A mHsp70-positive tumor phenotype exerts dual functions, on the one hand, a high mHsp70 density is associated with a high aggressiveness of the tumor (16) and the potential of metastatic spread; on the other hand, mHsp70 on tumor cells serves as a target for activated natural killer (NK) cells, which have been incubated either with Hsp70 protein or TKD a 14mer peptide derived from Hsp70 in combination with low-dose IL-2 (TKD/IL-2) (12, 17, 18). This evidence concerns the gene HSPA1A and neoplasm.