sentences:  Chromophobe renal carcinoma and hybrid oncocytic tumors with features of chromophobe renal carcinoma and renal oncocytoma, which are the most common renal tumor histologic subtypes associated with BHD, contain large numbers of mitochondria.Comparative gene expression profiling of BHD-associated renal tumors and sporadic counterpart tumors revealed distinct gene expression patterns and cytogenetic differences between the groups.BHD-associated tumors displayed high expression of mitochondrial- and oxidative phosphorylation-associated genes reflecting deregulation of the peroxisome proliferator-activated receptor gamma coactivator 1-alpha / mitochondrial transcription factor A (PGC-1α/TFAM) signaling axis.