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Background Embryonic stem cell markers, such as SOX2, NANOG, and OCT4, are transcription factors expressed in pluripotent stem cells, involved in the mediation of pluripotency and self-renewal. Especially after the discovery of cancer stem cells, these proteins have been associated with several types of neoplasia, including astrocytomas. In the pediatric population, astrocytomas are the most common solid neoplasia and present the highest mortality rates. Methods Our study evaluated 5 polymorphisms in SOX2, NANOG, and POU5F1 genes in 101 pediatric astrocytoma samples. Results We describe the associations between wild and polymorphic alleles in astrocytomas. Conclusions In our results, the intronic polymorphic G allele in SOX2 rs77677339 [G/A] had a borderline association with low-grade astrocytomas, and the intronic polymorphic T allele in NANOG rs10845877 [C/T] showed a higher frequency in grade 2, compared to grade 1 astrocytomas, thus showing promising results. Impact Our study is relevant because it shows a potential correlation between polymorphic embryonic stem cell marker genes and pediatric astrocytomas.

INTRODUÇÃO: Agenesia de dentes do grupamento anterossuperior é de fácil percepção por afetar a estética do sorriso, sendo esse o motivo principal da busca por tratamento nesses casos. A avaliação do sorriso deve abranger diversos aspectos desde a composição facial até características morfológicas dos elementos dentários e, dessa forma, se qualquer um desses aspectos forem afetados, o sorriso se torna esteticamente inadequado. Os novos tempos pedem padrões cada vez mais claros de sorrisos, inclusive as indústrias de resinas compostas criam cores mais claras devido a solicitação dos pacientes. Com isso o sorriso tem um valor extraordinário na sociedade, sendo ele um importante meio de comunicação e aceitação do indivíduo. METODOLOGIA: Trata-se de uma revisão de literatura baseada no uso do recontorno cosmético em dentes anteriores com resina composta, para correções de imperfeições estéticas. CONCLUSÃO: Mas quando a estética está comprometida, correções com faceta direta em resina composta, pela técnica de estratificação podem oferecer ao dente uma perfeita restauração, proporcionando beleza natural, estética, cor, anatomia, função e ainda sendo de baixo custo, não necessitando de desgastes de tecidos hígidos.

Central nervous system tumors, especially astrocytomas, are the solid neoplasms with the highest incidence and mortality rates in childhood. The diagnosis is based on histopathological characteristics, but molecular methods have been increasingly used. Translationally controlled tumor protein (TCTP) protein, encoded by the tumor protein, translationally controlled 1 ( TPT1) gene, is a multifunctional protein with an important physiological role in the cell cycle. Expression of this protein has been associated with several neoplasms, including astrocytomas in adults. However, the role of this protein in pediatric astrocytomas is largely unknown. We aim to evaluate in cases of pediatric astrocytomas, the frequency of polymorphisms in the TPT1 gene and other genes associated with its molecular pathways, such as MTOR, MDM2, TP53, and CDKN1A, correlating it with protein expression and clinical variables, in formalin-fixed, paraffin-embedded (FFPE) samples. These samples were submitted to genotyping and immunohistochemistry analyses. The most revealing results refer to the MDM2 gene, rs117039649 [G/C], in which C polymorphic allele was observed only in the glioblastomas ( p = .028). The CDKN1A gene, rs3176334 [T/C] presented a homozygous polymorphic genotype only in high-grade astrocytomas, when infiltrating tumors were compared ( p = .039). The immunohistochemical expression of cytoplasmic MDM2 correlated with better survival rates in patients with glioblastoma ( p = .018). The presence of polymorphisms in the MDM2 and CDKN1A genes, as well as a specific correlation between MDM2 expression, suggests a likely association with risk in pediatric astrocytomas. This study sought the probable role involved in the TCTP pathway, and associated proteins, in the tumorigenesis of pediatric astrocytomas, and some could have potential impact as prognostic markers in these patients.