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- Mangerel, Joshua, et al.
(author)
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Alternative lengthening of telomerases is enriched in, and impacts survival of TP53 mutant pediatric malignant brain tumors
- 2014
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In: Acta Neuropathologica. - : Springer Science and Business Media LLC. - 0001-6322 .- 1432-0533. ; 128:6, s. 853-862
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Journal article (peer-reviewed)abstract
- Although telomeres are maintained in most cancers by telomerase activation, a subset of tumors utilize alternative lengthening of telomeres (ALT) to sustain self-renewal capacity. In order to study the prevalence and significance of ALT in childhood brain tumors we screened 517 pediatric brain tumors using the novel C-circle assay. We examined the association of ALT with alterations in genes found to segregate with specific histological phenotypes and with clinical outcome. ALT was detected almost exclusively in malignant tumors (p = 0.001). ALT was highly enriched in primitive neuroectodermal tumors (12 %), choroid plexus carcinomas (23 %) and high-grade gliomas (22 %). Furthermore, in contrast to adult gliomas, pediatric low grade gliomas which progressed to high-grade tumors did not exhibit the ALT phenotype. Somatic but not germline TP53 mutations were highly associated with ALT (p = 1.01 × 10(-8)). Of the other alterations examined, only ATRX point mutations and reduced expression were associated with the ALT phenotype (p = 0.0005). Interestingly, ALT attenuated the poor outcome conferred by TP53 mutations in specific pediatric brain tumors. Due to very poor prognosis, one year overall survival was quantified in malignant gliomas, while in children with choroid plexus carcinoma, five year overall survival was investigated. For children with TP53 mutant malignant gliomas, one year overall survival was 63 ± 12 and 23 ± 10 % for ALT positive and negative tumors, respectively (p = 0.03), while for children with TP53 mutant choroid plexus carcinomas, 5 years overall survival was 67 ± 19 and 27 ± 13 % for ALT positive and negative tumors, respectively (p = 0.07). These observations suggest that the presence of ALT is limited to a specific group of childhood brain cancers which harbor somatic TP53 mutations and may influence the outcome of these patients. Analysis of ALT may contribute to risk stratification and targeted therapies to improve outcome for these children.
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- Perotti, Daniela, et al.
(author)
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Hallmark discoveries in the biology of Wilms tumour
- 2023
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In: Nature Reviews Urology. - 1759-4812.
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Research review (peer-reviewed)abstract
- The modern study of Wilms tumour was prompted nearly 50 years ago, when Alfred Knudson proposed the ‘two-hit’ model of tumour development. Since then, the efforts of researchers worldwide have substantially expanded our knowledge of Wilms tumour biology, including major advances in genetics — from cloning the first Wilms tumour gene to high-throughput studies that have revealed the genetic landscape of this tumour. These discoveries improve understanding of the embryonal origin of Wilms tumour, familial occurrences and associated syndromic conditions. Many efforts have been made to find and clinically apply prognostic biomarkers to Wilms tumour, for which outcomes are generally favourable, but treatment of some affected individuals remains challenging. Challenges are also posed by the intratumoural heterogeneity of biomarkers. Furthermore, preclinical models of Wilms tumour, from cell lines to organoid cultures, have evolved. Despite these many achievements, much still remains to be discovered: further molecular understanding of relapse in Wilms tumour and of the multiple origins of bilateral Wilms tumour are two examples of areas under active investigation. International collaboration, especially when large tumour series are required to obtain robust data, will help to answer some of the remaining unresolved questions.
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