Mitochondrial Activities of a Cell Line Derived from Thyroid Hürthle Cell Tumors

Objective: We conducted a study on the functional characteristics of mitochondria in an oxyphilic thyroid tumor cell line, which may provide useful clues about Hurthle cell tumors carcinogenesis. Design: The functional study on thyroid tumors with cell oxyphilia (Hurthle cell tumors), characterized by mitochondrial hyperplasia, was carried out in XTC.UC1, and B-CPAP, an oxyphilic and nonoxyphilic thyroid tumor cell line, respectively. Main outcome: XTC.UC1 cell line showed higher activity of mitochondrial respiratory complexes I and II and decreased activity of complex III. The increased activity of complex I was not matched by increased expression of complex I subunits. The XTC.UC1 cells relied mostly on oxidative phosphorylation for energy conservation, although their mitochondrial energetic function was less efficient when related to mitochondrial content of the cells. Finally, the oxyphilic cell line produced significantly higher amounts of reactive oxygen species (ROS) in comparison with B-CPAP cell ...