For example, tumor biopsies from patients with progressed melanoma and MAPK inhibitor resistance showed increased mitochondrial biogenesis and mitochondrial bioenergetics [62] and in primary metastatic colorectal cancer higher levels of the transcription factor TFAM, mtDNA copy numbers and ADP-triggered oxygen consumption rate (OCR) were found as compared to non-metastatic primary cells [63]. Here, TFAM is linked to melanoma.