Snail1 Induced Suppression of Proliferation via EGR1, FOXO1, and CEPBγ Creates a Vulnerability for Targeting...

Area of Science:

• Oncology
• Cancer Biology
• Molecular Biology

Background:

• Prostate cancer (PCa) metastasis remains a significant clinical challenge, with ~36,000 annual deaths.
• Epithelial-mesenchymal-transition (EMT) is implicated in PCa metastasis, yet its effect on proliferation is unclear due to limited models.
• Understanding EMT's role in PCa proliferation is crucial for developing effective treatments.

Purpose of the Study:

• To investigate the mechanisms by which Snail1, an EMT driver in PCa, influences cancer cell proliferation.
• To identify downstream targets of Snail1 that mediate its effects on cell cycle progression.
• To explore the implications of Snail1-driven cell cycle suppression for therapeutic targeting.

Main Methods:

• Transiently induced Snail1 (SNAI1) expression in three PCa cell lines (C4-2B, 22Rv1, DU145).
• Utilized RNA-sequencing (RNA-seq), ChIP-sequencing (ChIP-Seq), qRT-PCR, shRNA, and immunoblotting.
• Analyzed Snail1's impact on cell cycle progression, gene expression, and protein interactions.

Main Results:

• Snail1 suppressed proliferation and G2/M cell cycle progression without increasing cell death.
• Identified Snail1-mediated upregulation of CEBPγ, EGR1, FOXO1, p21, stress genes (SESN3, SOD3), and apoptotic factors (Puma, Bax, Noxa).
• ChIP-Seq revealed direct Snail1 binding to promoters of p21, cyclin B2/G1, EGR1, and CEBPγ, highlighting the EGR1/FOXO1 axis in regulating stress and apoptosis.

Conclusions:

• Discovered novel downstream targets of Snail1, enhancing understanding of EMT's role in PCa.
• Snail1-induced cell cycle suppression limits stress signaling, apoptosis, and senescence, creating a potential therapeutic vulnerability.
• Findings provide a foundation for developing targeted therapies against metastatic prostate cancer.