HDACi enhance the NPC generation of hiPSCs. (A-C) Neurospheres were formed from the N-iPSC-1 cell line after HDACi treatment and the diameters of the neurospheres were measured and quantified on day 18. The error bars indicate SEM, ***P <0.001; n >/=50. Black arrows represent typical neurospheres and red arrowheads represent cell debris. (D) Acetylation levels of histone H3K9 in N-iPSC-1 cells were detected by immunostaining on day 7 of differentiation. (E, F) Neuroectodermal cells were visualized by immunostaining with antibodies against PAX6 (green) and SOX2 (red) (E) or NESTIN (green) and SOX2 (red) (F) on day 7 of differentiation. Scale bars, 50 μm. HDACi, HDAC inhibitors; hiPSCs, human induced pluripotent stem cells; SEM, standard error of the mean.