CD8A and neoplasm: In a spontaneous mouse model of melanoma, while tumor cell dissemination was an early event in progression of primary tumor, the development of overt metastases in the lung was postponed due to dormant DTCs, and metastases in lung were more rapid in CD8-depleted mice, which indicated that reduced proliferation or dormant maintenance of DTCs needed the involvement of cytostatic CD8+ T cells (20).