Abstract

Colorectal cancer (CRC) remains a leading cause of cancer mortality globally, underscoring the need to identify key molecular drivers. Cell division cycle 20 (CDC20), a regulator of cell cycle progression, is frequently dysregulated in malignancies. Its specific role and mechanisms in CRC pathogenesis are poorly understood, warranting investigation to uncover novel therapeutic targets. In this study, CDC20 mRNA expression was quantified by quantitative real-time polymerase chain reaction (qRT-PCR), while its protein levels were assessed using Western blotting. Cell proliferation was evaluated via the 5-Ethynyl-2’-deoxyuridine (EdU) assay. Cell apoptosis was analyzed by flow cytometry. Migration and invasion capabilities were examined using wound-healing and Transwell invasion assays, respectively. Angiogenesis was assessed using a tube formation assay. To investigate the in vivo effects of CDC20 knockdown, a xenograft mouse model was employed to monitor tumor growth. Flow cytometry was performed to quantify CD206( +) macrophages. Mechanistic studies included chromatin immunoprecipitation (ChIP), dual-luciferase reporter, RNA immunoprecipitation (RIP), and methylated RNA immunoprecipitation (MeRIP) assays to explore GATA binding protein 6 (GATA6) and methyltransferase-like 3 (METTL3) interactions with CDC20. The results showed that CDC20 expression at the mRNA and protein levels was significantly upregulated in CRC tissues in comparison with normal colorectal tissues. Moreover, its protein expression was higher in CRC cells than in human normal colonic epithelial cells. Its knockdown suppressed CRC cell proliferation, migration, invasion, and tube formation, while promoting apoptosis. In addition, CDC20 depletion inhibited tumor growth and immune escape. Transcription factor GATA6 directly activated transcription of the CDC20 gene. Crucially, restoring CDC20 expression counteracted the tumor-suppressive effects of GATA6 knockdown on malignant behaviors and immune es