title: 3D models of epithelial-mesenchymal transition in breast cancer metastasis: high-throughput screening assay development, validation, and pilot screen.
abstract: Despite advancements in therapies developed for the treatment of cancer, patient prognosis and mortality rates have improved minimally, and metastasis remains the primary cause of cancer mortality worldwide. An underlying mechanism promoting metastasis in many types of cancer is epithelial-mesenchymal transition (EMT). Here the authors report a novel 3D model of EMT and metastatic breast cancer suitable for high-throughput screening (HTS) drug discovery. The primary assay incorporates the expression of the prognostic biomarker vimentin, as a luciferase reporter of EMT, in basil-like/triple-negative MDA-MB-231 breast carcinoma spheroids. Using this model, the authors developed a number of known antitumor agents as control modulators of EMT. U0126, PKC412, PF2341066, dasatinib, and axitinib downregulated vimentin expression by 70% to 90% as compared to untreated spheroids. Counterassays were developed to measure spheroid viability and the invasive potential of MDA-MB-231 spheroids after small-molecule treatment and used to confirm hits from primary screening. Finally, the authors conducted a pilot screen to validate this model for HTS using a purified library of marine secondary metabolites. From 230 compounds screened, they obtained a Z' score of 0.64, indicative of an excellent assay, and confirmed 4 hits, including isonaamidine B, papuamine, mycalolide E, and jaspamide. This HTS model demonstrates the potential to identify small-molecule modulators of EMT that could be used to discover novel antimetastatic agents for the treatment of cancer.
authors.affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Denver Anschutz Medial Center, Aurora, CO 80045, USA.
authors.forename: Qun
authors.initials: Q
authors.lastname: Li
authors.forename: Chaoyu
authors.initials: C
authors.lastname: Chen
authors.forename: Amit
authors.initials: A
authors.lastname: Kapadia
authors.forename: Qiong
authors.initials: Q
authors.lastname: Zhou
authors.forename: Mary Kay
authors.initials: MK
authors.lastname: Harper
authors.forename: Jerome
authors.initials: J
authors.lastname: Schaack
authors.forename: Daniel V
authors.initials: DV
authors.lastname: LaBarbera
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D001688:Biological Products / Q000494:pharmacology; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D047630:Depsipeptides / Q000737:chemistry / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D058750:Epithelial-Mesenchymal Transition / Q000187:drug effects / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D057809:HEK293 Cells; D057166:High-Throughput Screening Assays; D006801:Humans; D007093:Imidazoles / Q000737:chemistry / Q000494:pharmacology; D008954:Models, Biological; D009362:Neoplasm Metastasis; D010080:Oxazoles / Q000737:chemistry / Q000494:pharmacology; D054852:Small Molecule Libraries; D018874:Spheroids, Cellular / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D014746:Vimentin / Q000235:genetics / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D001688:Biological Products; D047630:Depsipeptides; D007093:Imidazoles; D010080:Oxazoles; D054852:Small Molecule Libraries; D014746:Vimentin