N6-methyladenosine reader IMP2 stabilizes the ZFAS1/OLA1 axis and activates the Warburg effect: implication in colorectal cancer

Abstract

Background Accumulating evidence shows that N6-methyladenine (m6A) modulators contribute to the etiology and progression of colorectal cancer (CRC). However, the exact mechanisms of m6A reader involved in glycolytic metabolism remain vague. This article aimed to crosstalk the m6A reader with glycolytic metabolism and reveal a new mechanism for the progression of CRC. Methods The relationship between candidate lncRNA and m6A reader was analyzed by bioinformatics, ISH and IHC assays. In vivo and in vitro studies (including MTT, CFA, trans-well, apoptosis, western blot, qRT-PCR and xenograft mouse models) were utilized to explore the biological functions of these indicators. Lactate detection, ATP activity detection and ECAR assays were used to verify the biological function of the downstream target. The bioinformatics, RNA stability, RIP experiments and RNA pull-down assays were used to explore the potential molecular mechanisms. Results We identified that the crosstalk of the m6A reader IMP2 with long-noncoding RNA (lncRNA) ZFAS1 in an m6A modulation-dependent manner, subsequently augmented the recruitment of Obg-like ATPase 1 (OLA1) and adenosine triphosphate (ATP) hydrolysis and glycolysis during CRC proliferation and progression. Specifically, IMP2 and ZFAS1 are significantly overexpressed with elevated m6A levels in CRC cells and paired CRC cohorts (n = 144). These indicators could be independent biomarkers for CRC prognostic prediction. Notably, IMP2 regulated ZFAS1 expression and enhanced CRC cell proliferation, colony formation, and apoptosis inhibition; thus, it was oncogenic. Mechanistically, ZFAS1 is modified at adenosine +843 within the RGGAC/RRACH element in an m6A-dependent manner. Thus, direct interaction between the KH3–4 domain of IMP2 and ZFAS1 where IMP2 serves as a reader for m6A-modified ZFAS1 and promotes the RNA stability of ZFAS1 is critical for CRC development. More importantly, stabilized ZFAS1 recognizes the OBG-type functional domain of OLA1, which facilitated the exposure of ATP-binding sites (NVGKST, 32–37), enhanced its protein activity, and ultimately accelerated ATP hydrolysis and the Warburg effect. Conclusions Our findings reveal a new cancer-promoting mechanism, that is, the critical modulation network underlying m6A readers stabilizes lncRNAs, and they jointly promote mitochondrial energy metabolism in the pathogenesis of CRC.

The role of Insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) as m6A readers in cancer

“…In addition, lncRNA LINRIS stabilizes IGF2BP2 by blocking its ubiquitination to promote the c-MYC-driven glycolysis in colorectal cancer 157 . In colorectal cancer, IGF2BP2 directly binds to the m 6 A sites of lncRNA ZFAS1 and increases its stability to activate the Warburg effect 158 . Moreover, LINC01021 promotes tumorigenesis and progression through enhancing the mRNA stability of target transcripts, MSX1 and JARID2 in IGF2BP2- mediated m 6 A modification 159 .…”

Integrated Analysis of RNA Binding Protein-Related lncRNA Prognostic Signature for Breast Cancer Patients

“…Interestingly, one recent genome-wide analysis of lncRNA half-lives in humans revealed that RBP-lncRNA interactions mainly enhance the stability of lncRNA with only one exon [ 22 ]. Additionally, N6-methyladenosine (m6A) writers and erasers, as well as readers, are all RBPs that modulate m6A modification and function of lncRNAs [ 23 ], primarily by affecting their stability and changing their expression levels [ 24 , 25 , 26 ]. Recently, RBP has also been reported to regulate the transcription of lncRNA.…”

Identification and Validation of Genomic Subtypes and a Prognostic Model Based on Antigen-Presenting Cells and Tumor Microenvironment Infiltration Characteristics in Hepatocellular Carcinoma

“…The miRNA-133b/SF3B4 axis may serve as a new immunotherapeutic target for HCC treatment (54). The other hub genes (e.g., YBX1, OLA1, TRMT10C, and KIF20A) also play a key role in the development and prognosis of the pan-cancer section (55)(56)(57)(58). Meanwhile, the role of TIMM23, YARS1, and EIF2S1 in affecting HCC is still unclear.…”