The aim is to develop molecular systems to counter cancer's ability to develop immunity to anticancer drugs and to help physicians focus their attack on cancer cells.
"We are building a new type of molecule that binds to DNA in new and different ways," says Brewer. "Tumors develop resistance to drug systems by changing or eliminating sites where drugs have been able to attach to the tumor. By changing the shape and the size of the molecule carrying the drug and the way the drug binds to DNA, we can continue to design systems that are effective against resistant tumor lines."
Early screening of the new molecules by the National Cancer Institute show that the new molecules do bind to the target DNA and have some anticancer activity, Brewer reports. The next steps are to increase the activity and introduce photoinitiation. The group will present news of their advances on these goals during the American Chemical Society meeting in San Francisco April 13-17.
Anticancer drugs such as chemotherapy often make people sick because, while the drugs are killing cancer cells, they are also damaging healthy cells.
Brewer, Shirley, and their students are designing drugs that would become active only when hit by light. Surgery would not be required because a low-level laser would deliver light in the near-infrared range through the skin to the tumor site. The light would activate the engineered molecules to bind to the DNA of the cancer cells and deliver killing drugs.
Virginia Tech graduate student Matthew Milkevitch delivered a paper on "Photochemical and DNA binding studies of platinum-ruthenium bimetallic compounds," on Sunday, April 13. Co-authors are Brewer, Shirley and undregraduate students Eric Brauns and Hannah Storrie.
The research is supported by the Jeffress Memorial Trust and the Virginia Tech Pilot Research Program.