Newswise — Researchers at Michigan Technological University are shining new light on the hidden processes within cells, light that soon may provide an early tool for diagnosing and even treating cancer and other chronic diseases.
Inside our cells are processes that make or break us. They are tied to tiny organelles, such as mitochondria and lysosomes. To get a glimpse of those organelles, technologists infuse tissue samples with special dyes and observe them under powerful fluorescent microscopes.
When the dyes work, you can see a glowing image of the organelle. That image may someday be able to tell you if a cell is about to become cancerous or if the patient is coming down with Alzheimer's disease. Until now, however, those dyes had certain limitations. A team led by associate professor of chemistry Lanrong Bi has developed fluorescent dyes with powerful new properties: they work in acidic conditions, and they can trace hydroxyl radicals (also known as free radicals), very unstable molecules that are associated with a whole range of pathologies, including cancer and heart disease.
"It's difficult to monitor a cell's interior pH, because if a cell goes acidic, the commercial dye breaks down," said Bi. "But we have developed two dyes that become fluorescent under acidic conditions, which would make it much easier to monitor cells in a diseased state."
This property makes these dyes especially useful in imaging lysosomes, which serve as the cell's waste disposal system and have an interior pH of about 4.5. There's a good reason to look at lysosomes. "Their morphology changes as cells become cancerous," Bi said. "This could be used for very early diagnosis, when it's difficult to tell if a cell is cancerous or not."
Using a different type of fluorescent dye, her team has also been able to verify the presence of free radicals in mitochondria--organelles that generate most of the cell's energy--within colon cancer cells. "We do more than label mitochondria," said Bi. "We are focusing on detecting oxidative stress, which is characteristic of many pathologies, including Parkinson's, stroke and cancer."
The fluorescent dyes could be used for quick, safe, inexpensive diagnostic tests, Bi said. "Just put a cell sample on a slide, add the dye, and wait 30 minutes for it to go to the specific organelles," she said. Then look at it under a microscope.
She has filed a provisional patent on the new technology, which could also be used to help surgeons remove all malignant tissue from a tumor site.
Perhaps the best way to stop a tumor from spreading is to simply cut it all out. However, telling the difference between cancer cells and normal cells can be very difficult. Bi's fluorescent dyes could be used to establish the border between healthy and cancerous tissue. "We have developed a series of novel Superior-MitoProbes that lights up tumorous tissue like a neon sign and sets it off from non-cancerous tissue," she said.