帮我润色这段学术论文Breast cancer is the most prevalent cancer among women worldwide and its death rate remains high 1 Most of the molecular subtypes are classified according to the expression of estrogen recep

Breast cancer is a prevalent cancer worldwide, and despite advancements in treatment, its death rate remains high [1]. Molecular subtypes of breast cancer are often classified based on the expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2), and are typically categorized into four types: LminalA (ER+ or PR+, HER2-), LminalB (ER+ or PR+, HER2+), triple-negative breast cancer and Her2+ breast cancer [2]. Among these subtypes, ER+ breast cancer is the most common, accounting for nearly 80% of cases[3].

The activation of ER by estrogen is a significant contributor to the development of ER+ breast cancer. This activation leads to the transcription of pro-survival genes via genomic regulation and the promotion of cellular signaling via non-genomic regulation, ultimately leading to the proliferation of cancerous breast tissue. Moreover, ER targets are present in other organs, such as the uterus, bones, and brain, and have been linked to other diseases, including osteoporosis, endometrial cancer, and neurodegenerative diseases.

Endocrine therapy, including selective estrogen receptor degraders (SERD), is an effective treatment for ER+ breast cancer and other ER-related diseases. Fulvestrant, the only FDA-approved drug currently on the market, is commonly used as an endocrine therapy in breast cancer treatment after aromatase inhibitor failure. Additionally, SERD can be co-administered with other drugs, such as GDC-9545 (a novel oral SERD) and CDK4/6 inhibitors. Research on SERD has been intense in recent years, with nearly a dozen SERDs entering clinical trials. For instance, the combination of Palbociclib with GDC-9545 resulted in up to 24% degradation in a mouse tumor model, and in a tumor model resistant to GDC-9545, the combination with Palbociclib increased degradation potency. AZD9833, a SERD, has entered clinical phase III (NCT 04964934)