To assess DNMT3A, SETD8 and DOT1L protein expression we selected four DLBCL cell lines with different DNMT3A, SETD8 and DOT1L gene expression: DB (high DNMT3A and SETD8 expression, low DOT1L expression), NUDUL1 (high DNMT3A and SETD8 expression), RI1 (high DNMT3A and DOT1L expression, low SETD8 expression) and SUDHL5 (low DNMT3A expression). This evidence concerns the gene DOT1L and diffuse large B-cell lymphoma.