February 25, 2014
Improving Cancer Diagnosis Rates With New Paper Test Strip
Lee Rannals for redOrbit.com - Your Universe Online
Engineers at the Massachusetts Institute of Technology (MIT) have developed a paper test that could improve cancer diagnosis rates.
Cancer mortality rates can be drastically reduced with early detection, but some of these methods, such as mammography and colonoscopy, are unable to be used in developing nations. Cancer rates in these countries now account for 70 percent of mortality around the world, so a new method to detect the disease earlier is essential.
Researchers developed a paper test that works much like a pregnancy test, helping to reveal whether a person has cancer within minutes. This test could not only improve diagnoses rates, but also could help get people treated earlier.
The new technology uses nanoparticles that interact with tumor proteins known as proteases. These proteins can trigger the release of hundreds of biomarkers that are easily detectable in a person’s urine. The team simply took advantage of these biomarkers by using a highly specialized instrument to do the analysis.
"For the developing world, we thought it would be exciting to adapt it instead to a paper test that could be performed on unprocessed samples in a rural setting, without the need for any specialized equipment,” MIT professor and Howard Hughes Medical Institute investigator Sangeeta Bhatia, said in a statement. “The simple readout could even be transmitted to a remote caregiver by a picture on a mobile phone."
In order to develop the test strips, the team had to coat nitrocellulose paper with antibodies that are able to capture the peptides. Once these peptides are captured, they flow along the strip and are exposed to several invisible test lines made of other antibodies specific to different tags attached to the peptides. If one of these lines becomes visible, it means the target peptide is present in the sample.
Researchers were able to use the new technology to accurately identify colon tumors in mice. This test represents the first step towards a new type of diagnostic device that could one day be used in humans in developing nations.
"This is a new idea — to create an excreted biomarker instead of relying on what the body gives you," says Bhatia, senior author of a paper published in the Proceedings of the National Academy of Sciences. "To prove this approach is really going to be a useful diagnostic, the next step is to test it in patient populations."
She said the device will first be applied to high-risk populations, such as people who have had cancer previously, but eventually it would be used for early detection. Developed nations may also be able to use the device as a simple and inexpensive way to diagnose cancer.
"I think it would be great to bring it back to this setting, where point-of-care, image-free cancer detection, whether it's in your home or in a pharmacy clinic, could really be transformative," Bhatia said in a statement.