MAPK8 and cancer: Cancer cells were treated with strophanthidin for 24 h, and the total cell lysates were analyzed using Phospho-MEK1/2 (Ser217/Ser221), Phospho p38 MAPK (Thr180/Tyr182), Phospho p44/42 MAPK (Thr202/Tyr204), and Phospho-SAPK/JNK (Thr183/Tyr185).