In tumor-bearing mice two functionally distinct subtypes of MDSCs have been identified: CD11b+Ly6G+Ly6Clow MDSCs which are morphologically similar to polymorphonuclear granulocytes (grMDSCs) and CD11b+Ly6G−Ly6Chigh MDSCs which have a monocytic phenotype (moMDSCs). Here, ITGAM is linked to neoplasm.