PDK4 and cancer: PDK exists in four isoforms that display unique tissue distribution and enzymatic activities, suggesting a different role depending on the cell type.28 Abnormal PDK activity has been previously associated with diabetes, metabolic disorders, cardiomyopathy, and several cancers.8 We have found that in human atherosclerosis, PDK1 and PDK4 expression positively correlates with pro-inflammatory markers related to CD4+ T-cells and macrophage activation.