Interplay between estrogen and retinoid signaling in breast cancer – Current and future perspectives

• Retinoic acid (RA) is a promising agent for breast cancer treatment.
• There is an interplay between retinoid and estrogen signaling in breast cancer cells.
• The combination of RA and antiestrogens synergistically decreases breast cancer cell proliferation.
• The combination of RA and antiestrogens is an appealing strategy for breast cancer therapy.

All-trans-retinoic acid (RA) is a promising agent for breast cancer treatment, but it induces several adverse effects and the few clinical trials performed up to now in breast cancer patients have provided disappointing results. The combination of RA and antiestrogenic compounds, such as tamoxifen, synergistically decreases the proliferation of breast cancer cells and an interplay between retinoid and estrogen signaling has begun to be unraveled, turning these combinations into an appealing strategy for breast cancer treatment. This review focus on the current knowledge regarding the interplay between retinoid and estrogen signaling in breast cancer and the combinations of RA with antiestrogens, aiming their future utilization in cancer therapy.