{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T00:50:43Z","timestamp":1773103843785,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2018,4,30]],"date-time":"2018-04-30T00:00:00Z","timestamp":1525046400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000001","name":"Alberta Cancer Foundation","doi-asserted-by":"publisher","award":["26603"],"award-info":[{"award-number":["26603"]}],"id":[{"id":"10.13039\/501100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The DNA excision repair protein ERCC-1-DNA repair endonuclease XPF (ERCC1-XPF) is a heterodimeric endonuclease essential for the nucleotide excision repair (NER) DNA repair pathway. Although its activity is required to maintain genome integrity in healthy cells, ERCC1-XPF can counteract the effect of DNA-damaging therapies such as platinum-based chemotherapy in cancer cells. Therefore, a promising approach to enhance the effect of these therapies is to combine their use with small molecules, which can inhibit the repair mechanisms in cancer cells. Currently, there are no structures available for the catalytic site of the human ERCC1-XPF, which performs the metal-mediated cleavage of a DNA damaged strand at 5\u2032. We adopted a homology modeling strategy to build a structural model of the human XPF nuclease domain which contained the active site and to extract dominant conformations of the domain using molecular dynamics simulations followed by clustering of the trajectory. We investigated the binding modes of known small molecule inhibitors targeting the active site to build a pharmacophore model. We then performed a virtual screening of the ZINC Is Not Commercial 15 (ZINC15) database to identify new ERCC1-XPF endonuclease inhibitors. Our work provides structural insights regarding the binding mode of small molecules targeting the ERCC1-XPF active site that can be used to rationally optimize such compounds. We also propose a set of new potential DNA repair inhibitors to be considered for combination cancer therapy strategies.<\/jats:p>","DOI":"10.3390\/ijms19051328","type":"journal-article","created":{"date-parts":[[2018,4,30]],"date-time":"2018-04-30T03:45:49Z","timestamp":1525059949000},"page":"1328","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Computational Characterization of Small Molecules Binding to the Human XPF Active Site and Virtual Screening to Identify Potential New DNA Repair Inhibitors Targeting the ERCC1-XPF Endonuclease"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8299-1976","authenticated-orcid":false,"given":"Francesco","family":"Gentile","sequence":"first","affiliation":[{"name":"Department of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Khaled H.","family":"Barakat","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 2H1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9976-0429","authenticated-orcid":false,"given":"Jack A.","family":"Tuszynski","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada"},{"name":"Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada"},{"name":"Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Torino, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"620","DOI":"10.1016\/j.dnarep.2013.04.015","article-title":"DNA repair mechanisms in dividing and non-dividing cells","volume":"12","author":"Iyama","year":"2013","journal-title":"DNA Repair"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1016\/S0960-9822(99)80118-3","article-title":"Defective repair of cisplatin-induced DNA damage caused by reduced XPA protein in testicular germ cell tumours","volume":"9","author":"Masters","year":"1999","journal-title":"Curr. 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