Tumor protein p53 peptide epitope (TP53 peptide epitope)

The Tumor protein p53 (TP53) peptide epitope is a specific amino acid sequence derived from the p53 protein that is presented on the cell surface by Human Leukocyte Antigen (HLA) molecules (Hsiue et al., Science 2021). In many malignancies, TP53 undergoes missense mutations, resulting in the presentation of mutant "neoantigens" that are absent in healthy tissues (Lo et al., JCI 2020). These epitopes, particularly common "hotspot" mutations like R175H, R273H, and R248W, serve as precise targets for advanced immunotherapies (Malekzadeh et al., Nature Communications 2019). Therapeutic modalities targeting these epitopes include T-cell receptor (TCR) engineered T-cells and bispecific antibodies designed to recognize the peptide-HLA complex with high affinity (Hsiue et al., Science 2021). By engaging the immune system against these specific markers, these drugs aim to selectively eliminate cancer cells while minimizing damage to normal cells expressing wild-type p53. However, the clinical application of these therapies is restricted by the patient's HLA genotype, as the epitope must be presented by a compatible HLA molecule, such as HLA-A*02:01 (Lo et al., JCI 2020). Additionally, tumors may develop resistance through the loss of HLA expression or mutations in the antigen processing machinery (Vogelstein et al., Science 2013). Despite these challenges, the TP53 peptide epitope remains one of the most promising targets for broad-spectrum, mutation-specific cancer immunotherapy.

Other names

p53 neoantigenp53-derived peptidep53-HLA complexMutant p53 epitopep53 peptide-MHC

Therapeutic agents targeting the TP53 peptide epitope, such as TCR-engineered T-cells or bispecific T-cell engagers, operate by binding specifically to the mutant p53 peptide presented within the groove of an HLA molecule on the tumor cell surface (Hsiue et al., Science 2021). This binding event facilitates the recruitment and activation of cytotoxic T-lymphocytes, leading to the formation of an immunological synapse and the subsequent release of cytotoxic granules like perforin and granzymes (Lo et al., JCI 2020). The resulting targeted lysis of the tumor cell is highly specific to the mutation, sparing healthy cells that do not present the neoantigen (Malekzadeh et al., Nature Communications 2019).