9/13/2011 PERMALINK
Modded T cells cure leukemia. In a cancer treatment breakthrough, researchers from the University of Pennsylvania's Abramson Cancer Center and Perelman School of Medicine have shown sustained remissions of up to a year among a small group of advanced chronic lymphocytic leukemia (CLL) patients thanks to genetically modded versions of their own T cells. Patients' cells were removed and modded in Penn's vaccine production facility, then infused back into the patient's body. The findings are the first demonstration of the use of gene transfer therapy to create "serial killer" T cells aimed at cancerous tumors. "Within three weeks, the tumors had been blown away, in a way that was much more violent than we ever expected," said senior author Carl June, MD, director of Translational Research and a professor of Pathology and Laboratory Medicine in the Abramson Cancer Center, who led the work. "It worked much better than we thought it would." The response of one 64-year old patient was typical. Prior to his T cell treatment, his blood and marrow were replete with tumor cells. For the first two weeks after treatment, nothing seemed to change. Then on day 14, the patient began experiencing chills, nausea, and increasing fever, among other symptoms. Tests during that time showed an enormous increase in the number of T cells in his blood that led to a tumor lysis syndrome, which occurs when a large number of cancer cells die all at once. By day 28, the patient had recovered from the tumor lysis syndrome - and his blood and marrow showed no evidence of leukemia. "This massive killing of tumor is a direct proof of principle of the concept," says co-principal investigator David Porter, MD, professor of Medicine and director of Blood and Marrow Transplantation. Estimates are that the newly lethal modded T cells killed 2 pounds of cancer cells.