Cloned Immune Cells Cure Skin Cancer

A new study describes how a patient whose skin cancer had spread throughout his body was cured and given the all clear after being injected with billions of his own immune cells.

Researchers at the Fred Hutchinson Cancer Research Center (Seattle, WA, USA) developed an in vitro method for isolating and expanding autologous CD4+ T-cell clones with specificity for the melanoma-associated antigen NY-ESO-1. They then extracted immune cells from a 52-year-old patient with refractory metastatic melanoma who had not undergone any previous conditioning or cytokine treatment, and went on to replicate these cells until they had more than 5 billion of them; the cloned cells were then infused back into the patient. As soon as the cells entered the patient, they immediately began attacking the cancer, and also led to concomitant endogenous responses against other melanoma antigens, attacking all the cancer cells in the body. The treatment mediated a durable clinical remission, and two months later medical scans failed to pick up any signs of cancer in the patient. The study was published in the June 19, 2008, edition of the New England Journal of Medicine (NEJM).

"What we and others have thought might be important is that we need to give patients more of these cancer-fighting T cells which may be present in low frequency in most people,” said lead author Cassian Yee, M.D., a translational scientist at the Fred Hutchinson Cancer Research Center. "You can do that either by giving them a vaccine or, in our case, we took the cells out and grew them and gave them back to him.”

The team believes the treatment could be effective in around a quarter of skin cancer patients whose immune systems have cells that are already primed to attack their tumors; however, the researchers cautioned against undue optimism and pointed out that they had tried the same T cell approach on eight other patients, none of whom has had the same success.

"We are hoping to expand this study, but because it's very expensive and it takes several months to grow the T cells, only a very, very small number of patients would be eligible for the trial,” added Dr. Yee. "We have far more requests than we can handle and so we are primarily interested in seeing what the next step might be in improving therapy.”


Related Links:
Fred Hutchinson Cancer Research Center