Tumors of the nervous system, including
neuroblastoma and
glioblastoma, are difficult to treat with current
therapies. Despite the advances in
cancer therapeutics, the outcomes in these patients remain poor and, therefore, new modalities are required. Recent literature demonstrates that cytotoxic effector cells can effectively kill
tumors of the nervous system. In addition, we have previously shown that umbilical cord blood (UCB) contains precursors of antitumor cytotoxic effector cells. Therefore, to evaluate the antitumor potential of UCB-derived effector cells, studies were designed to compare the in vitro and in vivo antitumor effects of UCB- and peripheral blood (PB)-derived
antigen-nonspecific and
antigen-specific effector cells against
tumors of the nervous system. Mononuclear cells (MNCs) from UCB were used to generate both
interleukin-2 (IL-2)-activated killer (LAK) cells and
tumor-specific cytotoxic T lymphocytes (CTLs). UCB-derived LAK cells showed a significant in vitro cytotoxicity against IMR-32, SK-NMC, and U-87 human
neuroblastoma and
glioblastoma, respectively. In addition, the CTLs generated using dendritic cells primed with IMR-32
tumor cell lysate showed a selective cytotoxicity in vitro against IMR-32 cells, but not against U-87 or MDA-231 cells. Furthermore, treatment of SCID mice bearing IMR-32
neuroblastoma with
tumor-specific CTLs resulted in a significant (p < 0.01) inhibition of
tumor growth and increased overall survival. Thus, these results demonstrate the potential of UCB-derived effector cells against human
neuroblastoma and warrant further preclinical studies.