The Expression of SSR2 in Pan-Cancer and Its Impact on Patient Survival: A Comprehensive Bioinformatics Analysis

Background: Given that aberrant glycosylation acts as a catalyst for tumorigenesis, elucidating Signal Sequence Receptor 2 (SSR2)'s specific patterns is essential to unlock its potential as a prognostic biomarker and clarify its mechanistic role in cancer biology. This study aims to comprehensively characterize the expression landscape and functional significance of SSR2, a pivotal subunit of the oligosaccharyltransferase complex, across normal human tissues and diverse malignancies. Methods: In this investigation, we utilized advanced bioinformatics resources, including the Human Protein Atlas (HPA), Genotype-Tissue Expression (GTEx), The Cancer Genome Atlas (TCGA), and CPTAC databases, to analyze the expression levels of SSR2 across various human tissues and malignancies. The data were analyzed utilizing the Xiantao academic analysis tool. We performed comparative analyses of SSR2 expression in cancerous and adjacent normal tissues, assessed survival outcomes associated with SSR2 expression levels, and conducted mutation and methylation analyses using cBioPortal and other relevant platforms. Results: Our findings revealed that SSR2 was predominantly expressed in the pancreas, epididymis, and ovary. Notably, significant differences in SSR2 expression were observed between cancerous and adjacent normal tissues in bladder urothelial carcinoma, breast cancer, and colorectal cancer. High levels of SSR2 correlated with poorer overall survival in adrenocortical carcinoma, esophageal cancer, and clear cell renal carcinoma, while SSR2 expression exhibited a protective effect in ovarian serous cystadenocarcinoma. Furthermore, SSR2 mutations were frequently observed in uterine sarcoma and liver cancer. Methylation analysis identified cg24557248, a CpG site, as a promising prognostic biomarker in clear cell renal carcinoma; increased methylation at this site was linked to improved survival outcomes. Conclusions: This study emphasizes the complex role of SSR2 in cancer biology, showcasing its potential as both a biomarker and a therapeutic target. Furthermore, the link between SSR2 and tumor immune cell infiltration indicates its role in shaping tumor microenvironments. Future investigations should aim to clarify how SSR2 affects tumor growth and immune regulation, which could lead to innovative therapeutic approaches for cancer treatment.