A quicker diagnosis for early stages of colorectal cancer would save lives. Combining biology with electronics, Sefi Vernick, a PhD student at Tel Aviv University, hopes to provide just that. By adding lab-on-a-chip technology to an endoscope, his work should enable doctors to test for cancer biomarkers during internal examinations.
Vernick is working on biosensors, mainly electrochemical, for cancer detection as part of a group effort to develop biomedical devices. As the third-most common cancer, early diagnosis is important. "It's also widely accepted that, since cancer is the sum of many cellular events manifesting in many ways, the solution lies in multi-target strategies. A simultaneous detection of biomarkers may increase level of confidence [for detection] considerably," says Vernick.
Biomarkers are commonly used in medical diagnostics to indicate a disease state. Cancer biomarkers are molecular changes detectable in the tumour as well as blood, urine or other body fluids with these telltale signs being produced in the tumour or by the body itself. But there's a problem: "CRC [colorectal cancer] is a greater challenge since its biomarkers aren't sufficiently specific."
Endoscopes allow doctors to examine the rectum and colon, take biopsy samples, and remove small polyps that may develop into cancers. By fitting lab-on-a-chip technology to an endoscope, cancer biomarkers are detectable too. "This tool allows us to both visualise and remove polyps and screen for cancer in real time.".
At the moment, he relies on the presence of a single biomarker for healthy cells not found in cancer cells. The lab-on-a-chip acts as an electrochemical biosensor for this biomarker (which catalyses the substrate) with electrodes transducing a signal into a measurable electric current. Filters help reduce biological noise within this "highly sensitive" method. The research, which is partly funded by American-Israeli businessman and philanthropist Lester Crown, also hopes to add further cancer biomarkers to increase the level of confidence in the results.
The new research is welcomed by Dr Alison Ross, senior science information officer at Cancer Research UK. "There are many questions that need answering before we know whether this potential new test is accurate and reliable and provides benefits over existing methods," she says.
"This new technology is just one example of the huge research effort to identify biomarkers that can aid cancer diagnosis. But any new way of speeding up the diagnosis of bowel cancer would be very welcome."
Ross also points out that when cancer is detected early, treatment is often simpler and more likely to be effective. The UK has already introduced a bowel cancer screening programme using the faecal occult blood test to check for early signs.
