Because previous studies reported that the TGF-β pathway was a core pathway that inhibits NK cell and T cell activities, we paid special attention to this pathway and found that Tgfb1, a key ligand initiating the TGF-β pathway, was downregulated in all types of peripheral immune cells when the tumor burden increased and OH2 was further injected (Figure 1H). This evidence concerns the gene TGFB1 and neoplasm.