Fan J et al. isolated Pex from three PaCa cell lines that showed resistance to gemcitabine and reported that expression of exosome EphA2 could convey chemoresistance and predicted that it might be a powerful surface biomarker of exosomes [57, 81–83]. This evidence concerns the gene EPHA2 and permanent neonatal diabetes mellitus-pancreatic and cerebellar agenesis syndrome.