Skip to main content

Research Repository

Advanced Search

The mammalian target of rapamycin complex 1 (mTORC1) in breast cancer: the impact of oestrogen receptor and HER2 pathways

Jerjees, Dena A.; Negm, Ola H.; Alabdullah, M. Layth; Mirza, Sameer; Alkaabi, Methaq; Hameed, Mohamed R.; Abduljabbar, Rezvan; Muftah, Abir; Nolan, Chris C.; Green, Andrew R.; Tighe, Patrick J.; Band, Vimla; Ellis, Ian O.; Rakha, Emad A.


Dena A. Jerjees

Assistant Professor

M. Layth Alabdullah

Sameer Mirza

Methaq Alkaabi

Mohamed R. Hameed

Rezvan Abduljabbar

Abir Muftah

Chris C. Nolan

Professor of Molecular Immunology

Vimla Band

Professor of Breast Cancer Pathology


The mammalian target of rapamycin complex 1 (mTORC1) is a downstream of the PI3K/Akt pathway which affects cancer development. mTORC1 has many downstream signalling effectors that can enhance different cellular responses. This study aims to investigate the expression of mTORC1 in breast cancer (BC) and correlate it with key clinicopathological and molecular features of BC especially to proteins related to oestrogen receptor (ER) and HER2 pathways in different BC classes. Moreover, mTORC1 expression was assessed in 6 BC cell lines including ER+ and ER? cell lines with and without HER2 transfection. Immunohistochemistry was used to assess the expression of phospho (p) mTORC1 in a large (n = 1300) annotated BC series prepared as tissue microarray. Reverse phase protein array (RPPA) was used to assess its expression in the different BC cell lines. The expression of p-mTORC1 was cytoplasmic with moderate/high expression noted in 44 % of BC. p-mTORC1 expression was associated with clinicopathological variables characteristic of good prognosis. Positive correlation with ER, ER-related proteins AKT, PI3K and luminal differentiation markers were observed in the whole series and in the ER+HER2? subgroup. Association with HER2 was mainly observed in the ER-negative class. RPPA indicated that p-mTORC1 expression was mainly related to ER expression and with better outcome in the Akt positive tumours. p-mTORC1 is associated with good prognostic features. Its expression is related to ER and ER related proteins in addition to AKT and PI3K. Its relation with HER2 expression is mainly seen in the absence of ER expression.


Jerjees, D. A., Negm, O. H., Alabdullah, M. L., Mirza, S., Alkaabi, M., Hameed, M. R., …Rakha, E. A. (2015). The mammalian target of rapamycin complex 1 (mTORC1) in breast cancer: the impact of oestrogen receptor and HER2 pathways. Breast Cancer Research and Treatment, 150(1), 91-103.

Journal Article Type Article
Acceptance Date Feb 9, 2015
Online Publication Date Feb 21, 2015
Publication Date 2015-02
Deposit Date Oct 17, 2018
Journal Breast Cancer Research and Treatment
Print ISSN 0167-6806
Electronic ISSN 1573-7217
Publisher Springer Verlag
Peer Reviewed Peer Reviewed
Volume 150
Issue 1
Pages 91-103
Public URL
Publisher URL