This TGF-β produced by tumor cells appeared to be biologically active, acting in an autocrine loop on tumor cells, since we observed induction of a TGF-β target gene (Serpin1) 24 hours and 48 hours after CDDP treatment in 4T1 (Figure 4D) and EMT6 (Supplemental Figure 4, B and C) tumors. Here, TGFB1 is linked to neoplasm.