Tamoxifen resistance mechanisms in breast cancer treatment

Therapies targeting estrogen receptor (ER) are being widely used to treat ER+ breast cancer patients. Despite early detection and improved survival outcomes, tamoxifen resistance, either intrinsic or acquired- is a major obstacle in effective disease management. Current review will summarize different molecular mechanisms of tamoxifen resistance both intrinsic and acquired in breast cancer treatment. This review not only provides basis to understand the nature of tamoxifen drug resistance but also suggests the mechanisms for its control leading to improved therapeutic interventions.