title: Inhibition of protein kinase CK2 suppresses tumor necrosis factor (TNF)-α-induced leukocyte-endothelial cell interaction.
abstract: Inflammatory endothelial processes are regulated by the nuclear factor-κB (NF-κB) pathway, which involves phosphorylation of p65. Because p65 is a substrate of CK2, we herein investigated, whether this pleiotropic protein kinase may be a beneficial anti-inflammatory target. For this purpose, we analyzed in human dermal microvascular endothelial cells (HDMEC) the effect of CK2 inhibition by quinalizarin and CX-4945 on cell viability, adhesion molecule expression and NF-κB pathway activation. Leukocyte binding to HDMEC was assessed in an in vitro adhesion assay. Dorsal skinfold chambers in BALB/c mice were used to study leukocyte-endothelial cell interaction and leukocyte transmigration by means of repetitive intravital fluorescence microscopy and immunohistochemistry. We found that quinalizarin and CX-4945 effectively suppressed the activity of CK2 in HDMEC without affecting their viability. This was associated with a significant down-regulation of tumor necrosis factor (TNF)-α-induced E-selectin, intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 expression due to a reduction of shuttling, phosphorylation and transcriptional activity of the NF-κB complex. In consequence, leukocyte binding to quinalizarin- and CX-4945-treated HDMEC was diminished. Finally, CX-4945 treatment significantly decreased the numbers of adherent and transmigrated leukocytes in dorsal skinfold chambers exposed to TNF-α in vivo. These findings indicate that CK2 is a key regulator of leukocyte-endothelial cell interaction in inflammation by regulating the expression of E-selectin, ICAM-1 and VCAM-1 via affecting the transcriptional activity of the NF-κB complex. Accordingly, CK2 represents a promising target for the development of novel anti-inflammatory drugs.
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, 66421 Homburg/Saar, Germany. Electronic address: emmanuel.ampofo@uks.eu.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Ampofo
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Jeannette
authors.initials: J
authors.lastname: Rudzitis-Auth
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Indra N
authors.initials: IN
authors.lastname: Dahmke
authors.affiliation: Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Oliver G
authors.initials: OG
authors.lastname: Rössler
authors.affiliation: Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Gerald
authors.initials: G
authors.lastname: Thiel
authors.affiliation: Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Mathias
authors.initials: M
authors.lastname: Montenarh
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Menger
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: Matthias W
authors.initials: MW
authors.lastname: Laschke
keywords: Dorsal skinfold chamber; ICAM-1; Intravital fluorescence microscopy; Leukocyte adhesion; NF-κB; VCAM-1