Novel BH4-BCL-2 Domain Antagonists Induce BCL-2-Mediated Apoptosis in Triple-Negative Breast Cancer

Area of Science:

• Oncology
• Molecular Biology
• Medicinal Chemistry

Background:

• Triple-negative breast cancer (TNBC) presents a significant clinical challenge due to a lack of targeted therapies and predictive biomarkers.
• Overexpression of the anti-apoptotic protein B-cell lymphoma 2 (BCL-2) is implicated in TNBC progression and chemoresistance.

Purpose of the Study:

• To design and evaluate novel small molecules targeting BCL-2 as a therapeutic strategy for TNBC.
• To assess the binding affinity, selectivity, and anti-cancer mechanisms of these novel compounds.

Main Methods:

• Design and synthesis of three novel BH4 mimetic small molecules (SM396, SM216, SM949) targeting BCL-2.
• In vitro mechanistic studies to validate target engagement, selectivity, and induction of apoptosis in cancer cells.
• In vivo efficacy assessment in a TNBC xenograft mouse model (MDA-MB-231).

Main Results:

• The novel compounds demonstrated high binding affinity (nanomolar range) and selectivity for BCL-2.
• Mechanistic studies confirmed selective targeting of cancer cells and induction of BCL-2-mediated apoptosis.
• Compounds exhibited significant anti-tumor activity as single agents in vivo at nanomolar doses.

Conclusions:

• SM216, SM396, and SM949 represent promising drug candidates for TNBC treatment.
• These BCL-2 targeting agents warrant further clinical investigation for their therapeutic potential in triple-negative breast cancer.