Genetic Biomarker Test Could Guide Brain Cancer Treatment
Posted on 29 Jul 2025
Glioblastoma is the most aggressive form of brain cancer, accounting for about 15% of all brain tumors, and typically affects adults between the ages of 45 and 70. Despite treatment efforts, patients generally survive less than 15 months following diagnosis. Bevacizumab is commonly used to treat recurrent glioblastoma by blocking blood vessel growth in tumors and is associated with improvements in symptoms, quality of life, and progression-free survival. However, there has been no reliable way to predict which patients would benefit the most from this drug. This lack of predictive guidance exposes many patients to unnecessary side effects without assured therapeutic gain. Now, a newly discovered genetic biomarker could help identify glioblastoma patients who are most likely to benefit from bevacizumab.
Researchers at the University of Kentucky Markey Cancer Center (Lexington, KY, USA) conducted a large-scale study to uncover a biomarker that could help predict response to bevacizumab. The team analyzed tumor samples from 3,106 glioblastoma patients, including 571 who were treated with the drug. Using next-generation sequencing data, they compared the molecular profiles of patients who remained on treatment for varying durations. Their analysis revealed that brain tumors from patients who responded better and lived longer on bevacizumab were more likely to contain a genetic alteration known as CDK4 amplification.

The study, published in JCO Precision Oncology, represents the first large-scale research effort to identify molecular markers associated with prolonged response to bevacizumab in glioblastoma patients. The discovery of CDK4 amplification as a predictive biomarker has the potential to enable oncologists to make more informed treatment decisions by identifying those most likely to benefit from the drug. This advancement could minimize unnecessary treatment and associated toxicities for non-responders while ensuring timely access for those who may experience improved outcomes. Going forward, the research team aims to further validate the biomarker and explore its use in clinical decision-making frameworks for personalized brain cancer therapy.
“The findings could help oncologists make more informed treatment decisions for glioblastoma patients, potentially sparing those unlikely to benefit from unnecessary side effects while ensuring those who might respond get access to the drug,” said John Villano, M.D., Ph.D., Professor, UK College of Medicine, and lead author of the study
Related Links:
University of Kentucky Markey Cancer Center