More than 37,000 people in the United States will be diagnosed with pancreatic cancer this year, and nearly all of those cases will be untreatable. Now, scientists have developed a gene therapy that kills pancreatic tumors in mice by causing the tumor cells to commit suicide.
Gene therapies often use crippled viruses to deliver therapeutic genes into a patient's cells, but injecting these modified viruses into people can be risky. For example, a patient in a 1999 gene therapy trial died from a severe immune reaction that scientists suspect was caused by the delivery virus.
To avoid such problems, Mien-Chie Hung and his colleagues at the M.D. Anderson Cancer Center in Houston packaged a self-destruct gene inside microscopic bubbles called liposomes. These bubbles, measuring 100 to 200 nanometers across, are roughly the size of viruses and have surfaces made of fat molecules similar to those in cell membranes. When liposomes touch cells in a patient's body, they can easil