E.
AU - Peth, Karissa
AU - Abhyankar, Sunil
AU - McGuirk, Joseph
AU - Bhalla, Kapil N.
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 2013/5
Y1 - 2013/5
N2 - Hemopoietic progenitor cells (HPC) from myeloproliferative neoplasms (MPN) such as myelofibrosis commonly express mutant JAK2-V617F or other mutations that are associated with increased activities of JAK-STAT5/3, RAS/RAF/MAPK, and PI3K/AKT/mTOR pathways. This confers proliferative and survival advantage on the MPN HPCs. Treatment with JAK tyrosine kinase inhibitor (TKI), for example, TG101209, TG101348 (SAR302503), or INCB018424 (ruxolitinib), inhibits mutant JAK2-mediated signaling. Although effective in reducing constitutional symptoms and splenomegaly, treatment with JAK-TKI does not ameliorate myelofibrosis or significantly improve survival of patients with advanced myelofibrosis. Here, we show that treatment with the dual phosphoinositide-3-kinase (PI3K)/AKT and mTOR inhibitor BEZ235 attenuated PI3K/AKT and mTOR signaling, as well as induced cell-cycle growth arrest and apoptosis of the cultured human JAK2-V617F-expressing HEL92.1.7 (HEL), UKE1 cells, and primary CD34+ myelofibrosis (MF)-MPN cells. Treatment with BEZ235 also induced significant apoptosis of the JAK2-TKI resistant HEL/TGR cells that were selected for resistance against JAK-TKI. Cotreatment with BEZ235 and JAK2-TKI (TG101209 and SAR302503) synergistically induced lethal activity against the cultured and primary CD34+ MPN cells while relatively sparing the normal CD34+ HPCs. These findings create a compelling rationale to determine the in vivo activity of dual PI3K/mTOR inhibitors in combination with JAK inhibitors against myelofibrosis HPCs.
AB - Hemopoietic progenitor cells (HPC) from myeloproliferative neoplasms (MPN) such as myelofibrosis commonly express mutant JAK2-V617F or other mutations that are associated with increased activities of JAK-STAT5/3, RAS/RAF/MAPK, and PI3K/AKT/mTOR pathways. This confers proliferative and survival advantage on the MPN HPCs. Treatment with JAK tyrosine kinase inhibitor (TKI), for example, TG101209, TG101348 (SAR302503), or INCB018424 (ruxolitinib), inhibits mutant JAK2-mediated signaling. Although effective in reducing constitutional symptoms and splenomegaly, treatment with JAK-TKI does not ameliorate myelofibrosis or significantly improve survival of patients with advanced myelofibrosis. Here, we show that treatment with the dual phosphoinositide-3-kinase (PI3K)/AKT and mTOR inhibitor BEZ235 attenuated PI3K/AKT and mTOR signaling, as well as induced cell-cycle growth arrest and apoptosis of the cultured human JAK2-V617F-expressing HEL92.1.7 (HEL), UKE1 cells, and primary CD34+ myelofibrosis (MF)-MPN cells. Treatment with BEZ235 also induced significant apoptosis of the JAK2-TKI resistant HEL/TGR cells that were selected for resistance against JAK-TKI. Cotreatment with BEZ235 and JAK2-TKI (TG101209 and SAR302503) synergistically induced lethal activity against the cultured and primary CD34+ MPN cells while relatively sparing the normal CD34+ HPCs. These findings create a compelling rationale to determine the in vivo activity of dual PI3K/mTOR inhibitors in combination with JAK inhibitors against myelofibrosis HPCs.
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U2 - 10.1158/1535-7163.MCT-12-0862
DO - 10.1158/1535-7163.MCT-12-0862
M3 - Article
C2 - 23445613
AN - SCOPUS:84877670562
SN - 1535-7163
VL - 12
SP - 577
EP - 588
JO - Molecular Cancer Therapeutics
JF - Molecular Cancer Therapeutics
IS - 5
ER -