However, the major disadvantages of peptide-loading DC vaccines are related to the following factors: (1) the limited number of available immunogenic peptides specific for tumors [13]; (2) monoclonal peptide-specific CD8+ CTLs may not be sufficiently effective to treat cancer patients [14]; and (3) MHC class I molecules and certain TAAs are significantly downregulated in tumors during tumor progression [14]. The gene discussed is CD8A; the disease is neoplasm.