Zahra Farhoud - Department of veterinary medicine Rasht Branch, Islamic Azad university,
Sepehr Bozorgchenani - Department of Bioinformatics, Tehran branch, Science and Culture University,

Despite advances in early detection, treatment regimens, and an understanding of the molecular basis of breast cancer biology, approximately ۳۰% of early-stage breast cancer patients have a recurrent disease that is mostly metastatic. Tumor is hormone-dependent and estrogen plays a major role in the spread and progression of the disease. Targeting ER has been a reliable treatment for all stages of breast cancer. In this study, we looked at the challenges, therapeutic implications, prognosis and resistance of breast tumors. We discuss selective estrogen receptor modulators such as tamoxifen and the role of nanoparticles in minimizing these problems. Despite the obvious benefits of tamoxifen in the treatment and / or chemical prevention of breast cancer, most breast tumors that are initially responsive experience a recurrence, indicating that patients eventually developed antiestrogen resistance. The effectiveness of this drug requires studies. It is important to understand the mechanism of action of different cells against nanomaterials to provide a more accurate assessment of the dangers of nanomaterials. Once this knowledge gap is closed, researchers can design improved formulation strategies to protect healthy cells from possible nanomaterial-related poisonings

estrogen receptor, breast cancer, tamoxifen, nanoparticles