CD8A and neoplasm: There are reasons for the lesser success of many clinical results of cancer vaccines, including (1) a lesser amount of efficient tumor antigens [13]; (2) a lack of enhanced adjuvant subcomponents for stimulating a significant immune response to combat tumor cells [14]; (3) long peptides have a less efficient presentation of antigens, which limits detection by CD8 + T cells [15]; and (4) much of the microenvironment of tumors inhibits the immune response, suppressing the activity of T cells to kill the tumors [16].