title: Cereblon is a direct protein target for immunomodulatory and antiproliferative activities of lenalidomide and pomalidomide.
abstract: Thalidomide and the immunomodulatory drug, lenalidomide, are therapeutically active in hematological malignancies. The ubiquitously expressed E3 ligase protein cereblon (CRBN) has been identified as the primary teratogenic target of thalidomide. Our studies demonstrate that thalidomide, lenalidomide and another immunomodulatory drug, pomalidomide, bound endogenous CRBN and recombinant CRBN-DNA damage binding protein-1 (DDB1) complexes. CRBN mediated antiproliferative activities of lenalidomide and pomalidomide in myeloma cells, as well as lenalidomide- and pomalidomide-induced cytokine production in T cells. Lenalidomide and pomalidomide inhibited autoubiquitination of CRBN in HEK293T cells expressing thalidomide-binding competent wild-type CRBN, but not thalidomide-binding defective CRBN(YW/AA). Overexpression of CRBN wild-type protein, but not CRBN(YW/AA) mutant protein, in KMS12 myeloma cells, amplified pomalidomide-mediated reductions in c-myc and IRF4 expression and increases in p21(WAF-1) expression. Long-term selection for lenalidomide resistance in H929 myeloma cell lines was accompanied by a reduction in CRBN, while in DF15R myeloma cells resistant to both pomalidomide and lenalidomide, CRBN protein was undetectable. Our biophysical, biochemical and gene silencing studies show that CRBN is a proximate, therapeutically important molecular target of lenalidomide and pomalidomide.
authors.affiliation: Celgene, San Diego, CA 92121, USA. alopez@celgene.com
authors.forename: A
authors.initials: A
authors.lastname: Lopez-Girona
authors.forename: D
authors.initials: D
authors.lastname: Mendy
authors.forename: T
authors.initials: T
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Miller
authors.forename: A K
authors.initials: AK
authors.lastname: Gandhi
authors.forename: J
authors.initials: J
authors.lastname: Kang
authors.forename: S
authors.initials: S
authors.lastname: Karasawa
authors.forename: G
authors.initials: G
authors.lastname: Carmel
authors.forename: P
authors.initials: P
authors.lastname: Jackson
authors.forename: M
authors.initials: M
authors.lastname: Abbasian
authors.forename: A
authors.initials: A
authors.lastname: Mahmoudi
authors.forename: B
authors.initials: B
authors.lastname: Cathers
authors.forename: E
authors.initials: E
authors.lastname: Rychak
authors.forename: S
authors.initials: S
authors.lastname: Gaidarova
authors.forename: R
authors.initials: R
authors.lastname: Chen
authors.forename: P H
authors.initials: PH
authors.lastname: Schafer
authors.forename: H
authors.initials: H
authors.lastname: Handa
authors.forename: T O
authors.initials: TO
authors.lastname: Daniel
authors.forename: J F
authors.initials: JF
authors.lastname: Evans
authors.forename: R
authors.initials: R
authors.lastname: Chopra
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D057809:HEK293 Cells; D006801:Humans; D000077269:Lenalidomide; D010447:Peptide Hydrolases / Q000187:drug effects*; D013792:Thalidomide / Q000031:analogs & derivatives* / Q000494:pharmacology; D044767:Ubiquitin-Protein Ligases; D054875:Ubiquitination
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000276:Adjuvants, Immunologic; D000970:Antineoplastic Agents; C502543:CRBN protein, human; D013792:Thalidomide; C467566:pomalidomide; D044767:Ubiquitin-Protein Ligases; D010447:Peptide Hydrolases; D000077269:Lenalidomide