Sinomenine hydrochloride (SH) selectively kills human glioblastoma cells, but not normal glial cells, and induces human glioblastoma cell cycle arrest. (A) The human glioblastoma cell lines were treated with SH (0.0625 to 1.0 mM) for 24 h, and cell counting kit-8 (CCK-8) assays were applied to analyze cell viability; (B) HA-h cells were treated with SH (0.0625 to 1.0 mM) for the indicated time points, and CCK-8 assays were used to examine cell viability; (C) Analysis of the DNA content and histograms of the cell cycle phase distribution of U87 and SF767 cells treated with SH (0.25, 0.5 mM) for 24 h; (D) The indicated concentrations of SH dose-dependently altered the levels of cell cycle-related proteins in U87 and SF767 cells at 24 h. Each blot and image shown is representative of n = 3 experiments. All data are presented as means ± SEM, n = 3. * p < 0.05, ** p < 0.01 compared with the control.