Colorectal cancer is the second leading cancer killer in the United States. The American Cancer Society estimates that 147,500 cases of colorectal cancer will be diagnosed in the country in 2003 and 57,000 people will die from the disease.
In experiments with laboratory animals, Mount Sinai researchers have demonstrated that their approach to gene therapy, known as tumor immunization, extended life in all animals tested and wiped out cancer entirely in up to 20% of animals whose cancer had spread from the colon to the liver.
"Cancer cells are able to grow unimpeded by the body's defenses because they look very similar to healthy cells, with only very subtle differences that pass under the radar screen of the body's immune cells," said Savio Woo, PhD, Director of the Carl C. Icahn Center for Gene Therapy and Molecular Medicine at Mount Sinai School of Medicine. "We use gene transfer technology to insert a gene into the cancer cells that makes them visible to the body's natural immune defenses."
The method of tumor immunization which Mount Sinai researchers developed involves transferring a gene that codes for Interleukin-12 (IL12) into cancer cells directly in the patient's tumor. IL12 is a protein that is not normally produced by cancer cells. When the cancer cells produce this protein as a result of gene transfer it acts as a signal to a special class of white blood cells of the immune system telling them, "These cancer cells are dangerous. Come over here and destroy them."
The laboratory and animal studies conducted by Dr. Woo and colleagues have provided evidence that delivering the IL12 gene to cancer cells can trigger a targeted immune response that destroy
Contact: Debra Kaplan
The Mount Sinai Hospital / Mount Sinai School of Medicine