Abstract:

Objective To detect the expression level of microRNA-92a-3p （miR-92a-3p） in the exosome in serum exosome of the patients with acute myeloid leukemia （AML）， and to explore its diagnostic value for AML. Methods A total of 51 patients with AML （AML group） and 34 physically healthy volunteers during the same period（control group） were selected as subjects，and the peripheral blood specimens of the subjects were collected，and the peripheral blood specimens were collected from the subjects. The serum exosomes were extracted by differential centrifugation，and identified by transmission electron microscope， nanoparticle analyzer and Western blotting method；the expression levels of miR-92a-3p in serum exosome of the subjects in two groups were detected by real-time fluorescence quantitative PCR（RT-qPCR） method；according to the expression level of miR-92a-3p in serum exosome， the receiver operating characteristic（ROC） curve was drawn and the area under the curve （AUC） was calculated to determine the critical value， and the diagnostic efficiency of expression level of miR-92a-3p to AML was evaluated based on the sensitivity and specificity. Results The extracted exosomes had membrane structures with round appearance and concave in the middle under transmission electron microscope； the size of the exosomes was 30－100 nm detected by nanoparticle analyzer；the expressions of CD63 and CD9 proteins were found by Western blotting method.Compared with control group，the expression level of miR-92a-3p in serum exosome of the patients in AML group was significantly decreased（P<0.01）；the ROC curve results showed that the optimal critical value of serum exosome miR-92a-3p for the diagnosis of AML was 0.51， the sensitivity was 76.47%， the specificity was 94.12%，the AUC was 0.913，95% confidence interval（CI）=（0.856，0.971）（P<0.001）. Conclusion The expression level of miR-92a-3p in serum exosome of the AML patients has high sensitivity and specificity in the diagnosis of AML， and it can be used in the clinical diagnosis of early AML.

Key words: Acute myeloid leukemia, Exosome, MicroRNA-92a-3p, Tumor marker