Single cancer cell detection improved
Researchers at the Karlsruhe Institute of Technology (KIT), Germany, and the Center for Nanotechnology, Munster, Ireland, have now developed a clinical method to help detect and isolate single cancer cells in blood samples before settling in tissue and forming a new tumour.
According to scientists, the main component of the new method is a microarray platform. By means of polymer pen lithography, a surface is provided with a microscopically small structure using a plastic die. The target cells adhere to these structures.
The blood sample to be investigated is injected into a flat microchannel that crosses the platform. As a maximum number of target cells is to contact the array, a fishbone-shaped structure at the top of the channel stirs up the passing liquid.
Giving details, KIT’s Michael Hirtz, said: “With our method, we reach a very high hit rate: more than 85% of the extracted cells really are cancer cells.
“In addition, we can sample suspicious cells undamaged and study them in more detail.”
The newly developed method can also be transferred to all applications, say the scientists, where rare cells in blood or other body liquids have to be isolated.
Explaining the principle, Hirtz added: “While the tumour cells dock to the prepared locations according to the key-lock principle, the remaining cells are simply washed away.”
In order to prevent the arrays, i.e. the locks from having to be exchanged for every application, the scientists provide all target cells with a general key: the biotin vitamin. In advance, this vitamin couples to the surface of the target cells via specific antibodies.
The number of extracted tumour cells allows conclusions to be drawn with respect to the success of therapy and the future course of the disease. Genetic analysis of cells allows therapies to be adapted to the type of cancer to be treated.
The scientists are now working on a prototype method that can be used at the hospital. For this, they are receiving funds from the European Research Council under the body’s Proof of Concept scheme.
The full study is published in Nature.
