'Robocop' Stem Cells Developed to Fight Cancer

Cancer is the second-leading cause of death in the United States, although due to several advancements in cancer screening and treatment, survival rates have begun to improve.

A new cancer therapy

Researchers at the University of Minnesota and Mayo Clinic have developed a new type of cancer therapy that involves a personalized approach to fighting off cancer. The new cellular therapy, known as CAR T, involves removing a patient’s white blood cells, having them genetically modified in a laboratory, and then infusing them back into the patient’s body. The researchers say that they hope to find out whether patients with lymphoma or leukemia can benefit from higher survival rates if their own stem cells are removed from their bodies and then placed back with cancer-fighting T-cells. Such T-cells are expected to aim at destroying CD19 proteins, which can be found on the surface of B-cells.

Stepping away from chemotherapy

“This is really the first approval of a genetically modified product for cancer therapy. We might be on the right track to get away from all of the toxic chemotherapy that people hate” said Dr. Jeffrey Miller, deputy director of the Masonic Cancer Center at the University of Minnesota. The CAR T cellular therapy is expected to receive federal approval by the U.S. Food and Drug Administration for blood cancers that are uncommon – more specifically B-cell forms of lymphoma and leukemia cells. “I often tell patients that T-cells are like super robocops. We are directing those cells to really target cancer” said Dr. Yi Lin, a hematologist at Mayo Clinic in Rochester, Minnesota.

One particular study found an increase in the percentage of cancers that disappeared in lymphoma patients who received CAR T cellular therapy instead of traditional treatment involving chemotherapy. However, the side effects have proven to be harsh. T-cell infusions have been found to cause symptoms such as weakness, fever, rapid heart activity, short term memory, kidney problems and cognitive problems. In fact, five deaths occurred in cancer patients who participated in a CAR T trial by Juno Pharmaceuticals, due to brain swelling. As a result, the trial was terminated. Dr. Yi Lin said that the brain swelling was seen mainly in individuals with leukemia; however, for now, she expects approval for CAR T cellular therapy in diffuse large B-cell lymphoma, as well as for Novartis therapy in acute lymphoblastic leukemia in children. Moreover, federal regulations may restrict further use of CAR T cellular therapy in patients who survived cancer from undergoing traditional treatments.

Successful result after many failures

Before taking part in a clinical trial for CAR T cellular therapy, John Renze of Carroll, Iowa had received two sessions of radiation, two sessions of chemotherapy, and an experimental drug that had no effect on the cancer. The 58-year-old stated “After you fail about four times, you start to wonder if anything is going to work.” Renze’s stem cells were removed in July and the modified T-cells were infused within his body after 30 days. He experienced side effects such as weight loss and nausea for weeks, leading him to drive to Mayo for frequent check-ups. However, in August, researchers had noticed that his cancer had completely disappeared. Now, he returns to Mayo for a check-up every three months to make sure that the cancer has not resurfaced. “For people like me that have already failed a bunch of times, you’re happy to try anything. I mean, what else would I have done?” said Renze.

What happens if or when it’s approved?

Mayo researchers expect hundreds of cancer patients to participate in CAR T cellular therapy per year, once the therapy is approved. They also expect large medical facilities to initially offer the therapy because they are well-equipped for handling the process of the therapy and any side effects that might emerge from it. More specifically, the Rochester Hospital in Minnesota is preparing to add staff members and a section committed to CAR T cellular therapy. Dr. Jeffrey Miller said the University of Minnesota is developing recommendations for doctors and hospitals on a state level, so that they are aware of how to react if patients should show up with complex symptoms from CAR T cellular therapy. “They can be a bit delayed and you can’t just keep people in the hospital to see if they develop these things,” he said. Mayo experts are also researching whether CAR T cellular therapy can work to prevent bone marrow cancer known as multiple myeloma. Furthermore, they are studying to understand ways in which CAR T cells can be placed in cancer patients and whether CAR T triggers any immune system responses if there is a possibility that cancers should resurface.

With CAR T cellular therapy, around 80,000 blood cancers can be treated in the United States on an annual basis. Even before receiving federal approval, researchers like Miller are looking at CAR T cellular therapy to determine how such a personalized approach can have an effect on solid tumors. The challenge remains in the difference between targeting proteins in solid tumors and blood cancers. If the solid tumors are to be destroyed, they need to be infused with more discriminating T-cells. “If you destroy normal lung tissue (along with lung cancer), that’s not going to work,” said Miller. Dr. Miller is also studying whether targeting cancer can be done by genetically modifying and infusing NK cells as opposed to T-cells. Since the human body does not reject NK cells from donors that often, there might be a possibility to provide a quicker and more cost-effective treatment approach.

Pricy setbacks

CAR T cellular therapy, like many other innovative therapies, will be pricey to implement. The price is expected to go beyond $200,000 for each patient. As to how exactly insurers will cover costs remains unclear, yet the coverage policy following FDA approval is beginning to be reviewed. What is evident is the effectiveness of the therapy in treating cancer. CAR T is less likely to reject T-cells that are genetically modified and infused back into patients’ bodies. “It’s individualized medicine” said Dr. Yi Lin.

Cancer is a general term used to describe a large group of diseases which are portrayed by the development of abnormal cells that divide quickly and damage normal body tissue. Cancer has the ability to spread to other tissue and organs throughout the body. In a healthy human body, cells have a specific life cycle that involves them growing and dividing normally. New cells grow in the place of damaged or old cells when they die. However, cancer obstructs this process by causing mutation changes in the cells’ DNA, thus leading to uncontrollable division of the cells. When this occurs, a cell can become cancerous – causing the formation of growths known as tumors. Tumors can cause a wide range of symptoms and health problems once they start to develop in the body.

Yet, not all tumors are cancerous. Benign tumors are noncancerous and they do not spread to nearby body tissue and organs. They can cause a few health problems if they begin to grow and press on neighboring tissue or organs. Malignant tumors, on the other hand, are cancerous and they can spread to nearby body tissue and organs. Depending on the type of cancer and its stage, different treatment options are available – each with its own objective.

References

http://www.startribune.com/mayo-u-develop-robocop-stem-cells-to-fight-cancer/441090583/

http://www.mayoclinic.org/diseases-conditions/cancer/basics/definition/con-20032378

http://www.healthline.com/health/cancer