title: Geldanamycin, radicicol, and chimeric inhibitors of the Hsp90 N-terminal ATP binding site.
abstract: Natural products have continued to drive the development of new chemotherapeutics and elucidation of new biological targets for the treatment of disease. Since Whitesell and Neckers' original discovery that geldanamycin does not directly inhibit v-Src, but instead manifests its biological activity through inhibition of the Hsp90 molecular chaperone, additional natural products and natural product derivatives have been identified and developed to inhibit the Hsp90 protein folding machinery. 17-AAG, a geldanamycin analogue, is currently in clinical trials for the treatment of several types of cancer. Recent work has produced improved radicicol analogues that show promising Hsp90 inhibitory activity in vitro. In addition, chimeric molecules of these two natural products are active in vitro and represent a novel class of Hsp90 inhibitors for cancer treatment. In addition to their chemotherapeutic uses, natural product inhibitors and their derivatives have been utilized to probe the biological mechanisms by which Hsp90 inhibition regulates tumor cell growth. As a consequence of these studies, the molecular chaperones have emerged as an exciting new class of therapeutic targets. This review will highlight the utility of the natural products, geldanamycin and radicicol, as well as improved analogues and the activities exhibited by these compounds against various cancer cell lines.
authors.affiliation: Department of Medicinal Chemistry and The Center for Protein Structure and Function, The University of Kansas, 1251 Wescoe Hall Drive, Malott 4070, Lawrence, Kansas 66045-7563, USA.
authors.forename: M Kyle
authors.initials: MK
authors.lastname: Hadden
authors.forename: Donna J
authors.initials: DJ
authors.lastname: Lubbers
authors.forename: Brian S J
authors.initials: BS
authors.lastname: Blagg
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D016227:Benzoquinones / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D001665:Binding Sites; D015195:Drug Design; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006801:Humans; D047029:Lactams, Macrocyclic / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D018942:Macrolides / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D008958:Models, Molecular; D015394:Molecular Structure; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D000903:Antibiotics, Antineoplastic; D016227:Benzoquinones; D018841:HSP90 Heat-Shock Proteins; D047029:Lactams, Macrocyclic; D018942:Macrolides; D000255:Adenosine Triphosphate; C035359:monorden; C001277:geldanamycin