PTEN and pachyonychia congenita: Recent research indicated that hypoxic exosomes derived from pancreatic cancer cells could activate the phosphatase and tensin homolog (PTEN)/phosphorinositol 3-kinase (PI3K) gamma signaling pathway, followed by stimulating macrophages to the M2 phenotype in a hypoxia inducible factor 1 or 2 subunit alpha (HIF1a or HIF2a)-dependent way, which facilitates the invasion, migration and epithelial-mesenchymal transition (EMT) of PC cells.