title: EP4 receptor promotes invadopodia and invasion in human breast cancer.
abstract: The production of Prostaglandin E2(PGE2) is elevated in human breast cancer cells. The abnormal expression of COX-2, which is involved in the synthesis of PGE2, was recently reported as a critical determinant for invasiveness of human breast cancer cells. Autocrine and paracrine PGE2-mediated stimulation of the PGE2receptor EP4 transduces multiple signaling pathways leading to diverse patho-physiological effects, including tumor cell invasion and metastasis. It is known that PGE2-induced EP4 activation can transactivate the intracellular signaling pathway of the epidermal growth factor receptor (EGFR). In malignant cancer cells, EGFR pathway activation promotes invadopodia protrusions, which further leads to degradation of the surrounding extracellular matrix (ECM). Despite the known influence of EP4 on the EGFR signaling pathway, the effect of EP4 stimulation on invadopodia formation in human breast cancer was never tested directly. Here we demonstrate the involvement of EP4 in invasion and its effect on invadopodia in breast cancer MDA-MB-231 cells using 2D invadopodia and 3D invasion in vitro assays as well as intravital microscopy. The results show that stimulation with the selective EP4 agonist CAY10598 or PGE2promotes invadopodia-mediated degradation of the ECM, as well as the invasion of breast cancer cells in in vitro models. The effect on matrix degradation can be abrogated via direct inhibition of EP4 signaling as well as via inhibition of EGFR tyrosine kinase, indicating that EP4-mediated effects on invadopodia-driven degradation are EGFR dependent. Finally, using xenograft mouse models, we show that short-term systemic treatment with CAY10598 results in a >9-fold increase in the number of invadopodia. These findings highlight the importance of further investigation on the role of EP4-EGFR crosstalk in invadopodia formation.
authors.affiliation: Department of Cell Biology, Radboud Institute for Molecular Life Science, Radboud University Medical Center, Geert Grooteplein 28, 6525 GA, Nijmegen, The Netherlands; Department of Bioengineering, Temple University, 1947 N 12th St, 19122, Philadelphia, PA, USA.
authors.forename: Felix
authors.initials: F
authors.lastname: Tönisen
authors.affiliation: Department of Bioengineering, Temple University, 1947 N 12th St, 19122, Philadelphia, PA, USA.
authors.forename: Louisiane
authors.initials: L
authors.lastname: Perrin
authors.affiliation: Department of Bioengineering, Temple University, 1947 N 12th St, 19122, Philadelphia, PA, USA.
authors.forename: Battuya
authors.initials: B
authors.lastname: Bayarmagnai
authors.affiliation: Department of Cell Biology, Radboud Institute for Molecular Life Science, Radboud University Medical Center, Geert Grooteplein 28, 6525 GA, Nijmegen, The Netherlands.
authors.forename: Koen
authors.initials: K
authors.lastname: van den Dries
authors.affiliation: Department of Cell Biology, Radboud Institute for Molecular Life Science, Radboud University Medical Center, Geert Grooteplein 28, 6525 GA, Nijmegen, The Netherlands.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Cambi
authors.affiliation: Department of Bioengineering, Temple University, 1947 N 12th St, 19122, Philadelphia, PA, USA; Fox Chase Cancer Center, Cancer Biology Program, 7710 Burholme Ave, 19111, Philadelphia, PA, USA. Electronic address: bojana@temple.edu.
authors.forename: Bojana
authors.initials: B
authors.lastname: Gligorijevic
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000502:physiology; D015232:Dinoprostone / Q000494:pharmacology; D066246:ErbB Receptors / Q000378:metabolism; D005260:Female; D064593:Heterografts; D006801:Humans; D000069416:Intravital Microscopy / Q000379:methods; D051379:Mice; D016513:Mice, SCID; D009361:Neoplasm Invasiveness; D000069261:Podosomes / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D011760:Pyrrolidinones / Q000494:pharmacology; D058309:Receptors, Prostaglandin E, EP4 Subtype / Q000819:agonists / Q000378:metabolism*; D015398:Signal Transduction; D013777:Tetrazoles / Q000494:pharmacology; D014162:Transfection
chemical_list: C000598602:CAY10598; D011760:Pyrrolidinones; D058309:Receptors, Prostaglandin E, EP4 Subtype; D013777:Tetrazoles; C512478:EGFR protein, human; D066246:ErbB Receptors; D015232:Dinoprostone
keywords: EP4; Intravital microscopy; Invadopodia; Invasion; Prostaglandin E(2); Spheroids