Discovery of novel BRD4-BD2 inhibitors via in silico approaches: QSAR techniques, molecular docking, and molecular...

Area of Science:

• Medicinal Chemistry
• Computational Drug Design
• Molecular Pharmacology

Background:

• Bromodomain-containing protein 4 (BRD4) is implicated in various cancers, with current inhibitors having limitations.
• Targeting the BRD4-BD2 domain is a promising strategy, as BD1 inhibition affects cell differentiation.
• There is a need for novel BRD4-BD2 inhibitors with improved efficacy and specificity.

Purpose of the Study:

• To develop and validate Quantitative Structure-Activity Relationship (QSAR) models for BRD4-BD2 inhibitors.
• To design novel, high-activity BRD4-BD2 inhibitors based on QSAR and computational modeling.
• To investigate the binding mechanisms and stability of designed inhibitors using molecular docking and simulations.

Main Methods:

• Construction of QSAR models (HQSAR, CoMFA, CoMSIA, Topomer CoMFA) using 49 known compounds.
• Design of new compounds guided by QSAR results and R-group searching.
• Molecular docking, molecular dynamics (MD) simulations, and free energy calculations to assess binding affinity and stability.

Main Results:

• QSAR models demonstrated good reliability (q² > 0.6) and predictive ability (r²pred > 0.6) for BRD4-BD2 inhibition.
• Twenty new compounds were designed with predicted high activity, favorable docking scores, and suitable ADMET properties.
• Molecular simulations confirmed stable binding interactions with key residues (Asn351, Cys347, Tyr350, Pro293, Asp299) in the BRD4-BD2 active site.

Conclusions:

• The developed QSAR models provide a reliable theoretical basis for designing BRD4-BD2 inhibitors.
• The newly designed compounds exhibit promising potential as novel BRD4-BD2 inhibitors.
• This study offers valuable insights and a theoretical foundation for the development of next-generation BRD4-BD2 targeted cancer therapeutics.