WASHINGTONUmbilical cord blood cells alone have no cytotoxic
properties, but studies show that when activated with interleukin-2 (IL-2),
they may have some therapeutic effects against breast cancer, said Shantaram S.
Joshi, PhD, associate professor of cell biology and anatomy, University of
Nebraska Medical Center.
Studies in Three Cell Lines
Dr. Joshi, who spoke at the Susan G. Komen Breast Cancer
Foundation annual scientific conference, used three cell linesT47D, MCF-7,
and MDA-231in his tests of cytokine-activated mononuclear cells from human
umbilical cord blood.
Without activation, the cord blood mononuclear cells showed no
antitumor activity. But following in vitro activation with IL-2, cord blood
mononuclear cells demonstrated significantly increased cytotoxicity against
human breast cancer in vitro as well as in vivo against MDA-231 human breast
cancer cells grown in SCID mice.
Adding granulocyte macrophage-colony stimulating factor
(GM-CSF) and macrophage-colony stimulating factor (M-CSF) to IL-2 increased
activation of cytotoxic effector cells and cytotoxicity of cord blood cells
against human breast cancer cells, Dr. Joshi said. GM-CSF or M-CSF combined
with IL-2 significantly increased the natural-killer cell and dendritic cell
population in mononuclear cells derived from cord blood.
"These studies suggest that combination of IL-2 with
GM-CSF or M-CSF might be useful in inhibiting the growth of breast cancer in
vivo," Dr. Joshi said, "and may lay the foundation for exploring the
use of cord blood cells for therapy against breast cancer."