KDM5 inhibition increases H3K4me3 levels in DLBCL cell lines. (A) The expression of the 4 KDM5 family members (KDM5A-D) was examined by quantitative reverse transcriptase-polymerase chain reaction in 10 DLBCL cell lines and normalized to the expression of GAPDH. Data are the mean ± standard error of the mean (SEM) of 3 independent experiments. (B) KDM5 family member expression was examined by RNA-seq in publicly available datasets of FL (ICGC, n = 97²¹ ) and DLBCL (TCGA, n = 48; ICGC, n = 74) patients, plus healthy GC B cells (BLUEPRINT²² ). RPKM, reads per kilobase million; TPM, transcripts per million. (C) SU-DHL-6 cells were treated with 1 µM KDM5-inh1 or 10 µM Compound-48 and KDM5-C70 for 48, 72, and 96 hours, followed by western blot analysis of H3K4me3 levels relative to H3. (D) The SU-DHL-6 and HT cell lines were treated with DMSO or increasing concentrations of KDM5-inh1 for 48 hours. Representative western blots for H3K4me3/me2/me1 (KDM5), H3K9me3/K36me3 (KDM4), H3K27me3 (KDM6), and H3 (i). Quantification of western blots relative to H3 (ii). Data are mean ± SEM of 3 independent experiments.