CD8A and melanoma: Depletion of MDSCs using ATRA in patients with small-cell lung cancer, dramatically enhanced the efficiency of a DC vaccine against p53 by increasing the levels of CD8+ T cells.648 In a phase I/II study, ATRA was demonstrated to significantly decrease the immunosuppressive function of MDSCs and increase the levels of CD8+ T cells in patients with melanoma receiving ipilimumab therapy compared with patients receiving ipilimumab alone.649