Prostate cancer is the most common cancer for men in Canada, affecting one in seven, and killing about 16 per cent of those diagnosed. Caught early and the survival rate is high – but beyond invasive biopsies, methods for early detection are controversial and prone to false-positives.
Researchers at the University of Victoria are developing distinctly separate high-tech techniques that could lead to relatively easy early detection and non-invasive treatment of prostate cancer. One method uses nanoparticles and the other acoustic beams, but both hold promise to save lives down the road.
Nanoparticles, a cargo against cancer
Frank van Veggel places a small vial of clear liquid in the path of a laser and it glows neon green, proof of the microscopic nanoparticles inside.
Nanoparticles, objects on the scale of a billionth of a metre, could be the ticket to better imaging of tumours and possibly as a delivery system to kill the cancer itself. The chemistry professor is developing the technology at his UVic lab in partnership with the Victoria branch of the B.C. Cancer Agency.
Currently, the prostate specific antigen (PSA) test and digital rectal exams are the most common ways to detect prostate cancer. PSA tests look for changes in PSA levels over time – a rapid increase could indicate cancer, or it could be something unrelated. Digital rectal exams seek changes and irregularities in the prostate, which may or may not mean the disease is present. A biopsy typically is needed to confirm cancer.
“It’s complicated to have specific tests for prostate cancer. That tells us it is a huge challenge,” Van Veggel says.
Van Veggel started talking with the BCCA about using nanoparticles about a decade ago, and since then has received eight patents and has two more under review related to developing nano-technology for imaging.
He’s figured out ways to attach nanoparticles, all made of rare earth elements, to an antibody that will seek out diseased prostate tissue. Those nanoparticles in turn will emit light in an MRI imaging machine, or could even be engineered to carry bits of radioactive material directly into the tumour, offering highly focused radiation therapy that could reduce its toxic side effects.
“With high magnetic fields (like in an MRI), there are no good contrast agents. That’s where nanoparticles have a clear advantage,” Van Veggel says. “I see the antibody is a vehicle and the nanoparticle is the cargo. The antibody delivers the nanoparticle which is used in imaging, and hopefully in the future, (radiation) therapy as well.”
Wayne Beckham, head of medical physics for the B.C. Cancer Agency-Vancouver Island, works with the agency’s Centre for Innovative Radiation Therapy and Informatics, which seeks novel ways to improve outcomes for cancer patients.
“As a group we are always looking for new technologies and new ideas to help with the diagnosis and treatment of cancer patients. It’s why Frank’s nanoparticle work is interesting to us,” Beckham says. “He is able to manufacture nanoparticles designed to carry various cargo. Nanoparticles can help boost the imaging signals and help detect cancer in a more effective way.”
Beckham noted that testing nanotechnology directly in humans is still years down the road. Van Veggel still needs to definitively show that nanoparticles will flush from the body, aren’t toxic and are better than existing imaging agents. Van Veggel said nanotechnology in humans is like drug development – it can take 15 years before it hits the market.
“Frank’s got to finish his work on how nanoparticles respond in cell systems … before its used in humans,” Beckham says.
“We think this has a lot of potential. It’s why we are interested in working with Frank. It’s interesting enough to put in the time and effort to move this to the next phase.”
The sound of a tumour
UVic mechanical engineering professor Rodney Herring has spent the last 10 years designing and building the most powerful electron microscope on Earth, a device that was opened to researchers just this month.
As a project off the side of his desk for eight years, Herring has also developed a device to detect and diagnose prostate cancer using sound waves, similar to beams used in an ultrasound.
His device focuses high frequency sound onto a prostate – a lumpy green artificial version so far – and the reflected, scattered signals are measured and used to build an image of prostate tissue. Herring uses the same physical principles to interrogate materials with electron beams in the one-of-a-kind scanning transmission electron holography microscope (STEHM) at UVic.
“(The medical imaging tool) can see diseased tissue in the prostate, but it’s not invasive. It not only sees the diseased tissue, it can diagnose the state of the diseased tissue,” Herring said. “I believe the same device can treat the diseased tissue and monitor the process. It’s like four machines in one.”
Engineer Peter Jacquemin has tested and refined the device, and its software and hardware. The proof of concept is complete, Herring said, and the project needs funding to advance out of the lab. Herring needs several hundred thousand dollars to test the technology on actual cancerous prostate tissue and to shrink the cumbersome prototype to the size of a wand.
Herring said getting consistent funding for this project has been difficult. If the device can find funding backers and reach a stage of human testing, it could replace the PSA blood test with a medical tool that provides quick, clear diagnoses, Herring said.
“Studies show PSA levels have no bearing on cancer in the prostate,” he said. “The only way is to go in and remove tissue. It is a major disease of men. It’s why we need a better method and why we are focusing on the prostate.
“I don’t need to do this project, but I’ve made it personal and given it a high priority,” he says. “I think this solves the prostate problem. There isn’t another method where you can see the disease and diagnose the diseased region. This has a high potential to save lives.”
UVic mechanical engineering professor Rodney Herring and engineering PhD Peter Jacquemin are developing a medical imaging tool that uses focused sound beams to detect and diagnose prostate cancer. The green model prostate sits in the centre of the prototype device, part of which is covered in plastic to obscure proprietary engineering.