Molecular net can capture cancer cells in blood

A highly branched synthetic device, that functions as a net in the blood, could be beneficial in detecting the spread of cancer throughout the body. The branching makes sure it covers a lot of surface, which is populated with certain molecules able to recognize cells, and consequently bind to them. These antibodies recognize an adhesion molecule on the cell surface, which is often found to be upregulated in cancer cells. The device also consists of adhesion molecules found on the interior of blood vessels. In this way, the net mimics the vascular wall which the cancer cells use to bind and invade new organs. The scientists from the University of Illinois who created the device have shown that the binding strength is increased by a million-fold and the detection efficiency by sevenfold compared to conventional detection methods.

The increased efficiency of detecting cancer cells in the blood is most likely attributed to the spherical structure of the device surface, along with the branched polymers, which are dubbed dendrimers. Conventional detecting devices merely consist of a relatively flat surface, where binding only occurs through individual antibodies. Pegylation is used to hide the artificial device from the immune system. The newly developed branched structure renders multiple antibodies able to bind to the same cell, increasing the binding strength, and therefore the detection efficiency.

Capture and detection of circulating cancer cells is extremely important in tracking the cancer process. The spread of tumours from the initial organ to other organs, called metastasis, contributes significantly to its deadliness. However, only a few of the cancer cells manage to spread to other organs, which makes it harder to detect them in the blood. Increasing the binding strength of the detection device and its efficiency will therefore significantly aid cancer diagnosis.