Mechanisms of Tamoxifen Resistance: Increased Estrogen Receptor-HER2/neu Cross-Talk in ER/HER2-Positive Breast Cancer

Abstract

Tamoxifen behaves as an estrogen agonist in breast cancer cells that express high levels of AIB1 and HER2, resulting in de novo resistance. Gefitinib's ability to eliminate this cross-talk and to restore tamoxifen's antitumor effects should be tested in the clinic.