In today’s Academic Minute, Dr. Nicholas Leadbeater of the University of Connecticut explains the biochemistry of highly targeted chemotherapy drugs.
Nicholas Leadbeater is an associate professor of organic and inorganic chemistry at the University of Connecticut, where he heads the New Synthetic Methods Group. Leadbeater and the NSMG research cleaner and more efficient methods for creating synthetic materials. Dr. Leadbeater holds a Ph.D. from Cambridge University, where he was a research fellow until 1999.
Dr. Nicholas Leadbeater, University of Connecticut – Chemotherapy Drugs
We all probably know a family member or friend who at some time has had a diagnosis of cancer. One of the first lines of treatment is often several rounds of chemotherapy. The objective of a chemotherapeutic drug is to kill the cancer cells selectively, leaving healthy cells alone. Cisplatin, a very simple compound containing the precious metal platinum, was serendipitously discovered in the 1960’s to have a high activity for killing cancer cells and is still used, together with variants, today.
Cisplatin works by binding selectively to cancerous cells. All cells, be they healthy or cancerous, contain DNA. The information in DNA is stored as a chemical code. The order, or sequence, of the chemical units in the DNA determines the information available for building and maintaining an organism, similar to the way in which letters of the alphabet appear in a certain order to form words and sentences. A key property of DNA is that it can replicate, or make copies of itself. This is critical when cells divide because each new cell needs to have an exact copy of the DNA present in the old cell. Cancerous cells often have a lot of places along the DNA strand where certain chemical units are next to one another, like words with double letters in them. Cisplatin binds strongly to these double letters and, by doing this, stops the cancer cells from reproducing. Since healthy cells do not have these double letters they are not affected as much.
Cisplatin has some side effects associated with its use. To try to overcome these, as well as make it even more selective for cancer cells, a range of improved platinum-containing drugs have been developed more recently and are currently either in use or in clinical trials.