Prognostic significance of androgen receptor expression in invasive breast cancer: transcriptomic and protein expression analysis

Aleskandarany, Mohammad A.; Abduljabbar, Rezvan; Ashankyty, Ibraheem; Elmouna, Ahmed; Jerjees, Dena; Ali, Simak; Buluwela, Laki; Diez-Rodriguez, Maria; Caldas, Carlos; Green, Andrew R.; Ellis, Ian O.; Rakha, Emad A.

Abstract

Differential prognostic roles of Androgen Receptor (AR) have been proposed in breast cancer (BC) depending on tumour oestrogen receptor (ER) status. This study aimed to evaluate the prognostic and/or predictive significance of AR expression in invasive BC. In this study AR expression was studied on a large (n = 1141) consecutive series of early-stage (I–III) BC using tissue microarray and immunohistochemistry (IHC). AR mRNA expression was assessed in a subset of cases. The prognostic impact of AR mRNA expression was externally validated using the online BC gene expression data sets (n = 25 data sets, 4078 patients). Nuclear AR IHC expression was significantly associated with features of good prognosis including older age, smaller tumour size, lower grade and lobular histology particularly in the ER-positive tumours. AR was associated with ER-related markers GATA3, FOXa1, RERG and BEX1. Negative association was observed with HER2, p53, Ki67, TK1, CD71 and AGTR1. AR Overexpression was associated with longer survival (p less than 0.001), independent of tumour size, grade, stage [p = 0.033, hazard ratio (HR) = 0.80 95 % CI = 0.64–0.98]. Similar associations were maintained in ER+ tumours in univariate and multivariate analysis (p less than 0.01) both in patients with and without adjuvant endocrine or chemotherapy. AR mRNA expression showed significant association with tumour grade, molecular subtypes, and longer 10 and 15 years survival in luminal BC. In the external validation cohorts, AR gene expression data were associated with improved patients’ outcome (p less than 0.001, HR = 0.84, 95 % CI 0.79–0.90). AR is not only an independent prognostic factor in ER-positive luminal BC but is also expressed in ER-negative tumours. AR could act as a molecular target in patients with ER-positive disease predicting response to adjuvant therapy.

Citation

Aleskandarany, M. A., Abduljabbar, R., Ashankyty, I., Elmouna, A., Jerjees, D., Ali, S., Buluwela, L., Diez-Rodriguez, M., Caldas, C., Green, A. R., Ellis, I. O., & Rakha, E. A. (2016). Prognostic significance of androgen receptor expression in invasive breast cancer: transcriptomic and protein expression analysis. Breast Cancer Research and Treatment, 159(2), 215-227. https://doi.org/10.1007/s10549-016-3934-5

• Journal Article Type: Article
• Acceptance Date: Aug 1, 2016
• Online Publication Date: Aug 11, 2016
• Publication Date: Sep 30, 2016
• Deposit Date: Oct 15, 2018
• Journal: Breast Cancer Research and Treatment
• Print ISSN: 0167-6806
• Electronic ISSN: 1573-7217
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 159
• Issue: 2
• Pages: 215-227
• DOI: https://doi.org/10.1007/s10549-016-3934-5
• Public URL: https://nottingham-repository.worktribe.com/output/1166839
• Publisher URL: https://link.springer.com/article/10.1007%2Fs10549-016-3934-5