Here, we reveal important novel mechanistic aspects of increased antioxidant capacity in cancer cells and demonstrate a therapeutic potential for SLC25A1 inhibition to overcome radioresistance in chronically Hx lung cancer cells: (i) Exposure of cancer cells to acute or chronic cycling severe hypoxia was associated with upregulated expression of the citrate transporter SLC25A1. The gene discussed is SLC25A1; the disease is lung carcinoma.