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Clinical implications of PIK3CA mutations in gliomas molecular subgroups

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Resumo:Gliomas are the most common and lethal malignant tumors of central nervous system. In 2016, World Health Organization (WHO) classification included IDH mutations and 1p/19q codeletion as a diagnostic criteria to define gliomas. However new biomarkers of diagnosis, prognosis and response to therapy are needed. In this context, PIK3CA mutations have been described as constitutive mutations seeming to be a good therapeutic target. Our objective was to clarify the clinical importance of PIK3CA mutations according to the 2016 WHO classification, as well as the impact of several biomarkers on diagnosis, prognosis and response to therapy in 437 glioma samples. According to the multivariate analysis performed, gliomas molecular subgroups have higher prognostic value than histological subgroups (P<0.001). PTEN deletions were considered prognostic factors of poor outcomes in astrocytomas IDH wildtype, while in GBM IDH wildtype were associated with better prognosis. On opposite, EGFR amplification and TERT mutations had no impact in the overall survival of patients. We verified that EGFR amplification had a predictive value of response to radiotherapy (P=0.007). PIK3CA mutations were most common in IDH mutant + 1p/19q codeletion (oligodendrogliomas) (10%). H1047R and E542K were the most frequent mutations identified in the remaining gliomas molecular subgroups. Importantly, we found 3 unreported pathogenic variants in exon 20 of PIK3CA (c.3112T>C, c.2988T>C, c.3040C>T) and one polymorphic variant (c.3210A>G). For the first time, it was identified the rs45455192 polymorphism (16% - 24%) in the different gliomas molecular subgroups, although this polymorphism did not showed prognostic value. The recurrences analysis demonstrated that PIK3CA mutations constitute early events maintained during tumor progression. Overall, this study showed molecular classification is a more accurate method to predict clinical outcome and despite PIK3CA mutations being present at low frequency in gliomas, they seem to be important for tumor progression.
Autores principais:Brito, Cheila Martins
Assunto:Gliomas PIK3CA mutations 2016 WHO classification therapeutic target
Ano:2018
País:Portugal
Tipo de documento:dissertação de mestrado
Tipo de acesso:acesso aberto
Instituição associada:Universidade Nova de Lisboa
Idioma:inglês
Origem:Repositório Institucional da UNL
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author Brito, Cheila Martins
author_facet Brito, Cheila Martins
author_role author
contributor_name_str_mv Sousa, Marta
Roque, Maria Lúcia
RUN
country_str PT
creators_json_txt [{\"Person.name\":\"Brito, Cheila Martins\"}]
datacite.contributors.contributor.contributorName.fl_str_mv Sousa, Marta
Roque, Maria Lúcia
RUN
datacite.creators.creator.creatorName.fl_str_mv Brito, Cheila Martins
datacite.date.Accepted.fl_str_mv 2018-11-01T00:00:00Z
datacite.date.available.fl_str_mv 2019-01-21T13:52:46Z
datacite.date.embargoed.fl_str_mv 2019-01-21T13:52:46Z
datacite.rights.fl_str_mv http://purl.org/coar/access_right/c_abf2
datacite.subjects.subject.fl_str_mv Gliomas
PIK3CA
mutations
2016 WHO classification
therapeutic target
datacite.titles.title.fl_str_mv Clinical implications of PIK3CA mutations in gliomas molecular subgroups
dc.contributor.none.fl_str_mv Sousa, Marta
Roque, Maria Lúcia
RUN
dc.creator.none.fl_str_mv Brito, Cheila Martins
dc.date.Accepted.fl_str_mv 2018-11-01T00:00:00Z
dc.date.available.fl_str_mv 2019-01-21T13:52:46Z
dc.date.embargoed.fl_str_mv 2019-01-21T13:52:46Z
dc.format.none.fl_str_mv application/pdf
dc.identifier.none.fl_str_mv http://hdl.handle.net/10362/58097
dc.language.none.fl_str_mv eng
dc.rights.none.fl_str_mv http://purl.org/coar/access_right/c_abf2
dc.subject.none.fl_str_mv Gliomas
PIK3CA
mutations
2016 WHO classification
therapeutic target
dc.title.fl_str_mv Clinical implications of PIK3CA mutations in gliomas molecular subgroups
dc.type.none.fl_str_mv http://purl.org/coar/resource_type/c_bdcc
description Gliomas are the most common and lethal malignant tumors of central nervous system. In 2016, World Health Organization (WHO) classification included IDH mutations and 1p/19q codeletion as a diagnostic criteria to define gliomas. However new biomarkers of diagnosis, prognosis and response to therapy are needed. In this context, PIK3CA mutations have been described as constitutive mutations seeming to be a good therapeutic target. Our objective was to clarify the clinical importance of PIK3CA mutations according to the 2016 WHO classification, as well as the impact of several biomarkers on diagnosis, prognosis and response to therapy in 437 glioma samples. According to the multivariate analysis performed, gliomas molecular subgroups have higher prognostic value than histological subgroups (P<0.001). PTEN deletions were considered prognostic factors of poor outcomes in astrocytomas IDH wildtype, while in GBM IDH wildtype were associated with better prognosis. On opposite, EGFR amplification and TERT mutations had no impact in the overall survival of patients. We verified that EGFR amplification had a predictive value of response to radiotherapy (P=0.007). PIK3CA mutations were most common in IDH mutant + 1p/19q codeletion (oligodendrogliomas) (10%). H1047R and E542K were the most frequent mutations identified in the remaining gliomas molecular subgroups. Importantly, we found 3 unreported pathogenic variants in exon 20 of PIK3CA (c.3112T>C, c.2988T>C, c.3040C>T) and one polymorphic variant (c.3210A>G). For the first time, it was identified the rs45455192 polymorphism (16% - 24%) in the different gliomas molecular subgroups, although this polymorphism did not showed prognostic value. The recurrences analysis demonstrated that PIK3CA mutations constitute early events maintained during tumor progression. Overall, this study showed molecular classification is a more accurate method to predict clinical outcome and despite PIK3CA mutations being present at low frequency in gliomas, they seem to be important for tumor progression.
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person_str_mv Brito, Cheila Martins
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spelling engpt_PTGliomas are the most common and lethal malignant tumors of central nervous system. In 2016, World Health Organization (WHO) classification included IDH mutations and 1p/19q codeletion as a diagnostic criteria to define gliomas. However new biomarkers of diagnosis, prognosis and response to therapy are needed. In this context, PIK3CA mutations have been described as constitutive mutations seeming to be a good therapeutic target. Our objective was to clarify the clinical importance of PIK3CA mutations according to the 2016 WHO classification, as well as the impact of several biomarkers on diagnosis, prognosis and response to therapy in 437 glioma samples. According to the multivariate analysis performed, gliomas molecular subgroups have higher prognostic value than histological subgroups (P<0.001). PTEN deletions were considered prognostic factors of poor outcomes in astrocytomas IDH wildtype, while in GBM IDH wildtype were associated with better prognosis. On opposite, EGFR amplification and TERT mutations had no impact in the overall survival of patients. We verified that EGFR amplification had a predictive value of response to radiotherapy (P=0.007). PIK3CA mutations were most common in IDH mutant + 1p/19q codeletion (oligodendrogliomas) (10%). H1047R and E542K were the most frequent mutations identified in the remaining gliomas molecular subgroups. Importantly, we found 3 unreported pathogenic variants in exon 20 of PIK3CA (c.3112T>C, c.2988T>C, c.3040C>T) and one polymorphic variant (c.3210A>G). For the first time, it was identified the rs45455192 polymorphism (16% - 24%) in the different gliomas molecular subgroups, although this polymorphism did not showed prognostic value. The recurrences analysis demonstrated that PIK3CA mutations constitute early events maintained during tumor progression. Overall, this study showed molecular classification is a more accurate method to predict clinical outcome and despite PIK3CA mutations being present at low frequency in gliomas, they seem to be important for tumor progression.application/pdfpt_PTClinical implications of PIK3CA mutations in gliomas molecular subgroupsBrito, Cheila MartinsSousa, MartaRoque, Maria LúciaHostingInstitutionOrganizationalRUNe-mailmailto:run@unl.ptrun@unl.pt2019-01-21T13:52:46Z2018-1120182018-11-01T00:00:00ZHandlehttp://hdl.handle.net/10362/58097http://purl.org/coar/access_right/c_abf2open accessGliomasPIK3CAmutations2016 WHO classificationtherapeutic target2207759 bytesliteraturehttp://purl.org/coar/resource_type/c_bdccmaster thesishttp://purl.org/coar/access_right/c_abf2application/pdffulltexthttps://run.unl.pt/bitstreams/e67a4dee-1651-4dce-bbc6-13ef7d5a5649/download
spellingShingle Clinical implications of PIK3CA mutations in gliomas molecular subgroups
Brito, Cheila Martins
Gliomas
PIK3CA
mutations
2016 WHO classification
therapeutic target
status SINGLETON
subject.fl_str_mv Gliomas
PIK3CA
mutations
2016 WHO classification
therapeutic target
title Clinical implications of PIK3CA mutations in gliomas molecular subgroups
title_full Clinical implications of PIK3CA mutations in gliomas molecular subgroups
title_fullStr Clinical implications of PIK3CA mutations in gliomas molecular subgroups
title_full_unstemmed Clinical implications of PIK3CA mutations in gliomas molecular subgroups
title_short Clinical implications of PIK3CA mutations in gliomas molecular subgroups
title_sort Clinical implications of PIK3CA mutations in gliomas molecular subgroups
topic Gliomas
PIK3CA
mutations
2016 WHO classification
therapeutic target
topic_facet Gliomas
PIK3CA
mutations
2016 WHO classification
therapeutic target
url http://hdl.handle.net/10362/58097
visible 1