Relationship Between Low Expressions of tRNA-Derived Fragments with Metastatic Behavior of Colorectal Cancer.

Purpose: Colorectal cancer (CRC) is one of the most commonly diagnosed malignant tumors and highly heterogeneous diseases. More recently, RNA expression profiles have been used as prognostic cancer markers. In this regard, the expression of small non-coding RNAs like tRNA-derived fragments (tRFs) in tumor tissue has potential diagnostic values in metastatic cancer.

Method: Sixty postoperative CRC tissue samples, consisting of 30 cancers and 30 adjacent normal tissues, were collected from cancer patients. We evaluated MINTbase database to select tRNA-derived fragments. The expression levels of miR-1280, miR1308, tRNA-Val, and tRNA-Asp were measured by TaqMan quantitative reverse transcription PCR technology. Also, we have evaluated the correlation between the levels of tRFs gene expression and clinicopathological of CRC disease.

Result: The three tRFs derived from tRF/miR-1280, tRNA-Val, and tRNA-Asp downregulated in tumor tissues (all, p < 0.0001). These tRFs have lower expression in stage IV in comparison with stage III. The tRFs derived from tRNA-Val (p = 0.005) and tRNA-Asp (p = 0.034) showed the decreased expression in CRC patients with distant metastasis.

Conclusion: The present study demonstrated that low expression of tRF/miR-1280, tRNA-Val, and tRNA-Asp was significantly associated with metastatic stage and more aggressive tumor behavior of CRC disease. Our finding promising the potential of using tRFs as biomarkers for cancer diagnosis.