In vitro studies also suggested that sevoflurane-stimulated tumor cells exhibited higher level of phosphatase and tensin homologue (PTEN) and inactivation of phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) signaling pathway (25, 27), a crucial signaling in tumorigenesis (65). This evidence concerns the gene AKT1 and neoplasm.