Locking PDK1 in DFG-out conformation through 2-oxo-indole containing molecules: Another tools to fight glioblastoma

Eur J Med Chem. 2016 Aug 8:118:47-63. doi: 10.1016/j.ejmech.2016.04.003. Epub 2016 Apr 20.

Abstract

The phosphoinositide-dependent kinase-1 (PDK1) is one of the main components of the PI3K/Akt pathway. Also named the "master kinase" of the AGC family, PDK1 plays a critical role in tumorigenesis, by enhancing cell proliferation and inhibiting apoptosis, as well as in cell invasion and metastasis formation. Although there have been done huge efforts in discovering specific compounds targeting PDK1, nowadays no PDK1 inhibitor has yet entered the clinic. With the aim to pick out novel and potent PDK1 inhibitors, herein we report the design and synthesis of a new class of molecules obtained by merging the 2-oxo-indole nucleus with the 2-oxo-pyridonyl fragment, two moieties with high affinity for the PDK1 hinge region and its DFG-out binding site, respectively. To this purpose, a small series of compounds were synthesised and a tandem application of docking and Molecular Dynamic (MD) was employed to get insight into their mode of binding. The OXID-pyridonyl hybrid 8, possessing the lower IC50 (IC50 = 112 nM), was also tested against recombinant kinases involved in the PI3K/PDK1/Akt pathway and was subjected to vitro studies to evaluate the cytotoxicity and the inhibition of tumour cell migration. All together the results let us to consider 8, as a lead compound of a new generation of PDK1 inhibitors and encourage us to further studies in this direction.

Keywords: GBM stem cells; Glioblastoma; Kinase inhibitors; Oxindole derivatives; PDK1 inhibitors; Pyridonyl derivatives.

MeSH terms

  • 3-Phosphoinositide-Dependent Protein Kinases / antagonists & inhibitors*
  • 3-Phosphoinositide-Dependent Protein Kinases / chemistry*
  • 3-Phosphoinositide-Dependent Protein Kinases / metabolism
  • Amino Acid Motifs
  • Antineoplastic Agents / chemical synthesis
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / metabolism
  • Antineoplastic Agents / pharmacology
  • Apoptosis / drug effects
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Drug Design
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / metabolism
  • Enzyme Inhibitors / pharmacology
  • Glioblastoma / pathology*
  • Humans
  • Indoles / chemical synthesis
  • Indoles / chemistry*
  • Indoles / metabolism
  • Indoles / pharmacology*
  • Molecular Docking Simulation
  • Molecular Dynamics Simulation
  • Protein Domains
  • Signal Transduction / drug effects

Substances

  • Antineoplastic Agents
  • Enzyme Inhibitors
  • Indoles
  • 3-Phosphoinositide-Dependent Protein Kinases