Over 65 million years ago, an asteroid some 10 km (6 mi) wide crashed into the Earth and wiped out the dinosaurs. Strangely, the legacy of this huge space rock could include a treatment for cancer after scientists from the UK and China demonstrated that iridium – a rare metal delivered to Earth by the asteroid – can be enlisted to kill cancer without harming healthy cells.
Laser-based techniques are emerging as viable treatments for cancer, targeting tumors far more precisely than the shotgun blast of radiation and chemotherapy. In that vein, researchers from the University of Warwick in the UK and Sun Yat-Sen University in China have found that laser light can turn iridium into an effective cancer killer.
First, the team created a compound of iridium and organic materials, and then introduced it into a lung cancer tumor grown in the lab. When red laser light is shone onto it through the skin, the compound is activated, converting the oxygen in the tumor into singlet oxygen, a poisonous form of the element that effectively kills the cancer cells from the inside. With cancer becoming resistant to certain treatments, it’s crucial to find new methods such as this.