Fig. 4.

Switching JHH-NF1-PA1 cultures to FBS condition induced apoptosis, senescence and inhibited cell proliferation. (A, B) Slow growth of JHH-NF1-PA1 cells switched to FBS conditions. (C) After 7 days in FBS conditions, JHH-NF1-PA1 cells accumulated in G1 phase. (D, E) Decreased proliferation (BrdU+ cells) and increased apoptosis (Annexin V assay) after the switch to FBS conditions. (F, G) Levels of p27 protein and mRNA also increased when JHH-NF1-PA1 was cultured in FBS. (H) Induction of acidic β-galactosidase-positive cells in FBS (*P < .05, **P < .01). BrdU, bromodeoxyuridine; FBS, fetal bovine serum; PA, pilocytic astrocytoma.