Tumor-rejection antigen P1A (P1A)

Tumor-rejection antigen P1A (P1A) is a prototypical cancer-testis antigen (CTA) first identified in the murine P815 mastocytoma model. It is encoded by the Trap1 gene (distinct from the human TRAP1 heat shock protein) and was the first unmutated tumor antigen shown to be recognized by cytotoxic T lymphocytes (CTLs). P1A expression is typically restricted to the testis and placenta in healthy tissues but is frequently upregulated in various tumors, making it a highly specific target for immunotherapy. In preclinical research, P1A serves as a critical model for studying the efficacy of cancer vaccines, adoptive T-cell therapies, and the mechanisms of tumor immune escape. Therapeutic strategies targeting P1A include DNA vaccines, viral vector-based vaccines (e.g., ChAdOx1/MVA-P1A), and TCR-engineered T cells, often in combination with checkpoint inhibitors or epigenetic modifiers like decitabine to enhance antigen presentation.

Other names

Trap1P815AP815BCancer-testis antigen P1ATumor rejection antigen P1A

Induction of antigen-specific cytotoxic T lymphocyte (CTL) response; Epigenetic induction of antigen expression