Pro-inflammatory cytokines relevant to pulmonary oncology intersect with checkpoint pathways: IL-6 trans-activates JAK/STAT3 in lung cancer and can upregulate PD-L1, while EGFR signaling on tumor cells converges on the IL-6–STAT3 axis to enhance PD-L1 expression [98,99]. Here, CD274 is linked to lung carcinoma.