To explore the possible immune-regulatory role of SUV39H2 in different cancer types, we analyzed the relationship between SUV39H2 expression, immune cell infiltration, and immune checkpoint molecule expression in HNSCC, LIHC (Liver Hepatocellular Carcinoma), BRCA (Breast Invasive Carcinoma), and PAAD (Pancreatic Adenocarcinoma) tumors based on data from the TCGA database. Here, SUV39H2 is linked to head and neck squamous cell carcinoma.