Selective Small-Molecule Activator of Patient-Derived GPX4 Variant.

Area of Science:

• Biochemistry
• Genetics
• Pharmacology

Background:

• Glutathione peroxidase 4 (GPX4) protects cells from ferroptosis by reducing lipid hydroperoxides.
• A homozygous R152H mutation in GPX4 causes Sedaghatian-type spondylometaphyseal dysplasia (SSMD) with loss of enzymatic activity.
• Targeting missense variants in crucial proteins is a significant challenge in developing therapeutics.

Purpose of the Study:

• To identify small molecules that selectively bind and restore the enzymatic activity of the GPX4 R152H variant.
• To evaluate the therapeutic potential of these molecules in patient-derived cells and disease models.

Main Methods:

• Screening of a 2.8 billion compound DNA-encoded chemical library for selective binding to GPX4 R152H.
• Structural optimization of identified lead compounds to improve potency.
• Assessing the restoration of GPX4 R152H enzymatic activity and cellular viability in patient-derived cells and ferroptosis models.

Main Results:

• Identified compounds with high selectivity for GPX4 R152H over wild-type GPX4.
• Optimized compounds demonstrated improved potency and restored GPX4 R152H enzymatic activity.
• Selected compounds specifically rescued the viability of SSMD patient-derived cells without affecting control cells or inducing ferroptosis.

Conclusions:

• A novel, high-throughput screening approach successfully identified targeted small-molecule therapeutics for a GPX4 missense variant.
• This strategy demonstrates potential for treating genetic disorders caused by point mutations in essential proteins.
• The findings offer a generalizable platform for developing precision medicines for a range of diseases, including cancers.