Bioactive peptide inhibits acute myeloid leukemia cell proliferation by downregulating ALKBH5-mediated m6A demethylation of EIF4EBP1 and MLST8 mRNA

Purpose N6-methyladenosine (m(6)A), the most prevalent mRNA modification, plays an essential role in tumorigenesis. Notably, increasing interest has been directed to bioactive peptides (BPs) with antitumor activities. Here, we set out to investigate the potential of the BP-regulated ALKBH5/MLST8/EIF4EBP1 axis on prevention and treatment of acute myeloid leukemia (AML). Methods The biological effects of BP on AML cells were detected by MTT and ApoLive-Glo (TM) multiplex assays. The role of BP in tumor growth was determined by a subcutaneous xenograft model. The ALKBH5/MLST8/EIF4EBP1 axis was identified as a potential BP target in AML via methylated RNA immunoprecipitation sequencing (MeRIP-seq) combined with RNA sequencing (RNA-seq). Western blot, RT-qPCR, MeRIP-qPCR, dual-luciferase reporter and RNA stability assays were performed to validate the function and mode of action of the BP-regulated ALKBH5/MLST8/EIF4EBP1 axis. The clinical relevance of the BP-regulated ALKBH5/MLST8/EIF4EBP1 axis in AML was confirmed by TCGA data analysis. Results We found that BP can inhibit AML cell proliferation and promote apoptosis in vitro, and repress AML tumor growth in vivo. Mechanistically, we found that BP downregulated ALKBH5 expression, which in turn repressed m(6)A demethylation of MLST8 and EIF4EBP1 mRNAs. Reduction of the m(6)A levels of MLST8 and EIF4EBP1 facilitated MLST8 and EIF4EBP1 mRNA decay, resulting in inhibition of AML cell proliferation. Furthermore, we found that the BP-regulated ALKBH5/MLST8/EIF4EBP1 axis closely correlates with AML patient prognosis. Conclusions Our data indicate that BP can inhibit acute myeloid leukemia cell proliferation by downregulating ALKBH5-mediated m(6)A demethylation of EIF4EBP1 and MLST8 mRNAs, which may have potential to prevent and treat this disease.