Caffeine Sensitizes U87-MG Human Glioblastoma Cells to Temozolomide through Mitotic Catastrophe by Impeding G2 Arrest

Figure 5

Immunoblotting analysis showed that TMZ-induced activation of ATM/p53/p21 pathway was repressed by concurrent caffeine (TMZ versus TC), and it was further inhibited by preexposure of caffeine 24 h ahead of combined therapy (TC versus CTC). GAPDH was used as an internal loading control. , #, and & represent for p < 0.05 when compared to control, TMZ, and TC, respectively.