For example, a discrepancy between CCR7 level of expression and CCL19 induced chemotaxis has been shown for B cells in mantle cell lymphoma [18], CCR7 expression is altered in primary central nervous system lymphoma [35], and CCL19 is also associated with resistance to apoptosis in B-cell Acute Lymphocytic Leukemia [36]. This evidence concerns the gene CCL19 and precursor B-cell acute lymphoblastic leukemia.