JAG2 and colorectal cancer: When JAG2 was overexpressed in colorectal cancer cell line HT29, PRAF2 was up-regulated (Fig. 7a), then the number of exosomes secreted by colorectal cancer cells was significantly increased (Fig. 7b) and the level of JAG2 and PRAF2 proteins in exosomes was upregulated (Fig. 7c).