Gly-tRF enhances LCSC-like properties and promotes HCC cells migration by targeting NDFIP2

Abstract

Background Accumulating evidence demonstrates that tRFs (tRNA-derived small RNA fragments) and tiRNAs (tRNA-derived stress-induced RNA), an emerging category of regulatory RNA molecules derived from transfer RNAs (tRNAs), are dysregulated in in various human cancer types and play crucial roles. However, their roles and mechanisms in hepatocellular carcinoma (HCC) and liver cancer stem cells (LCSCs) are still unknown. Methods The expression of glycine tRNA-derived fragment (Gly-tRF) was measured by qRT-PCR. Flow cytometric analysis and sphere formation assays were used to determine the properties of LCSCs. Transwell assays and scratch wound assays were performed to detect HCC cell migration. Western blotting was conducted to evaluate the abundance change of Epithelial-mesenchymal transition (EMT)-related proteins. Dual luciferase reporter assays and signalling pathway analysis were performed to explore the underlying mechanism of Gly-tRF functions. Results Gly-tRF was highly expressed in HCC cell lines and tumour tissues. Gly-tRF mimic increased the LCSC subpopulation proportion and LCSC-like cell properties. Gly-tRF mimic promoted HCC cell migration and EMT. Loss of Gly-tRF inhibited HCC cell migration and EMT. Mechanistically, Gly-tRF decreased the level of NDFIP2 mRNA by binding to the NDFIP2 mRNA 3′ UTR. Importantly, overexpression of NDFIP2 weakened the promotive effects of Gly-tRF on LCSC-like cell sphere formation and HCC cell migration. Signalling pathway analysis showed that Gly-tRF increased the abundance of phosphorylated AKT. Conclusions Gly-tRF enhances LCSC-like cell properties and promotes EMT by targeting NDFIP2 and activating the AKT signalling pathway. Gly-tRF plays tumor-promoting role in HCC and may lead to a potential therapeutic target for HCC.

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

“…Coincidentally, we note that Zhou et al's study 15 found that another tRF derived from tRNA‐Gly has a promoting effect on HCC cell migration by targeting NDFIP2. The sequence we researched (MINTbase‐ID: tRF‐22‐P4R8YP9LL) has a different source of mature tRNA than the Gly‐tRF in their article (MINTbase‐ID: tRF‐23‐PNR8YP9LD6).…”

Emerging roles of tRNA-derived fragments in cancer

“…Besides, plasma exosomal tRFs (tRNA-ValTAC-3, tRNAGlyTCC-5, tRNA-ValAAC-5 and tRNA-GluCTC-5) could serve as novel biomarkers for the diagnosis of liver cancer [ 156 ]. In terms of mechanisms, an HCC-upregulated tRF Gly-tRF enhanced liver cancer stem cell-like properties and promoted EMT by targeting NDFIP2 and activating the AKT signaling pathway [ 155 ]. In addition, Cho et al identified a distinct set of pre-tRNA 3’ trailer-derived tRFs by analyzing the profiles of small RNAs in Huh7 cells and human liver biopsies, which could sequester nuclear-cytoplasmic shuttling protein La/SSB in the cytoplasm by direct binding with their 3’U-tails, thus negatively regulating La/SSB-dependent viral gene expression [ 82 ].…”

Transfer RNA-derived small RNA: an emerging small non-coding RNA with key roles in cancer

“…In hepatocellular carcinoma (HCC), Gly-tRF targets Nedd4 family interacting protein 2 (NDFIP2) to promote the growth of HCC cells. Through analysis, NDFIP2 was found to regulate the AKT signaling pathway via ubiquitination of downstream target proteins, thereby regulating the malignant progression of HCC [ 87 ]. The expression of tRF-315 was increased in prostate cancer (PC) cells and could inhibit cisplatin-induced apoptosis.…”