Tumor-specific CD8+cytotoxic T lymphocytes (CTLs) are generated by repetitive stimulation of peripheral blood mononuclear cells (PBMCs) with tumor-associated antigen (TAA) expressing antigen-presenting cells (APC) such as dendritic cells (DCs) and certain cytokines including interleukin- (IL-) 2, IL-7, IL-12, IL-15, and IL-21 [3, 4]. This evidence concerns the gene IL21 and neoplasm.