BST2 and colorectal carcinoma: The representative image of immunohistochemistry (IHC) results of 40 cases of CRC clinical specimens showed that high expression of BST2 expression tended to be associated with the infiltration of more M2 macrophages (CD163 positive) instead of lymphocytes (CD3 positive) and myeloid-derived suppressor cells (MDSCs) (CD33 positive) (Figure 6A-B).