Factor VIIa induces tissue factor-dependent up-regulation of interleukin-8 in a human keratinocyte line.
Tissue factor (TF), a transmembrane receptor for the serine protease coagulation factor VII(a) (FVIIa), is the main initiator of the coagulation cascade. Through incompletely elucidated mechanisms, TF serves additional functions in tumor-associated angiogenesis and metastasis. We have studied interleukin-8 (IL-8) as a possible link between TF-FVIIa complex formation and subsequent processes. Recombinant human FVIIa induced the up-regulation of both IL-8 mRNA and protein in a FVIIa dose- and time-dependent fashion. A neutralizing antibody to TF reduced this induction by 93 +/- 5%. Active site-inhibited FVIIa had no stimulatory effect and completely blocked that of FVIIa. This confirms that the increased IL-8 production was dependent on the formation of TF-FVIIa complexes and the proteolytic activity of FVIIa. The IL-8 promoter contains DNA binding sites for nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1). In response to FVIIa, the DNA binding activity of both NF-kappaB and AP-1 was enhanced in an electrophoretic mobility shift assay. In addition, the IL-8 promoter was transcriptionally activated both in a luciferase reporter system and a nuclear run-off assay. Moreover, IL-8 mRNA stability was significantly enhanced by FVIIa-induced activation of the mitogen-activated protein kinases ERK1/2 and p38. Taken together, TF-FVIIa signaling induced increased transcription as well as mRNA stabilization leading to the significant up-regulation of IL-8 protein synthesis.
Wang
Xiaolin
X
Biotechnology Centre of Oslo, University of Oslo, Gaustadalleen 21, 0349 Oslo, Norway.
Gjernes
Elisabet
E
Prydz
Hans
H
D002460:Cell Line; D004247:DNA / Q000378:metabolism; D015942:Factor VIIa / Q000494:pharmacology*; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics; D015603:Keratinocytes / Q000378:metabolism*; D019950:Mitogen-Activated Protein Kinase 1 / Q000502:physiology; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology; D016328:NF-kappa B / Q000378:metabolism; D011401:Promoter Regions, Genetic; D013925:Thromboplastin / Q000502:physiology*; D018808:Transcription Factor AP-1 / Q000378:metabolism; D015533:Transcriptional Activation; D015854:Up-Regulation; D048051:p38 Mitogen-Activated Protein Kinases
D016209:Interleukin-8; D016328:NF-kappa B; D018808:Transcription Factor AP-1; D004247:DNA; D013925:Thromboplastin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D015942:Factor VIIa