title: Mutations at the boundary of the hinge and ligand binding domain of the androgen receptor confer increased transactivation function.
abstract: The androgen receptor (AR), a member of the steroid receptor superfamily of nuclear transcription factors, mediates androgen signaling in diverse target tissues. Here we report AR gene mutations identified in human prostate cancer and the autochthonous transgenic adenocarcinoma of the mouse prostate model that colocate to residues (668)QPIF(671) at the boundary of the hinge and ligand-binding domain, resulting in receptors that exhibit 2- to 4-fold increased activity compared with wild-type AR in response to dihydrotestosterone, estradiol, progesterone, adrenal androgens, and the AR antagonist, hydroxyflutamide, without an apparent effect on receptor levels, ligand binding kinetics, or DNA binding. The expression of these or similar variants could explain the emergence of hormone refractory disease in a subset of patients. Homology modeling indicates that amino acid residues (668)QPIF(671) form a ridge bordering a potential protein-protein interaction surface. The naturally occurring AR gene mutations reported in this study result in decreased hydrophobicity of this surface, suggesting that altered receptor-protein interaction mediates the precocious activity of the AR variants.
authors.affiliation: Flinders Cancer Centre, Flinders University and Flinders Medical Centre Adelaide SA 5042, Australia.
authors.forename: G
authors.initials: G
authors.lastname: Buchanan
authors.forename: M
authors.initials: M
authors.lastname: Yang
authors.forename: J M
authors.initials: JM
authors.lastname: Harris
authors.forename: H S
authors.initials: HS
authors.lastname: Nahm
authors.forename: G
authors.initials: G
authors.lastname: Han
authors.forename: N
authors.initials: N
authors.lastname: Moore
authors.forename: J M
authors.initials: JM
authors.lastname: Bentel
authors.forename: R J
authors.initials: RJ
authors.lastname: Matusik
authors.forename: D J
authors.initials: DJ
authors.lastname: Horsfall
authors.forename: V R
authors.initials: VR
authors.lastname: Marshall
authors.forename: N M
authors.initials: NM
authors.lastname: Greenberg
authors.forename: W D
authors.initials: WD
authors.lastname: Tilley
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics; D000726:Androgen Antagonists / Q000494:pharmacology; D000728:Androgens / Q000494:pharmacology; D000818:Animals; D001665:Binding Sites; D019556:COS Cells; D002460:Cell Line; D004247:DNA / Q000378:metabolism; D013196:Dihydrotestosterone / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology; D005485:Flutamide / Q000031:analogs & derivatives* / Q000494:pharmacology; D006801:Humans; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D008958:Models, Molecular; D016296:Mutagenesis; D009154:Mutation; D011374:Progesterone / Q000494:pharmacology; D011471:Prostatic Neoplasms / Q000235:genetics; D017433:Protein Structure, Secondary; D011944:Receptors, Androgen / Q000737:chemistry* / Q000235:genetics* / Q000502:physiology; D013329:Structure-Activity Relationship; D015533:Transcriptional Activation; D014162:Transfection
chemical_list: D000726:Androgen Antagonists; D000728:Androgens; D011944:Receptors, Androgen; D013196:Dihydrotestosterone; C014290:hydroxyflutamide; D011374:Progesterone; D004958:Estradiol; D005485:Flutamide; D004247:DNA