Given the observed improvement in tumor growth control by supplementing ADU-S100-based immunotherapy with anti-PD-L1 antibody in the B16 melanoma model, and by combining ARG2i + COX2i + NOS2i with ADU-S100 in the BPR20 melanoma model, we next evaluated correlative changes in the therapeutic TME in both systems. Here, CD274 is linked to melanoma.