• FOSB is downregulated in colon cancer tissues and acts as a tumor suppressor by inhibiting proliferation and promoting apoptosis.
• A novel FOSB-miR-133b-POU2F1 feedback loop is identified, where FOSB enhances miR-133b transcription, which represses POU2F1, and reduced POU2F1 relieves transcriptional repression of FOSB.
• The study provides mechanistic insights into the tumor-suppressive role of FOSB in colon cancer, offering potential therapeutic targets.
• The feedback loop may serve as a biomarker for prognosis and a target for therapeutic intervention in colon cancer.