Functionally, coculturing T-ALL cells with meningeal stromal cells resulted in increased expression of VLA-4 on KOPTK1 and PER117 cells (Figure 7F) concomitant with elevated levels of VCAM-1 in LeC, Per, and DuF (Figure 7, G–I). This evidence concerns the gene VCAM1 and acute lymphoblastic leukemia.