RUNX3 drives HTR-8/SVneo cell ferroptosis and spontaneous abortion: involvement of the suppression of GDF15 transcriptional activity.

Spontaneous abortion (SA) refers to the loss of a pregnancy without external intervention. The runt-related transcription factor 3 (RUNX3) is associated with gestational disorders in view of previous studies. However, RUNX3 has not been reported in SA. RUNX3 is significantly upregulated in the placental villi of abortion patients based on the GSE123719 microarray data. Herein, we further validated and found that the expression of RUNX3 in placental villi of SA women was higher than those of induced abortion (IA) women. In vitro, we constructed human RUNX3 overexpression or interference adenovirus vectors to modulate RUNX3 expression in trophoblast cells. Our findings revealed that RUNX3 overexpression accelerated trophoblast cell ferroptosis, while RUNX3 knockdown alleviated erastin-induced ferroptosis. Subsequently, the dual luciferase reporter assay was performed to confirm that RUNX3 bound to the GDF15 promoter to transcriptionally repress GDF15 transcriptional activity. Importantly, GDF15 attenuated the pro-ferroptosis effects of RUNX3 on HTR-8/SVneo cells. In vivo, mouse RUNX3 interference adenovirus vectors were used to silence RUNX3 in mice. The results presented that the reduction of RUNX3 inhibited embryo adsorption rate in SA mice, involving ferroptosis and the interaction between RUNX3 and GDF15. Taken together, this study established that RUNX3 advanced SA progression by enhancing trophoblast ferroptosis via transcriptionally repressing GDF15. These findings may provide novel therapeutic strategies for SA management.