Work

The Colorectal Cancer Glycocode: Tumour Sialylation Is Associated with an Immune-Excluded Phenotype and Distinct Therapeutic Signatures

Year: 2026

Type: article

Abstract: BACKGROUND: Tumour glycosylation regulates immune modulation and progression, but whether the CRC sialylome-the complete repertoire of sialylated glycans-defines a biologically distinct subtype remains unclear. We investigated how the "sugar code" shapes CRC biology, immunity, and therapeutic response. METHODS: Transcriptomic data from three CRC cohorts (TCGA, Sidra-LUMC, and CPTAC-2; n = 988) were batch-corrected and integrated. Single-sample gene set enrichment analysis (ssGSEA) quantified sialyltransferase expression, sialic acid metabolism, EMT, MDR mechanisms, immune phenotypes, and Siglec-associated transcriptional signatures. GSEA, gene ontology enrichment analysis (GOEA), and drug ontology enrichment analysis (DOEA) characterised pathways and identified drug response-associated transcriptional signatures. RESULTS: mutations. At the transcriptional level, Sialyl-High tumours were associated with a mesenchymal, stromal-remodelling programme accompanied by reduced proliferative activity. They demonstrated enrichment of vesicular trafficking-related pathways alongside reduced representation of canonical efflux-associated programmes. Critically, the sialylome was associated with Siglec-related immune signatures, with sialylated glycan-related gene expression correlating with Siglec receptor expression (CD33 and SIGLEC7/9/10), consistent with an immune-inflamed yet structurally excluded microenvironment. DOEA identified selective enrichment of drug-response signatures related to sialic acid metabolism inhibitors (oseltamivir and Neu5Ac) and glycocalyx-disrupting agents (ginsenosides and soyasaponins). CONCLUSIONS: The CRC sialylome is associated with tumour phenotypic variation, including immune-excluded states linked to Siglec-associated transcriptional signatures and patterns consistent with non-canonical drug resistance programmes. These findings position the "sugar code" as a central organising principle in CRC and identify glycan-directed therapies as a promising strategy for the targeting of this aggressive subtype.

Source: Biology

DOI: 10.3390/biology15090705

Authors: Abdulaziz Alfahed, Glowi Alasiri, Abdulrahman A. Alahmari

Institutions: Prince Sattam Bin Abdulaziz University, Imam Mohammad ibn Saud Islamic University

Language: English

Topic: Glycosylation and Glycoproteins Research

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,258