Exosomes derived from prostate cancer cells can upregulate CXC motif receptor 4 (CXCR4) via the TLR2/NF-κB signaling pathway, eventually promoting the migration of MDSCs into the tumor microenvironment in a CXCR4–CXCL12 axis-dependent manner (100). The gene discussed is CXCR4; the disease is prostate cancer.