HCK and BTK are key targets of KIN-8194 activity in MYD88-mutated WM cells. (A) Dose-response curves for vector only, HCK^WT, or HCK^T333M transduced BCWM.1 and MWCL-1 WM cells after treatment with KIN-8194 for 72 hours. (B) Relative pHCK^Tyr410 levels by Phosflow analysis treatment of KIN-8194 at indicated concentrations for 1.0 hours in vector only, HCK^WT, or HCK^T333M transduced MYD88-mutated BCWM.1 and MWCL-1 WM cells. (C) pBTK^Y223, pSYK^Y525/526, pAKT^S473, pERK1/2^T202/Y204 expression by western blot analysis in HCK^WT or HCK^T333M transduced BCWM.1 and MWCL-1 WM cells after treatment with KIN-8194 at indicated concentrations for 1.0 hours. The expression levels of total BTK, SYK, AKT, and ERK1/2 in these cells and protein loading control GAPDH are also shown. Experiments were performed at least twice, with representative blots shown. Ab, antibody.