A research team at Baylor College of Medicine has made a new discovery in the field of ER+ breast cancer treatment, identifying a biomarker that may predict the efficacy of CDK4/6 inhibitors. The research results provide a new direction for personalized treatment, and the related paper has been published in the journal Science Translational Medicine.

The study focused on patients with estrogen receptor-positive (ER+) breast cancer, a type of cancer typically treated with endocrine therapy combined with CDK4/6 inhibitors. Through analysis of preclinical models and clinical trial data, the team found that in approximately 20% of patients, neurofibromin (NF1) levels in the tumor were significantly reduced. These patients showed a weaker response to endocrine therapy but a better therapeutic response to CDK4/6 inhibitors.

One of the study leaders, Dr. Eric Zhang, said: "When we add CDK4/6 inhibitors to fulvestrant, we can easily observe sustained tumor regression in PDX animal models." These findings were further supported by analysis of patient biopsy samples, showing that adding palbociclib to aromatase inhibitors improved treatment outcomes.

The team has now developed detection methods based on immunohistochemistry and mass spectrometry to measure NF1 protein abundance. Dr. Matthew Ellis pointed out: "We need more clinical studies to validate our findings. A major challenge is developing a reliable clinical assay to determine NF1 levels in patient samples."

This study provides a new path for advancing precision medicine in breast cancer and may help doctors more accurately identify patient groups suitable for CDK4/6 inhibitor therapy in the future.