CXCL12 and cancer: In cancer, TGF-β and integrins synergistically promote invasion and metastasis: for instance, in triple-negative breast cancer, tumor cells activate TGF-β signaling via αvβ6 integrin, inducing upregulation of the transcription factor SOX4 to facilitate immune evasion (68); In colorectal cancer, αvβ6 on tumor cells activates paracellular fibroblasts via TGF-β, which then secrete SDF-1 to stimulate cancer cell migration and invasion (69).