Effect of MAPK signal transduction pathway on apoptosis of leukemia K562 cells induced by ginseng polysaccharide Effect of berbamine on apoptosis in human pulmonary carcinoma cell A549 and its mechanism 27-O-(E)-p-coumaric acyl ursolic acid via JNK/SAPK signal pathway regulates apoptosis of human breast cancer MDA-MB-231 cell line