Stimulant Injections Transform Tumors into “Cancer Vaccine Factories”

Scientists out of the Icahn School of Medicine at Mount Sinai hospital, in New York, have recently revealed an exciting breakthrough in cancer research.  Apparently they have developed a new treatment that can supercharge the body’s immune system in a way that it will identify and destroy tumor cells, naturally and automatically. 

This technique is just part of a still emerging arm of cancer treatment you may know as immunotherapy.  This field, essentially, uses the body’s own natural defenses to better fight against particularly persistent conditions like cancer. There are a couple ways to engage immunotherapy.  For one, scientists can harvest T-cells from a patient’s immune system and engineer them, in a lab, to more effectively recognize and engage with predatory cancer cells.  This is known as adoptive immunotherapy.  In addition, scientists can treat the same T-cells with drugs that disable proteins that would normally neutralize attacks. This is known as checkpoint blockade immunotherapy. 

This new method, however, involves injecting very-carefully selected immune stimulants directly into the tumor site in order to slow down and reduce the presence of cancerous cells in the body.  One of the stimulants injected can recruit immune cells—known as dendritic cells—who essentially become new soldiers in the immune system’s proverbial army.  Another stimulant, then, instructs these dendritic cells to be commanders of this quickly growing army. 

The two troops in this army, then, collaborate to train the immune system to be better at recognizing a tumor cell. Upon recognizing the tumor cell, then, the newly-empowered immune system can be more active at hunting down similarly cancerous cells (tumors) throughout the body and, more importantly, killing them. 

The researchers describe this method as “In situ vaccination” and comment that it is quite effective at transforming the tumor into a cancer vaccine factory instead of one for cancerous cells.  So far it has proved quite effective in lab mice and has been tested on at least 11 patients with advanced stage lymphoma. While only some experienced full remission (for as little as a few months to many years), the results are quite promising. 

Lead study author Joshua Brody explains, “The in situ vaccine approach has broad implications for multiple types of cancer. This method could also increase the success of other immunotherapies such as checkpoint blockade.” 

The results of this study have been published in the journal Nature Medicine.