The ability to capture circulating tumor cells (CTCs) and diagnose the progression of cancer has become a key focus of research in recent years. However, a new innovative technology has been developed by scientists at UCLA that can improve the capture of circulating cancer cells, and hopefully offer better diagnosis and treatment-monitoring of the disease. The breakthrough uses Velcro-like nanoscale technology to efficiently identify and ‘grab’ CTCs in the blood [Wang et al. Angew Chem (2011) doi: 10.1002/anie.201005853].

Properly identifying the disease status of tumors usually depends on the invasive biopsy of tumor samples, and it can be difficult to find a satisfactory biopsy location. However, when CTCs are captured in blood samples a ‘liquid’ biopsy can be carried out, which makes early detection and diagnosis possible, and also improves both the monitoring of cancer progression and treatment responses.
The researchers were able to demonstrate the highly efficient enrichment of rare CTCs that had been captured from blood samples taken from patients suffering from prostate cancer. Circulating tumor cells have a crucial role to play in cancer metastasis, the most common cause of cancer-related deaths for patients that suffer from solid tumors. Cancer metastasis occurs when the tumor cells leave the main tumor site and move into other parts of the body.
The device makes tracking CTCs faster and cheaper than ever before, and also allows a greater number to be captured. Discussing the development of the second-generation technology, Dr. Hsian-Rong Tseng, senior author on the study, published in the journal Angewandte Chemie commented “The device features high flow of the blood samples, which travel at increased (lightning) speed.”
The paper reveals the technology significantly improves sensitivity in detecting rare CTCs from whole blood, and provides a viable alternative for monitoring cancer progression. Its capture rate is much higher, it is easier to operate than previous models, and it has an improved semi-automated interface that makes it more user-friendly than that of the previous versions.
The technology was developed from earlier work on ‘fly-paper’ technology involving a silicon chip covered in metamaterial nanopillars, The adhesive qualities come from the interaction between the nanopillars and microvilli, nanostructures on the CTCs, creating a similar effect to that of Velcro. An overlaid microfluidic channel creates a fluid flow path that improves mixing, resulting in CTCs having more contact with the nanopillar-covered floor and enhancing the efficiency of the device.
Such a device could offer a new way to explore cancer evolution by comparing CTCs with the primary tumor and the other metastases. It is hoped that CTC-analysis technology could lead to personalized cancer treatment and management in the future.

Laurie Donaldson