After the publication of this work [1], an error was noticed in Fig. 2b and Fig. 4b as well as Fig.
View Article and Find Full Text PDFIntroduction: Upregulation of PI3K/Akt/mTOR signalling in endocrine-resistant breast cancer (BC) has identified mTOR as an attractive target alongside anti-hormones to control resistance. RAD001 (everolimus/Afinitor®), an allosteric mTOR inhibitor, is proving valuable in this setting; however, some patients are inherently refractory or relapse during treatment requiring alternative strategies. Here we evaluate the potential for novel dual mTORC1/2 mTOR kinase inhibitors, exemplified by AZD8055, by comparison with RAD001 in ER + endocrine resistant BC cells.
View Article and Find Full Text PDFIntroduction: Recently we reported that insulin receptor substrate 1 (IRS-1), classically an adaptor protein for the insulin-like growth factor type I receptor (IGF-IR), associates with the epidermal growth factor receptor in oestrogen receptor (ER)-positive (ER+) tamoxifen-resistant breast cancer cells. In this study, we examined whether IRS-1 also associates with another erbB receptor family member, erbB3, and what impact this might have on IGF-IR signalling in three ER+ breast cancer cell lines.
Methods: Immunoprecipitation and Western blot analysis were utilised to examine the potential association between erbB3 and IRS-1 in MCF-7, T47D and BT-474 cells in the absence and presence of the erbB3/4 ligand heregulin β1 (HRGβ1).
Introduction: We have previously reported that induction of epidermal growth factor receptor and ErbB2 in response to antihormonal agents may provide an early mechanism to allow breast cancer cells to evade the growth-inhibitory action of such therapies and ultimately drive resistant cell growth. More recently, the other two members of the ErbB receptor family, ErbB3 and ErbB4, have been implicated in antihormone resistance in breast cancer. In the present study, we have investigated whether induction of ErbB3 and/or ErbB4 may provide an alternative resistance mechanism to antihormonal action in a panel of four oestrogen receptor (ER)-positive breast cancer cell lines.
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