New CRISPR Blood Test Detects Lung Cancer Biomarkers
Researchers have developed a new CRISPR-powered optical blood test capable of detecting lung cancer biomarkers at near-zero concentrations. The test offers a more sensitive method for early detection than current techniques like PCR or imaging, potentially identifying the disease at its earliest stages.
- This new diagnostic approach combines DNA nanotechnology, quantum dots, and CRISPR-Cas12a gene-editing tools to detect microRNA biomarkers for lung cancer. The technology was developed by a team led by Han Zhang at Shenzhen University in China. - A key innovation is the use of a light-based signal called second harmonic generation (SHG), which creates very little background noise. When the CRISPR tool finds a cancer biomarker, it cuts DNA holding quantum dots in place, causing a measurable drop in the light signal. - The current gold standard for screening high-risk individuals is the low-dose CT (LDCT) scan; however, this method has limitations, including a high rate of false positives, radiation exposure, and low compliance. Less than 5% of people with nodules found through CT scans actually have lung cancer. - This new test can detect biomarkers at sub-attomolar levels, meaning only a few molecules need to be present in a blood sample for detection. This is more sensitive than conventional methods like RT-qPCR, which require amplifying genetic material to measurable levels. - In a study using blood samples from 10 lung cancer patients and 5 healthy individuals, the new sensor showed stronger signal discrimination between the two groups than RT-qPCR. It could also distinguish the target biomarker from other closely related microRNA sequences. - The technology is programmable and could potentially be adapted to detect other diseases by targeting different biomarkers, including those for viruses or Alzheimer's disease. - This type of "liquid biopsy" can also be used to monitor how well a treatment is working by tracking changes in the levels of circulating tumor DNA (ctDNA). This offers a non-invasive way to assess treatment efficacy on a daily or weekly basis, much faster than waiting months for imaging results.
