title: Induction of reactive oxygen species-mediated autophagy by a novel microtubule-modulating agent.
abstract: Autophagy is being increasingly implicated in both cell survival and death. However, the intricate relationships between drug-induced autophagy and apoptosis remain elusive. Here we demonstrate that a tubulin-binding noscapine analog, (R)-9-bromo-5-((S)-4,5-dimethoxy-1,3-dihydroisobenzofuran-1-yl)-4-methoxy-6-methyl-5,6,7,8-tetrahydro-[1,3]-di-oxolo[4,5-g]isoquinoline (Red-Br-nos), exerts a novel autophagic response followed by apoptotic cell death in human prostate cancer PC-3 cells. Red-Br-nos-induced autophagy was an early event detectable within 12 h that displayed a wide array of characteristic features including double membranous vacuoles with entrapped organelles, acidic vesicular organelles, and increased expression of LC3-II and beclin-1. Red-Br-nos-triggered release of reactive oxygen species (ROS) and attenuation of ROS by tiron, a ROS scavenger, reduced the sub-G(1) population suggesting ROS-dependent apoptosis. Abrogation of ROS also reduced autophagy indicating that ROS triggers autophagy. Pharmacological and genetic approaches to inhibit autophagy uncovered the protective role of Red-Br-nos-induced autophagy in PC-3 cells. Direct effects of the drug on mitochondria viz. disruption of normal cristae architecture and dissipation of mitochondrial transmembrane potential revealed a functional link between ROS generation, autophagy, and apoptosis induction. This is the first report to demonstrate the protective role of ROS-mediated autophagy and induction of caspase-independent ROS-dependent apoptosis in PC-3 cells by Red-Br-nos, a member of the noscapinoid family of microtubule-modulating anticancer agents.
authors.affiliation: Department of Biology, Georgia State University, Atlanta, Georgia 30303, USA.
authors.forename: Prasanthi
authors.initials: P
authors.lastname: Karna
authors.forename: Susu
authors.initials: S
authors.lastname: Zughaier
authors.forename: Vaishali
authors.initials: V
authors.lastname: Pannu
authors.forename: Robert
authors.initials: R
authors.lastname: Simmons
authors.forename: Satya
authors.initials: S
authors.lastname: Narayan
authors.forename: Ritu
authors.initials: R
authors.lastname: Aneja
mesh_terms: D021581:Active Transport, Cell Nucleus; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis; D001343:Autophagy; D045744:Cell Line, Tumor; D049452:Green Fluorescent Proteins / Q000737:chemistry; D006801:Humans; D008564:Membrane Potentials; D008856:Microscopy, Fluorescence / Q000379:methods; D008870:Microtubules / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism; D008954:Models, Biological; D009665:Noscapine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D017382:Reactive Oxygen Species; D050257:Tubulin Modulators / Q000378:metabolism*
chemical_list: C550328:9-bromo-5-(4,5-dimethoxy-1,3-dihydroisobenzofuran-1-yl)-4-methoxy-6-methyl-5,6,7,8-tetrahydro-(1,3)-dioxolo(4,5-g)isoquinoline; D000970:Antineoplastic Agents; D017382:Reactive Oxygen Species; D050257:Tubulin Modulators; D049452:Green Fluorescent Proteins; D009665:Noscapine
references.citation: Antioxid Redox Signal. 2009 Apr;11(4):777-90
references.pmid: 18828708
references.citation: J Biol Chem. 2001 Apr 13;276(15):12030-4
references.pmid: 11134038
references.citation: Cell. 2007 Jun 1;129(5):983-97
references.pmid: 17540177
references.citation: Cancer Res. 2008 Mar 1;68(5):1495-503
references.pmid: 18316614
references.citation: Apoptosis. 2008 Jan;13(1):1-9
references.pmid: 17990121
references.citation: DNA Cell Biol. 2007 Oct;26(10):713-20
references.pmid: 17824834
references.citation: FASEB J. 2001 Oct;15(12):2286-7
references.pmid: 11511528
references.citation: Cell Death Differ. 2004 Apr;11(4):448-57
references.pmid: 14713959
references.citation: Cancer Res. 2003 May 1;63(9):2103-8
references.pmid: 12727826
references.citation: Cell Death Differ. 2005 Oct;12(10):1297-309
references.pmid: 15905882
references.citation: Dev Cell. 2002 Jan;2(1):55-67
references.pmid: 11782314
references.citation: Proc Natl Acad Sci U S A. 2004 Dec 28;101(52):18030-5
references.pmid: 15596714
references.citation: Mol Cancer Ther. 2009 Oct;8(10):2914-25
references.pmid: 19808980
references.citation: J Biol Chem. 2006 Jul 14;281(28):19179-87
references.pmid: 16702227
references.citation: Nat Rev Mol Cell Biol. 2008 Jul;9(7):532-42
references.pmid: 18568041
references.citation: J Cell Biol. 1999 Oct 18;147(2):435-46
references.pmid: 10525546
references.citation: Biochem Biophys Res Commun. 1993 Nov 30;197(1):40-5
references.pmid: 8250945
references.citation: J Biol Chem. 2000 Jan 14;275(2):992-8
references.pmid: 10625637
references.citation: J Biol Chem. 2004 Jun 11;279(24):24911-4
references.pmid: 15073175
references.citation: Anal Biochem. 1983 Oct 1;134(1):111-6
references.pmid: 6660480
references.citation: Cell Death Differ. 2009 Jan;16(1):1-2
references.pmid: 19079285
references.citation: Nat Rev Mol Cell Biol. 2005 Mar;6(3):268-75
references.pmid: 15714200
references.citation: Biochem Pharmacol. 2004 Dec 15;68(12):2435-41
references.pmid: 15548390
references.citation: Oncogene. 2008 Jan 31;27(6):831-8
references.pmid: 17637738
references.citation: Nat Cell Biol. 2008 Jun;10(6):637-9
references.pmid: 18521069
references.citation: Cancer Metastasis Rev. 2006 Dec;25(4):695-705
references.pmid: 17160708
references.citation: Mol Pharmacol. 2007 Jan;71(1):101-11
references.pmid: 17035597
references.citation: Genes Dev. 2007 Jun 1;21(11):1367-81
references.pmid: 17510285
references.citation: Dev Cell. 2004 Apr;6(4):463-77
references.pmid: 15068787
references.citation: Cancer Chemother Pharmacol. 2005 May;55(5):461-5
references.pmid: 15690203
references.citation: Autophagy. 2008 May;4(4):409-15
references.pmid: 18227645
references.citation: Proc Natl Acad Sci U S A. 2006 Mar 28;103(13):4952-7
references.pmid: 16547133
references.citation: Cancer Res. 2006 Mar 15;66(6):2885-8
references.pmid: 16540632
references.citation: Nat Rev Mol Cell Biol. 2008 Dec;9(12):1004-10
references.pmid: 18971948
references.citation: Cancer Res. 2001 Jan 15;61(2):439-44
references.pmid: 11212227
references.citation: Cell. 2005 Jan 28;120(2):159-62
references.pmid: 15680321
references.citation: Blood. 2006 Mar 15;107(6):2486-92
references.pmid: 16282340
references.citation: Carcinogenesis. 1996 Aug;17(8):1595-607
references.pmid: 8761415
references.citation: Mol Pharmacol. 2003 Apr;63(4):799-807
references.pmid: 12644580
references.citation: J Biol Chem. 2002 May 10;277(19):17200-8
references.pmid: 11864974
references.citation: Cancer Res. 2009 Jan 15;69(2):700-8
references.pmid: 19147587
references.citation: Nat Rev Mol Cell Biol. 2007 Sep;8(9):741-52
references.pmid: 17717517
references.citation: Cell. 2005 Sep 23;122(6):927-39
references.pmid: 16179260
references.citation: J Mol Cell Cardiol. 1997 Sep;29(9):2571-83
references.pmid: 9299379
references.citation: Autophagy. 2008 Feb;4(2):246-8
references.pmid: 18094624
references.citation: Cancer Res. 2004 Jun 15;64(12):4286-93
references.pmid: 15205343
references.citation: Cancer Res. 2006 Apr 1;66(7):3782-91
references.pmid: 16585205
references.citation: EMBO J. 2007 Apr 4;26(7):1749-60
references.pmid: 17347651
references.citation: Trends Cell Biol. 2007 Sep;17(9):422-7
references.pmid: 17804237
references.citation: Mol Cancer Ther. 2006 Sep;5(9):2366-77
references.pmid: 16985071
references.citation: Oncogene. 2008 Dec;27 Suppl 1:S137-48
references.pmid: 19641499
references.citation: Anticancer Drugs. 2004 Nov;15(10):929-46
references.pmid: 15514562
references.citation: Nature. 1999 Dec 9;402(6762):672-6
references.pmid: 10604474
references.citation: J Histochem Cytochem. 1997 Sep;45(9):1255-64
references.pmid: 9283613
references.citation: Autophagy. 2009 Jan;5(1):114-6
references.pmid: 19001857
references.citation: EMBO J. 2000 Nov 1;19(21):5720-8
references.pmid: 11060023
references.citation: J Clin Invest. 2005 Oct;115(10):2679-88
references.pmid: 16200202
references.citation: Biochem J. 2003 Dec 15;376(Pt 3):577-86
references.pmid: 12967324
references.citation: Autophagy. 2006 Apr-Jun;2(2):85-90
references.pmid: 16874083