SMAD5 and breast cancer: Moreover, lncRNA SNHG16 transmitted by exosomes is also proved to induce CD73+γδ1 Treg in breast cancer by sponging miR-16-4p, which enables the downregulation of SMAD5, the subsequent enhancement of TGF-b1/SMAD5 pathway, and finally, the promotion of CD73 expression [30].