PURPOSE: Identifying pathobiological correlates of clinical behavior or therapeutic response currently represents a key challenge for medulloblastoma research. Nuclear accumulation of the beta-catenin protein is associated with activation of the Wnt/Wg signaling pathway, and mutations affecting components of this pathway have been reported in approximately 15% of sporadic medulloblastomas. We tested the hypothesis that nuclear immunoreactivity for beta-catenin is a prognostic marker in medulloblastoma, and assessed the relationship between nuclear beta-catenin immunoreactivity and mutations of CTNNB1 and APC. PATIENTS AND METHODS: Medulloblastomas from children entered onto the International Society for Pediatric Oncology (SIOP)/United Kingdom Children's Cancer Study Group (UKCCSG) PNET3 trial (n = 109) were examined for beta-catenin immunoreactivity, and where tissue was available, evidence of CTNNB1 and APC mutations. The results were correlated with clinicopathologic variables, principally outcome. RESULTS: Children with medulloblastomas that showed a nucleopositive beta-catenin immunophenotype (27 of 109; 25%) had significantly better overall (OS) and event-free (EFS) survivals than children with tumors that showed either membranous/cytoplasmic beta-catenin immunoreactivity or no immunoreactivity (P = .0015 and P = .0026, respectively). For beta-catenin nucleopositive and nucleonegative medulloblastomas, 5-year OS was 92.3% (95% CI, 82% to 100%) versus 65.3% (95% CI, 54.8 to 75.7%), and 5-year EFS was 88.9% (95% CI, 77% to 100%) versus 59.5% (95% CI, 48.8 to 70.2%), respectively. Mutations in CTNNB1 were found exclusively among medulloblastomas that demonstrated nuclear beta-catenin immunoreactivity, but no evidence of APC mutation was found in these cases. All children with beta-catenin nucleopositive large cell/anaplastic medulloblastomas and beta-catenin nucleopositive medulloblastomas presenting with metastatic disease are alive at least 5 years postdiagnosis. CONCLUSION: Nuclear accumulation of beta-catenin appears to be a marker of favorable outcome in medulloblastoma, and should be investigated further in large group-wide trials.
PURPOSE: Identifying pathobiological correlates of clinical behavior or therapeutic response currently represents a key challenge for medulloblastoma research. Nuclear accumulation of the beta-catenin protein is associated with activation of the Wnt/Wg signaling pathway, and mutations affecting components of this pathway have been reported in approximately 15% of sporadic medulloblastomas. We tested the hypothesis that nuclear immunoreactivity for beta-catenin is a prognostic marker in medulloblastoma, and assessed the relationship between nuclear beta-catenin immunoreactivity and mutations of CTNNB1 and APC. PATIENTS AND METHODS: Medulloblastomas from children entered onto the International Society for Pediatric Oncology (SIOP)/United Kingdom Children's Cancer Study Group (UKCCSG) PNET3 trial (n = 109) were examined for beta-catenin immunoreactivity, and where tissue was available, evidence of CTNNB1 and APC mutations. The results were correlated with clinicopathologic variables, principally outcome. RESULTS:Children with medulloblastomas that showed a nucleopositive beta-catenin immunophenotype (27 of 109; 25%) had significantly better overall (OS) and event-free (EFS) survivals than children with tumors that showed either membranous/cytoplasmic beta-catenin immunoreactivity or no immunoreactivity (P = .0015 and P = .0026, respectively). For beta-catenin nucleopositive and nucleonegative medulloblastomas, 5-year OS was 92.3% (95% CI, 82% to 100%) versus 65.3% (95% CI, 54.8 to 75.7%), and 5-year EFS was 88.9% (95% CI, 77% to 100%) versus 59.5% (95% CI, 48.8 to 70.2%), respectively. Mutations in CTNNB1 were found exclusively among medulloblastomas that demonstrated nuclear beta-catenin immunoreactivity, but no evidence of APC mutation was found in these cases. All children with beta-catenin nucleopositive large cell/anaplastic medulloblastomas and beta-catenin nucleopositive medulloblastomas presenting with metastatic disease are alive at least 5 years postdiagnosis. CONCLUSION: Nuclear accumulation of beta-catenin appears to be a marker of favorable outcome in medulloblastoma, and should be investigated further in large group-wide trials.
Authors: David W Ellison; Mehmet Kocak; James Dalton; Hisham Megahed; Meryl E Lusher; Sarra L Ryan; Wei Zhao; Sarah Leigh Nicholson; Roger E Taylor; Simon Bailey; Steven C Clifford Journal: J Clin Oncol Date: 2010-10-04 Impact factor: 44.544
Authors: Amar Gajjar; Roger J Packer; N K Foreman; Kenneth Cohen; Daphne Haas-Kogan; Thomas E Merchant Journal: Pediatr Blood Cancer Date: 2012-12-19 Impact factor: 3.167
Authors: Jennifer A Anderton; Janet C Lindsey; Meryl E Lusher; Richard J Gilbertson; Simon Bailey; David W Ellison; Steven C Clifford Journal: Neuro Oncol Date: 2008-07-29 Impact factor: 12.300