CO2 to Kill Breast Cancer Cells
Researchers at the Johns Hopkins University have created a new device that can treat women with breast cancer in low-income countries by using carbon dioxide instead of argon, to power a cancer tissue-freezing probe.
The currently used method relies on discharging argon from the tip of a needle very quickly to reduce the temperature to a level that allows the formation of ice balls around the tumor tissue.
Then, helium is emptied from the head of the needle, driving the temperature up from 20 to 40 degrees Celsius, to swiftly melt and dissolve the ice balls, and lead to the collapse of tumor tissue.
A report published on the university's website said: "these techniques are too expensive, with a single treatment costing upwards of $10,000, and are dependent on argon gas, which typically isn't available in lower-income countries. This led the researchers to consider using the carbon dioxide, which is already widely available in most rural areas thanks to the popularity of carbonated drinks."
In their study published in the latest issue of the Plos One journal, the researchers designed a freezing system that allows the solidification of carbon dioxide inside the tumor tissues to form the so-called "ice balls" widely used in preserving frozen foods.
The researchers tested their tool in three experiments. In the first, they used the tool on jars of ultrasound gel that successfully formed ice balls.
For the second experiment, the team treated 9 rats with 10 mammary tumors. The tool successfully killed 85% or more tissue for all tumors. Finally, the team tested the tool's ability to destroy tissues in the normal liver of a pig, which has a temperature similar to a human breast.
Commenting on the findings, the study lead author Bailey Surtees said: "Innovation in cancer care doesn't always mean you have to create an entirely new treatment, sometimes it means radically innovating on proven therapies such that they're redesigned to be accessible to the majority of the world's population."