These oncogenes, such as GDNF, STAT3, and SOX1, induce CAF activation and promote the overexpression of growth factors such as CXCL12 and Wnt/Notch for differentiating epithelial cells into tumor-initiating stem cells (Hirano et al., 2000; Shan et al., 2015). This evidence concerns the gene GDNF and neoplasm.