A Somatically Acquired Enhancer of the Androgen Receptor Is a Noncoding Driver in Advanced Prostate Cancer

Area of Science:

• Oncology
• Genetics
• Molecular Biology

Background:

• Androgen receptor (AR) activity is a key driver of therapeutic resistance in advanced prostate cancer.
• Gene amplification of the AR locus is a common mechanism for resistance.

Purpose of the Study:

• To identify and functionally characterize novel regulatory elements contributing to AR activity and therapeutic resistance.
• To explore the potential of targeting noncoding regulatory elements for prostate cancer therapy.

Main Methods:

• Genome editing was used to perturb a newly identified AR enhancer.
• Proliferation assays were conducted under varying androgen conditions and in the presence of enzalutamide.
• Epigenetic data from primary prostate tumors and benign specimens were analyzed.

Main Results:

• A somatically acquired AR enhancer, located centromeric to the AR gene, was identified.
• Perturbation of this enhancer decreased cancer cell proliferation by suppressing AR levels.
• Insertion of an additional copy of the enhancer increased proliferation and reduced sensitivity to enzalutamide, particularly under low androgen conditions.

Conclusions:

• The identified AR enhancer plays a critical role in driving prostate cancer progression and therapeutic resistance.
• Epigenomic profiling in primary tumors is essential for understanding resistance mechanisms.
• Genome editing is a valuable tool for characterizing noncoding elements and their functional impact.
• Targeting AR regulatory elements represents a promising therapeutic vulnerability in advanced prostate cancer.