Figure 1. Bufotalin inhibits cell proliferation in GBM cells. (A) The molecular structure of bufotalin. (B, C) CCK-8 assay was used to determine the cell viability of U87 and U251 cells treated with bufotalin for 24 h and 48 h. (D–G) Bufotalin suppressed U87 and U251 cells’ colony formation. The data are representative of three independent experiments and are presented as the mean ± SD. Significant differences compared with the control are indicated by *p < 0.05, **p < 0.01, and ***p < 0.001.