OAS3 is a Co-Immune Biomarker Associated With Tumour Microenvironment, Disease Staging, Prognosis, and Treatment Response in Multiple Cancer Types

2′,5′-oligoadenylate synthase (OAS) is a class of enzymes induced by interferons and mainly encoded by the OAS1, OAS2, and OAS3 genes, which activate the potential RNA enzymes to degrade viral mRNA, inhibit viral protein synthesis and promote apoptosis in virus-infected cells.OAS3is associated with breast cancer prognosis. However, the expression and prognosis ofOAS3and tumour-infiltrating lymphocytes in pan-cancer remain unknown. In the present study, we have systematically investigated and confirmed the role ofOAS3in tumour immune infiltration, immune escape, tumour progression, response to treatment, and prognosis of different cancer types using various bioinformatics methods. The findings suggest thatOAS3is aberrantly expressed in almost all TCGA cancer types and subtypes and is associated with tumour staging, metastasis, and prognostic deterioration in different tumours. In addition,OAS3expression is associated with the prognosis and chemotherapeutic outcomes of various cancers. In terms of immune-infiltrating levels,OAS3expression is positively associated with the infiltration of immunosuppressive cells. These findings suggest thatOAS3is correlated with prognosis and immune-infiltrating levels.