CD8A and neoplasm: The data supported that tumors early developed an immunosuppressive microenvironment, as evidenced on the basis of various findings; (a) strongly reduced CD8+ T effector/Treg ratio compared to normal lung; (b) expansion of CD39hiCD38hiPD-1hiCTLA4hiFoxp3hi Tregs at the tumor site; (c) strong reduction in the tumor microenvironment of CD16+NKcells, with reduced content of granzyme B; (d) depletion of CD141+ dendritic cells and enrichment in PPARγhi macrophages; (e) reduction of CD16+ monocytes, but not of CD14+ monocytes at the tumor site [302].