Pan-cancer analysis reveals SGO1 as a potential cancer prognostic and immunological biomarker.

Shugoshin 1 (SGO1) is primarily known for its critical functions in chromosome segregation during cell division, protecting cohesin complexes and ensuring accurate mitotic processes. Previous studies have reported SGO1's regulatory roles in isolated cancer types, but its pan-cancer significance and underlying mechanisms remain undefined. This study systematically investigates SGO1 in 33 cancer types, integrating multi-omics analyses and functional validation to reveal its role as a pan-cancer biomarker and therapeutic target. Using TCGA, GEPIA2, and HPA databases, we found SGO1 was significantly overexpressed in 19 cancer types compared to normal tissues. High SGO1 expression correlated with poorer overall survival (OS) and disease-free survival (DFS) in more than 10 cancers, validated by Kaplan-Meier analysis. Genomic analysis revealed frequent SGO1 mutations and DNA methylation dysregulation, while immune profiling showed associations with immune cell infiltration (B cells, CD8+ T cells) and PD-1/PD-L1 checkpoint genes. Protein-protein interaction and enrichment analyses uncovered BUB1 as a key co-expressed gene, suggesting a role in spindle checkpoint regulation. Functional assays in breast cancer cell line MDA-MB-231 and lung cancer cell line A549 showed SGO1 knockdown inhibited proliferation, migration, and invasion, with xenograft models confirming reduced tumor growth. Our findings establish SGO1 as a novel pan-cancer biomarker, linking its expression to tumor progression, immune evasion, and genomic instability. This study bridges bioinformatics with functional validation, offering new mechanistic insights and therapeutic avenues for SGO1-driven cancers.