Tumor ligands for Natural cytotoxicity triggering receptor 1 (NKp46-L)

Tumor ligands for NKp46 (Natural cytotoxicity triggering receptor 1) are a diverse group of molecules expressed on the surface of or secreted by cancer cells that serve as recognition signals for Natural Killer (NK) cells (Gaudieri et al., 2019). For many years, the identity of these ligands remained elusive, but recent research has identified several key proteins, most notably Platelet-derived growth factor DD (PDGF-DD), cell-surface Vimentin, and externalized Calreticulin (Feng et al., 2022; Huang et al., 2022). These ligands bind to the NKp46 receptor, triggering NK cell activation, degranulation, and the release of pro-inflammatory cytokines such as interferon-gamma (IFN-γ). In the tumor microenvironment, the expression of these ligands is often downregulated or masked as a mechanism of immune evasion, making their restoration or the use of synthetic mimetics a significant area of interest in cancer immunotherapy (Gaudieri et al., 2019). While most current clinical-stage drugs, such as NK cell engagers (e.g., SAR443579), target the NKp46 receptor itself to bypass the need for natural ligands, these tumor-derived molecules remain critical biomarkers for predicting NK cell-mediated anti-tumor responses (Innate Pharma, 2023). Understanding the interaction between NKp46 and its tumor ligands is essential for developing next-generation immunotherapies that can overcome tumor immune evasion mechanisms.

Other names

NCR1 ligandsNKp46 ligandsTumor-derived NKp46 ligandsPDGF-DDVimentinCalreticulinComplement factor H-related protein 1

Binding and activation of the NKp46 (NCR1) receptor on Natural Killer cells, leading to tumor cell lysis and IFN-gamma secretion.