CD274 and non-small cell lung carcinoma: In NSCLC, PD‐1 on activated T cells binds PD‐L1 (on tumor or stromal cells), suppressing T‐cell proliferation, cytokine release, and cytotoxic function; antibodies targeting PD‐1 or PD‐L1 release this “brake,” restoring anti‐tumor T cell activity [8].