Identification of the first small-molecule inhibitor of the REV7 DNA repair protein interaction

• Published in: Bioorganic & medicinal chemistry Vol. 24; no. 18; pp. 4339 - 4346
• Main Authors: Actis, Marcelo L., Ambaye, Nigus D., Evison, Benjamin J., Shao, Youming, Vanarotti, Murugendra, Inoue, Akira, McDonald, Ezelle T., Kikuchi, Sotaro, Heath, Richard, Hara, Kodai, Hashimoto, Hiroshi, Fujii, Naoaki
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15.09.2016
• Subjects: Antineoplastic Agents - chemical synthesis; Antineoplastic Agents - pharmacology; Chemotherapy; Cisplatin - pharmacology; DNA damage response; DNA Repair; DNA-Binding Proteins - antagonists & inhibitors; DNA-Directed DNA Polymerase; Drug Resistance, Neoplasm; HeLa Cells; High-throughput screening; Humans; Interstrand crosslink repair; Mad2 Proteins - antagonists & inhibitors; Polζ; Protein Binding; Pyrimidinones - chemical synthesis; Pyrimidinones - pharmacology; REV3L; REV7; Structure-Activity Relationship; Thiophenes - chemical synthesis; Thiophenes - pharmacology; PBS; DMSO; DNA damage response; HTS; High-throughput screening; FP; HR; WaterLOGSY; Polζ; BSA; TAMRA; NMR; REV7; Chemotherapy; ICL; AlphaScreen; FBS; HEPES; GB1; REV3L; MBP; TLS; Interstrand crosslink repair; PCR
• ISSN: 0968-0896; 1464-3391; 1464-3391
• DOI: 10.1016/j.bmc.2016.07.026

[Display omitted] DNA interstrand crosslink (ICL) repair (ICLR) has been implicated in the resistance of cancer cells to ICL-inducing chemotherapeutic agents. Despite the clinical significance of ICL-inducing chemotherapy, few studies have focused on developing small-molecule inhibitors for ICLR. The mammalian DNA polymerase ζ, which comprises the catalytic subunit REV3L and the non-catalytic subunit REV7, is essential for ICLR. To identify small-molecule compounds that are mechanistically capable of inhibiting ICLR by targeting REV7, high-throughput screening and structure–activity relationship (SAR) analysis were performed. Compound 1 was identified as an inhibitor of the interaction of REV7 with the REV7-binding sequence of REV3L. Compound 7 (an optimized analog of compound 1) bound directly to REV7 in nuclear magnetic resonance analyses, and inhibited the reactivation of a reporter plasmid containing an ICL in between the promoter and reporter regions. The normalized clonogenic survival of HeLa cells treated with cisplatin and compound 7 was lower than that for cells treated with cisplatin only. These findings indicate that a small-molecule inhibitor of the REV7/REV3L interaction can chemosensitize cells by inhibiting ICLR.