Metal in Asteroids Can Kill Cancer Cells

     A collaboration between Warwick University and Sun Yat-Sen University in China recently found through their research that a metal in asteroids can be used to kill cancer cells without harming healthy ones. The article from Science Daily, talks about Professors Sadler and O'Connor (Warwick University) and Professor Hui Chao's group at Sun Yat-Sen and their findings about iridium metal. The iridium metal can kill cancer cells by filling them with a deadly version of oxygen, which does not harm the healthy cells around it. An iridium and an organic material compound transfers energy to the cancerous cells to turn O2 into a single oxygen atom, which is poisonous. 
     The researcher's experimentation involved shining a laser through the skin and onto the cancerous region, where the light then activates the iridium metal and begins creating oxygen. The process was tested on a model of a lung tumor and was proved effective; not only is the process safe, but they found that when applying the technique to healthy cells, no effect was observed. Photochemotherapy, using a laser light to target cancer, describes the researchers procedure, and proves to be effective and non-invasive. 
     Mass spectrometry was used to examine which proteins within the cancer cells attacked the actual iridium organic compound. Cooksen Chui, a postgraduate researcher from Warwick's Department of Chemistry replied to this project as "a leap forward in understanding how these new iridium-based anti-cancer compounds are attacking cancer cells, introducing different mechanisms of action, to get around the resistance issue and tackle cancer from a different angle." Because the researchers are identifying the proteins involved in the cancerous cells, "novel drugs with new mechanisms of action" are on the rise. 

     It is not a shock that the second densest metal, iridium, is being used to treat cancer. Platinum has been known to be used in at least 50% of cancer chemotherapies, but does cause serious side effects post treatment. The use of iridium through photochemotherapy gives hope for new drugs and safer treatments for those with cancer. 

Iridium was first discovered in 1803, and is similar to the metal, Platinum. It is almost nonreactive and resistant to corrosion with a melting point over 2400 °C. Iridium is interesting because it is rarely found on earth, but is very abundant in meteoroids. Large amounts of iridium from 66 million years ago has been found in the Earth's crust, and many believe in a theory that states iridium came to earth from the asteroid that caused the extinction of dinosaurs. 

References 
University of Warwick. "Cancer cells destroyed with dense metal found in asteroids." ScienceDaily. ScienceDaily, 2 November 2017. <www.sciencedaily.com/releases/2017/11/171102105839.htm>.