title: Effect of SP600125 on the mitotic spindle in HeLa Cells, leading to mitotic arrest, endoreduplication and apoptosis.
abstract: BACKGROUND
  The JNK inhibitor SP600125 strongly inhibits cell proliferation in many human cancer cells by blocking mitosis progression and inducing cell death. Despite, all this study, the mechanism by which SP600125 inhibits mitosis-related effects in human cervical cells (HeLa cells) remains unclear. In this study, we investigated the effects of SP600125 on the cell viability, cell cycle, and on the spindle assembly during mitosis in HeLa cells.
  
  
  METHODS
  To explore this approach, we used a viability test, an immunofluorescence microscopy to detect Histone phosphorylation and mitotic spindle aberrations. Apoptosis was characterised using Western Blotting.
  
  
  RESULTS
  Treatment of HeLa cells with varying concentrations of SP600125 induces significant G2/M cell cycle arrest with elevated phosphorylation of histone H3 within 48 h, and endoreduplication after 48 h. SP600125 also induces significant abnormal mitotic spindle. High concentrations of SP600125 (20 μM) induce disturbing microtubule assembly in vitro. Additionally, SP600125- induced delayed apoptosis and cell death was accompanied by significant poly ADP-ribose polymerase (PARP) cleavage and caspase-3 activation in the late phase (at 72 h).
  
  
  CONCLUSIONS
  Our results confirmed that SP600125 induce mitosis arrest in G2/M, endoreduplication, mitotic spindle aberrations and apoptosis.
authors.affiliation: UR 12ES08 "Signalisation Cellulaire et Pathologies" Faculté de Médecine Monastir, Université de Monastir, Monastir, Tunisie.
authors.forename: Donia
authors.initials: D
authors.lastname: Mili
authors.affiliation: UR 12ES08 "Signalisation Cellulaire et Pathologies" Faculté de Médecine Monastir, Université de Monastir, Monastir, Tunisie.
authors.forename: Kaouthar
authors.initials: K
authors.lastname: Abid
authors.affiliation: UR 12ES08 "Signalisation Cellulaire et Pathologies" Faculté de Médecine Monastir, Université de Monastir, Monastir, Tunisie.
authors.forename: Imed
authors.initials: I
authors.lastname: Rjiba
authors.affiliation: UR 12ES08 "Signalisation Cellulaire et Pathologies" Faculté de Médecine Monastir, Université de Monastir, Monastir, Tunisie.
authors.forename: Abderraouf
authors.initials: A
authors.lastname: Kenani
keywords: Apoptosis; HeLa cells; Mitotic spindle; SP600125