PDK4 and cutaneous melanoma: Specifically, PDK4 was found to act as a protective factor in liver hepatocellular carcinoma (LIHC), kidney renal clear cell carcinoma (KIRC), low-grade glioma, and skin cutaneous melanoma, while acting as a risk factor in adrenocortical carcinoma and stomach adenocarcinoma (STAD) (Fig. 8A).