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Breast Cancer

, Volume 21, Issue 3, pp 382–385 | Cite as

Lack of genomic rearrangements involving the aromatase gene CYP19A1 in breast cancer

  • Maki FukamiEmail author
  • Junichi Suzuki
  • Kazuhiko Nakabayashi
  • Ryo Tsunashima
  • Tsutomu Ogata
  • Makio Shozu
  • Shinzaburo Noguchi
Rapid Communication

Abstract

Increased intratumoral expression of aromatase, the key enzyme for estrogen biosynthesis, is predicted to be of critical importance in the development of breast cancer. Recently, several germline rearrangements at 15q21 have been shown to cause overexpression of the aromatase gene CYP19A1 and resulting aromatase excess syndrome. To determine whether submicroscopic genomic rearrangements at 15q21 are involved in aromatase overexpression in breast cancer tissues, we investigated copy-number alterations in genomic DNA obtained from 44 tumor samples. Comparative genomic hybridization analysis identified no deletion or duplication at 15q21 in the 44 samples. These results, in conjunction with previous data, indicate that aromatase overexpression in breast cancer tissues is likely to result from a promoter switch of CYP19A1 and/or accumulation of CYP19A1-expressing cells, rather than from cryptic transactivation of CYP19A1 because of genomic rearrangements at 15q21.

Keywords

Breast cancer Aromatase CYP19A1 Gene expression Genomic rearrangement 

Abbreviations

AEXS

Aromatase excess syndrome

CGH

Comparative genomic hybridization

Notes

Acknowledgments

This work was supported by the Grant-in-Aid for Scientific Research on Innovative Areas (22132004) from the Ministry of Education, Culture, Sports, Science and Technology, by the Grant-in-Aid for Scientific Research (B) (23390249) from the Japan Society for the Promotion of Science, by the Grant for Research on Intractable Diseases from the Ministry of Health, Labor and Welfare, and by the Grants from National Center for Child Health and Development, from Takeda foundation, and from Daiichi-Sankyo Foundation of Life Science.

Conflict of interest

The authors declare that no conflict of interests exists.

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Copyright information

© The Japanese Breast Cancer Society 2013

Authors and Affiliations

  • Maki Fukami
    • 1
    Email author
  • Junichi Suzuki
    • 1
    • 2
  • Kazuhiko Nakabayashi
    • 3
  • Ryo Tsunashima
    • 4
  • Tsutomu Ogata
    • 1
    • 5
  • Makio Shozu
    • 6
  • Shinzaburo Noguchi
    • 4
  1. 1.Department of Molecular EndocrinologyNational Research Institute for Child Health and DevelopmentTokyoJapan
  2. 2.Department of Pediatrics and Child HealthNihon University School of MedicineTokyoJapan
  3. 3.Department of Maternal-Fetal BiologyNational Research Institute for Child Health and DevelopmentTokyoJapan
  4. 4.Department of Breast and Endocrine SurgeryOsaka University Graduate School of MedicineOsakaJapan
  5. 5.Department of PediatricsHamamatsu University School of MedicineHamamatsuJapan
  6. 6.Department of Reproductive Medicine, Graduate School of MedicineChiba UniversityChibaJapan

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