title: Pilocytic astrocytoma: a review of genetic and molecular factors, diagnostic and prognostic markers.
abstract: In spite of numerous studies concerning the pathogenesis of pilocytic astrocytoma (PA), the exact mechanism of the process still remains undetermined. It is difficult to obtain concordance between particular studies, which makes review of existing data especially troublesome. Nevertheless, the most important causative factors seem to be NF1 gene inactivation, in cases related to neurofibromatosis type 1, and BRAF gene overexpression in sporadic PAs, both resulting in MAPK/Erk pathway upregulation. Other molecular alterations, like mTOR or PI3K pathway deregulation, or Matrilin 2 overexpression, may influence the course of the disease, leading to the development of more aggressive and recurrent tumors. In the current paper we review genetic alterations in PA and describe currently studied molecular markers that may contribute to the development of the tumor and can be used in pathological staging of the malformation.
authors.affiliation: Department of Histology and Embryology, Center for Biostructure Research, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Bikowska-Opalach
authors.affiliation: Department of Histology and Embryology, Center for Biostructure Research, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Stanisław
authors.initials: S
authors.lastname: Szlufik
authors.affiliation: Department of Pathology, The Children's Memorial Health Institute, Warsaw, and Department of Experimental and Clinical Neuropathology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Poland.
authors.forename: Wiesława
authors.initials: W
authors.lastname: Grajkowska
authors.affiliation: Department of Histology and Embryology, Center for Biostructure Research, Medical University of Warsaw, Warsaw, Poland. jjozwiak@atdv.com.pl.
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Jozwiak
mesh_terms: D001254:Astrocytoma / Q000175:diagnosis* / Q000235:genetics* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000235:genetics*; D016543:Central Nervous System Neoplasms / Q000175:diagnosis* / Q000235:genetics* / Q000473:pathology; D003582:Cytogenetics; D006801:Humans; D011379:Prognosis
chemical_list: D014408:Biomarkers, Tumor