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Computational studies of difference in binding modes of peptide and non-peptide inhibitors to MDM2/MDMX based on

Jianzhong Chen1,2, Dinglin Zhang1, Yuxin Zhang1

  • 1Laboratory of Molecular Modeling and Design, State Kay Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116011, China.

International Journal of Molecular Sciences
|March 13, 2012
PubMed

Insights

Targeting the p53-MDM2/MDMX interaction with peptide and non-peptide inhibitors shows promise for cancer therapy. Molecular dynamics simulations reveal van der Waals forces and hydrophobic interactions drive binding, with peptide inhibitors offering more contacts.

Area of Science:

  • Biochemistry
  • Computational Chemistry
  • Drug Design

Background:

  • The p53 tumor suppressor protein is crucial for cancer prevention.
  • Inhibiting the interaction between p53 and its negative regulators, MDM2 and MDMX, is a key anticancer strategy.
  • Activating wild-type p53 in tumors can trigger cancer cell death.

Purpose of the Study:

  • To investigate the binding mechanisms of peptide and non-peptide inhibitors targeting MDM2/MDMX.
  • To understand the role of molecular interactions in inhibitor binding.
  • To provide insights for developing novel anticancer drugs targeting the p53 pathway.

Main Methods:

  • Molecular dynamics (MD) simulations were employed to analyze inhibitor binding.
  • Molecular mechanics generalized Born surface area (MM-GBSA) was used to calculate binding free energies.
  • Analysis of inhibitor-residue interactions, including van der Waals forces and hydrophobic interactions, was performed.

Main Results:

  • The calculated binding free energies correlated with experimental data.
  • Van der Waals energy was identified as a primary driving force for both peptide and non-peptide inhibitors.
  • Peptide inhibitors formed more extensive interactions with MDM2/MDMX compared to non-peptide inhibitors.
  • Hydrophobic interactions, including pi-pi, CH-pi, and CH-CH interactions, governed inhibitor binding within the hydrophobic cleft.
  • Steric clashes involving residue Tyr99 in MDMX were observed, potentially hindering inhibitor binding.

Conclusions:

  • Molecular dynamics simulations provide valuable insights into MDM2/MDMX inhibitor binding mechanisms.
  • Van der Waals and hydrophobic interactions are critical for inhibitor efficacy.
  • The findings suggest that Tyr99 in MDMX may present a challenge for inhibitor design.
  • This study offers theoretical guidance for developing potent dual-specific or MDMX-selective inhibitors for cancer therapy.
Keywords:
alanine scanningbinding free energymolecular dynamics simulationp53-MDM2/MDMX interaction

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