New research could bring us closer to automated cancer detection
Saint Mary’s University’s laser-scanning microscope could have positive diagnostic implications for the future
Cancer affects us all - it seems as if everyone has been impacted either directly or indirectly by it. Dr. Danielle Tokarz at Saint Mary’s University (SMU) is involved with groundbreaking research that will hopefully have a significant impact on early cancer detection.
Dr. Tokarz and her team at SMU build custom laser-scanning microscopes to investigate diseased tissue. These unique and highly specialized microscopes, called Second Harmonic Generation (SHG) microscopes, use a laser that introduces a large amount of light energy into very small regions of tissue sample, for a very short amount of time.
“What this does is create a bombardment of energy, and certain biological structures naturally produce what we call ‘optical harmonic signals’,” says Dr. Tokarz, who is an associate professor of chemistry at SMU. “We can collect these signals and then we use them to image and structurally analyze the biological tissue.”
Traditionally, diagnosis for diseased tissue is performed by obtaining a thin tissue section from a biopsy, which would be dyed with a stain. A pathologist would then look at the tissue under a white-light microscope, and observe any irregularities in the tissue. However, with the technique that Dr. Tokarz and her team employ, there is no need for staining, and the determination can be made automatically by a machine, resulting in early diagnosis.
“So instead, what happens is the collagen, which is a protein naturally present in tissue, actually produces these optical harmonic signals by itself, as long as we are focusing our laser on it,” she says. “Then, using our technique, we’re able to pull out some information about the structure of collagen. It’s been found that with cancer in particular, as well as some other diseases, the collagen in tissue becomes disorganized, which we are able to sensitively detect.”
Collagen is the most abundant protein in humans, and the collagen found in organ tissues generates strong SHG signals without staining. This has diagnostic implications for the future. The hope is one day, they will be able to make this technique fully automated, highlighting the regions of concern (potentially diseased or cancerous tissues), for the pathologist to review. This would guide treatment plans, as well as helping to avoid human error.
“Tissue morphologically is so different from patient to patient, so it can be very difficult to tell sometimes if it’s cancerous or diseased,” says Dr. Tokarz. “That is why an automated technique would be so beneficial.”
Dr. Tokarz’s laboratory has studied lung cancer, breast cancer, pancreatic cancer, as well as thyroid cancers and diseases. They are currently working on trying to detect kidney and stomach cancer. This technique is quite unique, with only approximately five to ten groups worldwide using a similar approach to detect cancer. While they are still in the initial phases, there are huge implications for what this could mean diagnostically, moving forward.
This significant research that
Dr. Tokarz and her team at SMU conduct has a direct application to helping humankind. Her team is interdisciplinary, with physicists, chemists, biologists, and engineers joining her research group to work on this topic. They are also working with collaborators at the University of Toronto and the Toronto University Health Network.
Dr. Tokarz’s team includes undergraduate students that are doing the research as well, which is an incredible learning opportunity for students at that level.
“Interdisciplinary science is the way forward,” says Dr. Tokarz. “This topic is really multifaceted, and involving researchers in different fields is needed to solve this astronomical human health problem.”
For more information on the great research taking place at Saint Mary’s University, visit https://www.smu.ca/ research/welcome.html