FCGR2B and cancer: Our results demonstrated that the expression levels of all of the cell surface FcγRs, including activating FcγRs (FcgRI, FcgRIII, and FcgRIV) and inhibitory FcγRs (FcgRIIB) [71], remained unchanged following 24 h of rapamycin pretreatment (Figure 3B), suggesting that rapamycin does not impair macrophages’ ability to recognize and bind to antibody-coated cancer cells.