As for CAF-related gene fibroblast growth factor-1 (FGF-1), underlying mechanisms regulating tumor progression include phosphorylation of FGF-4, activation of the mitogen-activated protein kinase/extracellular signal-regulated protein kinase (MAPK/ERK) pathway, and also upregulated expression of EMT-related genes, such as Snail-1 and MMP3 [50]. This evidence concerns the gene MMP3 and neoplasm.