PDX1 and teratoma: For examples, Ware et al. demonstrated that NSCs (naïve human ESCs) inclined to differentiate into endodermal lineage, as demonstrated by the expression of liver-specific lineage markers (i.e., albumin, α-fetoprotein, and E-cadherin) and pancreas-specific lineage markers (PDX1, SOX9, and E-cadherin), when they were forced to form solid tumors (teratomas) in vivo [34].