CYCS and cancer: The process starts with the entry of the water-soluble mitochondrial protein cytochrome c (cytC, haemoproteid with molecular mass 12.4 kg/mol, 3 nm size, 104 amino acid residues, and one c-type haem-group) into the cytoplasm [1,2]; however, this does not occur in cancer cells because of their anaerobic utilization of glucose (instead of the mitochondrial oxygen metabolism that occurs in normal cells) [3,4,5].