Hypoxia Triggers ALYREF-Mediated m(5)C Methylation of KIF20A to Activate KIF20A/BUB1 for Generating Ferroptosis Resistance in Cervical Cancer Cells.

Ferroptosis resistance is a key player in cervical cancer (CC) development. Hypoxia is a negative factor affecting CC treatment by inducing ferroptosis resistance. Our study aimed to investigate the detailed mechanisms of hypoxia-induced ferroptosis resistance in CC cells. The mRNA and protein levels were assessed using RT-qPCR and western blot. Immunofluorescence staining was used to analyze the co-localization of Budding uninhibited by benzimidazole 1 (BUB1) and Kinesin family member 20A (KIF20A) in CC cells. Fe(2+), MDA, and GSH levels were measured by commercial kits. Cell viability was determined by CCK-8. The molecular interactions were analyzed by RIP or Co-IP. MeRIP was adopted to measure the m(5)C level of KIF20A. We found that hypoxia facilitated ferroptosis resistance in CC cells. Hypoxia led to the upregulation of KIF20A, and KIF20A knockdown weakened hypoxia-mediated ferroptosis resistance in CC cells. Mechanistically, Aly/REF export factor (ALYREF) stabilized KIF20A mRNA stability via m(5)C modification. In addition, KIF20A upregulated BUB1 in CC cells by directly interacting with BUB1. Rescue experiments indicated that BUB1 overexpression partially reversed the inhibitory effect of KIF20A knockdown on hypoxia-mediated ferroptosis resistance in CC cells. In conclusion, hypoxia triggers ALYREF-mediated m(5)C methylation of KIF20A to activate the KIF20A/BUB1 axis, thereby inducing ferroptosis resistance in CC cells.