assertion retraction graph subject predicate object datatype annotation 1 0 graph DOID:4439 IAO:0000115 A central nervous system cancer that is characterized by tumors near the pineal gland, the pituitary gland and the tissue just above it, develops from mismigrational pluripotent embryonic cells that remain in the brain after birth, has_material_basis_in abnormally proliferating cells derives_from germ cells. xsd:string "{""dce:type"":[{""datatype"":""_IRI"",""meta"":""owl:Axiom"",""object"":""obo:ECO_0007645""}],""oio:hasDbXref"":[{""datatype"":""xsd:string"",""meta"":""owl:Axiom"",""object"":""url:https://www.ncbi.nlm.nih.gov/pubmed/25233069""}]}"