Taken together, our data suggest that the 15 plasma exosomal RNAs from the three classes of miRNA, mRNAs, and snoRNAs distinguish the normal and cancer groups by reflecting the evasion of tumor suppression (miR-142-3p and ARL6IP5), tumor proliferation (KIF2A), tumor progression through the TME (CXCL5 and RGS18), and cancer immunity (DAPP1 and 9 snoRNAs). The gene discussed is RGS18; the disease is cancer.