Identification of PRIM2 as a new prognostic and immune-related marker in cancer based on a comprehensive pan-cancer analysis

Abstract

DNA Primase Subunit 2 (PRIM2) encodes a large subunit (p58C) of DNA primase, which plays an important role in DNA replication. However, the role of PRIM2 in cancer and immune regulation has not been elucidated. Therefore, in the present study, the expression profile of PRIM2 in cancer was investigated using publicly available databases like the Cancer Genome Atlas (TCGA), the Genotype-Tissue Expression (GTEx), the Broad Institute Cancer Cell Line Encyclopedia (CCLE) from the University of California Santa Cruz (UCSC) Xena website. PRIM2 expression was analyzed in paired normal to the adjacent tumor and unpaired cancer and normal tissues. The prognosis of PRIM2 in various cancers was studied using Cox regression and Kaplan-Meier analysis. The relationship between PRIM2 and tumor staging, tumor mutation burden (TMB), and microsatellite instability (MSI) was analyzed. Algorithms like cell type identification by estimating relative subsets of RNA transcripts (CIBERSORT), xCell, ssGSEA, and MCP-counter were used to study the correlation between PRIMA2 and tumor immune microenvironment, immune infiltrating cells, and immune-related genes (antigen processing and presentation genes, chemokines, chemokine receptors, HLA-related genes, immune checkpoints). Further, the correlation between PRIM2 and methyltransferase (DNMT1, DNMT3A, DNMT3B) from different databases. The biological processes and signaling pathways associated with PRIM2 in various tumors were studied. Finally, the correlation between the PRIM2 and the sensitivity of multiple drugs was analyzed using the National Cancer Institute (NCI)-60 database. The results show that PRIM2 was up-regulated in most tumors, high PRIM2 expression was associated with the different stages of cancer, and poor prognosis was observed. The results indicate that PRIM2 could potentially be used as a prognostic and immunotherapy target in tumors.