Mitochondrial Dysfunction in Cross-resistance of Clinically Relevant Radioresistant Cells to X-rays and Docetaxe

Yoshikazu Kuwaharaa, Kazuo

Abstract

To determine whether mitochondria are involved in cross-resistance to docetaxel and X-rays in radioresistant cancer cells, ρ0 cell lines were established. As with radioresistant cells, a reduction in mitochondrial membrane potential in ρ0 cell lines compared with the corresponding ρ+ cell lines was confirmed. As expected, ρ0 cells were resistant to single-dose X-rays and docetaxel, as compared with the corresponding ρ+ cells. However, at 2 Gy/ day, all ρ0 cells died out after exposure to fractionated X-rays. Therefore, mitochondria may not be involved in the radioresistance of cancer cells against fractionated radiation therapy.