Many studies have found that dendritic cell (DC)- and tumor-derived exosomes express a large number of major histocompatibility complex class I molecules (MHC I) and tumor markers such as heat shock proteins (HSP), which are involved in antigen presentation and stimulation of T cells and have been shown to trigger CD8+ T cell-dependent anti-tumor responses in vitro and in vivo [25]. This evidence concerns the gene CD8A and neoplasm.