In the present study, findings from the differential expression analysis of the aggressive MTT cells compared to MPC guided our choice for the evaluation of key players in glycolysis and OXPHOS in human SDHB- and VHL-derived PHEOs/PGLs, as a first step in uncovering potential causes for increased tumor aggressiveness in SDHB-related tumors. This evidence concerns the gene SDHB and neoplasm.