FLCN and kidney cancer: These results are consistent with our previous report that Flcn deficiency caused upregulation of Pgc1α, a master regulator for mitochondrial biogenesis, resulting in increased mitochondria mass, oxidative phosphorylation, and ATP production in striated muscle, heart, and kidney cancer cell lines.15, 16 As we have shown in Fig. 3H–K, Pgc1α and Pgc1β expression is regulated by Tfe3.