SMAD9 and neoplasm: Comparison of the RNA levels of TGF-β signaling regulators in EC and noncancer samples showed that RNA levels of ZFYVE9, BMPR1B, TGFB3, TGFBRAP1, ACVRL1, TGFBR2, SMAD4, SMAD7, ACVR2A, BMPR1A, SMAD9, and TGFBR3 were significantly downregulated in EC tumor samples compared to normal samples; however, ACVR1 and SMAD1 were upregulated in EC samples (Figure 4).