title: Glioma cells on the run - the migratory transcriptome of 10 human glioma cell lines.
abstract: BACKGROUND
  Glioblastoma multiforme (GBM) is the most common primary intracranial tumor and despite recent advances in treatment regimens, prognosis for affected patients remains poor. Active cell migration and invasion of GBM cells ultimately lead to ubiquitous tumor recurrence and patient death. To further understand the genetic mechanisms underlying the ability of glioma cells to migrate, we compared the matched transcriptional profiles of migratory and stationary populations of human glioma cells. Using a monolayer radial migration assay, motile and stationary cell populations from seven human long term glioma cell lines and three primary GBM cultures were isolated and prepared for expression analysis.
  
  
  RESULTS
  Gene expression signatures of stationary and migratory populations across all cell lines were identified using a pattern recognition approach that integrates a priori knowledge with expression data. Principal component analysis (PCA) revealed two discriminating patterns between migrating and stationary glioma cells: i) global down-regulation and ii) global up-regulation profiles that were used in a proband-based rule function implemented in GABRIEL to find subsets of genes having similar expression patterns. Genes with up-regulation pattern in migrating glioma cells were found to be overexpressed in 75% of human GBM biopsy specimens compared to normal brain. A 22 gene signature capable of classifying glioma cultures based on their migration rate was developed. Fidelity of this discovery algorithm was assessed by validation of the invasion candidate gene, connective tissue growth factor (CTGF). siRNA mediated knockdown yielded reduced in vitro migration and ex vivo invasion; immunohistochemistry on glioma invasion tissue microarray confirmed up-regulation of CTGF in invasive glioma cells.
  
  
  CONCLUSIONS
  Gene expression profiling of migratory glioma cells induced to disperse in vitro affords discovery of genomic signatures; selected candidates were validated clinically at the transcriptional and translational levels as well as through functional assays thereby underscoring the fidelity of the discovery algorithm.
authors.affiliation: Translational Genomics Research Institute, Phoenix, AZ 85004, USA. tim.demuth@gmail.com
authors.forename: Tim
authors.initials: T
authors.lastname: Demuth
authors.forename: Jessica L
authors.initials: JL
authors.lastname: Rennert
authors.forename: Dominique B
authors.initials: DB
authors.lastname: Hoelzinger
authors.forename: Linsey B
authors.initials: LB
authors.lastname: Reavie
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Nakada
authors.forename: Christian
authors.initials: C
authors.lastname: Beaudry
authors.forename: Satoko
authors.initials: S
authors.lastname: Nakada
authors.forename: Eric M
authors.initials: EM
authors.lastname: Anderson
authors.forename: Amanda N
authors.initials: AN
authors.lastname: Henrichs
authors.forename: Wendy S
authors.initials: WS
authors.lastname: McDonough
authors.forename: David
authors.initials: D
authors.lastname: Holz
authors.forename: Anna
authors.initials: A
authors.lastname: Joy
authors.forename: Richard
authors.initials: R
authors.lastname: Lin
authors.forename: Kuang H
authors.initials: KH
authors.lastname: Pan
authors.forename: Chih J
authors.initials: CJ
authors.lastname: Lih
authors.forename: Stan N
authors.initials: SN
authors.lastname: Cohen
authors.forename: Michael E
authors.initials: ME
authors.lastname: Berens
mesh_terms: D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics*; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D005910:Glioma / Q000235:genetics* / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008954:Models, Biological; D020411:Oligonucleotide Array Sequence Analysis; D025341:Principal Component Analysis; D015203:Reproducibility of Results; D015996:Survival Rate