PRCC and renal cell carcinoma: SREBP1, a master regulator of lipid synthesis (Horton, Goldstein, and Brown 2002), is upregulated in response to PRCC‐TFE3 expression and HIF1α activation, leading to increased expression of lipogenic enzymes (ACLY, ACACa, and FASN) and enhanced lipid accumulation in TFE3‐RCC cells and tissues.