EGFR and osteosarcoma: In contrast, IL-10–stimulated M2-like macrophages failed to inhibit cell growth of (or form cell conjugates with) cetuximab-coated OHS cells despite high levels of EGFR expression[31], indicating that additional cell characteristics play a role in determining the sensitivity of osteosarcoma cell lines to antibody-dependent anti-tumor activity (Figure 5, panel D and data not shown).