AKT signalling implicated in failure of endocrine therapy

Excerpt

Acquisition of endocrine resistance is a persistent problem in oestrogen receptor (ER) positive breast cancer. This phenomenon is likely to be underpinned by signalling mechanisms that enhance cell survival and proliferation. PI3 kinase/AKT signalling, which lies downstream of tyrosine kinase receptors including c-erbB2, can phosphorylate ER in a hormone independent manner and protect breast cancer cells from tamoxifen-induced apoptosis in vitro (see Additional information [1]). However, the contribution of this pathway to endocrine resistance in vivo is currently unknown. This immunocytochemical study begins to address the impact of AKT protein and its phosphorylation (pAKT) in 93 breast cancer patients treated with endocrine therapy, monitoring these parameters versus tumour clinicopathology and disease-free survival. …