4. Conclusions
At present, chemotherapy is usually adopted as one of the
main measures for tumor therapy. However, the adequate dosage
in a complete course may induce severe adverse effects, such as
bone marrow suppression, liver and kidney function disorder and
a lowered immunological function [37]. This may possibly limit
the adequate dosage, and decrease the therapeutic effects. As the
tumor developing, the tumor-derived factors may also have harmful
impact on the immune system of hosts [38]. Therefore the
immune system plays an important role in fighting against tumorigenesis.
Now, many reports about immunoenhancement, the body
resistance-strengthening and antitumor activities of the polysaccharides
from traditional Chinese herbs medicines have attracted
more and more attention [39,40]. The results of the present investigation
demonstrate CSP from corn silk significantly inhibited the
tumor growth and extended the survival time of mice bearing H22
hepatocellular carcinoma. The antitumor activity of CSP was in a
dose dependent manner, with no signs of toxicity to weight, kidney
and liver. Furthermore, peripheral WBC count, thymus index
and spleen index of H22 tumor-bearing were also improved. In
addition, CSP administration could significantly increase the production
of serum IL-2, IL-6 and TNF- in mice bearing H22 tumor.
The increase may also explain the antitumor properties of this
polysaccharide. Based on the results of the present study, it can
be suggested that the antitumor activity of CSP might be at least in
part due to immune function activation. But the molecular mechanism
by which CSP imparts cancer chemopreventive effects has
not been clearly defined and further studies are needed.