For decades, cancer has challenged medicine’s best strategies. Surgery, chemotherapy, and radiation have saved countless lives, yet for many patients, cancer’s persistence reveals the limits of these traditional treatments. A revolution began when scientists realized that the immune system, our natural defense against disease could be reprogrammed to recognize and destroy cancer. Among the most groundbreaking advances in this field is CAR T-cell therapy, a method that turns a patient’s own immune cells into precision cancer-fighting machines.
What Are CAR T Cells?
CAR T stands for Chimeric Antigen Receptor T cells. It is a form of cellular immunotherapy, involving genetic engineering T cells, giving them new maglinant cell recognition powers.
T cells are natural killer cells, a type of white blood cell that fights infection or abnormal cells. However, in many cancers, maglinant cells find ways to hide from these T cells, disguising themselves or suppressing immune responses.
How It Works?
The process begins by collecting T cells from the patient’s blood. These immune cells are then genetically engineered in the laboratory to produce special proteins on their surface called chimeric antigen receptors (CARs). These synthetic receptors enable the T cells to recognize and bind to specific proteins found on cancer cells.
Once modified, the CAR T cells are multiplied into millions of copies and then infused back into the patient. These expanded cells make up the final CAR T-cell therapy product—a living drug, capable of patrolling the body, identifying their target antigens, and destroying cancer cells with remarkable precision.
From the initial blood collection to the reinfusion of engineered cells, the entire process typically takes about 3 to 5 weeks.
Transformative Successes in Blood Cancers and Beyond
The first CAR T-cell therapies approved by the FDA, Kymriah (tisagenlecleucel) and Yescarta (axicabtagene ciloleucel), have achieved remarkable success in treating certain blood cancers such as acute lymphoblastic leukemia (ALL) and diffuse large B-cell lymphoma (DLBCL).
For patients who had no remaining treatment options, these therapies brought long-lasting remissions. In some studies, more than 80 percent of children and young adults with relapsed ALL went into remission after CAR T-cell treatment.
These results proved that reprogramming a patient’s own immune system could effectively eliminate cancers once thought incurable.
A New Frontier: CAR T Therapy for Glioblastoma
Researchers are now investigating whether CAR T cells can also target solid tumors, which are far more challenging to treat. One of the most promising advances comes from a recent study at Massachusetts General Hospital (MGH) that tested CAR T therapy for glioblastoma, an aggressive and often fatal form of brain cancer.
Glioblastoma is notoriously difficult to treat because of its location within the brain, which limits surgical and therapeutic access, and because it is a heterogeneous tumour, its cancer cells are not all alike and therefore do not respond uniformly to a single treatment strategy. As a result, the risk of recurrence remains extremely high.
In this small early trial, Dr. Marcela Maus, Director of the Cellular Immunotherapy Program at the Mass General Cancer Center, and her team developed a new version of CAR T therapy called CAR-TEAM to tackle glioblastoma. These engineered T cells were designed to target EGFRvIII, a mutation found on many tumor cells, and to also attack wild-type EGFR, a protein present on most glioblastoma cells but not in normal brain tissue. The CAR-TEAM cells were injected directly into the patient’s brain, allowing them to reach and destroy a wider range of tumor cells while avoiding healthy cells.
The patient outcomes were remarkable: one patient experienced rapid but temporary tumor regression, with cancer markers in blood and cerebrospinal fluid dropping to undetectable levels. Another patient’s tumor shrank 18.5 percent within two days and 60.7 percent by day 69, with the response lasting over six months. A third patient showed near-complete tumor regression just five days after treatment.
These results, though early, provide the first clear evidence that CAR T therapy can reach and attack brain tumor cells effectively, offering hope for one of the most challenging solid tumors. Researchers are now exploring ways to make these responses last longer, such as multiple doses or enhancing the survival of T cells inside the tumor.
This early success in glioblastoma offers a glimpse of what may come—the possibility that CAR T therapy could one day work against some of the most stubborn and deadly solid tumors.
The Future of CAR T: Beyond Cancer
The principles of CAR T-cell engineering are beginning to extend beyond oncology. Researchers are exploring applications for autoimmune diseases, such as lupus, where modified immune cells could selectively eliminate harmful immune components. There are also early-stage studies investigating CAR T-cell therapies against viral infections, including HIV.
This expansion signals a broader shift: CAR T is not just a cancer therapy. It’s a platform for reprogramming the immune system itself.
Scientect 