Chang et al. found that miR-21-5p levels in exosomes derived from TAMs were down-regulated in pancreatic cancer, inhibiting Nanog/Oct4 expression, and targeting Krüppel-like factor 3 (KLF3) decreased, thereby inhibiting CSC activity in pancreatic cancer [97]. The gene discussed is KLF3; the disease is familial pancreatic carcinoma.