title: Inhibition of Wnt/β-catenin pathway by niclosamide: a therapeutic target for ovarian cancer.
abstract: Objective. The Wnt/β-catenin pathway is known to regulate cellular proliferation and plays a role in chemoresistance. Niclosamide, an FDA approved salicyclamide derivative used for the treatment of tapeworm infections, targets the Wnt/β-catenin pathway. Therefore, the objective of this study was to investigate niclosamide as a potential therapeutic agent for ovarian cancer. Methods. Tumor cells isolated from 34 patients' ascites with primary ovarian cancer were treated with niclosamide (0.1 to 5 μM) ± carboplatin (5 to 150 μM). Cell viability was assessed using the ATP-lite assay. LRP6, Axin 2, Cyclin D1, survivin and cytosolic free β-catenin levels were determined using Western blot analysis. Tumorspheres were treated, and Wnt transcriptional activity was measured by the TOPflash reporter assay. ALDH and CD133 were analyzed by Flow cytometry and IHC. ALDH1A1 and LRP6 were analyzed by IHC in solid tumor and in ascites before and after treatment with niclosamide. Results. Combination treatment produced increased cytotoxicity compared to single agent treatment in 32/34 patient samples. Western blot analysis showed a decrease in Wnt/β-catenin pathway proteins and the expression of target genes. A significant reduction of Wnt/β-catenin signaling was confirmed by TOPflash assay. There was increased staining of ALDH1A1 and LRP6 in ascites compared to solid tumor which decreased after treatment. Conclusion. This study demonstrates that niclosamide is a potent Wnt/β-catenin inhibitor. Targeting the Wnt/β-catenin pathway led to decreased cellular proliferation and increased cell death. These findings warrant further research of this drug and other niclosamide analogs as a treatment option for ovarian cancer.
authors.affiliation: Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, AL, USA. Electronic address: rebecca.arend@gmail.com.
authors.forename: Rebecca C
authors.initials: RC
authors.lastname: Arend
authors.affiliation: Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Angelina I
authors.initials: AI
authors.lastname: Londoño-Joshi
authors.affiliation: Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Rajeev S
authors.initials: RS
authors.lastname: Samant
authors.affiliation: Southern Research Institute, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Yonghe
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Conner
authors.affiliation: Department of Biostatistics, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Bertha
authors.initials: B
authors.lastname: Hidalgo
authors.affiliation: Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Alvarez
authors.affiliation: Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Charles N
authors.initials: CN
authors.lastname: Landen
authors.affiliation: Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: J Michael
authors.initials: JM
authors.lastname: Straughn
authors.affiliation: Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Buchsbaum
mesh_terms: D000071916:AC133 Antigen; D000444:Aldehyde Dehydrogenase / Q000378:metabolism; D015703:Antigens, CD / Q000096:biosynthesis; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D001201:Ascites / Q000378:metabolism / Q000473:pathology; D016190:Carboplatin / Q000008:administration & dosage; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D005260:Female; D006023:Glycoproteins / Q000096:biosynthesis; D006801:Humans; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D009534:Niclosamide / Q000008:administration & dosage / Q000494:pharmacology*; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D010455:Peptides; D060449:Wnt Signaling Pathway / Q000187:drug effects*
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; D009534:Niclosamide; D016190:Carboplatin; D000444:Aldehyde Dehydrogenase
keywords: Cancer stem cells; Chemoresistance; LRP6; Niclosamide; Ovarian cancer; Wnt/β-catenin