Meningiomas: An Overview of the Landscape of Copy Number Alterations in Samples from an Admixed Population
Michele Amaral da SilveiraWallax Augusto Silva FerreiraCarolina Koury Nassar AmorimJosé Reginaldo Nascimento BritoAndré Salim KayathFernanda do Espírito Santo SagicaEdivaldo Herculano Corrêa de Oliveira
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Meningiomas are considered the most common intracranial tumors, affecting mainly women. Studies in mixed populations can be of great importance to clarify issues related to the genetic diversity of tumors and their development. Considering that data obtained from analyses of the profile of copy number alterations (CNA) have been a useful diagnostic indicator for many types of tumors and that meningiomas show a complex pattern of gains and losses in the number of copies, our objective was to analyze the CNA profile in 33 samples of meningiomas of different histological grades (WHO Grade I-III) from patients in a city located in the Amazon region of Brazil, using aCGH. We found that the female to male ratio was 3 : 1. The aCGH analysis revealed a total of 2304 CNA, with an average of 69.8 ± 57.4 per case, of which 1197 were gains (52%), 926 were losses (40.2%), 105 were amplifications (4. 5%), and 76 were deletions (3.3%). A significant relationship was observed between the type of CNA and the degree of the tumor (chi-square test: χ 2 = 65,844; Keywords:
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