Lung cancer is one of the deadliest cancers in the world because of chemo-resistance to the commonly used cisplatin-based treatments. The use of low fidelity DNA polymerases in the translesional synthesis (TLS) DNA damage response pathway that repairs lesions caused by cisplatin also presents a mutational carcinogenic burden on cells that needs to be regulated by the tumor suppressor protein p53. However, there is much debate over the roles of the reversionless 3-like (REV3L) protein responsible for Us and p53 in regulating cancer cell metabolism. In this study, the fluorescence lifetime of the metabolic coenzyme NADH reveals that the absence of REV3L can promote the p53-mediated upregulation of oxidative phosphorylation in cisplatin-treated H1299 lung carcinoma cells and increases cancer cell sensitivity to this platinum-based chemotherapy. These results demonstrate a previously unrecognized relationship between p53 and REV3L in cancer cell metabolism and may lead to improvements in chemotherapy treatment plans that reduce cisplatin resistance in lung cancer. (C) 2018 Published by Elsevier Inc.