CCL21 and familial pancreatic carcinoma: Previous studies have indicated that CCL19, CCL21, CCL24, CCL25, CXCL8, and CXCL2 specifically induce macrophage polarization towards the M1 phenotype, while CCL7 facilitates polarization towards both M1 and M2 phenotypes [45]; nevertheless, the mechanism by which CXCL10 induces the polarization of macrophages towards the M2 phenotype in the context of pancreatic cancer has not yet been elucidated.