title: Group I PAK inhibitor IPA-3 induces cell death and affects cell adhesivity to fibronectin in human hematopoietic cells.
abstract: P21-activated kinases (PAKs) are involved in the regulation of multiple processes including cell proliferation, adhesion and migration. However, the current knowledge about their function is mainly based on results obtained in adherent cell types. We investigated the effect of group I PAK inhibition using the compound IPA-3 in a variety of human leukemic cell lines (JURL-MK1, MOLM-7, K562, CML-T1, HL-60, Karpas-299, Jurkat, HEL) as well as in primary blood cells. IPA-3 induced cell death with EC50 ranging from 5 to more than 20 μM. Similar range was found for IPA-3-mediated dephosphorylation of a known PAK downstream effector, cofilin. The cell death was associated with caspase-3 activation, PARP cleavage and apoptotic DNA fragmentation. In parallel, 20 μM IPA-3 treatment induced rapid and marked decrease of the cell adhesivity to fibronectin. Per contra, partial reduction of PAK activity using lower dose IPA-3 or siRNA resulted in a slight increase in the cell adhesivity. The changes in the cell adhesivity were also studied using real-time microimpedance measurement and by interference reflection microscopy. Significant differences in the intracellular IPA-3 level among various cell lines were observed indicating that an active mechanism is involved in IPA-3 transport.
authors.affiliation: Department of Cellular Biochemistry, Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Kateřina
authors.initials: K
authors.lastname: Kuželová
authors.affiliation: Department of Cellular Biochemistry, Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Dana
authors.initials: D
authors.lastname: Grebeňová
authors.affiliation: Department of Cellular Biochemistry, Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Aleš
authors.initials: A
authors.lastname: Holoubek
authors.affiliation: Department of Cellular Biochemistry, Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Pavla
authors.initials: P
authors.lastname: Röselová
authors.affiliation: Department of Cellular Biochemistry, Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Adam
authors.initials: A
authors.lastname: Obr
mesh_terms: D051339:Actin Depolymerizing Factors / Q000737:chemistry / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D001773:Blood Cells / Q000166:cytology* / Q000187:drug effects*; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004220:Disulfides / Q000378:metabolism / Q000494:pharmacology*; D005353:Fibronectins / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D020868:Gene Silencing; D006410:Hematopoiesis / Q000187:drug effects; D006801:Humans; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D007938:Leukemia / Q000473:pathology; D008223:Lymphoma / Q000473:pathology; D009284:Naphthols / Q000378:metabolism / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000378:metabolism / Q000494:pharmacology*; D034741:RNA, Small Interfering / Q000235:genetics; D012694:Serine / Q000378:metabolism; D054462:p21-Activated Kinases / Q000037:antagonists & inhibitors* / Q000172:deficiency / Q000235:genetics
chemical_list: D051339:Actin Depolymerizing Factors; D004220:Disulfides; D005353:Fibronectins; C541795:IPA-3 compound; D009284:Naphthols; D047428:Protein Kinase Inhibitors; D034741:RNA, Small Interfering; D012694:Serine; D054462:p21-Activated Kinases