PPARD and B-cell chronic lymphocytic leukemia: A similar phenomenon has been found in chronic lymphocytic leukemia (CLL) cells: glucocorticoids or synthetic PPARβ/δ agonists are upregulated in depleted tissue culture media (low glucose levels, hypoxia, and exposure to cytotoxic drugs), protecting CLL cells from metabolic stressors (Li et al., 2017).