CXCL12 and cancer: Because the exp‐CAFs are conferred the potent ability to induce tumor growth, invasion and metastasis and showed enhanced expression of TGF‐β, SDF‐1, and α‐SMA,20, 21 which are typical CAF signatures, they can be a useful experimental tool to gain a deeper understanding of CAFs' characteristics and their communication with cancer cells in the tumor microenvironment.