PDK4 and cancer: DCA is known to inhibit all PDK isoforms at the mM range in vitro, with potency estimated to be higher against PDK2 < PDK 1 ≃ PDK4 < PDK3,36 and it has been shown that DCA treatment diminishes the phosphorylation of the three serine phosphorylation sites on PDH (PDHS232, PDHS293, and PDHS300) in different cancer cell lines.