VAV1 and lung cancer: Following transfection, luciferase was expressed at high levels in the Vav1-expressing cells (Jurkat, U937 and H441), but its expression level was very low in the vav1-negative cell lines (H460, A549 and Panc1) Luciferase expression in H441 lung cancer cells was even higher than in Jurkat T cells (Fig. 2A).