New Genomic Test Aims to Predict Chemotherapy Resistance

Researchers at the Spanish National Cancer Research Centre (CNIO), in collaboration with the University of Cambridge, have developed a genomic test designed to predict which cancer patients will not respond to common chemotherapy drugs. This method, detailed in Nature Genetics, focuses on identifying biomarkers linked to chromosomal instability patterns in tumors, enabling a more precise use of chemotherapy.

Chemotherapy has been a standard cancer treatment for decades, aiming to destroy tumor cells. However, it is not effective for all patients—between 20% and 50% do not respond to these drugs and endure side effects without clinical benefit. Geoff Macintyre, senior author of the paper, states, “We’ve found a way to practice precision medicine with standard chemotherapy.” The test quantifies biomarkers for platinum-, taxane-, and anthracycline-based chemotherapies, which are widely used but were not originally developed as targeted therapies.

The approach relies on detecting characteristic signatures of chromosomal instability, which arise because many tumors have abnormal numbers of chromosomes in their cells. Co-first author Laura Madrid explains that these changes mean “cancer cells do not have the correct amount of genetic material.” By identifying these signatures, the test can predict resistance to chemotherapy, allowing patients to avoid unnecessary side effects.

The team validated their biomarkers using data from 840 patients with breast, prostate, ovarian, and sarcoma cancers, demonstrating the test’s efficacy across multiple cancer types. Following this success, further development is underway to extend the technology to other targeted therapies.

Clinical validation is underway and expected to be completed by 2026. “Taking a biomarker from the discovery phase to the clinic is rarely easy. But with persistence and collaboration, it's possible to turn a research project into a truly promising technology,” says Macintyre.