NOP2 and neoplasm: The relationships between NOP2 expression and the tumor immune microenvironment were assessed by estimating tumor-infiltrating immune cell proportions with Cell-type Identification By Estimating Relative Subsets Of RNA Transcripts (CIBERSORT), followed by correlation analyses with immune cell infiltration levels, immune checkpoint-related genes, tumor mutational burden (TMB), and microsatellite instability (MSI).