We hypothesized that NTSR2 stimulation depended on activation of autocrine and/or paracrine loops following release of NTS, as we showed previously for NTSR1 in normal B lymphocytes.14 To investigate the role of NTS in modulating apoptosis, we monitored its effect on expression in B lymphocytes derived from B-CLL patients. This evidence concerns the gene NTSR2 and B-cell chronic lymphocytic leukemia.