Inhibitors to STAT3, NF-κB, and AP-1 reduce HCK transcription in MYD88-mutated WM and ABC-DLBCL cells. (A) HCK promoter activities indicated by RLU% were determined by HCK promoter-driven luciferase reporter assay following treatment by inhibitors to STAT3 (STA-21), NF-kB (QNZ), and AP-1 (SR 11302) at one-fifth to one-twenty-fifth of their 50% effective concentration (EC₅₀) levels for 6 hours in BCWM.1 WM and TMD-8 ABC-DLBCL cells. (B) HCK mRNA levels were determined by TaqMan Gene Expression Assay following treatment by inhibitors to STAT3 (Galiellalactone), NF-kB (ACHP), and AP-1 (SP100030) at one-fourth to one-twentieth of their EC₅₀ levels for 24 hours in BCWM.1 WM and TMD-8 ABC-DLBCL cells. (C) HCK mRNA levels were determined by TaqMan Gene Expression Assay following treatment by the combination of STAT3 (Galiellalactone), NF-kB (Triptolide [PG490]), and AP-1 (SR 11302) inhibitors at less than one-tenth to one-fortieth of their EC₅₀ levels for 24 hours in BCWM.1 WM and TMD-8 ABC-DLBCL cells. Inhibitors used for each TF are labeled, and Comb indicates the combination of inhibitors to all 3 TFs. *P < .05; **P < .01; ***P < .001. DMSO, dimethyl sulfoxide.