CD274 and cancer: Other mechanisms underlying relationship of NEFM DNA methylation with immune infiltration and poor prognosis in BRCA may include cytokine–cytokine receptor interaction, viral protein interaction with cytokine and cytokine receptor, chemokine signaling pathway, natural killer cell-mediated cytotoxicity, primary immunodeficiency, T cell receptor signaling pathway, IL-17 signaling pathway and PD-L1 expression and PD-1 checkpoint pathway in cancer, which are significantly associated with NEFM DNA methylation by KEGG enrichment analysis.