Peeing on a stick in the privacy of our bathrooms has long been a way to help us play doctor in our own homes. Diabetics can evaluate their glucose levels, would-be-moms can check on potential new pregnancies, and even pot users can judge the level of marijuana in their blood (or just get a good giggle watching a stick change color in a urine stream).
Soon, we might be able to use the pee-on-a-stick method for detecting cancer as well.
In research published this week in the Proceedings of the National Academy of Sciences, MIT Professor Sangeeta Bhatia reports that she and her team that developed paper test strips -- using the same technology behind in-home pregnancy tests -- that were able to detect colon tumors in mice.
The test strips work in conjunction with an injection of iron oxide nanoparticles, like those used as MRI contrast agents, that congregate at tumor sites in the body. Once there, enzymes known as matrix metalloproteinases (MMPs), which cancer cells use to invade healthy tissue, break up the nanoparticles, which then pass out through the patient's urine. Antibodies on the test strip grab them, causing gold nanoparticles to create a red color indicating the presence of the tumor.
Bhatia sees an immediate application for the technology in developing countries where complicated and expensive medical tests are a rarity. "For the developing world, we thought it would be exciting to adapt (the technology) to a paper test that could be performed on unprocessed samples in a rural setting, without the need for any specialized equipment," she said in a statement. "The simple readout could even be transmitted to a remote caregiver by a picture on a mobile phone."
Of the breakthrough, Samuel Sia, an associate professor of biological engineering at Columbia University not involved in the research said: "Extending this technology to detection by strip tests is a big leap forward in bringing its use to outpatient clinics and decentralized health settings."
To help Bhatia bring her idea to fruition, MIT has given her and her team a grant from the university's Deshpande Center for Technological Innovation. The purpose of the grant is to help the researchers develop a startup that could execute the necessary clinical trials and bring the technology to market.
Bhatia told Crave her team is next working on using the test to detect breast and prostate cancers, and that her goal is to one day be able to use it to find all types of cancer. "Eventually, we would hope that all solid tumors could be detected this way," she said. "They need to invade the surrounding tissue scaffolding using enzymes in order to spread and cause disease, so that's why we think we should be able to pick them up."