Dataset Information

Gene copy number variation in male breast cancer by aCGH.

ABSTRACT:

Background

Male breast cancer (MBC) is a rare disease and little is known about its etiopathogenesis. Array comparative genomic hybridization (aCGH) provides a method to quantitatively measure the changes of DNA copy number and to map them directly onto the complete linear genome sequences. The aim of this study was to investigate DNA imbalances by aCGH and compare them with a female breast cancer dataset.

Methods

We used Agilent Human Genome CGH Microarray Kit 44B and 44K to compare genomic alterations in 25 male breast cancer tissues studied at NCC of Bari and 16 female breast cancer deposited with the Gene Expression Omnibus (GSE12659). Data analysis was performed with Nexus Copy Number 5.0 software.

Results

All the 25 male and 16 female breast cancer samples displayed some chromosomal instability (110.93 alterations per patient in female, 69 in male). However, male samples presented a lower frequency of genetic alterations both in terms of loss and gains.

Conclusion

aCGH is an effective tool for analysis of cytogenetic aberrations in MBC, which involves different biological processes than female. Male most significant altered regions contained genes involved in cell communication, cell division and immunological response, while female cell-cell junction maintenance, regulation of transcription and neuron development.

SUBMITTER: Tommasi S

PROVIDER: S-EPMC4605520 | biostudies-literature | 2010

REPOSITORIES: biostudies-literature

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Publications

Gene copy number variation in male breast cancer by aCGH.

Tommasi Stefania S Mangia Anita A Iannelli Giuseppina G Chiarappa Patrizia P Rossi Elena E Ottini Laura L Mottolese Marcella M Zoli Wainer W Zuffardi Orsetta O Paradiso Angelo A

Analytical cellular pathology (Amsterdam) 20100101 3

<h4>Background</h4>Male breast cancer (MBC) is a rare disease and little is known about its etiopathogenesis. Array comparative genomic hybridization (aCGH) provides a method to quantitatively measure the changes of DNA copy number and to map them directly onto the complete linear genome sequences. The aim of this study was to investigate DNA imbalances by aCGH and compare them with a female breast cancer dataset.<h4>Methods</h4>We used Agilent Human Genome CGH Microarray Kit 44B and 44K to comp ...[more]

PMID: 21045282

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Project description:BackgroundOverall, HER2-amplified female breast cancer (FBC) is associated with a high grade, an aggressive phenotype and a poor prognosis. In male breast cancer (MBC) amplification of HER2, located on chromosome 17, occurs at a lower frequency than in FBC, where it is part of complex rearrangements. So far, only few studies have addressed the occurrence of chromosome 17 alterations in small MBC cohorts.MethodsMultiplex ligation-dependent probe amplification (MLPA) and fluorescence in situ hybridization (FISH) were used to detect and characterize copy number changes on chromosome 17 in a cohort of 139 MBC. The results obtained were compared to those in FBC, and were correlated with clinicopathological features and patient outcome data.ResultsWe observed a lower frequency of chromosome 17 copy number changes with less complex rearrangement patterns in MBC compared to FBC. Chromosome 17 changes in MBC included gains of 17q and losses of 17p. Whole chromosome 17 polyploidies were not encountered. Two recurrent chromosome 17 amplicons were detected: on 17q12 (encompassing the NEUROD2, HER2, GRB7 and IKZF3 gens) and on 17q23.1 (encompassing the MIR21 and RPS6KB1 genes). Whole arm copy number gains of 17q were associated with decreased 5 year survival rates (p = 0.010). Amplification of HER2 was associated with a high tumor grade, but did not predict patient survival. Although copy number gains of HER2 and NEUROD2 were associated with a high tumor grade, a high mitotic count and a decreased 5 year survival rate (p = 0.015), only tumor size and NEUROD2 copy number gains emerged as independent prognostic factors.ConclusionsIn MBC chromosome 17 shows less complex rearrangements and fewer copy number changes compared to FBC. Frequent gains of 17q, encompassing two distinct amplicons, and losses of 17p were observed, but no whole chromosome 17 polyploidies. Only NEUROD2 gains seem to have an independent prognostic impact. These results suggest different roles of chromosome 17 aberrations in male versus female breast carcinogenesis.

Dataset Information

Gene copy number variation in male breast cancer by aCGH.

Background

Methods

Results

Conclusion

Publications

Gene copy number variation in male breast cancer by aCGH.

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