title: Bone-targeted Src SH2 inhibitors block Src cellular activity and osteoclast-mediated resorption.
abstract: Src, a nonreceptor tyrosine kinase, is an important regulator of osteoclast-mediated resorption. We have investigated whether compounds that bind to the Src SH2 domain inhibit Src activity in cells and decrease osteoclast-mediated resorption. Compounds were examined for binding to the Src SH2 domain in vitro using a fluorescence polarization binding assay. Experiments were carried out with compounds demonstrating in vitro binding activity (nmol/L range) to determine if they inhibit Src SH2 binding and Src function in cells, demonstrate blockade of Src signaling, and lack cellular toxicity. Cell-based assays included: (1) a mammalian two-hybrid assay; (2) morphological reversion and growth inhibition of cSrcY527F-transformed cells; and (3) inhibition of cortactin phosphorylation in csk-/- cells. The Src SH2 binding compounds inhibit Src activity in all three of these mechanism-based assays. The compounds described were synthesized to contain nonhydrolyzable phosphotyrosine mimics that bind to bone. These compounds were further tested and found to inhibit rabbit osteoclast-mediated resorption of dentine. These results indicate that compounds that bind to the Src SH2 domain can inhibit Src activity in cells and inhibit osteoclast-mediated resorption.
authors.affiliation: ARIAD Pharmaceuticals Inc., Cambridge, MA 02139, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Violette
authors.forename: W
authors.initials: W
authors.lastname: Guan
authors.forename: C
authors.initials: C
authors.lastname: Bartlett
authors.forename: J A
authors.initials: JA
authors.lastname: Smith
authors.forename: C
authors.initials: C
authors.lastname: Bardelay
authors.forename: E
authors.initials: E
authors.lastname: Antoine
authors.forename: R J
authors.initials: RJ
authors.lastname: Rickles
authors.forename: E
authors.initials: E
authors.lastname: Mandine
authors.forename: M R
authors.initials: MR
authors.lastname: van Schravendijk
authors.forename: S E
authors.initials: SE
authors.lastname: Adams
authors.forename: B A
authors.initials: BA
authors.lastname: Lynch
authors.forename: W C
authors.initials: WC
authors.lastname: Shakespeare
authors.forename: M
authors.initials: M
authors.lastname: Yang
authors.forename: V A
authors.initials: VA
authors.lastname: Jacobsen
authors.forename: C S
authors.initials: CS
authors.lastname: Takeuchi
authors.forename: K J
authors.initials: KJ
authors.lastname: Macek
authors.forename: R S
authors.initials: RS
authors.lastname: Bohacek
authors.forename: D C
authors.initials: DC
authors.lastname: Dalgarno
authors.forename: M
authors.initials: M
authors.lastname: Weigele
authors.forename: D
authors.initials: D
authors.lastname: Lesuisse
authors.forename: T K
authors.initials: TK
authors.lastname: Sawyer
authors.forename: R
authors.initials: R
authors.lastname: Baron
mesh_terms: D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001862:Bone Resorption / Q000378:metabolism*; D002461:Cell Line, Transformed; D003804:Dentin / Q000378:metabolism; D004164:Diphosphonates / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D005347:Fibroblasts / Q000166:cytology; D006801:Humans; D008024:Ligands; D008322:Mammals; D051379:Mice; D008969:Molecular Sequence Data; D010010:Osteoclasts / Q000166:cytology / Q000378:metabolism*; D010024:Osteoporosis / Q000378:metabolism; D011817:Rabbits; D011869:Radioligand Assay; D051381:Rats; D014316:Tritium; D020798:Two-Hybrid System Techniques; D018909:src Homology Domains / Q000502:physiology*; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: C427504:AP21946; C427505:AP22188; C413184:AP22408; C427503:AP22409; D000199:Actins; D004164:Diphosphonates; D004791:Enzyme Inhibitors; D008024:Ligands; D014316:Tritium; D019061:src-Family Kinases