Preclinical evaluation of DO3A-Act-AQ: a polyazamacrocyclic monomeric anthraquinone derivative as a theranostic agent

Mol Pharm. 2014 Feb 3;11(2):445-56. doi: 10.1021/mp4004089. Epub 2014 Jan 2.

Abstract

An anthraquinone conjugated macrocyclic chelating agent, 2,2',2″-(10-(2-(9,10-dioxo-9,10-dihydroanthracen-1-ylamino)-2-oxoethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid or DO3A-Act-AQ, was synthesized by reacting trisubstituted cyclen (DO3A) with 2-chloro-N-(9,10-dioxo-9,10-dihydro-anthracen-1-yl)-acetamide and radiolabeled with (68)GaCl3 in 84% efficiency and a specific activity of 4.62 MBq/nmol. The IC50 value for BMG-1 cells was 0.1 mM, while the same concentration of DO3A-Act-AQ rendered no significant toxicity in HEK cells. The exposure of BMG-1 cells with 0.1 mM DO3A-Act-AQ displayed a time-dependent increase in apoptosis (40.7% at 4 h and 53% at 24 h), and the effect was 2.8- and 3.6-fold % higher as seen in HEK cells. An increase in S-phase cell population suggested S-phase arrest concomitant with induction of apoptosis in BMG-1 cells reaching to 4.5 times after 24 h with respect to control cells. DNA binding studies on CT-DNA (calf thymus) revealed a quenching pattern in the presence of DO3A-Act-AQ (10-70 μM), and the Stern-Volmer quenching constant was 2.4157 × 10(6) L mol(-1), indicative of strong binding with ds-DNA. A decrease in the positive and negative bands of CT-DNA was seen at 278 nm and 240 nm, respectively, on addition of 0.05 mM of DO3A-Act-AQ in CD studies. (68)Ga-DO3A-Act-AQ was stable in vitro in both PBS and human serum for at least 2 h. The in vivo blood kinetics study performed on normal rabbits indicated fast clearance with t1/2(F) = 40 ± 0.3 min and t1/2(S) = 3 h 30 min ± 0.1 min. Ex vivo biodistribution analysis displayed a favorable tumor-to-muscle ratio of 8.4 after 2 h in athymic nude mice xenografted with BMG-1 cells, suggesting the specificity of (68)Ga-DO3A-Act-AQ toward tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anthraquinones / chemistry
  • Anthraquinones / pharmacology
  • Anthraquinones / therapeutic use*
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology
  • Antineoplastic Agents / therapeutic use
  • Brain Neoplasms / diagnosis*
  • Brain Neoplasms / therapy*
  • Cell Cycle / drug effects
  • Cell Line, Tumor
  • Circular Dichroism
  • HEK293 Cells
  • Heterocyclic Compounds, 1-Ring / chemistry
  • Heterocyclic Compounds, 1-Ring / pharmacology
  • Heterocyclic Compounds, 1-Ring / therapeutic use*
  • Humans
  • Mice
  • Mice, Nude
  • Rabbits
  • Tissue Distribution

Substances

  • 2,2',2''-(10-(2-(9,10-dioxo-9,10-dihydroanthracen-1-ylamino)-2-oxoethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid
  • Anthraquinones
  • Antineoplastic Agents
  • Heterocyclic Compounds, 1-Ring
  • 9,10-anthraquinone