title: Polysialic acid facilitates tumor invasion by glioma cells.
abstract: Polysialic acid (PSA) is thought to attenuate neural cell adhesion molecule (NCAM) adhesion, thereby facilitating neural cell migration and regeneration. Although the expression of PSA has been shown to correlate with the progression of certain tumors such as small cell lung carcinoma, there have been no studies to determine the roles of PSA in gliomas, the most common type of primary brain tumor in humans. In this study, we first revealed that among patients with glioma, PSA was detected more frequently in diffuse astrocytoma cells, which spread extensively. To determine directly the role of PSA in glioma cell invasion, we transfected C6 glioma cells with polysialyltransferases to express PSA. In those transfected cells, PSA is attached mainly to NCAM-140, whereas the mock-transfected C6 cells express equivalent amounts of PSA-free NCAM-140. Both PSA negative and positive C6 cell lines exhibited almost identical growth rates measured in vitro. However, PSA positive C6 cells exhibited increased invasion to the corpus callosum, where the mock-transfected C6 glioma cells rarely invaded when inoculated into the brain. By contrast, the invasion to the corpus callosum by both the mock-transfected and PSA positive C6 cells was observed in NCAM-deficient mice. These results combined indicate that PSA facilitates tumor invasion of glioma in the brain, and that NCAM-NCAM interaction is likely attenuated in the PSA-mediated tumor invasion.
authors.affiliation: Glycobiology, Cancer Research Center, The Burnham Institute, La Jolla, CA 92037, USA.
authors.forename: Masami
authors.initials: M
authors.lastname: Suzuki
authors.forename: Misa
authors.initials: M
authors.lastname: Suzuki
authors.forename: Jun
authors.initials: J
authors.lastname: Nakayama
authors.forename: Atsushi
authors.initials: A
authors.lastname: Suzuki
authors.forename: Kiyohiko
authors.initials: K
authors.lastname: Angata
authors.forename: Shihao
authors.initials: S
authors.lastname: Chen
authors.forename: Keiichi
authors.initials: K
authors.lastname: Sakai
authors.forename: Kazuki
authors.initials: K
authors.lastname: Hagihara
authors.forename: Yu
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: Minoru
authors.initials: M
authors.lastname: Fukuda
mesh_terms: D001254:Astrocytoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D002448:Cell Adhesion / Q000235:genetics; D045744:Cell Line, Tumor; D002551:Cerebral Ventricle Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D003337:Corpus Callosum / Q000378:metabolism / Q000473:pathology; D006801:Humans; D009361:Neoplasm Invasiveness; D019006:Neural Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D012794:Sialic Acids / Q000378:metabolism*
chemical_list: D019006:Neural Cell Adhesion Molecules; D012794:Sialic Acids; C021319:polysialic acid