Conversely, in Wee1-siRNAs or Cdk1-AF-overepressing cells the overall amount of Kif18A on spindles was lower than control cells and in particular it failed to concentrate at the spindle center and at the plus ends of K-MT, rather remaining around the spindle pole area (Figures 2A, B). This evidence concerns the gene WEE1 and atrial fibrillation.