title: Pharmacologic Wnt Inhibition Reduces Proliferation, Survival, and Clonogenicity of Glioblastoma Cells.
abstract: Wingless (Wnt) signaling is an important pathway in gliomagenesis and in the growth of stem-like glioma cells. Using immunohistochemistry to assess the translocation of β-catenin protein, we identified intranuclear staining suggesting Wnt pathway activation in 8 of 43 surgical samples (19%) from adult patients with glioblastoma and in 9 of 30 surgical samples (30%) from pediatric patients with glioblastoma. Wnt activity, evidenced by nuclear β-catenin in our cohort and high expression of its target AXIN2 (axis inhibitor protein 2) in published glioma datasets, was associated with shorter patient survival, although this was not statistically significant. We determined the effects of the porcupine inhibitor LGK974 on 3 glioblastoma cell lines with elevated AXIN2 and found that it reduced Wnt pathway activity by 50% or more, as assessed by T-cell factor luciferase reporters. Wnt inhibition led to suppression of growth, proliferation in cultures, and modest induction of cell death. LGK974 reduced NANOG messenger RNA levels and the fraction of cells expressing the stem cell marker CD133 in neurosphere cultures, induced glial differentiation, and suppressed clonogenicity. These data indicate that LGK974 is a promising new agent that can inhibit the canonical Wnt pathway in vitro, slow tumor growth, and deplete stem-like clonogenic cells, thereby providing further support for targeting Wnt in patients with glioblastoma.
authors.affiliation: From the Division of Neuropathology, Department of Pathology, Johns Hopkins Hospital (UDK, MN, CGE); and Division of Pediatric Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University (MH), Baltimore, Maryland; Anatomical Pathology, St Jude Children Research Hospital, Memphis, Tennessee (BAO); and Department of Neurosurgery, University Medical Center Düsseldorf, Düsseldorf, Germany (UDK, AKS, KK, JM).
authors.forename: Ulf D
authors.initials: UD
authors.lastname: Kahlert
authors.forename: Abigail K
authors.initials: AK
authors.lastname: Suwala
authors.forename: Katharina
authors.initials: K
authors.lastname: Koch
authors.forename: Manabu
authors.initials: M
authors.lastname: Natsumeda
authors.forename: Brent A
authors.initials: BA
authors.lastname: Orr
authors.forename: Masanori
authors.initials: M
authors.lastname: Hayashi
authors.forename: Jarek
authors.initials: J
authors.lastname: Maciaczyk
authors.forename: Charles G
authors.initials: CG
authors.lastname: Eberhart
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects / Q000502:physiology*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002648:Child; D005909:Glioblastoma / Q000235:genetics* / Q000473:pathology; D006801:Humans; D011719:Pyrazines / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology*; D014410:Tumor Stem Cell Assay / Q000379:methods*; D060449:Wnt Signaling Pathway / Q000187:drug effects / Q000502:physiology*
chemical_list: D011719:Pyrazines; D011725:Pyridines; C586458:LGK974