tRNA fragments (tRFs) are a recently identified group of noncoding RNAs. Initially the presence of tRFs in deep sequencing studies was attributed to the breakdown of mature tRNAs; however, it is now clear that they are actively generated and participate in numerous regulatory mechanisms. One such tRF, tRF5-Glu, is encoded within the 5’ region of the mature tRNA-Glu-CTC and widely expressed in deep sequencing studies of extracellular RNA (exRNA). exRNA is expected to provide physiologically relevant biomarkers in liquid biopsy samples, such as serum, plasma, or urine from cancer patients. These researchers initially identified the expression of tRF5-Glu in urine from ovarian cancer patients. They have confirmed the expression of tRF5-Glu in ovarian cancer cell lines using northern analysis, qRT-PCR, and ligation PCR. They also studied the biogenesis of tRF5-Glu in ovarian cancer cells using antisense suppression of angiogenin (ANG). Furthermore, they characterized the tRF5-Glu regulation of two target mRNAs, BCAR3, and PCGF2. They found that tRF5-Glu binds to multiple mRNA targets thereby regulating protein expression. Additionally, the researchers have shown that tRF5-Glu inhibits cancer cell proliferation in vitro. These studies provide new understanding of the biogenesis and function of tRFs in ovarian cancer.
Research by this group was featured on the MSI website in August 2023: Genetic Investigations of SARS-CoV-2.