TP53 and neoplasm: For example, TP53, whose mutations present in half of BC, differs in several amino acids cross-species (Supplementary Fig. S3), and thus, xenogeneic TP53 peptides of xenogeneic cells could be recognized by the host T-cell receptor (TCR) repertoire and serve as a partial surrogate for spreading differential neoantigen immunogenicity, leading to “bystander activation” of anti-tumor activity.