Metal, which can be found in the asteroid blamed for the extinction of the dinosaur, can be used to target and destroy cancer cells, findings of a new research have suggested.
The metal, iridium, comes from the same family as platinum. It is brittle, yellow in color, hard, has a melting point of more than 2400 Celsius, and is the most corrosion-resistant metal in the world.
Brought To Earth By Chicxulub Asteroid That Killed Dinosaurs
The metal, which was discovered in 1803, is rare on Earth but it is abundant in meteoroids. Large amounts of this metal have been found in the Earth's crust from around 66 million years ago, which is about the same time the Chicxulub asteroid crashed on Earth. This leads to the theory that iridium, the second densest metal, was brought to Earth by the asteroid that caused the dinosaur's extinction.
"It's certainly now time to try to make good medical use of the iridium delivered to us by an asteroid 66 million years ago," said study researcher Peter Sadler, from the University of Warwick UK."
May Kill Cancer Cells Without Harming Healthy Tissues
In the new study, researchers showed that iridium, can kill cancer cells without causing harm to the healthy tissues and this can be done by filling the metal with a lethal version of oxygen.
Researchers created a compound made of iridium and organic metal that can be directly targeted towards cancer cells and transfer energy that can turn the oxygen inside these cells into a singlet oxygen, which can kill the cancerous cell sans harming any healthy tissue. The process involves photochemotherapy, which uses laser light, to target cancer.
In experiments, researchers attacked laboratory-grown tumor of lung cancer cells will red laser light that can penetrate deep into the skin. The process caused the organic-iridium to penetrate and infuse into each of the layers of the tumor to kill it.
Analysis of the proteins from the cancerous cells showed that the iridium compound destroyed the proteins for key molecules in cancer. Researchers likewise found that the treatment had no effect on non-cancerous tissue, which suggests it does not pose risk of harm to healthy cells.
"Selective activation of nontoxic photosensitizers in cancer cells by spatially-directed light is an attractive regimen for therapy because of the minimal damage to normal cells, especially if the sensitizer is preferentially taken up by cancer cells," the researchers wrote in their study.