CD8A and neoplasm: The overall response to ICIs is reportedly unsatisfactory for many types of cancer [6], highlighting the need to combine ICIs with cancer immunotherapeutic approaches, such as therapeutic cancer vaccines, with the artificial generation, stimulation, and tumor microenvironment (TME) infiltration of cancer-specific CD8+ T cells called cytotoxic T lymphocytes (CTLs) [2,7,8,9].