Interestingly, blunting NF-kB signaling by inhibition of its upstream activator IκB kinase (IKK) in human melanoma (SK-MEL-28) and pancreatic adenocarcinoma (Panc1) on doxorubicin treatment of senescent cells resulted in a marked decrease of PD-L2 mRNA levels while PD-L1 expression was largely unaffected (Fig. 1f and Extended Data Fig. 1g). This evidence concerns the gene CD274 and melanoma.