BEIJING, July 14 (Xinhuanet) -- U.S. researchers have
developed molecular "smart bombs" that prevent pancreatic and kidney cancer from
spreading in mice while causing fewer side effects and damage to healthy
surrounding tissues than traditional chemotherapy.
A team from the University of
California, San Diego, designed a "nanoparticle" anti-cancer drug delivery
system that zeros in on a protein marker called integrin avB3, which is found on
the surface of certain tumor blood vessels. The marker is tied to the
development of new blood vessels and malignant tumor growth.
While the system had little impact on primary tumors,
it halted the metastasis of pancreatic and kidney cancers throughout the bodies
of mice. Cancer metastasis normally is much harder to treat than the primary
tumor, and it usually leads to the patient's death.
"We were able to establish the desired anti-cancer effect
while delivering the drug at levels 15 times below what is needed when the drug
is used systemically," study leader David Cheresh, vice chairman of pathology at
UCSD, said in a university news release. "Even more interesting is that the
metastatic lesions were more sensitive to this therapy than the primary tumor."
According to the report, the system works with a
lower dose of chemotherapy because it attacks the cancer with such precision. In
most chemo treatments, the destruction of healthy tissue is a side effect as it
floods the body with cancer-killing toxins.
UCSD engineers and oncologists together designed the
nanoparticle -- a microscopic particle made of lipid-based polymers -- to work
with the cancer-killing drug doxorubicin.
"Doxorubicin is known to be an effective anti-cancer
drug but has been difficult to give patients an adequate dose without negative
side effects," Cheresh said. "This new strategy represents the first time we've
seen such an impact on metastatic growth, and it was accomplished without the
collateral damage of weight loss or other outward signs of toxicity in the
patient."
(Agencies)
