Test Better Measures Circulating Tumor Cells
Researchers from the A*STAR Institute of Micro-electronics Bioelectronics program in Singapore are developing a cost-effective and more rapid way to help physicians assess the effectiveness of treatments to cancer patients. The new device measures the level of circulating tumor cells (CTCs) in whole blood and it is expected to speed up the sample-to-answer process by more than 50%. There is currently only one clinically approved method for CTC analysis worldwide, which takes 3 to 7 days to process.
Circulating tumor cells are cells that have detached from a primary tumor and their circulation levels in the blood stream track the progression of cancer. The detection of CTCs is usually based on the presence of specific biomarker on their surfaces. To detect CTCs among a sea of red and white blood cells is like looking for a needle in a haystack. The current practice of measuring CTC uses a combination of complex magnetic forces and specific antibody-antigen interactions to isolate the CTCs. This is followed by laborious fluorescent tagging of the CTC before they can be detected and measured.
IME’s research endeavor may lower costs and speed up turnaround times for CTC analysis, allowing physicians to order the CTC test more frequently. This would facilitate a more informed and faster decision making process, which promises better management and potentially improved outcomes for patients, the researchers report.
The IME approach uses antigen-coated magnetic beads to capture the CTCs. The captured CTCs on the magnetic beads are then isolated before the CTCs are directly detected on the specially-treated microelectrode array (MEA). This way, the level of CTC is inferred from the impedance reading obtained.
Preliminary results showed that this device can detect one CTC directly from a pure cell standard – showing great promise as a sensitive test for cancer diagnosis.
This news was featured in the November/December issue of Drug Discovery & Development.