Researchers have witnessed for the first time cancer cells targeted and destroyed from the inside, by an organo-metal compound discovered by the University of Warwick.
Professor Peter J. Sadler and his group in the Department of Chemistry demonstrated that Organo-Osmium FY26 (first discovered at Warwick) kills cancer cells by locating and attacking their weakest part. He said:
“Cancer drugs with new mechanisms of actions which can combat resistance and have fewer side-effects are urgently needed.”
More than half of all cancer chemotherapy treatments currently use platinum compounds; this is the first time that an Osmium-based compound has been seen to target the disease. FY26 has been shown to be more selective between normal cells and cancer cells than cisplatin, having a greater effect on cancer cells than on healthy ones. It is is 50 times more active than cisplatin.
Under the microscope
The researchers used the European Synchrotron Radiation Facility in Grenoble (France), a synchrotron source which emits extremely powerful X-ray beams.
Sadler that the nano-focussed X-ray beam allowed the team to locate the site of action of Organo-Osmium FY26 at “unprecedented resolution”.
Looking at sections of cancer cells under nano-focus, it was possible to observe in minute detail, detecting organelles like mitochondria, the “powerhouses” of cells that generate their energy.
In cancer cells, mutations in the DNA of mitochondria leave them susceptible to attack. FY26 was found to have positioned itself in the mitochondria, attacking and destroying the vital functions of cancer cells from within, at their weakest point.
“We could get a real picture of where the drug goes in a single cell using real-life pharmacological doses.”
Researchers were also able to see calcium and other metals moving around the cells. Calcium is known to affect the function of cells and it is thought that this naturally-produced metal helps FY26 to achieve an optimal position for attacking cancer.
"These kinds of experiments are normally performed using bigger doses than would be used in real life,” said Peter Cloetens, another member of the team.
“On the new nano-imaging ID16A beamline, by combining a very tight focus and high flux, we could get a real picture of where the drug goes in a single cell using real-life pharmacological doses."
From this, the team analysed the effects of Organo-Osmium FY26 in ovarian cancer cells, detecting emissions of X-ray fluorescent light to track the activity of the compound inside the cells.
This research can be applied and developed to other types of cancers, leading to new and more effective metal-based cancer targetting medications.