Furthermore, helper‐dependent adenoviruses that express PD‐L1 inhibitors could improve the anti‐tumor impact of oncolytic immunotherapy utilizing engineered adenovirus‐loaded mesenchymal stromal cells, resulting in the reduced tumor progression in an orthotopic lung cancer mouse models.[134] To summarize, immune checkpoint blockade is effective for facilitating anti‐tumor efficacy of different cancer immunotherapy using cell‐based delivery techniques to overcome overexpression of immunosuppressive ligands. Here, CD274 is linked to neoplasm.