By isolating Epcam+ cancer cells, F4/80+ macrophages, and GFP+ MAFs through flow cytometry-based cell sorting from metastasis-bearing Pdgfrb-GFP mice, we confirmed that, in agreement with previous reports22, tumour-associated macrophages were the main source of progranulin (Grn) (Fig. 5J), whereas cancer cells were the main source of Lif transcripts (Fig. 5K). This evidence concerns the gene LIF and cancer.