PAX3 and neoplasm: In summary, here we revealed several novel tumor characterization and molecular mechanisms: (1) PAX3 expression is elevated in high-grade gliomas and BGSCs derived from GBM; (2) PAX3 is essential for the growth of BGSCs both in vitro and in vivo; (3) PAX3 and p53 expression in BGSCs is mutually-exclusive and PAX3 negatively regulates p53 action on BGSCs; (4) PAX3 transcriptionally represses p53 expression in BGSCs and differentiation; (5) hypoxia increases the expression of HIF-1α and PAX3 in differentiated BGSCs while reduces p53 expression.