Fig. 1

Let-7a is enriched in serum-derived EVs from CRC patients. EVs isolated from serum of CRC patients or heathy controls (HC) using ultracentrifugation (UC) were confirmed by transmission electron microscopy (a) and Nanosight particle tracking analysis (b). Scale bar, 100 nm. c qPCR analysis of let-7a from serum EVs of CRC patients (n = 13) and HC (n = 13) isolated by UC methods, with U6 as the loading control. d qPCR analysis of let-7a from serum EVs of CRC patients (n = 31) and HC (n = 25) isolated by precipitation methods, with U6 as the loading control. e Comparative analysis of serum EV let-7a in CRC patients (n = 88) and HC (n = 11) from the Database: GSE40247. f ROC curves for the diagnostic values of serum EV let-7a and CEA in CRC patients (n = 31) and HC (n = 25). g, h Let-7a expression in CRC patient tumor (T) tissue with paired adjacent non-tumor (NT) samples (n = 31). (i) Let-7a expression between CRC (T, n = 450) and non-tumor (NT, n = 8) tissue from TCGA database are shown. Data represent the mean ± SEM of at least three independent experiments. *p < 0.05, **p < 0.01 and ***p < 0.001