For example, VPA affected the expression of P-glycoprotein (ABCB1) in tumor cell lines and in rat livers (Eyal et al., 2006; Hauswald et al., 2009) and that of folate receptor α (FRα; FOLR1) in pregnant mice (Meir et al., 2016) and in a human placental cell line (Rubinchik-Stern et al., 2015). Here, FOLR1 is linked to neoplasm.