LYN and acute lymphoblastic leukemia: Moreover, calpain inhibition (calpain inhibitor II or CPI-2) also induces apoptosis among acute lymphoid leukemia (ALL) and non-Hodgkin’s lymphoma B cells, which is dependent on caspase activation but not on the protein tyrosine kinases LYN or Bruton’s tyrosine kinase (BTK) [315].