SLC25A48 promotes colorectal cancer growth by enhancing mitochondrial respiration and conferring ferroptosis resistance.

Accumulating evidence indicates that mitochondrial dysfunction is a hallmark of cancer. Nonetheless, the mechanisms linking mitochondrial dysfunction to cancer progression remain largely elusive. SLC25A48 was recently recognized as a transporter involved in mitochondrial choline uptake. Nevertheless, the roles of SLC25A48 in human malignancies remain unexplored. Here, we found that SLC25A48 is elevated in colorectal cancer (CRC) tissues and associates with unfavorable patient outcomes. Functional analyses showed that SLC25A48 accelerates the growth of CRC by enhancing proliferative capacity and preventing cell death. Mechanistically, SLC25A48 exerts its oncogenic function by enhancing the synthesis of choline-derived betaine, which is an important source of one-carbon units for numerous biosynthetic processes. On the one hand, SLC25A48 mitigates oxidative stress-induced ferroptosis by augmenting NADPH availability. On the other hand, it enhances cell proliferation by promoting mitochondrial energy production through upregulating mitochondrial DNA (mtDNA) replication and transcription. Importantly, silencing of SLC25A48 augmented the responsiveness of CRC cells to RSL3-induced ferroptosis and 5-FU-based chemotherapy. Furthermore, increased CTCF expression may contribute, at least in part, to the upregulation of SLC25A48 in CRC. Collectively, our data emphasize that SLC25A48 plays a critical oncogenic role in CRC and holds potential as a druggable target to overcome drug resistance in CRC.