RNA demethylase ALKBH5 regulates hypopharyngeal squamous cell carcinoma ferroptosis by posttranscriptionally activating NFE2L2/NRF2 in an m⁶ A-IGF2BP2-dependent manner.

ABSTRACT:

Background

Having emerged as the most abundant posttranscriptional internal mRNA modification in eukaryotes, N6-methyladenosine (m⁶ A) has attracted tremendous scientific interest in recent years. However, the functional importance of the m⁶ A methylation machinery in ferroptosis regulation in hypopharyngeal squamous cell carcinoma (HPSCC) remains unclear.

Methods

We herein performed bioinformatic analysis, cell biological analyses, transcriptome-wide m⁶ A sequencing (m⁶ A-seq, MeRIP-seq), RNA sequencing (RNA-seq), and RNA immunoprecipitation sequencing (RIP-seq), followed by m⁶ A dot blot, MeRIP-qPCR, RIP-qPCR, and dual-luciferase reporter assays.

Results

The results revealed that ALKBH5-mediated m⁶ A demethylation led to the posttranscriptional inhibition of NFE2L2/NRF2, which is crucial for the regulation of antioxidant molecules in cells, at two m⁶ A residues in the 3'-UTR. Knocking down ALKBH5 subsequently increased the expression of NFE2L2/NRF2 and increased the resistance of HPSCC cells to ferroptosis. In addition, m⁶ A-mediated NFE2L2/NRF2 stabilization was dependent on the m⁶ A reader IGF2BP2. We suggest that ALKBH5 dysregulates NFE2L2/NRF2 expression in HPSCC through an m⁶ A-IGF2BP2-dependent mechanism.

Conclusion

Together, these results have revealed an association between the ALKBH5-NFE2L2/NRF2 axis and ferroptosis, providing insight into the functional importance of reversible mRNA m⁶ A methylation and its modulators in HPSCC.

SUBMITTER: Ye J 

PROVIDER: S-EPMC9279968 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature