March 11, 2022 | LIFE | By Gabriella Casagrande
Melanoma is a type of skin cancer, and although it is rare, it is the most aggressive and thus the most dangerous type.
The top outer layer of skin, the epidermis, is made up of squamous, basal, and melanocyte cells. Melanocytes produce melanin, the pigment that gives skin color and protects skin from ultraviolet radiation damage. At a certain level of UV radiation, melanocyte DNA is harmed beyond repair. This damage causes mutations in the DNA that result in uncontrolled cellular growth, leading to cancer. If the damage is not caught quickly, these cancerous cells can travel throughout the body, leading to advanced melanoma in other organs.
Depending on the stage of cancer, melanoma can be treated surgically, by immunotherapy, targeted therapy, chemotherapy, or radiation therapy. Each of these has adverse side effects and may leave behind undetected cancerous cells.
The new skin cancer vaccine was synthesized using a biodegradable polymer. Polymers are large molecules that are made up of smaller subunits that can be natural, such as DNA, or synthetic, such as polyester. Within these tiny particles of biodegradable polymer, the researchers injected small chains of amino acids, the building blocks of proteins, that are expressed in cancerous melanoma cells. This is their nano-vaccine, a principle that is based on tiny particles sending pathogenic-like signals to immune cells to stimulate a response.
This nano-vaccine has proven effective at both preventing and treating melanoma. Mouse subjects injected with the vaccine and then with melanoma did not develop cancer. Mice with melanoma that were treated with the nano-vaccine alongside established immunotherapy showed a slower than average disease progression and a longer than expected lifetime.
The vaccine can expand the sensitivity of T-effector cells, which direct an immune response, in a host body. Thus, the host body is less overcome by cancerous cells as it’s antigen internalization, processing, and long-term recognition is improved.
These findings have huge implications in both research, where it is a strong foundation for nano-vaccine and combination therapies, and medicine, because it can potentially be expanded upon to treat other cancers.