CXCL12 and cancer: Several studies have shown that typical immune signaling pathways, such as CXCL12-CXCR4, VEGF-VEGFR, IL-6-JAK-STAT3, and TGF-β-TGFβR, are They are widely present in the interactions among cancer cells, CAFs, TAMs, MDSCs, Tregs and TILs, and regulate the homing, differentiation, depletion and rejection of immune cells, thus solidifying the “rejection-type” and “desert-type” immune phenotypes.