MAN1A1 promotes colorectal cancer liver metastasis by maintaining TGFBR2 protein stability

Emerging biochemical and genetic evidence has firmly established aberrant protein glycosylation as a critical regulator of oncogenic transformation, with glycocalyx remodelling profoundly influencing tumor microenvironment dynamics and metastatic progression. Despite the well-documented association between metastatic dissemination and poor clinical outcomes in patients with colorectal cancer, the underlying molecular mechanisms remain incompletely characterized. Through integrative analysis of single-cell RNA sequencing data from a public database, we identify the Golgi-resident α-1,2-mannosidase MAN1A1 as a consistently upregulated enzyme in malignant epithelial cells derived from colorectal cancer liver metastases. Clinically, elevated MAN1A1 expression is correlated with reduced overall survival, suggesting that MAN1A1 is both a prognostic biomarker and therapeutic target for colorectal cancer liver metastases. Genetic manipulation of MAN1A1 in colorectal cancer cells demonstrates that although the proliferation capacity of colorectal cancer cells remains unchanged, MAN1A1 overexpression significantly enhances migratory and invasive capacities in transwell assays, suggesting its specific involvement in metastatic progression. Mechanistic investigations reveal that MAN1A1 exerts its pro-metastatic effects by significantly prolonging the TGFBR2 protein half-life. Together, our work identifies MAN1A1 as both a prognostic biomarker and a promising therapeutic target, highlighting the critical role of glycan remodelling in the metastatic progression of colorectal cancer.