Experimental Treatments May Delay Liver Failure
Although the two therapies take fundamentally different approaches to
treating potentially fatal liver diseases, each attempts to prolong the useful
lives of liver cells in order to correct liver damage or delay liver failure,
say lead researchers in separate interviews with WebMD.
In the first study, researchers at Harvard Medical School in Boston and the
Albert Einstein College of Medicine in New York report that cirrhosis of the
liver -- and perhaps some other progressive, fatal diseases -- could be slowed,
stopped, or even prevented with genetic therapy. Cirrhosis is the potentially
fatal scarring of the liver, which can lead to liver failure. According to the
National Institutes of Health, cirrhosis of the liver is the seventh leading
cause of death by disease in the world.
Many diseases such as cirrhosis are characterized by a high, ongoing rate of
cell death and an organ's inadequate ability to reproduce its cells, according
to Ron DePinho, MD, American Cancer Society research professor at the Dana
Farber Cancer Institute at Harvard Medical School. Decades of this kind of cell
turnover can result in liver failure, he says.
He and his colleagues found evidence that showed cirrhosis of the liver
might be related to damage to the genetic material DNA. The liver has a
remarkable capacity to grow new cells, and the researchers surmised that this
DNA damage may lead to destruction rather than regrowth of liver cells.
The researchers tested a form of gene therapy in mice that were bred to have
the abnormal DNA that scientists felt was related to the development of
cirrhosis. A normal copy of the gene was injected into the mice and the treated
mice had restored normal DNA function and near-normal liver cell growth as well
as an improvement in liver function.
In the second study, researchers in Japan and the U.S. were able to
genetically alter normal human liver cells so that they would continue to
reproduce indefinitely. The researchers then transplanted the human cells into
rats with liver failure. The rats were treated with immune-system suppressing
drugs to prevent the rats from rejecting the human cells. Almost all of the
rats had significant improvement in their liver function. The transplanted
cells apparently provided sufficient life-saving support for the rats' severely
damaged livers to regenerate.
Principal investigator Philippe Leboulch, MD, PhD, assistant professor of
medicine at Harvard Medical School and a physician at Brigham and Women's
Hospital in Boston, tells WebMD that this therapy, if proven to be safe in
humans, could buy crucial time for patients in liver failure. Leboulch is also
a researcher at Massachusetts Institute of Technology in Cambridge.
Leboulch collaborated on the study with colleagues at Okayama University
Medical School in Okayama, Japan, and the University of Nebraska Medical Center
- Researchers are developing genetic therapies that can buy more time for
liver patients as they wait for an available donor organ or until they can heal
on their own.
- Some therapies aim to slow the progression of liver disease by restoring
normal genetic function to the organ.
- Other therapies try to extend the life of healthy liver cells so that liver
function can continue.