Prostate-specific antigen and TRICOM costimulatory molecules (PSA-TRICOM)

Prostate-specific antigen (PSA) and the TRICOM triad of costimulatory molecules (B7-1, ICAM-1, and LFA-3) represent a multi-component immunotherapy target designed to enhance the immune system's ability to recognize and destroy prostate cancer cells (Madan et al., 2010, J Clin Oncol). PSA serves as the tumor-associated antigen, while the TRICOM molecules provide the necessary secondary signals to activate and sustain a robust T-cell response (Gulley et al., 2019, Expert Opin Biol Ther). This approach typically utilizes viral vectors, such as vaccinia or fowlpox, to deliver the genes for these proteins directly into host cells, leading to their surface expression (NCI Drug Dictionary). By presenting PSA in the context of these costimulatory signals, the therapy overcomes the immune tolerance often associated with cancer. The primary biological function of this target complex is the induction of a specific, long-lasting cellular immune response against cells expressing PSA. Clinically, this strategy has been primarily investigated for the treatment of metastatic castration-resistant prostate cancer (mCRPC) (Kantoff et al., 2010, J Clin Oncol). While PSA is a well-known biomarker for prostate cancer, its use as a vaccine target combined with TRICOM aims to convert it into a focal point for cytotoxic T-lymphocyte activity.

Other names

PROSTVACPROSTVAC-VFPSA-B7.1-ICAM-1-LFA-3rV-PSA-TRICOMrF-PSA-TRICOMPoxvirus-based PSA-TRICOM vaccine

Viral vector-mediated delivery of PSA and costimulatory molecules (B7-1, ICAM-1, LFA-3) to antigen-presenting cells to stimulate a PSA-specific T-cell immune response against prostate cancer cells.