What is a Biomarker, and how can it help diagnose cancer?
A major complication in the treatment of cancer is late detection. Better methods to diagnose cancer at the early stages means a large improvement in the successful outcomes after treatment. But how do you find cancer early before it is causing symptoms? When the tumor is still too small to be easily detected through current methods? One option is to use biomarkers. Biomarkers are a variety of small molecules including proteins and certain types of RNA that cancer cells shed into the body that are different from the molecules healthy cells shed. If clinicians could identify these then a simple blood, saliva or urine screen could be done to regularly look for cancer.
Unfortunately, biomarkers are difficult to work with. They are typically easily broken down by the body and are also only found at extremely low concentrations making them difficult to detect when they are present. Luckily there are many researchers out there who are working to overcome these limitations in order to make these types of tests a viable option for screening for cancer. One such researcher is Sangheeta Bhatia at MIT.
Dr. Bhatia has been working on a novel solution to this problem in her lab by developing synthetic biomarkers. These molecules, when administered to the patient, circulate until they come in contact with cancerous cells which they are able to specifically recognize. Once the synthetic biomarkers are in the tumor, abnormally active enzymes inside of the tumor cut the biomarker in two. This allows a portion of the original molecule to show up in the urine of the patient to be detected by the clinician. Her method does not only tell the research whether disease is present but is actually able to distinguish between two different diseases depending on how the biomarker is cut. This is possible because the enzymes which cut her biomarker are different in different diseases. For example, Dr. Bhatia has shown that her synthetic biomarkers are able to distinguish between liver fibrosis and cancer in an animal model.
These types exciting advances in the detection of cancer will lead to much earlier detection of cancer while tumors are smaller and easier to treat. I look forward to watching Dr. Bhatia’s research as it moves closer to clinical trials and, hopefully, one day soon, into regular use in doctor’s offices.
Reviewed by Stephanie Byng.
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