Regulation and functional relevance of MARCKS. (A) Immunoblot for MARCKS in CRISPR /Cas9 OSU KO and respective OSU ctrl cells. (B) Migration (in percentage input control) toward CXCL12 in OSU KO and OSU ctrl normalized to OSU ctrl. (C) Immunoblot for AKT phosphorylation (S473) in OSU KO and OSU ctrl after treatment with ibrutinib (1 hour) and/or CXCL12 (2 minutes) and (D) corresponding densitometric analysis. (E) Immunoblot for MARCKS expression upon CD40L or BCR stimulation in a patient with CLL (blot representative of 7 different patients) with (F) densitometric analysis of n = 7 patients. (G) Induction of MARCKS in M-CLL and UM-CLL by CD40L stimulation. Blots are representative of 5 patients, respectively. (H) Immunoblot for MARCKS phosphorylation (S167/170) in OSU-CLL cells upon treatment with BTK inhibitors (1 µM, 60 minutes) ibrutinib and acalabrutinib (Acalab.) and PI3K inhibitor idelalisib (1 µM, 60 minutes). Blot is representative of n = 3 blots. (I) Immunoblot showing MARCKS phosphorylation (S167/170) upon ibrutinib treatment and/or BCR stimulation in a sample of a patient with CLL (blot representative of 4 different patients). DMSO, dimethyl sulfoxide.