In contrast, exposure to IL-4 and/or IL13 (24h) polarizes them towards pro-tumor M2-macrophage fate (aka tumor associated macrophages or TAMs) [39], as detected by increased expression of the M2-macrophage biomarkers; CCL17 and CCL18 in them (see RT/PCR analysis, Figure 7I lower). This evidence concerns the gene IL4 and neoplasm.