FIS1 and thyroid tumor: By western blot analysis, we detected, in the oncocytic cell line, the same trend of expression pattern of "mitochondria-shaping" proteins, as we observed in oncocytic thyroid tumors, i.e. an increase in the mitochondrial fission proteins Drp1 (p<0.05) and Fis1 (although not statistically significant) in XTC.UC1 cell line in comparison with TPC1 cell line (Fig 3A and 3B).