Kita-Kyushu lung cancer antigen 1-derived peptide presented by Human Leukocyte Antigen (KK-LC-1/HLA)

Kita-Kyushu lung cancer antigen 1 (KK-LC-1), also known as Cancer/testis antigen 83 (CT83), is a protein that is highly expressed in various epithelial cancers but has restricted expression in normal tissues, primarily limited to the testis. Because germ cells in the testis do not express Human Leukocyte Antigen (HLA) Class I molecules, the KK-LC-1-derived peptides presented by HLA on tumor cells serve as highly specific targets for immunotherapy. The most well-characterized epitope is the KK-LC-1(52–60) peptide (RQKRILVNL) presented by HLA-A*01:01. This peptide-MHC complex is a primary target for T-cell receptor (TCR) engineered T-cell therapies currently in clinical development. By targeting this specific complex, therapies aim to induce a potent and selective anti-tumor immune response while minimizing damage to healthy somatic tissues.

Other names

KK-LC-1 peptide-MHC complexCancer/testis antigen 83 (CT83) peptideKita-Kyushu lung cancer antigen 1 (KK-LC-1)CT83/HLA complex

Therapeutic agents, such as T-cell receptor (TCR) engineered T-cells, specifically recognize and bind to the KK-LC-1 peptide fragment presented by HLA molecules on the surface of tumor cells. This binding triggers T-cell activation, leading to the release of cytotoxic granules (perforin and granzymes) and cytokines, which results in the selective lysis of the cancer cells expressing the antigen.