ENPP1 and neoplasm: To explore the hydrolytic capability of tumor exosomal ENPP1 to 2′3′‐cGAMP, a competition ELISA of 2′3′‐cGAMP assay was adopted (Figure 1F).[28] We used (1) A375‐, A549‐, and MDA‐MB‐231 cell‐derived exosomes (A375 EXOs, A549 EXOs, and MDA‐MB‐231 EXOs) with high expression of ENPP1 and (2) SW480 cell‐derived exosomes (SW480 EXOs) with relatively low expression of ENPP1 as models.