title: Curcumin is an inhibitor of p300 histone acetylatransferase.
abstract: Histone acetyltransferases (HATs), and p300/CBP in particular, have been implicated in cancer cell growth and survival, and as such, HATs represent novel, therapeutically relevant molecular targets for drug development. In this study, we demonstrate that the small molecule natural product curcumin, whose medicinal properties have long been recognized in India and Southeast Asia, is a selective HAT inhibitor. Furthermore the data indicate that alpha, beta unsaturated carbonyl groups in the curcumin side chain function as Michael reaction sites and that the Michael reaction acceptor functionality of curcumin is required for its HAT-inhibitory activity. In cells, curcumin promoted proteasome-dependent degradation of p300 and the closely related CBP protein without affecting the HATs PCAF or GCN5. In addition to inducing p300 degradation curcumin inhibited the acetyltransferase activity of purified p300 as assessed using either histone H3 or p53 as substrate. Radiolabeled curcumin formed a covalent association with p300, and tetrahydrocurcumin displayed no p300 inhibitory activity, consistent with a Michael reaction-dependent mechanism. Finally, curcumin was able to effectively block histone hyperacetylation in both PC3-M prostate cancer cells and peripheral blood lymphocytes induced by the histone deacetylase inhibitor MS-275. These data thus identify the medicinal natural product curcumin as a novel lead compound for development of possibly therapeutic, p300/CBP-specific HAT inhibitors.
authors.affiliation: Urologic Oncology Branch and Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA.
authors.forename: Monica G
authors.initials: MG
authors.lastname: Marcu
authors.forename: Yun-Jin
authors.initials: YJ
authors.lastname: Jung
authors.forename: Sunmin
authors.initials: S
authors.lastname: Lee
authors.forename: Eun-Joo
authors.initials: EJ
authors.lastname: Chung
authors.forename: Min-Jung
authors.initials: MJ
authors.lastname: Lee
authors.forename: Jane
authors.initials: J
authors.lastname: Trepel
authors.forename: Len
authors.initials: L
authors.lastname: Neckers
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D001549:Benzamides / Q000494:pharmacology; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects*; D003474:Curcumin / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D051548:Histone Acetyltransferases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006801:Humans; D007553:Isotope Labeling; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D011471:Prostatic Neoplasms / Q000473:pathology; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D014157:Transcription Factors / Q000037:antagonists & inhibitors* / Q000378:metabolism; D014407:Tumor Cells, Cultured; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D018797:Cell Cycle Proteins; D003474:Curcumin; D004791:Enzyme Inhibitors; D051548:Histone Acetyltransferases; D046988:Proteasome Endopeptidase Complex; D011725:Pyridines; D014157:Transcription Factors; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor; C118739:entinostat