title: Calcium-dependent modulation of poly(ADP-ribose) polymerase-1 alters cellular metabolism and DNA repair.
abstract: After genotoxic stress poly(ADP-ribose) polymerase-1 (PARP-1) can be hyperactivated, causing (ADP-ribosyl)ation of nuclear proteins (including itself), resulting in NAD(+) and ATP depletion and cell death. Mechanisms of PARP-1-mediated cell death and downstream proteolysis remain enigmatic. beta-lapachone (beta-lap) is the first chemotherapeutic agent to elicit a Ca(2+)-mediated cell death by PARP-1 hyperactivation at clinically relevant doses in cancer cells expressing elevated NAD(P)H:quinone oxidoreductase 1 (NQO1) levels. Beta-lap induces the generation of NQO1-dependent reactive oxygen species (ROS), DNA breaks, and triggers Ca(2+)-dependent gamma-H2AX formation and PARP-1 hyperactivation. Subsequent NAD(+) and ATP losses suppress DNA repair and cause cell death. Reduction of PARP-1 activity or Ca(2+) chelation protects cells. Interestingly, Ca(2+) chelation abrogates hydrogen peroxide (H(2)O(2)), but not N-Methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced PARP-1 hyperactivation and cell death. Thus, Ca(2+) appears to be an important co-factor in PARP-1 hyperactivation after ROS-induced DNA damage, which alters cellular metabolism and DNA repair.
authors.affiliation: Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio 44106, USA.
authors.forename: Melissa S
authors.initials: MS
authors.lastname: Bentle
authors.forename: Kathryn E
authors.initials: KE
authors.lastname: Reinicke
authors.forename: Erik A
authors.initials: EA
authors.lastname: Bey
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Spitz
authors.forename: David A
authors.initials: DA
authors.lastname: Boothman
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D016923:Cell Death / Q000187:drug effects; D002614:Chelating Agents / Q000494:pharmacology; D004247:DNA / Q000235:genetics*; D004249:DNA Damage / Q000235:genetics; D004260:DNA Repair / Q000235:genetics*; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D009243:NAD / Q000378:metabolism; D009285:Naphthoquinones / Q000494:pharmacology; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors
chemical_list: D002614:Chelating Agents; D009285:Naphthoquinones; D009243:NAD; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D004533:Egtazic Acid; C014638:beta-lapachone; D000255:Adenosine Triphosphate; D004247:DNA; D006861:Hydrogen Peroxide; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D002118:Calcium