Cyclin-dependent kinase 4/6 inhibitors in breast cancer therapy

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• The retinoblastoma (Rb) tumor suppressor pathway is frequently dysregulated in breast cancer.
• Targeting the Rb pathway with cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors has emerged as a promising therapeutic strategy.

Purpose of the Study:

• To review current preclinical and clinical findings on CDK4/6 inhibitors in breast cancer.
• To update on studies investigating predictive biomarkers for response to CDK4/6 inhibitors.

Main Methods:

• Literature review of preclinical and clinical studies.
• Analysis of ongoing clinical trials investigating CDK4/6 inhibitors.
• Examination of research on biomarkers associated with CDK4/6 inhibitor response and resistance.

Main Results:

• CDK4/6 inhibitors show efficacy in hormone-receptor-positive and HER2-positive breast cancer, but their role in triple-negative breast cancer remains controversial.
• Alterations in the cyclin D-CDK4-Rb pathway are implicated in primary resistance to CDK4/6 inhibitors.
• Clinical trials are actively evaluating the safety and efficacy of various CDK4/6 inhibitors, primarily in hormone-receptor-positive breast cancer patients.

Conclusions:

• CDK4/6 inhibitors represent a significant advancement in breast cancer targeted therapy, particularly for hormone-receptor-positive subtypes.
• Identifying predictive biomarkers is crucial for selecting patients most likely to benefit from CDK4/6 inhibition.
• Biomarker-driven clinical trials are essential to optimize the use of CDK4/6 inhibitors in breast cancer management.