title: Genome-wide functional genetic screen with the anticancer agent AMPI-109 identifies PRL-3 as an oncogenic driver in triple-negative breast cancers.
abstract: Triple-negative breast cancers (TNBC) are among the most aggressive and heterogeneous cancers with a high propensity to invade, metastasize and relapse. Here, we demonstrate that the anticancer compound, AMPI-109, is selectively efficacious in inhibiting proliferation and inducing apoptosis of multiple TNBC subtype cell lines as assessed by activation of pro-apoptotic caspases-3 and 7, PARP cleavage and nucleosomal DNA fragmentation. AMPI-109 had little to no effect on growth in the majority of non-TNBC cell lines examined. We therefore utilized AMPI-109 in a genome-wide shRNA screen in the TNBC cell line, BT-20, to investigate the utility of AMPI-109 as a tool in helping to identify molecular alterations unique to TNBC. Our screen identified the oncogenic phosphatase, PRL-3, as a potentially important driver of TNBC growth, migration and invasion. Through stable lentiviral knock downs and transfection with catalytically impaired PRL-3 in TNBC cells, loss of PRL-3 expression, or functionality, led to substantial growth inhibition. Moreover, AMPI-109 treatment, downregulation of PRL-3 expression or impairment of PRL-3 activity reduced TNBC cell migration and invasion. Histological evaluation of human breast cancers revealed PRL-3 was significantly, though not exclusively, associated with the TNBC subtype and correlated positively with regional and distant metastases, as well as 1 and 3 year relapse free survival. Collectively, our study is proof-of-concept that AMPI-109, a selectively active agent against TNBC cell lines, can be used as a molecular tool to uncover unique drivers of disease progression, such as PRL-3, which we show promotes oncogenic phenotypes in TNBC cells.
authors.affiliation: Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Hamid H
authors.initials: HH
authors.lastname: Gari
authors.affiliation: Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Christy M
authors.initials: CM
authors.lastname: Gearheart
authors.affiliation: Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Fosmire
authors.affiliation: Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Gregory D
authors.initials: GD
authors.lastname: DeGala
authors.affiliation: Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Zeying
authors.initials: Z
authors.lastname: Fan
authors.affiliation: Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Kathleen C
authors.initials: KC
authors.lastname: Torkko
authors.affiliation: Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Edgerton
authors.affiliation: Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: M Scott
authors.initials: MS
authors.lastname: Lucia
authors.affiliation: Department of Medicine, Boston University School of Medicine, Boston, MA, USA.
authors.forename: Rahul
authors.initials: R
authors.lastname: Ray
authors.affiliation: Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Ann D
authors.initials: AD
authors.lastname: Thor
authors.affiliation: Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Porter
authors.affiliation: Department of Pathology, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Lambert
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002117:Calcitriol / Q000031:analogs & derivatives* / Q000494:pharmacology; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor / Q000379:methods; D005260:Female; D006801:Humans; D009363:Neoplasm Proteins / Q000235:genetics*; D009857:Oncogenes; D017027:Protein Tyrosine Phosphatases / Q000235:genetics*; D064726:Triple Negative Breast Neoplasms / Q000235:genetics; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: C104313:1,25-dihydroxyvitamin D3-3-bromoacetate; D000970:Antineoplastic Agents; D009363:Neoplasm Proteins; D014807:Vitamin D; C484730:PTP4A3 protein, human; D017027:Protein Tyrosine Phosphatases; D002117:Calcitriol
keywords: AMPI-109; PRL-3; functional genomics; phosphatase; triple-negative breast cancer