A central immunosuppressive cytokine, almost constantly involved in cancer immunosuppression regardless of the type of neoplasm, is transforming growth factor β (TGF-β), whose activities exert mainly via the SMAD2 and SMAD3 transcription factors (and their regulation) to induce suppression of inflammatory cytokines’ transcription and polarization of naïve T cells towards the Treg phenotype [14,17,19,26,27]. The gene discussed is TGFB1; the disease is neoplasm.