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. )e 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: ?2 = 65,844; p < 0.0001; contingency coefficient: C = 0.1772; p < 0.0001). Evaluating the recurrent changes in at
least 50% of the samples, we observe as the most frequent losses of the segments 22q13.1-q13.2 (82%), 1p35.3 (76%), and 14q13.1-
q13.2 (67%), involving all histopathological grades. )e analysis of these regions showed the inclusion of genes with functions such
as regulation, maintenance of cell survival, reorganization of the cytoskeleton, cell signaling, and DNA repair, among others.
However, overall, the profiles observed in meningiomas of this admixed population were very similar to the ones observed in
Caucasian groups. An interesting finding was a recurrent gain of 8p22 observed only in grade I meningiomas, a region which
includes DLC1, a suppressor candidate gene probably implicated in the developments or progression of meningiomas, usually
found deleted, when related to CNAs.
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