title: Targeting V-ATPase in primary human monocytes by archazolid potently represses the classical secretion of cytokines due to accumulation at the endoplasmic reticulum.
abstract: The macrolide archazolid inhibits vacuolar-type H(+)-ATPase (V-ATPase), a proton-translocating enzyme involved in protein transport and pH regulation of cell organelles, and potently suppresses cancer cell growth at low nanomolar concentrations. In view of the growing link between inflammation and cancer, we investigated whether inhibition of V-ATPase by archazolid may affect primary human monocytes that can promote cancer by sustaining inflammation through the release of tumor-promoting cytokines. Human primary monocytes express V-ATPase, and archazolid (10-100nM) increases the vesicular pH in these cells. Archazolid (10nM) markedly reduced the release of pro-inflammatory (TNF-α, interleukin-6 and -8) but also of anti-inflammatory (interleukin-10) cytokines in monocytes stimulated with LPS, without affecting cell viability up to 1000nM. Of interest, secretion of interleukin-1β was increased by archazolid. Comparable effects were obtained by the V-ATPase inhibitors bafilomycin and apicularen. The phosphorylation of p38 MAPK and ERK-1/2, Akt, SAPK/JNK or of the inhibitor of NFκB (IκBα) as well as mRNA expression of IL-8 were not altered by archazolid in LPS-stimulated monocytes. Instead, archazolid caused endoplasmic reticulum (ER) stress response visualized by increased BiP expression and accumulation of IL-8 (and TNF-α) at the ER, indicating a perturbation of protein secretion. In conclusion, by interference with V-ATPase, archazolid significantly affects the secretion of cytokines due to accumulation at the ER which might be of relevance when using these agents for cancer therapy.
authors.affiliation: Institute of Pharmacy, Friedrich Schiller University Jena, Philosophenweg 14, 07743 Jena, Germany.
authors.forename: Olga
authors.initials: O
authors.lastname: Scherer
authors.affiliation: Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors.forename: Heinrich
authors.initials: H
authors.lastname: Steinmetz
authors.affiliation: Leibniz Institute for Age Research - Fritz Lipmann Institute, Jena, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Kaether
authors.affiliation: Institute of Transfusion Medicine, University Hospital Jena, Jena, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Weinigel
authors.affiliation: Institute of Transfusion Medicine, University Hospital Jena, Jena, Germany.
authors.forename: Dagmar
authors.initials: D
authors.lastname: Barz
authors.affiliation: Johannes Gutenberg University, Mainz, Germany.
authors.forename: Hartmut
authors.initials: H
authors.lastname: Kleinert
authors.affiliation: Kekulé-Institut für Organische Chemie und Biochemie der Rheinischen Friedrich-Wilhelms-Universität Bonn, Bonn, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Menche
authors.affiliation: Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research and Pharmazeutical Biotechnology, Saarland University, Saarbrücken, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Müller
authors.affiliation: Institute of Pharmacy, Friedrich Schiller University Jena, Philosophenweg 14, 07743 Jena, Germany.
authors.forename: Carlo
authors.initials: C
authors.lastname: Pergola
authors.affiliation: Institute of Pharmacy, Friedrich Schiller University Jena, Philosophenweg 14, 07743 Jena, Germany. Electronic address: oliver.werz@uni-jena.de.
authors.forename: Oliver
authors.initials: O
authors.lastname: Werz
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D016207:Cytokines / Q000378:metabolism*; D017931:DNA Primers; D004305:Dose-Response Relationship, Drug; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D006801:Humans; D018942:Macrolides / Q000494:pharmacology*; D008856:Microscopy, Fluorescence; D009000:Monocytes / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D010766:Phosphorylation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D025262:Vacuolar Proton-Translocating ATPases / Q000378:metabolism*
chemical_list: D016207:Cytokines; D017931:DNA Primers; D018942:Macrolides; D025262:Vacuolar Proton-Translocating ATPases
keywords: Archazolid; Cytokines; Inflammation; Interleukin; Monocytes; Vacuolar-type H(+)-ATPase