Structure-based Discovery of Novel Small Molecule Wnt Signaling Inhibitors by Targeting the Cysteine-rich Domain of Frizzled.
Frizzled is the earliest discovered glycosylated Wnt protein receptor and is critical for the initiation of Wnt signaling. Antagonizing Frizzled is effective in inhibiting the growth of multiple tumor types. The extracellular N terminus of Frizzled contains a conserved cysteine-rich domain that directly interacts with Wnt ligands. Structure-based virtual screening and cell-based assays were used to identify five small molecules that can inhibit canonical Wnt signaling and have low IC50 values in the micromolar range. NMR experiments confirmed that these compounds specifically bind to the Wnt binding site on the Frizzled8 cysteine-rich domain with submicromolar dissociation constants. Our study confirms the feasibility of targeting the Frizzled cysteine-rich domain as an effective way of regulating canonical Wnt signaling. These small molecules can be further optimized into more potent therapeutic agents for regulating abnormal Wnt signaling by targeting Frizzled.
From the Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105.
Ho-Jin
HJ
Lee
From the Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105.
Ju
J
Bao
From the Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105.
Ami
A
Miller
From the Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, the Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095.
Chi
C
Zhang
the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China, and the Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06510.
Jibo
J
Wu
From the Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105.
Yiressy C
YC
Baday
From the Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105.
Cristina
C
Guibao
the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China, and.
Lin
L
Li
the Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06510.
Dianqing
D
Wu
From the Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, the Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, jzheng@jsei.ucla.edu.
Jie J
JJ
Zheng
D016475:3T3 Cells; D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry* / Q000494:pharmacology*; D001665:Binding Sites; D004354:Drug Screening Assays, Antitumor; D051157:Frizzled Receptors / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D057809:HEK293 Cells; D006801:Humans; D051379:Mice; D062105:Molecular Docking Simulation; D019906:Nuclear Magnetic Resonance, Biomolecular; D017434:Protein Structure, Tertiary; D060449:Wnt Signaling Pathway / Q000187:drug effects*
D000970:Antineoplastic Agents; D051157:Frizzled Receptors
Wnt signaling; anticancer drug; drug discovery; molecular docking; nuclear magnetic resonance (NMR)