Figure 4. Acetyl-cinobufagin induced S/G2 cell cycle arrest. (A) Cell cycle distribution in MDA-MB-468 and BT-549 cells treated with acetyl-cinobufagin treatment evaluated by flow cytometry. (B, C) The immunoblotting analysis was performed to determine the levels of cyclin A1 and CDK2 after treatment with acetyl-cinobufagin. *p < 0.05; **p < 0.01; ***p < 0.001 compared with the control based on Student’s t-test.