CSF2 and cancer: In order to further evaluate whether ExoGM‐CSF could transfer the mRNA to the recipient cells and in turn produce GM‐CSF protein, recipient cells were treated with ExoGM‐CSF, the control ExoNone (Exosomes from cancer cells with no additional treatment), or ExoCtrl, and 24 h later cell‐free supernatants were collected for analysis of the level of GM‐CSF using enzyme‐linked immunosorbent assay (ELISA) assay (Figure 2G).