TORONTO--A new cancer-detecting device the size of a BlackBerry designed by a team of University of Toronto researchers may revolutionize the diagnosis and treatment of a wide range of cancers and other ailments.
Researchers say the microchip has enough sensitivity to detect early-stage cancer when it is most treatable.
According to scientists at the University of Toronto, the chip not only detects cancer but also can detect the type and severity of it. Built with nanowires, the chip is designed to sense trace amounts of cancer biomarkers, which are biologic molecules that indicate the presence or progression of a disease.
Because the signature biomarkers that indicate the presence of cancer at the cellular level are generally present only at low levels in biological samples, detecting them is a procedure that usually takes days and involves a room filled with computers. Now researchers have used nanomaterials to develop a microchip small enough to fit in a device the size of a mobile phone, and sensitive enough to do the job in 30 minutes.
The university hailed the technology as the latest move in the advent of nanomedicine.
"Today, it takes a room filled with computers to evaluate a clinically relevant sample of cancer biomarkers and the results aren't quickly available," says Shana Kelley, a lead investigator on the project and a professor in the Leslie Dan Faculty of Pharmacy and the Faculty of Medicine at the University of Toronto. "Our team was able to measure biomolecules on an electronic chip the size of your fingertip and analyze the sample within half an hour."
Kelley points out that diagnostic devices based on nanomaterials can be made much more sensitive than those based on conventional materials.
"This leap in sensitivity should promote more widespread use of molecular markers for diseases like cancer and promote the use of non-invasive tests, because the sensitivity will enable the analysis of the low levels of markers found in swabs, urine and blood samples," she says. "Having inexpensive, non-invasive tests for disease screening will enable physicians to detect disease early and more effectively treat it. In addition, realizing the promise of personalized medicine will also depend on having cheap and sensitive tests that will enable drugs to be prescribed with greater specificity. Nanomaterials may make all of this possible."
It is a technology that can offer scientists a number of advantages in the fight against cancer and myriad diseases.
"Treatment outcomes for many diseases, including cancer, are dependent on the stage at which a disease is detected," says Kelley. "Early detection makes many types of treatment more effective, and we believe that chip-based diagnostics like the one we developed will enable early diagnosis. In addition, we have engineered the platform to be inexpensive, which will enable its use in routine and cost-effective screening of patient samples for cancer markers and promote more effective diagnosis."
Although still in the engineering phase (doctors won't have the option of acquiring the devices for another two or three years) the device has been tested on prostate cancer and head and neck cancer models. It could potentially be used to diagnose and assess other cancers, as well as infectious diseases such as HIV, MRSA and H1N1 flu.
"Uniting DNA—the molecule of life—with speedy, miniaturized electronic chips is an example of cross-disciplinary convergence," said Ted Sargent, an engineering professor and another lead investigator in the project, in a statement. "By working with outstanding researchers in nanomaterials, pharmaceutical sciences, and electrical engineering, we were able to demonstrate that controlled integration of nanomaterials provides a major advantage in disease detection and analysis."
David Naylor, president of the University of Toronto and a professor of medicine, called "this remarkable innovation an indication that the age of nanomedicine is dawning."
Currently, Kelley's team is optimizing the microchip-based platform for different applications in oncological management, infectious disease diagnosis and pharmacogenetics, and is looking to commercialize the system in one of these areas.
"We have also built a prototype of a handheld chip reader that will assist with sample processing and analysis," she says.
As the work continues, Kelley says success is measured by documenting a high level of performance with clinical samples.
"So far, we have gotten good results with tissue samples, and are now moving on to samples collected non-invasively," she notes. "Our next milestones will include the detection of the low levels of biomarkers present in these types of samples."
Researchers increasingly have been using nanotechnology in their fight against cancer.
Scientists at the Washington University School of Medicine announced last month that they are creating "nanobees" to fight cancerous tumors. They are using nanoparticles to deliver bee venom called melittin through the body to kill cancerous tumor cells. In an experiment with mice, the nanobees targeted such tumors and effectively halted their growth, and in some cases even caused them to shrink.
Also in August, researchers at MIT announced that they had used nanoparticles to deliver genes to kill ovarian tumors in mice. The researchers said the tests could lead to a new treatment for ovarian cancer.
And in May, MIT scientists disclosed the development of gold nanoparticles that can heat cancerous tumors enough to kill them while leaving surrounding tissue undamaged. The researchers said tumors in mice that received the gold nanorod treatment disappeared within 15 days and that the cancer did not recur during the duration of the three-month study.
