To investigate the function of TGF-β in the UDCA-mediated reduction in Treg cells, we administered UDCA and found that it did not inhibit tumor growth in LLC tumor-bearing mice with TGF-βRII deficiency (Tgfbr2f/fEr-cre, treated with tamoxifen) (Fig. 1g). This evidence concerns the gene TGFB1 and neoplasm.