The tumor microenvironment is an ecosystem of immune cells, signaling molecules, extracellular matrix, and mechanical cues that can support the growth of the tumor, protect it from the patient’s immune system, encourage resistance to therapy, and promote metastases.
 

The Cancer Vaccine Institute is developing strategies that modify the tumor microenvironment to allow the immune system to recognize tumor cells as dangerous and result in their elimination. 

We are actively evaluating multiple immunomodulatory approaches that could be used alone or in combination with vaccines and T-cell therapies to reconfigure the tumor immune environment and stimulate an effective anti-tumor immune response. These strategies include activating antigen presenting cells by stimulating toll-like receptors (TLRs) and eliminating immune suppressive cell populations (Tregs and MDSC), which lead to shifting the microenvironment to one that supports tumor cell killing by cytotoxic T lymphocytes.
 

One of CVI’s most active areas of research aims to understand how the makeup of the bacteria in our gut, known as the gut microbiome, can influence how patients respond to vaccines and immune therapies. With that information, we’re developing precision probiotics to increase the efficacy of those therapies. 
 

In this effort, we made a novel discovery. Immune cells that protect the gut microbiome from immune attack may also recognize antigens found on tumor cells. As a result, these immune cells also incidentally protect tumor cells from being recognized and destroyed by the immune system. We are developing precision probiotics that help modify the tumor microenvironment from one that suppresses anti-tumor immune responses to one that supports anti-tumor immune responses. This allows for vaccines and other immune therapies the opportunity to be more effective.