Reversing chemoresistance by small molecule inhibition of the translation initiation complex eIF4F

Area of Science:

• Oncology
• Molecular Biology
• Biochemistry

Background:

• Cap-dependent translation deregulation is linked to cancer development and progression.
• The eukaryotic initiation factor 4F (eIF4F) complex is crucial for the rate-limiting step of protein synthesis.
• Targeting eIF4F, which is at the intersection of the TOR signaling pathway, is a promising strategy for anticancer drug discovery.

Purpose of the Study:

• To identify inhibitors of eIF4F complex assembly using an ultra-high-throughput screen.
• To investigate the mechanism of action of identified inhibitors.
• To evaluate the therapeutic potential of eIF4F inhibition in reversing chemoresistance.

Main Methods:

• Ultra-high-throughput screening to identify eIF4F assembly inhibitors.
• Biochemical assays to confirm compound activity and mechanism.
• In vivo studies using a genetically engineered lymphoma mouse model.
• Molecular modeling for mechanistic insights.

Main Results:

• An identified compound was found to inhibit the interaction between eIF4F subunits, thereby blocking cap-dependent translation.
• This compound demonstrated the ability to reverse tumor chemoresistance in a lymphoma mouse model.
• The compound sensitized cancer cells to DNA damage-induced apoptosis.
• Molecular modeling provided insights into the inhibitor's mechanism of action.

Conclusions:

• Targeting the eIF4F complex is a validated strategy for cancer therapy.
• Inhibiting eIF4F assembly can modulate cancer cell chemosensitivity.
• This approach offers a potential method to overcome tumor chemoresistance and enhance treatment efficacy.