GZMB and neoplasm: It is assumed that a 14-mer sequence, the so-called TKD motif (TKDNNLLGRFELSG; amino acids 450–463) of the C-terminal domain of human Hsp70 (hHsp70), facilitates activation of NK cells, recruitment and uptake of GrB into tumour cells habouring Hsp70 on their cell surface (Sutton et al. 2003; Gross et al. 2003).