Next Generation Sequencing Facilitates Quantitative Analysis of normal and YTHDF2 Overexpressing SMMC7721 cells in normoxia and hypoxia condition

Dynamic N6-methyladenosine (m6A) modification was previously identified as a ubiquitous post-transcriptional regulation that affected mRNA homeostasis. However, the m6A-related epitranscriptomic alterations and functions remain elusive in human diseases such as cancer. Here we show that hypoxia restrains the ‘reader’ protein YTH domain family 2 (YTHDF2), to stabilize the methylated oncogene mRNAs in inflammation-associated liver cancer. YTHDF2 silenced in human cancer cells or depleted in mouse hepatocytes evoked pro-inflammatory responses and accelerated tumor growth and metastatic progression. Under hypoxia, YTHDF2 processed the decay of m6A-containing interleukin 11 (IL11) and serpin family E member 2 (SERPINE2) mRNAs, which were responsible for the inflammation-mediated malignancy. Reciprocally, YTHDF2 transcription succumbed to hypoxia-inducible factor-2α (HIF-2α). Administration of a HIF-2α antagonist (PT2385) restored YTHDF2-programed epigenetic machinery and repressed liver cancer. Hence, our findings provide a new insight into the mechanism by which hypoxia adapts m6A-mRNA editing to promote cancer. Normal and YTHDF2 overexpressing SMMC7721 cells were cultured in normoxia and hypoxia conditions. mRNA profiles of all four cells were generated by deep sequencing with Illumina HiSeq X