title: Modeling and characterization of inflammatory breast cancer emboli grown in vitro.
abstract: Inflammatory breast cancer (IBC) is the deadliest form of breast cancer, presenting as intralymphatic emboli. Emboli within the dermal lymphatic vessels are thought to contribute to rapid metastasis. The lack of appropriate in vitro models has made it difficult to accurately study how IBC emboli metastasize. To date, attempts at creating IBC tumor emboli in vitro have used 3D culture on a solid layer of Matrigel(TM) , which does not resemble the physical properties of the lymphatic system. Dermal lymphatic fluid produces oscillatory fluid shear forces and is 1.5-1.7-fold more viscous than water with a pH range of 7.5-7.7. We have established a method for forming tumor emboli by culturing the IBC cell lines in suspension with either polyethylene glycol- or hyaluronic acid-containing medium and oscillatory fluid shear forces. Non-IBC cells do not form emboli under identical conditions. In vitro IBC emboli were analyzed for expression of markers associated with patient emboli and their ability to undergo invasion. In a direct comparison, the in vitro IBC emboli closely resemble IBC patient emboli with respect to size, composition and E-cadherin expression. Further, cells from the emboli are able to invade in clusters via RhoC GTPase-dependent amoeboid movement. Invasion by clusters of IBC cells is disrupted by exposure to TGFβ. This study provides a biologically relevant in vitro model to accurately grow and study inflammatory breast cancer biology and metastasis.
authors.affiliation: Laboratory for Cytoskeletal Physiology, Department of Biological Sciences, The University of Delaware, Newark, DE 19716, USA.
authors.forename: Heather L
authors.initials: HL
authors.lastname: Lehman
authors.forename: Erica J
authors.initials: EJ
authors.lastname: Dashner
authors.forename: Michelle
authors.initials: M
authors.lastname: Lucey
authors.forename: Peter
authors.initials: P
authors.lastname: Vermeulen
authors.forename: Luc
authors.initials: L
authors.lastname: Dirix
authors.forename: Steven
authors.initials: S
authors.lastname: Van Laere
authors.forename: Kenneth L
authors.initials: KL
authors.lastname: van Golen
mesh_terms: D015153:Blotting, Western; D015820:Cadherins / Q000378:metabolism; D045744:Cell Line, Tumor; D020405:Dermis; D005260:Female; D020558:GTP Phosphohydrolases / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D058922:Inflammatory Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D042601:Lymphatic Vessels; D009361:Neoplasm Invasiveness; D009360:Neoplastic Cells, Circulating; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism; D015398:Signal Transduction; D016212:Transforming Growth Factor beta / Q000378:metabolism* / Q000494:pharmacology; D020741:rho GTP-Binding Proteins / Q000378:metabolism; D000075024:rhoC GTP-Binding Protein
chemical_list: D015820:Cadherins; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta; D020558:GTP Phosphohydrolases; C066690:RHOC protein, human; D020741:rho GTP-Binding Proteins; D000075024:rhoC GTP-Binding Protein