The Promising Future of Gene Therapy and Lymphoma
Non-Hodgkin lymphoma affects over 700,000 people in America alone. Though current treatments are moderately effective, especially for aggressive forms of the disease, more can be done to help people impacted by NHL. Researchers are doing just that by working to develop new, innovative treatment for the condition. Many of these new methods are developed based off of scientific innovations that researchers then translate into cancer care. In addition to enhancing existing treatments such as stem cell transplants, these advances in general scientific knowledge have allowed researchers to attempt completely novel, “next-generation” forms of cancer treatment. One such treatment developed from the field of genetic engineering is gene therapy.
Genetic Engineering
Genetic engineering is the process of changing the DNA of an organism’s genome. Scientists use genetic engineering to alter specific traits of an organism. The technology is used towards diagnosing diseases, treating diseases, enhancing the ability of organisms, and in other fashions.
In 2003, researchers at the National Institutes of Health (NIH) successfully completed the Human Genome Project. The project resulted in a sample sequence of human DNA to be used for biomedical projects, and opened the door for many of the discoveries made in genomics and genetic engineering today.
According to the NIH, almost “every human ailment has some basis in our genes.” Thus, the implications of genetic engineering and genomic research are enormous for developments related to better diagnosing and treating a myriad of diseases. With today’s resources, especially the sequencing from the Human Genome Project, sciences have the ability to study more of these conditions than ever before.
What is Gene Therapy?
Gene therapy is the process of altering the DNA of cells to achieve a desired outcome. It is closely related to genetic engineering in that both methods involve changing the DNA of a specific target. However, genetic engineering refers to this process in broader terms (usually to enhance something beyond its “normal” capabilities), while gene therapy is genetic engineering specifically for the treatment of a disease or a positive health related outcome.
How Are Researchers Applying Gene Therapy?
Researchers have been studying how to apply genetic engineering in ways that help people with various disease for decades. Though there’s still a long way to go, there are multiple cases of people being successfully treated with gene therapy techniques. One example is the immune deficiency disease Adenosine deaminase deficiency (ADA). In the trials for ADA gene therapy, blood stem cells were removed from a patient’s body, then modified to repair the defective genes before being reinserted to the patient’s body. The newly edited cells improved function so much that many of the patients could cease regular injections typically needed to treat ADA. Gene therapy has also been proven to improve conditions for, though not treat, things such as hereditary blindness and hemophilia.
Gene Therapy and Cancer
Gene therapy treatments are underway for multiple types of cancer. One is melanoma, a common type of skin cancer. Interestingly, researchers are using the herpes simplex 1 virus, which usually causes cold sores, to treat melanoma. This is possible by modifying the virus to act differently once it enters a patient’s body. Once the virus has been modified, not only does it kill cancer cells (and no longer cause cold sores), but it has the ability to train other cells already within a patient’s body to do the same. Trials have also been successfully conducted for gene therapy treatment of leukemia. Unlike the virus used in the melanoma trials, the method used to treat leukemia more closely resembles the process of a stem cell transplant. Cells are removed from a patient’s body, genetically engineered to fight leukemia, and then reinserted into the patient’s body after the modification is complete.
Gene Therapy and NHL Treatment
In addition to melanoma and leukemia, researchers are also making strides on using gene therapy to treat non-Hodgkin lymphoma. Researchers are currently investigating a treatment referred to as CAR-T, short for chimeric antigen receptor T-cell therapy. Similar to the leukemia gene therapy treatment, cells are removed from the patient’s body, modified, and reinserted. For NHL patients, immune cells are removed from the body to be “reprogrammed.”
So far, results with CAR-T have been very positive. In one recent trial, over 80% of the 101 patients who received CAR-T were still alive six months post-treatment. This is especially impressive when you take into account that the people who undergo CAR-T did not have a good prognosis previously. In this case, the participants were patients who had a one in ten chance of complete remission, according to an oncologist with experience with the treatment.
Gene Therapy and NHL: A Success Story
Dimas Padilla is one of the patients whose life was changed by the chance to test gene therapy as a last effort to cure his cancer. Padilla had already tried standard chemotherapy, and later a bone marrow transplant, to rid his body of his non-Hodgkin lymphoma. But, both times the cancer returned. When Padilla first began CAR-T treatment, his cancer was so severe that his lymph nodes were swollen to the point that they were pressing on his vocal chords, taking away his ability to speak for almost three months. Amazingly, just a few days after the modified cells were inserted into his body, the swelling in his lymph nodes began to decrease. The treatment was such a success that Padilla is now happily in remission.
But, physicians and patients who have received the treatment warn that it is not an easy ride. That’s partially why, right now, gene therapy is reserved for NHL patients for whom standard cancer treatment has been unsuccessful. Similar to a bone marrow transplant, the patient’s immune system must be weakened in order to successfully transmit the modified cells. Patients undergo intense chemotherapy to get their immune systems to that point, and it can be extremely tough on the body. Even Padilla, a success story for CAR-T, experienced fevers, shaking, and even memory loss. Still, for patients like Padilla the side effects are a small price to pay for the huge positive impact the treatment has made on his quality of life.
Clinical Trials
Though researchers are starting to see successes and are confident about the future of gene therapy for treating NHL, treatments are all still in the clinical trial phase. In fact, ciloleucel, the drug used in the CAR-T treatment, is the first component of CAR-T to even make it to the FDA approval stage (it is still in the process of being approved).
Clinical trials are necessary to make sure any new medications or treatments offered to the general public are safe. However, they can be a slow process, and thus at times slow down the progression of disease treatment. If you’re interested in clinical trials, you can always ask your physician about any new treatments or products in the works. You can also find out more about cancer clinical trials here.
Other Developments
Though certainly an exciting one, gene therapy isn’t the only new method of treating NHL on the horizon. Another gene-related advancement resulted from the studying of the DNA of cancer cells to improve diagnostic tests. Since there are many different types of NHL, and the specific variation one highly influences treatment choices, this is huge in terms of successfully treating more NHL patients.
In addition to modifying immune cells, some researchers are working on modifying virus cells to deliver chemotherapy drugs to the patient. This novel treatment would spare patients from having to go through the severe weakening of the immune system currently caused by general chemotherapy. Reducing the negative side effects of chemotherapy would take some weight off of the heavy burden already put on cancer patients, not to mention the potential for improved treatment outcomes.
Though these treatments are still in the early stages, there’s a lot to look forward to in terms of better treating people with cancer. With time, current methods, and outcomes, will only improve.
References
https://ghr.nlm.nih.gov/primer/therapy/genetherapy
https://www.yourgenome.org/facts/what-is-genetic-engineering
https://www.genome.gov/18016863/a-brief-guide-to-genomics/
http://ethics.missouri.edu/gene-therapy.html
http://learn.genetics.utah.edu/content/genetherapy/success/
https://www.cancer.gov/about-cancer/treatment/research/car-t-cells
https://www.cancer.org/treatment/treatments-and-side-effects/clinical-trials.html
https://www.cancer.org/cancer/non-hodgkin-lymphoma/about/new-research.html
