PTEN Signaling in the Postnatal Perivascular Progenitor Niche Drives Medulloblastoma Formation.
Loss of the tumor suppressor gene PTEN exerts diverse outcomes on cancer in different developmental contexts. To gain insight into the effect of its loss on outcomes in the brain, we conditionally inactivated the murine Pten gene in neonatal neural stem/progenitor cells. Pten inactivation created an abnormal perivascular proliferative niche in the cerebellum that persisted in adult animals but did not progress to malignancy. Proliferating cells showed undifferentiated morphology and expressed the progenitor marker Nestin but not Math1, a marker of committed granule neuron progenitors. Codeletion of Pten and Trp53 resulted in fully penetrant medulloblastoma originating from the perivascular niche, which exhibited abnormal blood vessel networks and advanced neuronal differentiation of tumor cells. EdU pulse-chase experiments demonstrated a perivascular cancer stem cell population in Pten/Trp53 double mutant medulloblastomas. Genetic analyses revealed recurrent somatic inactivations of the tumor suppressor gene Ptch1 and a recapitulation of the sonic hedgehog subgroup of human medulloblastomas. Overall, our results showed that PTEN acts to prevent the proliferation of a progenitor niche in postnatal cerebellum predisposed to oncogenic induction of medulloblastoma. Cancer Res; 77(1); 123-33. ©2016 AACR.
Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee.|Integrated Program in Biomedical Sciences, The University of Tennessee Health Science Center, Memphis, Tennessee.
Guo
G
Zhu
Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee.
Sherri L
SL
Rankin
Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee.
Jon D
JD
Larson
Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee.
Xiaoyan
X
Zhu
Division of Oncology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
Lionel M L
LM
Chow
Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee.
Chunxu
C
Qu
Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee.
Jinghui
J
Zhang
Department of Pathology, St. Jude Children's Research Hospital, Memphis, Tennessee.
David W
DW
Ellison
Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee. suzanne.baker@stjude.org.|Integrated Program in Biomedical Sciences, The University of Tennessee Health Science Center, Memphis, Tennessee.
Suzanne J
SJ
Baker
D000818:Animals; D002528:Cerebellar Neoplasms / Q000235:genetics* / Q000473:pathology; D055028:Comparative Genomic Hybridization; D004195:Disease Models, Animal; D005455:Fluorescent Antibody Technique; D007150:Immunohistochemistry; D008527:Medulloblastoma / Q000235:genetics* / Q000473:pathology; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D014411:Neoplastic Stem Cells / Q000473:pathology*; D058953:Neural Stem Cells / Q000473:pathology*; D020411:Oligonucleotide Array Sequence Analysis; D051059:PTEN Phosphohydrolase / Q000235:genetics*; D016133:Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology; D055153:Stem Cell Niche / Q000502:physiology; D016159:Tumor Suppressor Protein p53 / Q000235:genetics
D016159:Tumor Suppressor Protein p53; D051059:PTEN Phosphohydrolase; C487757:Pten protein, mouse