A team from Bielefeld University in Germany has developed a molecule containing copper that binds specifically with DNA and prevents the spread of cancer. It demonstrates better results in killing cancer cells than cisplatin, a widely used anti-cancer drug that is frequently administered in chemotherapy.

Figure1: The new agent containing copper (above) ‘docks’ precisely with the DNA molecule (below) of a cancer cell and stops it from growing. As a result, the cancer cell dies. DOI: 10.1021/ic5028465

Doctors have been using cisplatin since 1970s to treat lung cancer and testicular cancer. However, cisplatin does not work to cure all type of cancers and it has many side effects (nausea, vomiting, and diarrhea). “Therefore we wanted to develop an alternative agent that would work differently, have fewer side effects, and treat other types of cancer as well” says Thorsten Glaser, Professor of Inorganic Chemistry at Bielefeld University. “In addition, we wanted an agent that would treat cancers that have become immune to cisplatin through its use in earlier treatments.”

While cisplatin binds with the nucleobases of the DNA, the new molecule developed by Thorsten’s team attacks the phosphate in the DNA. “We did this by integrating two metal ions of copper in our molecule that preferentially bind with phosphates” explained Professor Glaser. As soon as the copper ions bind with the phosphate, the DNA of the cancer cell changes, preventing it to reproduce and leading to cell apoptosis.

“Just as a key only works in one specific lock, our molecule only fits the phosphates and blocks them and because two phosphates bind simultaneously, the binding strength is greater. And that increases the efficacy” added Glaser. Professor Dario Anselmetti’s team (Biophysics and nanoscience) also from Bielefeld University used atomic force microscopy to produce the images confirming that the copper complex binds with the DNA.

Biochemists from Professor Gabriele Fischer von Mollard’s team applied the agent to cancer cell culture and studied its response. They found that the copper complex was more effective than cisplatin. With a concentration two times lower then when using cisplatin, the copper molecule could kill a maximum number of cancer cells.

The scientists at Bielefeld University have designed a procedure for manufacturing the new molecule. “How and whether the copper complex will actually be given to cancer patients is something that medical research will have to determine in the years to come” concluded Professor Glaser.