title: Identification of a pharmacologically tractable Fra-1/ADORA2B axis promoting breast cancer metastasis.
abstract: Metastasis confronts clinicians with two major challenges: estimating the patient's risk of metastasis and identifying therapeutic targets. Because they are key signal integrators connecting cellular processes to clinical outcome, we aimed to identify transcriptional nodes regulating cancer cell metastasis. Using rodent xenograft models that we previously developed, we identified the transcription factor Fos-related antigen-1 (Fra-1) as a key coordinator of metastasis. Because Fra-1 often is overexpressed in human metastatic breast cancers and has been shown to control their invasive potential in vitro, we aimed to assess the implication and prognostic significance of the Fra-1-dependent genetic program in breast cancer metastasis and to identify potential Fra-1-dependent therapeutic targets. In several in vivo assays in mice, we demonstrate that stable RNAi depletion of Fra-1 from human breast cancer cells strongly suppresses their ability to metastasize. These results support a clinically important role for Fra-1 and the genetic program it controls. We show that a Fra-1-dependent gene-expression signature accurately predicts recurrence of breast cancer. Furthermore, a synthetic lethal drug screen revealed that antagonists of the adenosine receptor A2B (ADORA2B) are preferentially toxic to breast tumor cells expressing Fra-1. Both RNAi silencing and pharmacologic blockade of ADORA2B inhibited filopodia formation and invasive activity of breast cancer cells and correspondingly reduced tumor outgrowth in the lungs. These data show that Fra-1 activity is causally involved in and is a prognostic indicator of breast cancer metastasis. They suggest that Fra-1 activity predicts responsiveness to inhibition of pharmacologically tractable targets, such as ADORA2B, which may be used for clinical interference of metastatic breast cancer.
authors.affiliation: Department of Molecular Oncology, The Netherlands Cancer Institute, 1066 CX, Amsterdam, The Netherlands.
authors.forename: Christophe J
authors.initials: CJ
authors.lastname: Desmet
authors.forename: Tristan
authors.initials: T
authors.lastname: Gallenne
authors.forename: Alexandre
authors.initials: A
authors.lastname: Prieur
authors.forename: Fabien
authors.initials: F
authors.lastname: Reyal
authors.forename: Nils L
authors.initials: NL
authors.lastname: Visser
authors.forename: Ben S
authors.initials: BS
authors.lastname: Wittner
authors.forename: Marjon A
authors.initials: MA
authors.lastname: Smit
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Geiger
authors.forename: Jamila
authors.initials: J
authors.lastname: Laoukili
authors.forename: Sedef
authors.initials: S
authors.lastname: Iskit
authors.forename: Boris
authors.initials: B
authors.lastname: Rodenko
authors.forename: Wilbert
authors.initials: W
authors.lastname: Zwart
authors.forename: Bastiaan
authors.initials: B
authors.lastname: Evers
authors.forename: Hugo
authors.initials: H
authors.lastname: Horlings
authors.forename: Abderrahrim
authors.initials: A
authors.lastname: Ajouaou
authors.forename: John
authors.initials: J
authors.lastname: Zevenhoven
authors.forename: Martin
authors.initials: M
authors.lastname: van Vliet
authors.forename: Sridhar
authors.initials: S
authors.lastname: Ramaswamy
authors.forename: Lodewyk F A
authors.initials: LF
authors.lastname: Wessels
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Peeper
mesh_terms: D058917:Adenosine A2 Receptor Antagonists / Q000494:pharmacology; D000818:Animals; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism*; D011554:Pseudopodia / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D051381:Rats; D043704:Receptor, Adenosine A2B / Q000235:genetics / Q000378:metabolism*; D014183:Transplantation, Heterologous; D023041:Xenograft Model Antitumor Assays; D000099169:Fos-Related Antigen 1
chemical_list: D058917:Adenosine A2 Receptor Antagonists; D016760:Proto-Oncogene Proteins c-fos; D043704:Receptor, Adenosine A2B; D000099169:Fos-Related Antigen 1