title: Multi parameter in vitro testing of ratjadone using flow cytometry.
abstract: Ratjadone, isolated from the myxobacterium Sorangium cellulosum, belongs to the family of so-called orphan ligands, which includes leptomycin, callystatin and other compounds. In previous screening tests, ratjadone revealed a growth inhibitory effect against bacteria, yeast and human cancer cells. Following these first results, ratjadone was tested on several human tumour cell lines (Jurkat, HepG2, U87-MG) and, as a control, on a non-tumour cell line (RLC18) for its mode of action. The cell analysis was carried out by flow cytometry. This comprised cell density measurements, live-dead analysis, cell-cycle analysis and detection of apoptosis. First experiments confirmed the growth inhibitory effect on any chosen tumour cell line. Following these results a dose effect relationship was monitored, confirming the high effectiveness of ratjadone against cell growth at nanomolar concentration. Cell cycle analysis has shown that ratjadone intervenes in the cell cycle by arresting the cells in G1-phase. Biological testing of additional ratjadone derivatives with changed configuration and stereochemistry, identified the pharmacophoric site of the molecule.
authors.affiliation: Institut für Technische Chemie, Universität Hannover, Callinstrasse 3, 30167, Hannover, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Burzlaff
authors.forename: M
authors.initials: M
authors.lastname: Kalesse
authors.forename: C
authors.initials: C
authors.lastname: Kasper
authors.forename: T
authors.initials: T
authors.lastname: Scheper
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D004354:Drug Screening Assays, Antitumor / Q000379:methods; D005434:Flow Cytometry; D006801:Humans; D019169:Jurkat Cells; D011753:Pyrones / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D011753:Pyrones; C429103:ratjadone