Since macrophage subtypes are differentiated into M1 macrophages (identified as CD68+ CD163- HO-1- macrophages), M2 macrophages (CD68+ CD163+ HO-1-) and Mox macrophages (CD68+ CD163+ HO-1+), triple IHC was performed in lung tissue adjacent to the cancer margin to observe NRP-1 expression in single CD68+ AMs. Here, CD68 is linked to cancer.