[Progression and future of CDK4/6 inhibitors in hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer].

With the progress of tumor molecular biology research, the clinical treatment concept of advanced breast cancer gradually tends to be accurate. Hormone receptor (HR) positive and human epidermal growth factor receptor 2 (HER-2) negative breast cancer accounts for more than 70% of all breast cancers, and it is of great significance to explore new treatment strategies to break through the bottleneck of traditional treatment faced by the patient population. Targeted therapy for this type of breast cancer started relatively late. After the first cyclin-dependent kinase (CDK) 4/6 inhibitor Palbociclib entered the clinical application for HR positive and HER-2 negative advanced breast cancer patients in 2015, the clinical treatment pattern of HR positive and HER-2 negative advanced breast cancer has been changed significantly, with a consequent breakthrough improvement in patients' survival prognosis. Based on the basic pharmacological mechanism, the author analyzes the existing research data and puts forward opinions on how to achieve precise medication in clinical practice and wider application prospects in the future.