α,β-Unsaturated Carbonyl System of Chalcone-Based Derivatives Is Responsible for Broad Inhibition of Proteasomal Activity and Preferential Killing of Human Papilloma Virus (HPV) Positive Cervical Cancer Cells

• Published in: Journal of medicinal chemistry 2011-01, Vol.54 (2), p.449-456
• Main Authors: Bazzaro, Martina, Anchoori, Ravi K, Mudiam, Mohana Krishna R, Issaenko, Olga, Kumar, Srinivas, Karanam, Balasubramanyam, Lin, Zhenhua, Isaksson Vogel, Rachel, Gavioli, Riccardo, Destro, Federica, Ferretti, Valeria, Roden, Richard B. S, Khan, Saeed R
• Format: Article
• Language: English
• Subjects: Antineoplastic Agents - chemical synthesis; Antineoplastic Agents - chemistry; Antineoplastic Agents - pharmacology; Apoptosis - drug effects; Cell Line, Tumor; Cell Proliferation - drug effects; Cell Survival - drug effects; Cell Transformation, Viral; Chalcones - chemical synthesis; Chalcones - chemistry; Chalcones - pharmacology; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Drug Synergism; Female; Humans; Models, Molecular; Papillomaviridae; Proteasome Inhibitors; Structure-Activity Relationship; Uterine Cervical Neoplasms - pathology; Uterine Cervical Neoplasms - virology
• ISSN: 0022-2623; 1520-4804
• DOI: 10.1021/jm100589p

Proteasome inhibitors have potential for the treatment of cervical cancer. We describe the synthesis and biological characterization of a new series of 1,3-diphenylpropen-1-one (chalcone) based derivatives lacking the boronic acid moieties of the previously reported chalcone-based proteasome inhibitor 3,5-bis(4-boronic acid benzylidene)-1-methylpiperidin-4-one and bearing a variety of amino acid substitutions on the amino group of the 4-piperidone. Our lead compound 2 (RA-1) inhibits proteasomal activity and has improved dose-dependent antiproliferative and proapoptotic properties in cervical cancer cells containing human papillomavirus. Further, it induces synergistic killing of cervical cancer cell lines when tested in combination with an FDA approved proteasome inhibitor. Exploration of the potential mechanism of proteasomal inhibition by our lead compound using in silico docking studies suggests that the carbonyl group of its oxopiperidine moiety is susceptible to nucleophilic attack by the γ-hydroxythreonine side chain within the catalytic sites of the proteasome.