Stanford Researchers Develop Breakthrough Liquid Biopsy for Cancer Resistance and Tissue Injury
Researchers at Stanford Medicine have developed a new blood test that can detect cancers, identify treatment resistance, and monitor tissue damage caused by non-cancerous conditions. The test works by analysing fragments of RNA found circulating in the bloodstream, known as cell-free RNA (cfRNA).
These RNA fragments are released during the natural process of cell death, coming from various tissues and organs, including cancerous tumours. Although cfRNA is less abundant in blood than DNA, it provides valuable information about gene activity across the body.
Over six years, the Stanford team created a method to specifically detect messenger RNA (mRNA), a type of cfRNA that signals which genes are being expressed as proteins. By focusing on around 5,000 genes that are rarely found in healthy blood samples, the researchers were able to significantly improve the test’s accuracy. In cases of lung cancer, for instance, the test detected cancer RNA in 73% of patients, including those in early stages.
Unlike many DNA-based tests that rely on genetic mutations, this cfRNA-based approach can detect biological changes linked to treatment resistance that are not caused by genetic alterations. This makes it a valuable tool for early detection of when a cancer therapy may be losing effectiveness, potentially allowing clinicians to adjust treatments before symptoms worsen or disease progression becomes visible through scans.
To improve the test’s accuracy, the team addressed the influence of platelets, which carry RNA but not DNA, and can interfere with results. By using a combination of molecular techniques and computational tools, they filtered out the unwanted platelet RNA signals. This refinement ensures the test works not only on fresh blood samples, but also on archived samples from previous clinical studies.
This opens the possibility of using existing biobanked samples to identify biomarkers and predict treatment outcomes, offering a quicker path to developing personalised therapies.
