Transferrin Receptor Promotes Endometrial Cancer Proliferation by Activating the Iron‐Dependent PI3K/AKT/mTOR Signaling Pathway

ABSTRACT Aberrant iron metabolism is frequently observed in cancers, including endometrial cancer (EC). However, the role of transferrin receptor (TFRC), a key regulator of iron metabolism, remains unclear in endometrial cancer. We found transferrin receptor expression was significantly upregulated in endometrial cancer tissues compared to adjacent nontumor tissues, and high transferrin receptor levels were associated with poor prognosis. Functional studies revealed that transferrin receptor knockdown impaired endometrial cancer cell proliferation in vitro and in vivo, while transferrin receptor overexpression enhanced endometrial cancer cell proliferation. Mechanistically, transferrin receptor activated the PI3K/AKT/mTOR signaling pathway, as its knockdown suppressed the pathway, and rapamycin, an mTOR inhibitor, reversed transferrin receptor‐induced pathway activation and proliferation. Modulation of the labile iron pool by ferric ammonium citrate (FAC) or deferoxamine (DFO) rescued transferrin receptor‐induced biological effects. Additionally, AURKA was identified as a regulator of transferrin receptor expression. These findings demonstrate the oncogenic role of transferrin receptor in endometrial cancer and suggest that targeting iron homeostasis and the PI3K/AKT/mTOR pathway may represent potential therapeutic strategies for endometrial cancer.