Journal Article

RNA demethylase ALKBH5 prevents pancreatic cancer progression by posttranscriptional activation of PER1 in an m6A-YTHDF2-dependent manner

Li, Kai, Hu, Yangyang, Xiao, Wenqin, Huang, Yinshi, Jiang, Weiliang, Guo, Xingya, Pan, Qin, Wan, Rong, Feng, Yun

2020

Overview

Background N6-methyladenosine (m6A) is the most abundant reversible methylation modification of eukaryotic mRNA, and it plays vital roles in tumourigenesis. This study aimed to explore the role of the m6A demethylase ALKBH5 in pancreatic cancer (PC). Methods The expression of ALKBH5 and its clinicopathological impact were evaluated in PC cohorts. The effects of ALKBH5 on the biological characteristics of PC cells were investigated on the basis of gain-of-function and loss-of-function analyses. Subcutaneous and orthotopic models further uncovered the role of ALKBH5 in tumour growth. mRNA and m6A sequencing and assays of m6A methylated RNA immunoprecipitation-qPCR (MeRIP-qPCR) were performed to identify the targeted effect of ALKBH5 on PER1. P53-binding sites in the ALKBH5 promoter were investigated by ChIP and luciferase assays to reveal the interplay between ALKBH5 and PER1-activated ATM-CHK2-P53/CDC25C signalling. Results ALKBH5 loss characterized the occurrence and poor clinicopathological manifestations in patients with PC. Overexpression of ALKBH5 reduced tumoural proliferative, migrative, invasive activities in vitro and ameliorated tumour growth in vivo, whereas ALKBH5 knockdown facilitated PC progression. Mechanistically, ALKBH5 posttranscriptionally activated PER1 by m6A demethylation in an m6A-YTHDF2-dependent manner. PER1 upregulation led to the reactivation of ATM-CHK2-P53/CDC25C signalling, which inhibited cell growth. P53-induced activation of ALKBH5 transcription acted as a feedback loop regulating the m6A modifications in PC. Conclusion ALKBH5 serves as a PC suppressor by regulating the posttranscriptional activation of PER1 through m6A abolishment, which may highlight a demethylation-based approach for PC diagnosis and therapy.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Adenosine - analogs & derivatives / Adenosine - chemistry / AlkB Homolog 5, RNA Demethylase - genetics / AlkB Homolog 5, RNA Demethylase - metabolism / ALKBH5 / Analysis / Animals / Antibodies / Apoptosis / Binding sites / Bioinformatics / Biomarkers, Tumor - genetics / Biomarkers, Tumor - metabolism / Biomedical and Life Sciences / Biomedicine / Cancer prevention / Cancer Research / Cell activation / Cell Movement / Cell Proliferation / Demethylation / Development and progression / Female / Gene Expression Regulation, Neoplastic / Genomes / Humans / Immunoprecipitation / Invasiveness / m6A / Male / Methylation / Methyltransferases / Mice / Mice, Nude / Middle Aged / N6-methyladenosine / Neoplasm Invasiveness / Non-coding RNAs and RNA modifiers in cancer progression and cancer cells resistance to therapies / Oncology / p53 Protein / Pancreatic cancer / Pancreatic Neoplasms - genetics / Pancreatic Neoplasms - metabolism / Pancreatic Neoplasms - pathology / PER1 / Period 1 protein / Period Circadian Proteins - genetics / Period Circadian Proteins - metabolism / Pheochromocytoma cells / Plasmids / Post-transcription / Prognosis / RNA / RNA modification / RNA Processing, Post-Transcriptional / RNA-Binding Proteins - genetics / RNA-Binding Proteins - metabolism / RNA-protein interactions / Software / Survival Rate / Transcription activation / Transcriptional Activation / Tumor Cells, Cultured / Tumor proteins / Tumorigenesis / Tumors / Xenograft Model Antitumor Assays