Cells with TP53 mutations in low grade astrocytic tumors evolve clonally to malignancy and are an unfavorable prognostic factor. - Ishii,N.; Tada,M.; Hamou,M.F.; Janzer,R.C.; Meagher-Villemure,K.; Wiestler,O.D.; Tribolet,N.; Van Meir,E.G. (Oncogene, 1999)