title: ROCK Inhibition Facilitates In Vitro Expansion of Glioblastoma Stem-Like Cells.
abstract: Due to their stem-like characteristics and their resistance to existing chemo- and radiation therapies, there is a growing appreciation that cancer stem cells (CSCs) are the root cause behind cancer metastasis and recurrence. However, these cells represent a small subpopulation of cancer cells and are difficult to propagate in vitro. Glioblastoma is an extremely deadly form of brain cancer that is hypothesized to have a subpopulation of CSCs called glioblastoma stem cells (GSCs; also called brain tumor initiating cells, BTICs). We propose the use of selective Rho-kinase (ROCK) inhibitors, Y-27632 and fasudil, to promote GSC/BTIC-like cell survival and propagation in vitro. ROCK inhibitors have been implicated in suppressing apoptosis, and it was hypothesized that they would increase the number of GSC/BTIC-like cells grown in vitro and improve cloning efficiencies. Indeed, our data demonstrate that transient and continuous supplementation of non-toxic concentrations of Y-27632 and fasudil inhibited apoptosis, enhanced the cells' ability to form spheres, and increased stem cell marker expressing GSC/BTIC-like cell subpopulation. Our data indicated that pharmacological and genetic (siRNA) inhibitions of the ROCK pathway facilitates in vitro expansion of GSC/BTIC-like cells. Thus, ROCK pathway inhibition shows promise for future optimization of CSC culture media.
authors.affiliation: Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama, United States of America.
authors.forename: Samantha G
authors.initials: SG
authors.lastname: Tilson
authors.affiliation: Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama, United States of America.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Haley
authors.affiliation: Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama, United States of America.
authors.forename: Ursula L
authors.initials: UL
authors.lastname: Triantafillu
authors.affiliation: Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama, United States of America.
authors.forename: David A
authors.initials: DA
authors.lastname: Dozier
authors.affiliation: Department of Neurosurgery, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America.
authors.forename: Catherine P
authors.initials: CP
authors.lastname: Langford
authors.affiliation: Department of Neurosurgery, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America.
authors.forename: G Yancey
authors.initials: GY
authors.lastname: Gillespie
authors.affiliation: Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama, United States of America.
authors.forename: Yonghyun
authors.initials: Y
authors.lastname: Kim
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001932:Brain Neoplasms / Q000473:pathology*; D045744:Cell Line, Tumor; D005909:Glioblastoma / Q000473:pathology*; D006801:Humans; D066298:In Vitro Techniques; D014411:Neoplastic Stem Cells / Q000473:pathology*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors*
chemical_list: D047428:Protein Kinase Inhibitors; D054460:rho-Associated Kinases