title: S100A8/A9 at low concentration promotes tumor cell growth via RAGE ligation and MAP kinase-dependent pathway.
abstract: The complex formed by two members of the S100 calcium-binding protein family, S100A8/A9, exerts apoptosis-inducing activity against various cells, especially tumor cells. Here, we present evidence that S100A8/A9 also has cell growth-promoting activity at low concentrations. Receptor of advanced glycation end product (RAGE) gene silencing and cotreatment with a RAGE-specific blocking antibody revealed that this activity was mediated via RAGE ligation. To investigate the signaling pathways, MAPK phosphorylation and NF-kappaB activation were characterized in S100A8/A9-treated cells. S100A8/A9 caused a significant increase in p38 MAPK and p44/42 kinase phosphorylation, and the status of stress-activated protein kinase/JNK phosphorylation remained unchanged. Treatment of cells with S100A8/A9 also enhanced NF-kappaB activation. RAGE small interfering RNA pretreatment abrogated the S100A8/A9-induced NF-kappaB activation. Our data indicate that S100A8/A9-promoted cell growth occurs through RAGE signaling and activation of NF-kappaB.
authors.affiliation: Manitoba Institute of Cell Biology and Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Saeid
authors.initials: S
authors.lastname: Ghavami
authors.forename: Iran
authors.initials: I
authors.lastname: Rashedi
authors.forename: Brian M
authors.initials: BM
authors.lastname: Dattilo
authors.forename: Mehdi
authors.initials: M
authors.lastname: Eshraghi
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Chazin
authors.forename: Mohammad
authors.initials: M
authors.lastname: Hashemi
authors.forename: Sebastian
authors.initials: S
authors.lastname: Wesselborg
authors.forename: Claus
authors.initials: C
authors.lastname: Kerkhoff
authors.forename: Marek
authors.initials: M
authors.lastname: Los
mesh_terms: D040501:Calgranulin A / Q000502:physiology*; D040502:Calgranulin B / Q000502:physiology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000502:physiology; D005260:Female; D024243:HMGB1 Protein / Q000378:metabolism; D006801:Humans; D020935:MAP Kinase Signaling System / Q000502:physiology*; D016328:NF-kappa B / Q000502:physiology; D010766:Phosphorylation; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000502:physiology*
chemical_list: D040501:Calgranulin A; D040502:Calgranulin B; D024243:HMGB1 Protein; D016328:NF-kappa B; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D048049:Extracellular Signal-Regulated MAP Kinases