Actin dynamics are important for cell migration and at least for head and neck cancers and chronic leukemias, CCR7-activated actin filament accumulation at the cell membrane by stimulation of small GTPases, RhoA and Cdc42, leading to lamellipodia, membrane ruffling and promotion of cell migration and invasive behavior [188,189,264,265]. The gene discussed is CCR7; the disease is chronic leukemia.