title: Stabilin-1 expression in tumor associated macrophages.
abstract: Glioblastoma multiforme is a very aggressive and common form of brain tumor. Current therapies consist of a combination of surgical removal, chemotherapy and radiation therapy. These drastic treatments still leave a current prognosis of median survival of less than 1 year. Lack of effectiveness of these treatments has left researchers looking for alternative forms of treatment. A significant alternative currently being investigated is the use of the immune system to potentially target and eliminate tumor cells directly. Stabilin-1, a scavenger receptor expressed by macrophages, has the potential in inhibiting tumor growth by binding and internalizing secreted protein acidic and rich in cysteine (SPARC). SPARC is known to be upregulated in the tumor microenvironment and is involved in extracellular matrix remodeling, cell proliferation and migration. Decreasing SPARC expression using siRNA has been shown to decrease tumor invasiveness and survival. We investigated the phenotype of stabilin-1 expressing immune cells in the tumor environment and demonstrated a transient population of alternatively activated macrophages expressing stabilin-1 in the tumor environment and the disappearance of that population as the tumor progresses.
authors.affiliation: School of Medicine, Division of Biomedical Sciences, University of California, Riverside, CA 92521, USA.
authors.forename: Clément
authors.initials: C
authors.lastname: David
authors.forename: J Philip
authors.initials: JP
authors.lastname: Nance
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Hubbard
authors.forename: Mike
authors.initials: M
authors.lastname: Hsu
authors.forename: Devin
authors.initials: D
authors.lastname: Binder
authors.forename: Emma H
authors.initials: EH
authors.lastname: Wilson
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D019013:CD40 Antigens / Q000235:genetics; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D045744:Cell Line, Tumor; D018450:Disease Progression; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000276:immunology; D005909:Glioblastoma / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D006023:Glycoproteins / Q000235:genetics / Q000276:immunology; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D015676:Osteonectin; D034741:RNA, Small Interfering / Q000235:genetics; D059016:Tumor Microenvironment / Q000276:immunology*; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000276:immunology; D015854:Up-Regulation / Q000276:immunology
chemical_list: D019013:CD40 Antigens; D015816:Cell Adhesion Molecules, Neuronal; D006023:Glycoproteins; D015676:Osteonectin; D034741:RNA, Small Interfering; C578250:SPARC protein, mouse; C486732:Stab1 protein, mouse; D025521:Tumor Suppressor Proteins