In the final step, Western blot experiments revealed that CD9 and Hsp70, known markers for exosomes, were enriched in the serum of CRC patients, while their expression was not detected in CRC cells (SW480 and HCT‐116), and GM130 (negative control) was expressed in CRC cells but not in exosomal extracts (Figure 2C). Here, CD9 is linked to colorectal carcinoma.