In GC cells, CAFS has been shown to promote angiogenesis by secreting FGF, IL-6, PDGF and VEGF and promote EMT by secreting transforming growth factor beta (TGF-β), FGF, TNF-α, and IL-1β, in turn leading to proliferation, invasion and metastasis of GC (39, 42–49)(Figure 2). Here, IL6 is linked to gastric cancer.