Abstract:  Exosomes， as bilayer lipid vesicles secreted by various cell types， including tumor cells ， are enriched with bioactive molecules such as transfer RNA⁃derived small RNAs (tsRNAs) ， which play a crucial role in cellular communication. tsRNAs originate from precursor tRNAs or mature tRNAs， and their expression levels vary significantly in the body fluids of cancer patients. Exosome⁃derived tsRNAs are abundantly present in the plasma， saliva， and other body fluids of cancer patients. Recent studies have shown that these tsRNAs are involved in regulating tumor cell proliferation， invasion， metastasis， and drug resistance. Moreover， due to their stability and tissue specificity， tsRNAs exhibit significant potential as clinical biomarkers for tumors in liquid biopsies. This review provides a comprehensive summary of the biological functions of exosome⁃derived tsRNAs in tumors and their promising applications as biomarkers in tumor diagnosis and treatment.

Key words: Tumor, Exosome, Transfer RNA?derived small RNAs, Biomarker