Downregulation of microRNA‐6125 promotes colorectal cancer growth through YTHDF2‐dependent recognition of N6‐methyladenosine‐modified GSK3β

Abstract

Background MicroRNAs (miRNAs), the key regulator of gene expression, and N6‐methyladenosine (m6A) RNA modification play a significant role in tumour progression. However, regulation of m6A‐modified mRNAs by miRNAs in colorectal cancer (CRC), and its effect on progression of CRC, remains to be investigated. Methods Expression of miR‐6125 and YTH Domain‐Containing Family Protein 2 (YTHDF2) was detected by western blotting and immunohistochemistry. The effects of miR‐6125 and YTHDF2 on proliferative capacity of CRC cells were analysed using soft agar, ATP, CCK8 and EdU assays, and in animal experiments. Results MiR‐6125 expression was downregulated markedly in CRC, and expression correlated negatively with tumour size and prognosis. MiR‐6125 targeted the 3′‐UTR of YTHDF2 and downregulated the YTHDF2 protein, thereby increasing the stability of m6A‐modified glycogen synthase kinase 3 beta ( GSK3β ) mRNA. Increased GSK3β protein levels inhibited the expression of Wnt/β‐catenin/Cyclin D1 pathway‐related proteins, leading to G0‐G1 phase arrest and ultimately inhibiting the proliferation of CRC cells. Conclusions MiR‐6125 regulates YTHDF2 and thus plays a critical role in regulating the Wnt/β‐catenin pathway, thereby affecting the growth of CRC. Collectively, these results suggest that miR‐6125 and YTHDF2 are potential targets for treatment of CRC.

m6A binding protein YTHDF2 in cancer

“…In summary, YTHDF2 may play an essential role in the prognosis of CRC. However, the protein levels of YTHDF2 were recently reported to be elevated in CRC tissues in comparison with adjacent normal tissues [ 49 ]. Overexpression of YTHDF2 facilitated the proliferation of CRC cells, suggesting that YTHDF2 may play a carcinogenic effect in CRC [ 49 ].…”

“…Glycogen synthase kinase 3 beta (GSK3β) is a crucial component of the Wnt/β-catenin pathway, and its inactivation causes β-catenin to concentrate in the cell and transfer to the nucleus to enhance the progression of tumors [ 87 , 88 ]. YTHDF2 was reported to recognize and bind m 6 A-modified GSK3β mRNA to promote its degradation, which subsequently decreased the phosphorylation of β-catenin to enhance the stability of the β-catenin protein, thereby promoting CRC cell proliferation [ 49 ]. Additionally, AXIN1, encoding a negative regulator of the Wnt/β-catenin pathway, was identified as a direct target of YTHDF2.…”

The Role of m6A Epigenetic Modification in the Treatment of Colorectal Cancer Immune Checkpoint Inhibitors

“…m6A Readers, ICIs in CRC Numerous studies on m6A Reader have confirmed four genes (YTHDF1, IGF2BP1, IGF2BP1, IGFBP3, EIF3B) is a potential biomarker of CRC. It was found to downregulate YTHDF1 or IMP2, can further regulate the GLS1-glutamine metabolic axis, improve the stability of the m6A-modified GSK3b mRNA, inhibition of Wnt/-catenin/cyclin D1 expression, inhibition of CRC cell proliferation, colony formation, and increase the apoptosis levels in CRC cells, To sensitized cisplatin-resistant CRC cells (126)(127)(128).…”

The N6-Methyladenosine Modification and Its Role in mRNA Metabolism and Gastrointestinal Tract Disease

“…Therefore, this study has no practical reference value. The WNT signaling pathway plays a pivotal role in CRC, and m6A also reportedly plays a role through this pathway (67,68,92,93). Song et al (92) found that m6A is related to the occurrence of CRC, which is caused by METTL3 and related to the WNT signaling pathway.…”

“…However, this study also has some shortcomings, such as a small clinical sample size and many results from a database analysis. In addition to YTHDF1, YTHDF2 also affects the growth of CRC through the Wnt/β-catenin pathway (93).…”