Both neurotoxin II from venom of Naja naja oxiana and its endogeneous analogue induce apoptosis in tumor cells

Abstract
Both neurotoxin II (NT II from venom of Naja naja oxiana) and 20–30 kDa proteins partially purified from pig brain (NTlm) cross‐reacting with antibodies to NT II were cytotoxic for L929 and K562 tumor cells at concentrations of 10−6–10−8 M. Modification of Cys residues significantly reduced cytotoxicity of NT II. Both NT2 and NTlm induced apoptosis in L929 and K562 cells.