CD274 and neoplasm: These include: (a) regulatory T cells (Treg) (Fig. 5a, b), as demonstrated by the higher effector/Treg ratio (**P < 0.005 vs control, *P < 0.05 vs TUSC2); (b) PD1+ T cells (CD3+CD274+ T, CD4+CD274+ T, CD8+CD274+ T) (Fig. 5c); (c) myeloid-derived suppressor cells (MDSC) (Fig. 5d); and (d) M2 tumor associated macrophages (TAMs), (Fig. 5e) These results indicate that the triple combination diminishes the immunosuppressive TME, mediated largely by tumor-infiltrating MDSCs, TAMs and Tregs, significantly more than TUSC2 plus pembrolizumab or carboplatin plus pembrolizumab.