Organ-targeted cancer chemotherapy, stealth viruses designed to maneuver through the immune system, even "bio-bypass" treatment of atherosclerosis without surgery -- all are on the medical horizon, the "Father of Gene Therapy" Ronald Crystal, M.D., said at the 12th Annual Biotechnology Symposium on Oct. 15 on campus.
Gene therapy for cystic fibrosis is only the beginning, according to Crystal, the Webster Professor of Internal Medicine and chief of pulmonary and critical care medicine at New York Hospital-Cornell Medical Center. He was joined by Gregory Petsko of Brandeis University and Robert Langer of Massachusetts Institute of Technology at the symposium, titled "Frontiers in Biomedicine" in the Biotechnology Building.Crystal was introduced by Lynn Jelinski, director of Cornell's Center for Advanced Technology in Biotechnology, as gene therapy's progenitor for his pioneering experiments in treatment of cystic fibrosis. He recounted the risks and excitement of the highly experimental procedures and showed a picture of himself attending the first human patient.
"If it looks like I'm praying, there was good reason," Crystal said. He was spraying approximately 2 million live adenoviruses (the vector for cystic fibrosis transmembrane conductance regulator or CFTR genes) into the man's lungs. And 1,000 adenoviruses are enough to cause pneumonia.
The experiment was successful, in part because the viruses had been rendered replication-deficient, which is one strategy to keep an "Andromeda strain" of super viruses from taking over the patient or the planet. Crystal likened his gene-therapy approach to the process that turned four pet reptiles into the first and last of the Teenage Mutant Ninja Turtles.
"We are using genes as a drug to change the genetic repertoire of (an individual's) cells," Crystal said of somatic gene therapy. "The individual cannot pass on the genome to the progeny. Gene therapy has a lot of social and ethical implications," he added. "It can cure the individual but not change mankind."
Gene therapy will allow chemotherapy precisely for the cancerous organ and not other parts of the body, Crystal said, "to limit toxic effects to the local milieu." To work with the cellular immune system, it should be possible to develop "stealth viruses" as vectors for genes, he noted.
And adenoviruses will be used to carry genes for blood vessel growth factor directly into the heart of patients suffering clogged arteries.
"Bio-bypass" therapy to grow new blood vessels -- an alternative to surgical bypass procedures with balloons to clear arteries -- will be tested in humans within a year, Crystal said.
The symposium was sponsored by the Center for Advanced Technology in Biotechnology.