The tumor-associated antigens targeted so far by vaccines for GC patients are melanoma-associated antigen (MAGE) A3 [116,117], HER2(p369) peptide [116], gastrin-17 diphtheria toxoid (G17DT) [118,119], URLC10 or VEGFR1 epitopes [120] and heat shock protein gp96 [121]; adjuvant BCG (Bacillus Calmette–Guérin) was also tested with chemotherapy [122] (Table 5). This evidence concerns the gene LY6K and gastric cancer.