Electroporation of CCL22 siRNA into exosomes derived from PANC-02 cells induced by mitoxantrone (MTX), which can block the CCR4/CCL22 axis between DCs and Treg cells to inhibit the expansion of Treg cells, and intramuscular injection of exosomes containing CCL22 can delay the growth of pancreatic cancer, so it is expected to become an effective preventive vaccine (Zhou et al., 2022). Here, CCL22 is linked to pancreatic neoplasm.