For the polarization induced by PDAC-CM, given the complex composition of cytokines secreted by tumor cells, we noticed that CSF1 plays a key role in inducing the M2 polarization of macrophages in PDAC (Zhu et al., 2014) and CSF1 mRNA was highly expressed in PANC-1 and PANC-02 cells. This evidence concerns the gene CSF1 and neoplasm.