Next Article in Journal
Tetrodotoxin Sensitivity of the Vertebrate Cardiac Na+ Current
Next Article in Special Issue
Advancement into the Arctic Region for Bioactive Sponge Secondary Metabolites
Previous Article in Journal
Isolation and Identification of a New Tetrodotoxin-Producing Bacterial Species, Raoultella terrigena, from Hong Kong Marine Puffer Fish Takifugu niphobles
Previous Article in Special Issue
Examination of Marine-Based Cultivation of Three Demosponges for Acquiring Bioactive Marine Natural Products
Open AccessArticle

Neoamphimedine Circumvents Metnase-Enhanced DNA Topoisomerase IIα Activity Through ATP-Competitive Inhibition

Department of Pharmaceutical Sciences, The University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Anschutz Medical Campus, Aurora, CO 80045,USA
Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
Department of Medicine, University of Florida and Shands Health Care System, Gainesville, FL 32610, USA
Author to whom correspondence should be addressed.
Mar. Drugs 2011, 9(11), 2397-2408;
Received: 6 September 2011 / Revised: 8 November 2011 / Accepted: 9 November 2011 / Published: 18 November 2011
(This article belongs to the Special Issue Bioactive Compound from Marine Sponges)
Type IIα DNA topoisomerase (TopoIIα) is among the most important clinical drug targets for the treatment of cancer. Recently, the DNA repair protein Metnase was shown to enhance TopoIIα activity and increase resistance to TopoIIα poisons. Using in vitro DNA decatenation assays we show that neoamphimedine potently inhibits TopoIIα-dependent DNA decatenation in the presence of Metnase. Cell proliferation assays demonstrate that neoamphimedine can inhibit Metnase-enhanced cell growth with an IC50 of 0.5 µM. Additionally, we find that the apparent Km of TopoIIα for ATP increases linearly with higher concentrations of neoamphimedine, indicating ATP-competitive inhibition, which is substantiated by molecular modeling. These findings support the continued development of neoamphimedine as an anticancer agent, particularly in solid tumors that over-express Metnase. View Full-Text
Keywords: neoamphimedine; topoisomerase II; Metnase; cancer therapeutics neoamphimedine; topoisomerase II; Metnase; cancer therapeutics
Show Figures

Graphical abstract

MDPI and ACS Style

Ponder, J.; Yoo, B.H.; Abraham, A.D.; Li, Q.; Ashley, A.K.; Amerin, C.L.; Zhou, Q.; Reid, B.G.; Reigan, P.; Hromas, R.; Nickoloff, J.A.; LaBarbera, D.V. Neoamphimedine Circumvents Metnase-Enhanced DNA Topoisomerase IIα Activity Through ATP-Competitive Inhibition. Mar. Drugs 2011, 9, 2397-2408.

Show more citation formats Show less citations formats

Article Access Map

Only visits after 24 November 2015 are recorded.
Back to TopTop