CBR-2092 is a DNA-directed RNA polymerase and DNA topoisomerase inhibitor. CBR-2092 exhibited rifampin-like potency as an inhibitor of RNA polymerase, was an equipotent (balanced) inhibitor of DNA gyrase and DNA topoisomerase IV, and retained activity against a prevalent quinolone-resistant variant. Studies of mutant strains that exhibited reduced susceptibility to CBR-2092 further substantiated RNA polymerase as the primary cellular target of CBR-2092, with DNA gyrase and DNA topoisomerase IV being secondary and tertiary targets, respectively, in strains exhibiting preexisting rifampin resistance.
A-849519 is a reversible inhibitor of MetAP2 that has demonstrated anti-angiogenesis and anticancer activity in a number of in vitro and in vivo models. In this study, we evaluated the anticancer activity of A-849519 in a modified Dunning model of androgen-independent prostate cancer and compared its efficacy with TNP-470, an established MetAP2 inhibitor.