Gene Therapies Show Promise in Cancer
Experimental Drug That Targets Tumors at Their Roots Also Shows Signs of Success
Gene Therapy Targets Lung Cancer
Researchers at the University of Texas M.D. Anderson Cancer Center in
Houston are trying a different tactic, packaging a cancer-suppressing gene in a
fat-based coating for protection.
So far, they have successfully delivered the cancer-killing gene into the
tumors of 13 people with advanced lung cancer.
In the three people in whom biopsies were performed before and after
treatment, "we saw expression of the infected gene and signs the tumor [had
stopped growing]," says researcher Charles Lu, MD, associate professor in
the department of thoracic, head and neck medical oncology.
They lived an average of 14.6 months, which compares favorably to the
typical seven-month average for people with this stage of disease, Lu says.
"Still, it is way too early to draw conclusions," he tells WebMD.
Lu says the work built on the observation that a copy of the cancer-killing
gene, FUS1, is lost in people with lung cancer.
"By reinjecting the gene that was lost, we get tumor suppression
again," he says.
The only significant side effect so far has been fever, which is treatable,
Lung cancer is the leading cause of cancer death in the U.S., causing
160,000 deaths annually, according to the American Cancer Society.
Experimental Drug Shows Promise in Brain Cancer
In other research presented at the meeting, an experimental pill showed
promise in treating one of the deadliest types of brain cancer.
The pill blocks the growth of new blood vessels that feed tumors. By
eliminating the flow of blood to tumors, the idea is to prevent the tumor from
People with the cancer, glioblastoma, "secrete a lot of growth factors
that make blood vessels that feed the tumor, so this is an attractive
target," says researcher Tracy Batchelor, MD, chief of neuro-oncology at
Massachusetts General Hospital in Boston.
The researchers gave the drug, known as AZD2171, to 31 people who had failed
to respond to radiation, chemotherapy, and surgery.
Within 24 hours, "leaky blood vessels began to normalize," Batchelor
tells WebMD. Also, swelling in the brain, a big problem in such patients, was
But by one month later, abnormal blood vessel growth resumed, imaging
studies showed.Still, tumors shrank by 50% or more in half of the participants,
and the average time to tumor regrowth was 111 days. In contrast, only about
one in 10 people with glioblastoma given traditional treatment typically have
tumor shrinkage, and the average time to progression is usually 63 days,
"We all recognize that what we need to do now is combine this therapy
with other types of treatments, either existing or to be developed, and to
deliver these drug combinations during the window we have identified,"
Batchelor says. "This might help us manage patients much more
He says the researchers hope to start a larger trial in which participants
get either AZD2171 plus standard chemotherapy or chemo alone within the