A recent publication by Noh et al. revealed that co-culture of PD-L1-expressing B16F10 melanoma cells with bone marrow-derived cells results in a smaller proportion of cells undergoing apoptosis/necrosis following gemcitabine treatment [14]; however that study did not assess the contribution of the PD-1/PD-L1 axis specifically. Here, CD274 is linked to melanoma.