CAFs positive for both fibroblast activation protein (FAP) and α-SMA have been found to inhibit the proliferation of CD8+ cytotoxic T cells, and TGF-β and VEGF derived from cancer cells and CAFs to promote the recruitment of CD4+CD25+ Tregs, in head and neck squamous cell carcinoma [44]. This evidence concerns the gene TGFB1 and cancer.