The histone methyltransferase SETMAR is a fusion protein that contains an N‐terminal histone lysine N‐methyltransferase domain and a C‐terminal transposase domain.[14] It has been reported that SETMAR is involved in the catalytic methylation of histone H3K4me2, H3K36me2, and H3K27me3 sites, thus participating in regulating gene expression.[15] Several studies have reported that SETMAR performs different functions in tumors, depending on genetic background[16, 17, 18]; thus, SETMAR is very important in both cancer development and treatment. This evidence concerns the gene SETMAR and cancer.