Epidemiologic evidence in humans suggests a role for
selenium in reducing cancer incidence and mortality.
The aim of the present study was that to assess the
ability of selenium dioxide (SeO2) to enhance the
lymphocyte progression through the cell cycle in
patients with advanced (stage IV) cancer. Ten patients
(mean age 51.9 years, range: 32-74; M/F ratio: 3/7) with
tumors at different sites were included in the study. The
addition into culture of SeO2 1.5 μM enhanced
significantly the progression into S phase of PBMCs
isolated from cancer patients, whilst no significant effect
was observed on PBMCs isolated from controls. ROS
levels were significantly higher, whereas GPx activity
was significantly lower in cancer patients than controls.
Serum levels of IL-6 and TNFα were significantly higher
in cancer patients than controls. Our results show the
ability of selenium to induce a progression of PBMCs
from cancer patients into the cell cycle, which is an
essential prerequisite for the physiological functioning
of the immune system and thus positively influence the
immune status of advanced cancer patients. The
mechanism of action of selenium could be to
downregulate the production and release of
proinflammatory cytokines, which have a role in cancer
progression and particularly in the onset of cachexia