PT - JOURNAL ARTICLE AU - Sonja M. Hampel AU - Antonella Pepe AU - Karin M. Greulich-Bode AU - Sanjay V. Malhotra AU - Anthony P. Reszka AU - Sebastian Veith AU - Petra Boukamp AU - Stephen Neidle TI - Mechanism of the Antiproliferative Activity of Some Naphthalene Diimide G-Quadruplex Ligands AID - 10.1124/mol.112.081075 DP - 2013 Feb 01 TA - Molecular Pharmacology PG - 470--480 VI - 83 IP - 2 4099 - http://molpharm.aspetjournals.org/content/83/2/470.short 4100 - http://molpharm.aspetjournals.org/content/83/2/470.full SO - Mol Pharmacol2013 Feb 01; 83 AB - G-quadruplexes are higher-order nucleic acid structures that can form in G-rich telomeres and promoter regions of oncogenes. Telomeric quadruplex stabilization by small molecules can lead to telomere uncapping, followed by DNA damage response and senescence, as well as chromosomal fusions leading to deregulation of mitosis, followed by apoptosis and downregulation of oncogene expression. We report here on investigations into the mechanism of action of tetra-substituted naphthalene diimide ligands on the basis of cell biologic data together with a National Cancer Institute COMPARE study. We conclude that four principal mechanisms of action are implicated for these compounds: 1) telomere uncapping with subsequent DNA damage response and senescence; 2) inhibition of transcription/translation of oncogenes; 3) genomic instability through telomeric DNA end fusions, resulting in mitotic catastrophe and apoptosis; and 4) induction of chromosomal instability by telomere aggregate formation.