title: Inhibition of the Tcf/beta-catenin complex increases apoptosis and impairs adrenocortical tumor cell proliferation and adrenal steroidogenesis.
abstract: BACKGROUND
  To date, there is no effective therapy for patients with advanced/metastatic adrenocortical cancer (ACC). The activation of the Wnt/beta-catenin signaling is frequent in ACC and this pathway is a promising therapeutic target.
  
  
  OBJECTIVE
  To investigate the effects of the inhibition of the Wnt/beta-catenin in ACC cells.
  
  
  METHODS
  Adrenal (NCI-H295 and Y1) and non-adrenal (HeLa) cell lines were treated with PNU-74654 (5-200 μM) for 24-96 h to assess cell viability (MTS-based assay), apoptosis (Annexin V), expression/localization of beta-catenin (qPCR, immunofluorescence, immunocytochemistry and western blot), expression of beta-catenin target genes (qPCR and western blot), and adrenal steroidogenesis (radioimmunoassay, qPCR and western blot).
  
  
  RESULTS
  In NCI-H295 cells, PNU-74654 significantly decreased cell proliferation 96 h after treatment, increased early and late apoptosis, decreased nuclear beta-catenin accumulation, impaired CTNNB1/beta-catenin expression and increased beta-catenin target genes 48 h after treatment. No effects were observed on HeLa cells. In NCI-H295 cells, PNU-74654 decreased cortisol, testosterone and androstenedione secretion 24 and 48 h after treatment. Additionally, in NCI-H295 cells, PNU-74654 decreased SF1 and CYP21A2 mRNA expression as well as the protein levels of STAR and aldosterone synthase 48 h after treatment. In Y1 cells, PNU-74654 impaired corticosterone secretion 24 h after treatment but did not decrease cell viability.
  
  
  CONCLUSIONS
  Blocking the Tcf/beta-catenin complex inhibits the Wnt/beta-catenin signaling in adrenocortical tumor cells triggering increased apoptosis, decreased cell viability and impairment of adrenal steroidogenesis. These promising findings pave the way for further experiments inhibiting the Wnt/beta-catenin pathway in pre-clinical models of ACC. The inhibition of this pathway may become a promising adjuvant therapy for patients with ACC.
authors.affiliation: Department of Pediatrics, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.
authors.forename: Letícia F
authors.initials: LF
authors.lastname: Leal
authors.affiliation: Department of Pediatrics, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: Bueno
authors.affiliation: Department of Pediatrics, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.|Department of Pediatrics, School of Medicine, Federal University of Uberlandia, Uberlândia, Minas Gerais, Brazil.
authors.forename: Débora C
authors.initials: DC
authors.lastname: Gomes
authors.affiliation: Department of Pediatrics, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.
authors.forename: Rafael
authors.initials: R
authors.lastname: Abduch
authors.affiliation: Department of Internal Medicine, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.
authors.forename: Margaret
authors.initials: M
authors.lastname: de Castro
authors.affiliation: Department of Pediatrics, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.
authors.forename: Sonir R
authors.initials: SR
authors.lastname: Antonini
mesh_terms: D000306:Adrenal Cortex Neoplasms / Q000473:pathology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D011863:Radioimmunoassay; D060888:Real-Time Polymerase Chain Reaction; D051822:T Cell Transcription Factor 1 / Q000037:antagonists & inhibitors*; D060449:Wnt Signaling Pathway / Q000187:drug effects; D051176:beta Catenin / Q000037:antagonists & inhibitors*
chemical_list: D000970:Antineoplastic Agents; D051822:T Cell Transcription Factor 1; C497576:TCF7 protein, human; D051176:beta Catenin
keywords: adrenocortical cancer; apoptosis; beta-catenin; steroidogenesis; targeted therapy