Open Access Research article

A comprehensive analysis of Aurora A; transcript levels are the most reliable in association with proliferation and prognosis in breast cancer

Satoko Yamamoto1, Mutsuko Yamamoto-Ibusuki1, Yutaka Yamamoto12*, Saori Fujiwara1 and Hirotaka Iwase1

Author Affiliations

1 Department of Breast and Endocrine Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo Kumamoto, Kumamoto 860-8556, Japan

2 Department of Molecular-Targeting Therapy for Breast Cancer, Innovation Center for Translational Research, Kumamoto University Hospital, 1-1-1 Honjo Kumamoto, Kumamoto 860-8556, Japan

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BMC Cancer 2013, 13:217  doi:10.1186/1471-2407-13-217

Published: 30 April 2013

Abstract

Background

Aurora A kinase, a centrosomal serine/threonine kinase which plays an essential role in chromosome segregation during cell division, is commonly amplified and/or over expressed in human malignancies. Aurora A is suggested to be one of the proliferation parameters which is an independent prognostic factor for early invasive breast cancer patients; however the individual clinical or prognostic relevance of this gene has been a matter of debate.

Methods

A comprehensive analysis of Aurora A at the levels of gene expression, gene copy number and protein expression was performed for 278 primary invasive breast cancer patients; and the correlation with clinical outcomes were investigated.

Results

Aurora A gene expression level not only correlated with gene amplification, but was also significantly associated with several clinicopathological parameters and patient prognosis. Patients with higher nuclear grade, negative progesterone receptor status and higher Ki67 expressed higher levels of Aurora A mRNA, which was associated not only with poor relapse-free survival (RFS) but was also found to be a significant multivariate parameter for RFS. Aurora A protein expression was also significantly associated with clinicopathological characteristics; lymph node status, nuclear grade, estrogen receptor status and Ki67, but not with prognosis. By contrast, Aurora A gene amplification correlated with tumor size, nuclear grade and Ki67, and had no prognostic value.

Conclusion

Our data indicate that Aurora A gene expression is an effective tool, which defines both tumor proliferation potency and patient prognosis.

Keywords:
Aurora A; Breast cancer; Biomarker; Transcript levels