CD274 and small cell lung carcinoma: In a study involving postoperative patients with SCLC treated with platinum and etoposide plus anti-programmed cell death ligand 1 antibody, it was observed that SCLC with high DLL3 expression developed resistance to immunochemotherapy due to tumor immunosuppression, despite having a higher load of neoantigens.148 Functionally, DLL3 acts as a regulator of cell-cell interactions in the neuroendocrine state of SCLC.149 Numerous preclinical and clinical studies targeting DLL3 are underway, defining it as a promising treatment strategy for SCLC.150,151