Gene Therapy for Cancer Treatment - Biotechnology and Your Health: Pharmaceutical Applications - page 105

cells. In addition, if large double-stranded RNA is delivered to a
whole animal, it will activate some immune system responses.
Researchers are trying to learn how to use appropriate doses of
small interfering RNA ( siRNA ) in animal experiments to treat certain
cancers, liver damage caused by virus infections, shock caused by
potentially lethal bacterial infections, and possibly HIV. The poten-
tial of siRNA seems very great, but only careful tests in whole animal
model systems and human trials will eventually prove whether
this seemingly surgically precise molecular clipper can work.
Stop and Consider
Why are cancer cells attractive candidates for gene-specific therapies?
CONNECTIONS
Over the last few decades, several types of gene-directed strategies
have been proposed as cancer treatments, based on scientists'
understanding of the genetic changes in tumor cells that allow
them to grow out of control. Despite many years and many trials,
gene therapy, antisense, and ribozymes have so far failed to provide
a useful anticancer drug. Newer approaches, particularly siRNA,
are currently poised for critical testing. Experience with older
approaches may provide lessons for researchers that increase the
chances for success against cancer—one of our most formidable
medical adversaries.
FOR MORE INFORMATION
For more information about the concepts discussed in this chapter,
search the Web using the keywords:
cancer genes , oncogenes , tumor suppressor genes , angiogenesis , small
interfering RNA