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- MEDICINE, Page 82Using Cancer to Fight Cancer
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- A high-profile researcher plans to inject patients with their
- own genetically altered tumor cells
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- For people facing terminal cancer, word of a possible new
- treatment is a beacon of hope. Few scientists have scattered
- more rays than Dr. Steven Rosenberg, who has conducted a series
- of tantalizing though as yet inconclusive experiments at the
- National Cancer Institute. Rosenberg, a surgeon by training, has
- repeatedly tried to find new ways to rally the immune systems
- of cancer patients to combat their own disease. Last week he
- revealed his most radical effort to date: vaccinating injected
- patients with their own genetically altered tumor cells in what
- Rosenberg calls an attempt "to immunize the patient against his
- own cancer."
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- Widely covered by the press, the procedure prompted dozens
- of phone calls to the NCI from patients desperately seeking a
- cure. Rosenberg stresses, however, that his work is highly
- experimental. The treatment puts a new twist on classic vaccine
- strategy. "When you think of a vaccine, it's usually to prevent
- a disease," he explains. "Here we're actually treating an
- advanced cancer."
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- The first two patients -- a 46-year-old man and a
- 30-year-old woman -- both have terminal-stage melanoma, a form
- of skin cancer. A few months ago, doctors extracted tumor cells
- from the patients and inserted into the cells the gene that
- promotes the production of an antitumor hormone called tumor
- necrosis factor (TNF). The genetically altered cells were grown
- in a lab and then injected last week into the thigh of each
- patient. The hope is that the TNF-primed cells will boost the
- body's immune system into more vigorous attack against the
- malignancy.
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- In a second stage of the treatment, two weeks from now,
- doctors plan to remove white blood cells from the injection
- sites and nearby lymph nodes, grow them in a lab and transfuse
- them into the patients. Studies suggest that such cells will
- have developed a strong antitumor activity.
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- Rosenberg and his team have permission from the National
- Institutes of Health and the Food and Drug Administration to
- treat 15 people with TNF-gene-altered cells, including patients
- with advanced kidney or colon cancer. Another 15 individuals
- with the same diseases may receive injections of tumor cells
- that have been genetically altered to produce interleukin-2 --
- a protein that stimulates tumor-fighting lymphocytes -- instead
- of TNF. All the patients have failed to respond to standard
- therapy.
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- As promising as the approach sounds, some researchers are
- disturbed by Rosenberg's announcement. They argue that a human
- trial is premature, given the limited results of this treatment
- in animals. While Rosenberg's method has been shown to prevent
- the formation of new tumors in healthy mice, there is no
- published evidence that it can counteract existing cancers.
- Rosenberg, however, maintains that he has ongoing animal
- experiments to support his work and that he submitted extensive
- unpublished research data before obtaining permission to
- proceed: "This was reviewed for eight months by about 50
- scientists on at least five committees at the NIH and FDA."
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- Rosenberg has also been criticized for inflating patients'
- hopes by publicizing his experiment before there are any results
- to report. "It's a very high-profile research activity that
- Steve Rosenberg is running," Dr. Philip Leder of Harvard
- University School of Medicine told the New York Times. "He
- didn't come to you after the experiment was successful. He came
- at the beginning, because it might be quite uninteresting when
- it's all finished." Given all the attention and elevated hopes,
- Rosenberg should reveal his results -- even if they are
- uninteresting -- with the same alacrity he shows in announcing
- the start of an experiment.
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- By Anastasia Toufexis.
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