VSIR and soft tissue sarcoma: In soft tissue sarcoma, the results of IHC shows that VISTA is highly accumulated on the membrane and cytoplasm of tumor cells, and positively associated with the expression of PD1 and PD-L1 [25], higher expression of PD1 is proved within sarcoma cells [57] and higher PD-L1 membrane expression is mainly found on tumor-infiltrating myeloid cells [58], especially on macrophages, these three immune checkpoints are involved in the regulation of tumor immunosuppression.