TGFB1 and gastric cancer: Therefore, we investigated the function of TGF-β1 in the production of IL-25 in GC tissue by examining freshly isolated monocytes and differentiated Mφs that had been cultured in the presence of recombinant human (rh) TGF-β1 or tumor culture supernatant (TSN) prepared from a gastric cancer cell line SGC7901.