Estrogen receptor 1 mutant neoepitope (ESR1 mutant neoepitope)

ESR1 mutant neoepitopes are short, mutated peptide fragments derived from constitutively activating mutations (such as Y537S, D538G, E380Q) in the estrogen receptor alpha (ESR1) gene, commonly found in endocrine therapy-resistant, ER-positive breast cancer[3][1]. These mutations confer ligand-independent activity to the receptor, promoting tumor growth and resistance to tamoxifen and aromatase inhibitors[3][6]. The resulting mutant peptides can be processed and presented by tumor cell MHC complexes, rendering them potential targets for immunotherapy, including T cell-mediated responses and cancer vaccine development[1][3][5]. In clinical and preclinical studies, ESR1 mutant neoepitopes demonstrate immunogenicity—i.e., the ability to elicit mutation-specific T cell responses—and are being explored as novel therapeutic targets for overcoming endocrine resistance in breast cancer[1][2][3].

Other names

ESR1 mutant peptideESR1 mutant epitopemutant estrogen receptor alphamutant ERαESR1mut neoepitope

Selective estrogen receptor degrader (SERD), downregulation of ER signaling; Immune targeting by T cells through presentation of neoepitopes (experimental cancer vaccines)