Freshly isolated monocytes were differentiated into MDM with M-CSF before polarization into M1 using IFN-γ and LPS or into M2 macrophages by IL-4 and IL-13, or were co-cultured with NCI-H460 or MCF-7 tumour cells to better mimic a realistic situation of macrophage polarization by tumours. The gene discussed is CSF1; the disease is neoplasm.