CD5 and B-cell chronic lymphocytic leukemia: Similarly, our early studies have also demonstrated that in B-cell acute lymphoblastic leukemia (B-ALL) and B-cell chronic lymphocytic leukemia (B-CLL), CXCL13 and CCL19 together upregulate PEG10 expression in CD23+CD5+ or CD19+CD34+ B cells and then hamper the activation of caspase-3 and caspase-8 to gain the apoptosis resistance induced by tumor necrosis factor-α (TNF-α) [46, 47].