In the tumor microenvironment, myeloid‐derived suppressor cells (MDSCs) and regulatory T cells (Tregs) promote tumor immune escape through the release of immunosuppressive factors, while activated MDSCs and Tregs express large amounts of PD‐L1, which interacts with PD‐1 on T cells and can also lead to T cell exhaustion.[54, 55] Next, we performed a flow cytometric analysis of tumor tissue. Here, CD274 is linked to neoplasm.