To further determine whether c-myb is involved in Vav1 expression, we analyzed its expression in cells of different histological origins and found that c-myb mRNA and protein is present in Jurkat T cells and at lower levels in H441 lung cancer cells, but is hardly detectable in H460 lung cancer cells that do not express vav1 (Fig. 5A). This evidence concerns the gene VAV1 and lung carcinoma.