Genetic alterations detected by comparative genomic hybridization in BRCAX breast and ovarian cancers of Brazilian population

// Paula Silva Felicio 1 , Lucas Tadeu Bidinotto 1, 2 , Matias Eliseo Melendez 1 , Rebeca Silveira Grasel 1 , Natalia Campacci 1 , Henrique C.R. Galvao 3 , Cristovam Scapulatempo-Neto 4 , Rozany Mucha Dufloth 4 , Adriane Feijo Evangelista 1 and Edenir Inez Palmero 1, 2 1 Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, SP, Brazil 2 Barretos School of Health Sciences-FACISB, Barretos, SP, Brazil 3 Department of Oncogenetics, Barretos Cancer Hospital, Barretos, SP, Brazil 4 Department of Pathology, Barretos Cancer Hospital, Barretos, SP, Brazil Correspondence to: Edenir Inez Palmero, email: edenirip@yahoo.com.br Keywords: BRCAX; hereditary breast cancer; hereditary breast and ovarian cancer predisposition syndrome; CNV alterations Received: August 09, 2017      Accepted: May 14, 2018      Published: June 08, 2018 ABSTRACT Background: About 5–10% of breast/ovarian cancers are hereditary. However, for a large proportion of cases (around 50%), the genetic cause remains unknown. These cases are grouped in a separated BRCAX category. The aim of this study was to identify genomic alterations in BRCA1/BRCA2 wild-type tumor samples from women with family history strongly suggestive of hereditary breast/ovarian cancer. Results: A cohort of 31 Brazilian women was included in the study. Using the GISTIC algorithm, we identified 20 regions with genomic gains and 31 with losses. The most frequent altered regions were 1q21.2, 6p22.1 and 8p23.3 in breast tumors and Xq26 and Xp22.32-22.31 among the ovarian cancer cases. An interesting association identified was the loss of 22q13.31-13.32 and the presence of ovarian cancer cases. Among the genes present in the frequently altered regions, we found FGFR1 , NSMCE2 , CTTN , CRLF2 , ERBB2 , STARD3 , MIR3201 and several genes of RAET and ULBP family. Conclusions: In conclusion, our results suggest that alterations on chromosomes 1, 6, 8 and X are common on BRCAX tumors and that the loss on 22q can be associated with the presence of ovarian cancer. Methods: DNA copy number alterations were analyzed by 60K array comparative genomic hybridization in breast and ovarian FFPE tumors.