Figure 4.

PSH-induced cell cycle arrest is ARA1-dependent. (A) The protein expression levels of ARA1 were measured by western blotting. (B) U251 cells were treated with 20 nM CCPA and 100 µg/ml PSH for 48 h, and the protein expression levels of ARA1, P27 and cyclin D were measured by western blotting. (C) The cell cycle was analyzed by flow cytometry using PI staining. Experiments were repeated three times, and the data are presented as the mean ± SD. ^**P<0.01 vs. control; ^&&P<0.01 vs. PSH. PSH, Paris saponin H; ARA1, A1 adenosine receptor; CCPA, 2-chloro-N6-cyclopentyladenosine.