Gene Therapies Show Promise in Cancer
Experimental Drug That Targets Tumors at Their Roots Also Shows Signs of Success
Gene Therapy Targets Lung Cancer continued...
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, he says.
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 growing.
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 alleviated.
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, Batchelor says.