Of note, SMAD3 is known as a key molecule in TGF-β signaling pathway and studies have shown the inhibitory effect of SMAD3 and the TGF-β pathway on natural killer cells in the tumor microenvironment: disruption of SMAD3 in natural killer cells was associated with enhanced activity of natural killer cells and cytokine production [38]. The gene discussed is SMAD3; the disease is neoplasm.