Abstract
tRNA-derived fragments (tRFs) are derived from corresponding tRNAs and have been shown by several studies to be novel biological markers for tumour diagnosis and therapy. However, until now, the effects of tRFs on the progression of colorectal cancer (CRC) and especially on the epithelial-to-mesenchymal transition (EMT) have remained unknown. Our study aimed to assess CRC-related tRFs and examine the effects of key tRFs on CRC progression and related mechanisms. After hypoxic treatment, tRF sequencing and real-time PCR assays were performed to identify key tRFs. Then, functional tests were designed to verify the effects and evaluate the mechanism after cell transfection under normoxic conditions. A total of 14 tRFs were differentially expressed in the hypoxia and control groups. Based on the results of PCR assay verification and conditional selection, tRF-20-M0NK5Y93 could be a promising target for exploration, as its expression was significantly lower under hypoxic conditions than under control conditions. tRF-20-M0NK5Y93 inhibited CRC cell migration and invasion partly by targeting Claudin-1, an EMT-related molecule. The results of the present study suggest that tRF-20-M0NK5Y93 promotes CRC cell migration and invasion partly by regulating Claudin-1 during EMT.