LY6K and esophageal squamous cell carcinoma: Clinical trials using a vaccine made up of multiple peptides, including TTK, lymphocyte antigen-6 complex locus K (LY6K), and insulin-like growth factor-II mRNA binding protein-3 (IMP3), showed that vaccination with multiple peptides was able to induce HLA-A*2402-dependent clinical responses in ESCC patients [79, 80].