Candida albicans drives colorectal cancer progression by inducing hypoxia signaling

Colorectal cancer (CRC) is the third leading cause of cancer-related mortality worldwide. Gut microbiota, including fungal species, are increasingly implicated in CRC progression, while the molecular mechanisms underlying host-fungal interactions in this context remain poorly understood. Here, we show that Candida albicans (C. albicans) activates pro-metastatic signaling pathways, MAPK and NF-κB, leading to upregulation of oncogenic transcription factors c-Jun and c-Myc. This cascade stabilizes and activates hypoxia-inducible factor 1α (HIF-1α), a central regulator of tumor metabolic reprogramming and angiogenesis, ultimately fostering a pro-tumorigenic microenvironment. Mechanistically, we identify candidalysin, a secreted peptide toxin of C. albicans, as a critical effector that engages epidermal growth factor receptor (EGFR) and toll-like receptor 2 (TLR2) in a species- and cancer cell type-dependent manner. These findings are further supported by patient-derived colonic organoids. Collectively, our study delineates a C. albicans-EGFR/TLR2-ERK/NF-κB-HIF-1α axis that promotes hypoxia-like responses in CRC, revealing a previously underappreciated role of fungal pathogens in shaping the tumor microenvironment and offering potential targets for therapeutic interventions. To identify the role of C. albicans in colorectal cancer progression, we cultured the colorectal cancer cell line without and with C. albicans under normoxia and hypoxia environment respectively, and performed RNA sequencing to analyze the transcriptome alteration.