Therefore, in this work, we screened normal tissue and metastatic cancer datasets for expression of Notch ligands (DLL1, DLL3, DLK1, JAG1, JAG2) and uncovered DLK1 (delta-like non-canonical Notch ligand 1) as a candidate cell surface immunotherapy target protein. The gene discussed is DLK1; the disease is metastatic malignant neoplasm.