Chromosome 17p deletion in human medulloblastoma: a missing checkpoint in the Hedgehog pathway.
Although deregulation of Hedgehog signalling is considered to play a crucial oncogenic role and commonly occurrs in medulloblastoma, genetic lesions in components of this pathway are observed in a minority of cases. The recent identification of a novel putative tumor suppressor (REN(KCTD11)) on chromosome 17p13.2, a region most frequently lost in human medulloblastoma, highlights the role of allelic deletion of the gene in this brain malignancy, leading to the loss of growth inhibitory activity via suppression of Gli-dependent activation of Hedgehog target genes. The presence on 17p13 of another tumor suppressor gene (p53) whose inactivation cooperates with Hedgehog pathway for medulloblastoma formation, suggests that 17p deletion unveils haploinsufficiency conditions leading to abrogation of either direct and indirect checkpoints of Hedgehog signalling in cancer.
Department of Experimental Medicine and Pathology, University La Sapienza, Rome, Italy.
Enrico
E
De Smaele
Lucia
L
Di Marcotullio
Elisabetta
E
Ferretti
Isabella
I
Screpanti
Edoardo
E
Alesse
Alberto
A
Gulino
D002528:Cerebellar Neoplasms / Q000235:genetics*; D002872:Chromosome Deletion; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D053823:Hedgehog Proteins; D006801:Humans; D008527:Medulloblastoma / Q000235:genetics*; D009154:Mutation / Q000235:genetics; D015534:Trans-Activators / Q000378:metabolism*
D053823:Hedgehog Proteins; D015534:Trans-Activators