CACUL1 functions as a negative regulator of androgen receptor in prostate cancer cells

Area of Science:

• Oncology
• Molecular Biology
• Biochemistry

Background:

• The androgen receptor (AR) is crucial in prostate cancer (PCa) development and progression.
• Targeting AR signaling is a key strategy in PCa therapy.

Purpose of the Study:

• To investigate the role of CDK2-associated cullin 1 (CACUL1) in regulating AR activity.
• To explore CACUL1 as a potential therapeutic target in PCa.

Main Methods:

• Investigated the direct association between CACUL1 and AR.
• Assessed CACUL1's effect on AR transcriptional activity and LSD1-mediated transactivation.
• Analyzed LSD1 occupancy and H3K9me2 levels upon CACUL1 depletion.
• Examined the impact of CACUL1 and LSD1 on CDX-induced cell death in PCa cell lines.

Main Results:

• CACUL1 directly binds to AR and suppresses its transcriptional activity.
• CACUL1 competes with LSD1 for AR binding, repressing LSD1-mediated AR transactivation.
• CACUL1 depletion increases LSD1 occupancy at AR target promoters and decreases H3K9me2.
• CACUL1 and LSD1 exhibit opposing effects on CDX-induced cell death in AR-positive and metastatic PCa cells.

Conclusions:

• CACUL1 inhibits LSD1-mediated activation of the androgen receptor.
• CACUL1 functions as a suppressor of AR activity in prostate cancer.
• CACUL1 represents a potential novel antitumor target for prostate cancer treatment.