title: Amorphous silica nanoparticles alter microtubule dynamics and cell migration.
abstract: Amorphous silica nanoparticles (SiO2-NPs) have been studied for their toxic and genotoxic potential. Although contradictory data have been reported and the possible modes of action are not fully elucidated, aneugenic events have been reported, indicating the microtubule (MT) network as a potential target. To investigate this, we examined the effects of 59 nm (10 µg/ml) and 174 nm (7.5 µg/ml) SiO2-NPs on MTs in mitotic and interphase A549 human lung carcinoma cells. No gross morphological changes of the mitotic spindle or induction of multipolar spindles were observed upon SiO2-NPs treatment. The influence of SiO2-NPs on the interphase MTs network dynamics was investigated by in situ depolymerisation/repolymerisation experiments. Results showed a clear increase in MT dynamics after SiO2-NP treatment. Consistent with this, reduced levels of MT acetylation were observed. In addition, live cell microscopy demonstrated that SiO2-NP treatment reduced A549 cell motility. The SiO2-NP doses and conditions (serum-free) used in this study did not induce significant cell toxicity or MN frequencies. Therefore, the effects on MT dynamics, MT acetylation and migration observed, are direct effects of the SiO2-NPs and not a consequence of NP overload or toxic or genotoxic effects.
authors.affiliation: Laboratory of Cell Genetics, Vrije Universiteit Brussel , Brussels , Belgium .
authors.forename: Laetitia
authors.initials: L
authors.lastname: Gonzalez
authors.forename: Marco
authors.initials: M
authors.lastname: De Santis Puzzonia
authors.forename: Raffaele
authors.initials: R
authors.lastname: Ricci
authors.forename: Federica
authors.initials: F
authors.lastname: Aureli
authors.forename: Giulia
authors.initials: G
authors.lastname: Guarguaglini
authors.forename: Francesco
authors.initials: F
authors.lastname: Cubadda
authors.forename: Luc
authors.initials: L
authors.lastname: Leyns
authors.forename: Enrico
authors.initials: E
authors.lastname: Cundari
authors.forename: Micheline
authors.initials: M
authors.lastname: Kirsch-Volders
mesh_terms: D000107:Acetylation; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects*; D006801:Humans; D008856:Microscopy, Fluorescence; D018715:Microscopy, Video; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D008938:Mitosis / Q000187:drug effects*; D053758:Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D010316:Particle Size; D012822:Silicon Dioxide / Q000737:chemistry / Q000633:toxicity*; D008941:Spindle Apparatus / Q000378:metabolism; D013499:Surface Properties
chemical_list: D008869:Microtubule-Associated Proteins; D012822:Silicon Dioxide
keywords: Cell migration; in vitro; microtubule dynamics; mode of action; silica nanoparticles