SIRPA and cancer: In addition, we found that macrophage subpopulations (clusters 1, 5, 7, 8, and 9) from cancer tissues expressed a certain number of immunosuppressive genes, such as VEGFA, MMP14, MMP19, S100A2, APOE, HMOX1, SLAMF7, SIRPα, LAG3 and IL18.