Researchers at The University of Texas MD Anderson Cancer Center have developed a nanotechnology platform that can make cancer cells more vulnerable to immune attack in the body. The researchers call their system the bispecific tumor-transforming nanoconjugate (BiTN) platform.
The idea is to make solid tumors more attractive to the immune system by attaching a molecule that acts as an “eat me” signal to white blood cells. This molecule is called the signaling lymphocytic activation molecule family member 7 (SLAMF7) receptor and is more often found on cancer cells in blood cancers, which explains the relative success of current immunotherapy in these cancer types. Solid tumors are usually less susceptible to the immune system, so these researchers decided to make them more attractive by attaching SLAMF7 to their surface.
Immunotherapies have revolutionized the treatment of many cancers. There is something satisfying about mobilizing our own immune system to attack cancer, and it may obviate the need to administer large doses of toxic cancer drugs that can have a wide range of unacceptable side effects. Our immune cells can be very effective at sniffing out and destroying cancer cells, but in some cases they may need a little help identifying the tumor.
In the case of blood cancers, such as leukemia and lymphoma, immunotherapies are often relatively successful. In part, this is because these cancers tend to express SLAMF7 on their cell surface, and this is key for the immune system to identify them as worthy of attack and acts as sweet honey for phagocytic white blood cells. In solid tumors, however, the efficacy of immunotherapies tends to be more mixed and needs to be improved.
These researchers have developed a nanotechnology system that can label solid tumor cells with SLAMF7, making them far more palatable than white blood cells. The system is called the bispecific tumor-transforming nanoconjugate (BiTN) platform and consists of a tumor-specific antibody conjugated to SLAMF7.
So far, researchers have attached SLAMF7 to a HER2-recognizing antibody to target HER2-positive breast cancer cells and showed that following this labeling, the cells were much more likely to be attacked and phagocytosed by immune cells. The nanotechnology platform can also be rapidly adapted to target other tumor types, simply by changing the targeting antibody present in the system.
“With this new platform, we now have a strategy to change a solid tumor, at least immunologically, to resemble a hematological tumor, which often has a much higher response rate to immunotherapy treatments,” said Wen Jiang, a researcher involved in the study. “If we can translate and validate this approach in the clinic, it could allow us to get closer to maximizing the effectiveness of immunotherapy drugs with cancers that have not traditionally responded well.”
Study in Nature Nanotechnology: Immunological transformation of solid tumors using a bispecific nanobioconjugate for cancer immunotherapy
Via: University of Texas MD Anderson Cancer Center