CAR T-cell Therapy: Expanding Horizon of Oncology Treatment
Healthcare | Mar, 2022
Cancer is one of the leading causes of death
worldwide. In 2020, around 10 million people lost their lives to cancer, and
the number is expected to rise to 29.5 million by 2040. Over the years, many
conventional treatment approaches have been developed for cancer like
chemotherapy, bone marrow transplant, radiation therapy, surgery, and more such
interventions. However, their limited effectiveness with the heterogeneity of
cancer cells has led to a more improved therapeutic approach that enhances the
patient’s immune system to attack cancer cells without causing major side
effects. Chimeric Antigen Receptor-T cell (CAR-T) therapy has emerged as one of
the most promising treatments for cancer patients, which has shown effective
and durable clinical responses in recent years. The cell gene therapies support
the patient’s immune system and facilitate the elimination of cancer cells from
the body.
How does CAR T-cell Therapy Work?
CAR-T cell gene therapy is a kind of
immunotherapy that involves genetically engineered T-cells to strengthen the
immune system for fighting against diseases. T-cells are either taken from
patients or donors and are then modified in a laboratory to provide them the power
to recognize and kill cancer cells. When T-cells are infused into the patient,
the cells multiply and stay in the body as “living drugs,” which multiply into
hundreds of millions in the patient’s body to target the cancer cells that
harbor the foreign antigen on their surfaces. CAR T-cells may help eradicate
all the cancer cells and live in the body for months after infusion. This
immunotherapy treatment is used for treating acute lymphocytic leukemia (ALL)
in kids and young adults. Many clinical trials are underway to determine its
efficacy against different kinds of cancers.
CAR T-cell therapy leverages the natural
ability of the body to target and destroy malignant cells. CARs are genetically
engineered surface receptors designed to recognize tumor cells as dangerous and
bind to antigens found on them. When the extracellular domain binds to a tumor
antigen, the CAR is activated, which generates a cytotoxic response and
destroys the tumor cells. The CAR extracellular domain consists of
tumor-specific monoclonal antibodies, and the intracellular portion consists of
the signaling portion of the receptor. Full activation of endogenous T cells
requires two signals, one from intracellular signaling and the second from a
co-stimulatory domain, and then the CARs work to replicate both. Then, the
chimeric CAR molecule integrates the specificity of a monoclonal antibody with
the cytotoxic and memory capabilities of endogenous T cells to destroy the
cancer cells into the patient’s body.
