Wi 38 cells

The HeLa and SAS human cancer cell lines were obtained from the Cell Resource Center for Biomedical Research, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan. HeLa and SAS ρ⁰ cells were established by culturing cells with 50 ng/mL ethidium bromide as described previously [13 (link)]. Cells were cultured in RPMI 1640 (189–02025; Fujifilm Wako Pure Chemical Corporation, Osaka, Japan) with 10% FBS (Biological Industries, Cromwell, CT, USA), 110 μg/mL pyruvate (Sigma-Aldrich, St Louis, MO, USA), and 50 μg/mL uridine (TOKYO Chemical Industry Co. Ltd, Tokyo, Japan) in a humidified atmosphere at 37 °C with 5% CO₂. Mitochondria were isolated from WI-38 cells (RIKEN BRC, Ibaraki Japan) using a mitochondrial isolation kit (ab110171, Abcam, Cambridge, UK) for 24 h, as described previously [30 (link)]. Then, transferred-mitochondria (Mito) cells were established by culture with 5 μg/mL isolated mitochondria. HeLa and SAS parental cells and Mito cells were cultured with RPMI 1640 with 10% FBS in a humidified atmosphere at 37 °C with 5% CO₂. Exponentially growing cells were used in all experiments.