Abstract
BACKGROUND: Gastric cancer (GC) is a malignant tumor of the gastrointestinal system. Since the early symptoms of GC are not obvious and lack efficient diagnostic markers, it is urgent to find new diagnostic markers with good sensitivity and specificity. tRNA-derived small RNAs (tsRNAs) are an emerging class of small noncoding RNAs with good abundance in body fluids. We aim to find new tsRNAs as biomarkers for GC diagnosis. METHODS: High-throughput sequencing was used to identify differentially expressed tsRNAs in GC tissues, and quantitative real-time PCR was used to detect the expression level of tRF-17-WS7K092. Agarose gel electrophoresis and Sanger sequencing were performed to verify the characteristics of tRF-17-WS7K092. The diagnostic efficacy of tRF-17-WS7K092 was analyzed by the receiver operating characteristic curve. RESULTS: In this study, the expression levels of tRF-17-WS7K092 were significantly increased in GC tissues, cells, and serum. After GC surgery, the expression level of serum tRF-17-WS7K092 decreased, and its high expression was associated with low survival rates. In addition, the expression level of serum tRF-17-WS7K092 was correlated with the T stage, TNM stage, lymph node metastasis, and nerve/vascular invasion and could distinguish GC patients from gastritis patients and healthy donors as well. CONCLUSIONS: The expression of serum tRF-17-WS7K092 was significantly increased in GC and decreased after GC surgery, suggesting that serum tRF-17-WS7K092 may serve as a promising biomarker for the diagnostic and prognostic monitoring of GC.