LY6K and esophageal squamous cell carcinoma: The four CR cases who continued the vaccination experienced long consistent CR for more than 2 years.(Iinuma et al. 2014)Another phase I trial for nine patients with advanced ESCC was carried out for patients with HLA-A*2402 using epitope peptides derived from novel cancer–testis antigens, LY6K and TTK, in combination with CpG-7909.