An experimental treatment that genetically alters a patient’s own immune cells, or T-cells, to fight cancer has produced remissions in adults with a deadly acute leukemia. This type of blood cancer is worse in adults than in children, the cure rate in adults is about 40 percent, compared with 80 to 90 percent in children. The experimental treatment uses a patient’s own T-cells, a type of white blood cell that normally fights viruses and cancer. The patient’s T-cells are extracted and genetically engineered using a disabled virus as a vector to carry new genetic material into the cells. The altered T-cells recognize and kill any cell that carries protein CD19 on its surface. CD19 is found on B-cells, which are part of the immune system. The patients in the study had a type of leukemia that affected B-cells, so the goal was to train the patients’ T-cells to destroy B-cells. Healthy B-cells would be killed along with cancerous ones, but that side effect is treatable.
Patients, who have relapsed after chemotherapy, usually have only a few months left. Three of the five patients that took part in this study have been in remission for 5 to 24 months. Their prognoses were good, but relapse was still possible, only time will tell. One patient from this study, 58 year old David Aponte was left in remission eight days after receiving the experimental treatment. Before any treatment Aponte agreed to his oncologist, Dr. Brentjens, suggestion that before starting chemotherapy Aponte have some of his T-cells removed and stored because chemotherapy would deplete the T-cells and he would no longer have the option to take part in the experiment if he were to relapse. After relapsing he joined the study. For the first few days nothing was happening. Then, his temperature began to rise, his fever spiked to 105 degrees. His T-cells were in a violent battle with the cancer and were churning out enormous amounts of hormones called cytokines. What was taking place is called a cytokine storm. The hormonal rush caused his blood pressure to plunge and his heart rate shoot up. Mr. Aponte was treated with steroids to subdue the reaction and eight days later, his leukemia was gone. After remission he was given a bone-marrow transplant, the normal and most promising treatment for this disease. Experts consider this treatment a highly promising approach for a variety of lethal cancers, including other blood cancers and tumors in organs like the prostate gland.
http://www.nytimes.com/2013/03/21/health/altered-t-cell-therapy-shows-promise-for-acute-leukemia.html?ref=geneticengineering
This article got my attention by the word Leukemia. Leukemia is a malignant cancer that is in the blood or bone marrow and produces abnormal amounts of blood cells. Having acute leukemia means the cells are rapidly progressing. I have a few friends and family members that have this cancer and it is saddening to see them in pain. I know many people going through chemotherapy with leukemia and other types of cancer and this is even worse to see. Chemo makes people extremely weak while not even making one better. In the future there will probably be cures for cancer that will cure it right away. Right now we keep trying all these cures that are only a tiny bit better than the last. Although the cell therapy seems to be better than chemo, it is still affecting the healthy blood cells. Also, cell therapy is only helping somebody live for a little longer than chemo does, according to this article. This is the only beneficial thing about this treatment, but do we want to keep somebody who is suffering alive longer to make them suffer even more? I also do not think this is a good idea because these cells are being taken from animals. A person can get a bacterial or viral infection from the animal cells being injected, and some people can get life threatening allergic reactions. There have been serious immune system reactions resulting in death from cell therapy. I think we can come up with better cures, we just have to wait for the right one to be discovered.
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