METTL1 mRNA expression is downregulated under hypoxia, and HIF-1α directly binds to the METTL1 promoter at HRE elements, repressing its transcription, revealing a mechanism by which the hypoxic microenvironment negatively regulates METTL1 and tRNA m7G modification in CRC. This evidence concerns the gene METTL1 and colorectal carcinoma.