ST6GAL1-Mediated Sialylation Stabilizes PD-L1 and Drives Immunosuppressive Tumor Microenvironment in Colorectal Cancer.

ABSTRACT: Abnormal glycogene expression is a recognized cancer hallmark, but its impact on the colorectal cancer (CRC) tumor microenvironment (TME) remains unclear. Utilizing bioinformatics analysis on TCGA and GEO datasets, a seven-glycogene signature is identified for precise glycogene-based classification in CRC. ST6GAL1, a key focus, emerges as a significant predictor of poor prognosis, with its upregulation linked to unfavorable outcomes in CRC. Functional experiments demonstrate that loss of ST6GAL1 inhibits CRC proliferation, migration, invasion, and metastasis. ST6GAL1-mediated sialylation of PD-L1 is critical for maintaining its stability in colorectal cancer cells, and ST6GAL1 knockdown leads to reduced protein stability and increased ubiquitination. ST6GAL1 knockdown in MC38 tumor-bearing

SUBMITTER: Xu X 

PROVIDER: S-EPMC12622430 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature