title: In vitro age-related responses of endothelial cells to breast cancer cell addition.
abstract: OBJECTIVE
  The purpose of this study was to determine if the in vitro age of endothelial cells alters endothelial response(s) to breast cancer cells.
  
  
  METHODS
  After characterizing lower passage ("young"; passages 10-16) and higher passage ("old"; passages 30-36) bovine pulmonary artery endothelial cells (BPAECs), fluorescently labeled MCF-7 breast cancer cells were added to confluent monolayers of young and old BPAECs.
  
  
  RESULTS
  Transient gaps that peaked in size by 12 h and closed by 48h occurred between the young BPAECs, while large persistent gaps formed between the old BPAECs. Gap formation did not occur when 184A1 cells, a non-malignant mammary epithelial cell line, were added in place of MCF-7 cells, suggesting that the age-related responses of the endothelial cells to MCF-7 cell addition were specific to the tumor cell addition. Additionally, more MCF-7 cells migrated through old BPAEC monolayers, than young BPAEC monolayers, grown on Matrigel-coated filters. Finally, DNA fragmentation and fluorescent annexin-V binding assays suggested increased MCF-7 cell-induced apoptosis in older BPAECs, though results from a caspase-3 activation assay were equivocal.
  
  
  CONCLUSIONS
  In sum, our findings support the notion that aged endothelial cells are more susceptible to breast cancer-induced injury, perhaps due to increased apoptosis.
authors.affiliation: College of Nursing, The University of Arizona, Tucson, AZ 85721, USA. cmerkle@nursing.arizona.edu
authors.forename: Carrie J
authors.initials: CJ
authors.lastname: Merkle
authors.forename: Bonny J
authors.initials: BJ
authors.lastname: Torres
authors.forename: Jean M
authors.initials: JM
authors.lastname: Baruch
authors.forename: Katherine
authors.initials: K
authors.lastname: Stevens
authors.forename: Christine
authors.initials: C
authors.lastname: Munoz
authors.forename: Richard C
authors.initials: RC
authors.lastname: Schaeffer
authors.forename: David W
authors.initials: DW
authors.lastname: Montgomery
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001943:Breast Neoplasms / Q000378:metabolism*; D002417:Cattle; D002450:Cell Communication / Q000502:physiology*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology; D016922:Cellular Senescence / Q000502:physiology*; D018920:Coculture Techniques; D042783:Endothelial Cells / Q000166:cytology* / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted