CAFs contribute to chemotherapy resistance through multiple mechanisms, such as CAFs upregulating glutathione levels in prostate cancer and inhibit reactive oxygen species (ROS) production [17], facilitating natural immunity to RAF inhibitors in cancers with BRAF mutations [18], expressing CD10 and GPR77 exhibit intrinsic resistance to chemotherapy [14], and regulating the NF-κB signaling pathway via secreting interleukin-6 (IL-6) and interleukin-8 (IL-8) in CD10+GPR77+ CAFs. This evidence concerns the gene C5AR2 and cancer.