The results showed that, although GM-CSF stimulation did not affect cell viability, GM-CSF-educated cancer cells were resistant obviously to fluorouracil (5-FU), oxiliplatin or irinotecan-mediated cell death, by SRB assays (Fig. 4a and S8a) and Annexin V/PI analysis (Fig. 4b and S8b). Here, CSF2 is linked to cancer.