Provided herein are methods of treating an IDH mutant cancer in a subject comprising administering to the subject a therapeutically effective amount of a composition comprising an all-trans retinoic acid (ATRA). In some embodiments, the methods increase an NK-cell-mediated immune response and/or a T cell-mediated immune response to the cancer. In some embodiments, the cancer is a glioma or a chondrosarcoma. In some embodiments, the expression of one or more NKG2D ligands (e.g., ULBP1 and ULBP3) is increased in a tumor microenvironment of the cancer. In some embodiments, CCL2 production, the number of NK cells, and/or apoptosis of tumor cells is increased in a tumor microenvironment of the cancer. In some embodiments, the subject has an IDH1 mutation at arginine 132 or an IDH2 mutation at arginine 172. In some embodiments, method reduces growth of a tumor.