{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T11:22:14Z","timestamp":1781522534020,"version":"3.54.1"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2019,5,8]],"date-time":"2019-05-08T00:00:00Z","timestamp":1557273600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001602","name":"Science Foundation Ireland","doi-asserted-by":"publisher","award":["15\/CDA\/3648"],"award-info":[{"award-number":["15\/CDA\/3648"]}],"id":[{"id":"10.13039\/501100001602","id-type":"DOI","asserted-by":"publisher"}]},{"name":"KRIPIS (European Social Fund \/ Greek National Funds )","award":["NSRF"],"award-info":[{"award-number":["NSRF"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>The anticancer activity of acridone derivatives has attracted increasing interest, therefore, a variety of substituted analogs belonging to this family have been developed and evaluated for their anti-cancer properties. A series of N-alkyl-acridones 1\u20136 and N,N\u2032-dialkyl-9,9\u2032-biacridylidenes 7\u201312 with variable alkyl chains were examined for their topoisomerase I activity at neutral and acidic conditions as well as for their binding capacity to calf thymus and possible radical trapping antioxidant activity. It was found that at a neutral pH, topoisomerase I activity of both classes of compounds was similar, while under acidic conditions, enhanced intercalation was observed. N-alkyl-acridone derivatives 1\u20136 exhibited stronger, dose-dependent, cytotoxic activity against MCF-7 human breast epithelial cancer cells than N,N\u2032-dialkyl-9,9\u2032-biacridylidenes 7\u201312, revealing that conjugation of the heteroaromatic system plays a significant role on the effective distribution of the compound in the intracellular environment. Cellular investigation of long alkyl derivatives against cell migration exhibited 40\u201350% wound healing effects and cytoplasm diffusion, while compounds with shorter alkyl chains were accumulated both in the nucleus and cytoplasm. All N,N\u2032-dialkyl-9,9\u2032-biacridylidenes showed unexpected high scavenging activity towards DPPH or ABTS radicals which may be explained by higher stabilization of radical cations by the extended conjugation of heteroaromatic ring system.<\/jats:p>","DOI":"10.3390\/biom9050177","type":"journal-article","created":{"date-parts":[[2019,5,13]],"date-time":"2019-05-13T03:57:07Z","timestamp":1557719827000},"page":"177","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Assessment of DNA Topoisomerase I Unwinding Activity, Radical Scavenging Capacity, and Inhibition of Breast Cancer Cell Viability of N-alkyl-acridones and N,N\u2032-dialkyl-9,9\u2032-biacridylidenes"],"prefix":"10.3390","volume":"9","author":[{"given":"Marios G.","family":"Krokidis","sequence":"first","affiliation":[{"name":"Institute of Nanoscience and Nanotechnology, N.C.S.R. \u201cDemokritos\u201d, 15310 Agia Paraskevi-Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9717-6130","authenticated-orcid":false,"given":"Zara","family":"Molphy","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences and National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, 9 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleni K.","family":"Efthimiadou","sequence":"additional","affiliation":[{"name":"Institute of Nanoscience and Nanotechnology, N.C.S.R. \u201cDemokritos\u201d, 15310 Agia Paraskevi-Athens, Greece"},{"name":"Department of Chemistry, National and Kapodistrian University of Athens, 15784 Zografou, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marianna","family":"Kokoli","sequence":"additional","affiliation":[{"name":"Institute of Nanoscience and Nanotechnology, N.C.S.R. \u201cDemokritos\u201d, 15310 Agia Paraskevi-Athens, Greece"},{"name":"Department of Chemistry, National and Kapodistrian University of Athens, 15784 Zografou, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6177-7698","authenticated-orcid":false,"given":"Smaragda-Maria","family":"Argyri","sequence":"additional","affiliation":[{"name":"Institute of Nanoscience and Nanotechnology, N.C.S.R. \u201cDemokritos\u201d, 15310 Agia Paraskevi-Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irini","family":"Dousi","sequence":"additional","affiliation":[{"name":"Institute of Nanoscience and Nanotechnology, N.C.S.R. \u201cDemokritos\u201d, 15310 Agia Paraskevi-Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7163-3978","authenticated-orcid":false,"given":"Annalisa","family":"Masi","sequence":"additional","affiliation":[{"name":"ISOF, Consiglio Nazionale delle Ricerche, Via Piero Gobetti 101, 40129 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyriakos","family":"Papadopoulos","sequence":"additional","affiliation":[{"name":"Institute of Nanoscience and Nanotechnology, N.C.S.R. \u201cDemokritos\u201d, 15310 Agia Paraskevi-Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8947-1401","authenticated-orcid":false,"given":"Andrew","family":"Kellett","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences and National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, 9 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2626-2925","authenticated-orcid":false,"given":"Chryssostomos","family":"Chatgilialoglu","sequence":"additional","affiliation":[{"name":"Institute of Nanoscience and Nanotechnology, N.C.S.R. \u201cDemokritos\u201d, 15310 Agia Paraskevi-Athens, Greece"},{"name":"ISOF, Consiglio Nazionale delle Ricerche, Via Piero Gobetti 101, 40129 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,8]]},"reference":[{"key":"ref_1","first-page":"2356","article-title":"Inhibition effects of acridone on the growth of breast cancer cells in vivo","volume":"22","author":"Xia","year":"2018","journal-title":"Eur. 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