Breakthrough in Using Immune System to Fight Cancer Through Gene Therapy
Researchers have long hoped to use the human immune system to kill malignant cancer cells. A new study in The New England Journal of Medicine suggests scientists at the University of Pennsylvania may have made significant strides in that approach using experimental gene therapy.
William Ludwig, a retired corrections officer from Bridgeton, N.J., volunteered for the experimental cancer treatment, because his chemotherapy had stopped working and he had few options, according to an article in The New York Times. Today, a year after the novel treatment, Ludwig’s chronic leukemia is in complete remission and he is playing golf and working in the yard. The same approach may work with other cancers besides leukemia, doctors say.
As part of the experimental treatment, the doctors removed a billion of Ludwig’s T-cells, white blood cells that fight viruses and malignant cells, and re-engineered them. They exposed the T-cells to a disabled form of the HIV-1 virus, which genetically altered the T-cells. They reprogrammed the T-cells to hone in on Ludwig’s leukemia and to reproduce in large numbers when activated by chemicals produced by malignant cells. They then reintroduced the T-cells into Ludwig’s blood.
Initially, Ludwig suffered flu-like symptoms such as a temperature and chills as the T-cells reproduced. The T-cells multiplied to 1,000 to 10,000 times the number infused, wiped out the cancer, then gradually diminished, leaving a rear guard of T-cells that can proliferate again if they sense more malignant cells. After a few weeks, Ludwig’s flu symptoms disappeared and there was no trace of the leukemia.
The doctors caution that the treatment is still experimental and are not yet claiming that Ludwig is cured. But a similar approach may work for treating other forms of cancer, the doctors say. Dr. Carl June, head of the research team at the University of Pennsylvania, plans to try the treatment approach on solid tumors produced by cancers such as ovarian cancer, pancreatic cancer and mesothelioma. Mesothelioma is an aggressive cancer of the lining of the lungs and abdomen closely associated with exposure to asbestos.
Approximately 2,500 to 3,000 people are diagnosed with mesothelioma each year in the United States. Many sufferers are retired workers and veterans who were exposed to asbestos decades ago, even if they didn’t realize it. Symptoms of mesothelioma typically appear 20 to 50 years after exposure, making the diagnosis more difficult.