In what could be a breakthrough in cancer therapy, researchers report in The New England Journal of Medicine today that they succeeded in bolstering a patient's immune system enough to wipe out late-stage malignant tumors on its own. The scientists say the successful experiment could pave the way for new treatments of advanced cancer that spare patients the side effects of chemotherapy, which kills healthy as well as malignant cells.

This is not the first time that researchers attempted to use immunotherapy—or a patient's own infection-fighting cells—to try to destroy tumors. But researchers at the Fred Hutchinson Cancer Research Center in Seattle say this is the first time such a therapy worked on its own, without combining it with drugs or chemotherapy.

Lead study author Cassian Yee, an immunologist, says that he and his team removed so-called CD4+ T cells (a type of infection-fighting white blood cell) from a 52-year-old man with stage IV (the most advanced) melanoma—the deadliest form of skin cancer; it had spread to a lung and a groin lymph node. The researchers grew T cells (that target a specific protein, or antigen, on the tumor cells) in the lab until they had a population they believed was large enough to destroy the cancer.

They infused five billion of the cloned cells into the patient. Two months later, PET (positron emission tomography) and CT (computed tomography) scans did not reveal any tumors—and the patient has remained disease-free for two years, Yee says.

"This is the first example that I can think of where someone actually grew CD4+ T cells outside the body and gave [them] back and got results," says Willem Overwijk, an immunologist at the University of Texas M.D. Anderson Cancer Center in Houston, who was not involved in this study.

Both Yee and Overwijk describe the CD4+ T cells as "helper" T cells, because they are known to trigger other T cells in the body to grow. Among the cells they affect are so-called killer T cells (or CD8+ T cells) that attack tumor cells.

Yee says the injected T cells remained active in the patient's body for at least 80 days—and that the tumors vanished even though only 50 to 75 percent of their own cells released the targeted protein or antigen (known as NY-ESO-1).

"This shows that we were able to broaden the immune response to other tumor [proteins], possibly by harnessing the [T cells] already present in the patient," Yee says.

Although pleased with the results, Yee cautions that the approach thus far has only been tested in one patient. He plans to conduct a larger trial on 10 to 20 patients over the next year or so. If that trial—and subsequent ones are successful—he says the therapy could be a viable treatment option within five years.

4 Comments

1. 1. Retired RN 04:56 AM 6/19/08

   This isn't new. Check the link "T Cell Triumph" above. There was an expanded article in Oncology Times from 2002 that describes separating T cells and growing them for re-infusion into cancer patients. One patient, a sixteen year old boy with advanced melanoma had been in remission for two years at the time this article was written.

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2. 2. johnwnorton 12:32 AM 6/20/08

   This article may be inaccurate. In an Associated Press story (dated 6/19/08) about this study, it is reported that the patient showing success was one of nine patients in the study. The other patients showed no success. The story further stated that the researchers have lost contact with the patient and his current health status is unknown. Any conclusion about one patient in such a small study is not worth the ink. Scientific American editors should show more restraint.

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3. 3. scicell 03:26 PM 7/8/08

   
   I suggest that the 3-d nature of solid tumors be considered in further analysis.
   
   The data may indicate a 3d cell differentiation in the tumor.
   The infused cells first destroyed the tumors protective cell layer thus permitting attack by other non-infused t-cells.
   
   It has been reported before in studies of the 3-dimenional nature of solid tumors, that there is a fast growing outer cell layer and slower growing inner layers undergoing, apoptotic processes - dying, calcification.
   
   The data may indicate that after 20 - 30 days the infused cells broke through this protective layer.
   At which point non-infused t-cells were able to attack the inner (once protected layers) of the tumor.
   
   These protected layers would not initially show any blood-derived immune response because the fast growing cells that were the subject of the specified t-cell attack protected them.
   
   Once the specified attacking cells broke through [this seems the key], the patient's other non-infused t-cells were able to mount a final attack that that completely destroyed the whole tumor.
   
   Thus it does seems from the data that a "chink in the amour of the solid tumor has indeed been discovered.
   
   It therefore seems important to:
   1. Increase the dose of infused cells so that the t-cell attack overwhelms the fast growing layer. It seems a competitive process - the number of "tumor specific attacking t-cells relative to the number of fast growing tumor cells of the outer layer, which try to replace the tcell damaged or destroyed tumor cells.
   
   2. Sample, (maybe using a needle) the tumor cell types in a 3-d manner. Because the inner cells (from the data) appear to be different and more susceptible to attack than the fast growing outer layer of the solid tumor.
   
   3. Consider, the risk of sampling just the blood, which is in contact (presumably), mainly with the outer layer.
   It may give, only, an immune response for the fast growing outer tumor cell type.
   
   It seems to me that the tumor has a protective "skin" not unlike the skin from which the solid tumor was derived.
   
   It is likely that the 8 patients' tumors did not achieve a breakthrough of the outer fast growing layer - either because the attacking t-cells were the wrong ones for their tumors, or because of an insufficient quantity of the specified infused t-cells.
   
   It seems to me that the data may be giving a beautiful (even if second hand) image of the 3-d nature of the solid tumor.
   
   In any case, the result as described may be (is likely) important  the tumor likely has a chink in its amour!
   
   God bless and guide you in defeating these dastardly human malfunctions.
   

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4. 4. Chestnutblossom in reply to scicell 08:25 AM 4/28/09

   Hallo,
   
   I would very much like to know who the author "Scicell" is, what his qualifications are and how I could reach him/her beyond this limited space. I am a breast cancer patient after an operation, suffering a lot from chemo-therapy at the moment. The doctors tell me, 6 1/2 weeks of radiation will also be necessary immediately after. Will anything be left of me by the end of all this? I am already very, very exhausted and have been suffering already too much from pain during this treatment.
   
   Also it seems that my type of cancer is very aggressive and has a high tendency to metastases. I gather that from what the doctors tell me, moreover I had an additional test of tumor tissue privately done in a laboratory working for Dr. Coy and his firm Tavarlin. The result was that 80% of my tumor cells procuce TKTL1, an enzyme discovered in 2005 by Dr. Coy which changes the tumor cells in more aggressive ones that are likely to produce metastases soon. You can imagine that I am highly interested in the progress of immunology and would be very thankful for every hint, address, informotion.
   Yours faithfully
   Irmtrud Koch

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