title: Intracellular Expression of PAI-1 Specific Aptamers Alters Breast Cancer Cell Migration, Invasion and Angiogenesis.
abstract: Plasminogen activator inhibitor-1 (PAI-1) is elevated in various cancers, where it has been shown to effect cell migration and invasion and angiogenesis. While, PAI-1 is a secreted protein, its intercellular levels are increased in cancer cells. Consequently, intracellular PAI-1 could contribute to cancer progression. While various small molecule inhibitors of PAI-1 are currently being investigated, none specifically target intracellular PAI-1. A class of inhibitors, termed aptamers, has been used effectively in several clinical applications. We previously generated RNA aptamers that target PAI-1 and demonstrated their ability to inhibit extracellular PAI-1. In the current study we explored the effect of these aptamers on intracellular PAI-1. We transiently transfected the PAI-1 specific aptamers into both MDA-MB-231 human breast cancer cells, and human umbilical vein endothelial cells (HUVECs) and studied their effects on cell migration, invasion and angiogenesis. Aptamer expressing MDA-MB-231 cells exhibited a decrease in cell migration and invasion. Additionally, intracellular PAI-1 and urokinase plasminogen activator (uPA) protein levels decreased, while the PAI-1/uPA complex increased. Moreover, a significant decrease in endothelial tube formation in HUVECs transfected with the aptamers was observed. In contrast, conditioned media from aptamer transfected MDA-MB-231 cells displayed a slight pro-angiogenic effect. Collectively, our study shows that expressing functional aptamers inside breast and endothelial cells is feasible and may exhibit therapeutic potential.
authors.affiliation: Department of Pediatric Hematology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America.|Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America.
authors.forename: Yolanda M
authors.initials: YM
authors.lastname: Fortenberry
authors.affiliation: Department of Pediatric Hematology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America.
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Brandal
authors.affiliation: Laboratoire CRRET, Faculté des Sciences et Technologie, Université Paris-Est Créteil, 61 avenue du général De Gaulle, 94010 Créteil, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Carpentier
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America.
authors.forename: Malvi
authors.initials: M
authors.lastname: Hemani
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America.
authors.forename: Arvind P
authors.initials: AP
authors.lastname: Pathak
mesh_terms: D052157:Aptamers, Nucleotide / Q000235:genetics / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology; D002448:Cell Adhesion; D045744:Cell Line, Tumor; D002465:Cell Movement; D002470:Cell Survival; D016207:Cytokines / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D018919:Neovascularization, Physiologic; D017395:Plasminogen Activator Inhibitor 1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014568:Urokinase-Type Plasminogen Activator / Q000037:antagonists & inhibitors / Q000378:metabolism; D019096:Vitronectin / Q000378:metabolism
chemical_list: D052157:Aptamers, Nucleotide; D016207:Cytokines; D017395:Plasminogen Activator Inhibitor 1; D019096:Vitronectin; D014568:Urokinase-Type Plasminogen Activator