Targeting HIF-2α in Colorectal Cancer Reveals a Cholesterol Biosynthesis-Dependent Ferroptotic Vulnerability

Area of Science:

• Oncology
• Molecular Biology
• Metabolic Pathways

Background:

• Colorectal carcinoma (CRC) is a leading cause of cancer mortality, with increasing incidence in younger adults.
• Hypoxia-inducible factor 2 alpha (HIF-2α) is a validated driver of colorectal tumorigenesis.
• HIF-2α inhibitors are approved for other cancers but not yet explored in CRC.

Purpose of the Study:

• To investigate the efficacy of pharmacologic HIF-2α inhibition in colorectal cancer.
• To identify therapeutic vulnerabilities associated with HIF-2α blockade in CRC.
• To explore combination strategies for enhanced CRC treatment.

Main Methods:

• In vitro and in vivo colorectal cancer models.
• CRISPR metabolic screening to identify drug dependencies.
• Pharmacologic inhibition of HIF-2α and cholesterol biosynthesis (statins).
• Mechanistic studies including ferroptosis assays and genetic knockdown.

Main Results:

• HIF-2α inhibition alone did not suppress CRC growth.
• CRISPR screening revealed cholesterol biosynthesis as a critical dependency.
• Combination therapy with HIF-2α inhibitor (PT2385) and statins synergistically reduced CRC cell growth and induced cell death.
• Combined inhibition promoted ferroptosis, characterized by lipid peroxidation and reduced antioxidants.
• Ferroptosis inhibition reversed the anti-tumor effects.

Conclusions:

• HIF-2α blockade uncovers a metabolic vulnerability in cholesterol biosynthesis for CRC.
• Dual targeting of HIF-2α and cholesterol biosynthesis synergistically inhibits CRC growth.
• This combination strategy, utilizing FDA-approved statins, offers a clinically actionable approach to potentiate HIF-2α-targeted therapy for colorectal cancer.