One of the hot topics in medicine today is the idea of “personalized medicine” and tailoring medications and therapeutic approaches so that they specifically match individuals’ needs. Personalized medicine is oftentimes made possible by revolutionary advances in genetics and genetic engineering. This is also the case with new and emerging therapies for cancer. New approaches for treating cancer include T cell and dendritic cell therapy, which are two types of cells involved in the adaptive immune response. Scientists hope to utilize the memory and specificity capabilities of adaptive immunity to direct immune responses towards cancerous cells.
Dendritic cells are one of the target cell types that is currently being studied for potential cancer treatments. Dendritic cells are antigen presenting cells that are responsible for activating the B and T cells of the adaptive immune response. There are various different types of dendritic cells and one article published in Nature explored the potential of those dendritic cell types as targets for cancer treatments. The biggest problem with cancer is that self cells are growing uncontrollably, creating tumors, that have immunity to normal immune responses due to their presentation of “self-peptides” that do not activate T cells and B cells. The nature article discusses one specific dendritic cell type, cDC1s, that is related to mediating tumor cell immunity from the immune response. The article explains that cDC1s are specifically involved in cross-presenting MHC class I molecules of exogenous antigens to cytotoxic T cells, resulting in tumor rejection, meaning that tumor cells are targeted for destruction by cytotoxic T cells. The article goes into much greater depth as to how cDC1s are related to the immune response against cancer, however it is made clear that cDC1s are crucial in initiating that response and are extremely promising targets for genetic engineering in order to initiate specific responses to specific cancer types in the form of vaccines. Overall, scientists hope to identify and implement a method for modifying existing cDC1s in the patients immune system to present antigens from their own cancerous cells outside of the body. Then, the hope is to inject those cells in a vaccine form back into the patient, allowing the cell to migrate into secondary lymphoid organisms and initiate an effective adaptive immune response.
One of the other targets of novel cancer treatments is T cells. T cells have two different subtypes: helper T cells and cytotoxic T cells. Thus far, cytotoxic T cells have been the main target of cancer treatment projects as these are the cells that directly interact with target cells to induce apoptosis (programmed cell death). This treatment approach, called CAR T-cell therapy, involves removing existing T cells from a patient and modifying them in a lab such that they express chimeric antigen receptors (CAR). These receptors bind to specific antigens on the surface of cancerous tumor cells and kill them effectively. While it has shown some promising results and limited side effects (severe inflammation) in comparison to chemotherapy, CAR T-cell therapy’s main drawbacks are time and cost. According to the American Journal of Managed Care, CAR T-cell therapy can cost nearly $400,000 at the low end and can take as long as 3 weeks to manufacture the CAR T-cells for treatment. This type of therapy has mostly been limited to blood cancers (leukemia), however an article published by ScienceDaily presents evidence for applying CAR T-cell therapy to “solid cancers.” Researchers at Tel Aviv University recently identified a specific group of T helper cells that specifically target cancerous tumor cells coated with immunoglobulin G, an antibody. As a result of this discovery, researchers can now develop new CAR T-cell types that have high affinity and killing power for cells presenting high levels of IgG antibody on their surface. This is particularly important because the novel cells that were created using this process have shown experimental success and efficacy in fighting solid tumor cancers as well as leukemias and lymphomas.
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