Transfer RNA‐derived fragment 5′tRF‐Gly promotes the development of hepatocellular carcinoma by direct targeting of carcinoembryonic antigen‐related cell adhesion molecule 1

Transfer RNA‐derived fragments are a group of small noncoding single‐stranded RNA that play essential roles in multiple diseases. However, their biological functions in carcinogenesis are not well understood. In this study, 5′tRF‐Gly was found to have significantly high expression in hepatocellular carcinoma (HCC), and the upregulation of 5′tRF‐Gly was positively correlated with tumor size and tumor metastasis. Overexpression of 5′tRF‐Gly induced increased growth rate and metastasis in HCC cells in vitro and in nude mice, while knockdown showed the opposite effect. Carcinoembryonic antigen‐related cell adhesion molecule 1 (CEACAM1) was confirmed to be a direct target of 5′tRF‐Gly in HCC. In addition, the cytological effect of CEACAM1 knockdown proved to be similar to the overexpression of 5′tRF‐Gly. Moreover, attenuation of CEACAM1 expression rescued the 5′tRF‐Gly‐mediated promoting effects on HCC cells. These data show that 5′tRF‐Gly is a new tumor‐promoting factor and could be a potential diagnostic biomarker or new therapeutic target for HCC.