Abstract
Recent studies have identified a novel programmed cell death based on copper, named cuproptosis. However, as an anti-cuproptosis gene, the functional roles, definite mechanisms and prognostic value of CDKN2A in pan-cancer are largely unclear. The GEPIA2, cancer genome atlas (TCGA), the tumor immune estimation resource 2.0 and CPTAC databases were performed to validate the differential expression of CDKN2A in 33 tumors. The clinical features and survival prognosis analysis were conducted by GEPIA2 and UALCAN web tool. Genetic alteration analysis of CDKN2A in pan-cancer was also evaluated. Furthermore, the functional roles of CDKN2A were explored via DNA methylation analysis, tumor microenvironment, infiltration of immune cells, enrichment analysis and gene co-expression associated with cuproptosis and immune regulation. The CDKN2A expression, both at the transcriptional and translational level, was obviously upregulated in most cancer patients, which might lead to poor survival in certain cancer types. CDKN2A expression was significantly associated with tumor pathological stages in some cancer types. In adrenocortical carcinoma (ACC) and kidney renal clear cell carcinoma (KIRC), DNA methylation of CDKN2A was explored to induce poor clinical outcomes. Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis indicated that CDKN2A expression was closely related to several cancer-associated signaling pathways, such as the p53 signaling pathway, Cellular senescence, DNA replication and Cell cycle signaling pathways. Gene set enrichment analysis (GSEA) analysis suggested that aberrantly expressed CDKN2A took part in the cell cycle regulation, immune regulation and mitochondrial signaling pathways in certain cancer patients. In addition, aberrant CDKN2A expression was closely correlated to immune infiltration and the levels of immune-regulatory genes. The study deeply defined the concrete roles of cuproptosis-related gene CDKN2A in tumorigenesis. The results provided new insights and pieces of evidence for treatment.