To better define the possible mechanism of action of compounds, we also examined their dose-dependent effect on topoisomerases, as HU-331 has been proposed to be a catalytic inhibitor

CBL0137 of topoisomerase II. We tested their ability to directly inhibit topoisomerases in cleavage assays demonstrating that our derivatives are not able to poison the nuclear enzymes. To conclude, the analyses of the present study have revealed that the synthesized quinine V has the potential to induce apoptosis in M14 cancer cell line in vitro and it is very important to note that this compound additionally has the ability to inhibit the expression of the antiapoptotic protein XIAP, a regulatory protein that suppresses apoptosis cell death by binding the caspase click here proteins [30, 31]. On the light of interesting pharmacological results, a more extensive medicinal chemistry program has been engaged to consolidate the series and identify lead GW786034 research buy candidates for the design of more potent antitumor agents based on 2-hydroxyquinone skeleton which in turn should afford a better

understanding of biological mechanisms regulating apoptosis. Acknowledgement We are grateful to Dermofarma Italia, Benevento, for financial support. The Topoisomerase test was supported by grant of Associazione Italiana per la Ricerca sulCancro, Milan, Italy, [IG 10184]. References 1. Yu CC, Wu PJ, Hsu JL, Ho YF, Hsu LC, Chang YJ, Chang HS, Chen IS, Guh JH: Ardisianone, a natural Org 27569 benzoquinone, efficiently induces apoptosis in human hormone-refractory prostate cancers through mitochondrial

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