title: Discovery and characterization of Isofistularin-3, a marine brominated alkaloid, as a new DNA demethylating agent inducing cell cycle arrest and sensitization to TRAIL in cancer cells.
abstract: We characterized the brominated alkaloid Isofistularin-3 (Iso-3), from the marine sponge Aplysina aerophoba, as a new DNA methyltransferase (DNMT)1 inhibitor. Docking analysis confirmed our in vitro DNMT inhibition data and revealed binding of Iso-3 within the DNA binding site of DNMT1. Subsequent increased expression of tumor suppressor gene aryl hydrocarbon receptor (AHR) could be correlated to decreased methylation of CpG sites within the essential Sp1 regulatory region of its promoter. Iso-3 induced growth arrest of cancer cells in G0/G1 concomitant with increased p21 and p27 expression and reduced cyclin E1, PCNA and c-myc levels. Reduced proliferation was accompanied by morphological changes typical of autophagy revealed by fluorescent and transmission electron microscopy and validated by LC3I-II conversion. Furthermore, Iso-3 strongly synergized with tumor-necrosis-factor related apoptosis inducing ligand (TRAIL) in RAJI [combination index (CI) = 0.22] and U-937 cells (CI = 0.21) and increased TRAIL-induced apoptosis via a mechanism involving reduction of survivin expression but not of Bcl-2 family proteins nor X-linked inhibitor of apoptosis protein (XIAP). Iso-3 treatment decreased FLIPL expression and triggered activation of endoplasmatic reticulum (ER) stress with increased GRP78 expression, eventually inducing TRAIL receptor death receptor (DR)5 surface expression. Importantly, as a potential candidate for further anticancer drug development, Iso-3 reduced the viability, colony and in vivo tumor forming potential without affecting the viability of PBMCs from healthy donors or zebrafish development.
authors.affiliation: Laboratoire de Biologie Moléculaire et Cellulaire du Cancer, Hôpital Kirchberg, Lëtzebuerg, Luxembourg.
authors.forename: Cristina
authors.initials: C
authors.lastname: Florean
authors.affiliation: Laboratoire de Biologie Moléculaire et Cellulaire du Cancer, Hôpital Kirchberg, Lëtzebuerg, Luxembourg.
authors.forename: Michael
authors.initials: M
authors.lastname: Schnekenburger
authors.affiliation: Department of Pharmacy, Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Gwanak-gu, Korea.
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Pharmacy, Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Gwanak-gu, Korea.
authors.forename: Kyung Rok
authors.initials: KR
authors.lastname: Kim
authors.affiliation: Department of Pharmacy, Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Gwanak-gu, Korea.
authors.forename: Aloran
authors.initials: A
authors.lastname: Mazumder
authors.affiliation: Department of Pharmacy, Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Gwanak-gu, Korea.
authors.forename: Sungmi
authors.initials: S
authors.lastname: Song
authors.affiliation: Department of Pharmacy, Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Gwanak-gu, Korea.
authors.forename: Jae-Myun
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Laboratoire de Biologie Moléculaire et Cellulaire du Cancer, Hôpital Kirchberg, Lëtzebuerg, Luxembourg.
authors.forename: Cindy
authors.initials: C
authors.lastname: Grandjenette
authors.affiliation: SNU-Harvard Neurovascular Protection Center, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Gwanak-gu, Korea.
authors.forename: Jeoung-Gyun
authors.initials: JG
authors.lastname: Kim
authors.affiliation: SNU-Harvard Neurovascular Protection Center, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Gwanak-gu, Korea.
authors.forename: Ah-Young
authors.initials: AY
authors.lastname: Yoon
authors.affiliation: Laboratoire de Biologie Moléculaire et Cellulaire du Cancer, Hôpital Kirchberg, Lëtzebuerg, Luxembourg.
authors.forename: Mario
authors.initials: M
authors.lastname: Dicato
authors.affiliation: SNU-Harvard Neurovascular Protection Center, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Gwanak-gu, Korea.
authors.forename: Kyu-Won
authors.initials: KW
authors.lastname: Kim
authors.affiliation: Faculté de Médecine, Université de Lorraine, Nancy, France.
authors.forename: Christo
authors.initials: C
authors.lastname: Christov
authors.affiliation: Department of Pharmacy, Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Gwanak-gu, Korea.
authors.forename: Byung-Woo
authors.initials: BW
authors.lastname: Han
authors.affiliation: Institut für Pharmazeutische Biologie und Biotechnologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Proksch
authors.affiliation: Department of Pharmacy, Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Gwanak-gu, Korea.
authors.forename: Marc
authors.initials: M
authors.lastname: Diederich
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000737:chemistry / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D014408:Biomarkers, Tumor; D059447:Cell Cycle Checkpoints / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D019175:DNA Methylation / Q000187:drug effects*; D055808:Drug Discovery; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D000091342:Endoplasmic Reticulum Chaperone BiP; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D011161:Porifera / Q000737:chemistry; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D015027:Zebrafish / Q000254:growth & development* / Q000378:metabolism
chemical_list: D000470:Alkaloids; D018906:Antineoplastic Agents, Alkylating; D014408:Biomarkers, Tumor; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505639:TNFRSF10B protein, human; C505653:TNFSF10 protein, human; C000626294:isofistularin-3
keywords: DNMT inhibitor; TSG hypermethylation; autophagy; cell cycle arrest; leukemia