In breast cancer, kaempferol arrests the cell cycle in the G2/M phase by decreasing the level of cyclin-dependent kinase 1 (CDK1) (55) and inhibiting migration and invasion by blocking the PKCδ (protein kinase C)/mitogen-activated protein kinase (MAPK)/activator protein 1 (AP-1) cascade and the expression of MMP-9 (matrix metalloproteinases) (56). The gene discussed is CDK1; the disease is breast cancer.