Figure 1(a) shows that U937 cultured with CAFs-CM presented a remarkable M2 polarization, as evidenced by the increased expression of CD163, CD206, and IL-10 (classic M2 signature markers). Although CAFs-CM enhanced the mRNA and protein levels of CD163, CD206, and IL-10 compared with NFs-CM, GW4869 (a specific exosome inhibitor)-treated CAFs partially lost its potential to induce macrophage M2 polarization (Figures 1(b)–1(d)). Functionally, CAFs-CM promoted PCa cell proliferation and invasion versus NFs-CM, whereas GW4869 treatment significantly destroyed the effect (Figures 1(e) and 1(f)). Here, MRC1 is linked to posterior cortical atrophy.