Scientists describe the first successful use of a human patient’s cloned infection-fighting T-cells as the sole therapy to put an advanced solid-tumor cancer into long-term remission. A team led by Dr. Cassian Yee, in the Clinical Research Division, reports these findings in the June 19 issue of the New England Journal of Medicine.
Yee and colleagues removed CD4+ T-cells, a type of white blood cell, from a 52-year-old man whose stage 4 melanoma had spread to a groin lymph node and to a lung. T cells specific to targeting the melanoma were then expanded vastly in the laboratory using modifications to existing methods. The lab-grown cells were then infused into the patient with no additional pre- or post-conditioning therapies, such as growth-factor or cytokine treatment. Two months later, PET and CT scans revealed no tumors. The patient remained disease free two years later, when he was last checked.
”We were surprised by the anti-tumor effect of these CD4 T-cells and its duration of response,” Yee said. “For this patient we were successful, but we would need to confirm the effectiveness of therapy in a larger study.”
Yee cautioned that these results, presented in the journal’s “Brief Report” section, represent only one patient with a specific type of immune system whose tumor cells expressed a specific antigen. More studies are needed to confirm the effectiveness of the experimental T-cell therapy. If proven successful in more patients, Yee predicted this therapy could be used for the 25 percent of all late-stage melanoma patients who have the same immune-system type and tumor antigen.
The patient in the journal report was one of nine patients with metastatic melanoma who were being treated in a recently completed clinical trial to test dose- escalation of autologous CD4+ T-cells.
Using a patient’s own immune system to combat cancer, called immunotherapy, is a growing area of research that aims to develop less-toxic cancer treatments than standard chemotherapy and radiation.
Researchers in Yee’s lab, the University of Washington School of Medicine and the Ludwig Institute for Cancer Research in New York collaborated on the research. The Burroughs-Wellcome Foundation, Damon Runyon Cancer Research Foundation, Edson Foundation and National Cancer Institute funded the study. Read more about the study "In the News" at http://fhcrc.org/about/ne/news/2008/06/18/T_cells.html.