PRODH and breast cancer: Proline oxidase/proline dehydrogenase (POX/PRODH), an enzyme associated with the inner mitochondrial membrane, plays an essential role in breast cancer cell growth and metastasis by converting proline to pyrroline-5-carboxylate (P5C) and generating FADH2, which provides electrons for the ECT and promotes ATP production (Zhou et al., 2019).