Design of Hydrazide-Bearing HDACIs Based on Panobinostat and Their p53 and FLT3-ITD Dependency in Antileukemia Activity

J Med Chem. 2020 May 28;63(10):5501-5525. doi: 10.1021/acs.jmedchem.0c00442. Epub 2020 May 6.


Here, we present a new series of hydrazide-bearing class I selective HDAC inhibitors designed based on panobinostat. The cap, linker, and zinc-binding group were derivatized to improve HDAC affinity and antileukemia efficacy. Lead inhibitor 13a shows picomolar or low nanomolar IC50 values against HDAC1 and HDAC3 and exhibits differential toxicity profiles toward multiple cancer cells with different FLT3 and p53 statuses. 13a indirectly inhibits the FLT3 signaling pathway and down-regulates master antiapoptotic proteins, resulting in the activation of pro-caspase3 in wt-p53 FLT3-ITD MV4-11 cells. While in the wt-FLT3 and p53-null cells, 13a is incapable of causing apoptosis at a therapeutic concentration. The MDM2 antagonist and the proteasome inhibitor promote 13a-triggered apoptosis by preventing p53 degradation. Furthermore, we demonstrate that apoptosis rather than autophagy is the key contributing factor for 13a-triggered cell death. When compared to panobinostat, 13a is not mutagenic and displays superior in vivo bioavailability and a higher AUC0-inf value.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / metabolism*
  • Antineoplastic Agents / therapeutic use
  • Cell Line, Tumor
  • Drug Design
  • Histone Deacetylase Inhibitors / chemistry
  • Histone Deacetylase Inhibitors / metabolism*
  • Histone Deacetylase Inhibitors / therapeutic use
  • Leukemia, Myeloid, Acute / drug therapy
  • Leukemia, Myeloid, Acute / metabolism*
  • Male
  • Mice
  • Panobinostat / chemistry
  • Panobinostat / metabolism*
  • Panobinostat / therapeutic use
  • Tumor Suppressor Protein p53 / antagonists & inhibitors
  • Tumor Suppressor Protein p53 / metabolism*
  • fms-Like Tyrosine Kinase 3 / antagonists & inhibitors
  • fms-Like Tyrosine Kinase 3 / metabolism*


  • Antineoplastic Agents
  • Histone Deacetylase Inhibitors
  • Trp53 protein, mouse
  • Tumor Suppressor Protein p53
  • Panobinostat
  • Flt3 protein, mouse
  • fms-Like Tyrosine Kinase 3