MiR-339-5p Inhibits Ferroptosis by Promoting Autophagic Degradation of FTH1 Through Targeting ATG7 in Liver Cancer Cells

Abstract

Background: Liver cancer has a high incidence and mortality rate worldwide, and there is an urgent need to identify new therapeutic strategies and predictive targets to improve the clinical outcomes of advanced liver cancer. Ferroptosis holds promise as a novel strategy for cancer therapy. Epigenetic dysregulation is a hallmark of cancer, and noncoding RNAs are tightly involved in cell fate determination. Therefore, we aimed to identify a novel ferroptosis regulator from aberrantly expressed microRNAs that may serve as a novel biomarker and therapeutic target for liver cancer. Methods: The expression signature and prognostic value of miR-339 was assessed using TCGA data set. The role of miR-339/ATG7/FTH1 axis in liver cancer cells were evaluated through growth curve, colony formation, 7-AAD staining. The role of miR-339 in regulation of ferroptosis was determined by immunofluorescence staining, flow cytometry, and Elisa kits. Results: Here, we showed that miR-339 is aberrantly overexpressed in patients with liver cancer. In addition, miR-339 inhibition dramatically suppresses liver cancer progression. Furthermore, miR-339 silencing drives cell death and inhibits liver cancer progression, indicating that miR-339 may serve as a novel ferroptosis suppressor. Mechanistically, we demonstrated that miR-339 targets ATG7 to facilitate the autophagic degradation of FTH1 and prevent ferroptosis in liver cancer cells. Conclusions: We provide important evidence that the miR-339 inhibition activates of the autophagy pathway to promote ferroptosis by degrading FTH1 in liver cancer cells. We found that miR-339 regulates the balance between ferroptosis and autophagy in liver cancer cells.

Bismuth Sulfide Nanoflowers Facilitated miR339 Delivery to Overcome Stemness and Radioresistance through Ubiquitin-Specific Peptidase 8 in Esophageal Cancer

“…28 Besides, miR339 inhibits ferroptosis by promoting autophagic degradation of FTH1 through targeting ATG7 in liver cancer cells. 29 However, whether miR339 acts as a radiosensitizer to facilitate therapeutic efficacy remains unclear. Here, we found that miR339 was involved in stem cell division and DNA checkpoint signaling pathways based on our ESCC cohort, 30 and USP8, a direct target of miR339, promotes radioresistance by maintaining ESCC cell stemness and inhibiting DNA damage in vitro.…”

“…Recently, the miR339/KEAP1/Nrf2 axis was found to promote the macrophage M1-to-M2 transition and ischemic flap survival . Besides, miR339 inhibits ferroptosis by promoting autophagic degradation of FTH1 through targeting ATG7 in liver cancer cells . However, whether miR339 acts as a radiosensitizer to facilitate therapeutic efficacy remains unclear.…”