Primary tumor cells derived from two models of murine medulloblastoma (Ptch1(+/-);Ink4c(-/-) and p53(FL/FL);Nestin-Cre(+); Ink4c(-/-)) that retain and lack p53 function, respectively, displayed a dependence on functional p53 to engage 17-DMAG-induced apoptosis.
In mice, Ptc1 haploinsufficiency and disruption of DNA repair (DNA ligase IV inactivation) or cell cycle regulation (Kip1, Ink4d, or Ink4c inactivation), in conjunction with p53 dysfunction, predispose to medulloblastoma.