Inhibition of CREB Binding and Function with a Dual-Targeting Ligand.

Area of Science:

• Molecular Biology
• Cancer Research
• Drug Discovery

Background:

• CBP/p300 acts as a transcriptional coactivator, regulating gene expression through interactions with activators.
• Dysregulation of protein-protein interactions (PPIs) involving the CBP/p300 KIX domain is linked to various cancers.
• The KIX domain is challenging to drug due to its shallow binding surfaces.

Purpose of the Study:

• To develop a novel, potent inhibitor of the KIX-CREB PPI.
• To evaluate the anti-cancer potential of new KIX-targeting peptides.
• To expand the dual-targeting strategy for inhibiting transcriptional coactivators.

Main Methods:

• Design and synthesis of a second-generation branched peptide analogue, CREBLL-tide.
• Assessment of CREBLL-tide's potency and selectivity against KIX-CREB PPI.
• Evaluation of CREBLL-tide's antiproliferation activity in breast cancer cells.

Main Results:

• CREBLL-tide demonstrated higher potency and selectivity in inhibiting the KIX-CREB PPI compared to previous analogues.
• The most effective CREBLL-tide analogue exhibited significant and selective antiproliferation activity in breast cancer cells.
• The study validates CREBLL-tide as a tool for studying KIX-activator roles in cancer.

Conclusions:

• CREBLL-tide represents an advanced peptide inhibitor for the KIX-CREB interaction.
• This peptide shows therapeutic potential for breast cancer treatment.
• The findings support a dual-targeting strategy for inhibiting coactivator-mediated gene activation in cancer.